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91.
Etienne Gaudin Bernard Chevalier Wilfried Hermes Ute Ch. Rodewald Rainer Poettgen 《ChemInform》2009,40(41):no-no
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
92.
顺式二(乙二胺)二硝基合钴(Ⅲ)酒石酸锑盐,Δ-cis-[Co(en)2(NO2)2]2-d-[Sb2(C4H2O6)2]·2H2O,是由酒石酸锑钾对外消旋混合物cis-[Co(en)2(NO2)2]Cl进行拆分的产物。标题化合物(Sb2Co2C16N12O22H40)的晶体结构由衍射方法确定。晶体学参数为:正交晶系,空间群P212121,a=10.033(5), b=13.203(2),c=25.928(7)(),V=3434(2)3,Z=4,Mr=1114.06, Dc=2.156Mgm-3,μ=21.07 mm-1,F(000)=2208, R=0.072,RW=0.084。结构表明,分子由2个Co(Ⅲ)配离子和一个酒石酸锑阴离子及两个水分子组成,阴离子为一双核螯合离子。Sb原子一对孤对电子与其周围四个配位氧原子形成变形三角双锥结构。通过Co和Sb原子对CuKα射线的反常散射效应确定了分子的绝对构型。二个Co(Ⅲ)离子均为Δ构型,酒石酸锑阴离子为R构型。结构分析表明,标题化合物中三点接触离子对在手性识别中起重要作用。 相似文献
93.
L. A. Zemnukhova G. A. Fedorishcheva R. L. Davidovich 《Russian Chemical Bulletin》1996,45(10):2369-2372
Variations of the shape of123Sb NQR lines in phase transitions in a new ionic conductor, potassium pentafluoroantimonite(ui), in the temperature range from 77 to 430 K were studied. The transition from a paraelectric phase to a commensurate phase occurs via incommensurate and commensurate-modulated phases.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2497–2500, October, 1996. 相似文献
94.
Sb doped sol-gel SnO2 single layers (thickness 100 nm) were prepared from alcoholic solution and deposited via a dip coating process on fused silica substrates. The coatings have been sintered at a typical rate of 10–15 cm2/s by CO2 laser irradiation. The laser spot was scanned in one direction at a speed of 15,000 cm/s and the sample was moved in a perpendicular one at a speed up to 250 mm/s. The temperature of the topmost 10 m layer was monitored by a fast pyrometer (s resolution). The following properties of the coatings have been determined: the electrical resistivity , the carrier density n, and mobility , the structure, the thickness, the mesoscopic and micromorphology and the density. The sintering by CO2 laser radiation is mainly a thermal driven process. At T 500°C it allows to obtain coatings with a smaller resistivity (6.8×10–3 cm) than those produced by conventional furnace firing (el2.9×10–2 cm). The results are discussed in terms of particle size and packing density. 相似文献
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96.
L. A. Zemnukhova G. A. Fedorishcheva S. I. Kuznetsov R. L. Davidovich 《Russian Chemical Bulletin》1996,45(2):366-369
Antimony(m) chlorofluoride complexes M2SbCl3F2 (M = Rb, Cs, or NH4) were studied by the121,123Sb NQR method. A temperature range (77–285 K) with anomalous change in the NQR parameters and a second-order phase transition at 250–280 K for (NH4)2SbCl3F2 were found.Translated from Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 382–385, February, 1996 相似文献
97.
The speciation of inorganic Sb(III) and Sb(V) ions in aqueous solution was studied. The adsorption behavior of Sb(III) and Sb(V) ions were investigated as iodo and ammonium pyrollidine dithiocarbamate (APDC) complexes on a column filled with Amberlite XAD-8 resin. Sb(III) and Sb(V) ions were recovered quantitatively and simultaneously from a solution containing 0.8 M NaI and 0.2 M H2SO4 by the XAD-8 column. Sb(III) ions were also adsorbed quantitatively as an APDC complex, but the recovery of the Sb(V)-APDC complex was found to be <10% at pH 5. According to these data, the concentrations of total antimony as Sb(III)+Sb(V) ions and Sb(III) ion were determined with XAD-8/NaI+H2SO4 and XAD-8/APDC systems, respectively. The Sb(V) ion concentration was calculated by subtracting the Sb(III) concentration found with XAD-8/APDC system from the total antimony concentration found with XAD-8/NaI+H2SO4 system. The developed method was applied to determine Sb(III) and Sb(V) ions in samples of artificial seawater and wastewater. 相似文献
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