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961.
Debao Wang Yanhong Zhou Caixia Song 《Journal of Dispersion Science and Technology》2013,34(3):336-339
Mono-dispersed oxide and hydroxide nanoparticles have been synthesized through the solvothermal process in alcohol-water mixtures. The products were characterized by powder x-ray diffraction (XRD) and scanning electron microscopy (SEM). Plate-like nanoparticles are obtained for Bi2O2.33, Fe2O3, and Cd(OH)2, and spherical nanoparticles are obtained for SnO2. The growth mechanism for the mono-dispersed nanoparticles has been preliminarily discussed. 相似文献
962.
Yu Liu Lei Zhao Wentao Li Dongyu Zhao Miao Song Yongliang Yang 《Journal of computational chemistry》2013,34(1):67-75
The accurate prediction of protein–ligand binding is of great importance for rational drug design. We present herein a novel docking algorithm called as FIPSDock, which implements a variant of the Fully Informed Particle Swarm (FIPS) optimization method and adopts the newly developed energy function of AutoDock 4.20 suite for solving flexible protein–ligand docking problems. The search ability and docking accuracy of FIPSDock were first evaluated by multiple cognate docking experiments. In a benchmarking test for 77 protein/ligand complex structures derived from GOLD benchmark set, FIPSDock has obtained a successful predicting rate of 93.5% and outperformed a few docking programs including particle swarm optimization (PSO)@AutoDock, SODOCK, AutoDock, DOCK, Glide, GOLD, FlexX, Surflex, and MolDock. More importantly, FIPSDock was evaluated against PSO@AutoDock, SODOCK, and AutoDock 4.20 suite by cross‐docking experiments of 74 protein–ligand complexes among eight protein targets (CDK2, ESR1, F2, MAPK14, MMP8, MMP13, PDE4B, and PDE5A) derived from Sutherland‐crossdock‐set. Remarkably, FIPSDock is superior to PSO@AutoDock, SODOCK, and AutoDock in seven out of eight cross‐docking experiments. The results reveal that FIPS algorithm might be more suitable than the conventional genetic algorithm‐based algorithms in dealing with highly flexible docking problems. © 2012 Wiley Periodicals, Inc. 相似文献
963.
Dongmei Wang Xiaojiao Song Yin Duan Liang Xu Jing Zhou Hongquan Duan 《Electrophoresis》2013,34(9-10):1339-1342
Polystyrene (PS) nanoparticles coated by BSA, hereafter denoted as PS/BSA, were prepared and chemically immobilized for the first time onto a capillary inner wall for open‐tubular CEC (OTCEC). EOF and scanning electron micrography were used to characterize the prepared nanoparticle‐coated capillaries. To investigate the performance of the prepared columns in OTCEC, chiral separation of d ,l ‐tryptophan (dl ‐Trp) was performed in monolayer BSA‐modified capillary and PS/BSA nanoparticle‐coated columns. The results indicated that the nanoparticle‐modified column afforded a higher resolution compared with the monolayer type. Rapid enantioseparation of dl ‐Trp (within 3 min) was achieved with the PS/BSA‐immobilized column using an electroosmotic pump‐assisted CEC. Enantiomer separations of other compounds like dl ‐tyrosine and warfarin were also achieved with the column. Besides, run‐to‐run and column‐to‐column repeatabilities of the PS/BSA‐coated column in the chiral separation were systematically introduced. 相似文献
964.
The interactions between potassium perfluorooctanesulfonate (PFOS) and bovine serum albumin (BSA) were studied by fluorescence spectroscopy. The association constants between PFOS and BSA were obtained by fluorescence enhancing and fluorescence quenching respectively. Furthermore, fluorescence quenching was studied at different temperatures, and the binding constant was also determined by the method of fluorescence quenching. According to the thermodynamic parameters, the main binding force could be judged. The experimental results revealed that BSA and PFOS had strong interactions. The mechanism of quenching belonged to dynamic quenching and the main sort of binding force was hydrophobic force. IR-spectra proved the interaction changed the conformation of BSA. 相似文献
965.
Song Wang Liqiang Tan Jinlong Jiang Jing Chen Liangdong Feng 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):1305-1312
In this research TiO2 sample was synthesized by a simple sol–gel method and was characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM) and Brunauer–Emmett–Teller (BET) techniques. The XRD result indicated that the obtained product was anatase titanium dioxide with high purity, the TEM image clearly showed that the particle sizes of TiO2 nanoparticles were in the range of 30–70 nm, and the measured BET surface area of the heated TiO2 nanoparticles was 147.14 m2/g. In this work, the prepared TiO2 sample was used as a new adsorbent for the adsorption of radionuclide Co(II) ions from aqueous solutions, and the influence of pH, contact time, ionic strength and temperature in the presence or absence of humic acid/fulvic acid (HA/FA) were also investigated. The experimental results indicated that the adsorption of Co(II) ions onto TiO2 was strongly pH-dependent. Based on the surface complexation, the presence of HSs enhanced the adsorption of Co(II) ions and the influence of Co(II) adsorption onto FA–TiO2 hybrids was much stronger than that of HA–TiO2 at pH values of 2.0–9.0. Adsorption of Co(II) ions onto TiO2 powder was strongly dependent on ionic strength. The adsorption process mainly occured in the first contact time of 2 h and could be fitted by a pseudo-second-order rate model. The calculated thermodynamic data indicated that the adsorption of Co(II) ions onto TiO2 was a spontaneous process and favorable at high temperatures. 相似文献
966.
Micelle diffusion coefficient of SDS with different micelle shape in aqueous and water-ethanol solutions are determined by cyclic voltammetry without any probe. The diffusion coefficient decreases with as increasing SDS concentration. The first critical micellar concentration is 8.0xl03, mol 11.corresponding to the transformation from premicelle to spherical micelle. The second critical micellar concentration is 5.60x102and corresponding to transformation from spherical micelle to rod-like micelle. The less the weight ratio of SDS to ethanol is, the larger the diffusion coefficient is. The influence of added water to the micelle solution is almost the same for SDS-ethanol-HaO system with different micelle shape. Mechanism of electrochemical reaction for SDS at platinum electrode is discussed as well. 相似文献
967.
Tianqing Liu Yinyin Gan Lilia Song Jing Qiu Liuhua Chen 《Journal of Dispersion Science and Technology》2013,34(10):1370-1375
Vesicles have been prepared at a constant molar ratio of L-glutamic acid/1-aminodecane/ibuprofen/H2O. The fusion dynamics of the vesicles have been directly observed and followed by using optical microscopy and freeze fracture replication-electron microscopy technologies. With time increasing up to 25 minutes, the vesicles slowly fuse to form large stable vesicles. A membrane phase transition temperature is detected at 97°C. 相似文献
968.
Bin Xie Xue‐Song Feng Chun‐Xiao Zhang Xian‐Cheng Zeng 《Journal of Dispersion Science and Technology》2013,34(6):920-926
Two Schiff base transitional metal complexes bearing morpholine side chains were synthesized and characterized, and were used as a simulative hydrolase in the catalytic hydrolysis of p‐nitrophenyl picolinate (PNPP) in this article. A mechanism of PNPP catalytic hydrolysis in the Brij35 micellar solution was proposed and supported by the results of the spectral analysis and the kinetic calculation. The kinetic model of PNPP catalytic hydrolysis was studied. The some kinetic and the thermodynamic constants on the catalytic reaction were calculated. The results of the study show that the metallomicelle made up of the Schiff base transitional metal complexes and Brij35 micelle revealed a good catalytic activity in PNPP catalytic hydrolysis; the rate of the PNPP catalytic hydrolysis is increased following the increase of the pH values in the buffer solution and affected by the polarization action of metal ion of complex. 相似文献
969.
This articles studied and determined the viscosities of the binary mixtures of water–methanol, water–ethanol, water–propanol, water–acetone, acetone–ethanol, methanol–ethanol, and acetone–hexane and the ternary mixtures of water–methanol–ethanol and water–ethanol–acetone at 20°C. It is shown that the mixing of water with the alcohols and acetone resulted in a positive deviation of viscosity, which reached the maximum value at the water mole fraction x 1 ~ 0.7 for water–methanol, x 1 ~ 0.72 for water–ethanol, x 1 ~ 0.74 for water–propanol, and x 1 ~ 0.83 for water–acetone binary mixture. This viscosity deviation can be mainly attributed to the formation of micelles of alcohol or acetone molecules in water because of the hydrophobic attraction between the hydrocarbon chains. The micelle surfaces are surrounded by hydration layers, leading to the positive viscosity deviation in the liquid mixtures because the water in hydration layers has a much higher viscosity than bulk water. Also, the contrary observation was found in the binary mixtures of acetone–ethanol and acetone–hexane, having a negative viscosity deviation. 相似文献
970.
Li-cheng Wang Hong-yan Wang Yang-wen Zhu Xin-wang Song Shu-juan Liu Xia Liu 《Journal of Dispersion Science and Technology》2013,34(3):374-379
This article aims to compare the interfacial activities of different kinds of surfactants in the same oil/water system. The anionic surfactants of alkylbenzene sulfonates, the polyoxyethylenated nonionic surfactants, the cationic surfactants of alkyl trimethyl ammonium chlorides, and the zwitterionic surfactants of alkyl hydroxyl sulfobetaines were used, and the interfacial tensions of the surfactant solutions against kerosene at different NaCl concentrations were measured. It is found that the interfacial activities of the alkylbenzene sulfonates are high and ultralow interfacial tensions (<0.01 mN/m) can be obtained at proper salinities. While, the nonionic surfactants have relatively low interfacial activities and the minimum tensions are around 0.01 mN/ms. The salinity scanning curves of the alkylbenzene sulfonates and nonionic surfactants decrease first, then increase, showing their interfacial activities can be changed by the salinity effectively. The cationic and zwitterionic surfactants have very low interfacial activities, of which all the tensions are higher than 0.1 mN/ms and are hard to be changed by the salinity. The experimental results may have important reference values for enhanced oil recovery. 相似文献