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YUAN Zhi-Qing a Lü Guang-Lie a② WEI Fan-Song b LEI Yong-Quan b a 《结构化学》2004,23(5):520-524
Crystal structures of nonstoichiometric La(Ni, Sn)5 x (x = 0.1~0.4) alloysprepared by different methods were investigated by using powder X-ray diffraction and Rietveldrefinement analysis. Space group of this type of alloys belongs to P6/mmm, in which Sn onlyoccupies the 3g sites. It has been demonstrated that some of the la sites of the nonstoichiometricalloy are replaced by the Ni-Ni dumb-bells which have a strong correlation with the anisotropicthermal parameter B33. The preparation methods have an effect on the number of dumb-bells thatcan substitute the l a sites. It was found that the annealed alloys have more Ni-Ni dumb-bells inthe structure than the rapid solidified and as-cast alloys have while still keep good crystallinity. 相似文献
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COOEtCOCH3(CH3)2NNHNH2NNCH3OOEtNH2NH2NNCH3ONHNH2PhNCSNNCH3ONHNHCNHSOH-NNCH3NNHNPhS12345 1 INTRODUCTION A large number of 1,2,4-triazole derivatives have been synthesized in recent years[1~4]. Many of them are reported to exhibit broad spectrum biologi-… 相似文献
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GAO Yong-Guangb MU Chu-Chunb LI Xin-Shenga b② XU Dong-Chenga b SU Honga WEN Yi-Hanga b a 《结构化学》2008,27(6):663-666
The title compound 2-phenyl,5,6,7,8-tetrahydro-6,6-dimethyl-5,7-methano-8- quinolinol 1 has been synthesized by the oxidation of corresponding anion with 02. The oxidation gave a convenient method for synthesizing pyridylalcohol 1 in good yield. The suitable single crystals for X-ray diffraction were obtained by recrystallization from a mixture of solvents (ether and ethyl acetate). The configuration of C6 in the title compound is in R form and there are strong face-to-face offset π-π interactions between pyridine rings. Crystallographic data for 1: C18H19NO, Mr = 265.34, monoclinic, space group P21/c with a = 13,4073(4), b = 10.2866(3), c = 10,5570(3)A, β = 108.413(2)°, V = 1381.43(7) A^3, Z = 4, De= 1.276 g/cm^3, μ = 0.078 mml, F(000) = 568, R = 0.0721 and wR = 0.2054 for 2241 observed reflections (I〉 2σ(I)). 相似文献
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1 INTRODUCTION Due to their variability in binding modes, five- membered heterocyclic ligands such as pyrazole[1] and 1,2,4-triazole[2] have been drawn much attention. Consequently, there are numerous reports on their derivatives. Imidazoles resemble pyrazoles, and they are isomeric five-membered heterocyclic molecules containing two nitrogen atoms. Furthermore, imida- zole is also a ring component of adenine and purine, one of the most versatile binding sites in biological systems, so th… 相似文献
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1 INTRODUCTION The cadmium(??) complexes have been exten-sively studied because of their potentially usefulproperties, such as toxicity research[1], catalysis[2],magnetism[3] and nonlinear optics[4]. A lot of studieson binuclear cadmium(??) pendant-ar… 相似文献
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Reinvestigation on the Reaction of Salicylic Chloride with Salicylic Amide and X-ray Crystal Structure of a New Macrocyclic Polyester 总被引:1,自引:0,他引:1
DU Da-Ming② CHEN Xiao HUA Wen-Ting JIN Xiang-Lin 《结构化学》2003,22(5):512-516
1 INTRODUCTION In the systematic studies on the synthesis, structure and recognition of macrocyclic phospho- ramidate containing biaryl oxadiazole[1, 2], we need to synthesize benzoxazines. Lattmann reported that the salicylic chloride reacts with salicylic amide at 170℃ to give 2-(2-hydroxyphenyl)benzo[1,3]- oxazine-4-one[3]. However, Palazzo got bisamide 1 in 90% yield under similar conditions[4]. Titherley reported that amides of type 1 underwent cycli- zation to benzoxazines if hea… 相似文献
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YANG Da-Sen DAI You-Zhi ② LI Jian-Hua ZHU Fei 《结构化学》2006,25(10):1183-1188
1 INTRODUCTION Chlorophenols (CPs) have been widely applied in such industries[1] as wood preservative, antitrust, bactericide and herbicide since 1930s. Due to the existence of phenol ring structure and chloro-atom, chlorophenols have strong toxicity and high anti- degradation ability. Previous reports show that[2, 3] chlorophenols are difficult to oxidize under aerobic condition, whereas anaerobic biological treatment can effectively reduce the toxicity towards microor- ganism so as to … 相似文献
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1 INTRODUCTION The chelate ligand phenanthroline (phen) and its derivatives have played an important role in the development of coordination chemistry[1~6]. In the last few years, the synthesis and reaction mechanism of 2-hydroxyl-phenanthroline (HOphen) complexes, in particular, attract much attention due to their unusual “anomalies”. Gillrad[7] proposed the mecha- nism about this kind of reaction as follows: nucleo- philic -OH or H2O attacking α-C of coordinated he- terocyclic lig… 相似文献