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81.
Infrared and birefringence measurements are used to characterize the orientational behavior of fumed silica and mica hybrid‐reinforced poly(dimethylsiloxane) composites. Results of equilibrium stress–strain and swelling experiments are also reported and correlated with the orientational data. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 215–222, 2001 相似文献
82.
Investigating the Role of Conformational Effects on Laccase Stability and Hyperactivation under Stress Conditions 下载免费PDF全文
Dr. Valerio Ferrario Dr. Alexey Chernykh Federica Fiorindo Dr. Marina Kolomytseva Dr. Loris Sinigoi Dr. Nina Myasoedova Dr. Diana Fattor Prof. Dr. Cynthia Ebert Prof. Dr. Ludmila Golovleva Prof. Dr. Lucia Gardossi 《Chembiochem : a European journal of chemical biology》2015,16(16):2365-2372
Fungal laccase from Steccherinum ochraceum 1833 displays remarkable stability under different harsh conditions: organic/buffer mixtures, thermal treatment, and microwave radiation. The behavior is particularly significant in the light of the sharp inactivation observed for two different fungal laccases. Laccase from S. ochraceum 1833 also displays hyperactivation under mild thermal treatment (60 °C). Molecular dynamics simulations at 80 °C explained how this laccase retains the geometry of the electron transfer pathway, thereby assuring electron transfer through the copper ions and thus maintaining its catalytic activity at high temperature. Spectroscopic studies revealed that the thermal activation corresponds to specific conformational changes in the protein. The results indicate that this laccase is potentially applicable under denaturing conditions that might be beneficial for the biotransformation of recalcitrant substrates. 相似文献
83.
Stabilization of Telomeric I‐Motif Structures by (2′S)‐2′‐Deoxy‐2′‐C‐Methylcytidine Residues 下载免费PDF全文
Dr. Anna Aviñó María Dellafiore Dr. Raimundo Gargallo Prof. Dr. Carlos González Dr. Adolfo M. Iribarren Dr. Javier Montserrat Prof. Dr. Ramon Eritja 《Chembiochem : a European journal of chemical biology》2017,18(12):1123-1128
G‐quadruplexes and i‐motifs are tetraplex structures present in telomeres and the promoter regions of oncogenes. The possibility of producing nanodevices with pH‐sensitive functions has triggered interest in modified oligonucleotides with improved structural properties. We synthesized C‐rich oligonucleotides carrying conformationally restricted (2′S)‐2′‐deoxy‐2′‐C‐methyl‐cytidine units. The effect of this modified nucleoside on the stability of intramolecular i‐motifs from the vertebrate telomere was investigated by UV, CD, and NMR spectroscopy. The replacement of selected positions of the C‐core with C‐modified residues induced the formation of stable intercalated tetraplexes at near‐neutral pH. This study demonstrates the possibility of enhancing the stability of the i‐motif by chemical modification. 相似文献
84.
Cover Picture: Stabilization of Telomeric I‐Motif Structures by (2′S)‐2′‐Deoxy‐2′‐C‐Methylcytidine Residues (ChemBioChem 12/2017) 下载免费PDF全文
85.
Preparation and properties of pure crystalline perovskite CeFeO3 thin films with vanadium doping 总被引:1,自引:0,他引:1 下载免费PDF全文
Nanxi Lin Lina Huo Haipeng Liu Xiao Fang Shuting Wu Xin Chen Xiaolin Hu Naifeng Zhuang 《Journal of the American Ceramic Society》2017,100(7):2932-2938
Cerium ferrite (CeFeO3) thin films doped with vanadium (V:CeFeO3) were grown on SiO2 quartz glass and <100>‐oriented SrTiO3 (STO) crystal substrates by the radio‐frequency magnetron sputtering method in this study. The effects of crystallization, substrate, and V‐doping on the quality, the magnetic property and the magneto‐optical property of as‐prepared films are investigated. V:CeFeO3 film grown on STO substrate has better crystallinity and has better lattice integrity due to the higher lattice matching between substrate and film. The magnetic hysteresis loop and the magnetic circular dichroism spectra show that the magnetization strength and the magneto‐optical properties of V:CeFeO3 films have the significant anisotropy. Moreover, V‐doping and the stress lead to the change in easy magnetization direction of film. It shows that the perovskite B‐site doping with transition‐metal ion has significant influence on the magnetic and the magneto‐optical properties of CeFeO3 thin films. 相似文献
86.
87.
通过分析金沙县煤炭产业现状,根据循环经济理念,提出通过利用清洁生产工艺,大力发展煤化工,延长煤炭产业链,增加煤炭产业附加值来实现金沙县煤炭产业可持续发展。 相似文献
88.
Selective and pH-Dependent Binding of a Moth Pheromone to a Pheromone-Binding Protein 总被引:1,自引:0,他引:1
Fluorescence and circular dichroism (CD) data suggest that the major pheromone-binding protein (PBP) from the wild silkmoth,
Antheraea polyphemus, ApolPBP1, undergoes a pH-dependent conformational change similar to that previously observed for the PBP from the silkworm
moth, Bombyx mori, BmorPBP. All three constituents of the sex pheromone, E6,Z11-16Ac, E6,Z11-16Ald, and E4,Z9-14Ac, bound to ApolPBP1 with
apparent high affinity at high pH, but reduced binding at low pH when tested individually in a “cold binding assay.” In competitive
assays, however, ApolPBP1 showed considerable preference for the major constituent of the sex pheromone, E6,Z11-16Ac. These
data suggest that specificity of PBPs contributes at least in part to the remarkable selectivity of moth's olfactory system. 相似文献
89.
90.
基于网格重划分技术,采用有限元软件Marc对等通道转角挤压(Equal Channel Angular Pressing,ECAP)进行数值模拟,得到了模具转角φ=90°、ψ=0°以及不同摩擦条件下圆形试样ECAP变形过程的网格、载荷变化以及等效应变分布规律。结果表明:由于剪切变形和外摩擦作用,底部网格产生畸变,出口端部形成半球形;圆形ECAP过程经历开始变形、稳定变形和终了三个阶段,在开始变形阶段载荷急剧增加,进入稳定阶段后变化平稳,但由于摩擦和加工硬化作用载荷继续增加;与无摩擦情况相比,摩擦的存在增加了试样与模具接触的接触面积、载荷值以及变形的不均匀性。此外,试样中心较表面变形更均匀,而中间截面相比头尾变形较为均匀。 相似文献