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排序方式: 共有460条查询结果,搜索用时 31 毫秒
1.
2.
Ram C. Maurya Deen D. Mishra Surendra K. Jaiswal Sudipta Mukherjee 《Transition Metal Chemistry》1992,17(5):381-383
Some new low-spin hexacoordinated cyanonitrosyl complexes of Cr1 of the type [Cr(NO)(CN)2(L)2(H2)], where L is an aromatic aldehyde oxime or Mannich base, have been prepared by the interaction or K3[Cr(NO)(CN)5]· H2O with L in aqueous AcOH, and characterized by a range of physico-chemical techniques, I.r. data suggest that all the oxime
derivatives and Mannich bases act as monodentate ligands by coordinating through the aromatic nitrogen.
TMC 2564 相似文献
3.
Sea nodules were extensively studied over a wide range of temperature ranging from 77K to 1175K using Mossbauer effect and
ESR. The Mossbauer studies of the nodules at 77K and room temperature show a quadrupole doublet whereas at higher temperatures
magnetic spectra were obtained starting at around 875K which ultimately gives a hyperfine field of around 390 KOe at 1175
K. The Mossbauer spectra recorded at 30K did not show any significant change in the room temperature spectra. The analysis
of the spectra upto 775K showed two positions of FeR+, vie., octahedral and tetrahedral which were varified by ESR of the diluted samples. 相似文献
4.
Krishna Raman Surendra S. Parmar Shiva P. Singh 《Journal of heterocyclic chemistry》1980,17(5):1137-1139
A series of 1-(5-phenyl-2H-tetrazol-2-ylacetyl)-4-substituted thiosemicarbazids were prepared as possible antiinflammatory agents. Their antiproteolytic activity was reported. 相似文献
5.
Surendra K Krishnaveni NS Reddy MA Nageswar YV Rao KR 《The Journal of organic chemistry》2003,68(5):2058-2059
A mild and efficient oxidation of alcohols with o-iodoxybenzoic acid (IBX) catalyzed by beta-cyclodextrin in a water/acetone mixture (86:14) has been developed. A series of alcohols were oxidized at room temperature in excellent yields. 相似文献
6.
K. Surendra 《Tetrahedron letters》2006,47(13):2133-2136
A new and convenient procedure for the synthesis of homoallylic alcohols directly from aromatic acetals and dioxolanes has been developed with very good yields under biomimetic conditions using a Zn-mediated Barbier-type allylation in the presence of β-cyclodextrin in water. 相似文献
7.
The thermal stability of some boracites, CuB7O13Cl, NiB7O13Br and FeB7O13I, was investigated using thermogravimetry in air up to 1000°, DTA in air to 1200° and evolved gas analysis in vacuum to 1200°C. Only the FeI compound showed weight loss below 1000°C. The endothermic peaks associated with melting were CuCl (1025°C), NiBr (1150°C) and FeI) (965°C). Evolved gas analysis indicated major differences in the decomposition products of the three materials. 相似文献
8.
Boyapati Venkateswara Rao Neelam Palta Surendra N. Dubey Desh M. Puri 《Transition Metal Chemistry》1985,10(2):60-62
Summary Ethylene- ando-phenylene-diamine-N, N-bis(dimethylmethylenephosphonic) acids form polymeric complexes of general formula M2L · xH2O (M = MnII, CoII, NiII, CuII, ZnII, CdII or PbII; x=2 or 4). These have octahedral geometry and are polymeric, according to i.r. (far and near) and electronic spectral data and magnetic moment and thermogravimetric studies. The ligands are thought to be tetradentate for each metal atom, coordination taking place through phosphoryl oxygen and amino-group nitrogen. 相似文献
9.
The urinary codeine-to-morphine ratios in fifteen volunteers administered codeine tablets at intervals were studied by gas chromatography (GC) and compared with one month's GC results for enzyme multiplied immunoassay technique (EMIT)-screened urine specimens in a mass-screening programme for abuse of opiate drugs, particularly heroin. It appears that when M less than 2 and C/M greater than 0 or when M greater than 2 and C/M greater than 0.5, where C and M are codeine and morphine concentrations in micrograms per 10 ml of urine, codeine consumption has to be presumed. 相似文献
10.
1,4-Disubstituted 1,2,3-triazoles are obtained in excellent yields via a three-component coupling of secondary alcohols, alkynes and trimethylsilyl azide (TMSN3). This one-pot reaction occurs through in situ generation of an azide from the alcohol and TMSN3, followed by 1,3-dipolar cycloaddition of the terminal alkyne to afford the corresponding disubstituted triazoles. 相似文献