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Solid Surface (solid + surface)
Selected AbstractsThickening Processes of Lamellar Crystal Monolayers of a Low-Molecular-Weight PEO Fraction on a Solid SurfaceMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 6 2007Xuemei Zhai Abstract Using hot-stage atomic force microscopy, the thickening processes of monolayer crystals of PEO (,=,5,000 g,·,mol,1 and ,=,1.008) from one-folded (FC1) to extended-chain (EC) lamellae are experimentally monitored at three temperatures: 50, 52, and 58,°C. At 50,°C some small areas in large FC1 crystals spontaneously thicken into EC crystals. At 52,°C the spontaneously thickened area further expands so as to inductively thicken the entire FC1 lamella into EC lamella. At 58,°C EC crystals first force the adjacent FC1 crystals to melt and then absorb the melted molecules to grow laterally into large EC lamellae till all FC1 lamellae vanish. The three thickening steps express the main thickening process of lamellar crystals from a metastable state to another metastable (or equilibrium) state. The possible mechanisms are discussed in the text. [source] Reactions on a Solid Surface.CHEMINFORM, Issue 5 2005A Simple, Crafts Acylation Reaction over Zinc Oxide (ZnO) as a New Catalyst., Economical, Efficient Friedel Abstract For Abstract see ChemInform Abstract in Full Text. [source] Reactions on a Solid Surface.CHEMINFORM, Issue 23 2004A Simple, Amines over Al2O3., Economical, Efficient Acylation of Alcohols No abstract is available for this article. [source] Nitrogen Trifluoride as a Bifunctional Lewis Base: Implications for the Adsorption of NF3 on Solid SurfacesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 5 2004Paola Antoniotti Abstract The structure, stability, and thermochemistry of isomeric adducts between NF3 and the Lewis acids BH3,nFn (n = 0,3) have been investigated at the coupled-cluster and at the Gaussian-3 (G3) level of theory. At the CCD/cc-pVDZ level both the nitrogen- and the fluorine-coordinated structures of all BH3,nFn,(NF3) (n = 0,3) adducts were characterized as true minima on the potential energy surface, thus providing the first theoretical evidence for the behavior of NF3 as a bifunctional Lewis base when interacting with neutral Lewis acids. At the G3 level, and 298.15 K, including the contribution of the entropy term, the H3B,NF3 adduct is predicted to be more stable than H3B,F,NF2 by 4.3 kcal mol,1; this free energy difference is 3.7 kcal mol,1 at the CCSD(T)/cc-pVTZ//CCD/cc-pVDZ level of theory. Conversely, at the latter computational level, the fluorine-coordinated isomers of the BH2F,(NF3), BHF2,(NF3), and BF3,(NF3) adducts are practically degenerate with the nitrogen-coordinated ones. BH3,nFn,(NF3) (n = 0,3) complexes feature typical bond dissociation energies of ca. 1,2 kcal mol,1, and are predicted to be thermodynamically stable only at low temperatures. However, the appreciable influence of the basis set superposition error (BSSE) prevents a quantitative assessment of these small computed dissociation energies. Finally, we briefly discuss the implications of our calculations for the adsorption of NF3 on solid surfaces. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Engineering LacI for Self-Assembly of Inorganic Nanoparticles on DNA Scaffold through the Understanding of LacI Binding to Solid SurfacesADVANCED FUNCTIONAL MATERIALS, Issue 8 2009Haibin Chen Abstract The potential of utilizing the DNA binding protein lac repressor (LacI) to organize inorganic nanoparticles (NPs) is explored in this study. A peptide cognitive of both SiO2 and TiO2 simultaneously (STB1, -CHKKPSKSC-) is genetically engineered into the C-terminus of LacI to give LacI-STB1, and the inserted STB1 peptides in the context of LacI-STB1 molecules are shown to actively interact with both SiO2 and TiO2. Wild-type LacI is found to interact with the two surfaces at its flexible N-terminal DNA binding domain, and LacI-STB1 exhibits much stronger binding affinity to both surfaces by harnessing a second binding region (STB1 peptide) fused at its C-terminus. The quantitative analysis of binding kinetics reveals that, compared to wild-type LacI with one binding region (N-terminus), two remote binding regions (N-terminus and C-terminus) in LacI-STB1 do not lead to faster adsorption rates to the two surfaces, but remarkably slow down the desorption rates. Finally, using LacI-STB1 as a linker, the successful assembly of a sandwich nanostructure of DNA/LacI-STB1/TiO2 NPs is demonstrated using surface plasmon resonance (SPR) measurements and TEM. The demonstrated LacI-STB1-mediated assembly of TiO2 NPs on DNA scaffold may provide a generic platform for controlled spatial arrangement of various nanoparticles of engineering interest. [source] Fabrication of Oriented Multilayers of Photosystem I Proteins on Solid Surfaces by Auto-Metallization,ADVANCED MATERIALS, Issue 2 2008L. Frolov AFM phase image of PS I (Top) and platinized PS I (bottom) monolayers. The Pt patches serve as junctions for fabrication of oriented multilayer by covalent binding of cysteine mutants through the formation of sulfide bonds with the Pt. A larger absorption cross section and the serial arrangement resulted in an increase in the photopotential generated by the dry multilayers. [source] Controlled Radical Polymerization of Vaporized Vinyl Monomers on Solid Surfaces under UV IrradiationMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 4 2004Mikio Yasutake Abstract Summary: In order to prepare well-defined polymers on solid surfaces in the gas phase, a gas phase-assisted surface polymerization (GASP) of vinyl monomers was carried out on solid surfaces pre-coated with a photoiniferter, 2-cyanoprop-2-yl N,N,-dimethyldithiocarbamate, under UV irradiation. The GASP of methyl methacrylate (MMA) resulted in the formation of polymer on the surfaces and showed a proportional relationship between and polymer yield. Consecutive copolymerization of MMA and styrene led to the formation of a block copolymer, which was confirmed by a selective solvent fractionation method. These results demonstrate that controlled radical polymerization of vaporized monomer occurred on the solid surfaces. Expected mechanism of GASP under UV irradiation. [source] Reactions at Solid Surfaces.ANGEWANDTE CHEMIE, Issue 31 2010Von Gerhard Ertl. John Wiley & Sons, Hoboken 2009. 208,S., geb. 57.90,,.,ISBN 978-0470261019 [source] Nanometer-Sized Fluorous Fullerene Vesicles in Water and on Solid Surfaces,ANGEWANDTE CHEMIE, Issue 9 2010Tatsuya Homma Ein neuer Dreh für Buckyballs: Ein fluoriertes Fullerenamphiphil ohne das übliche Motiv ,polarer Kopf/nichtpolarer Schwanz" bildet über die Kohäsionskraft des Fullerens in Wasser Vesikeln (F grün, C grau). Die fluorierten Ketten nehmen die Vesikeloberfläche ein, und Vesikellösungen können Perfluoroctan lösen. Anders als Lipidvesikeln ist die fluorierte Vesikel sehr robust und behält ihre Kugelform sogar auf einem festen Substrat im Hochvakuum bei. [source] Self-Assembly of an Alkylated Guanosine Derivative into Ordered Supramolecular Nanoribbons in Solution and on Solid SurfacesCHEMISTRY - A EUROPEAN JOURNAL, Issue 13 2007Stefano Lena Dr. Abstract We report on the synthesis and self-assembly of a guanosine derivative bearing an alkyloxy side group under different environmental conditions. This derivative was found to spontaneously form ordered supramolecular nanoribbons in which the individual nucleobases are interacting through H-bonds. In toluene and chloroform solutions the formation of gel-like liquid-crystalline phases was observed. Sub-molecularly resolved scanning tunneling microscopic imaging of monolayers physisorbed at the graphite,solution interface revealed highly ordered two-dimensional networks. The recorded intramolecular contrast can be ascribed to the electronic properties of the different moieties composing the molecule, as proven by quantum-chemical calculations. This self-assembly behavior is in excellent agreement with that of 5,- O -acylated guanosines, which are also characterized by a self-assembled motif of guanosines that resembles parallel ribbons. Therefore, for guanosine derivatives (without sterically demanding groups on the guanine base) the formation of supramolecular nanoribbons in solution, in the solid state, and on flat surfaces is universal. This result is truly important in view of the electronic properties of these supramolecular anisotropic architectures and thus for potential applications in the fields of nano- and opto-electronics. [source] Bioinspired Ribbed Nanoneedles with Robust SuperhydrophobicityADVANCED FUNCTIONAL MATERIALS, Issue 4 2010Xi Yao Abstract The robustness of superhydrophobicity is a fundamental issue for the applications of water-repellent materials. Inspired by the hierarchical structures of water-strider legs, this work describes a new water-repellent material decorated with ribbed, conical nanoneedles, successfully achieved on the surface of copper and consisting of copper hydroxide nanoneedle arrays sculptured with nanogrooves. The behavior of water drops on an as-prepared surface under various external disturbances is investigated. It is shown in particular that squeezing and relaxing drops between two such surfaces leads to a fully reversible exploration of the solid surface by the liquid, which is distinct from other superhydrophobic surfaces. This unique character is attributed to the penetrating Cassie state that occurs at the ribbed, conical nanoneedles. The proprietary lateral nanogrooves can, not only vigorously support the enwrapped liquid-air interface when a force is applied to the drop, but also provide reliable contact lines for the easy de-pinning of the deformed interface when the force is released from the drop. The results confirm the exceptional ability of strider legs to repel water, and should help to further the design of robust water-repellent materials and miniaturized aquatic devices. [source] Real-Time Liquid Crystal pH Sensor for Monitoring Enzymatic Activities of PenicillinaseADVANCED FUNCTIONAL MATERIALS, Issue 23 2009Xinyan Bi Abstract A liquid crystal (LC)-based pH sensor for real-time monitoring of changes in localized pH values near a solid surface is reported, along with its application for the detection of enzymatic activities. It is found that 4-cyano-4,-pentylbiphenyl (5CB), when doped with 4,-pentyl-biphenyl-4-carboxylic acid (PBA), shows a bright-to-dark optical response to a very small change in pH (from 6.9 to 7.0). The pH-driven optical response can be explained by using orientational transitions of 5CB induced by the protonation and deprotonation of PBA at the aqueous/LC interface. Because of its high pH sensitivity, the LC-based sensor is further exploited for monitoring local pH changes resulting from enzymatic reactions. As a proof of concept, the hydrolysis of penicillin G by surface-immobilized penicillinase is monitored using the system, even when the concentration of penicillin G is as low as 1,nM. This type of LC-based sensor may find potential utilities in high-throughput screening of enzyme substrates and enzyme inhibitors. [source] A study on thermal conductivity of a quasi-ordered liquid layer on a solid substrateHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 7 2007Xiao-Yan Shi Abstract In the present paper, a study on thermal conductivity of a quasi-ordered liquid layer on a solid surface was performed by molecular dynamic simulation. Results showed that the motion of the molecules and their radial distribution function in the quasi-ordered liquid layer were similar to those of solid molecules. By using the Green,Kubo formula, the thermal conductivity of the layer was calculated. It was found that it increased with the increase of the parameters of ordering. The size effect and the influence of the boundary condition were also discussed. © 2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(7): 429,434, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20171 [source] Drug Delivery: Drawing Lithography: Three-Dimensional Fabrication of an Ultrahigh-Aspect-Ratio Microneedle (Adv. Mater.ADVANCED MATERIALS, Issue 4 20104/2010) Ultrahigh-aspect-ratio microneedles can be fabricated via "drawing lithography", a novel technique in which a thermosetting polymer is directly drawn from a two-dimensional solid surface without the need for a mask and light irradiation. Kwang Lee and co-workers demonstrate this technique on p. 483. The inside cover shows a scanning electron microscopy (SEM) image of three-dimensional structures with ultrahigh aspect ratios, potentially suitable as drug-delivery devices that could replace hypodermic syringes. [source] Drawing Lithography: Three-Dimensional Fabrication of an Ultrahigh-Aspect-Ratio MicroneedleADVANCED MATERIALS, Issue 4 2010Kwang Lee Drawing lithography is a novel fabrication technique in which a thermosetting polymer is directly drawn from a two-dimensional solid surface without the need for a mask and light irradiation (see figure). Drawing lithography differs from traditional lithography techniques, such as photolithography, in that it is based on the inherently planar geometries of a two-dimensional substrate in a three-dimensional microstructure. [source] Analysis of the solid phase stress tensor in multiphase porous mediaINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 4 2007William G. Gray Abstract Conservation equations for mass, momentum, energy, and entropy are formulated for the phases and interfaces of a three-phase system consisting of a solid and two immiscible fluids. The microscale equations are averaged to the macroscale by integration over a representative elementary volume. Thermodynamic statements for each of the phases and interface entities are also formulated at the microscale and then averaged to the macroscale. This departure from most uses of thermodynamics in macroscale analysis ensures consistency between models and parameters at the two scales. The expressions for the macroscale rates of change of internal energy are obtained by differentiating the derived forms for energy and making use of averaging theorems. These thermodynamic expressions, along with the conservation equations, serve as constraints on the entropy inequality. A linearization of the resulting equations is employed to investigate the theoretical origins of the Biot coefficient that relates the hydrostatic part of the total stress tensor to the normal force applied at the solid surface by the pore fluids. The results here are placed in the context of other formulations and expressions that appear in the literature. Copyright © 2006 John Wiley & Sons, Ltd. [source] Bioinspired Design of a Superoleophobic and Low Adhesive Water/Solid Interface,ADVANCED MATERIALS, Issue 6 2009Mingjie Liu The wetting/antiwetting behavior of liquid droplets on a solid surface is not an apparent or simple contact between two phases, but among three phases. Inspired by the antiwetting behavior of oil droplets on fish scales in water, a superoleophobic and low-adhesive interface is created on a solid substrate with micro/nanohierarchical structures, using oil/water/solid three-phase systems. [source] Reactions of CH3O2 radicals on solid surfaceINTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 11 2004L. A. Manucharova The reaction probability of CH3O2 radicals with NO2, CH4, C3H6, and CH3CHO on the solid surface of KCl in flow at low pressure and temperature range of 297,353 K has been studied. The chosen conditions allowed excluding homogeneous interaction of radicals. The heterogeneous radical decay of peracetic acid served as a source of CH3O2 radicals. On the basis of ESR measurements of CH3O2 radicals with the above-mentioned compounds, a heterogeneous reaction mechanism has been identified. The reactivity of NO2 was greatest for the compounds studied. The effective activation energy was evaluated to be 10.4 ± 0.8 kJ/mol for the reaction of RO2 radicals with NO2 and ,21.3 ± 2.8 kJ/mol for methane. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36: 591,595, 2004 [source] Computational studies of nonadiabatic effects in gas,surface encountersISRAEL JOURNAL OF CHEMISTRY, Issue 1-2 2005Cécile Corriol Model studies are presented, each of which employs a different approach to solving the problem of nonadiabatic dynamics occurring at a solid surface. The jumping wave packet-type approach involving dynamics on two potential energy surfaces punctuated by Franck,Condon transitions was applied to the dynamics of CO desorbed from Ru following energetic electron bombardment. Classical dynamics was also employed in this system to gain a more detailed understanding of the factors important to the final molecular state distribution. To study charge transfer from an alkali-halide surface to a scattering atom, we have used full multi-surface quantum dynamics. A simple, but effective, analysis method was used to make a more detailed connection between the potential energy surfaces and the dynamics. To study the fate of the transferred electron and to model how this depends on substrate and projectile species, we have used a four-dimensional wave packet implementation in which two of the dimensions explicitly account for the electron dynamics. Finally, we consider the famous electron,hole pair excitation problem, from a density functional theory perspective. Spin nonadiabaticity is found to be a new important feature in gas,metal surface interactions. [source] Gas-phase-assisted surface polymerization of methyl methacrylate with Fe(0)/TsCl initiator systemJOURNAL OF APPLIED POLYMER SCIENCE, Issue 3 2007Yoshito Andou Abstract To obtain a high polymer coated Fe(0) surface, gas-phase-assisted surface polymerization (GASP) of methyl methacrylate (MMA) was investigated using a zero-valent iron (Fe(0))/p -toluene sulfonylchloride (TsCl) initiator system, resulting in successful high polymer production on the solid surface. GASP was found to be initiated by radical species that might have been generated via redox reactions with Fe(0), Fe(II), Fe(III), and TsCl. From 1H-NMR analysis, the p -toluene sulfonyl group was found at one end of the polymer chain. The molecular weight of obtained PMMA drastically decreased with increase in the composition ratio of Fe(0) in the initiator system, and increased with increase in polymer yield. From the results, it was assumed that the physically controlled polymerization of MMA proceeded by immobilized active species at gas,solid interfaces. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1879,1886, 2007 [source] Spontaneous segregation on a hybrid chiral surfaceJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 10 2008Szabelski Abstract Segregation of enantiomers in two-dimensional adsorbed layers is a process that is usually controlled by anisotropic directional interactions between adsorbed molecules. In this contribution, we propose a simple theoretical model in which the chiral segregation occurs even though the lateral interactions are neglected. In particular, we consider a solid surface composed of two domains with different patterns of active sites being mirror images of each other. The domains of opposite handedness represent crystal facets of a composite chiral material which are adjoined to form a heterochiral adsorbing surface. To explore equilibrium properties of the system, we use Canonical Ensemble Monte Carlo method for a square lattice. The influence of factors such as energetic properties of the surface and density of the adsorbed layer on the extent of separation is examined. The obtained results indicate that effective two-dimensional separation on the hybrid chiral surface assumed in our model can be achieved only at sufficiently low adsorbate densities. The results also suggest that the segregation on the hybrid surface would be a promising method of enantiodiscrimination for those chiral molecules which do not exhibit strong lateral interactions. © 2008 Wiley Periodicals, Inc. J Comput Chem 2008 [source] An atomization model for splash plate nozzlesAICHE JOURNAL, Issue 4 2010Araz Sarchami Abstract A model for the atomization and spray formation by splash plate nozzles is presented. This model is based on the liquid sheet formation theory due to an oblique impingement of a liquid jet on a solid surface. The continuous liquid sheet formed by the jet impingement is replaced with a set of dispersed droplets. The initial droplet sizes and velocities are determined based on theoretically predicted liquid sheet thickness and velocity. A Lagrangian spray code is used to model the spray dynamics and droplet size distribution further downstream of the nozzle. Results of this model are confirmed by the experimental data on the droplet size distribution across the spray. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Kinetics of microbubble,solid surface interaction and attachmentAICHE JOURNAL, Issue 4 2003Chun Yang Microbubble,solid surface interaction and attachment under the influence of hydrodynamic and physicochemical forces were studied experimentally and theoretically. An impinging-jet technique was developed to measure bubble-attachment flux onto a flat solid surface in an impinging-jet stagnation flow. A video imaging system enables direct observation of the attachment behavior of hydrogen microbubbles onto two different collector surfaces: hydrophilic untreated glass and hydrophobic methylated glass. Experimental results showed that the attachment flux depends on both hydrodynamic flow and electrolyte concentration. A mass-transfer model developed computes bubble-attachment flux, considering hydrodynamic convection, Brownian diffusion, migration under gravitational buoyancy, and DLVO surface forces (that is, van der Waals and electric double-layer forces). At high flow rates, the numerical predictions for attachment rates onto methylated glass generally agreed well with the experimental data. However, a difference exists between theoretical and experimentally determined attachment rates for both untreated and methylated glass when the Reynolds number of the flow is low. Several mechanisms are proposed to account for this discrepancy. [source] Solidification in heat packs: II.AICHE JOURNAL, Issue 2 2003Role of cavitation When the metallic trigger in a commercial heat pack is flexed to initiate solidification, the acceleration of the liquid near the solid surface can cause cavitation and collapse of small vapor bubbles. It is investigated whether such cavitation is responsible for the operation of the metallic trigger in the subcooled sodium acetate solution in a heat pack. Using cavity collapse theory and the results in Part I for the nucleation pressure of a sodium acetate solution, it is shown that cavitation can generate pressures greater than the nucleation pressure of the solution. However, the period of time during which the solution is exposed to such high pressure is not sufficient to lead to nucleation, and hence the metallic trigger does not induce solidification as a result of cavitation. Experimental results, using sonication, tribonucleation, and shock waves, confirm the theoretical findings. [source] Solvent-mediated solid phase transformations of carbamazepine: Effects of simulated intestinal fluid and fasted state simulated intestinal fluidJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 3 2009Paula Lehto Abstract Solvent-mediated transformations of carbamazepine (CBZ) anhydrate form III were investigated in Simulated Intestinal Fluid, a simple USP buffer medium, and in FaSSIF, which contains sodium taurocholate (STC) and lecithin, important surfactants that solubilize lipophilic drugs and lipids in the gastrointestinal tract. Raman spectroscopy (in situ) was utilized to reveal the connection between the changes in solid phase composition and dissolution rate while simultaneously detecting the solid state and the dissolved amount of CBZ. Initial dissolution rate was clearly higher in FaSSIF, while the solid phase data revealed that the crystallization of CBZ dihydrate was inhibited in both the dissolution media, albeit by different mechanisms. In SIF this inhibition was related to extensive needle growth, which impeded medium contact with the solid surface by forming a sterical barrier leading to retarded crystallization rates. Morphological changes from the needle-like dihydrate crystals to plate-like counterparts in FaSSIF, combined with the information that the transformation process was leveled off, evidenced strong hydrogen bonding behavior between the CBZ and STC molecules. These results underline the importance of biologically representative dissolution media in linking the in vitro dissolution results of solids that are capable of hydrate formation to their in vivo dissolution behavior. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:985,996, 2009 [source] Friction reduction in rolling bearing by using polymer additives,LUBRICATION SCIENCE, Issue 8 2009Maria Bercea Abstract The friction torque on the outer ring of a tapered roller bearing has been experimentally measured for a mineral oil (base oil), as well as for samples of the base oil additived with low-density polyethylene. The data show an important reduction of friction by introducing the polymer into the base oil due to the film formed by the adsorption of macromolecular coils on the solid surface. The effectiveness of macromolecular additive contribution to friction behaviour is described in terms of polymer efficiency, which shows maximum values at low polymer concentrations. Copyright © 2009 John Wiley & Sons, Ltd. [source] Self-organized regular surface patterning by pulsed laser ablationPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 3 2009Juergen Reif Abstract The impact of intense ultra short laser pulses on solid surface - as in laser ablation - results in a transient perturbation of the material to a state far from equilibrium. Due to ultrafast relaxation of the transient disorder in a few picoseconds, self-organized surface patterns occur, with a typical feature size at the order of 100 nm or less, similar as observed in ion sputtering and explained by non-linear dynamics models. The feature size of these structures is determined by the deposited energy dose, their shape and orientation crucially depends on the state of polarization of the incident light. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] UV curing behaviors and hydrophilic characteristics of UV curable waterborne hyperbranched aliphatic polyesters,POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 9 2003Anila Asif Abstract A series of waterborne hyperbranched polyesters (WBHPs) endcapped with methacrylic and salt-like groups in different ratios have been investigated as UV curable resins. The kinetic studies of the drying step and UV curing were carried out by FT-IR measurements. The drying of the film of 100,,m thickness was completed in less than 6,hr at 70°C or within 10,hr at 50°C in an oven. The influence of different photoinitiators and their concentrations, extent of unsaturation and acid content of WBHP on final unsaturation conversion was studied. The surface free energy is a critical character, which affects the surface properties of a cured film. So one method based on the measurement of contact angle of a pure liquid on a solid surface was applied to determine the polar and dispersive components of the surface energy of UV cured films. The investigations of surface energy of WBHPs illustrated that those with more acid content and thus higher polar component are more sensitive to water, while those containing less acid content and thus lower polar term are less water sensitive. Moreover, the UV cured films of WBHPs and their blends with commercial waterborne resins (trade name EB 210, EB 2002, EB 11 and IRR 160) have acceptable pendulum hardness varying from 55 to 180,sec. Copyright © 2003 John Wiley & Sons, Ltd. [source] DigesTip: A new device for a rapid and efficient in-solution protein digestionPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 11 2008Roberto Marangoni Dr. Abstract DigesTip is a new device for in-solution protein digestion, based on a patent pending technology, able to immobilize enzymes (trypsin, in this case) on a solid surface, keeping their activity preserved. DigesTip is a standard pipette tip, usable both by human and by robots. Its main performances are: very short digestion time (1,min) and usability with low protein sample concentrations (5,,g/mL). DigesTip obtains a clear signal in MS measurements and its usage rules out several preparative steps. [source] Denaturing and refolding of protein molecules on surfacesPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 11 2007Bryan Holtz Abstract Keeping protein molecules in the active state on a solid surface is essential to protein microarrays and other protein-based biosensors. Here, we show that the 2-D chemical environment controls the refolding of the denatured green fluorescent proteins tethered to solid surfaces. Refolding occurs readily on the repulsive PEG functionalized surface but is inhibited on the attractive ,NH2 functionalized surface. This result shows the critical importance of the 2-D chemical environment in the maintenance and revival of protein activity on surfaces and opens the door to designing 2-D molecular chaperones for protein folding. [source] | |||||||||||||||||||||||||||||||||||||