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991.
Guo C Yin S Huang L Yang L Sato T 《Chemical communications (Cambridge, England)》2011,47(31):8853-8855
Cs(0.32)WO(3) nanorods, synthesized by a designed water controlled-release process, exhibited strong absorption of light in a wide waveband of 800-15,000 nm, quick conversion of photo-energy to local heat and excellent heat rays cutoff character. 相似文献
992.
Li B Cao H Shao J Zheng H Lu Y Yin J Qu M 《Chemical communications (Cambridge, England)》2011,47(11):3159-3161
Incorporation of reduced graphene oxide into β-Ni(OH)(2) presents high performances with specific discharge capacity of 283 mA hg(-1) after 50 cycles in Ni-MH batteries, and 507 mA hg(-1) after 30 cycles in Li ion batteries. 相似文献
993.
The lack of authentic standards limits the quantitative analysis of herbal drugs in biological samples. This present work demonstrated a practicable assay of herbs and their metabolites independent of the availability of authentic standards. A liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) method for the qualitative and quantitative determination of the metabolites after oral administration of Evodiae fructus and Zuojinwan preparation in rat urine has been developed. Urine samples extracted with a protein precipitation procedure were separated on a C(18) column using a mixture of water (containing 0.1% formic acid) and acetonitrile (30:70, v/v) as mobile phase. The detection was performed by MS with electrospray ionization interface in positive selected reaction monitoring (SRM) mode. One urine sample after administration was selected as 'standard'. The method validation was carried out according to a conventional method that was calibrated by authentic standards. The fully validated method was applied to the pharmacokinetic study of the metabolites in rat urine. The results could provide evidence to explain the combination of Coptidis rhizoma and Evodiae fructus in terms of elimination. 相似文献
994.
Tandem mass spectrometry (MS/MS) of intact, noncovalently-bound protein-ligand complexes can yield structural information on the site of ligand binding. Fourier transform ion cyclotron resonance (FT-ICR) top-down MS of the 29 kDa carbonic anhydrase-zinc complex and adenylate kinase bound to adenosine triphosphate (ATP) with collisionally activated dissociation (CAD) and/or electron capture dissociation (ECD) generates product ions that retain the ligand and their identities are consistent with the solution phase structure. Increasing gas phase protein charging from electrospray ionization (ESI) by the addition of supercharging reagents, such as m-nitrobenzyl alcohol and sulfolane, to the protein analyte solution improves the capability of MS/MS to generate holo-product ions. Top-down proteomics for protein sequencing can be enhanced by increasing analyte charging. 相似文献
995.
A sensitive hydrazine sensor has been fabricated using copper oxide nanoparticles modified glassy carbon electrode (GCE) to
form nano-copper oxide/GCE. The nano-copper oxide was electrodeposited on the surface of GCE in CuCl2 solution at −0.4 V and was characterized by Scanning electron microscopy and X-ray diffraction. The prepared modified electrode
showed a good electrocatalytic activity toward oxidation of hydrazine. The electrochemical behavior of hydrazine on nano-copper
oxide/GCE was explored. The oxidative current increased linearly with improving concentration of hydrazine on nano-copper
oxide/GCE from 0.1 to 600 μM and detection limit for hydrazine was evaluated to be 0.03 μM at a signal-to-noise ratio of 3.
The oxidation mechanism of hydrazine on the nano-copper oxide/GCE was also discussed. The fabricated sensor could be used
to determine hydrazine in real water. 相似文献
996.
Quanyi Hao Danni Lei Xiaoming Yin Ming Zhang Shuang Liu Qiuhong Li Libao Chen Taihong Wang 《Journal of Solid State Electrochemistry》2011,15(11-12):2563-2569
Urchin-like nano/micro-structured Fe3O4/C composite has been successfully synthesized using inexpensive starting materials. The urchin-shaped nano/micro-structure consisted of several oriented nanorods. TEM analysis revealed that there is a large number of pores and uniform amorphous carbon distribution at a nanoscale in the nanorods walls. As used in lithium-ion batteries, the mesoporous Fe3O4/C anode delivered a higher reversible capacity of about 830?mAh?g?1 at 0.1?C up to 50 cycles, as well as enhanced high-rate capability compared with urchin-like Fe2O3 and commercial Fe3O4. The improvements can be attributed to the combined effects of the nano/micro-architecture, the porosity, and the ultra-fine carbon matrix, where the three factors would contribute to possess both the merits of nanometer-sized building blocks and micro-sized assemblies and provide high electronic conductivity. It is believed that the results of this study offer new prospects for improving the lithium storage capacity of metal oxides by controlling both architecture and composition. 相似文献
997.
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1000.
The electronic and optical properties of InMO(4) (M = V, Nb, Ta) photocatalysts are studied using first-principles calculations. For all InMO(4), the calculated band gaps are larger than the measured optical gaps, indicating the existence of sub-bandgap transitions. Impurity states and excitons are considered to interpret the characteristic absorption onsets in the measured UV-visible diffuse reflection spectra. The novel visible-light-active water-splitting photocatalytic properties of InMO(4) are related to the sub-bandgap transitions. Correlation between the impurity states and the photocatalytic activities is discussed for InMO(4)via the conventional mechanism of photocatalytic water-splitting on semiconductors. An excitonic mechanism analogous to Photosystem II in plant photosynthesis is also proposed for the photocatalytic water-splitting process on InMO(4). 相似文献