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121.
(Me2NH2)[(Ph3Sn)3(MoO4)2], a Triorganotin Molybdate with Layer Structure The reaction of [(Ph3Sn)2MoO4] with (Me2NH2)Cl in an acetonitrile/water mixture leads to the formation of (Me2NH2)[(Ph3Sn)3(MoO4)2] ( 1 ). ( 1 ) crystallizes in the space group Pca21 with a = 1967.0(4), b = 1353.1(2) and c = 2176.6(5) pm. In the crystal structure of 1 Ph3SnO2 bipyramides and MoO4 tetrahedra are linked by corner sharing to give a layer structure. Additionally the layers are connected by O···H···N hydrogen bridges between MoO4 groups and [Me2NH2]+ ions to give a 3D network structure. 相似文献
122.
Bart M. J. M. Suijkerbuijk Duncan M. Tooke Anthony L. Spek Gerard van Koten Robertus J. M. Klein Gebbink Prof. Dr. 《无机化学与普通化学杂志》2007,633(15):2649-2653
A tin(IV) porphyrin was combined with two axial NCN‐pincer platinum(II) fragments by utilizing the oxophilicity of the apical positions on the tin atom and the acidic nature of the NCN‐pincer platinum derived benzoic acid. The solid‐state structure determined by X‐ray crystallography revealed some close contacts between the pincer complexes and the meso‐p‐tolyl subsitutents of the porphyrin. It was shown by 1H NMR spectroscopy that these close contacts were not present in solution and that this compound can potentially act as a novel building block for supramolecular architectures. 相似文献
123.
Dobrochna Matkowska Maciej Gola Marcin ?nie?ek Piotr Cmoch Krzysztof Staliński 《Journal of organometallic chemistry》2007,692(10):2036-2045
A series of triorganotin hydrides and diorganotin dihydrides containing the optically active 2-(4-isopropyl-2-oxazolinyl)-5-phenyl ligand have been characterized by means of the multinuclear low-temperature NMR investigations, the results of which are discussed. In the corresponding organotin hydrides values of the 1J(1H-117/119Sn) couplings appeared to be temperature dependent, supporting an axial/equatorial position of the hydrogen attached to the tin. 相似文献
124.
Santiago Gómez-Ruiz Mariano Fajardo Antonio Otero 《Journal of organometallic chemistry》2007,692(14):3057-3064
The organo-tin compounds, Me2Sn(C5H4R-1)2 (R = Me (1), Pri (2), But (3), SiMe3 (4)) and Me2Sn(C5Me4R-1)2 (R = H (5), SiMe3 (6)), were prepared by the reaction of Me2SnCl2 with the lithium or sodium derivative of the corresponding cyclopentadiene. Compounds 1-6 have been characterized by multinuclear NMR spectroscopy (1H, 13C, 119Sn). In addition the molecular structures of 5 and 6 were determined by single crystal X-ray diffraction studies. The transmetalation reaction of 1-6 with ZrCl4 or [NbCl4(THF)2] gave the corresponding metallocene complexes in high yields. 相似文献
125.
锡氟磷酸盐玻璃(Pglass)具有较低的玻璃化转变温度,在常规聚合物加工温度窗口内具有熔融流动性,是一种新型的无机类聚合物玻璃。本文采用双螺杆挤出机制备了聚丙烯(PP)/Pglass有机聚合物/无机玻璃复合材料,并对其相形貌、界面性能、流动性能、结晶性能、力学性能和热稳定性能进行了研究。结果表明:Pglass以微米级颗粒分散在PP基体中,且两相之间界面明显、相容性较差。Pglass的添加使复合材料的熔体剪切粘度降低。Pglass的存在促进了基体PP的结晶。复合材料的弹性模量随着Pglass含量的增加而增加。Pglass提高了复合材料的热稳定性。 相似文献
126.
A method is described for the determination of total tin in silicate rocks utilizing a graphite furnace atomic absorption spectrometer with a stabilized-temperature platform furnace and Zeeman-effect background correction. The sample is decomposed by lithium metaborate fusion (3 + 1) in graphite crucibles with the melt being dissolved in 7.5% hydrochloric acid. Tin extractions (4 + 1 or 8 + 1) are executed on portions of the acid solutions using a 4% solution of trioctylphosphine oxide in methyl isobutyl ketone (MIBK). Ascorbic acid is added as a reducing agent prior to extraction. A solution of diammonium hydrogenphosphate and magnesium nitrate is used as a matrix modifier in the graphite furnace determination. The limit of detection is > 10 pg, equivalent to > 1 μg l?1 of tin in the MIBK solution or 0.2–0.3 μg g?1 in the rock. The concentration range is linear between 2.5 and 500 μg l?1 tin in solution. The precision, measured as relative standard deviation, is < 20% at the 2.5 μg l?1 level and < 7% at the 10–30 μg l?1 level of tin. Excellent agreement with recommended literature values was found when the method was applied to the international silicate rock standards BCR-1, PCC-1, GSP-1, AGV-1, STM-1, JGb-1 and Mica-Fe. Application was made to the determination of tin in geological core samples with total tin concentrations of the order of 1 μg g?1 or less. 相似文献
127.
128.
杨泉 《理化检验(化学分册)》2006,42(4):274-275
采用钯加抗坏血酸溶液作为基体改进荆,用塞曼效应扣除背景,对消化后的垃圾焚烧废气滤筒直接进行测定。方法的检出限为100pg,线性范围为0.2~4ng,回收率为96.8%~102.0%。 相似文献
129.
Doménech-Carbó A Doménech-Carbó MT Gimeno-Adelantado JV Bosch-Reig F 《Analytical and bioanalytical chemistry》2006,385(8):1552-1561
A solid-state electrochemical application of the H-point standard addition method to the quantification of two depositable
metals A and B, which produce strongly overlapped stripping peaks, is described. The method is based on the mechanical transference
of mixtures of the solid sample plus a selected compound, of a reference depositable metal R, and of known amounts of a reference
material containing A or B, to paraffin-impregnated graphite electrodes. After a reductive deposition step, voltammograms
recorded for those modified electrodes immersed into a suitable electrolyte produce stripping peaks for the oxidation of all
of the metals deposited. Measurement of the currents at selected potentials in overlapping peaks corresponding to the stripping
of A and B permits the quantitation of these metals in the solid sample, while avoiding matrix effects. The method was applied
to the simultaneous determination of Pb and Sn in archaeological glazes using PbCO3 and SnO2 as standards and ZnO as a reference material.
相似文献
130.
Zeta potential studies show that the ATO nanoparticle surface is positively charged in pH range from 2 to 5 without oxalic acid. The addition of oxalic acid brings a charge reversal on the surface of ATO particle in a wide pH range. The interaction of oxalic acid with surface of ATO nanoparticle was studied by FTIR and indicates that the most probable mechanism is the formation of Sn-O-C bonds via the condensation reaction between the oxalic acid and surface hydroxyl groups. TEM, X-ray diffraction and UV-Vis-Near IR spectra were used to characterize the nanocrystalline ATO sol and thin gel film. 相似文献