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951.
Peng X Yao D Pan Y Yu Q Ni S Bian H Huang F Liang H 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,81(1):209-214
Polydatin is a traditional Chinese medicine which shows effective biological activity as antimicrobial and antiviral agent. The secondary structure changes of bovine serum albumin (BSA) were investigated by the methods of Fourier transform infrared spectroscopy (FT-IR), circular dichroism (CD) and Raman spectroscopy. The experimental results indicated that polydatin changed the secondary structure of BSA. The presence of polydatin decreased α-helix content of BSA. The conformations of disulfide bridges and the microenvironment of Tyr, Trp residues were also changed. 相似文献
952.
The donor/acceptor energy mismatch and vibrational coupling strength dependences of interionic vibrational energy transfer kinetics in electrolyte aqueous solutions were investigated with ultrafast multiple-dimensional vibrational spectroscopy. An analytical equation derived from the Fermi's Golden rule that correlates molecular structural parameters and vibrational energy transfer kinetics was found to be able to describe the intermolecular mode specific vibrational energy transfer. Under the assumption of the dipole-dipole approximation, the distance between anions in the aqueous solutions was obtained from the vibrational energy transfer measurements, confirmed with measurements on the corresponding crystalline samples. The result demonstrates that the mode-specific vibrational energy transfer method holds promise as an angstrom molecular ruler. 相似文献
953.
Wang H Qian K Wang K Bian Y Jiang J Gao S 《Chemical communications (Cambridge, England)》2011,47(34):9624-9626
Homoleptic tetrakis[2,3,9,10,16,17,23,24-octa(butyloxy)phthalocyaninato] dysprosium-cadmium quadruple-decker complex 1 was isolated in relatively good yield of 43% from a simple one-pot reaction. This compound represents the first sandwich-type tetrakis(phthalocyaninato) rare earth-cadmium quadruple-decker SMM that has been structurally characterized. 相似文献
954.
Wang H Wang K Bian Y Jiang J Kobayashi N 《Chemical communications (Cambridge, England)》2011,47(24):6879-6881
Two novel mixed (phthalocyaninato)(porphyrinato) rare-earth and cadmium heterometal complexes have been fabricated in one-pot reaction and their sandwich quadruple-decker nature is unambiguously revealed by X-ray single crystal analysis. 相似文献
955.
956.
In this paper, we present a posteriori error analysis for hp finite element approximation of convex optimal control problems. We derive a new quasi-interpolation operator of Clément type and a new quasi-interpolation operator of Scott-Zhang type that preserves homogeneous boundary condition. The Scott-Zhang type quasi-interpolation is suitable for an application in bounding the errors in L2-norm. Then hp a posteriori error estimators are obtained for the coupled state and control approximations. Such estimators can be used to construct reliable adaptive finite elements for the control problems. 相似文献
957.
Zhen Wei Zheng Liu Rongrong Jiang Chaoqing Bian Tao Huang Aishui Yu 《Journal of Solid State Electrochemistry》2010,14(6):1045-1050
TiO2 array film fabricated by potentiostatic anodization of titanium is characterized by X-ray diffraction (XRD), scanning electron
microscopy (SEM), and charge–discharge measurements. The XRD results indicated that the TiO2 array is amorphous, and after calcination at 500 °C, it has the anatase form. The pore size and wall thickness of TiO2 nanotube arrays synthesized at different anodization voltages are highly dependent on the applied voltage. The electrochemical
performance of the prepared TiO2 nanotube array as an electrode material for lithium batteries was evaluated by galvanostatic charge–discharge measurement.
The sample prepared at 20 V shows good cyclability but low discharge capacity of 180 mA h cm−3, while the sample prepared at 80 V has the highest discharge capacity of 340 mA h cm−3. 相似文献
958.
研究KdV方程纯孤立子解的整体渐近性质,证明了N-孤立子解一致收敛到N个单孤立子解的叠加.进而得到了N-孤立子解在L1-范数意义下的渐近结果,并借此阐述了纯孤立子解与一般速降解的差异. 相似文献
959.
XiaoFeng Huang QianBiao Zhao LingYan He Min Hu QiJing Bian Lian Xue YuanHang Zhang 《中国科学:化学(英文版)》2010,53(12):2593-2599
Secondary organic aerosol (SOA) is one of the major components of aerosols in the atmosphere and has not been well understood so far. Due to the complex chemical composition of organic aerosols, the identification of SOA has been a hotspot and difficult issue in the field of aerosol study. This study attempts to quantitatively identify SOA in winter of Shenzhen based on positive matrix factorization (PMF) analysis. Major sources were resolved and SOA was identified subsequently according to the characteristic ion fragments measured by highly time-resolved aerosol mass spectrometer measurement. It showed that in the winter of Shenzhen the average SOA concentration was 9.41 ± 6.33 μg/m3, accounting for 39.9 ± 21.8% of the total organic mass. Compared with primary organic aerosol (POA), the SOA concentrations had no large variation, suggestive of characteristics of regional secondary pollutants. The ratio of SOA/BC had pronounced diurnal variation, similar to that of O x (O3+NO2), indicating SOA formation was significantly controlled by activity of photochemistry in the atmosphere. The most effective period for SOA formation was from 9 am ~3 pm since the SOA/BC ratio increased by 122% during this period. This study provides a new technical method and a new idea for SOA investigation. 相似文献
960.
以锌片为电极芳香醛为底物在酸性条件下电合成呐醇,探讨了电流密度、反应时间、盐酸浓度对产率的影响.最佳反应条件如下:电流密度2.4A/dm2,反应时间60min,盐酸用量(5mL)2mol/L,呐醇的产率范围14%~80%. 相似文献