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991.
Metal Ions Extraction with Glucose Derivatives as Chelating Reagents in Supercritical Carbon Dioxide
Guo Chen YANG Hai Jian YANG 《中国化学快报》2006,17(11):1489-1492
A series of glucose derivatives have been used as chelating reagents to extract metal ions in supercritical carbon dioxide. With perfluoro-1-octanesulfonic acid tetraethylammonium salt as additive, glucose derivatives were selective for Sr2 and Pb2 extraction in supercritical carbon dioxide. 相似文献
992.
A new method has been develoed for fabrication of copper micro-pattern by selective chemical copper deposition based on photolithographed (3-mercaptopropyl)-trimethoxysilane (MPTS) self-assembly monolayers (SAMs). As confirmed by scanning electron microscopy (SEM), Cu closely replicated the mask features. The present approach makes this technic to be cheap and may be applicable to assembly of microelectronic circuits. 相似文献
993.
KNaY-zeolite catalyzed dehydration of methyl lactate 总被引:1,自引:0,他引:1
Hai Feng Shi Yao Chi Hu Yang Wang He Huang 《中国化学快报》2007,18(4):476-478
A promising catalyst,KNaY was prepared by an ion exchange method with aqueous potassium chloride solution.Comparedwith NaY,KNaY was an effective catalyst for the dehydration of methyl lactate to methyl acrylate.Under the optimized conditions,an improved yield of 37.9 mol%was achieved. 相似文献
994.
The materials used to prepare the certified reference materials (CRMs) for Cd rice flour described here were taken from Cd-contaminated rice samples, round-grained and non-sticky rice grown in different provinces throughout China. The Cd rice materials were first blown to remove dust and husk, and then were successively ground, sieved, dried and mixed to form homogeneous rice flour. The Cd rice flour was packed in glass bottles, each bottle containing 40 g. All bottled CRMs were subjected to 60Co radiation (2.5 megarads) for long-term preservation. Atomic absorption spectrometry was used to determine the homogeneity of the cadmium content in each material. The certification of the cadmium content for the three CRMs was performed using isotope dilution mass spectrometry. 相似文献
995.
996.
997.
MingXiaLI HaiTaoYU HongGangFU ZeShengLI JiaZhongSUN 《中国化学快报》2004,15(2):250-252
Three new isomers of FCH2CP system, F(H)CCPH (1), F-cCPC-H(H) (2) and F-cCC(H)P-H (3), are predicted by means of B3LYP and CCSD(T) (single-point) methods with 6-311 G(d,p) and 6-311 G(2df,2p) basis sets, respectively. The three calculated isomers can isomerize into thermodynamically the most stable species F-cPC(H)C-H, which has been suggested in previous theoretical studies, with relatively higher reaction barriers. In view of their higher thermodynamic and kinetic stability, we believe that the three species can be detected in future experiments. 相似文献
998.
999.
Fenghua Li Guanghua Zhao Hongxing Wu Shourong Zhu Huakuan Lin Hai Lin 《Transition Metal Chemistry》2006,31(5):630-638
Five new tridentate ligands and their corresponding La(III) complexes, [La(III)(L)2(H2O)n](ClO4)3 where n = 2,3 and 4; L is N-methyl-1,10-phenanthroline-2-methyleneamine (L1), N-ethyl-1,10-phenanthroline-2-methyleneamine (L2), N-propyl-1,10-phenanthroline-2-methyleneamine (L3), N-n-butyl-1,10-Phenanthroline-2-methyleneamine (L4), and N-benzyl-1,10-phenanthroline-2-methyleneamine (L5), have been synthesized, and characterized by elemental analysis, IR, far-IR, 1H-NMR, thermal gravity analysis and conductance measurement. The interaction of the lanthanum(III) complexes with calf thymus
DNA was studied by means of UV, fluorescence, CD and viscosity measurements. Using ethidium bromide as a fluorescence probe,
the binding mode of the complexes with calf thymus DNA was studied spectroscopically. All the results suggest that the complexes
perhaps interact with calf thymus DNA by intercalative and coordination binding mode. 相似文献
1000.