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551.
552.
553.
T. Lewe D. Naumann G. Nowicki H. Schneider W. Tyrra Th. Gilles K.-F. Tebbe 《无机化学与普通化学杂志》1996,622(12):2009-2015
Syntheses and Properties of Some New Tris(fluorophenyl)antimony and -bismuth Compounds. Crystal Structure of Tris(2,6-difluorophenyl)bismuth (2,6-F2C6H3)3Bi, (2,4,6-F3C6H2)3Bi, and (2,6-F2C6H3)3Sb are prepared via Grignard reactions with BiBr3 and SbBr3, respectively. The syntheses and properties of the new compounds and the crystal structure of (2,6-F2C6H3)3Bi are described. From the reaction of BiBr3 with Ag(OCOC6H3F2) the bismuth benzoate Bi(OCOC6H3F2)3 is formed in 83% yield. Attempts to prepare (2,6-F2C6H3)3Bi by decarboxylation of the bismuth benzoate failed. 相似文献
554.
P.García Casado A. Mendiola I. Rasines 《Journal of Physics and Chemistry of Solids》1985,46(8):921-923
Polycrystalline Gd2MSbO7 (M =Cr,Mn,Fe,In) have been prepared from M2O3 (M = Cr, Fe, In), Mn metal and Sb2O3 at different temperatures above 1470 K. Gd2MSbO7 (M = Cr, Mn,Fe,In) are cubic, pyrochlore-type compounds, space group Fd3̄m (No. 227), Z = 8, a values varying from 10.266 (1) (M = Cr) to 10.486 (1) Å (M = In). For Gd in 16(c), M and Sb at random in 16(d) sites, oxygen atoms in 8(a) and 48(?) positions and x, oxygen positional parameter, equal to 0.412 (M = In) up to 0.425 (M = Mn), origin at center (3̄m), R values from 0.032 (M = In) to 0.041 (M = Mn) are obtained. X-ray powder diffraction data and interatomic distances are given. 相似文献
555.
Bertrand Marrot Chantal Brouca-Cabarrecq Alain Mosset 《Journal of chemical crystallography》1998,28(6):447-452
The synthesis and crystal structure of a new EDTA complex, [CaSb2(EDTA)2(H2O)8]n, are reported. This compound crystallizes in the monoclinic space group P21/n, with a = 7.132(1) Å, b = 21.893(3) Å, c = 10.891(2) Å, = 91.15(2)°. Sb(EDTA) entities are connected through carboxylate bridges to the calcium atoms resulting in layers parallel to the (101) plane. These layers are linked through a weak Sb···O bond (3.171 Å). Pyrolysis of this complex under sulfur vapor, between 400 and 800°C, leads to a mixture of the monometallic sulfides. Pyrolysis in air above 700°C allows the easy preparation of the mixed oxide CaSb2O6. 相似文献
556.
建立滤纸还原-硫酸铈滴定法测定含锑铅精矿中锑含量的方法。采用硫酸、硝酸溶解样品,以滤纸作还原剂,在盐酸介质中,用磷酸掩蔽高价铁,以甲基橙和亚甲基蓝为指示剂,于80~90℃下,用硫酸铈标准溶液滴定至溶液突变至亮蓝色(铁含量高时为黄绿色)为终点。在实验条件下对3个含锑铅精矿样品进行分析,测定结果的相对标准偏差为0.7%~2.2%(n=8),加标回收率为95%~106%。分别采用该方法和锑矿石中锑的国家标准分析方法GB/T 15925-2010对含锑铅精矿样品进行测定,两种方法的测定值基本一致,相对误差为1.4%~4.5%。该方法准确度高,精密度好,成本低,适用于铅精矿中锑含量的测定。 相似文献
557.
Yalan Deng Prof. Ling Huang Xuehua Dong Lei Wang Prof. Kang Min Ok Prof. Hongmei Zeng Prof. Zhien Lin Prof. Guohong Zou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(47):21337-21342
Discovering new functional genes, designing perfect crystal structures, and developing high-performance materials are the goals being pursued by scientists. Herein, the first antimony pyrophosphate, K2Sb(P2O7)F, possessing an optimal layered structure, is reported, where the perfect structural arrangement induces excellent optical properties. K2Sb(P2O7)F not only displays a sharply enhanced birefringence (0.157@546 nm) compared to the existing phosphate optical materials, but also exhibits a strong second-harmonic generation response (4.0×KDP). Remarkably, a new bifunctional gene, the square-pyramidal SbO4F group, was discovered, and a unique two-dimensional arrangement of Cairo pentagonal tiling units was observed in inorganic compounds for the first time. 相似文献
558.
Christoph Helling Dr. Christoph Wölper Dr. George E. Cutsail III Prof. Dr. Gebhard Haberhauer Prof. Dr. Stephan Schulz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(59):13390-13399
Oxidative addition of Cp*SbX2 (X=Cl, Br, I; Cp*=C5Me5) to group 13 diyls LM (M=Al, Ga, In; L=HC[C(Me)N (Dip)]2, Dip=2,6-iPr2C6H3) yields elemental antimony (M=Al) or the corresponding stibanylgallanes [L(X)Ga]Sb(X)Cp* (X=Br 1 , I 2 ) and -indanes [L(X)In]Sb(X)Cp* (X=Cl 5 , Br 6 , I 7 ). 1 and 2 react with a second equivalent of LGa to eliminate decamethyl-1,1’-dihydrofulvalene (Cp*2) and form stibanyl radicals [L(X)Ga]2Sb . (X=Br 3 , I 4 ), whereas analogous reactions of 5 and 6 with LIn selectively yield stibanes [L(X)In]2SbH (X=Cl 8 , Br 9 ) by elimination of 1,2,3,4-tetramethylfulvene. The reactions are proposed to proceed via formation of [L(X)M]2SbCp* as reaction intermediate, which is supported by the isolation of [L(Cl)Ga]2SbCp ( 11 , Cp=C5H5). The reaction mechanism was further studied by computational calculations using two different models. The energy values for the Ga- and the In-substituted model systems showing methyl groups instead of the very bulky Dip units are very similar, and in both cases the same products are expected. Homolytic Sb−C bond cleavage yields van der Waals complexes from the as-formed radicals ([L(Cl)M]2Sb . and Cp* . ), which can be stabilized by hydrogen atom abstraction to give the corresponding hydrides, whereas the direct formation of Sb hydrides starting from [L(Cl)M]2SbCp* via concerted β-H elimination is unlikely. The consideration of the bulky Dip units reveals that the amount of the steric overload in the intermediate I determines the product formation (radical vs. hydride). 相似文献
559.
N. M. Laptash E. V. Kovaleva A. A. Mashkovskii A. Yu. Beloliptsev L. A. Zemnukhova 《Journal of Structural Chemistry》2007,48(5):848-854
Vibrational and 17O NMR spectroscopy in combination with quantum chemical calculations are used to investigate the hydrolysis of antimony(III) fluoride complexes. A hydrolytic decomposition of SbF3 and [SbF4]? is accompanied by oligomerization with the formation of edge-and corner-connected dimers ([Sb2O2F4]2?, [Sb2OF8]4?) and trimers ([Sb3O3F6]3?, [Sb3OF9]2?) with bridging oxygen atoms. The hydrolysis of [SbF4]? is also characterized by the presence in the solution of a discrete cation of [SbF5]2? which is least hydrolized. Only a partial isomorphic substitution of fluoride ion by hydroxide one is possible, which is reflected in the composition of K2Sb(OH)xF5?x (x = 0.3) crystals isolated from the fluoride aqueous solution. 相似文献
560.
Magnetic beads (MBs) are versatile tools in the separation of nucleic acids, proteins and other biomacromolecules, their complexes and cells. In this article recent application of MBs in electrochemical biosensing and particularly in the development of DNA hybridization sensors is reviewed. In these sensors MBs serve not only for separation but also as a platform for optimized DNA hybridization. A hybridization event is detected separately at another surface, which is an electrode. The detection is based either on the intrinsic DNA electroactivity or on various kinds of DNA labeling, including chemical modification, enzyme tags, nanoparticles, electroactive beads, etc., greatly amplifying the signals measured. In addition to DNA hybridization, other kinds of biosensing in combination with MBs, such as DNA-protein interactions, are reviewed. 相似文献