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41.
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合成了锑-镨与乙二胺四乙酸形成的新颖三维配合物[Sb2-μ4-(EDTA)2Pr(H2O)5]NO3•4H2O, 用元素分析、红外光谱、热分析及X射线单晶衍射法等进行了组成和结构表征. 结果表明该配合物属正交晶系, 空间群Pnn2; 晶胞参数: a=1.07031(2) nm, b=2.30805(4) nm, c=0.72343(2) nm, V=1.78711(7) nm3, Z=2, Dc=2.202 g/cm3, F(000)=1164, μ=2.955 mm-1, GOF=1.000, 最终偏离因子R1=0.0203, wR2=0.0545 [I>2σ(I)]. 在标题化合物中, 每个镨(III)离子的配位数为9, 与五个水分子中的五个氧原子和四个羧基氧原子配位, 形成三帽三角棱柱空间配位多面体. 锑(III)与EDTA离子中的四个氧原子和两个氮原子配位, 在赤道平面上有一孤对电子. 同时讨论了配合物的热分解过程. 相似文献
43.
通过样品处理、谱线选择、准确度和精密度测定、加标回收实验及与其他测定方法的比对实验,建立了电感耦合等离子体原子发射光谱法(ICP-AES)测定粗锑中As、Bi、Cd 、Cu、Fe、Pb、Se 7种元素的定量分析方法。实验结果表明,该方法准确度高,稳定可靠,相对标准偏差(RSD,n=6)均小于3%,方法的加标回收率在95~105%之间,分析结果与分光光度法、原子吸收光谱法(AAS)及原子荧光光谱法(AFS)分析结果相吻合,能够满足日常对粗锑中杂质元素含量测定的要求。 相似文献
44.
Vanessa A. Béland Zhiqiang Wang Prof. Tsun‐Kong Sham Prof. Paul J. Ragogna 《Angewandte Chemie (International ed. in English)》2018,57(40):13252-13256
The synthesis of phosphane‐ene photopolymer networks, where the networks are composed of crosslinked tertiary alkyl phosphines are reported. Taking advantage of the rich coordination chemistry of alkyl phosphines, stibino‐phosphonium and stibino‐bis(phosphonium) functionalized polymer networks could be generated. Small‐molecule stibino‐phosphonium and stibino‐bis(phosphonium) compounds have been well characterized previously and were used as models for spectroscopic comparison to the macromolecular analogues by NMR and XANES spectroscopy. This work reveals that the physical and electronic properties of the materials can be tuned depending on the type of coordination environment. These materials can be used as ceramic precursors, where the Sb‐functionalized polymers influence the composition of the resulting ceramic. 相似文献
45.
氢化物发生-原子荧光光谱法是土壤环境中锑检测所广泛使用的方法.土壤的消解前处理分别采用王水微波消解(半消解)、混酸全消解(硝酸+高氯酸+氢氟酸)方式.研究结果表明王水微波消解对锑的检测效果较好,标准土壤9次测定值的相对标准偏差为3.6%,实际样品的回收率为96%-102%.而采用混酸全消解的方式测定值偏低,实际样品的回收率为78%~86%,而且精密度超过5%,这是由于在赶酸过程中样品易被蒸干而造成痕量锑元素的损失. 相似文献
46.
The 1:1 mole ratio reaction of t-Bu3In with Sb(SiMe3)3 results in the formation of the Lewis acid-base adduct t-Bu3In Sb(SiMe3)3 (1), while the dimeric compound [t-Bu2InSb(SiMe3)2]2 (2) is isolated from the 1:1 reaction of t-Bu2InCl with Sb(SiMe3)3. Both the 2:1 reactions of t-Bu2InCl with Sb(SiMe3)3 and t-Bu2InCl with 2 result in the formation of the mixed-bridge compound
(3), however, 1H NMR studies suggest that this compound is unstable in solution. Thermolysis of 1, 2, and t-Bu3Ga Sb(SiMe3)3 (4) results in the formation of nanocrystalline InSb or GaSb through a -hydride elimination pathway. 相似文献
47.
Marina S. Fonari Yurii A. Simonov Victor Ch. Kravtsov Janusz Lipkowski Gabriele Bocelli Edward V. Ganin Vladimir O. Gelmboldt 《Journal of chemical crystallography》1999,29(12):1245-1254
Synthesis and single-crystal X-ray structures are recorded for three adducts of SbF3 with different azacrown ethers. [SbF3·H2O·L1], 1, (L1 = 12,13-benz-1,10-di(azamethyl)-4,7-dioxacyclotetradecane-1,14-dione), triclinic,
, a = 11.234(2), b = 11.691(2), c = 8.869(2) Å, = 94.66(3), = 113.12(3), = 67.82(3)°, Z = 2. [SbF3Cl·H2O·(HL2)], 2, (L2 = monoaza-18-crown-6), orthorhombic, P212121, a = 8.763(2), b = 13.003(3), a = 16.836(3) Å, Z = 4. [(SbF3)2Cl2·(H2L3)], 3, (L3 = 1,10-diaza-18-crown-6), triclinic,
, a = 8.284(2), b = 9.016(2), c = 9.134(2) Å, = 82.92(3), = 65.24(3), = 63.38(3)°, Z = 1. All three structures include SbF3 neutral molecules in the pyramidal mode and the antimony second coordination sphere is completed up to six in different fashions. In 1 the dimeric (SbF3)2 adducts are made up due to the involvement of the symmetry-related fluorine atom in coordination. The distorted octahedron is then completed by water molecule and carbonyl oxygen of L1. The neutral molecules are joined by coordination and hydrogen bonds in the infinite ribbons. 2 and 3 are both comprised of neutral and charged species also bounded via coordination and hydrogen bonds. L2 and L3 in the complexes adopt the form of single and double-charged cations, respectively. The inorganic backbone unites the neutral SbF3 molecules and chloride anions in the alternative mode. The sixth coordination site in the antimony polyhedron is completed by the water molecule in 2 and the ethereal oxygen atom in 3. Alignment of the inorganic entities within the structures of 2 and 3 is strikingly similar. Hydrogen bonding patterns are discussed. 相似文献
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50.
Dr. Xin Wang Dr. Junjie He Dr. Benqing Zhou Dr. Youming Zhang Dr. Jiatao Wu Dr. Rui Hu Prof. Liwei Liu Prof. Jun Song Prof. Junle Qu 《Angewandte Chemie (International ed. in English)》2018,57(28):8668-8673
As a highly stable band gap semiconductor, antimonene is an intriguing two‐dimensional (2D) material in optoelectronics. However, its short layer distance and strong binding energy make it challenging to prepare high‐quality large 2D antimonene; therefore, its predicted tunable band gap has not been experimentally confirmed. Now, an approach to prepare smooth and large 2D antimonene with uniform layers that uses a pregrinding and subsequent sonication‐assisted liquid‐phase exfoliation process has been established. Mortar pregrinding provides a shear force along the layer surfaces, forming large, thin antimony plates, which can then easily be exfoliated into smooth, large antimonene, avoiding long sonication times and antimonene destruction. The resulting antimonene also enabled verification of the tunable band gap from 0.8 eV to 1.44 eV. Hole extraction and current enhancement by about 30 % occurred when the antimonene was used as a hole transport layer in perovskite solar cells. 相似文献