Adsorption: The adhesion of gases, liquids, or dissolved solids onto a surface. It includes adsorptive phenomena of bacteria and viruses onto surfaces as well. ABSORPTION into the substance may follow but not necessarily.Surface Properties: Characteristics or attributes of the outer boundaries of objects, including molecules.Bentonite: A colloidal, hydrated aluminum silicate that swells 12 times its dry size when added to water.Silicon Dioxide: 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.Surface Tension: The force acting on the surface of a liquid, tending to minimize the area of the surface. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Aluminum Silicates: Any of the numerous types of clay which contain varying proportions of Al2O3 and SiO2. They are made synthetically by heating aluminum fluoride at 1000-2000 degrees C with silica and water vapor. (From Hawley's Condensed Chemical Dictionary, 11th ed)Polystyrenes: Polymerized forms of styrene used as a biocompatible material, especially in dentistry. They are thermoplastic and are used as insulators, for injection molding and casting, as sheets, plates, rods, rigid forms and beads.Charcoal: An amorphous form of carbon prepared from the incomplete combustion of animal or vegetable matter, e.g., wood. The activated form of charcoal is used in the treatment of poisoning. (Grant & Hackh's Chemical Dictionary, 5th ed)Surface-Active Agents: Agents that modify interfacial tension of water; usually substances that have one lipophilic and one hydrophilic group in the molecule; includes soaps, detergents, emulsifiers, dispersing and wetting agents, and several groups of antiseptics.Hydroxyapatites: A group of compounds with the general formula M10(PO4)6(OH)2, where M is barium, strontium, or calcium. The compounds are the principal mineral in phosphorite deposits, biological tissue, human bones, and teeth. They are also used as an anticaking agent and polymer catalysts. (Grant & Hackh's Chemical Dictionary, 5th ed)Glass: 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.Membranes, Artificial: Artificially produced membranes, such as semipermeable membranes used in artificial kidney dialysis (RENAL DIALYSIS), monomolecular and bimolecular membranes used as models to simulate biological CELL MEMBRANES. These membranes are also used in the process of GUIDED TISSUE REGENERATION.Bacteriophages: Viruses whose hosts are bacterial cells.Biofouling: Process by which unwanted microbial, plant or animal materials or organisms accumulate on man-made surfaces.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Air: The mixture of gases present in the earth's atmosphere consisting of oxygen, nitrogen, carbon dioxide, and small amounts of other gases.Water: 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)Solutions: The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)Serum Albumin, Bovine: Serum albumin from cows, commonly used in in vitro biological studies. (From Stedman, 25th ed)Hydrophobic and Hydrophilic Interactions: The thermodynamic interaction between a substance and WATER.Kinetics: The rate dynamics in chemical or physical systems.Porosity: 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.Colloids: Two-phase systems in which one is uniformly dispersed in another as particles small enough so they cannot be filtered or will not settle out. The dispersing or continuous phase or medium envelops the particles of the discontinuous phase. All three states of matter can form colloids among each other.Polymers: Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).Water Purification: Any of several processes in which undesirable impurities in water are removed or neutralized; for example, chlorination, filtration, primary treatment, ion exchange, and distillation. It includes treatment of WASTE WATER to provide potable and hygienic water in a controlled or closed environment as well as provision of public drinking water supplies.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Zeolites: Zeolites. A group of crystalline, hydrated alkali-aluminum silicates. They occur naturally in sedimentary and volcanic rocks, altered basalts, ores, and clay deposits. Some 40 known zeolite minerals and a great number of synthetic zeolites are available commercially. (From Merck Index, 11th ed)Gold: A yellow metallic element with the atomic symbol Au, atomic number 79, and atomic weight 197. It is used in jewelry, goldplating of other metals, as currency, and in dental restoration. Many of its clinical applications, such as ANTIRHEUMATIC AGENTS, are in the form of its salts.Thermodynamics: A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)Kaolin: The most common mineral of a group of hydrated aluminum silicates, approximately H2Al2Si2O8-H2O. It is prepared for pharmaceutical and medicinal purposes by levigating with water to remove sand, etc. (From Merck Index, 11th ed) The name is derived from Kao-ling (Chinese: "high ridge"), the original site. (From Grant & Hackh's Chemical Dictionary, 5th ed)Coated Materials, Biocompatible: Biocompatible materials usually used in dental and bone implants that enhance biologic fixation, thereby increasing the bond strength between the coated material and bone, and minimize possible biological effects that may result from the implant itself.Cellulose: A polysaccharide with glucose units linked as in CELLOBIOSE. It is the chief constituent of plant fibers, cotton being the purest natural form of the substance. As a raw material, it forms the basis for many derivatives used in chromatography, ion exchange materials, explosives manufacturing, and pharmaceutical preparations.Models, Chemical: Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.Microscopy, Atomic Force: A type of scanning probe microscopy in which a probe systematically rides across the surface of a sample being scanned in a raster pattern. The vertical position is recorded as a spring attached to the probe rises and falls in response to peaks and valleys on the surface. These deflections produce a topographic map of the sample.Quartz Crystal Microbalance Techniques: The use of a quartz crystal microbalance for measuring weights and forces in the micro- to nanogram range. It is used to study the chemical and mechanical properties of thin layers, such as polymer coatings and lipid membranes; and interactions between molecues.Silica Gel: A non-crystalline form of silicon oxide that has absorptive properties. It is commonly used as a desiccating agent and as a stationary phase for CHROMATOGRAPHY. The fully hydrated form of silica gel has distinct properties and is referred to as SILICIC ACID.Chitosan: Deacetylated CHITIN, a linear polysaccharide of deacetylated beta-1,4-D-glucosamine. It is used in HYDROGEL and to treat WOUNDS.Cetrimonium Compounds: Cetyltrimethylammonium compounds that have cationic detergent, antiseptic, and disinfectant activities. They are used in pharmaceuticals, foods, and cosmetics as preservatives; on skin, mucous membranes, etc., as antiseptics or cleansers, and also as emulsifiers. These compounds are toxic when used orally due to neuromuscular blockade.Photoelectron Spectroscopy: The study of the energy of electrons ejected from matter by the photoelectric effect, i.e., as a direct result of absorption of energy from electromagnetic radiation. As the energies of the electrons are characteristic of a specific element, the measurement of the energy of these electrons is a technique used to determine the chemical composition of surfaces.Enzymes, Immobilized: Enzymes which are immobilized on or in a variety of water-soluble or water-insoluble matrices with little or no loss of their catalytic activity. Since they can be reused continuously, immobilized enzymes have found wide application in the industrial, medical and research fields.Durapatite: The mineral component of bones and teeth; it has been used therapeutically as a prosthetic aid and in the prevention and treatment of osteoporosis.Quartz: Quartz (SiO2). A glassy or crystalline form of silicon dioxide. Many colored varieties are semiprecious stones. (From Grant & Hackh's Chemical Dictionary, 5th ed)Receptors, Virus: Specific molecular components of the cell capable of recognizing and interacting with a virus, and which, after binding it, are capable of generating some signal that initiates the chain of events leading to the biological response.Actinomyces: A genus of gram-positive, rod-shaped bacteria whose organisms are nonmotile. Filaments that may be present in certain species are either straight or wavy and may have swollen or clubbed heads.Pulmonary Surfactants: Substances and drugs that lower the SURFACE TENSION of the mucoid layer lining the PULMONARY ALVEOLI.Polyethylene Glycols: Polymers of ETHYLENE OXIDE and water, and their ethers. They vary in consistency from liquid to solid depending on the molecular weight indicated by a number following the name. They are used as SURFACTANTS, dispersing agents, solvents, ointment and suppository bases, vehicles, and tablet excipients. Some specific groups are NONOXYNOLS, OCTOXYNOLS, and POLOXAMERS.Aluminum Hydroxide: A compound with many biomedical applications: as a gastric antacid, an antiperspirant, in dentifrices, as an emulsifier, as an adjuvant in bacterins and vaccines, in water purification, etc.Electrochemistry: The study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.Micropore Filters: A membrane or barrier with micrometer sized pores used for separation purification processes.Static Electricity: The accumulation of an electric charge on a objectTetraphenylborate: An anionic compound that is used as a reagent for determination of potassium, ammonium, rubidium, and cesium ions. It also uncouples oxidative phosphorylation and forms complexes with biological materials, and is used in biological assays.Silanes: Compounds similar to hydrocarbons in which a tetravalent silicon atom replaces the carbon atom. They are very reactive, ignite in air, and form useful derivatives.Graphite: An allotropic form of carbon that is used in pencils, as a lubricant, and in matches and explosives. It is obtained by mining and its dust can cause lung irritation.Biocompatible Materials: Synthetic or natural materials, other than DRUGS, that are used to replace or repair any body TISSUES or bodily function.Viral Plaque Assay: Method for measuring viral infectivity and multiplication in CULTURED CELLS. Clear lysed areas or plaques develop as the VIRAL PARTICLES are released from the infected cells during incubation. With some VIRUSES, the cells are killed by a cytopathic effect; with others, the infected cells are not killed but can be detected by their hemadsorptive ability. Sometimes the plaque cells contain VIRAL ANTIGENS which can be measured by IMMUNOFLUORESCENCE.Muramidase: A basic enzyme that is present in saliva, tears, egg white, and many animal fluids. It functions as an antibacterial agent. The enzyme catalyzes the hydrolysis of 1,4-beta-linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in peptidoglycan and between N-acetyl-D-glucosamine residues in chitodextrin. EC 3.2.1.17.Acrylic ResinsSpectroscopy, Fourier Transform Infrared: A spectroscopic technique in which a range of wavelengths is presented simultaneously with an interferometer and the spectrum is mathematically derived from the pattern thus obtained.Lipid Bilayers: Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.Buffers: A chemical system that functions to control the levels of specific ions in solution. When the level of hydrogen ion in solution is controlled the system is called a pH buffer.Water Pollutants, Chemical: Chemical compounds which pollute the water of rivers, streams, lakes, the sea, reservoirs, or other bodies of water.Sewage: Refuse liquid or waste matter carried off by sewers.Resins, Synthetic: Polymers of high molecular weight which at some stage are capable of being molded and then harden to form useful components.Hemofiltration: Extracorporeal ULTRAFILTRATION technique without HEMODIALYSIS for treatment of fluid overload and electrolyte disturbances affecting renal, cardiac, or pulmonary function.Ions: An atom or group of atoms that have a positive or negative electric charge due to a gain (negative charge) or loss (positive charge) of one or more electrons. Atoms with a positive charge are known as CATIONS; those with a negative charge are ANIONS.Phosphatidylcholines: Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to a choline moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and choline and 2 moles of fatty acids.Diatomaceous Earth: A form of SILICON DIOXIDE composed of skeletons of prehistoric aquatic plants which is used for its ABSORPTION quality, taking up 1.5-4 times its weight in water. The microscopic sharp edges are useful for insect control but can also be an inhalation hazard. It has been used in baked goods and animal feed. Kieselguhr is German for flint + earthy sediment.

Characterization of human bactericidal antibodies to Bordetella pertussis. (1/3424)

The Bordetella pertussis BrkA protein protects against the bactericidal activity of complement and antibody; however, some individuals mount an immune response that overcomes this bacterial defense. To further characterize this process, the bactericidal activities of sera from 13 adults with different modes of exposure to B. pertussis (infected as adults, occupational exposure, immunized with an acellular vaccine, or no identified exposure) against a wild-type strain and a BrkA complement-sensitive mutant were evaluated. All of the sera killed the BrkA mutant, suggesting past exposure to B. pertussis or cross-reactive organisms. Several samples had no or minimal activity against the wild type. All of the sera collected from the infected and occupationally exposed individuals but not all of the sera from vaccinated individuals had bactericidal activity against the wild-type strain, suggesting that some types of exposure can induce an immune response that can overcome the BrkA resistance mechanism. Adsorbing serum with the wild-type strain removed the bactericidal antibodies; however, adsorbing the serum with a lipopolysaccharide (LPS) mutant or an avirulent (bvg mutant) strain did not always result in loss of bactericidal activity, suggesting that antibodies to either LPS or bvg-regulated proteins could be bactericidal. All the samples, including those that lacked bactericidal activity, contained antibodies that recognized the LPS of B. pertussis. Bactericidal activity correlated best with the presence of the immunoglobulin G3 (IgG3) antibodies to LPS, the IgG subtype that is most effective at fixing complement.  (+info)

Surface-induced polymerization of actin. (2/3424)

Living cells contain a very large amount of membrane surface area, which potentially influences the direction, the kinetics, and the localization of biochemical reactions. This paper quantitatively evaluates the possibility that a lipid monolayer can adsorb actin from a nonpolymerizing solution, induce its polymerization, and form a 2D network of individual actin filaments, in conditions that forbid bulk polymerization. G- and F-actin solutions were studied beneath saturated Langmuir monolayers containing phosphatidylcholine (PC, neutral) and stearylamine (SA, a positively charged surfactant) at PC:SA = 3:1 molar ratio. Ellipsometry, tensiometry, shear elastic measurements, electron microscopy, and dark-field light microscopy were used to characterize the adsorption kinetics and the interfacial polymerization of actin. In all cases studied, actin follows a monoexponential reaction-limited adsorption with similar time constants (approximately 10(3) s). At a longer time scale the shear elasticity of the monomeric actin adsorbate increases only in the presence of lipids, to a 2D shear elastic modulus of mu approximately 30 mN/m, indicating the formation of a structure coupled to the monolayer. Electron microscopy shows the formation of a 2D network of actin filaments at the PC:SA surface, and several arguments strongly suggest that this network is indeed causing the observed elasticity. Adsorption of F-actin to PC:SA leads more quickly to a slightly more rigid interface with a modulus of mu approximately 50 mN/m.  (+info)

Bacteriophage inactivation at the air-water-solid interface in dynamic batch systems. (3/3424)

Bacteriophages have been widely used as surrogates for human enteric viruses in many studies on virus transport and fate. In this investigation, the fates of three bacteriophages, MS2, R17, and phiX174, were studied in a series of dynamic batch experiments. Both MS2 and R17 readily underwent inactivation in batch experiments where solutions of each phage were percolated through tubes packed with varying ratios of glass and Teflon beads. MS2 and R17 inactivation was the result of exposure to destructive forces at the dynamic air-water-solid interface. phiX174, however, did not undergo inactivation in similar studies, suggesting that this phage does not accumulate at air-water interfaces or is not affected by interfacial forces in the same manner. Other batch experiments showed that MS2 and R17 were increasingly inactivated during mixing in polypropylene tubes as the ionic strength of the solution was raised (phiX174 was not affected). By the addition of Tween 80 to suspensions of MS2 and R17, phage inactivation was prevented. Our data suggest that viral inactivation in simple dynamic batch experiments is dependent upon (i) the presence of a dynamic air-water-solid interface (where the solid is a hydrophobic surface), (ii) the ionic strength of the solution, (iii) the concentration of surface active compounds in the solution, and (iv) the type of virus used.  (+info)

Evidence that the neck appendages are adsorption organelles in Bacillus subtilis bacteriophage phi29. (4/3424)

A mutant of Bacillus subtilis unable to adsorb phage phi29 efficiently has been isolated. This mutant can be infected by host range mutants of the phage. Since the host range mutations map in cistron 12, which codes for neck appendage protein, this would tend to confirm that these organelles are involved in viral adsorption.  (+info)

Modulation of cell proliferation and differentiation through substrate-dependent changes in fibronectin conformation. (5/3424)

Integrin-mediated cell adhesion to extracellular matrices provides signals essential for cell cycle progression and differentiation. We demonstrate that substrate-dependent changes in the conformation of adsorbed fibronectin (Fn) modulated integrin binding and controlled switching between proliferation and differentiation. Adsorption of Fn onto bacterial polystyrene (B), tissue culture polystyrene (T), and collagen (C) resulted in differences in Fn conformation as indicated by antibody binding. Using a biochemical method to quantify bound integrins in cultured cells, we found that differences in Fn conformation altered the quantity of bound alpha5 and beta1 integrin subunits but not alphav or beta3. C2C12 myoblasts grown on these Fn-coated substrates proliferated to different levels (B > T > C). Immunostaining for muscle-specific myosin revealed minimal differentiation on B, significant levels on T, and extensive differentiation on C. Differentiation required binding to the RGD cell binding site in Fn and was blocked by antibodies specific for this site. Switching between proliferation and differentiation was controlled by the levels of alpha5beta1 integrin bound to Fn, and differentiation was inhibited by anti-alpha5, but not anti-alphav, antibodies, suggesting distinct integrin-mediated signaling pathways. Control of cell proliferation and differentiation through conformational changes in extracellular matrix proteins represents a versatile mechanism to elicit specific cellular responses for biological and biotechnological applications.  (+info)

Amino acid substitutions in a conserved region in the stalk of the Newcastle disease virus HN glycoprotein spike impair its neuraminidase activity in the globular domain. (6/3424)

The ectodomain of the paramyxovirus haemagglutinin-neuraminidase (HN) glycoprotein spike can be divided into two regions: a membrane-proximal, stalk-like structure and a terminal globular domain. The latter contains all the antibody recognition sites of the protein, as well as its receptor recognition and neuraminidase (NA) active sites. These two activities of the protein can be separated by monoclonal antibody functional inhibition studies and mutations in the globular domain. Herein, we show that mutation of several conserved residues in the stalk of the Newcastle disease virus HN protein markedly decrease its NA activity without a significant effect on receptor recognition. Thus, mutations in the stalk, distant from the NA active site in the globular domain, can also separate attachment and NA. These results add to an increasing body of evidence that the NA activity of this protein is dependent on an intact stalk structure.  (+info)

Differential mechanisms of retinoid transfer from cellular retinol binding proteins types I and II to phospholipid membranes. (7/3424)

Cellular retinol-binding proteins types I and II (CRBP-I and CRBP-II) are known to differentially facilitate retinoid metabolism by several membrane-associated enzymes. The mechanism of ligand transfer to phospholipid small unilamellar vesicles was compared in order to determine whether differences in ligand trafficking properties could underlie these functional differences. Unidirectional transfer of retinol from the CRBPs to membranes was monitored by following the increase in intrinsic protein fluorescence that occurs upon ligand dissociation. The results showed that ligand transfer of retinol from CRBP-I was >5-fold faster than transfer from CRBP-II. For both proteins, transfer of the other naturally occurring retinoid, retinaldehyde, was 4-5-fold faster than transfer of retinol. Rates of ligand transfer from CRBP-I to small unilamellar vesicles increased with increasing concentration of acceptor membrane and with the incorporation of the anionic lipids cardiolipin or phosphatidylserine into membranes. In contrast, transfer from CRBP-II was unaffected by either membrane concentration or composition. Preincubation of anionic vesicles with CRBP-I was able to prevent cytochrome c, a peripheral membrane protein, from binding, whereas CRBP-II was ineffective. In addition, monolayer exclusion experiments demonstrated differences in the rate and magnitude of the CRBP interactions with phospholipid membranes. These results suggest that the mechanisms of ligand transfer from CRBP-I and CRBP-II to membranes are markedly different as follows: transfer from CRBP-I may involve and require effective collisional interactions with membranes, whereas a diffusional process primarily mediates transfer from CRBP-II. These differences may help account for their distinct functional roles in the modulation of intracellular retinoid metabolism.  (+info)

Lysozyme sorption in hydrogel contact lenses. (8/3424)

PURPOSE: To examine the processes involved in formation of protein deposits on hydrogel contact lenses. METHODS: The adsorption and/or penetration of lysozyme on or into three types of contact lenses, etafilcon A, vifilcon A, and tefilcon, were investigated in vitro using a radiolabel-tracer technique, x-ray photoelectron spectroscopy, and laser scanning confocal microscopy. RESULTS: Binding of lysozyme to high-water-content, ionic contact lenses (etafilcon A and vifilcon A) was dominated by a penetration process. The extent of this penetration was a function of charge density of the lenses, so that there was a higher degree of penetration of lysozyme in etafilcon A than in vifilcon A lenses. In contrast, the binding of lysozyme to tefilcon lenses was a surface adsorption process. The adsorption and desorption kinetics showed similar trends to those found in human serum albumin (HSA) adsorption on lens surfaces. However, the extent of lysozyme adsorption on tefilcon is much higher than HSA adsorption, probably because of the self-association of lysozyme on the tefilcon lens surface. Furthermore, either penetration or adsorption of lysozyme involved reversible and irreversible processes and were both time dependent. CONCLUSIONS: Binding of lysozyme to hydrogel lenses involves surface adsorption or matrix penetration. These processes may be reversible or irreversible. The properties of the lens materials, such as charge density (ionicity) and porosity (water content) of the lenses, determine the type and rates of these processes.  (+info)

This paper presents the adsorption properties of the o-Al13Co4(100) surface toward molecules involved in the semihydrogenation of acetylene. The energetically favored adsorption sites of H, C2H2, C2H3, and C2H4 are determined thanks to ab initio density functional calculations. The surface model used for this study has been determined previously [Phys. Rev. B 2011, 84, 085411], using an approach combining both experimental observations and density functional theory calculations. We show that although the surface termination layer of o-Al13Co4(100) is a dense Al-rich layer, its adsorption properties are quite different from pure elemental Al surfaces, especially for atomic hydrogen adsorption (exothermic on o-Al13Co4(100) and endothermic on low index Al surfaces). The role of surface and subsurface cobalt atoms is investigated carefully. The electronic donor/acceptor character of subsurface cobalt atoms is shown to influence the adsorption properties. In particular, the subsurface cobalt atoms have a
TY - JOUR. T1 - Protein Adsorption on Grafted Zwitterionic Polymers Depends on Chain Density and Molecular Weight. AU - Ahmed, Syeda Tajin. AU - Leckband, Deborah E.. PY - 2020/7/1. Y1 - 2020/7/1. N2 - This study demonstrates that protein adsorption on end-grafted, zwitterionic poly(sulfobetaine) (pSBMA) thin films depends on the grafting density, molecular weight, and ionic strength. Zwitterionic polymers exhibit ultralow nonspecific fouling (protein adsorption) and excellent biocompatibility. This picture contrasts with a recent report that soluble pSBMA chains bind proteins and alter the protein folding stability. To address this apparent contradiction, the dependence of protein adsorption on the chain grafting parameters is investigated: namely, the grafting density, molecular weight, and ionic strength. Studies compared the adsorption of phosphoglycerate kinase and positively charged lysozyme versus the scaled grafting parameter s/2RF, where s is the distance between grafting sites and RF ...
TY - JOUR. T1 - Adsorption properties and behavior of the platinum group metals onto a silica-based (Crea + TOA)/SiO2-P adsorbent from simulated high level liquid waste of PUREX reprocessing. AU - Xu, Yuanlai. AU - Kim, Seong Yun. AU - Ito, Tatsuya. AU - Tada, Tsutomu. AU - Hitomi, Keitaro. AU - Ishii, Keizo. PY - 2013/7/1. Y1 - 2013/7/1. N2 - To separate platinum group metals (PGMs) from high level liquid waste (HLLW), a novel silica-based (Crea + TOA)/SiO2-P adsorbent was synthesized by impregnating Crea (N′,N′-di-n-hexyl- thiodiglycolamide) and TOA (trioctylamine) two extractants into the macroporous SiO2-P support with a mean diameter of 60 μm. Adsorption properties and behavior of PGMs from simulated HLLW onto the novel silica-based (Crea + TOA)/SiO2-P adsorbent were investigated by batch method. It was found that (Crea + TOA)/SiO2-P adsorbent exhibited good adsorption selectivity for PGMs over the other tested fission product element in a wide HNO3 concentration. This adsorbent showed ...
Adsorption capacity is defined as the volume of gas that can be adsorbed per unit mass of coal at standard pressure. Learn about adsorption isotherms calculations, its concept, Freundlich isotherm & its properties along with freundlich adsorption isotherm calculation.
TY - JOUR. T1 - Protein adsorption mechanisms determine the efficiency of thermally controlled cell adhesion on poly(N -isopropyl acrylamide) brushes. AU - Choi, Sangwook. AU - Choi, Byung Chan. AU - Xue, Changying. AU - Leckband, Deborah E. PY - 2013/1/14. Y1 - 2013/1/14. N2 - This study investigated the impact of the protein adsorption mechanism(s) on the efficiency of thermally controlled cell adhesion and release from poly(N-isopropyl acrylamide) brushes. Large format polymer gradients were used to screen for grafting densities and substrate chemistries that alter both cell adhesion at 37 °C and rapid cell release at 25 °C. In particular, the grafting conditions investigated allowed protein adsorption to the underlying substrate, penetration of the brush only, or adsorption to the outer edge of the film. At an average molecular weight of 30 kDa (degree of polymerization N ∼ 270), the results show that robust protein adsorption to polymer brushes impairs rapid cell release below the lower ...
Based upon the adsorbate-adsorbent interactions due to pore size distribution and surface heterogeneity, as characterized by the adsorption isotherms, the adsorption phenomenon has many industrial and environmental applications. These adsorption isotherms are very important to define the information related to the equilibrium uptake of adsorbate-adsorbent pair. Due to the presence of different energy distribution of adsorption sites, pore size distribution, surface area availability and surface heterogeneity, of each of the adsorbent-adsorbate pair, these isotherms are categorized into six types by the International Union of Pure and Applied Chemistry and so far, in the literature, there is no generalized adsorption isotherm model available that can define and predict the behavior of all adsorption isotherm types. In this study, a universal adsorption isotherm model is developed based upon the energy distribution function of the available adsorption sites and the pore size. The proposed model is ...
A new kind of Fe-Si adsorbent was synthesized by iron oxide and diatomite after calcining and hydrothermal process. The influences of the initial Cu2+ concentration, pH and adsorption time on the Cu2+ removal efficiency were discussed. Three adsorption empirical kinetics equations and two thermodynamics equations were used to simulate the adsorption process. The microstructures of newly developed copper removal materials and properties of copper removal are characterized in details by SEM and EDS. Adsorption mechanism of the adsorbent was discussed. The suitable pH value for Cu2+ removal is 5.0 to 6.0 and the adsorption capacity increases with increasing the initial Cu2+ concentration. The adsorption kinetics of the adsorbent could be better described by pseudo second order kinetic model, whereas the adsorption isotherms highly conform to the Freundlich equation. The main crystalline phase of the adsorbent is Fe(SiO3) which can build porous structures conducive to the Cu2+ adsorption ...
Adsorption characteristics of light gases on basalt rock-based zeolite 4A: The adsorption characteristics of light gases on basalt rock-based zeolite 4A (BR zeo
In the mixing process of concrete, the addition of auxiliary cementitious building materials can improve the performance of concrete while saving resources, but due to the compatibility problem of raw materials, there shall occur poor fluidity and abnormal setting etc. for the early-period concrete. For this, based on the adsorption mechanism of water reducer on auxiliary cementitious building materials, this paper carries out the study on the adsorption characteristics of three kinds of polycarboxylate superplasticizer (PCS) on the surface of fly ash, and solves the problem of relationship between the PC dosage/adsorption capacity and particle size of fly ash. The results show that the PC structure has a significant influence on the adsorption capacity, and its adsorption capacity on the surface of fly ash gradually increases and becomes saturated with the increase of its dosage. This study is of great significance for the selection of water reducer and the dosage application ...
Isotherms, Kinetics and Thermodynamic Parameters Studies of New Fuchsin Dye Adsorption on Granular Activated Carbon dye adsorption;adsorption isotherm;adsorption thermodynamics;adsorption kinetics;adsorption equilibrium; Batch adsorption studies including equilibrium, kinetics and thermodynamic parameters for the adsorption of new fuchsin dye using granular activated carbon were investigated with varying the operating variables such as initial concentration, contact time and temperature. Equilibrium adsorption data were fitted into Langmuir, Freundlich, Dubinin-Radushkevich and Temkin isotherms. Adsorption equilibrium was mostly well described by Langmuir Isotherm. From the estimated separation factor of Langmuir ($R_L$ = 0.023), and Freundlich (1/n = 0.198), this process could be employed as an effective treatment for the adsorption of new fuchsin dye. Also based on the adsorption energy (E = 0.002 kJ/mol) from Dubinin-Radushkevich isotherm and the adsorption heat constant (B = 1.920 J/mol) from
TY - JOUR. T1 - Surface characterization of the TiClx/MgCl2 model Ziegler-Natta polymerization catalysts. T2 - Adsorption site studies using mesitylene thermal desorption. AU - Kim, Seong. AU - Tewell, Craig R.. AU - Somorjai, Gabor A.. PY - 2000/11/28. Y1 - 2000/11/28. N2 - Temperature-programmed desorption (TPD) of physisorbed mesitylene molecules has been used as a nondestructive surface probe to distinguish the surface adsorption sites of model Ziegler-Natta polymerization catalysts. A MgCl2-supported titanium chloride film (TiClx/MgCl2) was fabricated on an inert gold substrate by codeposition of Mg metal and TiCl4 from the gas phase. The mesitylene TPD probe revealed two types of surface adsorption sites. The dominant site was attributed to the basal plane of these halide crystallites. The minor site could be tentatively attributed to a defective structure at the basal plane boundaries or other crystal planes. Due to the chlorine termination nature of the catalyst surface, the metal ions ...
The purpose of this study was to elucidate the characteristics and mechanisms of adsorption and desorption for heavy metals by micro and nano-sized biogenic CaCO3 induced by Bacillus subtilis, and the pH effect on adsorption was investigated. The results showed that the adsorption characteristics of Cd2+ and Pb2+ are well described by the Langmuir adsorption isothermal equation, and the maximum adsorption amounts for Cd2+ and Pb2+ were 94.340 and 416.667 mg/g, respectively. The maximum removal efficiencies were 97% for Cd2+, 100% for Pb2+, and the desorption rate was less than 3%. Further experiments indicated that the biogenic CaCO3 could maintain its high adsorption capability for heavy metals within wide pH ranges (3-8). The FTIR and XRD results showed that, after the biogenic CaCO3 adsorbed Cd2+ or Pb2+, it did not produce a new phase, which indicated that biogenic CaCO3 and heavy metal ions are governed by a physical adsorption process, and the high adsorptive capacity of biogenic CaCO3 for Cd2+
This book provides researchers and graduate students with an overview of the latest developments in and applications of adsorption processes for water treatment and purification. In particular, it covers current topics in connection with the modeling and design of adsorption processes, and the synthesis and application of cost-effective adsorbents for the removal of relevant aquatic pollutants. The book describes recent advances and alternatives to improve the performance and efficacy of this water purification technique. In addition, selected chapters are devoted to discussing the reliable modeling and analysis of adsorption data, which are relevant for real-life applications to industrial effluents and groundwater. Overall, the book equips readers with a general perspective of the potential that adsorption processes hold for the removal of emerging water pollutants. It can readily be adopted as part of special courses on environmental engineering, adsorption and water treatment for upper ...
Discharge of untreated industrial wastewater containing heavy metals such as Pb2+ is hazardous to the environment due to their high toxicity. This study reports on the adsorption, desorption, and kinetic study on Pb2+ removal from aqueous solutions using wood/Nano-manganese oxide composite (WB-NMO). The optimum pH, contact time and temperature for adsorption were found to be 5.0, 4 h and 333 K, respectively. Pseudo-second-order kinetics best described the adsorption process with an initial sorption rate of 4.0 mg g min-1, and a half-adsorption time t1/2 of 31.6 min. Best fit for adsorption isotherm was obtained with the Brunauer-Emmett-Teller (BET) model with a maximum adsorption capacity of 213 mg/g for an initial metal concentration of 60 mg/L. Both intra-particle diffusion and film diffusion contribute to the rate-determining step. Desorption experiments with 0.5 mol/L HCl, inferred the reusability of the composite. Adsorption experiment of Pb2+ from industrial wastewater confirmed that the prepared
The competitive adsorption of toluene and n-alkanes at binary solution/silica interfaces was studied at room temperature using IR-visible sum frequency generation vibrational spectroscopy. The Surface coverage of toluene for toluene-pentane, toluene-heptane, and toluene-tetradecane mixtures was measured over the complete mole fraction range from 0 to 1. The competitive adsorption process was reversible, and the toluene coverage only depended oil the bulk mole fraction, not on the history of the system. The estimated molar adsorption free energy of toluene is 3.4 +/- 0.3, 1.8 +/- 0.3, and 0.84 +/- 0.3 kJ/mol higher than pentane, heptane, and tetradecane, respectively. Overall, toluene competes favorably on silica, and the molar adsorption free energy of alkanes increases as the chain length increases. It is consistent with the observed SFG spectra, indicating that the alkanes lie flat on the silica surface.. ...
J Mater Sci. DOI 10.1007/s10853-014-8333-x. Adsorption characteristics of noble metals on the strongly basic anion exchanger Purolite A-400TL. A. Wolowicz • Z. Hubicki. Received: 14 March 2014/Accepted: 16 May 2014. © The Author(s) 2014. This article is published with open access at Springerlink.com. Abstract Ion exchange is an alternative process for uptake of noble metals from aqueous solutions. In the present study, the sorption ofPd(II), Pt(IV), and Au(III) ions from aqueous solution was investigated by using Purolite A-400TL (strongly basic anion exchanger, gel, type I) in a batch adsorption system as a function of time (1 min-4 h). Initial Pd(II) concentration (100-1000 mg/L), beads size (0.425-0.85 mm), rate of phases mixing (0-180 rpm), and temperatures (ambient, 313 K) were taken into account during the Pd(II) sorption process. Moreover, the column flow adsorption study was carried out, and the breakthrough curves were obtained for Pd(II) ions. The equilibrium, kinetic, desorption, ...
The adsorption of paracetamol and non-steroidal anti-inflammatory drugs (ibuprofen and naproxen) on ordered mesoporous carbons (OMC) and, for comparison, on commercial activated carbon, were investigated in this work. OMC adsorbents were obtained by the soft-templating method and were characterized by low-temperature nitrogen adsorption and scanning electron microscopy (SEM). The effects of contact time and initial concentration of organic adsorbates on the adsorption were studied. The contact time to reach equilibrium for maximum adsorption was 360 min for all the studied adsorbates. The adsorption mechanism was found to fit pseudo-second-order and intra particle-diffusion models. Freundlich, Langmuir and Langmuir-Freundlich isotherm models were used to analyze equilibrium adsorption data. Based on the obtained experimental data, the adsorption isotherm in the applied concentration range for all the studied adsorbates was well represented by the Freundlich-Langmuir model. The adsorption ability of
The ability of commercial activated carbon to adsorb Pb2+ from aqueous solution has been investigated through batch experiments. The adsorption of lead onto commercial activated carbon has been found to depend on adsorbent dose, initial concentration and contact time. The experiments were carried out at natural solution pH. Equilibrium data fitted well with the Langmuir model and Freundlich model with a maximum adsorption capacity of 23.81 mg of Pb/g of commercial activated carbon. The experiments showed that the highest removal rate was 92.42% for Pb2+ under optimal conditions. The sorption of Pb2+ on commercial activated carbon was rapid during the first 30 min and the equilibrium attained within 60 min. The kinetic processes of Pb2+ adsorption on commercial activated carbon were described by applying pseudo-first-order and pseudo-second-order kinetic models. The kinetic data for the adsorption process obeyed a pseudo-second-order kinetic model, suggesting that the adsorption process is ...
During the last years, the authors have synthesized, characterized, and studied the adsorption properties of nitroprussides, Prussian blue analogues, akaganeites, MeAPOs, metal-organic frameworks, and extremely high specific surface amorphous silica, which allowed the storage of about 11 wt.% of hydrogen in the form of ammonia. In this sense, using the solid-state reaction method, sol-gel methodologies, together with aluminosilicate, high silica and non-aluminosilicate zeolite synthesis methods, were described, moreover was explained how to prepare active carbons along with the synthesis of Prussian blue analogues (PBAs) and nitroprussides (NPs). In addition, the characterization of the materials of interest applying X-ray diffraction, thermogravimetric analysis, DRIFTS, and room-temperature Mossbauer spectrometry was discussed. Besides, the concepts that define physical adsorption and examples of adsorption data, which were tested with the help of the Dubinin, osmotic adsorption and Langmuir-type
Our understanding on how ash particles in volcanic plumes react with coexisting gases and aerosols is still rudimentary, despite the importance of these reactions in influencing the chemistry and dynamics of a plume. In this study, six samples of fine ash (,100 mgrm) from different volcanoes were measured for their specific surface area, as, porosity and water adsorption properties with the aim to provide insights into the capacity of silicate ash particles to react with gases, including water vapour. To do so, we performed high-resolution nitrogen and water vapour adsorption/desorption experiments at 77 K and 303 K, respectively. The nitrogen data indicated as values in the range 1.1-2.1 m2/g, except in one case where a as of 10 m2/g was measured. This high value is attributed to incorporation of hydrothermal phases, such as clay minerals, in the ash surface composition. The data also revealed that the ash samples are essentially non-porous, or have a porosity dominated by macropores with ...
The adsorption characteristics of pure water vapor onto two different types of silica gel at temperatures from (298 to 338) K and at different equilibrium pressures between (500 and 7000) Pa were experimentally studied by a volumetric technique. The thermophysical properties such as the skeletal density, Brunauer-Emmett-Teller surface area, pore size, pore volume, and total porosity of silica gel were determined. The Tóth isotherm model is found to fit all of the experimental data within the experimental errors. The experimental isotherms and the computed enthalpies of adsorption are compared with those of various researchers and found to be consistent with a chiller manufacturers data ...
In this paper, wool carpet dye adsorption properties of nanoporous activated carbon materials (NCMs) prepared from bamboo agro-product is reported. Bamboo cane powder was chemically activated with phosphoric acid at different temperatures (400, 500, and 600 °C) at an impregnation ratio of 1:1. We found that the specific surface area and the total pore volume of NCM increases with temperature giving the highest surface area and pore volume ca. 2130 m2·g−1 and 2.69 cc·g−1 at 600 °C. Owing to superior surface textural properties, bamboo-derived NCM showed excellent adsorption capacity for wool carpet dyes Lanasyn orange (LO) and Lanasyn gray (LG). The adsorption phenomena could be described by Langmuir/Freundlich adsorption isotherm models. The maximum adsorption capacity was ca. 2.60 × 103 and 3.04 × 103 mg·g−1 for LO and LG, respectively. The adsorption followed pseudo second order kinetics with the second order rate constant of 1.24 × 10−3 g·mg−1·min−1 (LO) and 7.69 × 10−4 g·mg
Background: Effective bimolecular adsorption of proteins onto solid matrices is characterized by in-depth understanding of the biophysical features essential to optimize the adsorption performance, Results: The adsorption of bovine serum albumin (BSA) onto anion-exchange Q-sepharose solid particulate support was investigated in batch adsorption experiments, Adsorption kinetics and isotherms were developed as a function of key industrially relevant parameters such as polymer loading, stirring speed, buffer pH, protein concentration and the state of protein dispersion (solid/aqueous) in order to optimize binding performance and adsorption capacity, Experimental results showed that the first order rate constant is higher at higher stirring speed, higher polymer loading, and under alkaline conditions, with a corresponding increase in equilibrium adsorption capacity, Increasing the stirring speed and using aqueous dispersion protein system increased the adsorption rate, but the maximum protein ...
Due to high biocompatibility and tailorable properties, DNA-based nanostructures are widely studied in biosensor and nanomedicine applications. The restriction for using DNA-based nanostructures lie in the purification processes which have low product yield and tedious steps involved. MoS2 nanosheets are chosen to test for its purification efficiency as MoS2 is shown to have discriminating properties between single stranded DNA and double stranded DNA. Adsorption studies of different DNA nanostructures are tested to see the adsorption capacity of MoS2. From the adsorption studies, it has been observed that MoS2 has high affinity to plasmid DNA, so the use of MoS2 as a gene carrier is tested for its delivery performance ...
Batch adsorption experiments were conducted to investigate equilibrium, kinetic and thermodynamics of the sorption of Methylene Blue onto Fly Ash modified with various concentrations of hydrochloric acid (FAHC-4, FAHC-3, FAHC-2 and FAHC-1). Equilibrium data was best described by the Freundlich isotherm model which suggests adsorbents had heterogeneous surfaces therefore multilayer adsorption occurred in all cases. Fly Ash modified with 1M HCl exhibited the highest adsorption capacity (9.8 mg/L) and Fly Ash modified with 4M HCl had the least adsorption capacity (4.4mg/L). Kinetic data was best described by the pseudo-second-order kinetic model which means adsorption processes were controlled by chemisorption. Boyd kinetic model plots revealed that the rate determining step of each sorption process followed the film diffusion mechanism in which adsorbate ions travelled towards the external surfaces of adsorbents due to electrostatic interactions between chemically modified Fly Ash and adsorbate ...
Abstract The adsorption of four substances and their binary mixture is investigated via the terahertz time domain spectroscopy (THz-TDS). The selected unary compound (ethanol, acetone, ethyl acetate, and n-propyl acetate) and binary mixture (solution 1 is composed of ethanol and acetone, and solution 2 is composed of ethyl acetate and n-propyl acetate) exhibit different adsorption behaviors with varied polarities. In comparison with single component, solution 1 shows shorter adsorption equilibrium time, faster adsorption rate, and stronger adsorption capacity, which conform to a synergistic adsorption mechanism, while the competitive behavior is attributed to the slower adsorption in solution 2. In addition, the pseudo-second-order equation with terahertz parameter is used to assess the rate of binary component organics. The present results indicate a further understanding of multicomponent adsorption mechanisms ...
For the first time, we have used a metal oxide-coated quartz crystal microbalance (QCM) to measure Cs+ adsorption onto illuminated and un-illuminated mesoporous TiO2 (m-TiO2) films by microgravimetric means in-situ. In the simplest case, such experiments yield two parameters of interest: K, the Langmuir adsorption coefficient and mmax the maximum mass of adsorbate to form a complete monolayer at the m-TiO2-coated quartz crystal piezoelectric surface. Importantly, we have found that illumination of the m-TiO2 film with ultra bandgap light results in an increase in mmax i.e. illumination allows for greater adsorption of substrate to occur than in the dark. Our studies also show that under illumination, K also increases indicating a higher affinity for surface adsorption. The photoinduced change in mmax and K are thought to be due to an increase in surface bound titanol groups, thus increasing the number of available adsorption sites - and so providing evidence to support the notion of photoinduced ...
TY - JOUR. T1 - Sol-gel synthesis and gas adsorption properties of CuCl modified mesoporous alumina. AU - Wang, Y.. AU - Lin, Y. S.. PY - 1998. Y1 - 1998. M3 - Article. VL - 1. SP - 185. EP - 195. JO - J. Sol-Gel Sci. Tech.. JF - J. Sol-Gel Sci. Tech.. ER - ...
This thesis presents experimental studies of polyelectrolyte adsorption on oppositely charged surfaces, where substrates of both silica and bleached softwood kraft pulp were used. A major aim of this research was to characterise the conformation of adsorbed layers of cationic polyacrylamide (CPAM), in comparison to cationic dextran (Cdextran), and relate this information to the binding capacity of colloidal silica. A second aim in this thesis was to study the kinetics of the sequential adsorption of polyamide epichlorohydrine (PAE) and carboxymethyl cellulose (CMC) on pulp fibres, and to determine the adsorption isotherms for the layer-by-layer deposition of polyelectrolytes on pulp fibres.. The adsorption of CPAM on silica surfaces was studied using stagnation point adsorption reflectometry and quartz crystal microgravimetry to determine its adsorption kinetics as well as the dependencies of polyelectrolyte charge densities, pH, and NaCl concentration on saturation adsorption. The conformation ...
Read "Synthesis, Characterization, and Adsorption Properties of a Graphene Composite Sand (GCS) and Its Application in Remediation of Hg(II) Ions, Water, Air, Soil Pollution" on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.
Fingerprint Dive into the research topics of Control of interpenetration: Via in situ lithium incorporation in MOFs and their gas adsorption properties and selectivity. Together they form a unique fingerprint. ...
TY - JOUR. T1 - Nanoscale control of layer thickness for EL devices by mass-controlled layer-by-layer sequential adsorption process. AU - Shiratori, Seimei. AU - Yamada, Masayoshi. AU - Ito, Takahiro. AU - Wang, Tom C.. AU - Rubner, Michael F.. PY - 2000/12/1. Y1 - 2000/12/1. N2 - A mass controlled layer-by-layer sequential adsorption process for polyelectrolytes was newly developed for the fabrication of functional devices using ultra-thin organic film formed by various polymers of different polarity of charge. In this study hydrophobic Ruthenium complex monomer (tris(bipyridyl) ruthenium(II) hexafluorophosphate) was micelle-wrapped with an anionic surfactant, sodium dodecylbenzenesulfonate, and was assembled with PAH (poly (allylamine hydrochloride)), which has the opposite charge, on ITO substrates. With this method, we succeeded in fabricating ultra-thin organic films even when the adsorption material is not polymer but monomer. Moreover it was found that the film thickness of the ...
This thesis presents experimental studies of polyelectrolyte adsorption on oppositely charged surfaces, where substrates of both silica and bleached softwood kraft pulp were used. A major aim of this research was to characterise the conformation of adsorbed layers of cationic polyacrylamide (CPAM), in comparison to cationic dextran (Cdextran), and relate this information to the binding capacity of colloidal silica. A second aim in this thesis was to study the kinetics of the sequential adsorption of polyamide epichlorohydrine (PAE) and carboxymethyl cellulose (CMC) on pulp fibres, and to determine the adsorption isotherms for the layer-by-layer deposition of polyelectrolytes on pulp fibres.. The adsorption of CPAM on silica surfaces was studied using stagnation point adsorption reflectometry and quartz crystal microgravimetry to determine its adsorption kinetics as well as the dependencies of polyelectrolyte charge densities, pH, and NaCl concentration on saturation adsorption. The conformation ...
... The removal of Ni(II) by foam fractionation is brought about by the electrostatic mechanism. From removal and zeta potential measurements, it clearly demonstrates that Ni**2** plus and NiOH** plus ions become associated with the dodecylsulfonate coated (negative charge) N//2 gas bubbles. The optimal Ni(II) to NaDS (molar ratio) is 0. 2. The Ni**2** plus species forms moderately strong complexes with dodecylsulfonate ions.
We use Ca doping during growth of one- and two-monolayer-thick MgO films on Ag(100) to identify the adsorption sites of individual adatoms with scanning tunnelingmicroscopy. For thiswe combine atomic resolution images of the bare MgO layer with images of the adsorbates and the substitutional Ca atoms taken at larger tip-sample distance. For Ho atoms, the adsorption sites depend on MgO thickness. On the monolayer, they are distributed on the O and bridge sites according to the abundance of those sites, 1/3 and 2/3, respectively. On the MgO bilayer, Ho atoms populate almost exclusively the O site. A third species adsorbed on Mg is predicted by density functional theory and can be created by atomic manipulation. Au atoms adsorb on the bridge sites for both MgO thicknesses, while Co and Fe atoms prefer the O sites, again for both thicknesses.. ...
It was found that slow desorption kinetics determine the cyclic working capacity for CO2 and H2O. Furthermore, four different adsorption sites are required to describe the observed complex adsorption behaviour of CO2 and H2O and their cyclic working capacity was determined based on many different carefully designed TGA and PBR breakthrough experiments. The sorption model includes two independent adsorption sites for H2O and CO2 (sites A and B resp.) and another site which can be occupied by both CO2 and H2O, where one component replaces the other (site C). A fourth site (site D) describes the general higher adsorption capacity of the sorbent if H2O and CO2 are fed together to the sorbent ...
Molecularly imprinting (MI) hydrogels for selective adsorption of trypsin are reported. The trypsin imprinted hydrogels were prepared using a polyethylene glycol (PEG)-based dimethacrylate as a crosslinker and anionic functional monomers. The hydrogel prepared without any functional monomers showed significantly low ability to adsorb a variety of proteins. We optimized the concentration and the length of PEG units of the crosslinkers to achieve the complete removal of the template molecule and suitable selective adsorption. Additionally, the functional monomers chosen were anionic since the template, trypsin, is a basic protein. The adsorption tests for proteins, done on the prepared MI gels, indicated that the MI gel prepared with sodium allyl sulfonate (AS) as a functional monomer showed much higher selective adsorption for trypsin, even though a mixture of trypsin and cytochrome c was used as the protein solution. The selective adsorption was more effective in a NaCl solution in which the ...
Atomic oxygen adsorption on a pure aluminum terminated Al 9Co2(001) surface is studied by first-principle calculations coupled with STM measurements. Relative adsorption energies of oxygen atoms have been calculated on different surface sites along with the associated STM images. The local electronic structure of the most favourable adsorption site is described. The preferential adsorption site is identified as a bridge type site between the cluster entities exposed at the (001) surface termination. The Al-O bonding between the adsorbate and the substrate presents a covalent character, with s-p hybridization occurring between the states of the adsorbed oxygen atom and the aluminum atoms of the surface. The simulated STM image of the preferential adsorption site is in agreement with experimental observations. This work shows that oxygen adsorption generates important atomic relaxations of the topmost surface layer and that sub-surface cobalt atoms strongly influence the values of the adsorption ...
TY - JOUR. T1 - Adsorption and desorption kinetics for hydrophilic and hydrophobic vapors on activated carbon. AU - Fletcher, A.J.. AU - Yuzak, Y.. AU - Thomas, K.M.. PY - 2006/4. Y1 - 2006/4. N2 - Adsorption dynamics are of fundamental importance in applications of adsorbents in real situations. The adsorption/desorption characteristics of a series of adsorbates, with varying hydrophilic/hydrophobic and structural characteristics, for activated carbon BAX950, were investigated for temperatures in the range 288-323 K. These data provide a comprehensive kinetic study of adsorption/desorption for an activated carbon. The results are discussed in relation to the adsorbent pore structure and functional group concentration, adsorptive structure and adsorption mechanism. The study provides evidence for a compensation effect where activation energy and ln(pre-exponential factor) parameters obtained from the Arrhenius equation exhibit a linear correlation.. AB - Adsorption dynamics are of fundamental ...
In order to shed some light on DNA preservation over time in skeletal remains from a physicochemicalviewpoint, adsorption and desorption of DNA on a well characterized synthetic apatite mimicking boneand dentin biominerals were studied. Batch adsorption experiments have been carried out to determinethe effect of contact time (kinetics), DNA concentration (isotherms) and environmentally relevant factorssuch as temperature, ionic strength and pH on the adsorption behavior. The analogy of the nanocrystallinecarbonated apatite used in this work with biological apatite was first demonstrated by XRD, FTIR, andchemical analyses. Then, DNA adsorption kinetics was fitted with the pseudo-first order, pseudo-secondorder, Elovich, Ritchie and double exponential models. The best results were achieved with the Elovichkinetic model. The adsorption isotherms of partially sheared calf thymus DNA conformed satisfacto-rily to Temkins equation which is often used to describe heterogeneous adsorption behavior ...
A quartz crystal microbalance with dissipation (QCM-D) and an optical reflectometer (OR) have been used to investigate the adsorption behavior of Laponite and Ludox silica nanoparticles at the solid-liquid interface. The adsorption of both Laponite and Ludox silica onto poly(diallyldimethylammonium chloride) (PDADMAC)-coated surfaces over the first few seconds were studied by OR. Both types of nanoparticles adsorbed rapidly and obtained a stable adsorbed amount after only a few minutes. The rate of adsorption for both nanoparticle types was concentration dependent. The maximum adsorption rate of Ludox nanoparticles was found to be approximately five times faster than that for Laponite nanoparticles. The QCM data for the Laponite remained stable after the initial adsorption period at each concentration tested. The observed plateau values for the frequency shifts increased with increasing Laponite particle concentration. The QCM data for the Ludox nanoparticles had a more complex long-time ...
Attapulgite clay also known as palygorskite is a mineral clay which possess good adsorption properties based on its adsorption capacity, porous structure and moderate cation exchange properties. The study investigated the effectiveness of naturally occurring and hydrochloric acid modified attapulgite as adsorbents for Cr (VI) remediation in wastewater. The physical properties of the clay were characterized using a range of techniques. X-ray diffraction confirmed the purity of the clay while BET analysis indicated an increase in surface area from 131.4 to 183.2 m2/g after acid modification. The modified attapulgite was predicted to have an adsorption capacity of 75 mg/g compared to 2.1 mg/g for the naturally occurring attapulgite. The increase in adsorption capacity was attributed to a change in surface area as well as changes in the surface chemistry of the clay. The adsorption isotherms were best described by the Langmuir mono-layer adsorption model while the kinetics fit the Langren first ...
Cadmium (Cd) concentration in soil solution and its bioavailability is controlled by sorption-desorption reactions. The objective of this research was to compare Cd adsorption behavior in six calcareous and four acid soils. Soil samples were equilibrated with 0.01 M Ca(NO3)2 containing 25 to 3200 mg Cd L−1. Results showed that the tendency for adsorption was high at low Cd concentrations (0-400 mg L-1), but decreased as the Cd increased (400-3200 mg L-1). Among five equations evaluated, Freundlich, Langmuir, and Gunary equations best described Cd adsorption in both calcareous and acid soils as indicated by high values for coefficient of determination (R2) and low values for standard error of estimate (SE). Stepwise regression equations between constants of the best-fitted models and soil properties revealed that cation exchange capacity (CEC) and clay content were the most important soil properties affecting Cd adsorption behavior in calcareous soils, whereas in acid soils Cd adsorption was mainly
Oxygen and carbon monoxide adsorption studies were carried out in ultra high vacuum on vapor deposited polycrystalline platinum films with a |111| fiber axis and on monocrystalline (111) palladium films. The techniques of Auger electron spectroscopy (AES), electron loss spectroscopy (ELS) and thermal desorption spectroscopy (TDS) were used. A new form of electron diffraction pattern, namely Kikuchi rings, was also observed from these films. Oxygen adsorption studies on the Pt films showed the existence of two forms of adsorbed oxygen. TDS of carbon monoxide adsorbates showed only one peak and resulted in the development of a new loss line in the ELS spectrum. Electron beam irradiation decomposed the adsorbed CO resulting in a shape change for the carbon Auger line. The rate of reaction for carbon monoxide oxidation was found to be temperature dependent, thereby supporting the Langmuir-Hinshelwood mechanism for CO oxidation. Transmission electron microscope (TEM) replica studies of vapor deposited (111)
Sulphate adsorption and desorption can delay the response in soil acidity against changes in acid input. Here we evaluate the use of an extended Freundlich equation for predictions of pH-dependent SO4 adsorption and desorption in low-ionic strength soil systems. Five B horizons from Spodosols were subjected to batch equilibrations at low ionic strength at different pHs and dissolved SO4 concentrations. The proton coadsorption stoichiometry (eta), i.e. the number of H+ ions co-adsorbed for every adsorbed SO42- ion, was close to 2 in four of five soils. This enabled the use of a Freundlich equation that involved only two adjustable parameters (the Freundlich coefficient K-F and the non-ideality parameter m). With this model a satisfactory fit was obtained when only two data points were used for calibration. The root-mean square errors of log adsorbed SO4 ranged from 0.006 to 0.052. The model improves the possibility to consider SO4 adsorption/desorption processes correctly in dynamic soil ...
The composite media, ZeliacTM was developed with the initial aim to provide low cost adsorbent with promising adsorption capacity. This study was conducted to investigate the removal of UV absorbance at 254 nm (UV254) in Kerian river water using ZeliacTM as the media. Batch experiments study was carried out to determine the optimum removal of UV254 by ZeliacTM. The experimental data were fitted to Langmuir and Freundlich isotherms to investigate the adsorption mechanism. The results from batch study exhibit that ZeliacTM is capable to remove 74.4% UV254 at the dosage of 7g/100 ml. Linear isotherm analysis suggests that the best fitting linear line is Freundlich isotherm with R2 values of 0.9294 indicating multilayer adsorption. Similarly, non-linear regression analysis reveals that the adsorption of UV254 by ZeliacTM is attributed by physisorption. The non-linear Freundlich isotherm gives a better fit to the adsorption of UV254 than Langmuir isotherm with R2 values of 0.9488. The results are ...
TY - JOUR. T1 - Optimization of adsorption isotherm types for desiccant air-conditioning applications. AU - Sultan, Muhammad. AU - Miyazaki, Takahiko. AU - Koyama, Shigeru. PY - 2018/6. Y1 - 2018/6. N2 - The present study investigates five kinds of adsorbents for desiccant air-conditioning (DAC) applications. Each adsorbent yield distinctive water vapor adsorption isotherm that can be categorized as type-I, type-II, type-III, type-V, and type-linear on the basis of the International Union of Pure and Applied Chemistry (IUPAC) classification. Ideal DAC cycle is evaluated for the air-conditioning (AC) applications, and steady-state moisture cycled (MCSS) is estimated by means of adsorption isobars. Results showed that the adsorbent enabling type-linear adsorption isotherm gives maximum MCSS for industrial AC processes of matches manufacturing/drying/storage, rubber dipped goods storage and photo studio drying room. However, adsorbent enabling type-V adsorption isotherm is found the optimum ...
adsorption experimental methods to study the micropore types and pore structures and their effects on the methane adsorption capacity of organic-rich shales found in the Fenggang block in northern Guizhou Province. The results indicate that the microscopic surface porosity of the lower Cambrian Niutitang Formation ranges from 2.88% to 5.34%, with an average value of 3.86%. Based on nitrogen adsorption methods, the range of the average pore size distribution is 4.6-9.491 nm, with an average value of 6.68 nm. All of the samples exhibit significant unimodal distributions. The main pore size is less than 10 nm, and these pores account for most of the mesopore volume, which is generally consistent with the NMR results. The methane adsorption capacity of the shale samples gradually increases in the range of 0-8 MPa at 30°C and reaches a maximum at approximately 10 MPa. Positive correlations were found between the gas content and specific surface area, total pore volume, and micropore volume. These ...
TY - JOUR. T1 - Effect of surface strain on oxygen adsorption on Zr (0 0 0 1) surface. AU - Wang, X.. AU - Khafizov, M.. AU - Szlufarska, I.. PY - 2014/1/1. Y1 - 2014/1/1. N2 - The effect of surface strain on oxygen adsorption on Zr (0 0 0 1) surface is investigated by density functional theory (DFT) calculations. It is demonstrated that both surface strain and interactions between oxygen adsorbates influence the adsorption process. Oxygen binding to zirconium becomes stronger as the strain changes from compressive to tensile. When oxygen coverage is low and the oxygen interactions are negligible, surface face-centered cubic sites are the most stable for O binding. At high coverage and under compression, octahedral sites between second and third Zr layers become most favorable because the interactions between adsorbates are weakened by positive charge screening. Calculations with both single-layer adsorption model and multiple-layer adsorption model demonstrate that compressive strain at the ...
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Enzyme adsorption onto carriers functions based on chemical and physical phenomena such as van der Waals forces, ionic ... Many immobilization techniques exist, such as adsorption, covalent binding, affinity, and entrapment. Ideal immobilization ... Jesionowski, Teofil; Zdarta, Jakub; Krajewska, Barbara (2014-08-01). "Enzyme immobilization by adsorption: a review". ... and high adsorption capacity. Enzymes typically constitute a significant operational cost for industrial processes, and in many ...
Die Adsorption." (Physical-chemical studies of chlorophyll. Adsorption.) Berichte der Deutschen botanischen Gesellschaft, vol. ... In expanded bed adsorption, a fluidized bed is used, rather than a solid phase made by a packed bed. This allows omission of ... Expanded-bed adsorption (EBA) chromatography is a convenient and effective technique for the capture of proteins directly from ... When we make one solvent immobile (by adsorption on a solid support matrix) and another mobile it results in most common ...
He used liquid-adsorption column chromatography with calcium carbonate as adsorbent and petrol ether/ethanol mixtures as eluent ... It's still not known whether in the case of Tsvet's adsorption analysis ([which functions] on a small scale), this change of ... Adsorption.), Berichte der Deutschen botanischen Gesellschaft, 24 : 316-323. On page 322, Tsvet coins the term "chromatography ... Adsorption analysis and chromatographic method. Application to the chemistry of chlorophyll.), Berichte der Deutschen ...
Adsorption. 22 (4): 366-375. doi:10.1007/s10450-015-9740-2. ...
Adsorption, 2016. 22 (8): 1147-1155. DOI:10.1007/s10450-016-9838-1.. ...
This type of adsorption system is therefore functionally a nitrogen scrubber leaving the other atmospheric gases to pass ... To meet that need, another process, called vacuum swing adsorption (VSA), has been developed by Air Products. This process uses ... Oxygen concentrators utilize a molecular sieve to adsorb gases and operate on the principle of rapid pressure swing adsorption ... Oxygen concentrators typically use pressure swing adsorption (PSA) technology and are used very widely for oxygen provision in ...
Fehime Cakicioglu-Ozkan; Semra Ulku (January 2005). "The effect of HCl treatment on water vapor adsorption characteristics of ... doi:10.1016/S0169-4332(98)00244-X. Semra Ülkü (1993). "Novel Application of Adsorption: Energy Recovery". Studies in Surface ... doi:10.1016/S0167-2991(08)61748-6. Semra Ülkü (1986). "Adsorption heat pumps". Journal of Heat Recovery Systems. 6 (4): 277-284 ... by adsorption on silk fibroin". Separation and Purification Technology. 62 (2): 342-348. doi:10.1016/j.seppur.2008.01.022. ...
In pressure swing adsorption the raffinate refers to the gas which is not adsorbed during the high pressure stage. The species ... Ruthven, Douglas M.; Shamsuzzman Farooq, Kent S. Knaebel (1993). Pressure Swing Adsorption. Wiley-VCH. p. 1. ISBN 9780471188186 ...
... adsorption and surface chemistry; chemistry of water purification; transport of metals and other substances in water; and water ...
Adsorption 4:3-4. (1998) A. Kundu, K. Barnthouse, and S. M. Cramer. Biotech. and Bioeng., 56:119-129. (1997) KA. Kundu, A. A. ... Displacement development in adsorption analysis. Ark. Kemi. Mineral Geol. 16A: 1-18 (1943). G. T. Seaborg. The Transuranium ... the salt-dependent adsorption behavior of these low MW displacers greatly facilitates column regeneration. These displacers ...
In this approach, a liquid extractant is contained within the pores of (adsorption) particles. Usually, the extractant is an ... The basic principle combines adsorption, chromatography and liquid-liquid extraction. The principle of Solvent Impregnated ... Adsorption 14: 357-366. Babic, K.; van der Ham, L.; de Haan, A. (2006). "Recovery of benzaldehyde from aqueous streams using ... "Expansion of adsorption isotherms into equilibrium surface Case 1: solvent impregnated resins (SIR)." React. Funct. Polym. 48 ...
... adsorption, catalysis and electrochemistry; interfacial processes, capillarity and wetting; biomaterials and nanomedicine; and ...
Distribution of adsorption energies and odd adsorption sites. Bonds formed between the adsorbates. Compared to physisorption ... As an instance of adsorption, chemisorption follows the adsorption process. The first stage is for the adsorbate particle to ... Adsorption Physisorption Oura, K.; V. G. Lifshits; A. A. Saranin; A. V. Zotov; M. Katayama (2003). Surface Science, An ... Chemisorption is a kind of adsorption which involves a chemical reaction between the surface and the adsorbate. New chemical ...
... adsorption and ion exchange; gas-solid, liquid-solid and solid-solid operations; biochemical engineering; waste management, ...
Its soil adsorption coefficient (Koc; normalized to soil organic matter content) is 25 cm3/g. Chloropicrin was manufactured for ...
The chemical formula of chlorographene can be given as (CCl)n. Upon chlorine adsorption, graphene's sp2 planar lattice ... Sahin, H (2012). "Chlorine Adsorption on Graphene: Chlorographene". The Journal of Physical Chemistry C. 116 (45): 24075. doi: ...
Bhattacharyya, KG; Gupta, SS (2008). "Adsorption of a few heavy". Advances in Colloid and Interface Science. 140 (2): 114-31. ... expand considerably more than other clays due to water penetrating the interlayer molecular spaces and concomitant adsorption. ...
Comparisons of adsorption rates for zinc ions of CNTs vs. other materials such as commercially available PAC were very ... Li, Y.H.; Wang, S.; Wei, J.; Zhang, X.; Xu, C.; Luan, Z.; Wu, D.; Wei, B. (2002). "Lead adsorption on carbon nanotubes". Chem. ... CNT Membranes show a particular affinity for adsorption by heavy metals ions such as Zn2+, which is toxic to aquatic organisms ... and reusable for 10 cycles of adsorption and deadsorption. CNT filtration has also been shown to adsorb other heavy metals such ...
Duong, Do D (1998). "Fundamentals of Diffusion and Adsorption in Porus Media". Adsorption Analysis: Equilibria and Kinetics. ...
doi:10.1016/0167-7799(91)90064-o. Wahlgren, Marie; Arnebrant, Thomas; Lundström, Ingemar (1995). "The Adsorption of Lysozyme to ... Wahlgren, Marie; Arnebrant, Thomas (1991). "Protein adsorption to solid surfaces". Trends in Biotechnology. 9: 201-208. ... Hydrophilic Silicon Oxide Surfaces: Comparison between Experimental Data and Models for Adsorption Kinetics". Journal of ...
ACS Nano, 2017, X (Y), pp XX-XY doi:10.1021/acsnano.6b08449 Sahin, H (2012). "Chlorine Adsorption on Graphene: Chlorographene ...
Adsorption separation might be possible. In adsorption separation, a mixture of chemicals flows past a porous solid called the ...
ISBN 0-471-58626-9. e.g.: during adsorption process.. ...
One topic of his research is the characterization of adsorption and reactions on well-defined single-crystal surfaces. A second ... "Adsorption of Potassium on Tungsten". Retrieved 28 November 2008. "Partial Oxidation, Complete Combustion, Carbon Chemistry, ... Among many research endeavors, his thesis on alkali metal adsorption was supervised by Professor Robert Gomer. In 1965, he ...
Ewans J. W. (1993). Random and cooperative sequential adsorption. Rev. Mod. Phys., 65, 1281-1329] Poland D., Scheraga H.A. ( ...
Abstract: The adsorption of tris(1,10-phenanthroline)-ruthenium(II) (Ru(phen)32+) by two kinds of colloidally dispersed clays, ... Adsorption Properties of Montmorillonite and Synthetic Saponite as Packing Materials in Liquid-Column Chromatography. Yuji ... Key Words: Adsorption • Electronic absorption • Liquid-column chromatography • Montmorillonite • Ruthenium phenanthroline • ... The electronic spectrum measurements suggested that the electronic states of the complex were more perturbed on adsorption by ...
In this study, the adsorption of Fluoride from aqueous solution onto pretreated zeolite has been studied by using batch test. ... The performances of the Fluoride adsorption with the natural zeolite (i. e., non modified zeolite) were compared with the ... Acidic pH was the better condition for fluoride adsorption and the bicarbonate content cause higher pH values and thus ... Al3+ was particularly found to create adsorption media with high capacity and specificity for fluoride. ...
The heat of water adsorption for zeolites is high. They also possess high adsorption capacity, undergo reversible adsorption/ ... Adsorption. The most fundamental consideration regarding the adsorption of chemical species by zeolites is molecular sieving. ... Adsorption based on molecular sieving, electrostatic fields, and polarizability are always reversible in theory and usually ... All commercially useful zeolites owe their value to one or more of three properties: adsorption, ion exchange, and catalysis. ...
... technique refers to a bioanalytical approach capable of monitoring adsorption reactions at the solid-liquid interface with the ... The quartz crystal microbalance (QCM) technique refers to a bioanalytical approach capable of monitoring adsorption reactions ... 2009) Replacement free electrodeless quartz crystal microbalance biosensor using nonspecific adsorption of streptavidin on ...
Bentonite clay is good adsorption properties. Can absorb as much water as a result of soil looks expansion (Swell ability) high ...
Polymer adsorption[edit]. Main article: polymer adsorption. Adsorption of molecules onto polymer surfaces is central to a ... Portal site mediated adsorption[edit]. Portal site mediated adsorption is a model for site-selective activated gas adsorption ... Polymers may also be adsorbed to surfaces through polyelectrolyte adsorption. Adsorption in viruses[edit]. Adsorption is the ... Adsorption enthalpy[edit]. Adsorption constants are equilibrium constants, therefore they obey the van t Hoff equation: (. ∂. ...
Selective adsorption is the effect when minima associated with bound-state resonances occur in specular intensity in atom- ... The selective adsorption binding energies can supply information on the gas-surface interaction potentials by yielding the ...
The fundamental idea behind spontaneous protein adsorption is that adsorption occurs when more energy is released than gained ... Adsorption (not to be mistaken for absorption) is the accumulation and adhesion of molecules, atoms, ions, or larger particles ... The adsorption of larger biomolecules such as proteins is of high physiological relevance, and as such they adsorb with ... Taking this a step further, implantable devices can be coated with a bioactive material to encourage adsorption of specific ...
... or colours is adsorption by activated carbon. Adsorption is the capacity of a solid particle to attract molecules to its ... Carbon adsorption: An effective method for removing dissolved organic substances that cause tastes, odours, ... Other articles where Carbon adsorption is discussed: water supply system: ... Adsorption is the capacity of a solid particle to attract molecules to its surface. Powdered carbon mixed with water can adsorb ...
The Ea values of these compounds have appeared to be several times lower than the heats of their adsorption on carbon black ... Standard Test Method for Carbon Black-Iodine Adsorption Number. Intr. 1998. PA, USA: ASTM Int., 2013.Google Scholar ... It has been shown that sulfur present in schungite has no effect on the results of determining its adsorption activity and does ... The influence of these compounds on the adsorption activity of schungite with respect to iodine has been investigated. ...
We determine the adsorption energy per adsorbate, , as the difference in total energies of the full system and each fragment ... Included is the adsorption energy , the distance of the methanol O atom from graphene, , the adsorption configuration (C-O axis ... By use of the first-principles vdW-DF method, we calculate adsorption energies and determine adsorption geometries of methanol ... and thus the adsorption properties of methanol affect the adsorption of the other molecule. Gaining access to detailed ...
Adsorption in clusters or at high coverages (less than a monolayer) is found to be preferable, with the methanol C-O axis ... The adsorption energies calculated with vdW-DF are compared with previous DFT-D and MP2-based calculations for single methanol ... Methanol Adsorption on Graphene. Elsebeth Schröder Microtechnology and Nanoscience (MC2), Chalmers University of Technology, ... The adsorption of a single methanol molecule and small methanol clusters on graphene is studied at various coverages. ...
... 2002-01-2345. A dynamic simulation of the ISS CDRA hardware was created using ... Citation: Anderson, M. and Jeng, F., "Adsorption Modeling with ACM: ISS CDRA Simulation," SAE Technical Paper 2002-01-2345, ...
An adsorption apparatus and method of adsorption for treatment of wastewater is disclosed, and comprises an inlet for the ... Adsorption system. 2005-04-28. Parke. 6811703. Methods for adsorption and retention of solvated compounds and ions. 2004-11-02 ... 2. The adsorption apparatus of claim 1 wherein said predetermined size is about 5 microns or greater. 3. The adsorption ... An adsorption apparatus and method of adsorption for treatment of wastewater is disclosed, and comprises an inlet for the ...
Definition of immune adsorption. Provided by Stedmans medical dictionary and Drugs.com. Includes medical terms and definitions ...
506g) Preparation and Its Excellent CO2/CH4/N2 Adsorption Selectivity of Novel Carbon Composites [email protected] ... 506a) CO2 Extraction from Simulated Air Via Temperature Swing Adsorption Using Polymer/Silica Fiber Sorbents ...
Adsorbent, adsorption column and apparatus for pressure swing adsorption separation. February, 2002. Tatsumi et al. ... Next Patent: ADSORPTION COMPOSITION AND PROCESS FOR REMOVING CO FROM MATERIAL STREAMS ...
... ,ARUP Laboratories is a national reference laboratory and a worldwide leader in innovative laboratory ...
... 18 November 2019 13:00-14:00, Cardiff, United Kingdom ...
687c) Adsorption of 5-Hydroxymethyl-Furfural (HMF) From Liquid Water/Dimethyl Sulfoxide (DMSO) Solutions Onto Hydrophobic ... This session presents the most recent advances in the molecular simulations of adsorbents, adsorption phenomena, molecular ... 687i) Investigation of the Critical Point of Adsorption of Polymer Chains On Porous Adsorbents ...
Portal site mediated adsorption. Portal site mediated adsorption is a model for site-selective activated gas adsorption in ... Adsorption of viruses. When a virus infects a cell, the first step is adsorption of the viral particle (virion) on the cell ... Langmuir suggested that adsorption takes place through this mechanism: , where A is a gas molecule and S is an adsorption site ... Isotherms: Quantification of adsorption. Adsorption may be described quantitatively by the use of isotherms. An isotherm shows ...
Polymer adsorptionEdit. Main article: polymer adsorption. Adsorption of molecules onto polymer surfaces is central to a number ... Portal site mediated adsorptionEdit. Portal site mediated adsorption is a model for site-selective activated gas adsorption in ... Adsorption enthalpyEdit. Adsorption constants are equilibrium constants, therefore they obey the van t Hoff equation: (. ∂. ln ... as the fraction of the adsorption sites occupied, in the equilibrium we have: K. =. k. k. −. 1. =. θ. (. 1. −. θ. ). P. ,. {\ ...
... combined the adsorption advantages of RGO and 2-Hydroxypropyltrimethyl ammonium chloride chitosan (HACC). The adsorption... ... The adsorption and desorption of HACC-RGO/CS beads for MO were studied. After three adsorption-desorption cycles, the ... The removal ratios of HACC-RGO sheets reached 92.6% for MO after a 24 h adsorption. The adsorption kinetics, isotherms and ... Lu X, Wang F, Li X, et al. Adsorption and Thermal Stabilization of Pb2+ and Cu2+ by Zeolite[J]. Industrial & Engineering ...
Carbon nanomaterials for gas adsorption. [M L Terranova; Silvia Orlanducci; Marco Rossi, Ph. D.;] -- The increasing interest ... 7. Modeling gas adsorption on carbon nanotubes / Amanda S. Barnard --. 8. Atomistic simulation of gas adsorption in carbon ... Modeling gas adsorption on carbon nanotubes / Amanda S. Barnard -- 8. Atomistic simulation of gas adsorption in carbon ... Carbon nanomaterials for gas adsorption. Author:. M L Terranova; Silvia Orlanducci; Marco Rossi, Ph. D.. ...
Method for thermal swing adsorption and thermally-enhanced pressure swing adsorption Patent Wegeng, Robert S. ; Rassat, Scot D. ... Apparatus for thermal swing adsorption and thermally-enhanced pressure swing adsorption Patent Wegeng, Robert S. ; Rassat, Scot ... Novel methods of thermal swing adsorption and thermally-enhanced pressure swing adsorption are also described. In some aspects ... Novel methods of thermal swing adsorption and thermally-enhanced pressure swing adsorption are also described. In some aspects ...
  • In this study, the adsorption of Fluoride from aqueous solution onto pretreated zeolite has been studied by using batch test. (ac.ir)
  • The performances of the Fluoride adsorption with the natural zeolite (i. e., non modified zeolite) were compared with the pretreated zeolite. (ac.ir)
  • Al3+ and Fe3+ -modified zeolites), Al3+ was particularly found to create adsorption media with high capacity and specificity for fluoride. (ac.ir)
  • Adsorption of fluoride from water by Al3+ and Fe3+ pretreated natural Iranian zeolites', International Journal of Environmental Research , 4(4), pp. 607-614. (ac.ir)
  • Acidic pH was the better condition for fluoride adsorption and the bicarbonate content cause higher pH values and thus diminished the affinity of the adsorption sites for fluoride. (ac.ir)
  • In terms of surface chemistry, protein adsorption is a critical phenomenon that describes the aggregation of these molecules on the exterior of a material. (wikipedia.org)
  • Brunauer, Emmett and Teller's model of multilayer adsorption is a random distribution of molecules on the material surface. (wikipedia.org)
  • Note 2: Adsorbed molecules are those that are resistant to washing with the same solvent medium in the case of adsorption from solutions. (wikipedia.org)
  • Adsorption is the capacity of a solid particle to attract molecules to its surface. (britannica.com)
  • In experiments where molecules are adsorbed on graphite, methanol is often used as a solvent for the larger molecules at target, and thus the adsorption properties of methanol affect the adsorption of the other molecule. (hindawi.com)
  • Gaining access to detailed adsorption data for methanol on graphite, such as positions and energetics like those provided here, is thus valuable both directly and as input data for larger simulations of molecules on graphite embedded in the (methanol) solvent. (hindawi.com)
  • Adsorption and binding of capping molecules for highly luminescent CdSe nanocrystals--DFT simulation studies. (mendeley.com)
  • These surfaces are typically used for the adsorption of hydrophobic molecules such as lipid-rich biomolecules. (thermofisher.com)
  • The broad spectrum of immune responses elicited coupled with the attendant benefits of safety suggest that spore adsorption could be appropriate for improving the immunogenicity of some vaccines as well as the delivery of biotherapeutic molecules. (ei-resource.org)
  • This flow is required to push out the oxygen that was captured in the previous adsorption phase of tower B. By releasing the pressure in tower B, the carbon molecular sieves lose their ability to hold the oxygen molecules. (atlascopco.com)
  • They will detach from the sieves and get carried away through the exhaust by the small nitrogen flow coming from tower A. By doing that the system makes room for new oxygen molecules to attach to the sieves in a next adsorption phase. (atlascopco.com)
  • The adsorption of molecules onto a surface is a necessary condition for any surface mediated chemical process. (collinsdictionary.com)
  • Adsorption is the binding of molecules or particles to a surface. (collinsdictionary.com)
  • Adsorption means adhesion of atoms or molecules. (proprofs.com)
  • Anderson, M. and Jeng, F., "Adsorption Modeling with ACM: ISS CDRA Simulation," SAE Technical Paper 2002-01-2345, 2002, https://doi.org/10.4271/2002-01-2345 . (sae.org)
  • A survey of recent progress in numerical simulation of nanomaterials, Adsorption and Transport at the Nanoscale explains the central role of molecular simulation in characterizing and designing novel materials and devices. (eurobuch.com)
  • In such a context, research in adsorption of gases by carbon nanomaterials has experienced considerable growth in recent years, with increasing interest for practical applications. (worldcat.org)
  • This book provides a selected overview of some of the most interesting scientific results regarding the outstanding properties of carbon nanomaterials for gas adsorption and of interest both for basic research and technological applications. (worldcat.org)
  • The exact nature of the bonding depends on the details of the species involved, but the adsorption process is generally classified as physisorption (characteristic of weak van der Waals forces ) or chemisorption (characteristic of covalent bonding). (wikipedia.org)
  • Hydrogen adsorption for the samples with added catalyst showed correlation with BET surface area, exhibited isotherms typical for physisorption and no features which could be assigned to spillover effect. (diva-portal.org)
  • During the last years, the authors have synthesized, characterized, and studied the adsorption properties of nitroprussides, Prussian blue analogues, akaganeites, MeAPOs, metal-organic frameworks, and extremely high specific surface amorphous silica, which allowed the storage of about 11 wt. (intechopen.com)
  • Here, we present data on the formation of silica-lysozyme composites through two different synthesis approaches (co-precipitation vs. adsorption) and show that the chemical and structural properties of these composites, when analyzed using a combination of synchrotron-based scattering (total scattering and small-angle X-ray scattering), spectroscopic, electron microscopy, and potentiometric methods vary dramatically. (frontiersin.org)
  • The general working principle of adsorption dryers is simple: moist air flows over hygroscopic material (typical materials used are silica gel, molecular sieves, activated alumina) and is thereby dried. (atlascopco.com)
  • Samples of high-silica SSZ-13, ion exchanged with protons and alkali-metal cations Li+, Na+, and K+ were investigated using adsorption isotherms of CO2 and N2. (biomedsearch.com)
  • To validate this approach, quantum theoretical calculations for the adsorption of glucose were performed: Equilibrium geometries were studied with density functional theory (DFT) and dispersion-corrected DFT, whereas the adsorption energies were calculated with two standard density functional approximations and five dispersion-containing DFT approaches. (warwick.ac.uk)
  • We investigate the adsorption of a single polymer of length N to a planar solid surface in the absence of hydrodynamic interactions. (uva.nl)
  • An effective method for removing dissolved organic substances that cause tastes, odours, or colours is adsorption by activated carbon. (britannica.com)
  • An adsorption apparatus and method of adsorption for treatment of wastewater is disclosed, and comprises an inlet for the wastewater connected to a metals trap which adsorbs metals and a second trap which filters organic materials from the wastewater, positioned between the inlet and the metals trap, wherein the second trap at least partially comprises either a phosphate or an activated carbon. (freepatentsonline.com)
  • 3. Adsorption of a trace gas component when another organic vapor component, or water vapor is already adsorbed Overall the results obtained from this research will help to answer the following two questions: For an activated carbon of known parameters: 1. (cdc.gov)
  • It provides practical guidance for the design of liquid- and vapor-phase devices for the adsorption of organic chemicals. (cpeo.org)
  • The need to develop technologies capable of achieving high removal efficiencies for mercury chloride emission control led many researchers to focus their attention on the evaluation of the adsorption capacity and selectivity shown by different solids. (nsti.org)
  • Twelve commercial lipase preparations were tested for selectivity in the adsorption of-lipase. (lu.se)
  • These data are then available as input to and/or for fine-tuning of molecular dynamics simulations of the methanol adsorption process. (hindawi.com)
  • Recent experimental studies indicate that the adsorption dynamics is dominated by non-equilibrium effects. (uva.nl)
  • Learn more about how QSense QCM-D can be used to characterize biomolecular adsorption dynamics and the amount adsorbed to the surface of interest. (biolinscientific.com)
  • To examine which mechanism (including π-π, hydrogen bond, vdW, and hydrophobic interactions) governed the adsorption capacity, the π-stacking ability, hydrogen bond interaction energy, polarizability, and interaction intensity of ACs with water were examined using molecular dynamics simulations and density functional theory calculations. (rsc.org)
  • Finally, the different interaction forces that make possible adsorption were discussed. (intechopen.com)
  • Activation thermodynamic parameters, such as activation enthalpy (Δ H *), activation entropy (Δ S *), activation Gibbs free energy (Δ G *) and activation energy (E), have been evaluated and the possible adsorption mechanism also was suggested. (scielo.cl)
  • The possible adsorption mechanism of the adsorption process also was suggested. (scielo.cl)
  • Most adsorption models can be applied successfully to explain single component adsorption at low concentrations. (cdc.gov)
  • The maximum hydrogen adsorption measured on doped MOF-5 was 0.43 wt. (diva-portal.org)
  • Hydrogen adsorption was measured for a set of Zn- and Co-based MOFs at near ambient temperatures. (diva-portal.org)
  • Hydrogen adsorption values in the studied MOFs correlated well with surface area and pore volume but did not exceed 0,75wt. (diva-portal.org)
  • In this thesis the effect of Pt catalyst addition on hydrogen adsorption in MOF-5 was not confirmed. (diva-portal.org)
  • Hydrophobic, GO-AC hydrogen bond, van der Waals, and electrostatic interactions may contribute to the adsorption of ACs on GO, but are not important in regulating the adsorption capacity. (rsc.org)
  • Pharmaceutical industry applications, which use adsorption as a means to prolong neurological exposure to specific drugs or parts thereof, [ citation needed ] are lesser known. (wikipedia.org)
  • The adsorption was not significantly influenced by pH changes in the adsorption buffer, indicating that hydrophobic and not electrostatic interactions are the dominating adsorption forces. (lu.se)
  • Adsorption of surfactant lipids by single-walled carbon nanotubes in mouse lung upon pharyngeal aspiration. (cdc.gov)
  • Simple mass transfer models were applied to the experimental data to examine the adsorption mechanism and it was found that both external mass transfer and intraparticle diffusion played important roles in the adsorption mechanisms. (environmental-expert.com)
  • The thermodynamic parameters suggested that the adsorption process was spontaneous and endothermic in nature. (springer.com)
  • However, there is an ongoing effort to improve the understanding of the adsorption mechanism on activated carbon, taking into account the many parameters, which influence this process. (cdc.gov)
  • The wave front behavior, i.e., its velocity, length, and shape, reflects the influences of all the variables governing the adsorption process in a packed bed reactor. (asce.org)
  • These two dynamic regimes are separated by an energy scale that is characterized by non-equilibrium contributions during the adsorption process. (uva.nl)
  • The CMS in tower A will get saturated, while tower B, due to the depressurization, will be able to restart the adsorption process. (atlascopco.com)
  • In this papere, adsorption properties of the nonionic surfactant Tergitol 15 S-7 on clays are presented. (epa.gov)
  • The presence of carbonate, for example, can cause skin irritation because of its alkaline nature, and iron oxides and hydroxides reduce the adsorption properties of clays. (ingentaconnect.com)
  • ten Brink, Karl C.. "Adsorption studies on clays. (rice.edu)
  • The magnitude of delay caused by adsorption, diffusion partitioning, preferential partitioning, and permeability variation were compared. (unt.edu)
  • Diffusion partitioning was shown to have a larger effect on tracer delay than adsorption while preferential partition was shown to have no effect. (unt.edu)
  • Tracer delay was shown to be approximated closely by known permeability variations even when adsorption and diffusion effects are ignored. (unt.edu)
  • Various methods to measure diffusivity, such as the Differential Adsorption Bed (DAB), the time lag, the diffusion cell, chromatography, and the batch adsorber methods are also covered by the book. (whsmith.co.uk)
  • Adsorption can be found in many applications and systems such as activated charcoal, heterogeneous catalysts, the use of waste heat to provide water that is cold for air conditioning,and synthetic resins. (proprofs.com)
  • to be exact, gas adsorption offers evidence concerning the mesopore area, volume and size of the pores together with the energetics of adsorption [ 2 ]. (intechopen.com)
  • We argue that in this regime the single chain adsorption is closely related to a field-driven polymer translocation through narrow pores. (uva.nl)
  • In particular, effects of the side-chain density of the bottlebrush polyelectrolyte, concentration, mixing ratio and molecular weigh of the linearpolyelectrolyte on formation, solution properties, stability and adsorption of PECs were addressed. (diva-portal.org)
  • Induc¬tively coupled plasma atomic emission spectrometry (ICP-AES) was used for determination of arsenic concentration after adsorption. (srce.hr)
  • Addi¬tionally, the influence of phosphate concentration on adsorption of model arsenic samples was examined and it was shown that (at least in examined range of arsenic and phosphate concentration) there is no sig¬nificant influence of phosphate on adsorption of arsenic. (srce.hr)
  • Many research groups are now producing or using such materials for gas adsorption, storage, purification, and sensing. (worldcat.org)
  • A novel quaternized-chitosan-modified reduced graphene oxide (HACC-RGO) combined the adsorption advantages of RGO and 2-Hydroxypropyltrimethyl ammonium chloride chitosan (HACC). (springer.com)
  • This paper provides a rational approach to design of packed bed adsorption reactors based upon materials balance principle, combined with kinetic modeling. (asce.org)