Condition of having pores or open spaces. This often refers to bones, bone implants, or bone cements, but can refer to the porous state of any solid substance.
A circular structural unit of bone tissue. It consists of a central hole, the Haversian canal through which blood vessels run, surrounded by concentric rings, called lamellae.
The testing of materials and devices, especially those used for PROSTHESES AND IMPLANTS; SUTURES; TISSUE ADHESIVES; etc., for hardness, strength, durability, safety, efficacy, and biocompatibility.
The maximum compression a material can withstand without failure. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed, p427)
Cell growth support structures composed of BIOCOMPATIBLE MATERIALS. They are specially designed solid support matrices for cell attachment in TISSUE ENGINEERING and GUIDED TISSUE REGENERATION uses.
Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.
Polymers of organic acids and alcohols, with ester linkages--usually polyethylene terephthalate; can be cured into hard plastic, films or tapes, or fibers which can be woven into fabrics, meshes or velours.
Generating tissue in vitro for clinical applications, such as replacing wounded tissues or impaired organs. The use of TISSUE SCAFFOLDING enables the generation of complex multi-layered tissues and tissue structures.
Synthetic or natural materials, other than DRUGS, that are used to replace or repair any body TISSUES or bodily function.
Material from which the casting mold is made in the fabrication of gold or cobalt-chromium castings. (Boucher's Clinical Dental Terminology, 4th ed, p168)
Production of a radiographic image of a small or very thin object on fine-grained photographic film under conditions which permit subsequent microscopic examination or enlargement of the radiograph at linear magnifications of up to several hundred and with a resolution approaching the resolving power of the photographic emulsion (about 1000 lines per millimeter).
Synthetic or natural materials for the replacement of bones or bone tissue. They include hard tissue replacement polymers, natural coral, hydroxyapatite, beta-tricalcium phosphate, and various other biomaterials. The bone substitutes as inert materials can be incorporated into surrounding tissue or gradually replaced by original tissue.
Substances made up of an aggregation of small particles, as that obtained by grinding or trituration of a solid drug. In pharmacy it is a form in which substances are administered. (From Dorland, 28th ed)
Characteristics or attributes of the outer boundaries of objects, including molecules.
X-RAY COMPUTERIZED TOMOGRAPHY with resolution in the micrometer range.
A biocompatible polymer used as a surgical suture material.
Artificial substitutes for body parts and materials inserted into organisms during experimental studies.
The species Balaena mysticetus, in the family Balaenidae, found in the colder waters of the Northern Hemisphere. The common name is derived from the extreme arching of the lower jaw.
Calcium salts of phosphoric acid. These compounds are frequently used as calcium supplements.
The longest and largest bone of the skeleton, it is situated between the hip and the knee.
The mineral component of bones and teeth; it has been used therapeutically as a prosthetic aid and in the prevention and treatment of osteoporosis.
A specialized CONNECTIVE TISSUE that is the main constituent of the SKELETON. The principle cellular component of bone is comprised of OSTEOBLASTS; OSTEOCYTES; and OSTEOCLASTS, while FIBRILLAR COLLAGENS and hydroxyapatite crystals form the BONE MATRIX.
Solid dosage forms, of varying weight, size, and shape, which may be molded or compressed, and which contain a medicinal substance in pure or diluted form. (Dorland, 28th ed)
Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).
The mechanical property of material that determines its resistance to force. HARDNESS TESTS measure this property.
Adhesives used to fix prosthetic devices to bones and to cement bone to bone in difficult fractures. Synthetic resins are commonly used as cements. A mixture of monocalcium phosphate, monohydrate, alpha-tricalcium phosphate, and calcium carbonate with a sodium phosphate solution is also a useful bone paste.
Products made by baking or firing nonmetallic minerals (clay and similar materials). In making dental restorations or parts of restorations the material is fused porcelain. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed & Boucher's Clinical Dental Terminology, 4th ed)
A group of thermoplastic or thermosetting polymers containing polyisocyanate. They are used as ELASTOMERS, as coatings, as fibers and as foams.
Relating to the size of solids.
Transparent, tasteless crystals found in nature as agate, amethyst, chalcedony, cristobalite, flint, sand, QUARTZ, and tridymite. The compound is insoluble in water or acids except hydrofluoric acid.
A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.
The continuous turnover of BONE MATRIX and mineral that involves first an increase in BONE RESORPTION (osteoclastic activity) and later, reactive BONE FORMATION (osteoblastic activity). The process of bone remodeling takes place in the adult skeleton at discrete foci. The process ensures the mechanical integrity of the skeleton throughout life and plays an important role in calcium HOMEOSTASIS. An imbalance in the regulation of bone remodeling's two contrasting events, bone resorption and bone formation, results in many of the metabolic bone diseases, such as OSTEOPOROSIS.
A plant genus of the family OLEACEAE. Members contain secoiridoid glucosides.
Nanometer-scale composite structures composed of organic molecules intimately incorporated with inorganic molecules. (Glossary of Biotechnology and Nanobiotechology Terms, 4th ed)
The maximum stress a material subjected to a stretching load can withstand without tearing. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed, p2001)
A group of phosphate minerals that includes ten mineral species and has the general formula X5(YO4)3Z, where X is usually calcium or lead, Y is phosphorus or arsenic, and Z is chlorine, fluorine, or OH-. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Submicron-sized fibers with diameters typically between 50 and 500 nanometers. The very small dimension of these fibers can generate a high surface area to volume ratio, which makes them potential candidates for various biomedical and other applications.
Renewal or repair of lost bone tissue. It excludes BONY CALLUS formed after BONE FRACTURES but not yet replaced by hard bone.
Physical reactions involved in the formation of or changes in the structure of atoms and molecules and their interactions.
The shaft of long bones.
Property of membranes and other structures to permit passage of light, heat, gases, liquids, metabolites, and mineral ions.
The family of carnivorous or omnivorous bears, having massive bodies, coarse heavy fur, relatively short limbs, and almost rudimentary tails.
The preparation, mixing, and assembling of a drug. (From Remington, The Science and Practice of Pharmacy, 19th ed, p1814)
A polymer prepared from polyvinyl acetates by replacement of the acetate groups with hydroxyl groups. It is used as a pharmaceutic aid and ophthalmic lubricant as well as in the manufacture of surface coatings artificial sponges, cosmetics, and other products.
Deacetylated CHITIN, a linear polysaccharide of deacetylated beta-1,4-D-glucosamine. It is used in HYDROGEL and to treat WOUNDS.
The properties, processes, and behavior of biological systems under the action of mechanical forces.
The evaluation of incidents involving the loss of function of a device. These evaluations are used for a variety of purposes such as to determine the failure rates, the causes of failures, costs of failures, and the reliability and maintainability of devices.
The outer shorter of the two bones of the FOREARM, lying parallel to the ULNA and partially revolving around it.
Materials which have structured components with at least one dimension in the range of 1 to 100 nanometers. These include NANOCOMPOSITES; NANOPARTICLES; NANOTUBES; and NANOWIRES.
Process by which unwanted microbial, plant or animal materials or organisms accumulate on man-made surfaces.
A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A plant genus of the family FABACEAE.
The second longest bone of the skeleton. It is located on the medial side of the lower leg, articulating with the FIBULA laterally, the TALUS distally, and the FEMUR proximally.
Water swollen, rigid, 3-dimensional network of cross-linked, hydrophilic macromolecules, 20-95% water. They are used in paints, printing inks, foodstuffs, pharmaceuticals, and cosmetics. (Grant & Hackh's Chemical Dictionary, 5th ed)
Numerical expression indicating the measure of stiffness in a material. It is defined by the ratio of stress in a unit area of substance to the resulting deformation (strain). This allows the behavior of a material under load (such as bone) to be calculated.
A dark-gray, metallic element of widespread distribution but occurring in small amounts; atomic number, 22; atomic weight, 47.90; symbol, Ti; specific gravity, 4.5; used for fixation of fractures. (Dorland, 28th ed)
Chemistry dealing with the composition and preparation of agents having PHARMACOLOGIC ACTIONS or diagnostic use.
Quartz (SiO2). A glassy or crystalline form of silicon dioxide. Many colored varieties are semiprecious stones. (From Grant & Hackh's Chemical Dictionary, 5th ed)
The use of computers for designing and/or manufacturing of anything, including drugs, surgical procedures, orthotics, and prosthetics.
The amount of mineral per square centimeter of BONE. This is the definition used in clinical practice. Actual bone density would be expressed in grams per milliliter. It is most frequently measured by X-RAY ABSORPTIOMETRY or TOMOGRAPHY, X RAY COMPUTED. Bone density is an important predictor for OSTEOPOROSIS.
The joining of objects by means of a cement (e.g., in fracture fixation, such as in hip arthroplasty for joining of the acetabular component to the femoral component). In dentistry, it is used for the process of attaching parts of a tooth or restorative material to a natural tooth or for the attaching of orthodontic bands to teeth by means of an adhesive.
A cellulose derivative which is a beta-(1,4)-D-glucopyranose polymer. It is used as a bulk laxative and as an emulsifier and thickener in cosmetics and pharmaceuticals and as a stabilizer for reagents.
Mature osteoblasts that have become embedded in the BONE MATRIX. They occupy a small cavity, called lacuna, in the matrix and are connected to adjacent osteocytes via protoplasmic projections called canaliculi.
A generic grouping for dihydric alcohols with the hydroxy groups (-OH) located on different carbon atoms. They are viscous liquids with high boiling points for their molecular weights.
Salts and esters of the 10-carbon monocarboxylic acid-decanoic acid.
The growth action of bone tissue as it assimilates surgically implanted devices or prostheses to be used as either replacement parts (e.g., hip) or as anchors (e.g., endosseous dental implants).
Magnesium oxide (MgO). An inorganic compound that occurs in nature as the mineral periclase. In aqueous media combines quickly with water to form magnesium hydroxide. It is used as an antacid and mild laxative and has many nonmedicinal uses.
A process of separating particulate matter from a fluid, such as air or a liquid, by passing the fluid carrier through a medium that will not pass the particulates. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The buckthorn plant family, of the order Rhamnales, includes some species with edible fruits and some that are medicinal.
A normal intermediate in the fermentation (oxidation, metabolism) of sugar. The concentrated form is used internally to prevent gastrointestinal fermentation. (From Stedman, 26th ed)
Small uniformly-sized spherical particles, of micrometer dimensions, frequently labeled with radioisotopes or various reagents acting as tags or markers.
Method of tissue preparation in which the tissue specimen is frozen and then dehydrated at low temperature in a high vacuum. This method is also used for dehydrating pharmaceutical and food products.
Polyester polymers formed from terephthalic acid or its esters and ethylene glycol. They can be formed into tapes, films or pulled into fibers that are pressed into meshes or woven into fabrics.
The process of bone formation. Histogenesis of bone including ossification.
A plant family of the order Violales, subclass Dilleniidae, class Magnoliopsida. Bixa contains bixin. Cochlospermum contains arjunolic acid and gum kondagogu (POLYSACCHARIDES).
The quality or state of being wettable or the degree to which something can be wet. This is also the ability of any solid surface to be wetted when in contact with a liquid whose surface tension is reduced so that the liquid spreads over the surface of the solid.
A polyester used for absorbable sutures & surgical mesh, especially in ophthalmic surgery. 2-Hydroxy-propanoic acid polymer with polymerized hydroxyacetic acid, which forms 3,6-dimethyl-1,4-dioxane-dione polymer with 1,4-dioxane-2,5-dione copolymer of molecular weight about 80,000 daltons.
Usually inert substances added to a prescription in order to provide suitable consistency to the dosage form. These include binders, matrix, base or diluent in pills, tablets, creams, salves, etc.
The process of producing a form or impression made of metal or plaster using a mold.
A network of cross-linked hydrophilic macromolecules used in biomedical applications.
Tantalum. A rare metallic element, atomic number 73, atomic weight 180.948, symbol Ta. It is a noncorrosive and malleable metal that has been used for plates or disks to replace cranial defects, for wire sutures, and for making prosthetic devices. (Dorland, 28th ed)
A space in which the pressure is far below atmospheric pressure so that the remaining gases do not affect processes being carried on in the space.
Resistance and recovery from distortion of shape.
The application of scientific knowledge or technology to pharmacy and the pharmaceutical industry. It includes methods, techniques, and instrumentation in the manufacture, preparation, compounding, dispensing, packaging, and storing of drugs and other preparations used in diagnostic and determinative procedures, and in the treatment of patients.
The dormant state in which some warm-blooded animal species pass the winter. It is characterized by narcosis and by sharp reduction in body temperature and metabolic activity and by a depression of vital signs.
Computer-assisted study of methods for obtaining useful quantitative solutions to problems that have been expressed mathematically.
Polymerized methyl methacrylate monomers which are used as sheets, moulding, extrusion powders, surface coating resins, emulsion polymers, fibers, inks, and films (From International Labor Organization, 1983). This material is also used in tooth implants, bone cements, and hard corneal contact lenses.
Implants constructed of materials designed to be absorbed by the body without producing an immune response. They are usually composed of plastics and are frequently used in orthopedics and orthodontics.
The largest of three bones that make up each half of the pelvic girdle.
Process by which organic tissue becomes hardened by the physiologic deposit of calcium salts.
A trace element that constitutes about 27.6% of the earth's crust in the form of SILICON DIOXIDE. It does not occur free in nature. Silicon has the atomic symbol Si, atomic number 14, and atomic weight [28.084; 28.086].
Hard, amorphous, brittle, inorganic, usually transparent, polymerous silicate of basic oxides, usually potassium or sodium. It is used in the form of hard sheets, vessels, tubing, fibers, ceramics, beads, etc.
Procedures for enhancing and directing tissue repair and renewal processes, such as BONE REGENERATION; NERVE REGENERATION; etc. They involve surgically implanting growth conducive tracks or conduits (TISSUE SCAFFOLDING) at the damaged site to stimulate and control the location of cell repopulation. The tracks or conduits are made from synthetic and/or natural materials and may include support cells and induction factors for CELL GROWTH PROCESSES; or CELL MIGRATION.
Dosage forms of a drug that act over a period of time by controlled-release processes or technology.
A polyvinyl polymer of variable molecular weight; used as suspending and dispersing agent and vehicle for pharmaceuticals; also used as blood volume expander.
A product formed from skin, white connective tissue, or bone COLLAGEN. It is used as a protein food adjuvant, plasma substitute, hemostatic, suspending agent in pharmaceutical preparations, and in the manufacturing of capsules and suppositories.
Tablets coated with material that delays release of the medication until after they leave the stomach. (Dorland, 28th ed)

Coating titanium implants with bioglass and with hydroxyapatite. A comparative study in sheep. (1/1668)

This study compares the osteointegration of titanium implants coated with bioglass (Biovetro GSB formula) and with hydroxyapatite (HAP). Twenty-four bioglass-coated and 24 HAP-coated cylinders were implanted in the femoral diaphyses of sheep, and examined after 2, 4, 6, 8, 12, and 16 weeks. The HAP coating gave a stronger and earlier fixation to the bone than did bioglass. Bioglass formed a tissue interface which showed a macrophage reaction with little new bone formation activity. In contrast, HPA, showed intense new bone formation, with highly mineralised osseous trabeculae in the neighbourhood of the interface.  (+info)

Enthacrynic and acid effects on inner wall pores in living monkeys. (2/1668)

PURPOSE: The influence of the inner wall of Schlemm's canal on aqueous outflow facility remains poorly understood. We examined the relationship between inner wall pore characteristics and outflow facility in living primate eyes in which facility had been pharmacologically increased by ethacrynic acid (ECA) infusion and in contralateral control eyes. METHODS: Outflow facility (two-level constant pressure perfusion) was measured in eight pairs of living monkey eyes before and after administration of a bolus dose of either 0.125 mM ECA or vehicle. After exsanguination, eyes were fixed in situ under constant-pressure conditions (mean fixation pressure approximately 19 mm Hg). The density and diameter of inner wall pores and the number and area of platelet aggregates on the inner wall of Schlemm's canal were measured by scanning electron microscopy. RESULTS: In ECA-treated eyes, outflow facility increased 63% (P < 0.0001), intracellular pore density decreased 46% (P = 0.0094), intracellular pore size increased 27% (P = 0.049), platelet aggregate density increased 158% (P < 0.0001), and area covered by platelets increased 210% (P = 0.012) relative to contralateral controls. Although the average density and size of intercellular pores were essentially unaffected by ECA, an increased density of large (> or = 1.90 microm) intercellular pores was seen in ECA-treated eyes. The density of intracellular pores increased with the duration of fixative perfusion. Other than a weak negative correlation between outflow facility and intracellular pore density in ECA-treated eyes (P = 0.052), facility was not correlated with inner wall pore features. CONCLUSIONS: Our data are most consistent with a scenario in which ECA promotes formation of large intercellular pores in the inner wall of Schlemm's canal, which are then masked by platelet aggregates. Masking of intercellular pores, combined with fixation-induced alteration of inner wall pore density, greatly complicates attempts to relate facility to inner wall structure and suggests that in vivo pore density is smaller than in fixed tissue. Additionally, facility-influencing effects of ECA on the juxtacanalicular tissue cannot be excluded.  (+info)

Effects of ethacrynic acid on Schlemm's canal inner wall and outflow facility in human eyes. (3/1668)

PURPOSE: The role of the inner wall of Schlemm's canal in determining aqueous outflow facility is poorly understood. To quantify the relationship between inner wall pore characteristics and aqueous outflow facility in human eyes, both control eyes and eyes in which facility had been pharmacologically increased by ethacrynic acid (ECA) infusion were studied. METHODS: Outflow facility was measured in enucleated human eyes before and after delivery of 0.25 mM ECA (one eye of each of 6 pairs) or 2.5 mM ECA (one eye of each of 13 pairs). ECA, and vehicle in contralateral eyes, was delivered into Schlemm's canal by retroperfusion, thereby largely avoiding drug exposure to the trabecular meshwork. After facility measurement, eyes were fixed under conditions of either constant pressure (physiological intraocular pressure, 13 pairs) or "equal flow" (6 pairs) and were microdissected to expose the inner wall of Schlemm's canal. The density and diameter of intercellular and intracellular inner wall pores were measured using scanning electron microscopy. RESULTS: Retroperfusion with 2.5 mM ECA increased facility by 73% (P < 0.001), whereas 0.25 mM ECA increased facility by 19% (not statistically significant). The density of intercellular pores in the inner wall of Schlemm's canal was increased by 520% in 2.5 mM ECA-retroperfused eyes (P < 0.00004), whereas intracellular pore density remained approximately constant. Large pores (size > or = 1.1 microm) were particularly enhanced in ECA retroperfused eyes. The net change in facility due to ECA was not correlated with changes in pore density or other inner wall pore statistics. CONCLUSIONS: Our data are most consistent with a model in which pores in the inner wall of Schlemm's canal indirectly influence facility. However, measured changes in facility due to changes in inner wall properties did not agree with quantitative predictions of the pore funneling theory, suggesting that changes in facility may instead be due to gel leakage from the extracellular spaces of the juxtacanalicular tissue. More definitive experiments are required to confirm this hypothesis.  (+info)

Diffusion of macromolecules in agarose gels: comparison of linear and globular configurations. (4/1668)

The diffusion coefficients (D) of different types of macromolecules (proteins, dextrans, polymer beads, and DNA) were measured by fluorescence recovery after photobleaching (FRAP) both in solution and in 2% agarose gels to compare transport properties of these macromolecules. Diffusion measurements were conducted with concentrations low enough to avoid macromolecular interactions. For gel measurements, diffusion data were fitted according to different theories: polymer chains and spherical macromolecules were analyzed separately. As chain length increases, diffusion coefficients of DNA show a clear shift from a Rouse-like behavior (DG congruent with N0-0.5) to a reptational behavior (DG congruent with N0-2.0). The pore size, a, of a 2% agarose gel cast in a 0.1 M PBS solution was estimated. Diffusion coefficients of the proteins and the polymer beads were analyzed with the Ogston model and the effective medium model permitting the estimation of an agarose gel fiber radius and hydraulic permeability of the gels. Not only did flexible macromolecules exhibit greater mobility in the gel than did comparable-size rigid spherical particles, they also proved to be a more useful probe of available space between fibers.  (+info)

Molecular mechanism for pore-formation in lipid membranes by the hemolytic lectin CEL-III from marine invertebrate Cucumaria echinata. (5/1668)

The pore-forming activity of CEL-III, a Gal/GalNAc specific lectin from the Holothuroidea Cucumaria echinata, was examined using artificial lipid membranes as a model system of erythrocyte membrane. The carboxyfluorescein (CF)-leakage studies clearly indicated that CEL-III induced the formation of pores in the dipalmitoyl phosphatidyl choline (DPPC)-lactosyl ceramide (LacCer) liposomes effectively but not in the DPPC-glucosyl ceramide (GlcCer) liposomes or DPPC liposomes. Such a leakage of CF was strongly inhibited by lactose, a potent inhibitor of CEL-III, suggesting that the leakage is mediated through the specific binding of CEL-III to the carbohydrate chains on the surface of the liposomes. The leakage of CF from the DPPC-lactosyl ceramide liposomes was pH-dependent, and it increased with increasing pH. The immunoblotting analysis and circular dichroism data indicated that upon interaction with liposomes, CEL-III associated to form an oligomer concomitantly with a marked conformational change. Furthermore, channel measurements showed that CEL-III has an ability to form small ion channels in the planar lipid bilayers consisting of diphytanoylphosphatidylcholine and human globoside (Gb4Cer)/LacCer.  (+info)

Heat stress and protective clothing: an emerging approach from the United States. (6/1668)

There is little doubt that heat stress affects many workers adversely and that protective clothing generally adds to the burden. The ACGIH threshold limit value for heat stress is the guiding document for evaluation of heat stress in the United States. Adjustment factors have been used to reflect the change in heat stress imposed by different clothing ensembles. While the first proposed factors started with limited experimental data and professional judgment, heat balance methods in the laboratory have yielded better estimates of adjustment factors and for a wider selection of ensembles. These same experiments have provided the starting point to accounting for nonporous clothing in heat balance evaluation schemes such as required sweat rate. Proposed changes to the ACGIH TLV have been mentioned and a framework for thinking about controls presented.  (+info)

Field testing of a personal size-selective bioaerosol sampler. (7/1668)

Existing samplers for the collection of bioaerosols have been designed with the aim of maintaining biological stability of the collected material, and in general do not select particles in accordance with international conventions for aerosol sampling. Many have uncharacterised sampling efficiencies and few are designed as personal samplers. If standard personal dust samplers are used for bioaerosols the viability of collected microorganisms may be compromised by dehydration. The objective of this study was to evaluate a novel personal bioaerosol sampler designed to collect the inhalable dust fraction and further subdivide the sample into thoracic and respirable fractions. The new sampler was tested to see whether it enhanced the survival of the collected microorganisms, and was assessed for ease of use in the field and in subsequent laboratory analyses. A number of occupation-related field sites were selected where large concentrations of bioaerosols were to be expected. The prototype sampler was found to be simple to use. Analysis could be carried out with similar efficiency either with all three fractions together for a total count, or separately for size selective data. The sampler performed at least as well as the standard IOM filter method but with the added advantage of size fractionation. The field trials showed that for sampling periods lasting several hours, microorganism survival within the sampler was adequate for culture and identification of the organisms present. This new sampler is now commercially available. In addition to bioaerosol sampling, the principle of size selective sampling using porous foams can be applied to other occupational hygiene problems, and also to indoor air monitoring of PM10 and PM2.5 concentrations.  (+info)

Molecular dynamics of synthetic leucine-serine ion channels in a phospholipid membrane. (8/1668)

Molecular dynamics calculations were carried out on models of two synthetic leucine-serine ion channels: a tetrameric bundle with sequence (LSLLLSL)(3)NH(2) and a hexameric bundle with sequence (LSSLLSL)(3)NH(2). Each protein bundle is inserted in a palmitoyloleoylphosphatidylcholine bilayer membrane and solvated by simple point charge water molecules inside the pore and at both mouths. Both systems appear to be stable in the absence of an electric field during the 4 ns of molecular dynamics simulation. The water motion in the narrow pore of the four-helix bundle is highly restricted and may provide suitable conditions for proton transfer via a water wire mechanism. In the wider hexameric pore, the water diffuses much more slowly than in bulk but is still mobile. This, along with the dimensions of the pore, supports the observation that this peptide is selective for monovalent cations. Reasonable agreement of predicted conductances with experimentally determined values lends support to the validity of the simulations.  (+info)

Last week, I put up a post about good moisturizers for low porosity hair. This time, I want to talk about high porosity hair (you didnt think I would leave this out did you?). If you dont know how to test the difference, read this post. Unlike low porosity hair, high porosity hair absorbs moisture really well. However, it also loses moisture easily. Because the hair cuticles are often open, its hard for high porous hair to retain moisture. High porous hair can be attributed to heat damage, poor hair maintenance, harsh hair dyes or just good ole genes. Its usually thin and can break easily if not properly maintained. High porosity hair needs heavier products and sealants to aid in retaining moisture. Products that contain butters and thicker oils like shea butter, mango butter, babassu oil, olive oil and avocado oil can help to retain moisture high porosity hair. Also, protein-rich products aid in strengthen the hair. Proteins temporarily fill the porous gaps leaving the hair stronger and ...
A catalyst and a method of preparation of said catalyst is described herein. The catalyst includes one or more metals from Columns 6-10 of the Periodic Table and/or one or more compounds of one or more metals from Columns 6-10 of the Periodic Table, a pore size distribution with a median pore diameter ranging from 105 Å to 150 Å, with 60% of the total number of pores in the pore size distribution having a pore diameter within 60 Å of the median pore diameter, with at least 50% of its pore volume in pores having a pore diameter of at most 600 Å, and between 5% and 25% of its pore volume in pores having a pore diameter between 1000 Å and 5000 Å. Methods of producing said catalyst are described herein. Crude products and products made from said crude products are described herein.
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Dry, rough and unmanageable curls can turn the best of days into a bad hair day. Protect your hair with SheaMoistures High Porosity Moisture-Seal Masque formulated using ultra-hydrating Mongongo and Hemp Seed Oils to transform porous, over processed , damaged hair into soft, smooth, frizz-free curls and coils.High Porosity hair shaft cuticles are open causing the hair to lose moisture almost as soon as it is absorbed. Low moisture retention causes split ends, makes your curls rough, dry and prone to breakage. SheaMoistures High Porosity Moisture-Seal Masque is enriched with Mongongo and Hemp Seed Oils which seals in moisture by closing hair cuticles, forming a protective layer over your curls, leaving you hair bouncy, nourished and oh-so-amazing!SheaMoistures High Porosity Moisture-Seal Masque is fortified with natural ingredients like Baobab Proteins, Apple Cider Vinegar and certified organic Shea Butter which smooths down the cuticles of the hair shaft leaving you hair moisturized, smooth and
Swelling of Cellulosic Porous Materials - Mathematical Description and Verification. Anton Geffert,a,* Ondrej Vacek,b Andrej Jankech,b Jarmila Geffertová,a and Miloslav Milichovský c. The swelling of natural porous materials, including bleached pulp, as represented by mathematical descriptions, is influenced by a variety of different operating factors. The formerly used Generalised Hygroscopicity Model leads to either a disproportion between a model and a limit value of the sorption capacity or to noticeable deviation in the early swelling phase. Alternatively, the so-called Simple Bounded Growth model solely depends on the maximum sorption capacity, ignoring the physical properties that affect the fibre swelling rate. This research shows that the combination of the two models best describes the swelling process of bleached pulp - a rapid swelling phase and a slower swelling phase. The combined model was found to be useful in characterizing the well-known hornification process.. Contact ...
TY - GEN. T1 - The role of surface chemistry and porosity on the adsorption of inflammatory mediators. AU - Murphy, M. C.. AU - Phillips, G. J.. AU - Lloyd, A. W.. AU - Davies, J. G.. AU - Mikhalovsky, S. V.. PY - 2004/12/1. Y1 - 2004/12/1. N2 - The role of surface chemistry and porosity on the adsorption of inflammatory mediators was analyzed. It was found that the removal of lipopolysaccharide (LPS) and proinflammatory cytokines from the circulation was capable of providing a therapy to counteract sepsis. It was observed that all MAST carbons exhibited poor adsorption capability for LPS. The results show that porosity is helpful in the adsorption of LPS.. AB - The role of surface chemistry and porosity on the adsorption of inflammatory mediators was analyzed. It was found that the removal of lipopolysaccharide (LPS) and proinflammatory cytokines from the circulation was capable of providing a therapy to counteract sepsis. It was observed that all MAST carbons exhibited poor adsorption ...
Hair care tips for high porosity hair are very important. If your hair is low porosity, then its not going to have any problems with hair growth. However, if your hair is high porosity, then you need to take special measures to make sure that your hair grows properly. For example, if youre having trouble growing out your locks because theyre too coarse or thick and heavy, then there might be some things that can help you get rid of these issues.. The main thing is that you need to know what to do so that your hair doesnt become brittle or break off. Also, if you want to keep your hair healthy and strong, then you need to take proper care of it.. You dont want it breaking easily when doing physical activities like running around or working out.. There are various ways to deal with the problem of high porosity hair. Some of them include:. 1) Use a product containing proteins such as casein or soy protein.. These types of products will help your hair retain moisture better and prevent damage ...
Porous materials have application in adsorption based processes due to their high internal surface area and tailorable pore size. They find uses in fields such as catalysis, separation, biotechnology, and microelectronics. Fluids confined in such materials exhibit interesting behavior in regards to the condensation and evaporation mechanisms. Understanding study the behavior of fluids confined in these porous materials is necessary for the efficient design of these materials. The adsorption/desorption isotherm provides valuable information about the effect of network features like pore connectivity and pore size distribution on fluid behavior during pore condensation and evaporation. Such insight can be useful in the characterization of these porous materials. Three dimensionally ordered mesoporous (3DOm) carbon is a porous material that has recently emerged and is of interest. These porous structures are obtained from templating colloidal crystals formed from lysine-silica nanoparticles. The resulting
TY - JOUR. T1 - Molecular simulation study on adsorption of methanol/water mixtures in mesoporous silicas modified pore surface silylation. AU - Aoyama, Naoki. AU - Yoshihara, Tsukasa. AU - Furukawa, Shin ichi. AU - Nitta, Tomoshige. AU - Takahashi, Hideaki. AU - Nakano, Masayoshi. N1 - Funding Information: The research was partly supported by a Grant-in-Aid for Young Scientists (B) (No. 17760600) from the Ministry of Education, Science, Sports and Culture, Japan.. PY - 2007/8/25. Y1 - 2007/8/25. N2 - Two types of molecular simulation techniques have been utilized to investigate adsorption of methanol/water mixtures in a mesoporous silica with a hydrophobic pore surface: the NVT-ensemble Molecular Dynamics method with the melt-quench algorithm for modeling a fully-silylated mesoporous silica and the μVT-ensemble Orientaional-Biased Monte Carlo method for calculating adsorption isotherms. Adsorption isotherms of methanol and water at 333 K are calculated for an equi-relative-pressure mixture ...
Treat rough, unmanageable, damaged or dry hair with High Porosity Moisture-Seal Shampoo from SheaMoisture. This sulfate-free highly moisturizing shampoo is specially formulated for deep thorough cleansing of scalp and rough, damaged curls and coils prone to frizz, dryness and breakage.Dry hair, dehydrated and low moisture hair, feels rough, is frizzy or dull with split-ends and is shedding. This ultra-moisture rich shampoo wont strip, tangle or dry out your hair. SheaMoistures High Porosity Moisture-Seal Shampoo is enriched with Mongongo and Hemp Seed Oils, which repairs damage and seals moisture into your hair cuticles making your curls or coils feel smooth and nourished.Natural ingredients like Baobab Proteins and Apple Cider Vinegar have been blended together with certified organic Shea Butter to create a rich formula which gently smooths porous, rough or hair over-processed from color treatments or perms. SheaMoistures High Porosity Moisture-Seal Shampoo is formulated with ultra-hydrating
The Test: Many, many people on the internet have tried simple tests for porosity. Of all the methods I have seen, I think the following method gives you most accurate results. To determine your hair porosity level using water, spritz a small section of curls with water and watch how your hair reacts - does your hair absorb the water quickly (indicating high porosity) or does it remain on top (indicating a low porosity level).. Normal Porosity: These are the lucky curls. It accepts and retains moisture inside the cuticle. The curls are full of bounce and elasticity and hold styles well. This hair can be dyed easily, and usually requires very little maintenance. Avoid using heat styling tools. When you do use hot tools, use a thermal protectant. Natural or Sulfate-free shampoos and conditioners are good to use. Leave in conditioners can be used to cure fly-aways.. High porosity: I used to have highly porose hair. High porosity hair can be a real pain. Symptoms of high porosity hair could be that ...
Dupont, Thomas, Leclaire, Philippe et Panneton, Raymond. 2013. « Acoustic methods for measuring the porosities of porous materials incorporating dead-end pores ». Journal of the Acoustical Society of America, vol. 133, nº 4. pp. 2136-2145 ...
When a porosity problem occurs, you first need to determine the type of porosity. Porosity is symbolized in phi (Ï ) and its value is expressed in percentage. And that means that women with high porosity hair will find that their hair responds well to many different types and sizes of proteins. High porosity values indicate high capacities of the reservoir rocks to contain these fluids, while low porosity values indicate the opposite. Similarly, the definitions of the standard densities associated with rocks then follows: Typically porosity is a limited space devoid of metal where gas was trapped during solidification. Factors Affecting Porosity of Soil. Types of Pores in Soil 3. Unless otherwise ascribed many of the other diagrams and the photomicrographs were created by Christopher Kendall. The porosity classification guide can help you determine the porosity type. They can do protein treatments more often and see beautiful hair from it. The bulk of mineral content is made of clay, silt and sand,
You should also note that:. Even though your hair may be predominantly one type of porosity, some strands would be a different porosity. Secondly, one strand may be one porosity at the roots and another at the ends. For example, I think my hair is mostly high porosity but there might be some normal porosity strands. I have also noticed that my roots are normal porosity but my ends are high porosity. Hair care can be so confusing! In my next post, I will be talking more in-depth about determining your hair porosity and after that managing each of the porosity types. ...
In a disposable absorbent garment, an absorbent structure includes liquid absorbing material comprising an upper layer comprising preferably softwood fibers and having a density from about 0.03 to about 0.14 g/cc, a lower layer comprising preferably hardwood fibers, formed substantially separately from and underlying at least a portion of the upper layer, the second layer having top and bottom surfaces, a density from about 0.14 to about 0.3 g/cc, a total void volume greater than about 80%, an average pore size distribution generally less than the average pore size distribution of the upper layer. There is an overlap in the pore size distributions of the upper and lower layers such that the smallest pores in the upper layer are smaller than the largest pores in the lower layer and front and rear fluid storage pouches, preferably spaced from one another at the front one-third and rear one-third of the absorbent structure, respectively, each pouch comprise superabsorbent material disposed in a hydrophilic
In this communication, we present a novel approach for control of drug release from porous materials. The method is based on deposition of a plasma polymer layer with controlled thickness which reduces a pore diameter and, hence, defines the rate of drug release.
The transport of electrolytes across varying section channels or porous material is of paramount importance due to its relevance in diverse fields spanning from biology to oil extraction. Clearly in these scenarios the shape of the porous media or the ionic channel is crucial in determining the transport properties of the electrolyte, or viceversa, for every channel shape it is possible to identify an optimal protocol that maximizes the transport. In this seminar, we will present a simplified approach capable of capturing the role of the shape of the container in the overall transport. By means of our simplified approach we will show that novel dynamical regimes can be attained when the Debye length is comparable to the channel bottleneck. ...
Porous Materials Incorporated has six product lines and manufactures over thirty different instruments. In addition, we hold several US and International patents on novel technology for characterization of pore structure. ...
Numerical simulation with progressive damage criterion is implemented to investigate the effect of porosity on the bending properties of 2D cross-ply carbon/carbon (C/C) composites. The mechanical properties of Pyrocarbon matrix regarding the change of porosity are calculated by using Mori-Tanaka approach. Combining with the stiffness degradation scheme, the ultimate bending strengths are calculated in Abaqus though a user-defined subroutine (USDFLD). Delamination is modelled by inserting cohesive elements between two adjacent plies. A good agreement is obtained when the FEM results are compared to three-point bending experiments. The FEM results show that the bending strength decreases greatly with the increase of porosity. When the porosity reaches up to 18%, the bending strength is decreased by 57%. The major fracture behaviors are interlamination delamination and continuous crack damage in 90° plies. With the increase of porosity, more severe interlamination delamination will be slightly ...
Summary: The aim of this paper was to investigate and analyze microwave and convection drying kinetics of porous materials on laboratory scale. A wet clay plate was chosen as a representative of porous materials. General statements as regards a drying process, whether on a theoretical or analytical level, phenomenological or empirical, still presents on open issue. This is specially true for microwave drying. Modelling was based on elementary layer theory adapted to practical cases of wet plates drying of porous materials both in a laboratory convection dryer and laboratory test apparatus for microvave drying. During the drying process of shaped porous materials, it is inevitable to have knowledge of maximum allowed drying rate curve which can be only obtained by experimentation. Taking this into account special attention was payed to finding out the maximum allowed drying rate curve both for convection and microwave drying. It is, thereby, necessary to have a model that can sufficiently ...
This innovative reference collects state-of-the-art procedures for the construction and design of nanoparticles and porous material while suggesting appropriate
Mercury intrusion porosimetry is a valuable method for characterizing relative pore space dimensions. This dynamic technique is based on the intrusion of mercury into a porous structure under stringently controlled pressures. Mercury intrusion porosimetry permits the calculation of numerous sample properties such as pore size distributions, total pore volume, total pore surface area, median pore throat diameter, and sample densities (bulk and skeletal).. Capillary behavior and permeability are critical to reservoir behavior. Porosimetry is among the few techniques capable of probing the fine connected pore space of shales. This method is particularly useful in evaluation reservoir quality variations within a shale play and in petrotyping shale (Kale et al., 2010, Society of Petroleum Engineer).Various empirical transforms can be applied to estimate permeability from mercury intrusion data. While not quantitative, these estimates can provide a relative assessment of the variation in permeability. ...
Finden Sie alle Bücher von Fleys Matthieu - Water Behavior in Hydrophobic Porous Materials. Bei der Büchersuchmaschine können Sie antiquarische und Neubücher VERGLEICHEN UND SOFORT zum Bestpreis bestellen. 9783639091427
Disclosed herein are textured nonwoven wiper materials. The textured nonwoven wiper material includes a meltblown nonwoven web material that has a first exterior surface and a second exterior surface, and at least the first exterior surface of the meltblown nonwoven web is a three-dimensional textured surface. The textured meltblown nonwoven web has a multi-modal pore size distribution that includes at least two major pore size peaks.
INTENDED USE: Nanoil For High Porosity Hair is one of the three oils available in the range. The high porosity version is designed to rebuild, moisten, beautify and protect dry, damaged hair. Nanoil will also take care of the dry sensitive and irritated scalp. COMPOSITION AND EFFECTS: Nanoil nourishes the scalp and bulbs and the […]
Shape-Anchored Porous Polymer Monoliths for Integrated Online Solid-Phase Extraction-Microchip Electrophoresis-Electrospray Ionization Mass Spectrometry ...
S. Inagaki, Y. Fukushima, Hikaru Doi, O. Kamigaito; Pore size distribution and adsorption selectivity of sepiolite. Clay Minerals ; 25 (1): 99-105. doi: Download citation file:. ...
The effect of the pore size distribution on size-resolved filtration efficiency was investigated for two ceramic particulate filters using
Causse, P. et Trochu, F.. 2018. « Combined characterization of pore size distribution and permeability in fibrous textiles by capillary flow porometry ». In 14th International Conference on Flow Processing in Composite Materials (Lulea, Switzerland, May 30 - June 01, 2018 ...
The present invention provides a porous thermal regenerator apparatus and method of making a porous thermal regenerator comprised of metallic or intermetallic particles that are held together in a porous three dimensional network by a binding agent (such as epoxy). One aspect of the apparatus is that the porosity of the porous thermal regenerator is greater than the tapped porosity of the particles comprising the porous thermal regenerator; moreover, the high-porosity apparatus is durable, that is, it remains intact when exposed to strong time-varying magnetic forces while immersed in aqueous fluid. This high porosity, when combined with high strength and aqueous heat transfer fluid stability, leads to improved porous thermal regenerators and concomitantly to magnetic refrigerators with improved performance.
Porosity sealing , is the process of filling a porous substrate to make it airtight . Porosity is sealed through the process of vacuum impregnation . Vacuum impregnation is the preferred method for sealing parts to prevent fluids or gases from leaking under pressure. Vacuum impregnation seals porosity and leak paths that form during the casting or molding process. It does so without changing the castings' dimensional or functional characteristics and allows manufacturers to use parts that would otherwise be scrapped. There are three types of porosity; Flow Porosity, Gas Porosity and Shrink Porosity. Porosity is found in many cast metal components, but it commonly found in aluminium and magnesium die castings. Process Porosity sealing is a four-step process: In the impregnation chamber (also known as an autoclave, pressure vessel or vacuum vessel) air is evacuated from the leak path in the part by using a deep vacuum. The evacuated leak path is filled with sealant by covering the part with the
The influence of porosity on the superconducting properties have been investigated on YBa/sub 2/Cu/sub 3/O/sub 7/ thin films deposited on LaAlO/sub 3/ [100] substrates by the so-called Trifluoroacetate (TFA) route. Micro-Raman spectroscopy have been used to determine the concentration of c-axis grains /spl delta/ in different samples and their influence on the final film porosity as observed from SEM imaging. This has been compared with measurements of resistivity and critical currents in the same samples. We prove that this /spl delta/ fraction is the main parameter controlling the porosity and hence the normal-state resistivity of the thin films. The optimization of the microstructure of these YBa/sub 2/Cu/sub 3/O/sub 7/ TFA films allow to have high critical currents : J/sub c/ = 3 /spl times/ 10/sup 6/ A/cm/sup 2/ at 77 K ...
We present here some evidences that capillary liquid bridges are able to deform micrometric cylindrical pores by tensile stress. Brine-soaked filter membranes are submitted to drying conditions leading to NaCl precipitation inside the 5-10 μm pores. A close examination demonstrated that two forms of NaCl crystallites are successively generated. First, primary cubic crystals grow, driven by the permanent evaporation. When this angular primary solid gets near the pore wall, while the evaporation makes the pore volume to be partly invaded by air, capillary liquid can bridge the nowsmall gap between the halite angles and the pore wall. In a second step, these small capillary bridges are frozen by a secondary precipitation event of concave-shaped NaCl. The proposed interpretation is that the liquid capillary bridges deform the host matrix of the membrane, and the situation is fossilized by the growth of solid capillary bridges. A quantitative interpretation is proposed and the consequences towards the
TY - JOUR. T1 - Controls on primary porosity and permeability development in igneous rocks. AU - Petford, Nick. PY - 2003. Y1 - 2003. N2 - Some of the more important processes leading to the development of primary igneous porosity due to the cooling and crystallization of magma are reviewed. A distinction is made between volcanic and plutonic rocks, and crystalline and granular volcanic material. Porosity in each rock type is classified according to a proposed effective length scale and geometry into diffusive (Class D) and macroscopic flow (Class F) features. Estimated ranges in values of porosity and permeability are given for a wide selection of igneous rock types, and comparison is made with permeability variations (Δk) derived for both the continental and oceanic crust. While fracture porosity is dominant in most crystalline materials, primary porosity development may play an important role in the final (total) porosity in igneous basement. Some types of primary porosity and permeability ...
Use of Capillary Pressure Data and Log Calculated Water Saturation for the Characterization of Dual Porosity, Dual Permeability Systems. This paper describes a simple method to divide the effective porosity values that can be calculated from log analysis into two flow media (fracture and matrix) pore volumes for use in numerical simulation models. The division of the porosity is based on the assumption that the total porosity of the system is made up from two contributing rock types or lithofacies that have distinct pore size and/or pore size distribution such that they can be represented by different capillary pressure functions. This assumption is applicable to the non-fractured as well as to the fractured systems.. When the method is used for the fractured systems, the fracture is typically represented by a zero capillary pressure value (gravity segregation). The matrix has its own laboratory measured capillary pressure curve. Based on a predetermined water-hydrocarbon contact and using the ...
American Society for Testing and Materials (1999) Standard Test Method for Determination of Pore Volume and Pore Volume Distribution of Soil and Rock by Mercury Intrusion Porosimetry, Designation D 4404-84 (Reapproved 1992). Annual Book of ASTM Standards, 04.08, 588-592.
A porous object includes a porous material having internal pore surfaces and external pore surfaces. Releasing material encapsulated biomolecules are immobilized on at least one of the internal pore surfaces, at least one of the external pore surfaces, or combinations thereof.
The present invention provides biosensor test devices for measuring the presence or amount of an analyte in a biological fluid. The devices have a base plate that has an electrode system embedded therein, and a hydrophilic porous material situated on the base plate. A hydrophobic protective layer is situated on the hydrophilic porous material, and a cover is placed on the hydrophobic protective layer to complete the device. Some embodiments also use an insulating layer, which can be situated between the base layer and the hydrophilic porous material. The cover of the device has an opening present therein, situated over the electrodes, so that the electrodes communicate with the exterior of the device through the groove. The insulating layer can also have a groove situated therein, which in one embodiment is placed to align with the groove in the cover. The invention also provides methods of manufacturing the devices, and methods of using them.
Summary: The development of new porous materials is critical to improving important gas storage and separations applications, and will have a positive impact on reducing greenhouse gases. This includes the deployment of methane and/or hydrogen gases as alternative fuels, development of new filters for removing trace gaseous contaminants from air, and separation of carbon dioxide from flue gas to mitigate greenhouse emissions from the burning of fossil fuels. Dr. Wilmers grant will enable his lab to utilize computational methods to probe the limits of material performance for physical adsorption to porous materials. Although past computational screening has suggested physical limits of adsorption capacity for metal-organic frameworks (MOFs), this project will explore the novel use of so-called pseudomaterials, which represent all potential atomistic arrangements of matter in a porous material ...
Meso-Architecture Block Copolymers with High Surface Area Styrene-Bridged Organosilica Particles as Constituent for the Stimuli-Responsive Remediation of Water
The volume of the voids of a soil over the total volume of the sample defines the porosity of a soil. Used in geology, hydrogeology, soil science, and building science, the porosity of a porous medium (such as rock or sediment) describes the fraction of void space in the material, where the void may contain. Porosity is a fraction between 0 and 1, typically ranging from less than 0.01 for solid granite to more than 0.5 for peat and clay. It may also be represented in percent terms by multiplying the fraction by 100. Porosity is the ratio of pore volume to its total volume. Porosity is controlled by: rock type, pore distribution, cementation, diagenetic history and composition. Porosity is not controlled by grain size, as the volume of between-grain space is related only to the method of grain packing.
Hair that has a high porosity tends to have raised cuticles and the hair too-readily absorbs moisture. Overly-porous hair also releases moisture easily, thus; becoming dry and prone to damage. Perms and straighteners will process much faster in high-porosity hair. Having highly porous hair does not mean your hair is damaged, it just means you have to use different methods when taking care of it ...
Polymer-derived nanoporous carbon materials with high thermal stability, high surface area and narrow pore size distribution have been widely used as catalyst supports. Catalyst performance (activity and selectivity) is significantly affected by the pore size and porosity of the carbon support. Mass transfer limitation inside the pores and steric hindrance imposed by the pore walls can enhance catalyst selectivity and alter reaction kinetics. In this study, platinum embedded in nanoporous carbon spheres was used as a shape selective catalyst for liquid phase hydrogenation of alkenes. Experimental data obtained for different synthesized catalysts with different porosity and pore sizes were used to estimate kinetic parameters (Langmuir-Hinshelwood) and diffusion coefficients for different reactants and products inside the pores, using numerical solution of reaction-diffusion equation. It was shown that adsorption equilibrium constants and reaction rate constants are larger inside the nanopores of ...
The consolidation and permeability characteristics of high porosity surficial sediments from the Coastal Benthic Boundary Layer (Naval Research Laboratory) Special Research Program test site in the EckemfOrde Bay Baltic Sea were studied using a backpressured, constant rate of deformation (CRD) consolidation and permeability testing system driven by flow pumps The silty clay sediments from the Baltic test site are characterized by high void ratios (above 6), large organic content and dissolved or free methane gas bubbles. The high organic content (up to 17%) influences several of the unique features of these sediments including high water contents (up to 500%; porosities up to 93%), high consistency limits and high compressibility. The sediments are dominated by clay and silt size fractions (42% and 55% respectively) with a small percentage (3%) of sands. Organic content determinations performed on selected samples indicated a variation from 9% to 17% in the organic fraction (dry weight basis). Atterberg
PRO-MIX® HP, with its high perlite content, provides a growing environment which benefits growers looking for significant drainage capacity, increased air porosity and lower water retention. The added benefit of a fibrous peat moss and coarse perlite makes this formulation ideal for growers demanding a superior quality product adapted to their needs for watering flexibility and crop seasonality. HP=high porosity. ...
A matrix including: a) a polymeric base matrix including macropores (pore system 1) and b) an interior material, possibly porous (pore system 2), retained within the macropores. The matrix is characterized in that there is a continuous free volume between the interior material and the pore walls of the macropores. A method for manufacturing a matrix including a base matrix having macropores in which an interior material is located. The method is characterized in including the steps: (I) providing a base matrix having macropores; (ii) filling the macropores with a soluble form of the interior material; (iii) transforming the insoluble from to an insoluble form; (iv) shrinking the insoluble form; and (v) irreversibly stabilizing the material in its shrunken form. The matrix can be used in separation methods, cell culturing, solid phase synthesis of organic molecules, and in catalytic reactions (such as enzyme reactions) and other uses in which porous support matrices are used.
TY - JOUR. T1 - Prediction of pores formation (porosity) in foods during drying. T2 - Generic models by the use of hybrid neural network. AU - Hussain, M. A.. AU - Shafiur Rahman, M.. AU - Ng, C. W.. PY - 2002/2. Y1 - 2002/2. N2 - General porosity prediction models of food during air-drying have been developed using regression analysis and hybrid neural network techniques. Porosity data of apple, carrot, pear, potato, starch, onion, lentil, garlic, calamari, squid, and celery were used to develop the model using 286 data points obtained from the literature. The best generic model was developed based on four inputs as temperature of drying, moisture content, initial porosity, and product type. The error for predicting porosity using the best generic model developed is 0.58%, thus identified as an accurate prediction model.. AB - General porosity prediction models of food during air-drying have been developed using regression analysis and hybrid neural network techniques. Porosity data of apple, ...
where np and ns refer to the refractive index of the porous material and solid material, respectively, and p is the porosity of a porous material. However, it is difficult to measure the pore size, grain size, and porosity of the film as the thickness is only tens to a hundred of nanometers. Most of the reported porosity measurement methods are calculated or analogical. For example, Orignac et al. [22] reported the porosity volume fraction Vp is estimated as the ratio between the sum of the areas of the pores measured in the SEM image and the total imaging area of the sample. Xiao et al. [23] measured the reflective index based on the relationship between the reflective index and acid- or base-catalyzed sol ratio. They found the refractive index of the mixed AR films is proportional to the acid- to base-catalyzed sol ratio. With an acidic catalyst, the growth of silica sol tends to form linear chains, giving the acid-catalyzed AR film a refractive index of 1.44. By mixing the base-catalyzed and ...
Secondary porosity n sandstones can be classified according to origin and pore texture. Five significant genetic classes of secondary porosity are defined by processes of origin: Fracturing; shrinkage; dissolution of sedimentary grains and matrix; dissolution of authigenic pore filling cement; and dissolution of authigenic replacive material. This publication provides information on the genetic-textural classes of secondary sandstone porosity; the textural spectrum of secondary sandstone porosity; the recognition of secondary sandstone porosity; the geological occurrence and diagenetic origin of secondary sandstone porosity; the textural stages of sandstone mesodiagenesis; the diagenesis of quartz arenites; the diagenesis of sandstones of intermediate and low mineralogical maturity; examples of porosity distribution, and reservoir aspects. ...
All about Effect of shrinkage porosity on mechanical properties of steel casting sections by G. K. Turnbull. LibraryThing is a cataloging and social networking site for booklovers
"Occupy Porosity." OnlineOpinion, April 2012. "2012 and Indigenous Fantasy." Fortean Times, February 2012. "Interview with ...
Porosity and environmental absorbent potential[edit]. Because of the small size of individual nanocrystals, Fh is nanoporous ...
Porosity[edit]. Coalbed methane reservoirs are considered as a dual-porosity reservoirs. Dual porosity reservoirs are ... The porosity of a coalbed methane reservoir can vary from 10%-20 %; However, the cleat porosity of the reservoir is estimated ... As production occurs from a coal reservoir, the changes in pressure are believed to cause changes in the porosity and ... McKee, C. R., Bumb, A. C., & Koenig, R. A. (1988, March 1). Stress-Dependent Permeability and Porosity of Coal and Other ...
ΦT - Total porosity (PHIT), which includes the pore space in sand and shale. Sw - Total water saturation, the fraction of the ... Porosity: ϕ {\displaystyle \phi } (Anti=tattilization)The percentage of a given volume of rock that is pore space and can ... Φsh - Shale porosity. Volumetric fraction of pore space in shale. These pore space is filled with bounded water by definition. ... Φe - Effective shale corrected porosity which includes only the pore space in sand. The pore space in shale which is filled ...
Soil porosity is complex. Traditional models regard porosity as continuous. This fails to account for anomalous features and ... The porosity of a soil is an important factor that determines the amount of water a soil can hold, how much air it can hold, ... Porosity of topsoil is a measure of the pore space in soil which typically decreases as grain size increases. This is due to ... Porosity of a soil is a function of the soil's bulk density, which is based on the composition of the soil. Sandy soils ...
Zajíček, L. (1987-1988). "Porosity and σ-porosity". Real Anal. Exchange. 13 (2): 314-350. ISSN 0147-1937. MR943561. ... The relationship between porosity and being nowhere dense can be illustrated as follows: if E is nowhere dense, then for x ∈ X ...
This means that a sonic log can be used to calculate the porosity, confining stress, or pore pressure of a formation if the ... Many relationships between travel time and porosity have been proposed, the most commonly accepted is the Wyllie time-average ... porosity. The accuracy of modern compressional and shear sonic logs obtained with wireline logging tools is well known now to ... most notably decreasing with an increasing effective porosity and increasing with an increasing effective confining stress. ...
Whether a bed is hard or soft depends on the porosity and pore pressure; higher porosity decreases the sediment strength (thus ... Porosity may vary through a range of methods. Movement of the overlying glacier may cause the bed to undergo dilatancy; the ... A soft bed, with high porosity and low pore fluid pressure, allows the glacier to move by sediment sliding: the base of the ... This increases the porosity. Unless water is added, this will necessarily reduce the pore pressure (as the pore fluids have ...
The increased rate is a result of the greater surface area associated with porosity. Porosity produces rougher absorber ...
... porosity decreasing impregnation of concrete; manufacture of acid-resistant cement; Glasswork and cerarnics: antireflection ...
Reduces weld porosity in copper. Argon-hydrogen H-2 (98% argon/2% hydrogen) H-5 (95% argon/5% hydrogen) H-10 (80% argon/20% ... Sulfur hexafluoride can be added to shield gas for aluminium welding to bind hydrogen in the weld area to reduce weld porosity ... More than 5% oxygen makes the shielding gas oxidize the electrode, which can lead to porosity in the deposit if the electrode ... Increased oxygen makes the shielding gas oxidize the electrode, which can lead to porosity in the deposit if the electrode does ...
Gas solubility and porosity" (PDF). Georgia Institute of Technology. Archived from the original (PDF) on 14 January 2015. ... because if the riser solidifies first then defects like shrinkage or porosity can form. Chvorinov, Nicolas (1940). "Theorie der ...
Porosity is a measure of how the paper responds to a liquid. There are several popular stamp collecting terms. On-paper refers ... Porosity is a characteristic of paper. Wood fibers are hydrophilic or water loving. Sizing is added to paper to create a ...
doi:10.1007/s11208-005-0033-2. D. T. Britt; D. Yeomans; K. Housen; G. Consolmagno (2002). "Asteroid density, porosity, and ...
Birchall, J. D.; Howard, A. J.; Kendall, K. (1981). "Flexural strength and porosity of cements". Nature. 289 (5796): 388. ... "The Relation between Porosity, Microstructure and Strength, and the Approach to Advanced Cement-Based Materials [and Discussion ...
Britt, D. T.; Yeomans, D. K.; Housen, K.; Consolmagno, G. (2002). "Asteroid Density, Porosity, and Structure" (PDF). Asteroids ... Ida would have a porosity of 11-42%. Ida's interior probably contains some amount of impact-fractured rock, called megaregolith ...
Liu C, Zeng C, Luo TY, Merg AD, Jin R, Rosi NL (September 2016). "Establishing Porosity Gradients within Metal-Organic ... Their high surface area, tunable porosity, diversity in metal and functional groups make them especially attractive for use as ... but was the central point to achieve a permanent porosity. (2) The use of the isoreticular principle where the size and the ... "Ultrahigh porosity in metal-organic frameworks". Science. 329 (5990): 424-8. Bibcode:2010Sci...329..424F. doi:10.1126/science. ...
Image analysis can measure porosity, pore-size distribution and volume fractions of secondary phases by ASTM E1245. Porosity ... Grain size, porosity and second-phase content have all been correlated with ceramic properties such as mechanical strength σ by ... Second-phase content and porosity are measured the same way in a microstructure, such as ASTM E562. Procedure E562 is a point- ... Three common quantitative analyses of microstructures are grain size, second-phase content and porosity. Microstructures are ...
Curran, J.A.; Clyne, T.W. (2006). "Porosity in plasma electrolytic oxide coatings". Acta Materialia. 54 (7): 1985. doi:10.1016/ ...
Typically porosity decreases with increasing depth. However, there is an anomalous preservation of porosity at depth at drill ... This has been attributed to post-depositional opal cementation that is preserving the porosity (Spinelli et al., 2007). The ... There are indications of an increase in the retention of porosity within the rock. ...
Centerline porosity and segregation are eliminated. Certain metals and alloys, such as Ti, cannot be melted in open air ...
Materials have a low permeance/porosity. Minimum moisture is absorbed by the materials. **IICRC s500 2016 update adds that ... Involves materials with a very low permeance/porosity, such as hardwood floors, concrete, crawlspaces, gypcrete, plaster, etc. ...
Gregg, S. J.; Sing, Kenneth S. W. (1982). Adsorption, Surface Area, and Porosity (Second ed.). London: Academic Press. ISBN 978 ... "Reporting physisorption data for gas/solid systems with special reference to the determination of surface area and porosity ( ...
This porosity is used to contain lubrication. Tenoplus is a two-stage high-temperature process. The first stage occurs at 625 ° ... Sursulf has a sulfur compound in the salt bath to create surface sulfides which creates porosity in the workpiece surface. ...
This is calculated using the volumetric equation - GRV x N/G x Porosity x Sh / FVF Gross rock volume (GRV) Amount of rock in ... Net/gross ratio (N/G) Proportion of the GRV formed by the reservoir rock (range is 0 to 1) Porosity Percentage of the net ... Net reserve Part of net sand that has the minimum reservoir qualities; i.e. minimum porosity and permeability values. ...
later developed the Controlled-Porosity Osmotic Pump (CPOP) with the intention of addressing some of the issues that led to ... Haslam, John L.; Rork, Gerald S. "Controlled porosity osmotic pump". Google Patents. United States Patent and Trademark Office ...
It contains only about 60-70% solid matter, the remainder being air in the form of porosity. This is turn leads to an ... This is because at porosity percentages above the 'pore percolation threshold', pores link up into continuous channels. The ... Finally, and crucially, their porosity means that they can be infiltrated by materials with useful properties, or processed ... porosity. As we might expect, this amount of air in the component reduces its strength a lot. Pure, fully dense alumina, for ...
doi:10.1140/epjc/s10052-015-3479-5. Gurzadyan, V.G.; Kocharyan, A.A. (2009). "Porosity Criterion for Hyperbolic Voids and CMB ...
This is due to a combination of brecciation (rock lithified from fragments of prior rocks) including porosities and inherently ... C-chondrites are friable, due to both macro-scale porosity and micro-scale matrices of phyllosilicates, with many chondrules ... Chondrites and their Components Britt, D (Jul 2000). "The porosity of dark meteorites and the structure of low-albedo asteroids ... ISBN 0-521-66303-2. Britt, D; Consolmagno, G (August 2003). "Stony meteorite porosities and densities: A review of the data ...
The porosity results in a decrease in both the thermal conductivity of the fuel and the swelling which occurs during use. ... The thermal conductivity of uranium dioxide is low; it is affected by porosity and burn-up. The burn-up results in fission ... Then the thermal conductivity of the porous phase (Kf) is related to the conductivity of the perfect phase (Ko, no porosity) by ...
In metal castings, porosity is typically considered any void found in the casting. Casting porosity can be caused by gas ... If the porosity is not sealed, fluids may bleed out and negatively affect the finish. Sealing the porosity before secondary ... Porosity is inherent to most manufacturing processes. Porosity is only considered a defect if it is interconnected and creates ... Casting defects caused by porosity can affect the parts structural integrity, creating a failure point. Porosity can also ...
That is: Effective porosity = Total porosity − CBW {\displaystyle {\text{Effective porosity}}={\text{Total porosity}}-{\text{ ... Effective porosity ϕ e 3 {\displaystyle \phi _{e3}} Total porosity minus clay-bound water (CBW). Effective porosity ϕ e 4 {\ ... "total porosity" (notwithstanding comments in ). This core total porosity will generally be equivalent to the total porosity ... this definition of effective porosity equates to total porosity. Total porosity The volume of the reservoir rock which is fluid ...
Source for information on oomouldic porosity: A Dictionary of Earth Sciences dictionary. ... ... ... "oomouldic porosity ." A Dictionary of Earth Sciences. . 16 Oct. 2020 ,,. ...
Porosity: A major problem in castings, porosity is principally caused by the shrinkage that accompanies solidification. Molds ... Porosity is the fraction of the volume of an apparent solid that is actually empty space. Owing to porosity, the surface area ... In metallurgy: Porosity. A major problem in castings, porosity is principally caused by the shrinkage that accompanies ... is attributable to their high porosity and permeability. Porosity is the volume percentage of "void" (actually fluid- or air- ...
... complemented by the Ga+ FIB method which is now frequently used to characterise porosity and organic/inorganic phases, together ... Hierarchical integration of porosity in shales. *Lin Ma. ORCID:,2. , ... A) Porosity-associated phases and corresponding pore types. (B,C) Pore size distribution displayed respectively by number ... PFIB-imaged porosity was measured to be 4.6%, with the largest pore size being 1756 nm in diameter, but no continuous pore ...
The equivalent porosity method (King and Roig, 1988;... Normal Modes of a Poroelastic Soil Layer on a Rigid Bed Rock Sound ... The Use of an Equivalent Porosity Method to Model Flow in Marshes Two dimensional modeling of marshes under unsteady flow ... Transition from High-Porosity to Filled Particulates: Effective Medium Modeling Numerical Study on Effects of Leakage from ... Flow and Transport Simulation in Yucca Mountain Using Dual-Porosity Model Hydraulic Conductivity of Organomodified Soil ...
25 - How can porosity form in a weld and not be seen by...Ch. 25 - What welding process can cause porosity to form?Ch. 25 - How ... Mechanical EngineeringWelding: Principles and Applications (MindTap Course List)How is piping porosity formed? ... is piping porosity formed?. Ch. 25 - What are inclusions, and how are they caused?Ch. 25 - When does inadequate joint ...
The porosity and permeability of the caved zone (gob) in a longwall operation impact many ventilation and methane control ... Mining Publication: Prediction of Porosity and Permeability of Caved Zone in Longwall Gobs. Keywords: Gases Gobs Longwall ... Thus, there has always been debate on the likely values of porosity and permeability of the caved zone and how these values can ... The results suggest that the gob porosity and permeability values can be predicted by this approach and the presented models ...
Catalyst Porosity Testing: Catalyst porosity can be characterised by adsorption isotherms, usually with nitrogen. Apart from ... Measurement of catalyst surface area and porosity. Intertek measures catalyst surface area, porosity and other important ... We provide world-class expertise in both catalyst surface area analysis and catalyst porosity testing. Catalyst Surface Area ... Electron microscopy (SEM and TEM) can be very helpful in understanding the nature of the catalyst porosity and any blockages, ...
If in the shape of rounded holes, the gas is called spherical porosity or just porosity. However, if elongated the terminology ... Fig 1: Porosity in Welds With the advent of fitness-for-purpose acceptance criteria, more and more pressure is being put on NDT ... The effect of porosity on the weld strength is a much-debated topic, but generally it is acknowledged to be over rated and its ... Porosity in welding is a result of dissolved gases or gases released during the welding process, being trapped in the metal ...
Drawing of soil porosity.. Source: ... Retrieved from "" ...
I Decided to do the porosity test to find out what kind of porosity my hair had.... I did both tests described in the Hair ... 1: Hair Porosity!!. Hey Everyone, im sort of a rookie to Naturally i cant even begin to tell you just how long it ... 2c /3a F /Mii, low porosity. Go To Products /Routine:. Clarifying: Suave Essentials Strawberry. Low Poo: Renpure Luxurious ... Do i have High porosity or Low porosity?? Im super Confused! ... 2b wavy, medium texture, low porosity, med-high density. ...
The inner surface of the resulting PTFE tube exhibits a different porosity than the outer surface of the tube; the porosities ... Porosity of the inner and outer surfaces is varied by changing, in the respective billets, the lubrication level and/or the ... surface of expanded PTFE material having a first porosity and an outer surface of expanded PTFE material having a porosity ... A dual porosity PTFE tube including an inner ... The porosity of the inner surface and the porosity of the outer ...
In this work, results of the porosity control in the Ti-13Nb-13Zr alloy produced by powder metallurgy are presented. The ... Citation: Henriques, V., Cairo, C., Galvani, E., Bressiani, J. et al., "Porosity Control in Ti-13Nb-13Zr Alloy Produced by ... Porosity Control in Ti-13Nb-13Zr Alloy Produced by Powder Metallurgy 2006-01-2545. ... It was shown that the porosity level depends on the compaction pressures, sintering temperatures and holding times. ...
An underground porosity reservoir includes substantially impermeable barriers and an aquiclude surrounding a volume of alluvial ... The porosity reservoir of claim 15 wherein the conduit is positioned to run adjacent to the recharge well. 17. The porosity ... The porosity reservoir of claim 17 wherein the conduit is positioned to run adjacent to the extraction well. 19. The porosity ... The porosity reservoir of claim 10, wherein the conduit comprises a perforated pipe. 12. The porosity reservoir of claim 11, ...
Evaluations of porosity relevant to hydrocarbon storage capacity in kerogen-rich mudrocks (i.e., source rocks) have thus far ... Estimation of kerogen porosity in source rocks as a function of thermal transformation: Example from the Mowry Shale in the ... Evaluations of porosity relevant to hydrocarbon storage capacity in kerogen-rich mudrocks (i.e., source rocks) have thus far ... This mode of porosity likely evolved with the thermal transformation of labile kerogen and probably neither depends nor ...
... and so the ones of the greatest porosity. ... in their syntheses leads to significant changes in porosity and ... The membrane porosity was evaluated from (1): where is the mass of a wet membrane sample, is the mass of dry state membrane ... 2.3.1. Porosity and Equilibrium Water Content. The membrane porosity was determined by the mass loss of wet membrane after ... Metals Ions Removal by Polymer Membranes of Different Porosity. Katarzyna Jasiewicz. 1 and Robert Pietrzak. 1. 1Laboratory of ...
Porosity in welds reduces the strength and integrity of the weld. As will be described in more detail below, porosity can occur ... 7. A method of welding a material subject to formation of porosity due to hydrogen comprising: a) providing a cavity in fluid ... 1. A method of welding a material subject to formation of porosity due to hydrogen comprising: a) creating an arc; b) ... A welding system comprising: a weldment made of a material subject to formation of porosity due to hydrogen; welding equipment ...
Porosity is of great industrial concern as it influences the behavior of gas adsorption and fluid flow within materials. ... channels or interstices may be regarded as porous Porosity influences the physical exchanges and chemical reactivity of solids ... Porosity Instruments. Any solid material that contains cavities, channels or interstices may be regarded as porous. Porosity ... Porosity is of great industrial concern as it influences the behavior of gas adsorption and fluid flow within materials. ...
Equalize porosity and return hair to a balanced state for increased smoothness and vibrancy with Roux Rejuvenating Porosity ... Equalize porosity and return hair to a balanced state for increased smoothness and vibrancy with Roux Rejuvenating Porosity ... Equalize porosity and return hair to a balanced state for increased smoothness and vibrancy with Roux Rejuvenating Porosity ... Rated 5 out of 5 by Sharinaji from Porosity control corrector confitioner The best to mix with any color to cool down your ...
This increase in porosity was confirmed by comparing two adsorbents with respect to their gel-filtration properties. g I_ 7. ...
Low porosity titania forms containing only a small amount of hydroxyl groups and possessing a high refractive index which are ... This low porosity property resulting from the instant method is novel in sol-gel produced titania films. This low porosity ... Low porosity titania forms containing only a small amount of hydroxyl groups and possessing a high refractive index which are ... Low porosity titania forms containing only a small amount of hydroxyl groups and possessing a high refractive index which are ...
I. Algaba, A. Riva, and P. C. Crews, "Influence of fiber type and fabric porosity on the UPF of summer fabrics," AATCC Review, ... Investigating the Relationship between Knitted Fabric Porosity and Light Permeability. Manoj Kumar Imrith, Roshan Unmar, and ...
Wholesale Various High Quality Porosity Metal Products from Global Porosity Metal Suppliers and Porosity Metal Factory,Importer ... Tags: Porosity Metal , Multi Porosity Metal , Microns Porosity Metal , View larger image ... Tags: 4 High Porosity Grinding Wheel , 4 High Porosity Grinding Wheel For Metal And Stainless Steel , View larger image ... Tags: Low Porosity Stainless Steel Wire Mesh , High Quality Low Porosity Stainless Steel Wire Mesh , High Quality 2016 New ...
Torbjorn Mathiesen, Chief Technology Officer of Novus Scientific writes an article entitled, Flexibility, Porosity Design ... STORY in Medical Design Technology: Flexibility, Porosity Design Leads to Regeneration of Soft Tissue. News • Sep 30, 2014 14: ... It also creates well defined porosity in TIGR which is so important for tissue regrowth and anchorage of the product. ... Read the article as seen in Medical Design Technology here: ...
Four different soil samples show the relationships between particle size, shape, and uniformity with porosity and permeability ... Carolina® Soil Porosity and Permeability Kit. Item # GEO778 Exclusive *bvseo_sdk, java_sdk, bvseo-4.0.0 ... Four different soil samples show the relationships between particle size, shape, and uniformity with porosity and permeability ... Four different soil samples show the relationships between particle size, shape, and uniformity with porosity and permeability ...
Attention to soil structure is crucial in achieving good soil porosity. A look at a few basic soil types helps the gardener ... Water and air communicate through soil as a result of porosity.. Importance. Soil porosity affects drainage, allowing soils to ... They have poor soil porosity and do not let water drain. Aeration is poor and many plants decline and die in these non-porous, ... Poor porosity facilitates erosion of soils as rainwater washes particles off the surface rather than penetrating into soil. ...
Have you ever heard about using so-called porosity function to describe boundary conditions in case when the physical boundary ... Have you ever heard about using so-called porosity function to describe boundary conditions in case when the physical boundary ... you may assume that they have a staircase geometry or use the porosity function or ..... Have anybody of you tried the ...
1: Oils and low porosity hair. Just wanted to hear your feedback re: using oils in your hair? Do you use hot oil treatments ... 2B/C-3A) fine - low porosity. Routine:. Wash: Daily Fix,SMT, Kesham, Urtekram. RO: Motions CPR Li, Inecto Cocos co, AO GPB, ... 2B/C-3A) fine - low porosity. Routine:. Wash: Daily Fix,SMT, Kesham, Urtekram. RO: Motions CPR Li, Inecto Cocos co, AO GPB, ... 3a/3b, Low porosity, Medium Density Low-poo: Shea Moisture Moisture Retention. RO: Matrix Biolage Conditioning Balm. Leave-in: ...
  • Five years later and the team are celebrating the official completion of the Sliced Porosity Block, a LEED Gold complex which offers a smooth blend of quality real estate and unrestricted public space. (
  • Steven Holl Architects' Sliced Porosity Block is the latest completed addition to Chengdu's ever-growing skyline. (
  • Inspired by Du Fu, a local poet of the Tang Dynasty, the contemporary design studio drew on a specific poem for the design of the Sliced Porosity Block which reads: "From the northeast storm-tossed to the southwest, time has left stranded in Three Valleys. (
  • Whilst enlivening the development from an aesthetic aspect, these three water features also play an active role in the sustainability element of the Sliced Porosity Block. (
  • In total, the Sliced Porosity Block measures 3 million sq ft and offers serviced apartments, retail units, a hotel, café and various restaurants but it is the generous open public spaces that sets the design apart. (
  • In the center of Chengdu, China, at the intersection of the first Ring Road and Ren Ming Nam Road, the Sliced Porosity Block forms large public plazas with a hybrid of different functions. (
  • The Sliced Porosity Block is heated and cooled with 468 geothermal wells and the large ponds in the plaza harvest recycled rainwater, while the natural grasses and lily pads create a natural cooling effect. (
  • The recently completed Sliced Porosity Block in Chengdu has been named Mixed-Use Building of the Year in the 2013 Emirates Glass LEAF Awards. (
  • The Sliced Porosity Block, they said, "responds very well to the need to achieve new levels of green construction in Chengdu, with a complex that is heated and cooled geothermally by 400 wells. (
  • The Sliced Porosity Block is heated and cooled geo-thermally with 468 wells at 90 meters deep. (
  • This is the Sliced Porosity Block, an inner-city mixed-use project by Steven Holl in Chengdu, China. (
  • The Sliced Porosity Block becomes a bright white backdrop to everyday life. (
  • The Sliced Porosity Block is a development by CapitaLand, one of the biggest developers in Asia rapidly developing its portfolio in China. (
  • The Sliced Porosity Block tells the whole story of a rapidly transforming country. (
  • If we skip this step our porosity will be too uniform, losing realism. (
  • In unconsolidated sands, better sorting systematically increases both permeability and porosity. (
  • In the Permeability, Porosity and Soil Moisture Laboratory Kit for environmental science, determine the permeability and porosity of soil by measuring how easily air and water move through soil. (
  • In this kit, students determine the permeability and porosity of soil by measuring how easily air and water move through soil, and the volume of air and water the soil will hold respectively. (
  • Permeability and porosity decrease with increasing net stress in consolidated and unconsolidated porous media is a well-known phenomenon to petroleum and geomechanics engineers. (
  • Conversely, permeability and porosity are observed to increase when net stress decreases, however typically follow a different path, this discrepancy is known as hysteresis. (
  • The trend of permeability and porosity hysteresis is a signature of porous medium that depends on several physical and mechanical properties. (
  • Understanding permeability and porosity hysteresis plays a significant role in production strategies of hydrocarbon reservoirs. (
  • The reason is that the stress change associated with permeability and porosity hysteresis can affect adsorption/desorption and diffusion transport mechanisms which are among the main driving mechanisms in low or ultra-low permeability reservoirs. (
  • In this study, permeability and porosity hysteresis of nano, micro, and milli-Darcy core samples are measured for a wide range of net stress and the results are correlated with pore structures observed by Field Emission Scanning Electron Microscopy (FE-SEM) images. (
  • This core total porosity will generally be equivalent to the total porosity derived from the density log when representative values for matrix and fluid density are used. (
  • The most common definition of effective porosity for sandstones excludes CBW as part of the porosity, whereas CBW is included as part of the total porosity. (
  • That is: Effective porosity = Total porosity − CBW {\displaystyle {\text{Effective porosity}}={\text{Total porosity}}-{\text{CBW}}} To assess the effective porosity, samples are dried at 40-45% relative humidity and 60 °C. This means that one to two molecular layers of CBW can be retained, and a form of "effective porosity" can be measured on the samples. (
  • total porosity but also how the distribution of porosity evolves with reaction that affects permeability. (
  • This resulted in an ability to tailor and control the important microstructural features including the scale of the microstructure, the macropore size and total porosity. (
  • 1 , 2 Herein, we report the rapid synthesis of customized zeolite monoliths with various compositions and hierarchical porosity (macro-meso-micro) using 3D printing technique. (
  • The 3D-printed zeolite monoliths exhibited hierarchical porosity with pore sizes ranging from 1.5 nm to 1 µm. (
  • The effective porosity is of great importance in considering the suitability of rocks or sediments as oil or gas reservoirs, or as aquifers. (
  • Examples of materials that porosity is of importance include catalysts, construction materials, ceramics, pharmaceutical products, metal powders, membranes, active components in batteries and fuel cells, and oil and gas bearing reservoirs. (
  • A nuclear magnetic resonance (NMR) based method was developed to accurately determine petrophysical properties including porosity, bulk density, and matrix density from drill cuttings of unconventional tight reservoirs. (
  • Porosity that is not considered "effective porosity" includes water bound to clay particles (known as bound water) and isolated "vuggy" porosity (vugs not connected to other pores). (
  • Whereas the stiffness of evolved optimized bone declines proportional to the square of its density, mechanical studies performed by Sandia researcher Thomas Buchheit working with UNM student Christopher Hartshorn showed that the stiffness/modulus of self-assembled materials was much less sensitive to increasing porosity: For a material synthesized with a cubic arrangement of pores, the modulus declined only as the square root of its density. (
  • Compressibility as a function of porosity for a glass containing spherically shaped pores. (
  • Initial dissolution of cement phases occurs in the 10-20 nm pores and leads to the development of new pore spaces that are eventually sealed by CaCO 3 precipitation, leading to a loss of gel and capillary nanopores, smoother pore surfaces, and reduced porosity. (
  • Catalyst porosity can be characterised by adsorption isotherms, usually with nitrogen. (
  • Porosity is of great industrial concern as it influences the behavior of gas adsorption and fluid flow within materials. (
  • Soil porosity affects drainage, allowing soils to hold water for plant consumption, and draining excess water. (
  • Poor porosity facilitates erosion of soils as rainwater washes particles off the surface rather than penetrating into soil. (
  • On the other end of the spectrum, sandy soils drain well and have fairly decent porosity, even though the spaces between the particles are small. (
  • The garden soils with the best porosity are loamy soils, which are mixtures of clay, silt and sand with organic matter. (
  • Laboratory and field-based studies of abundances, small-scale patchiness, and diversity of gymnamoebae in soils of varying porosity and organic con. (
  • The performance of multifunctional porous ceramics is often hindered by the seemingly contradictory effects of porosity on both mechanical and non-structural properties and yet a sufficient body of knowledge linking microstructure to these properties does not exist. (
  • Some of these petrophysical parameters, such as density and porosity, are important for determination of resources in place and rock typing. (
  • Optimization of process parameters is critical to minimize the porosity, as well as to maximize the strain at fracture performance of die cast components. (
  • introducing a grout slurry of water and spent oil shale containing less than 0.2% by weight carbon to said porous zone before retorting is completed to substantially minimize the porosity of said zone. (
  • Powder spray processes will give more scope in amount, size, shape and distribution of porosity. (
  • This porosity can range in size, from sub-micron to voids greater than 10 mm, depending on the casting. (
  • Usually the ragged edged cavities are associated with the last areas to solidify in contrast to the smooth rounded voids resulting from gas porosity. (
  • The general technique for eliminating shrinkage porosity is to ensure that liquid metal under pressure continues to flow into the voids as they form. (
  • Through porosity creates leak paths that enable gas and liquids to escape, while blind porosity can cause internal corrosion and defects if cleaning solutions leech out of the voids after surface finishing. (
  • Porosity is normally investigated by ultrasound techniques that, on the other hand, under usual conditions, are not always able to distinguish voids from resin starved zones (which they are themselves defects under some circumstances). (
  • Vacuum impregnation is an effective way to seal porosity in castings, but companies need to choose whether to perform this operation before or after machining the casting. (
  • IMPCO's AlumiSeal is a brush-on methacrylate compound formulated to seal porosity in aluminum parts and welds that will contain liquids or gases under pressure. (
  • Vacuum impregnation is a preferred OEM process that seals porosity and leak paths in metal castings, sintered metal parts and electrical castings that form during the casting or molding process. (
  • Vacuum impregnation seals porosity and leak paths for the following reasons. (
  • A weld area on an aluminum weldment is exposed to sulfur hexafluoride to chemically bind hydrogen in the weld area with the sulfur hexafluoride to reduce porosity. (
  • introducing grout slurry by fluid communication to the zone so as to deposit slurry and reduce porosity. (
  • In this paper the linear theory of viscoelasticity for Kelvin-Voigt materials with double porosity is presented and the basic partial differential equations are derived. (
  • The system of these equations is based on the equations of motion, conservation of fluid mass, the effective stress concept and Darcy's law for materials with double porosity. (
  • This theory is a straightforward generalization of the earlier proposed dynamical theory of elasticity for materials with double porosity. (
  • The results obtained from this study can be summarized as follows: through a Kelvin-Voigt material with double porosity three longitudinal and two transverse plane harmonic attenuated waves propagate. (
  • J. G. Berryman and H. F. Wang, The elastic coefficients of double-porosity models for fluid transport in jointed rock,, Journal of Geophysical Research , 100 (1995), 24611. (
  • J. G. Berryman and H. F. Wang, Elastic wave propagation and attenuation in a double-porosity dual-permiability medium,, International Journal of Rock Mechanics and Mining Sciences , 37 (2000), 63. (
  • D. E. Beskos and E. C. Aifantis, On the theory of consolidation with double porosity - II,, International Journal of Engineering Science , 24 (1986), 1697. (
  • M. Ciarletta, F. Passarella and M. Svanadze, Plane waves and uniqueness theorems in the coupled linear theory of elasticity for solids with double porosity,, Journal of Elasticity , 114 (2014), 55. (
  • It will help you better determine your hair's porosity. (
  • The key to working with your hair's porosity is how you layer your products on wet, clean hair. (
  • The most effective were the membranes of the lowest content of polyvinylpyrrolidone, while the lowest values of resistance showed the membranes of the highest content of PVP, and so the ones of the greatest porosity. (
  • The greatest porosity and permeability development occur at the toe and at the top of the mixing zone. (
  • In die casting processes, the mould filling phase is highly critical because defects such as air entrapment and shrinkage porosity might occur. (
  • To predict shrinkage porosity and other defects, simulation has been increasingly used nowadays, as these software require less development cost and time than experiments. (
  • If the shrinkage porosity is small in diameter and limited to the very centre of thick sections it won't cause massive problems. (
  • Using die casting simulation programs for shrinkage porosity prediction can lead to significant costs reduction thanks to major improvements in material and energy consumption, labour resources, and scraps reduction. (
  • Typically a B-scan display is used to detect and characterise porosity. (
  • This result proves our early prediction about mechanism of light-induced fat cells' lipolysis via increased cell membrane porosity. (
  • Consequently, we consider the in situ hardening system being an excellent candidate as a filling material for non-weight-bearing orthopedic indications, as the resulting properties of the hardened implant fulfill indication-specific needs like mechanical stability, elasticity, and porosity. (
  • WeldSeal from IMPCO Inc. (East Providence, RI) is a brush-on methacrylate compound formulated for sealing porosity in welds that will contain gases under pressure, or liquids. (
  • In metal castings, porosity is typically considered any void found in the casting. (
  • In the course of sealing castings against porosity, the parts would be processed through the following four stations: Impregnation Chamber: The operator would seal the chamber and draw a vacuum. (
  • A major problem in castings, porosity is principally caused by the shrinkage that accompanies solidification. (
  • Porosity can affect the structural integrity and functionality of castings, but performing vacuum impregnation at the right point in the part production process can prevent these issues. (
  • Porosity in castings comes in three types: blind (highlighted in blue), through (highlighted in red) and fully enclosed (highlighted in green). (
  • Porosity is a naturally occurring phenomenon that is found in most materials, but it can affect the structural integrity and functionality of metal castings. (
  • Understanding the types of porosity that occur in castings can help companies decide when to vacuum impregnate castings. (
  • In metal castings, porosity is considered to be any void in the casting. (
  • and Fairchild, S., "Improvement of Strain at Fracture and Porosity Levels in Magnesium Die Castings Using the Taguchi Design of Experiments and Analysis," SAE Technical Paper 970327, 1997, . (
  • Densities, and the porosities that can be derived from them, are very important parameters in understanding water flow through the surface of the Earth. (
  • hi all we are using 9mb gun we are trying to coat pac127(72F NS) we are getting the porosity around 26% we are yousing the recommended parameter by powder alloy corporation and the metco parameters also but we are not getting the dense coating. (
  • Models to predict permeability from porosity and other measurable rock parameters fall into three classes based on either grain, surface area, or pore dimension considerations. (
  • 1] In shallow unconfined aquifers, the response of the water table (WT) to input and output water fluxes is controlled by two distinct storage parameters, drainable and fillable porosity, which are applicable for WT drawdown and rise, respectively. (
  • From result analysis, metal temperature and intermediate shot velocity are the most influential parameters for porosity, whereas cavity fill time is the most influential parameter for strain at fracture. (
  • Porosity influences the physical exchanges and chemical reactivity of solids with gases and liquids. (
  • 4. The dual porosity tube of claim 1, wherein the dual porosity tube has a microstructure having internodal distances at inner and outer surfaces of the dual porosity PTFE tube within a range of about 0.10-200 μ. (
  • The results have shown that the modification of polymer membranes by the use of different amounts of the pore forming agent in their syntheses leads to significant changes in porosity and has beneficial effect on equilibrium water content. (
  • 2012) describe the importance of the pore size for the porosity of barrier membranes. (
  • Relevant storage capacity is considered to have evolved with thermal decomposition of organic matter during catagenesis, where we estimate that kerogen porosity does not typically exceed 3% of bulk rock volume. (
  • The spaces between minerals and organic materials in the soil indicate porosity. (
  • Organic matter improves drainage and porosity in all three soil types. (
  • The system that I present is part of my current pipeline with ZBrush, streamlines the porosity detailing process and accentuates the organic aspect of the skin, being also adaptable to "non-human" skins. (
  • Log derivation of effective porosity includes CBW as part of the volume of shale (Vsh). (
  • To address this newly recognized and important nonmatrix kerogen pore system, that is arguably the dominant hydrocarbon storage and mobility network in these rocks, we introduce a relatively simple kinetic model that describes porosity development within kerogen as a function of thermal maturation.Kerogen porosity development is estimated within the upper Albian Mowry Shale in the Powder River Basin of Wyoming to illustrate the approach. (
  • This invention relates to a method for reducing the porosity of rubblized oil shale and the recovery of carbonaceous materials from underground deposits. (
  • NMR technology allows for the separation of liquid signals from within and between the shale cutting particles and when used in combination with Archimedes-based mass measurements provides accurate porosity and density data for both vertical and horizontal wells. (
  • Intertek measures catalyst surface area, porosity and other important catalyst measurement factors. (
  • data trends cut the curves of constant pore size from the pore-dimension models, which shows that porosity reduction is always accompanied by a reduction in characteristic pore size. (
  • The high powers of porosity of the grain-based and surface-area models are required to compensate for the inclusion of the small end of the pore size spectrum. (
  • Hello, Have you ever heard about using so-called porosity function to describe boundary conditions in case when the physical boundary is not linear with the edges of the computational cells? (
  • The term porosity is generally used to describe cavities produced within a solidified casting, due to specific volume contraction on solidification. (
  • We have constructed detailed contour maps that describe local porosity distributions and the mineralogy of the sample and relate these quantities to the carbon dioxide reaction front on the cement. (
  • This paper will describe the high porosity DPF material development, including test results and future outlook. (
  • Owing to porosity, the surface area inside a coal particle is far higher than the external surface area. (
  • We provide world-class expertise in both catalyst surface area analysis and catalyst porosity testing. (
  • The TriStar II Plus is a an automated, three-station, surface area and porosity analyzer that delivers excellent performance and speed of analysis. (
  • Zirconium oxide has caused no pronounced effect on the development of surface area while barium hydroxide showed adverse effect and caused a decline in porosity. (
  • One embodiment of the prevent invention provides a method of creating a high porosity propped fracture comprising creating a slurry comprising a treatment fluid, proppant particulates, pieces of reticulated foam having cells, and an adhesive substance such that the adhesive substance at least partially. (
  • and, depositing at least a portion of the reticulated foam fragments having proppant particulates embedded therein in one or more fractures within a portion of a subterranean formation so as to form a high porosity propped fracture. (
  • Finally, unlike strain at fracture models which are not reproducible, the porosity models are reproducible for both stages of the experiments. (
  • Monolithic Glass Scaffolds with Dual Porosity Prepared by Polymer. (
  • Porous hydroxyapatite (HA) scaffolds with porosity-graded structures were fabricated by sequential freeze-casting. (
  • The porosities of the inner and outer layers of the graded HA scaffolds were controlled by adjusting the initial HA contents of the casting slurries. (
  • Jung, H.-D. The Production of Porous Hydroxyapatite Scaffolds with Graded Porosity by Sequential Freeze-Casting. (
  • The Classification of Carbonate Porosity. (
  • The Nature and Classification of Carbonate Porosity. (
  • The Lucia rock fabric/petrophysical carbonate porosity classification. (
  • Given the comparatively long span of geologic time, this process may be largely responsible for porosity and permeability development observed in those carbonate rocks through which a freshwater-saltwater mixing zone had at one time migrated. (
  • There are several mechanisms that induce porosities to occur. (
  • Vacuum impregnation prevents fluids or gases from leaking by sealing the porosity and leak paths. (
  • Porosity in welding is a result of dissolved gases or gases released during the welding process, being trapped in the metal when there is insufficient time to escape prior to solidification. (
  • Porosity sealing is done through the process of vacuum impregnation. (
  • Vacuum impregnation stops casting porosity (a phenomenon that occurs in the die-cast manufacturing process and allows manufacturers to use parts that would otherwise be scrapped. (
  • Manufacturers can also increase the amount of material removed during cubing to maximize porosity exposure and perform vacuum impregnation after. (
  • Because of the presence of the large amount of uncured hydroxyl groups and the high porosity, the films absorb moisture resulting in property variation as a function of moisture level and eventual deterioration, and allow electrical and gas leakage and optical loss. (
  • It is an object of this invention to provide sol-gel preparation of uniformly and highly dense low porosity titania forms containing only a small amount of hydroxyl groups and possessing a high refractive index, which do not absorb moisture and thus are property stable regardless of humidity level and resistant to humidity induced deterioration and which prohibit electrical and gas leakage and optical loss. (
  • The moisture content, permeability rate, and porosity of local soil samples may be tested and compared to that of sand, which is included in the kit. (
  • Porosity is determined by how your hair receives moisture. (
  • Very porous hair can absorb more than twice the amount of water and moisture than hair with normal or low porosity can. (
  • Hair is slower to absorb water and longer to release it, so low porosity hair holds moisture quite well. (
  • However, only the drainable porosity estimated from the hydrostatic soil moisture profile is in common use. (
  • Separate analytical expressions are developed for drainable and fillable porosity accounting for dynamic soil moisture conditions through the assumption of successive steady state fluxes in the unsaturated zone. (
  • The Exploring Porosity and Permeability Lab Activity make observing and calculating drainage rates and pore spacing simple. (
  • The great amount of EcoPeat enhances drainage and porosity. (
  • To increase porosity, a pore forming agent (NaCMC) was added and to enhance mechanical properties of the system, an inorganic filler (α-TCP) was incorporated. (
  • Porosity is a key factor in bone bio material design - it should be large enough as to allow for vascularization, but if it becomes too large, important mechanical properties such as stiffness and strength get too much compromised.Hence, porosity-mechanical properties are of key interest, and such relationships have been investigated experimentally,relating the data from mass or imaging tests to data from mechanical and acoustical tests. (
  • The virtual fragmented fractal porous medium so generated is exposed to various uniaxial stresses to simulate gob compaction and porosity and permeability changes during this process. (
  • It was shown that the porosity level depends on the compaction pressures, sintering temperatures and holding times. (
  • Knowing the hair type and porosity of your hair can lead to a better understanding of what products to use, what styles to try, and overall care techniques for your best head of curls. (
  • Despite its importance, the gob is typically inaccessible for performing direct measurements of porosity and permeability. (
  • Off the shelf commercial products like Metco 601 and Diamalloy 4001 and other brands would initially be worth trying (typically around 50% volume polyester retained in coating), but you may find blending your own will give more versatility in fine tuning your coating to give the porosity you need. (
  • However, since neutron logs sense H (hydrogen) and all hydrogen so-sensed is allocated as pore space, then neutron logs will overestimate porosity in argillaceous rocks by sensing OH− as part of the pore space. (
  • The results suggest that the gob porosity and permeability values can be predicted by this approach and the presented models are capable to produce values close to values documented by other researchers. (
  • In this work, results of the porosity control in the Ti-13Nb-13Zr alloy produced by powder metallurgy are presented. (
  • The porosity predictions are in good agreement with the experimental results in the as-cast NGVs. (
  • If the porosity and permeability are not known, experimental results are necessary to quantify these material properties. (
  • Corresponding experimental results show that porosity was absent in the melt runs made at higher power and higher welding speed. (
  • Based on the combination of experimental results and numerical predictions, it is proposed that porosity formation when keyhole laser welding may result from turbulent fluid flow behind the keyhole, with the larger the value of associated Reynolds number, the higher the possibility of porosity formation. (
  • Precision, like most manufacturers, knows that all Ram Air parachutes built with conventional low porosity fabric are adversely affected by handling of the fabric. (
  • In spite of its relatively poor reflecting characteristics, porosity detection is not as challenging a task for ultrasonic testing as one might think. (
  • This article gives you other characteristics of high, normal, and low porosity hair. (
  • Among them, polymers of intrinsic micro-porosity (PIMs) have been regarded as a potential next-generation membrane material for their ultra-permeable characteristics and their solution-processing ability. (
  • This has been used to analyze possible porosity formation mechanisms, based on predictions of keyhole behavior and fluid flow characteristics in the weld pool. (
  • The approach allows the calculation of porosity and permeability from the size distribution of broken rock material in the gob, which can be determined from image analyzes of gob material using the theories on a completely fragmented porous medium. (
  • By solving the Navier-Stokes equations (or its linear approximation for small Reynolds numbers, called Stokes flow or creeping flow) on the microscale geometry, the porosity and permeability of the porous medium can be extracted. (
  • Before we investigate the porosity and permeability of a porous medium, we must discuss the generation of the microscale geometry. (
  • is attributable to their high porosity and permeability. (
  • Do i have High porosity or Low porosity? (
  • High porosity values indicate high capacities of the reservoir rocks to contain these fluids, while low porosity values indicate the opposite. (
  • In checking some reserves in their systems, they found porosity readings as high as 18 cfm in some areas of a parachute after only 30 repacks had been performed. (
  • High Porosity DPF Design for Integrated SCR Functions," SAE Technical Paper 2012-01-0843, 2012, . (
  • Therefore, a high porosity DPF design has been developed to overcome the trade off between high pressure drop, high wash coat loadings, and sufficient filtration efficiency. (
  • Lambert EPM-40 High Porosity Mix is a blend of coarse Canadian sphagnum peat moss and EcoPeat. (
  • Porosity is the volume percentage of "void" (actually fluid- or air-filled) space in a rock, whereas permeability is defined as the rate of flow of water at a given pressure gradient through a unit volume. (
  • For such fluid flow controlled porosities, measures to decrease Reynolds number of the fluid flow close to the keyhole could prove effective in reducing or avoiding porosity. (
  • Porosity occurs naturally and is found in most materials. (
  • For each of these structures, increasing porosity caused a reduction in modulus, but the reduction was less than for theoretically optimized or naturally evolved materials due to the attendant stiffening of the thinning nanoscale silica walls resulting from the formation of small stiff silica rings. (
  • When it comes to porosity and its effects on curly hair styling, naturally curly consumers are well ahead of the curve. (
  • However, microporous pore space associated with shales (where water is held by capillary forces and hence is not true CBW) is usually estimated as part of the Vsh by logs and therefore not included as part of the effective porosity. (