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951.
Hsuan‐Ying Chen Wei‐Yi Lu Yen‐Jen Chen Sodio C. N. Hsu Siou‐Wei Ou Wei‐Te Peng Nai‐Yuan Jheng Yi‐Chun Lai Bo‐Sheng Wu Hsuan Chung Yun Chen Ta‐Chou Huang 《Journal of polymer science. Part A, Polymer chemistry》2013,51(2):327-333
This study synthesized a series of titanium iminophenoxide complexes and investigated their suitability as catalysts for the ring‐opening polymerization of L ‐lactide (L ‐LA) and ε‐caprolactone (CL). Complexes with bidentate ligands demonstrate higher catalytic activity than their tridentate counterparts since the third coordination atom needs to contend with L ‐LA and CL. Differences in the geometric framework of bidentate ligands also influence the catalytic activity. Type II ligands (N, N‐trans form of Ti complex) prevent the coordination of monomers to Ti thereby decreasing the initiation rate. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 相似文献
952.
953.
Sung Ho Yang Woo‐Jae Chung Sean McFarland Seung‐Wuk Lee 《Chemical record (New York, N.Y.)》2013,13(1):43-59
For the last decade, the fabrication of ordered structures of phage has been of great interest as a means of utilizing the outstanding biochemical properties of phage in developing useful materials. Combined with other organic/inorganic substances, it has been demonstrated that phage is a superior building block for fabricating various functional devices, such as the electrode in lithium‐ion batteries, photovoltaic cells, sensors, and cell‐culture supports. Although previous research has expanded the utility of phage when combined with genetic engineering, most improvements in device functionality have relied upon increases in efficiency owing to the compact, more densely packable unit size of phage rather than on the unique properties of the ordered nanostructures themselves. Recently, self‐templating methods, which control both thermodynamic and kinetic factors during the deposition process, have opened up new routes to exploiting the ordered structural properties of hierarchically organized phage architectures. In addition, ordered phage films have exhibited unexpected functional properties, such as structural color and optical filtering. Structural colors or optical filtering from phage films can be used for optical phage‐based sensors, which combine the structural properties of phage with target‐specific binding motifs on the phage‐coat proteins. This self‐templating method may contribute not only to practical applications, but also provide insight into the fundamental study of biomacromolecule assembly in in vivo systems under complicated and dynamic conditions. 相似文献
954.
Turbulent mixed-convection mass transfer in vertical cylinders was measured using a sulfuric acid–copper sulfate electroplating technique. The Grashof numbers ranged from 5.3?×?109 to 6.9?×?1010, the Reynolds numbers ranged from 4,000 to 14,000, and the Schmidt numbers were approximately 2,000. The test results under buoyancy-aided and buoyancy-opposed flow conditions successfully reproduced typical turbulent mixed-convection heat-transfer behavior and agreed well with existing studies performed by Ko et al. and Parlatan et al. Previous studies have used the cylinder diameter as the characteristic length for the buoyancy coefficient; however, this study focused on the influence of the cylinder height on the mixed-convection mass-transfer rates because the height determines the buoyancy. The tests performed for various heights with a fixed diameter or for various diameters with a fixed height demonstrated the influence of the height-to-diameter ratio on the mass-transfer rate, revealing that the height of the cylinder should be considered as a length scale. A new empirical correlation was derived for turbulent mixed-convection mass transfer that includes the influence of the height-to-diameter ratios. 相似文献
955.
Abstract Discrimination of chiral amines by dimethyldiketopyridino-18-crown-6 (1) is studied by free energy peturbation (FEP) and molecular dynamics (MD) methods. 1 has two (S)-chiral centers and discriminates chiral amines through host-guest interactions. The optically active amines in this study are α-(1-naphthyl)ethylamine, methylbenzylamine, cyclohexylethylamine, and sec-butylamine. The trends in binding free energy differences obtained from FEP calculations were in excellent agreement with experimental results obtained in the gas phase. In order to explain the enantioselectivity of the host in terms of the host-guest interactions at the molecular level, we analyzed the structures generated by 10-ns MD simulations of host-guest complexes. The suggested chiral discrimination mechanism, the π-π interaction and the steric repulsion between the guest and the host, was verified by our MD simulation analysis. 相似文献
956.
Dr. Ting‐Jen R. Cheng Shi‐Yun Wang Dr. Wen‐Hsien Wen Dr. Ching‐Yao Su Mengi Lin Wen‐I Huang Dr. Ming‐Tsan Liu Dr. Ho‐Sheng Wu Nung‐Sen Wang Chung‐Kai Cheng Chun‐Lin Chen Dr. Chien‐Tai Ren Dr. Chung‐Yi Wu Prof. Jim‐Min Fang Dr. Yih‐Shyun E. Cheng Prof. Chi‐Huey Wong 《Angewandte Chemie (International ed. in English)》2013,52(1):366-370
957.
Hyori Kim Sunyoung Park Hwa Kyoung Lee Junho Chung 《Experimental & molecular medicine》2013,45(9):e43
We present a bispecific antibody that recognizes an antigen and a hapten and can be applied to various biological assays, including immunoblotting and immunoprecipitation. In immunoblot analysis of serum, an anti-C5 × anti-cotinine bispecific tandem single-chain variable fragment (scFv)-Fc fusion protein and cotinine-conjugated horseradish peroxidase (HRP) generated a clean signal without the high background that was observed in a parallel experiment using HRP-conjugated goat anti-rabbit immunoglobulin G (Fc-specific) antibody. In immunoprecipitation analysis of serum, use of the bispecific tandem scFv-Fc fusion protein and cotinine-crosslinked magnetic beads significantly reduced the amount of protein contaminants compared with a parallel experiment done with protein A agarose beads. In subsequent immunoblot analysis, use of cotinine–HRP as the secondary probe instead of HRP-conjugated goat anti-rabbit IgG (Fc-specific) antibody successfully eliminated the band corresponding to the bispecific tandem scFv-Fc fusion protein. 相似文献
958.
Ling Chen Shing‐Chung Wong Tianxi Liu Xuehong Lu Chaobin He 《Journal of Polymer Science.Polymer Physics》2004,42(14):2759-2768
Fracture properties and deformation mechanisms of nanoclay‐reinforced maleic anhydride‐modified polypropylene (MAPP) were investigated. Elastic–plastic fracture mechanics was employed to characterize the toughness in light of substantial postyield deformation for the reinforced MAPP. Upon introduction of 2.5 wt % clay loading in maleated MAPP, it was observed that tensile strength, modulus, and fracture initiation toughness concomitantly increased substantially. Continued increase in clay loading thereafter only led to stiffening and strengthening effects to the detriment of fracture toughness. A plot of the J‐integral initiation fracture toughness versus the plastic zone size demonstrated that toughening arose from plastic deformation in the reinforced matrix. Careful examination of deformed tensile specimens using small angle X‐ray scattering (SAXS) showed 2.5 wt % clay gave rise to the highest equatorial scattering, which indicates the presence of microvoids in the matrix. The SAXS results were consistent with that shown in subcritically loaded crack‐tip deformation zone using transmission electron microscopy. Thus, both macroscale three‐point bend fracture data and SAXS results led us to consistent findings and conclusions. Further increase in clay loading above 2.5 wt % reduced the scattering the matrix plasticity and thus the fracture toughness. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2759–2768, 2004 相似文献
959.
Sung Yong Park Jae Woo Chung Rodney D. Priestley Seung-Yeop Kwak 《Cellulose (London, England)》2012,19(6):2141-2151
We develop an antimicrobial active robust metal-cellulose nanohybrid by covalent assembly of metal nanoparticles on cellulose fabric using a simple impregnation of thiol-modified cellulose fabric in colloidal silver (Ag) or palladium (Pd) nanoparticle solutions. The combined results of high resolution transmission electron microscopy (HR-TEM), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDXS) and inductively coupled plasma atomic emission spectrometry (ICP-AES) reveal that the nanoparticles are highly loaded and dispersed in the thiol-modified cellulose fabric, and X-ray photoelectron spectroscopy (XPS) analysis reveals that the nanoparticles are immobilized in the fabric by a strong and stable covalent bond with thiol functional group. This robust covalent linkage between the nanoparticles and the fabric leads to a remarkable suppression of the release of metal nanoparticles from the fabric. In addition, the metal-cellulose nanohybrids show high antimicrobial activity in excess of 99.9 % growth inhibition of the microorganism. Thus, we anticipate that our metal-cellulose nanohybrid may not only protect cell damage caused by penetration and fixation of metal nanoparticles into the human body but also act as a sustainable biomedical textile. 相似文献
960.
Sheau‐Long Lee Chung‐Min Yang Kuan‐Jiunn Shieh Xinmiao Liang Hai‐Yan Li 《中国化学会会志》2000,47(6):1247-1249
Better peak shapes and complete separation of amino‐3,5‐dinitro derivatives by (S)‐N‐(2‐naphthyl)alanine derived chiral stationary phase (CSP) is achieved by adding a trace amount of acetic acid in the mobile phase. This method provides an indication of its broad applicability on direct separation of a series of amino‐containing enantiomers on CSP. In addition, the reversed elution order was obtained on its enatiomeric CSP. 相似文献