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61.
Young Jung Kim Huamei Shang Guozhong Cao 《Journal of Sol-Gel Science and Technology》2006,38(1):79-84
This paper reports direct growth of [001] ZnO nanorod arrays on ITO substrate from aqueous solution with electric field assisted
nucleation, followed with thermal annealing. X-ray diffraction analyses revealed that nanorods have wurtzite crystal structure.
The diameter of ZnO nanorods was 60–300 nm and the length was up to 2.5 μm depending on the growth condition. Photoluminescence
spectra showed a broad emission band spreading from 500 to 870 nm, which suggests that ZnO nanorods have a high density of
oxygen interstitials. Low and nonlinear electrical conductivity of ZnO nanorod array was observed, which was ascribed to non-ohmic
contact between top electrode and ZnO nanorods and the low concentration of oxygen vacancies. 相似文献
62.
63.
Coexistence of liquid and solid phases of Bmim-PF6 ionic liquid on mica surfaces at room temperature
In this communication, we report the coexistence of liquid and solid phases of room temperature ionic liquid (IL) [Bmim][PF6] on mica surfaces, observed by tapping mode atomic force microscopy (AFM) in air. Multilayers as well as drop-on-the-layer structures of the ionic liquid are revealed. The solid layers were very stable, and their orientations were affected by the mica lattice, indicating that the ionic liquid undergoes a template-induced ordering process. These results are helpful for advancing the understanding of interfacial structures of ILs on solid surfaces, the analogous structural patterns in both of its solid and liquid phases, and its heterogeneity. 相似文献
64.
超临界流体在有机合成中的应用 总被引:9,自引:0,他引:9
超临界化学反应是一种新型的反应体系,本文对超临界流体在有机合成反应中应用的最新进展进行了综述。 相似文献
65.
Ca(1S0)+CH2Cl2、CHCl3和Ca(3P)+CH2Cl2、CHCl3反应的动态学研究 总被引:1,自引:0,他引:1
The reactions Ca(~1S_0)+ CH_2Cl_2, CHCl_3 and Ca(~3P)+ CH_2Cl_2, CHCl_3 were studied by means of the laser induced fluorescence (LIF). Systematic simulation of the observed LIF spectra revealed that change of the Ca atoms from the ~3p states to the ~1S_0 state brought about a decrease of the fraction of total energy going to the ground state CaCl product vibration and an increase of the fraction of total energy going to the ground state CaCl product rotation. Total cross sections for the reactions of Ca(~1S_0)+CH_(4-n)Cl_n(n=2, 3) and the fraction of the Ca atoms going to the ~3P states in the discharge Ca beam were estimated from the LIF indensity of the CaCl product and total cross sections for the reactions Ca(~3P)+CH_(4-n)Cl_n. They are 0.39±2 nm, 0.45±2 nm, 1.8+0.1%, respectively. 相似文献
66.
Yongqiang Wang Dr. Guozhong Wang Prof. Hongqiang Wang Dr. Changhao Liang Weiping Cai Lide Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(11):3497-3503
Micro/nanoscale magnesium silicate hollow spheres were synthesized by using silica colloidal spheres as a chemical template in one pot. The hollow spherical structure, consisting of well‐separated nanoscale units, was microscale as a whole and could be easily handled in solution. The as‐synthesized magnesium silicate hollow spheres with large specific surface area showed availability for the removal of organic and heavy‐metal ions efficiently from waste water. Importantly, the micro/nanoscale magnesium silicate hollow spheres that had adsorbed organic pollutants could be regenerated by calcination and used repeatedly in pollutant removal. Magnesium silicate hollow spheres synthesized by a scaled‐up chemical template method may have potential applications in removing cationic dyes and heavy‐metal ions from waste water. 相似文献
67.
Anqiang Pan Jun Liu Ji-Guang Zhang Wu Xu Guozhong Cao Zimin Nie Bruce W. Arey Shuquan Liang 《Electrochemistry communications》2010,12(12):1674-1677
Nano-structured Li3V2(PO4)3/carbon composite (Li3V2(PO4)3/C) has been successfully prepared by incorporating the precursor solution into a highly mesoporous carbon with an expanded pore structure. X-ray diffraction analysis, scanning electron microscopy, and transmission electron microscopy were used to characterize the structure of the composites. Li3V2(PO4)3 had particle sizes of < 50 nm and was well dispersed in the carbon matrix. When cycled within a voltage range of 3 to 4.3 V, a Li3V2(PO4)3/C composite delivered a reversible capacity of 122 mA h g? 1 at a 1C rate and maintained a specific discharge capacity of 83 mA h g? 1 at a 32C rate. These results demonstrate that cathodes made from a nano-structured Li3V2(PO4)3 and mesoporous carbon composite material have great potential for use in high-power Li-ion batteries. 相似文献
68.
Zhao H Ge M Zhang Z Wang W Wu G 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,65(3-4):811-817
The interactions between riboflavin (RF) and human and bovine serum albumin (HSA and BSA) were studied by using absorption and fluorescence spectroscopic methods. Intrinsic fluorescence emission spectra of serum albumin in the presence of RF show that the endogenous photosensitizer acts as a quencher. The decrease of fluorescence intensity at about 350 nm is attributed to changes in the environment of the protein fluorophores caused by the ligand. The quenching mechanisms of albumins by RF were discussed. The binding constants and binding site number were obtained at various temperatures. The distance between albumins and RF in the complexes suggests that the primary binding site for RF is close to tryptophan residue (Trp214) of HSA and Trp212 of BSA. The hydration process of albumins has also been discussed. 相似文献
69.
Alexander Shyichuk Irena Shyichuk Guozhong Wu Yosuke Katsumura 《Journal of polymer science. Part A, Polymer chemistry》2001,39(10):1656-1661
The γ-radiation-induced crosslinking of low-density polyethylene over a wide temperature range was studied with a new log–logarithmic scale method for sol–gel analysis. A straight line was always obtained for the plotting of log (sol fraction) against log (dose). Gel points were accurately obtained from the plot intersects, and scission/crosslinking ratios were obtained from the plot slopes via computer simulations with GelSim6 software. The crosslinking and scission yields were determined to be 0.17 and 0.078 mmol/kJ, respectively, at 30 °C, and they increased to 2.3 and 4.4 mmol/kJ, respectively, at 300 °C. The observed regularities are explained by the fact that enhanced macromolecular motion decreases the cage effect on recombination reactions in the polymer. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1656–1661, 2001 相似文献
70.
Guozhong Wu Yosuke Katsumura Hisaaki Kudoh Yosuke Morita Tadao Seguchi 《Journal of polymer science. Part A, Polymer chemistry》1999,37(10):1541-1548
High‐density polyethylene (HDPE) and low‐density polyethylene (LDPE) were irradiated in vacuo at 30–220 and 30–360°C, respectively, with γ‐rays at doses of 10–400 kGy. Temperature dependence of cross‐linking and gas evolution was investigated. It was found that cross‐linking was the predominant process up to 300°C and the gel point decreased smoothly with temperature. The increase of G(x) with temperature was likely attributed to the temperature effect on addition of radicals to the double bonds present in the polymer. Above 300°C, the gel fraction at a given dose decreased remarkably with temperature and turned to zero at 360°C. The molecular weight variation determined with gel permeation chromatography (GPC) indicated the enhanced degradation at 360°C by radiation. G‐values of H2 increased with temperature and varied with dose. The compositions of the C1–C4 hydrocarbons evolved depended on the structures of side branches. Raising the temperature favored the formation of unsaturated hydrocarbons, and the yield of unsaturated relative to saturated hydrocarbons decreased with dose. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1541–1548, 1999 相似文献