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891.
Zheng S Huang W Gao N Cui R Zhang M Zhao X 《Chemical communications (Cambridge, England)》2011,47(24):6969-6971
One pot asymmetrical double allylations of sodium sulfide catalyzed by an iridium complex along with a combination of caesium fluoride and water in dichloromethane have been realized and the double allylation products with two C-S bond chiral centers were obtained in 67-99% yields with b/l 81/19-99/1, dr 85/15-99/1, and 96-99% ee. 相似文献
892.
Sun Z Wang Y Wei Y Liu R Zhu H Cui Y Zhao Y Gao X 《Chemical communications (Cambridge, England)》2011,47(43):11960-11962
Silver cluster-aptamer hybrids were mineralized via an artificially designed aptamer. The hybrids gave red emission when excited by light, and they successfully targeted the nucleus of live cells. This method is an effective approach to make cell target probes. 相似文献
893.
Highly stable covalently attached multilayer films were constructed by visible-light irradiation of hydrogen-bonding directed multilayer films of poly(allylamine) and poly(4-vinylphenol). 相似文献
894.
We report a new reducing agent system: hydriodic acid with trifluoroacetic acid, which can chemically convert graphene oxide into reduced graphene oxide at temperatures below 0 °C in solution. This is the first achievement to produce reduced graphene oxide at subzero temperature with a mass production. 相似文献
895.
Dong S Chen X Zhang K Gu L Zhang L Zhou X Li L Liu Z Han P Xu H Yao J Zhang C Zhang X Shang C Cui G Chen L 《Chemical communications (Cambridge, England)》2011,47(40):11291-11293
Molybdenum nitride/nitrogen-doped graphene nanosheets (MoN/NGS) are synthesized and used as an alternative O(2) electrode for Li-O(2) batteries. In comparison with electrocatalysts proposed previously, this hybrid cathode exhibits a high discharge potential (around 3.1 V) and a considerable specific capacity (1490 mA h g(-1), based on carbon + electrocatalyst). 相似文献
896.
X. X. Han X. M. Jiang Z. G. Cui J. W. Yan J. G. Liu 《Journal of Thermal Analysis and Calorimetry》2011,104(2):771-779
For obtaining high shale oil yield as well as treating shale char efficiently and in an environmentally friendly way in a
new comprehensive utilization system of oil shale, a series of fundamental experiments have been conducted for exploring the
effects of retorting factors on shale oil yield and shale char characteristics. Based on these previous studies, in this article,
combustion experiments of shale chars obtained under various retorting conditions were performed with a Q5000IR thermogravimetric
analyzer and a Leitz II-A heatable stage microscope and the effects of retorting factors were discussed on the combustion
characteristics of shale char. Among four studied retorting parameters, retorting temperature and residence time exert very
significant influence on the combustion characteristics of shale char. Either elevating the retorting temperature from 430
to 520 °C or lengthening the residence time at a low retorting temperature will largely decrease residual organic matters
within shale char, resulting in decreasing mass loss in the low-temperature stage of combustion process of shale char, an
elevation of ignition temperature and a shift of ignition mechanism from homogeneous to heterogeneous. One set of retorting
condition was also recommended as a reference for designing the comprehensive utilization system of oil shale studied in this
work: retort temperature of 460–490 °C, residence time of 20–40 min, particle size of <3 mm, and low heating rate of <10 °C/min. 相似文献
897.
898.
In this paper, microwave-assisted extraction (MAE) of oxymatrine from Sophora flavescens were studied by HPLC-photodiode array detection. Effects of several experimental parameters, such as concentration of extraction solvent, ratio of liquid to material, microwave power, extraction temperature, and extraction time on the extraction efficiencies of oxymatrine were evaluated. The optimal extraction conditions were 60% ethanol, a 20:1 (v/v) ratio of liquid to material and extraction for 10 min at 50 °C under 500 W microwave irradiation. Under the optimum conditions, the yield of oxymatrine was 14.37 mg/g. The crude extract obtained could be used as either a component of some complex traditional medicines or for further isolation and purification of bioactive compounds. The results, which indicated that MAE is a very useful tool for the extraction of important phytochemicals from plant materials, should prove helpful for the full utilization of Sophora flavescens. 相似文献
899.
900.