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Surface Coating (surface + coating)
Selected AbstractsResearch on Advanced Materials for Li-ion BatteriesADVANCED MATERIALS, Issue 45 2009Hong Li Abstract In order to address power and energy demands of mobile electronics and electric cars, Li-ion technology is urgently being optimized by using alternative materials. This article presents a review of our recent progress dedicated to the anode and cathode materials that have the potential to fulfil the crucial factors of cost, safety, lifetime, durability, power density, and energy density. Nanostructured inorganic compounds have been extensively investigated. Size effects revealed in the storage of lithium through micropores (hard carbon spheres), alloys (Si, SnSb), and conversion reactions (Cr2O3, MnO) are studied. The formation of nano/micro core,shell, dispersed composite, and surface pinning structures can improve their cycling performance. Surface coating on LiCoO2 and LiMn2O4 was found to be an effective way to enhance their thermal and chemical stability and the mechanisms are discussed. Theoretical simulations and experiments on LiFePO4 reveal that alkali metal ions and nitrogen doping into the LiFePO4 lattice are possible approaches to increase its electronic conductivity and does not block transport of lithium ion along the 1D channel. [source] Water-Based Gelcasting of Surface-Coated Silicon Nitride PowderJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 4 2001Yong Huang A layer of Y2O3,Al2O3, used as a sintering aid, was coated onto the surface of Si3N4 particles by the precipitation of inorganic salts from a water-based solution containing Al(NO3)3, Y(NO3)3, and urea. The electrokinetic and colloidal characteristics of the Si3N4 powder were changed significantly by the coating layer. As a result, dispersion of the Y2O3,Al2O3 -coated Si3N4 powder was significantly greater than that of the original powder. Furthermore, the Y2O3,Al2O3 coating layer prevented the hydrogen-gas-discharging problem that occurred during gelcasting of the original Si3N4 powder because of reaction between the uncoated powder and the basic aqueous solution in suspension. Surface coating, as well as the gelcasting process, significantly improved the microstructure, room-temperature bending strength, and Weibull modulus of the resulting ceramic bodies. [source] CE coupled to MALDI with novel covalently coated capillariesELECTROPHORESIS, Issue 4 2010Stefan Bachmann Abstract CE offers the advantage of flexibility and method development options. It excels in the area of separation of ions, chiral, polar and biological compounds (especially proteins and peptides). Masking the active sites on the inner surface of a bare fused silica capillary wall is often necessary for CE separations of basic compounds, proteins and peptides. The use of capillary surface coating is one of the approaches to prevent the adsorption phenomena and improve the repeatability of migration times and peak areas of these analytes. In this study, new capillary coatings consisting of (i) derivatized polystyrene nanoparticles and (ii) derivatized fullerenes were investigated for the analysis of peptides and protein digest by CE. The coated capillaries showed excellent run-to-run and batch-to-batch reproducibility (RSD of migration time ,0.5% for run-to-run and ,9.5% for batch-to-batch experiments). Furthermore, the capillaries offer high stability from pH 2.0 to 10.0. The actual potential of the coated capillaries was tested by combining CE with MALDI-MS for analysing complex samples, such as peptides, whereas the overall performance of the CE-MALDI-MS system was investigated by analysing a five-protein digest mixture. Subsequently, the peak list (peptide mass fingerprint) generated from the mass spectra of each fraction was entered into the Swiss-Prot database in order to search for matching tryptic fragments using the MASCOT software. The sequence coverage of analysed proteins was between 36 and 68%. The established technology benefits from the synergism of high separation efficiency and the structure selective identification via MS. [source] Atmospheric molding of ionic copolymer MALDI-TOF/MS arrays: A new tool for protein identification/profilingELECTROPHORESIS, Issue 24 2006Alexander Muck Abstract An atmospheric molding protocol has been used to prepare an ionic methacrylate-based copolymer sample support chips for MALDI (pMALDI)-MS by targeting selected groups of various monomers copolymerized during molding, namely, carboxy, sulfo, dimethylalkyamino, and trimethylalkylammonium groups. The new disposable array chips provide analyte-oriented enhancement of protein adsorption to the modified substrates without requiring complicated surface coating or derivatization. The MALDI-MS performance of the new ionic copolymer chips was evaluated for lysozyme, ,-lactoglobulin,A, trypsinogen and carbonic anhydrase,I using washing with solutions prepared in pH or ionic strength steps. On cationic chips, the proteins are washed out at pH lower than their pI values, and on anionic chips at pH higher than their pI values. The ability of the microfabricated pMALDI chip set to selectively adsorb different proteins from real samples and to significantly increase their MS-signal was documented for the transmembrane photosystem,I protein complex from the green alga Chlamydomonas reinhardtii. The proteins were almost exclusively adsorbed according to calculated pI values and grand average of hydropathy (GRAVY) indexes. The new disposable chips reduce manipulation times and increase measurement sensitivity for real-world proteomic samples. The simple atmospheric molding procedure enables additional proteomic operations to be incorporated on disposable MALDI-MS integrated platforms. [source] Research on corrugated multi-louvered fins under dehumidificationHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 5 2001Hiroshi Osada Abstract To enhance automotive evaporator wet-fin performances, the main task is to promote the draining of condensed water. An accurate and convenient apparatus estimating the fin performances has been developed. Through the measurement of corrugated multi-louvered fin performances and the visualization of condensed water draining by this apparatus, it was clarified that fin geometries, surface coating, and evaporator installation strongly contributed to the efficiency of draining and fin performances. © 2001 Scripta Technica, Heat Trans Asian Res, 30(5): 383,393, 2001 [source] Low Adhesive Surfaces that Adapt to Changing EnvironmentsADVANCED MATERIALS, Issue 18 2009Roman Sheparovych A responsive/adaptive nonadhesive surface coating that combines hydrophobic particles and hydrophilic polymer chains in a tethered composite coating is demonstrated. Rigid particles provide low contact area, while a selective segregation of polymer chains upon changing the surrounding environment from vapors to liquids and vice versa adapts the low-adhesive property of the composite surface. [source] Facile Conjugation of Biomolecules onto Surfaces via Mussel Adhesive Protein Inspired CoatingsADVANCED MATERIALS, Issue 4 2009Haeshin Lee A new surface bioconjugation strategy is presented. A polydopamine surface coating provides chemical activation on material surfaces, is resistant to hydrolysis, and offers selectivity in coupling of biomolecules via nucleophilic groups through simple pH control. Control of orientation of immobilized biomolecules may be possible using terminally modified DNA or His-containing proteins. [source] Tracking bio-molecules in live cells using quantum dotsJOURNAL OF BIOPHOTONICS, Issue 4 2008Yun-Pei Chang Abstract Single particle tracking (SPT) techniques were developed to explore bio-molecules dynamics in live cells at single molecule sensitivity and nanometer spatial resolution. Recent developments in quantum dots (Qdots) surface coating and bio-conjugation schemes have made them most suitable probes for live cell applications. Here we review recent advancements in using quantum dots as SPT probes for live cell experiments. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Avecor Trillium Oxygenator Versus Noncoated Monolyth Oxygenator: A Prospective Randomized Controlled StudyJOURNAL OF CARDIAC SURGERY, Issue 4 2008Frédéric Vanden Eynden M.D. This study was designed to study the effects of the surface coating of a hollow fiber membrane oxygenator on coagulation, inflammation markers, and clinical outcomes. The biomaterials used to coat the membrane include heparin, polyethylene oxide chains (PEO), and sulfate/sulfonate groups. The coated membrane was compared to an uncoated oxygenator made of polypropylene. Methods: Two hundred patients who were scheduled to undergo valve repair and/or replacement surgery with or without coronary surgery were enrolled in the study. The patients were randomized to undergo CPB with either the Avecor oxygenator with TrilliumÔ (Medtronic, Minneapolis, MN, USA), a biopassive surface, or the Monolyth (Sorin, Irvine, CA, USA) oxygenator without coating. The primary and secondary endpoints were the differences between these oxygenators in regard to patients' biochemistry, coagulation profiles, inflammatory mediators, and clinical outcomes, including blood loss and neurological events. Results: There were no differences between the two groups in terms of biochemistry, coagulation profile, inflammatory mediator release, and blood loss. Five patients in the Avecor group showed clinical evidence of a stroke confirmed with computerized tomography (CT) scan imaging, and none in the noncoated oxygenator group. Conclusion: The oxygenator Avecor offers similar results in terms of inflammation and coagulation profiles and blood loss during valvular surgery compared to a standard uncoated control oxygenator. The rate of neurological events was unusually elevated in the former group of patients, with only speculative explanation at this point. Further studies are warranted to clarify this aspect. [source] Microstructure,property,quality-correlated paint design: An LMC-based approachAICHE JOURNAL, Issue 1 2009Jie Xiao Abstract Paint is designed to offer various chemical and physical properties for surface protection, styling, and appearance. Nevertheless, the anticipated quality of the surface coating is frequently unsatisfactory, which is often attributed to paint formulation. As new demands on coating performance continuously emerge, paint formulation design becomes much more challenging than ever. It is recognized that paint design can be significantly improved with the help of advanced computational methods, as they can provide great freedom and control over the investigation of paint formulation through any number of in silico experiments virtually under any application conditions. This article introduces a lattice Monte Carlo based computational methodology for paint formulation design. By this methodology and structural analysis techniques, a variety of correlations among paint material, curing condition, coating microstructure, and coating qualities can be generated, which are critical for the development of superior paint formulations. A comprehensive study on acrylic-melamine-based paint design and analysis demonstrates the methodological efficacy. © 2008 American Institute of Chemical Engineers AIChE J, 2009 [source] Hydroxyapatite Coating on Thermally Oxidized Titanium SubstratesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2001Minkmas Vatanatham Titanium substrates were oxidized in oxygen or air at temperatures of 600°,800°C, then immersed in solutions of 2.0mM, 20.7mM CaCl2 and 1.2mM,12.4mM KH2PO4 for aging periods of 0.5,10 d. The titanium surface was successfully coated with hydroxyapatite (HAP) when the substrates were oxidized in oxygen gas at 610°C for 1 h and then aged in a solution of 2.00mM Ca2+ and 1.20mM PO43,. The Ca/P ratio of the surface coating increased toward its stoichiometric HAP value (return 10/6) as the aging time increased; the Ca/P ratio attained a value of 1.66 after 10 d. [source] Synthesis of Fluorinated Hyperbranched Polymers and Their Use as Additives in Cationic PhotopolymerizationMACROMOLECULAR MATERIALS & ENGINEERING, Issue 7 2005Marco Sangermano Abstract Summary: A fluorine containing hyperbranched polymer was synthesized by modifying an aromatic-aliphatic hyperbranched polyester with a semifluorinated alcohol via a Mitsunobu reaction and was subsequently used as an additive in cationic photopolymerization of an epoxy resin. The remaining OH groups of the fluorinated hyperbranched polymer interact with the polymeric carbocation through a chain-transfer mechanism inducing an increase in the final epoxy conversion. The fluorinated HBP induces modification of bulk and surface properties, with an increase in Tg and surface hydrophobicity already reached at very low concentration. The HBFP additive can, therefore, protect the coatings from aggressive solvents, increases hardness, and allows the preparation of a low energy surface coating. Synthesis of fluorinated hyperbranched polyester. [source] Damage control , a possible non-proteolytic role for ubiquitin in limiting neurodegenerationNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 2 2001D. A. Gray Ubiquitin can be detected in the neuronal and glial inclusions that are the diagnostic hallmarks of a number of human neurodegenerative diseases. It has been assumed that the presence of ubiquitin signifies the failed attempt of the cell to remove abnormal protein structures, which have been allowed to aggregate. The burden of abnormal protein arising from genetic mutations or cumulative oxidative damage might in the course of time overwhelm the ubiquitin-proteasome pathway (whose responsibility it is to eliminate misfolded or damaged proteins). However, ubiquitin may still serve a protective purpose distinct from its role in proteolysis. The physical properties of ubiquitin are such that a surface coating of ubiquitin should preclude further growth of the aggregate, prevent non-productive interactions, and conceal the contents from detection mechanisms that might ultimately kill the cell. This ,nonstick coating' hypothesis makes predictions about the nature of the conjugated ubiquitin and the consequences of removing it. [source] Characterization of Vernix Caseosa as a Natural Biofilm: Comparison to Standard Oil-Based OintmentsPEDIATRIC DERMATOLOGY, Issue 4 2000Maria Imelda B. Bautista M.D. Such infants have a structurally immature stratum corneum and lack a surface coating of vernix caseosa. In this study we examined the short-term effects of topical application of vernix caseosa to human skin and contrasted these effects with commonly used ointments and water-in-oil emulsions. Specifically, vernix, Eucerin®, Aquaphor®, and petrolatum were applied to the volar skin surface of adult volunteers. Surface electrical capacitance (SEC) and transepidermal water loss (TEWL) were measured as indices of surface hydration. Sorption-desorption profiles were performed to determine skin surface hydrophobicity. Particular attention was given to monitoring the acute (0,120 minutes) changes following vernix treatment in order to compare these effects with earlier reports on the rate of skin surface drying in newborn infants following birth. Immediately after vernix application there was an increase in the rate of water loss from the skin surface. Relative to control skin and skin treated with the ointments and water-in-oil emulsions, the application of vernix to freshly bathed human skin resulted in a unique profile of temporal change in baseline surface hydration, moisture accumulation, and water-holding capacity. These results demonstrate major differences between human vernix and standard oil-based topical ointments. The results provide a framework for discussing the various properties of topical barriers applied to the very low birthweight infant. [source] Starch-filled ternary polymer composites.POLYMER ENGINEERING & SCIENCE, Issue 10 2004II: Room temperature tensile properties The room temperature tensile properties of granular starch-filled low-density polyethylene (PE) and starch-filled blends of PE and poly(hydroxy ester ether) (PHEE) are presented. At low filler contents (,f), the filled PE:PHEE blend has a higher yield stress and tensile strength than either the starch/PE composites or the unfilled matrix. The increase in the yield stress indicates that matrix yielding occurs before debonding. At high filler contents, the tensile strength of the filled blend is again greater than the strength of the starch/PE composites. This increase in strength is the result of higher debonding stresses in the ternary composite. In both materials there is a change in the deformation process at a critical filler content, ,cr. Below ,cr, deformation involves the growth of debonded regions; above ,cr, deformation is confined to narrow damaged zones. There is a reduction in the strain at failure when this change in the deformation process occurs. Although the PHEE surface coating affects the debonding stress and the tensile strength, it does not affect the strain at failure or the tensile modulus. For both composite materials, the increase in modulus with ,f can be adequately described using a simplified form of the Kerner equation. Polym. Eng. Sci. 44:1839,1847, 2004. © 2004 Society of Plastics Engineers. [source] Preparation of carbon nanofibres through electrospinning and thermal treatment,POLYMER INTERNATIONAL, Issue 12 2009Cheng-Kun Liu Abstract Electrospinning is a versatile process to obtain continuous carbon nanofibres at low cost. Thermoplastic and thermosetting polymer precursors are utilized to prepare electrospun carbon nanofibres, activated carbon nanofibres through chemical and/or physical activation and functionalized composite carbon nanofibres by surface coating or electrospinning a precursor solution tailored with nanomaterials. Many promising applications of electrospun carbon nanofibres can be expected if appropriate microstructural, mechanical and electrical properties become available. This article provides an in-depth review of the research activities regarding several varieties and performance requirements of precursor nanofibres, polyacrylonitrile-based carbon nanofibres and their functionalized products, and carbon nanofibres from other precursors. Copyright © 2009 Society of Chemical Industry [source] Gas-phase hydrodechlorination of chlorobenzenes over silica-supported palladium and palladium,ytterbium,APPLIED ORGANOMETALLIC CHEMISTRY, Issue 6-7 2003Satyakrishna Jujjuri Abstract A 5% w/w palladium loading on silica has been achieved via impregnation of the support with Pd(C2H3O2)2 and { (DMF)10Yb2[Pd(CN)4]3} , precursors to deliver monometallic (Pd/SiO2) and bimetallic (Yb,Pd/SiO2) catalyst systems respectively. The catalytic action of each has been assessed in the continuous gas-phase hydrodechlorination (HDC) of chlorobenzene (CB) and 1,2-dichlorobenzene (1,2-DCB) (T = 423 K, inlet chlorine/palladium mol ratio of 5 × 103 h,1) and the hydrogenation of benzene (T = 423 K, inlet C6H6/palladium mol ratio of 35 h,1). Activation of both catalysts delivered similar palladium crystallite size distributions with an average palladium diameter of 5,6 nm where the ytterbium component (in Yb,Pd/SiO2) was present as a thin surface coating. The Pd,Yb bimetallic exhibited significantly higher HDC and hydrogenation activities, the former manifested by significantly greater fractional dechlorinations and benzene selectivities/yields. Yb/SiO2 proved inactive in terms of promoting hydrogen scission or addition and the promotional effect of ytterbium in Yb,Pd/SiO2 is discussed in terms of electron donation and hydrogen transfer via surface YbH2. Under identical reaction conditions, a lower HDC activity was recorded for 1,2-DCB compared with CB, a response that is attributed to steric constraints allied to the deactivating effect of the second chlorine substituent. Both Pd/SiO2 and Yb,Pd/SiO2 exhibited a decline in HDC activity with time-on-stream, but the bimetallic was significantly more resistant to deactivation. Copyright © 2003 John Wiley & Sons, Ltd. [source] Effects of defrosting period on mold adhesion force of epoxy molding compoundASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 2 2009Hwe-Zhong Chen Abstract In integrated circuit (IC) packaging, when epoxy-molding compound (EMC) is filled in the mold cavity and cured in the mold, adhesion occurs in the interface between EMC and the mold surface. Too large an adhesion force can cause many problems. For example, too large an adhesion force may damage an IC during ejection and cause the package to fail and thus lower the yield rate. To resolve mold adhesion problems, improving the mold design and applying suitable surface treatments, such as mold surface coating, are the common approaches. Applying suitable surface coating is a more popular and practical approach. Defrosting is a process to increase the frozen EMC temperature to room temperature, and to retain it at room temperature for some period before molding. It is a common practice to put EMC under required atmospheric environment during defrosting. It has been found by molding engineers that increased defrosting period will increase the frequency of mold cleaning. But there is no quantitative description on how much the adhesion force increases during the defrosting process. This paper describes the use of a semiautomatic EMC adhesion force test instrument to measure the normal adhesion force between the mold surface and EMC. By measuring the adhesion force, one can quantify how much adhesion force exists between EMC and the mold surface under different defrosting periods. The results show that it is best to use the EMC with 24,32 h of defrosting, to prevent excessive amount of mold adhesion force and it has been found that the adhesion force of the 24 h defrosting period will be 24% less than that of the 48 h defrosting period. Decreasing moisture absorption will decrease the increase in adhesion force for prolonged defrosting period cases. Copyright © 2008 Curtin University of Technology and John Wiley & Sons, Ltd. [source] The zeta potential of surface-functionalized metallic nanorod particles in aqueous solutionELECTROPHORESIS, Issue 5 2008George M. Dougherty Abstract Metallic nanoparticles suspended in aqueous solutions and functionalized with chemical and biological surface coatings are important elements in basic and applied nanoscience research. Many applications require an understanding of the electrokinetic or colloidal properties of such particles. We describe the results of experiments to measure the zeta potential of metallic nanorod particles in aqueous saline solutions, including the effects of pH, ionic strength, metallic composition, and surface functionalization state. Particle substrates tested include gold, silver, and palladium monometallic particles as well as gold/silver bimetallic particles. Surface functionalization conditions included 11-mercaptoundecanoic acid (MUA), mercaptoethanol (ME), and mercaptoethanesulfonic acid (MESA) self-assembled monolayers (SAMs), as well as MUA layers subsequently derivatized with proteins. For comparison, we present zeta potential data for typical charge-stabilized polystyrene particles. We compare experimental zeta potential data with theoretically predicted values for SAM-coated and bimetallic particles. The results of these studies are useful in predicting and controlling the aggregation, adhesion, and transport of functionalized metallic nanoparticles within microfluidic devices and other systems. [source] Influence of stability on the acute toxicity of CdSe/ZnS nanocrystals to Daphnia magnaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2010Heather E. Pace Abstract The acute toxicity of polymer-coated CdSe/ZnS quantum dots (QDs) to Daphnia magna was investigated using 48-h exposure studies. The principal objective was to relate the toxicity of QDs to specific physical and chemical aspects of the QD. As such, two different CdSe core diameters, 2,nm QDs (green-emitting) and 5,nm QDs (red-emitting), and two different surface coatings, polyethylene oxide (PEO) and 11-mercaptoundecanoic acid (MUA) were studied. The QDs were characterized before and after the 48-h exposure using fluorescence, ultrafiltrations (3 kDa), and inductively coupled plasma-atomic emission spectrometry (ICP-AES) metal analysis. In addition, flow field flow fractionation-inductively coupled plasma-mass spectrometry (Fl FFF-ICP-MS) was used as a more extensive characterization technique to determine particle size and composition as well as identify other potential constituents in the QD solutions. The more stable QDs (PEO) were found to be less acutely toxic than the QDs with accelerated dissolution (MUA), suggesting QD stability has significant impact on the nanoparticles' short-term toxicity. The emergence of dissolved Cd2+ in solution indicates that the toxicity of the MUA QDs is likely due to Cd poisoning, and a mass-based dose response occurred as a consequence of this mode of action. Alternatively, the PEO QDs caused acute toxicity without observed particle dissolution (i.e., no detectable metals were solubilized), suggesting an alternative mode of toxic action for these nanoparticles. Results of the present study suggest that using particle number, instead of mass, as a dose metric for the PEO QDs, produces markedly different conclusions, in that smaller core size does not equate to greater toxicity. Environ. Toxicol. Chem. 2010;29:1338,1344. © 2010 SETAC [source] Colours and Metallic Sheen in Beetle Shells , A Biomimetic Search for Material Structuring Principles Causing Light Interference,ADVANCED ENGINEERING MATERIALS, Issue 4 2008T. Lenau Abstract Visual aesthetic has always played a vital role for the success of many products. This includes colours and glossiness and metal appearance which is often achieved using surface coatings. Present coating techniques do, however, have limitations. It is difficult to reach very bright and brilliant colours, colours tend to fade over time and many of the materials and coating technologies pollute and have other environmental problems. Beetles in nature have many of the desired properties: They have appealing brilliant colours and some even with metallic appearance. It is noticeable that the colours are long lasting as some of the beetles we have studied at the zoological museum are more than 200 years old and have colours and brightness as if they were still alive. Furthermore, the beetles in nature are part of sustainable ecosystems, which means that they are made from renewable materials that are broken down and recycled when the beetle dies. Beetles also possess another and very attractive property: Their metallic look originates from structures in organic materials which is both electrically and thermal insulating. The industrial perspective is to be able to manufacture products with attractive metallic surfaces that do not feel so cold to touch as their metallic counterparts and that do not represent an electrical shock hazard. [source] Fabrication of Continuous and Segmented Polymer/Metal Oxide Nanowires Using Cylindrical Micelles and Block Comicelles as TemplatesADVANCED MATERIALS, Issue 18 2009Hai Wang Cylindrical micelles were added as templates to sol,gel reaction mixtures to yield highly elongated polymer/inorganic nanostructures with smooth nanothin surface coatings of silica, zirconia, or alumina. Differences in the templating activity of neutral or cationic coronas can be exploited by using triblock comicelles to produce discrete nanocylinders with spatially isolated domains of titania surface deposition. [source] Antiadhesion Surface Treatments of Molds for High-Resolution Unconventional Lithography,ADVANCED MATERIALS, Issue 23 2006J. Lee A new strategy to achieve antiadhesion surface coatings is introduced. The approach, which uses molds coated in a thin film of poly(dimethylsiloxane) (PDMS, see figure) to achieve the antiadhesive surfaces, is applicable to virtually any type of mold material due to the use of silane chemistry and the low surface energy of PDMS. This allows simple and rapid replication of high complexity, high-aspect-ratio nanostructures with excellent replication fidelity. [source] Highly Functional Poly(meth)acrylates via Cascade ReactionMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 2 2009Dragos Popescu Abstract A new route to the synthesis of highly functional and reactive polymethacrylates via cascade reactions comprising enzymatically and chemically catalyzed steps is presented. Transacylation of methyl acrylate and methyl methacrylate as substrates with different functional alcohols in the presence of Novozyme 435 leads to a mixture of functional monomers, which in a subsequent step was copolymerized via free radical polymerization, resulting in polymethacrylates with predefined functionalities. Hydrophilic, hydrophobic, as well as ionic methacrylate repeating units were assembled in a copolymer and adjusted for surface coatings. [source] Water-Based Coatings Based on Mixtures of Acrylic Dispersions and Alkyd EmulsionsMACROMOLECULAR SYMPOSIA, Issue 1 2009Patrick J. J. Kivit Abstract In this work acrylic dispersions were mixed with alkyd emulsions to obtain coatings that lower the amount of volatile organic compounds (VOC) in surface coatings. The advantage of this approach is that the fast drying of the acrylic is combined with the good film properties of the alkyd. Films produced with an alkyd and a soft acrylic (AA1) did not exhibit good film properties. Whereas, films produced with a hard acrylic (SA1 and AA2) and a soft alkyd gave films with good appearance, appropriate drying times, superior pendulum hardness and promising values of gloss. VOC was calculated below 25,g/L. The novel mixtures may be applied as high gloss enamels for architectural coatings. [source] Systematic comparison of surface coatings for protein microarraysPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 18 2005Birgit Guilleaume Dr. Abstract To process large numbers of samples in parallel is one potential of protein microarrays for research and diagnostics. However, the application of protein arrays is currently hampered by the lack of comprehensive technological knowledge about the suitability of 2-D and 3-D slide surface coatings. We have performed a systematic study to analyze how both surface types perform in combination with different fluorescent dyes to generate significant and reproducible data. In total, we analyzed more than 100 slides containing 1152 spots each. Slides were probed against different monoclonal antibodies (mAbs) and recombinant fusion proteins. We found two surface coatings to be most suitable for protein and antibody (Ab) immobilization. These were further subjected to quantitative analyses by evaluating intraslide and slide-to-slide reproducibilities, and the linear range of target detection. In summary, we demonstrate that only suitable combinations of surface and fluorescent dyes allow the generation of highly reproducible data. [source] Blood Biocompatibility Assessment of an Intravenous Gas Exchange DeviceARTIFICIAL ORGANS, Issue 9 2006Trevor A. Snyder Abstract:, To treat acute lung failure, an intravenous membrane gas exchange device, the Hattler Catheter, is currently under development. Several methods were employed to evaluate the biocompatibility of the device during preclinical testing in bovines, and potential coatings for the fibers comprising the device were screened for their effectiveness in reducing thrombus deposition in vitro. Flow cytometric analysis demonstrated that the device had the capacity to activate platelets as evidenced by significant increases in circulating platelet microaggregates and activated platelets. Thrombus was observed on 20 ± 6% of the surface area of devices implanted for up to 53 h. Adding aspirin to the antithrombotic therapy permitted two devices to remain implanted up to 96 h with reduced platelet activation and only 3% of the surface covered with thrombus. The application of heparin-based coatings significantly reduced thrombus deposition in vitro. The results suggest that with the use of appropriate antithrombotic therapies and surface coatings the Hattler Catheter might successfully provide support for acute lung failure without thrombotic complications. [source] Implant surfaces and design (Working Group 4)CLINICAL ORAL IMPLANTS RESEARCH, Issue 2009Niklaus P. Lang Abstract Introduction: The remit of this working group (4) was to update existing knowledge on the effects of implant surface topography, composition and design on bone integration and re-osseointegration. Material and methods: Based on five narrative reviews that were performed following a defined search strategy, clinical implications as well as suggestions for further research have been formulated. Results: The results and conclusions of the review processes in the following papers together with the group consensus, clinical implications and directions for future research are presented: 1. Effects of titanium surface topography on bone integration. 2. Effects of implant surface coatings and composition on bone integration (two reviews). 3. Effects of different implant surfaces and designs on marginal bone level alterations. 4. Re-osseointegration onto previously contaminated implant surfaces. [source] | |||||||||||||||||||||||||||||||