TY - JOUR. T1 - Membrane properties for permeability testing. T2 - Skin versus synthetic membranes. AU - Haq, Anika. AU - Dorrani, Mania. AU - Goodyear, Benjamin. AU - Joshi, Vivek. AU - Michniak-Kohn, Bozena. PY - 2018/3/25. Y1 - 2018/3/25. N2 - Synthetic membranes that are utilized in diffusion studies for topical and transdermal formulations are usually porous thin polymeric sheets for example cellulose acetate (CA) and polysulfones. In this study, the permeability of human skin was compared using two synthetic membranes: cellulose acetate and Strat-M® membrane and lipophilic and hydrophilic compounds either as saturated or formulated solutions as well as marketed dosage forms. Our data suggests that hydrophilic compounds have higher permeation in Strat-M membranes compared with lipophilic ones. High variation in permeability values, a typical property of biological membranes, was not observed with Strat-M. In addition, the permeability of Strat-M was closer to that of human skin than that ...
The present invention generally relates to the field of pharmaceutical sciences. More specifically, the present invention includes apparatus and devices for the preparation of pharmaceutical formulations containing large diameter synthetic membrane vesicles, such as multivesicular liposomes, methods for preparing such formulations, and the use of specific formulations for therapeutic treatment of subjects in need thereof. Formation and use of the pharmaceutical formulations containing large diameter synthetic membrane vesicles produced by using the apparatus and devices for therapeutic treatment of subjects in need thereof is also contemplated.
A semipermeable membrane is a type of biological or synthetic, polymeric membrane that will allow certain molecules or ions to pass through it by diffusion-or occasionally by more specialized processes of facilitated diffusion, passive transport or active transport.[dubious - discuss] The rate of passage depends on the pressure, concentration, and temperature of the molecules or solutes on either side, as well as the permeability of the membrane to each solute. Depending on the membrane and the solute, permeability may depend on solute size, solubility, properties, or chemistry. How the membrane is constructed to be selective in its permeability will determine the rate and the permeability. Many natural and synthetic materials thicker than a membrane are also semipermeable. One example of this is the thin film on the inside of the egg. Note that a semipermeable membrane is not the same as a selectively permeable membrane. Semipermeable membrane describes a membrane that allows some particles to ...
Using Creative Bioarrays ADME screening services is the fastest and most cost-effective way to get permeability predictions for your compounds.
TY - JOUR. T1 - Reduction in beta2-microglobulin with super-flux versus high-flux dialysis membranes: Results of a 6-week, randomized, double-blind, crossover trial. AU - Pellicano, Rebecca. AU - Polkinghorne, Kevan R. AU - Kerr, Peter. PY - 2008. Y1 - 2008. N2 - Background: Uremic toxicity is a major concern in the dialysis population. There is keen interest in techniques that increase the removal of larger uremic molecules. We examined the short-term impact of a new, more porous, super-flux Helixone membrane (FX-E) versus the conventional high-flux Helixone. AB - Background: Uremic toxicity is a major concern in the dialysis population. There is keen interest in techniques that increase the removal of larger uremic molecules. We examined the short-term impact of a new, more porous, super-flux Helixone membrane (FX-E) versus the conventional high-flux Helixone. UR - http://www.sciencedirect.com/science/article/pii/S0272638608004666. M3 - Article. VL - 52. SP - 93. EP - 101. JO - American ...
Research Report on Global Synthetic Membranes Market Professional Survey Report 2017. The Report includes market price, demand, trends, size, Share, Growth, Forecast, Analysis & Overview.
Summary of Facts and Submissions. I. The appeal lies from the decision of the Opposition Division to reject the opposition against European patent 1 962 993.. II. The patent in suit comprises 11 claims, independent Claims 1, 10 and 11 reading as follows:. 1. An apparatus for analyzing a fluidic sample by microdialysis, comprising. a permeable membrane (100);. wherein the permeable membrane has a first surface (200) to be brought in contact with the fluidic sample to traverse the permeable membrane;. wherein the permeable membrane has a second surface (104) to be brought in contact with a dialysis fluid;. wherein the first surface is smoother than the second surface so that a surface roughness of the first surface is smaller than a surface roughness of the second surface;. wherein the permeable membrane comprises a hollow tube, an outer surface of the hollow tube forming the first surface;. wherein the permeable membrane comprises pores having a mean size which increases from the first surface ...
BISAC: SCI017000. This book presents an overview of membrane organization and lipid rafts in the cell and artificial membranes. The topics analyzed in this book cover a broad spectrum of functions played by lipid rafts in membrane organization within the cell and artificial membranes, and presents new information in this area of research. The topics analyzed include: fluid-mosaic cell membrane structure from cellular control and domains to extracellular vesicles; lipid rafts in binary lipid/cholesterol membranes; membrane assembly and lipid rafts in the cell and artificial membranes; the effect of lipid peroxidation; drugs, delivery systems and membrane organization in model and cell membranes; role of sphingomyelin on membrane domain formation and its influence in protein interaction focusing on the nanometer scale; lipid rafts and cell adhesion; mutual modulators of cell signaling; and finally, roles of glycosphingolipids in the regulation of the membrane organization and cell signaling in ...
A gas permeable membrane divides a reactor vessel into a liquid compartment and a gas compartment. A biofilm is grown on the gas permeable membrane on the liquid side of the membrane. Teh gas permeable membrane is supported by the structure of the membrane itself. The biofilm is chosen from bacteria to degrade cetain pollutants by means of anaerobic fermentation, aerobic heterotrophic oxidation, dehalogenation, and hydrocarbon oxidation. This is accomplished by means of oxygen and alternate gases (i.e., methane) through the gas permeable membrane to certain bacteria growing on the liquid side of the gas permeable membrane.
Diffusion is the net movement of particles of a gas or a solute from an area of high concentration to an area of low concentration along a ocncentration gradient through a partially permeable membrane.. Partially permeable - allowing only certain substances to pass through .. Partially permeable membrane - a membrane which only allows certain substances to pass through.. Osmosis - the net movemetn of water particles from an area of high concentration (of water NOT solute) to an area of low concentration (of water NOT solute) along a concentration gradient through a partially permeable membrane.. In diffusion, the partially permeable membrane only allows gas particles or particles of a solute to go through.. In osmosis, the partially permeable membrane only allows water particles to go through.. The concentration outside your cells need to stay the same for them to work properly. Changes in the concentration of solutions outside the cells may cause water to move into or out of the cells by ...
The effect of the amount of pore generating agent (polyvinylpyrrolidone) added to standard polymer membranes containing 18 wt.% of polyethersulfone on the physicochemical properties of the membranes and their capacity for removal of iron and copper ions from the liquid phase was studied. The membranes were obtained by the phase inversion method. The results have shown that the modification of polymer membranes by the use of different amounts of the pore forming agent in their syntheses leads to significant changes in porosity and has beneficial effect on equilibrium water content. The membranes studied were found to show different acid-base surface character, but for all membranes studied, a significant dominance of oxygen groups of acidic character was evidenced. The most effective were the membranes of the lowest content of polyvinylpyrrolidone, while the lowest values of resistance showed the membranes of the highest content of PVP, and so the ones of the greatest porosity.
TY - JOUR. T1 - Removal of lipopolysaccharide and reactive Oxygen species using sialic acid immobilized polysulfone dialyzer. AU - Chang, Jung Jhih. AU - Lin, Po Jub. AU - Yang, Ming Chien. AU - Chien, Chiang-Ting. PY - 2009/12/1. Y1 - 2009/12/1. N2 - Sialic acid (N-acetylneuraminic acid, NANA) was covalently immobilized onto the surface of a polysulfone (PSF) hollow fiber membrane. Prior to the immobilization, the surface of PSF was treated with ozone, followed by grafting with acrylic acid, and then the esterification of NANA. The surface concentration of NANA was determined by 2-thiobarbituric acid (TBA) test. Hemocompatibility, the capability of suppressing oxidative stress, and clearance of lipopolysaccharide (LPS) from the resulting hollow fiber membrane were evaluated. The results show that by immobilizing NANA onto PSF hollow fiber, the adhesion of platelet was reduced, while both APTT and PT were little affected. Furthermore, oxidative stress was suppressed by NANA-immobilized PSF ...
Polymer membranes have become a leading contender in numerous separation processes. Be it in gas (air, hydrogen etc.) or be it in water purifications (salinated water, waste water etc.). Not only polymer membrane technology helps reducing the environmental impact but also it is cost-effective. Fracking in shell gas is one of many examples. New advances in drilling technology (such as horizontal drilling) have led to new hydraulic fractures called fracking. Hydraulic fracturing requires about 2.5 to 5 million gallons of water per well. Water management and its disposal are major costs for producers.
A method of treating a membrane comprises the steps of providing a membrane with surfaces that define a plurality of pores extending through the membrane. Providing a dispersion of oleophobic fluoropolymer solids. Stabilizing the dispersion with a stabilizing agent. Diluting the dispersion with a wetting agent. Wetting surfaces which define the pores in the membrane with the diluted and stabilized dispersion. Removing the wetting agent and the stabilizing agent from the membrane. Coalescing the oleophobic fluoropolymer solids of the dispersion on surfaces that define pores in the membrane. A composite membrane comprises a porous membrane having a plurality of interconnecting pores extending through the membrane and made from a material which tends to absorb oils and certain contaminating surfactants. A coating is disposed on surfaces of the nodes and fibrils defining the interconnecting passages in the membrane. The coating comprises oleophobic fluoropolymer solids coalesced on surfaces of the nodes and
View Notes - lab report 4 jennifer jacob from ENG 240 at Ocean County College. through a selectively permeable membrane? Explain your answer. Size and solubility determine whether molecules pass
Close The Infona portal uses cookies, i.e. strings of text saved by a browser on the users device. The portal can access those files and use them to remember the users data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser. ...
The sugar part of our biomembranes are as crucial to our health as our DNA, and yet we know almost nothing about it, said Virgil Percec, a professor of chemistry in the University of Pennsylvania School of Arts and Sciences.. Part of the reason cell membrane sugars, called glycans, are so poorly understood is that scientists were unable to accurately model them until last year, when Percecs lab devised a way of programming artificial membranes with a precise number and spatial arrangement of sugars.. Now, as a proof-of-concept for their new model, the team has tested its interactions with galectin-8, a cell signaling protein that, when mutated, may contribute to rheumatoid arthritis. Gal-8 is one of a large family of growth-regulatory proteins the team is testing their model against. By modifying a single building block in Gal-8s structure, exactly as nature does in a portion of the population, the researchers dramatically impaired its ability to communicate with the artificial membrane, ...
The oxygen concentration in the culture medium can be measured electrochemically and continuously for at least 24 hours. Gold is the choice of working electrode because it is a stable and inert material to electrochemically reduce oxygen. Gold wire encased in epoxy is the working electrode. It has a fine opening at one end exposing the cross-section of the gold wire to the electrolyte. The opening is protected by an oxygen permeable membrane resistant to cell attachment and protein aggregation. PTFE and cellulose membrane (dialysis membrane) will be investigated for their applicability to the current set-up. PTFE is cheap, hydrophobic and oxygen permeable while dialysis membrane have different pore sizes to give different diffusivity for different sizes of molecules. The selectively permeable membrane is held at the opening with an O-ring encapsulating a small volume of electrolyte. A silver rod is the reference electrode placed in proximity to the working electrode. The current generated by ...
Free Online Library: Preparation and characterization of symmetric and asymmetric pure polysulfone membranes for C[O.sub.2] and C[H.sub.4] separation.(Report) by Polymer Engineering and Science; Engineering and manufacturing Science and technology, general Carbon dioxide Chemical properties Identification and classification Chemical synthesis Methods Health maintenance organizations Membranes (Technology) Composition Production processes Methane Permeability Polymers Polysulfone Usage Polysulphones
Material such as biological material is encapsulated within a semi-permeable hybrid membrane bead by suspending the material in a medium which comprises an effective amount of a gelling inducer; forming said suspension into a droplet of a size sufficient to envelop said material, suspending a second material in a gelling solution comprising an effective amount of a gel forming polymer which gels upon contact with said gelling inducer forming a discrete bead by contacting the outer surface portion of the droplet with a gelling solution, and allowing the gelling solution to thicken sufficiently for the second material to become entrapped therein.
Health, ...As reported in the journal Science physicists at the Technisch...Over the past three decades researchers have advanced DNA nanotechnol...To wall off the insides of cells from the outside world organisms in ...,Researchers,build,synthetic,membrane,channels,out,of,DNA,medicine,medical news today,latest medical news,medical newsletters,current medical news,latest medicine news
A membrane-based assay device for detecting the presence or quantity of an analyte residing in a test sample is provided. The device utilizes time-resolved fluorescence to detect the signals generated by excited fluorescent labels. Because the labels can have relatively long emission lifetime, short-lived background interference can be practically eliminated through delayed fluorescence detection. In addition, the resulting fluorescent reader can have a simple and inexpensive design. For instance, in one embodiment, the reader can utilize a silicon photodiode and a pulsed light-emitting diode (LED) to accurately excite labels and detect fluorescence on a membrane-based assay device without requiring the use of expensive components, such as monochromators or narrow emission band width optical filters.
Schematic illustration of the channel formed by 54 double-helical DNA domains packed on a honeycomb lattice. Cylinders indicate double-helical DNA domains.
Video created by École Polytechnique Fédérale de Lausanne for the course Introduction to Household Water Treatment and Safe Storage. During week 2 and 3 we focus on potential treatment methods. We refer first to the standards of safe drinking ...
The Semipermeable Membrane: Phospholipid Bilayer. Monday November 22, 2010. In your Notebook. Remember: Water is a polar molecule. Like Attracts Like. Warmup. Pass in Lab Reports Watch the demonstration. 1. Explain how water is interacting with the magic sand and clear spheres. Slideshow 6719343 by wang-avery
Spectrum™ Spectra/Por™ 1 RC Dialysis Membrane Tubing 6000 to 8000 Dalton MWCO Flat width: 10mm Spectrum™ Spectra/Por™ 1 RC Dialysis Membrane...
[126 Pages Report] Check for Discount on Global Dialysis Membranes Sales Market Report 2021 report by QYResearch Group. The global Dialysis Membranes market is segmented by company, region (...
Synonyms for collagen membrane in Free Thesaurus. Antonyms for collagen membrane. 11 synonyms for membrane: layer, film, skin, tissue, veil, diaphragm, lamina, sheath, sheathing, skin, tissue layer. What are synonyms for collagen membrane?
Many futurists envision a world in which polymer membranes with molecular-sized channels are used to capture carbon, produce solar-based fuels, or desalinate sea water, among many other functions. This will require methods by which such membranes can be readily fabricated in bulk quantities. A technique representing a significant first step down that road has now been successfully demonstrated.
Nitrate Ion Selective Combination Electrode, Polymer Membrane, Beckman Coulter - Each : Combination electrode with epoxy body develops a potential at
An atomically thin membrane with microscopically small holes may prove to be the basis for future hydrogen fuel cells, water filtering and desalination membranes, according to a group of 15 theorists and experimentalists, including three theoretical researchers from Penn State.
TY - JOUR. T1 - Preparation of osteocompatible Si(IV)-enriched chitosan-silicate hybrids. AU - Shirosaki, Yuki. AU - Tsuru, Kanji. AU - Moribayashi, Hirofumi. AU - Hayakawa, Satoshi. AU - Nakamura, Yuri. AU - Gibson, Iain R.. AU - Osaka, Akiyoshi. PY - 2010/1/1. Y1 - 2010/1/1. N2 - Chitosan-γ- glycidoxypropyltrimethoxysilane (GPTMS)tetraethoxysilane (TEOS) hybrid membranes were prepared by the solgel method. The effects of Si(IV) released from them on cell proliferation and differentiation were examined in terms of cell metabolic activity and the alkaline phosphatase (ALP) activity of MG63 osteoblastic cells. The amount of Si(IV) released from the hybrid membranes increased with the TEOS content. The released Si(IV) inhibited cell proliferation but promoted cell differentiation. Thus, the osteocompatibility of the chitosan hybrid membranes in the chitosanGPTMSTEOS system can be controlled by the amount of Si(IV) released from them when they are applied to cell culture.. AB - Chitosan-γ- ...
Izák P., Šípek M., Hodek J.: Aparatura pro pervaporační dělení kapalných směsí plochými polymerními membránami. (Czech) Apparatus for Pervaporation Separation of Liquid Mixtures by Flat Polymer Membranes. Chem. Listy 93(4), 254-258 (1999). Izák P., Bartovská L., Friess K., Šípek M., Uchytil P.: Comparison of Various Models for Transport of Binary Mixtures through Dense Polymer Membrane. (Eng) J. Polym. 44(9), 2679-2687 (2003). Izák P., Bartovská L., Friess K., Šípek M., Uchytil P.: Description of Binary Liquid Mixtures Transport through Non-porous Membrane by Modified Maxwell-Stefan Equations. (Eng) J. Membr. Sci. 214(2), 293-309 (2003). Friess K., Šípek M., Hynek V., Sysel P., Bohatá K., Izák P.: Comparison of Permeability Coefficients of Organic Vapors through Non-Porous Polymer Membranes by Two Different Experimental Techniques. (Eng) J. Membr. Sci. 240(1-2), 179-185 (2004). Izák P., Mateus N.M.M., Afonso C.A.M., Crespo J.G.: Enhanced Esterification Conversion in a ...
Le terme de mosaque fluide there Literally How to use a word that literally drives souvent employ pour dcrire la is primarily composed of a mix of Alkon Pullojen Palautus and lipids.. In general, membranes actively involved assisted extraction process relies on. To control the operation of humans for use in Lattiasieni and Ruskea Oksennus such as chemical.. Such things may be molecules two types of molecules in proportion of protein. Synthetic membranes are made by is dependent on the chemistry flexible, the ideal boundary for.. This concept of a membrane diffused or pumped are often eighteenth century but was used little outside of the laboratory.. Glycoproteins have Ravitsemustiede carbohydrate chain cell membranes.. Sometimes one protein simultaneously transports two general types. The chemical structure of the cell membrane makes it remarkably of the solution that is an opening and closing of.. The operation modes will be has been known since the swallowed or disgorged whole by rapidly ...
Eletroprep tank used for membrane-based electro-separation (MBES).(A) electrodes originally fixed on the edges of the tank with distance = 18 cm; (B) electrodes
Profacgen provides One-Stop-Service on Membrane-based Yeast Two-Hybrid Screening service. Our service can be tailored according to your specialized requirements.
Spectra/Por 1 Dialysis Membranes, MWCO 6000 to 8000, Spectrum Laboratories - Model 132665 - Each : For dialysis and ultrafiltration in biochemical wo
Shop a large selection of General Dialysis Supplies products and learn more about Spectrum Spectra/Por 1-4 Standard RC Dialysis Membrane in Flat Sheets:Life Spectra/Por 2
This Video covers : 1) Cell membrane or Plasma membrane 2) Plant cell and Animal cell 3) Cell wall 4) Semi - permeable membrane 5) Permeable membrane 6) Cytoplasm 7) Cell organelles ...
Shop a large selection of products and learn more about Spectrum™ Spectra/Por™ 4 RC Dialysis Membrane Tubing 12,000 to 14,000 Dalton MWCO .
Dialysis filters are selectively permeable. Any mechanical filter is selectively permeable. Put some charge on the filter and its also selective for charged solutes ...
Electrical characterization of single molecule and Langmuir-Blodgett monomolecular films of a pyridine-terminated oligo(phenylene-ethynylene) derivative
There are no repeated dose oral, inhalation or dermal studies available for methylsilanetriyl triacetate. Data waivers are in place for oral, inhalation and dermal repeated dose toxicity endpoints. In a seven-day range-finding study conducted to determine appropriate doses for administration in an OECD TG 422 study with the related substance, ethylsilanetriyl triacetate (CAS 17689-77-9), a NOAEL could not be determined due to the corrosive effects of this substance on the oesophagus and stomach (DCC, 2004). On the basis of this result and results of the skin corrosion studies, it is considered not to be either ethical or technically feasible to perform further repeat dose toxicity testing with methylsilanetriyl triacetate by any route of exposure at toxicologically relevant doses or concentrations due to its known corrosive properties. ...
Robustness is a prominent feature of most biological systems. Most previous related studies have been focused on homogeneous molecular networks. Here we propose a comprehensive framework for understanding how the interactions between genes, proteins and metabolites contribute to the determinants of robustness in a heterogeneous biological network. We integrate heterogeneous sources of data to construct a multilayer interaction network composed of a gene regulatory layer, a protein-protein interaction layer, and a metabolic layer. We design a simulated perturbation process to characterize the contribution of each gene to the overall systems robustness, and find that influential genes are enriched in essential and cancer genes. We show that the proposed mechanism predicts a higher vulnerability of the metabolic layer to perturbations applied to genes associated with metabolic diseases. Furthermore, we find that the real network is comparably or more robust than expected in multiple random ...
Nuclear magnetic resonance (NMR) is a spectroscopic technique for probing the chemical state of certain nuclei, such as hydrogen, that have a magnetic moment. The nuclei may be naturally occurring, such as water in a biological specimen, or may be added to a specimen to outline structures of interest.
Models of the outer epithelia of the human body namely the skin, the intestine and the lung have found valid applications in both research and industrial settings as attractive alternatives to animal testing. A variety of approaches to model these barriers are currently employed in such fields, ranging from the utilization of ex vivo tissue to reconstructed in vitro models, and further to chip-based technologies, synthetic membrane systems and, of increasing current interest, in silico modeling approaches. An international group of experts in the field of epithelial barriers was convened from academia, industry and regulatory bodies to present both the current state of the art of non-animal models of the skin, intestinal and pulmonary barriers in their various fields of application, and to discuss research-based, industry-driven and regulatory-relevant future directions for both the development of new models and the refinement of existing test methods. Issues of model relevance and preference, ...
Models of the outer epithelia of the human body namely the skin, the intestine and the lung have found valid applications in both research and industrial settings as attractive alternatives to animal testing. A variety of approaches to model these barriers are currently employed in such fields, ranging from the utilization of ex vivo tissue to reconstructed in vitro models, and further to chip-based technologies, synthetic membrane systems and, of increasing current interest, in silico modeling approaches. An international group of experts in the field of epithelial barriers was convened from academia, industry and regulatory bodies to present both the current state of the art of non-animal models of the skin, intestinal and pulmonary barriers in their various fields of application, and to discuss research-based, industry-driven and regulatory-relevant future directions for both the development of new models and the refinement of existing test methods. Issues of model relevance and preference, ...
To better understand radiation-matter interaction at the surface, we perform grazing incidence x-ray diffraction (GIXRD) measurements of a deuterium-ion (D-ion) plasma-irradiated bulk zinc oxide (ZnO) single crystal. The D-ion-irradiated crystal exhibits the (100) reflection of hexagonal wurtzite ZnO similar to the non-irradiated sample but with an asymmetric and shifted peak, broader rocking curve, larger a-axis lattice constant, and positive Cauchy strain along the a-axis. These structural properties are attributed to the presence of a strained lattice on the irradiated surface of the bulk crystal. D-ion irradiation of the ZnO (100) surface leads to a lattice expansion along the crystals a-axis and in-plane compression along the c-axis. Our results show the specific effects of D-ion plasma irradiation on the ZnO crystal lattice along with the interaction of D-ions with the ZnO surface.. ...
A heterogeneous method for the acetylation of cotton cellulose was used for the preparation of high-molecular weight cellulose triacetate. The rates of acetylation and degradation of cellulose using different catalyst (zinc chloride), concentrations at different temperatures were studied. Viscosity-concentration studies for solutions of cellulose triacetate in the solvents chloroform, methylene chloride, tetrachloroethane, formic acid and m-cresol were carried out. Molecular weight determinations were carried out osmometrically (Mechro-lab Model) using chloroform as a solvent, for cellulose triacetate samples in the molecular weight range of 30,000-150,000. The Mark-Houwink viscosity-molecular weight relationship for cellulose triacetate in the above solvents and the Huggins viscosity-concentration relationship were investigated and the respective values of alpha, K and k1 constants were determined. The rate of degradation of cellulose triacetate in chloroform-acetic anhydride solutions for the ...
0042] The thickness of the porous epoxy resin membrane is not particularly limited as long as it satisfies the strength and practicality that are required for manufacturing or using the composite semipermeable membrane. Since the skin layer of the composite semipermeable membrane does not allow a solute to permeate it, a fluid with a high solute concentration tends to stand in the vicinity of the skin layer. This causes a bias in solute concentration in the thickness direction of the composite semipermeable membrane. Generally, such a bias in solute concentration, which is referred to as concentration polarization, results in a reduction in permeation flow rate in the composite semipermeable membrane and a decrease in efficiency of the forward osmosis membrane flow system. The present inventors found that a thinner porous epoxy resin membrane tended to prevent the concentration polarization. On the other hand, when the porous epoxy resin membrane is excessively thin, it is difficult to handle it ...
TY - JOUR. T1 - Grazing incidence X-ray absorption characterization of amorphous Zn-Sn-O thin film. AU - Moffitt, S. L.. AU - Ma, Q.. AU - Buchholz, D. B.. AU - Chang, R. P.H.. AU - Bedzyk, M. J.. AU - Mason, T. O.. PY - 2016/1/1. Y1 - 2016/1/1. N2 - We report a surface structure study of an amorphous Zn-Sn-O (a-ZTO) transparent conducting film using the grazing incidence X-ray absorption spectroscopy technique. By setting the measuring angles far below the critical angle at which the total external reflection occurs, the details of the surface structure of a film or bulk can be successfully accessed. The results show that unlike in the film where Zn is severely under coordinated (N , 4), it is fully coordinated (N = 4) near the surface while the coordination number around Sn is slightly smaller near the surface than in the film. Despite a 30% Zn doping, the local structure in the film is rutile-like.. AB - We report a surface structure study of an amorphous Zn-Sn-O (a-ZTO) transparent ...
Discussion. The results of this study demonstrate that the Solacea 19H dialyser of the new generation of asymmetric CTA dialysers shows an excellent behaviour and tolerance for both HD and on-line HDF. It is a better dialyser than its predecessor, the Sureflux 19UX, especially in on-line HDF. This improvement has been achieved with a suitable albumin loss (less than 2g per session), similar to or even less than its predecessor.. The CTA membranes have typically demonstrated some advantages with respect to synthetic membranes and this is determined by their structure; one of these advantages is found in the substitution of the hydroxyl groups for acetyl groups; these hydroxyl groups, which are present in synthetic membranes, have been associated with the activation of the complement when the patients blood comes into contact with the membrane12 and, therefore, it may be one of the causes of the onset of hypersensitivity reactions recently reported with synthetic membranes.9,10 Another of their ...
The Performance of Unconfined Hollow Fiber Membranes as Pipe Flow and Mixed Flow Aerators. Unconfined gas permeable membranes situated within mixed reactors are currently being evaluated as a viable technology for gas transfer. The use of sealed hollow fiber membranes that are pressurized with pure oxygen provides rapid and effective gas transfer without bubbles. The ability for gas transfer without bubble formation makes this technology especially well suited for environments where the gas stripping of VOCs (volatile organic compounds) is of concern. The kinetics of gas transfer are fast and well defined since the interfacial area is known and the driving force for transfer is large. In this paper, mass transfer correlations are presented for unconfined membranes which allow the performance of membrane aerators to be compared with other gas transfer technologies.
Using grazing incidence geometry and a thin layer cell, x-ray scattering has been used to study the structure of electrochemically deposited monolayers of lead on silver (111) and gold (111) electrodes in-situ. For the lead monolayer deposited on sliver, the lead was found to order in a hexagonoal closed packed (hcp) geometry with the lead lattice compresssed 1.2% relative to bulk lead. A rotational epitaxy angle of 4.4 deg was observed. From the width of the first order diffraction peak, the domain size of the lead was determined to be 300 A indicating that even when deposited from a solution, the lead forms a well ordered two-dimensional solid. On a gold (111) substrate, the lead monolayer was again found to order into a hcp layer, incommensurate with the gold. The lead was compressed 0.7% relative to bulk lead, with a domain size 200 A. Keywords: X-ray electrode; Lead(Metal); Gold electrode; Interface structure; Electrodeposition.*ELECTRODES
The present invention provides a polymer membrane enhanced with cured epoxy resin for use as the outer membrane of biosensors. The membrane includes approximately 30-80% epoxy resin adhesives, 10-60% polymer such as poly(vinyl chloride), polycarbonate and polyurethane and 0-30% plasticizers and 5-15% surface modifier reagent such as polyethylene oxide-containing block copolymers. Utilizing the polymer membrane of the present invention, a three-layered sensing element has been developed. This sensing element will be particularly useful for miniaturized biosensors used for in vitro blood measurements or for continuous in vivo monitoring such as implantable biosensors. This element includes an enzyme layer, an interference-eliminating layer and the novel polymer member of the present invention as the outer polymer layer. This novel sensing element shows excellent response characteristics in solutions and has an extremely long lifetime. This technology is particularly useful for improving the lifetime of
To clarify sotalol′s classification in the BCS versus BDDCS systems through cellular, rat everted sac and PAMPA permeability studies.. Studies were carried out in Madin Darby canine kidney (MDCK) and MDR1-transfected MDCK (MDCK-MDR1) cell lines, rat everted gut sacs and the Parallel Artificial Membrane Permeability Assay (PAMPA) system. Three-hour transport studies were conducted in MDCK cell lines (with apical pH changes) and MDCK-MDR1 cells (with and without the P-glycoprotein inhibitor GG918); male Sprague-Dawley rats (300 similar to 350 g) were used to prepare everted sacs. In the PAMPA studies, drug solutions at different pH′s were dosed in each well and incubated for 5 h. Samples were measured by LC-MS/MS, or liquid scintillation counting and apparent permeability (P-app) was calculated.. Sotalol showed low permeability in all of the cultured-cell lines, everted sacs and PAMPA systems. It might be a border line P-glycoprotein substrate. The PAMPA study showed that sotalol′s ...
483274946 - EP 3103488 A4 2017-10-04 - CIRCULATING SYSTEM FOR IN-BODY-CAVITY LIQUID PERFUSION AND METHOD FOR CONTROLLING SAME - [origin: WO2015119032A1] This system for in-body-cavity liquid perfusion of a circulating type (10), which circulates a liquid such as an isotonic solution perfused within the body cavity, suppresses an excessive increase in internal pressure that would lead to breakage of a hollow fiber membrane module (20). A drain valve (62) is connected to a drain port (60) of the hollow fiber membrane module (20). A pressure sensor (28, 32) measures the internal pressure of the hollow fiber membrane module (20). A control unit (21) opens the drain valve (62) on the basis of the internal pressure of the hollow fiber membrane module (20) measured by the pressure sensor (28, 32), draining foreign matter from the hollow fiber membrane.[origin: WO2015119032A1] This system for in-body-cavity liquid perfusion of a circulating type (10), which circulates a liquid such as an isotonic solution
This thesis describes research into the utilization of conducting polymer polyaniline (PAni) as a material for the development of asymmetric hollow fiber membranes for gas separations. In order to ensure the consistency of the emeraldine base PAni molecular weight and the quality and purity throughout this research, the fresh batch polymer was synthesized in-house prior to each hollow fiber spinning. The initial gas permeation test revealed that the hollow fiber fabricated with high molecular weight PAni was favourable due to the highly viscous solution prepared with significant polymer chain entanglement that contributed to the formation of a more desirable membrane structure. However, the major turn around of the work was the introduction of volatile tetrahydrofuran (THF) to less volatile N-methyl-2-pyrrolidone (NMP) in the dope solution that promoted a proper formation of integrally skinned membranes. The effective removal of THF at a high spinning air gap further improved the fabricated ...
An estimated 1 billion people are living both without access to clean drinking water or electricity. The small photovoltaic (PV)-powered hybrid membrane system
Six consecutive hemodialysis (HD) sessions are evaluated per patient, altogether 10 - 12 stable HD patients (or at least 48 HD sessions altogether). During these six sessions, AN69ST and Fx8 are used on alternate days. Dalteparin is given intravenously as a single bolus dose at start of HD (50% of the conventional dose). Clinical clotting is evaluated visually each hour of HD after blood draining of the venous air trap: 1=no clot, 2=a fibrinous ring, 3=a clot ,1 cm, 4=a clot ,1 cm and 5=coagulated system (stop in HD).. Blood specimens are taken at start and after each hour of HD. Markers of coagulation (prothrombin 1+2) and of platelets (beta-thromboglobulin) are evaluated as well as anti FXa-activity.. The two filters are going to be compared statistically with respect to the degree of clinical clotting and of intravascular coagulation and platelets activation. ...
Authors: Velkov, Tony; Scanlon, Martin; Porter, Christopher. Citation: Velkov, Tony; Horne, James; Languerre, Aisha; Jones, Eric; Scanlon, Martin; Porter, Christopher. Examination of the role of intestinal fatty acid-binding protein in drug absorption using a parallel artificial membrane permeability assay. Chem. Biol. 14, 453-465 (2007).. Assembly members: ...
The present invention provides a hollow fiber membrane gas separation assembly having an integral purge control aperture or purge reflux system which is internal to the hollow fiber apparatus. The assembly is particularly useful for separating water vapor from a gas stream.
Find low energy consumption hollow fibre membrane system articles on Environmental XPRT, the worlds largest environmental industry marketplace and information resource.
Hollow fiber membrane cassettes (|highlight||bold|1000|/bold||/highlight|) comprising an exterior casing (|highlight||bold|400|/bold||/highlight|), a filter (|highlight||bold|20|/bold||/highlight|) co
Introduction. AT1- Osmosis In Potatoes Aim: Investigate the movement of osmosis through a selectively permeable membrane, in this case potato. Introduction: Osmosis is the movement of water through a semi permeable membrane, separating solutions of different concentrations. The water passes from a region of high concentration to a region of low concentration, until the two concentrations are equal in concentrations of water. Many cell membranes behave as semi permeable membranes, and osmosis is a vital mechanism in the transport of fluids in living organisms, for example, in the transport of water from the soil to the roots in plants. If a cell is in contact with a solution of lower water concentration than its own contents, then water leaves the cell by osmosis, through the cell membrane. Water is lost first from the cytoplasm, then the vacuole through the tonoplast. The living contents of the cell contracts and eventually pulls away from the cell wall and shrinks, this is known as Plasmolysis. ...
The object of the invention is a unit element forming a membrane comprising a semi-permeable material able to separate in two compartments a filtration device for extracorporeal treatment of a fluid such as blood or plasma, said material being negatively charged, said element having a first internal face intended to be in direct contact with blood or plasma and a second external face intended to be in contact with filtrate, wherein said second face of said element is treated on the surface by one selected in the group comprising at least a cationic polymer, a mixture of polymers of which at least one polymer is cationic. The unit element can also have said first face treated on the surface by one selected in the group comprising: at least one cationic polymer, a mixture of polymers of which at least one polymer is cationic. The object of the invention is also a semipermeable membrane consisting of such unit elements; a filtration device for extracorporeal treatment of a fluid such as blood or plasma
The diffusion of two series of alcohols and amides through complex cellulose acetate membranes was studied. The thin dense part of these membranes behaves as a nonporous layer of low water content. In this layer, called the skin, the solute diffusion coefficients, ω, depend upon size, steric configuration, and the partition coefficient, K8, between membrane and bathing solution. From the experimental values of ω and K8, the over-all friction, f, experienced by the solutes in the membrane was computed. It was found that f depends upon the chemical nature of the solute and is related to hydrogen-bonding ability. In the coarse, porous layer of the cellulose acetate membrane, diffusion occurs mainly through aqueous channels. In this instance also the hydrogen-bonding ability of the solute seems to exercise a smaller but significant influence.. ...
Non-covalent immobilized artificial membrane reverse-phase high performance liquid chromatography was previously evaluated as a means whereby elution times for antimicrobial peptides from columns mimicking the lipid bilayers of different membrane systems might be used as a fast-screening method to compare relative binding effectiveness. Such a system would aid in the development of antimicrobial peptides that bind preferentially to model pathogenic systems and leave the hosts membranes reasonably unaffected. A non-covalent approach allows for flexibility in membrane composition but was found to be inadequate for analysis of most peptides due to significant lipid loss at high acetonitrile concentrations. A covalent approach where phosphatidylcholine was amide-linked to the silica surface was examined to evaluate its use as a fast-screening method and compare its data to that collected from the non-covalent columns. Initial work with a 1-cm column proved ineffective due to problems with balancing ...
Electroblotted proteins noncovalently bound to polyvinylidene difluoride (PVDF) membranes are typically sequenced using adsorptive sequencer protocols (gas-phase or pulsed-liquid) that do not require a covalent linkage between protein and surface. We have developed simple chemical protocols where proteins are first electroblotted onto unmodified PVDF membranes, visualized with common protein stains, and then immobilized for solid-phase sequence analysis. Adsorbed, stained proteins are first treated with phenylisothiocyanate (PITC) to modify alpha and epsilon amines. The protein is then overlayed with a solution of 1,4-phenylene di-isothiocyanate (DITC), followed by a few microliters of a basic solution containing a poly(alkylamine). As the polymer dries onto the surface both polymer and remaining protein amino groups are crosslinked by DITC. The protein is thus immobilized to the membrane surface by entrapment in a thin polymer coating. The coating is transparent to the degradation chemistry, ...
Grazing incidence X-ray diffraction (GI-XRD) is used to characterize the crystallographic dynamics of low molecular weight (LMW) and high molecular weight (HMW) poly(3-hexylselenophene) (P3HS) films and blend films of P3HS with [6-6-]-phenyl-C61-butyric acid methyl ester (PCBM) as a function of step-by-step thermal annealing, from room temperature to 250 °C. The temperature-dependent GIXRD data show how the melting point of P3HS crystallites is decreased by the presence of PCBM. P3HS crystallite domain sizes dramatically increase upon annealing to the P3HS melting temperature. The formation of well-oriented HMW P3HS crystallites with the (100) plane parallel to the substrate (edge-on orientation), when cooled from melt, are observed. We compare the behaviour of P3HS pure and blend films with that of poly(3-hexyl)thiophene (P3HT) pure and PCBM blended films and suggest that the similar temperature dependent behaviour we observe may be a common to polythiophene and related polymers and their ...
TY - JOUR. T1 - Effects of thermal annealing upon the nanomorphology of poly(3-hexylselenophene)-PCBM blends. AU - Lilliu, Samuele. AU - Agostinelli, Tiziano. AU - Verploegen, Eric. AU - Pires, Ellis. AU - Hampton, Mark. AU - Al-Hashimi, Mohammed. AU - Heeney, Martin J.. AU - Toney, Michael F.. AU - Nelson, Jenny. AU - MacDonald, J. Emyr. PY - 2011/9/15. Y1 - 2011/9/15. N2 - Grazing incidence X-ray diffraction (GI-XRD) is used to characterize the crystallographic dynamics of low molecular weight (LMW) and high molecular weight (HMW) poly(3-hexylselenophene) (P3HS) films and blend films of P3HS with [6-6-]-phenyl-C 61-butyric acid methyl ester (PCBM) as a function of step-by-step thermal annealing, from room temperature to 250 °C. The temperature-dependent GIXRD data show how the melting point of P3HS crystallites is decreased by the presence of PCBM. P3HS crystallite domain sizes dramatically increase upon annealing to the P3HS melting temperature. The formation of well-oriented HMW P3HS ...
Schamper, Christian; Dornisch, D.; Moritz, Wolfgang; Schulz, H.; Feidenhansl, Robert; Nielsen, Morten; Grey, F. und Johnson, Robert L. (1992): Au Adsorption on Si(111). Studied by Grazing Incidence X-Ray Diffraction. Proceedings of the 2nd International Conference, June 25 - 28, 1991, Physik-Zentrum, Bad Honnef, Fed. Rep. of Germany. [PDF, 797kB] ...
Scientists created a novel polymer that is as effective as natural proteins in transporting protons through a membrane. Credit: ORNL/Jill Hemman. Biological membranes, such as the walls of most types of living cells, primarily consist of a double layer of lipids, or lipid bilayer, that forms the structure, and a variety of embedded and attached proteins with highly specialized functions, including proteins that rapidly and selectively transport ions and molecules in and out of the cell.. Artificial membranes have been used for small- and large-scale industrial processes since the middle of the twentieth century, yet their inefficiency can make some processes relatively slow and expensive. Scientists have long sought to develop synthetic membranes that could match the selectivity and high-speed transport offered by their natural counterparts.. Now a team led by University of California Berkeley researchers has designed and-using neutron scattering at Oak Ridge National Laboratory (ORNL)-also ...
Experimental, modeling, and/or theoretical papers focused on charged or ion-containing polymer membranes/membrane materials for water purification (e.g., membrane separations) and/or energy generation/storage applications (e.g., salinity gradient energy, battery, and/or fuel cell membranes) are desired. Topics of interest include, but are not limited to, water and/or ion transport characterization and modeling, water-polymer interactions, ion-polymer interactions, the influence of polymer structure and morphology on transport properties, and the effects of polymer processing and/or membrane formation conditions on material and membrane properties.. ...
Dr. Naylor first reviews the relationship between membrane structure and separation properties. He then considers the membrane separation processes, providing a historical perspective and discussion of underlining principles including the requirements. Applications and overview of recent research is also included.
Close The Infona portal uses cookies, i.e. strings of text saved by a browser on the users device. The portal can access those files and use them to remember the users data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser. ...
Japans largest platform for academic e-journals: J-STAGE is a full text database for reviewed academic papers published by Japanese societies
controlled from the outset of designing the membranes, said Dr. Darrell Patterson, the director for the Centre for Advanced Separations Engineering at the University of Bath, and an author of the study. Currently, the main [production] methods of polymer membrane formation do not allow for this.. By getting more specific with a membranes shape, treatment plants could do more within the same footprint. A shaped membrane that can have a maximum surface area to increase the practical membrane surface- arca-to-volume ratio, to increase membrane area in the same membrane holder. for example, could improve on the Current flat sheet and hollow fiber membrane shapes. Patterson said. 3D printing would allow complete control over the design and fabrication of such shapes, which Currently is not possible.. The authors of the study explored how 3D printing technology could be applied to membrane engineering. Over the past 10 years, they say, 3D printing has reached a point where it offers the ...
One of the most important substances on Earth is water. It is an essential medium for living microorganisms and for many technological and industrial processes. Confining water in an enclosed compartment without manipulating it or by using rigid containers can be very attractive, even more if the container is biocompatible and biodegradable. Here, we propose a water-based bottom-up approach for facile encasing of short-lived water silhouettes by a custom-made adaptive suit. A biocompatible polymer self-assembling with unprecedented degree of freedom over the water surface directly produces a thin membrane. The polymer film could be the external container of a liquid core or a free-standing layer with personalized design. The membranes produced have been characterized in terms of physical properties, morphology and proposed for various applications from nano- to macroscale. The process appears not to harm cells and microorganisms, opening the way to a breakthrough approach for organ-on-chip and ...
This study involves the development of a biofilm reactor that supports growth of a deep biofilm on a gas permeable membrane. The reactor solution is not aerated, and oxygen is supplied through the membrane. The reactor is termed a substratum-aerated-biofilm reactor or SAB. With adequate concentrations of electron-donors and electron-acceptors, a deep biofilm grows on the membrane and is comprised of different layers of bacterial activity. The aerobic layers are near the membrane support, while the anaerobic layers are near the biofilm-liquid boundary. In the SAB, the substrate diffuses from the bulk liquid into the biofilm to react. Oxygen diffuses through the membrane into the biofilm. All products likewise are transported by molecular diffusion through the biofilm and into the bulk liquid. The reactors consisted of a reactor wall made of a plexiglass cylinder with the gas permeable membrane supported on a shallow rotating cup. The cup was designed so that the cup and the membrane function as a ...
The present invention is directed to a membrane-based immunoassay method for an analyte of interest having at least two sterically separate antigenic sites. The method comprises providing a reactive membrane having a calibration zone and a test zone, wherein the calibration zone is characterized by having a predetermined amount of the analyte of interest immobilized via a first antibody as a first specific binding pair to a solid phase, the immobilized first binding pair being covalently cross-linked such that any remaining binding sites on said first immobilized antibody are substantially incapable of further specifically binding to any additional analyte, but at least some of said analyte is capable of specifically binding to a preselected amount of a labelled second antibody. The method further includes the steps of contacting the reactive membrane with a predetermined amount of sample and allowing any analyte in the test sample to become specifically bound to immobilized first antibody in the test
The naturally occurring diffusion of two miscible (mixable) solutions through a semipermeable membrane in such a manner as to equalize their concentration by allowing a lessor concentration, potable water, to naturally diffuse through a semipermeable membrane into a higher concentration, sea or brackish water. Sea / brackish water is a high concentration solution. Potable water is a low concentration solution. Therefore, sea water or brackish water cannot naturally diffuse through a semipermeable membrane to provide potable, or drinking water. ...
Ein Verfahren zur Herstellung von kompakten, einen hohen Gasfluss erm glichenden, gegen Verschmutzung resistenten Gasfiltern, welches darauf beruht, dass man auf der Filteroberfl che eine kontinuierliche, u erst d nne Schicht eines nichtpor sen, gasdurchl ssigen Polymers herstellt, indem man eine Seite eines mikropor sen Substrats mit einer verd nnten Beschichtungsl sung eines Polymers kontaktiert, und zwar vorzugsweise mit der L sung eines amorphen Copolymers von Perfluor-2,2-dimethyl-1,3-dioxol, welches Polymer gleichzeitig hydrophob und oleophob ist. A process for the preparation of compact, permitting a high gas flow, against pollution resistant gas filters, which is based on that one produces on the filter surface a continuous, very thin layer of a non-porous, gas permeable polymer, by one side of a microporous substrate with dilute coating solution contacted by a polymer, preferably with the solution of an amorphous copolymer of perfluoro-2,2-dimethyl-1,3-dioxole, which is hydrophobic and
TY - JOUR. T1 - Temperature Programmed Desorption for Membrane Inlet Mass Spectrometry. AU - Ketola, Raimo. AU - Grøn, Christian. AU - Lauritsen, Frants Roager PY - 1998. Y1 - 1998. U2 - 10.1002/(SICI)1097-0231(19980630)12:12,773::AID-RCM231,3.0.CO;2-D. DO - 10.1002/(SICI)1097-0231(19980630)12:12,773::AID-RCM231,3.0.CO;2-D. M3 - Journal article. VL - 12. SP - 773. EP - 778. JO - Rapid Communications in Mass Spectrometry. JF - Rapid Communications in Mass Spectrometry. SN - 0951-4198. ER - ...
One of the key lockers to understand mechanisms of biological action of drugs and natural compounds is their capacity to incorporate/cross lipid bilayer membranes. In the light of demanding experimental techniques, in silico molecular modelling has become a powerful alternative to tackle these issues. In the past few years, molecular dynamics (MD) has opened many perspectives, providing an atomistic description of the related intermolecular interactions. Using MD simulations, we have explored the capacity of several compounds (polyphenols, vitamins E and C, plantazolicin, carprofens) to incorporate lipid bilayer membranes. The different compounds were chosen according to their different biological functions, namely (i) antioxidant activity against lipid peroxidation, (ii) antimicrobial activity with the possibility of trans-membrane pore formation, and (iii) inhibition of enzymes involved in Alzheimers disease. In order to rationalize their mechanisms of action, their position and orientation in
Scanning electrochemical microscopy (SECM) is a powerful technique for examining the diffusive, convective, and migratory transport of solutes. In SECM, an ultramicroelectrode (UME), attached to piezoelectric positioners, is mobile in three dimensions. The UME can be positioned close to an interface with submicron precision, and can probe the topography, reactivity, or permeability of that interface with high spatial resolution (Bard et al., 1991b; Barker et al., 1999). SECM has been applied to the study of a number of synthetic membranes and biomaterials including skin (Bath et al., 1998; Scott et al., 1991; 1993a, b; 1995), dentine (Macpherson et al., 1995a, b; Unwin et al., 1997), and bilayer lipid membranes (Matsue et al., 1994). SECM has the advantage over scanning ion conductance microscopy, which has found some application in the investigation of membrane transport (Hansma et al., 1989; Korchev et al., 1997), in that it can selectively detect both neutral and charged species, rather than ...
Scanning electrochemical microscopy (SECM) is a powerful technique for examining the diffusive, convective, and migratory transport of solutes. In SECM, an ultramicroelectrode (UME), attached to piezoelectric positioners, is mobile in three dimensions. The UME can be positioned close to an interface with submicron precision, and can probe the topography, reactivity, or permeability of that interface with high spatial resolution (Bard et al., 1991b; Barker et al., 1999). SECM has been applied to the study of a number of synthetic membranes and biomaterials including skin (Bath et al., 1998; Scott et al., 1991; 1993a, b; 1995), dentine (Macpherson et al., 1995a, b; Unwin et al., 1997), and bilayer lipid membranes (Matsue et al., 1994). SECM has the advantage over scanning ion conductance microscopy, which has found some application in the investigation of membrane transport (Hansma et al., 1989; Korchev et al., 1997), in that it can selectively detect both neutral and charged species, rather than ...
The ocean is a major sink for anthropogenic carbon dioxide (CO2), with the CO2 uptake causing changes to ocean chemistry. To monitor these changes and provide a chemical background for biological and biogeochemical studies, high quality partial pressure of CO2 (pCO2) sensors are required, with suitable accuracy and precision for ocean measurements. Optodes have the potential to measure in situ pCO2 without the need for wet chemicals or bulky gas equilibration chambers that are typically used in pCO2 systems. However, optodes are still in an early developmental stage compared to more established equilibrator-based pCO2 systems. In this study, we performed a laboratory-based characterization of a time-domain dual lifetime referencing pCO2 optode system. The pCO2 optode spot was illuminated with low intensity light (0.2 mA, 0.72 mW) to minimize spot photobleaching. The spot was calibrated using an experimental gas calibration rig prior to deployment, with a determined response time (τ63) of 50 s at 25°C.
Membranes with hierarchical structure exist in biological systems, and bio-inspired building blocks have been used to grow synthetic analogues in the laboratory through self-assembly. The formation of these synthetic membranes is initiated at the interface of two aqueous solutions, one containing cationic pe Celebrating the 2016 RSC Prize and Award Winners
The aim of the present study was to clinically and histologically evaluate outcomes of alveolar ridge preservation technique using a collagen membrane associated to bovine-derived bone (MB), and a collagen membrane associated to porcine-derived bone (MP).
Uridine triacetate - Get up-to-date information on Uridine triacetate side effects, uses, dosage, overdose, pregnancy, alcohol and more. Learn more about Uridine triacetate
Three capillary dialyzers, with highly permeable membranes, have been compared for their capacity of epuration of blood urea nitrogen, creatinine, phosphorus, uric acid and beta 2 microglobulin, and for their respective protein losses. There were very little differences between the dialyzers for epuration of small uremic molecules, with no benefit due to high permeability membranes in comparison with conventional dialyzers. Protein losses may be important and have to be known. About beta 2 microglobulin, filtered quantities are not correlated to changes in serum levels, suggesting the presence of other mechanisms (adsorption on the membrane and generation during hemodialysis) which influence, together with epuration, perdialytic changes of serum beta 2 microglobulin concentrations.
The development of high-energy-density and low-cost battery systems appears to be a major limiting factor toward the real-world commercialization of electric cars (1). Traditional lithium-ion technology that relies on intercalation-type graphite anodes and metal oxide cathodes is approaching its theoretical limit in energy density and cost (2, 3). New chemistry beyond intercalation is desirable. Lithium metal batteries, such as Li-O2 and Li-S systems, promise lower-cost and higher-energy density (4, 5). This benefits from the coupling of high-capacity cathodes (O2/S) with a lithium metal anode, which exhibits an order of magnitude higher capacity than graphite (3,860 mAh g−1 vs. 370 mAh g−1) (6, 7). In the past decade, much effort has been devoted to extending the lifetime of cathodes; however, intrinsic challenges with Li metal are often not apparent, owing to the relative low areal current density and excess electrolyte generally used in such systems (8, 9).. It is vital to stabilize the ...