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排序方式: 共有502条查询结果,搜索用时 15 毫秒
111.
112.
将聚乙烯吡咯烷酮(PVP)在高温高压及KOH溶液中部分开环,得到具有羧基的ORPVP(开环率4%),再将其与胶原蛋白复合并交联制备得到具有自抗炎功能的海绵敷料.研究结果显示,该海绵材料具有均一的多孔结构,可在20s内快速吸水并接近溶胀平衡,保水率达35%;具有良好的自抗炎作用,可将由脂多糖引起的NO炎症因子降低57.1%;能有效促进NIH-3T3细胞增殖,有望在临床伤口修复治疗中得以应用. 相似文献
113.
Qiang Yuan Wei Jiang Huixuan Zhang Jinghua Yin Lijia An R. K. Y. Li 《Journal of Polymer Science.Polymer Physics》2001,39(16):1855-1859
The toughness of high‐density polyethylene (HDPE)/glass‐bead blends containing various glass‐bead contents as a function of temperature was studied. The toughness of the blends was determined from the notch Izod impact test. A sharp brittle–ductile transition was observed in impact strength–interparticle distance (ID) curves at various temperatures. The brittle–ductile transition of HDPE/glass‐bead blends occurred either with reduced ID or with increased temperature. The results indicated that the brittle–ductile‐transition temperature dropped markedly with increasing glass‐bead content. Moreover, the correlation between the critical interparticle distance (IDc) and temperature was obtained. Similar to the IDc of polymer blends with elastomers, the IDc nonlinearly increased with increasing temperature. However, this was the first observation of the variation of the IDc with temperature for polymer blends with rigid particles. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 1855–1859, 2001 相似文献
114.
Dr. Jinghua Li Dr. Lunqiao Xiong Dr. Bing Luo Prof. Dengwei Jing Dr. Jiamei Cao Prof. Junwang Tang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(68):16879-16888
A novel hybrid photocatalyst composed of hollow carbon nanospheres (NCS) and graphitic carbon nitride (CN) curly nanosheets has been prepared by the calcination of a NCS precursor and freeze-dried urea. The optimized photocatalyst exhibits an efficient photocatalytic performance under visible light irradiation with a highest H2 generation rate of 3612.3 μmol g−1 h−1, leading to an apparent quantum yield of 10.04 % at 420 nm, five times higher than the widely reported benchmark photocatalyst CN (2.01 % AQY). The materials characterization shows that NCS-modified CN curly nanosheets can promote photoelectron transfer and suppress charge recombination through their special coupling interface and NCS as an electron acceptor, which significantly improves the photocatalytic efficiency. Thus, this study provides an efficient strategy for the design of highly efficient photocatalyst, particularly suitable for a totally metal-free photocatalytic system. 相似文献
115.
Jinghua Han Da-Yuan Wang Qiuyu Wang Li Meng Zihan Luo Jing Li Yanke Kang Wenhui Lv Qingqing Huang Prof. Dr. Peng George Wang Dr. Yajie Wang Prof. Dr. Jie Shen Prof. Dr. Yanming Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(4):e202103114
We designed, synthesized, and characterized a tri-block copolymer. Its hydrophobic part, a chain of histone deacetylase inhibitor (HDACi) prodrug, was symmetrically flanked by two identical PEG blocks, whereas the built-in HDACi was a linear molecule, terminated with a thiol at one end, and a hydroxyl group at the other. Such a feature facilitated end-to-end linkage of prodrugs through alternatively aligned disulfides and carbonates. The disulfides served dual roles: redox sensors of smart nanomedicine, and warheads of masked HDACi drugs. This approach, carefully designed to benefit both control-release and efficacy, is conceptually novel for optimizing drug units in nanomedicine. Micelles from this designer polyprodrug released only PEG, CO2 and HDACi, and synergized with DOX against HCT116 cells, demonstrating its widespread potential in combination therapy. Our work highlights, for the first time, the unique advantage of thiol-based drug molecules in nanomedicine design. 相似文献
116.
117.
Peng Jiang Jeng-Lung Chen Ferenc Borondics Per-Anders Glans Mark W. West Ching-Lin Chang Miquel Salmeron Jinghua Guo 《Electrochemistry communications》2010,12(6):820-822
A novel electrochemical setup has been developed for soft X-ray absorption studies of the electronic structure of electrode materials during electrochemical cycling. In this communication we illustrate the operation of the cell with a study of the corrosion behavior of copper in aqueous NaHCO3 solution via the electrochemically induced changes of its electronic structure. This development opens the way for in situ investigations of electrochemical processes, photovoltaics, batteries, fuel cells, water splitting, corrosion, electrodeposition, and a variety of important biological processes. 相似文献
118.
Jinghua Yu Bo Li Ping Dai Shenguang Ge Xiaoliang Cheng 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2009,74(4):875-880
In this paper the resonance Rayleigh scattering (RRS) and second-order scattering (SOS) spectrums of interaction between deoxyribonucleic acid (DNA) and 3-(4′-methylphenyl)-5-(2′-sulfophenylazo) rhodanine (4MRASP) in the environment of surface active substance sodium dodecyl sulfate (SDS) were reported. The light scattering intensity of 4MRASP was enhanced obviously and directly proportional to the concentrations of DNA when DNA was present. Based on this, two new determination methods of DNA were established with high sensitivity and selectivity, and the limits of detection were 8.00 and 1.07 ng mL−1. They were applied to the determination of trace amounts of nucleic acid in synthetic and practical samples with satisfactory results. At last, the active mechanism among molecules was studied by ultraviolet spectrum, scattering spectrum and thermodynamics, which showed that the active force was changed from hydrophobic force to electrostatic force before and after SDS was added, and the mechanism of sensitization effect of SDS was proposed. 相似文献
119.
In this paper, we calculate Edgeworth expansion of a test statistic on independence when some of the parameters are large, and simulate the goodness of fit of its approximation. We also calculate an error bound for Edgeworth expansion. Some tables of the error bound are given, which show that the derived bound is sufficiently small for practical use. 相似文献
120.
In this paper, a vector parameter method for ridge regression is proposed. We choose the negative gradient of mean square error as vector direction and decide vector norm with the expectation constrains both of mean square error and of residual error. We come to conclusions that the mean square error is a decreasing function of vector norm while the residual error a increasing one. It is the monotonicity of the errors that leads to our expectation constrains. Since two conflict constrains are under consideration, our vector parameter ridge regression is expected to bear both satisfactory mean square error and acceptable residual error. Finally, a multi-collinearity model is given as an example. 相似文献