Synthesis and Structure of Ag_3PSe_4

The title compound Ag3PSe4 was synthesized by the reaction of Ag powder,P2Se5 and Se in a molar ratio of 1:1:1 at 500℃ and structurally characterized by X-ray crystallography.The crystal belongs to orthorhombic,space group Pmn21 with cell parameters:a=7.689(4),b=6.660(3),c=6.379(4)A,V=326.7(3)A^3,Z=2,Dc=6.816g/cm^3,Mr=670.42,F(000)=584,μ=31.302mm^-1,R=0.0606,wR=0.1289 and S=1.012,The 3-D structure can be regarded as constructed from the stacking of puckered Ag-P-Se honeycomb-like sheets along the c direction,in which the Ag,P and Se atoms are bonded to each other to form a chair-like six-membered ring,and the rings then build the sheets by sharing edges.     

Synthesis and Structure of a Manganese(Ⅱ) Complex: [Mn2·(dinitrobenzoic acid)4·(1,10-phen)2]n

The title compound, [Mn2·(dinitrobenzoic acid)4·(1,10-phen)2]n, has a linear chain structure containing binuclear [Mn2·(dinitrobenzoic acid)4(1,10-phen)2] repeat units. It crystallizes in the triclinic system, space group P1- with a = 7.9261(8), b = 12.1329(15), c = 14.847(2)(A), α = 103.845(5), β =101.424(5), γ= 92.618(4)°, Mr= 657.37, V= 1352.3(2) (A)3, Z = 2, Dc= 1.614 g/cm3, F(000) = 666, μ =0.567 mm-1, the final R = 0.0407 and wR = 0.1015 for 4081 observed reflections with I ＞ 2σ(Ⅰ). The Mn atom is six-coordinated by two N and four O atoms, forming a slightly distorted octahedral geometry. All Mn-O and Mn-N bond distances range from 2.093(2) to 2.310(2)(A). Two adjacent octahedral units are bridged together by two pairs of bi-monodentate carboxyl groups of different dinitrobenzoic acids to form an eight-membered ring with chair-typed configuration, thus generating a one-dimensional chain along the a axis.     

Synthesis and magnetic properties of novel polymeric complexes containing bithiazole rings

A novel linear polymer (PFABT) containing bithiazole rings was synthesized by polycondensation of 2,2′‐diamino‐4,4′‐bithiazole (DABT) and formaldehyde. The complexes of PFABT with two transition metal ions (Fe²⁺, Cu²⁺) were prepared for the first time. The polymer was determined through FT‐IR, ¹H‐NMR and elemental analysis (EA), and the complexes were characterized by FT‐IR. The magnetic behaviors of these complexes were measured as a function of magnetic field strength (0–50 kOe) at 4 K and as a function of temperature (4–300 K) under an applied magnetic field of 30 kOe. The results show that PFABT‐Cu²⁺ is a ferromagnet while PFABT‐Fe²⁺ is an anti‐ferromagnet. Copyright © 2007 John Wiley & Sons, Ltd.     

Mg-Nd-Zr-Zn合金的制备及钕对合金组织性能的影响

在RJ-2溶剂和Be的联合保护下制备了Mg-Nd-Zr-Zn系合金. 通过对合金组织的分析, 以及Nd对组织性能影响的研究, 试制出了Nd添加量合理的Mg-Nd-Zr-Zn合金. 经过测试, 认为Nd添加量的增加提高了合金的250 ℃高温抗拉强度, 当Nd添加量超过2.8%时, 合金的高温强化作用不十分显著. Mg-Nd-Zr-Zn合金在250 ℃时的拉伸断裂方式主要是韧性断裂.     

Spectral studies of bridged bisindenylmetallocenes and products of their reactions with polymethylalumoxane in toluene and dichloromethane in the visible region

Quantitative characteristics of changes in the energy of charge transfer from -bonded ligands to metal are presented for the series of structurally similar ansa-metallocene complexes of IVB Group elements. The changes are caused by the solvation effect, replacement of -bonded chlorine ligands by methyl groups and of bridging ethylene groups by dimethylsilylene moieties, introduction of the methyl substituent into position 2 and phenyl substituent into position 4 of the indenyl system, variation of the transition metal in metallocene, and formation of complexes with polymethylalumoxane (MAO) at different Al_MAO/Zr ratios. These effects are found to be additive.     

Coordination Sorption of Urea by Novel Urea Sorbent——Polymer-bound Metal Complexes

Urea can be sorbed by coordination (or complexation)with transitional metalpolyacrylic acid complex and transitional metal-polyacrylamide containing polyethylenepolyamine ligand complexes. The experimental results indicate that the sorbents can sorb about 60mg urea per gram of sorbent at 37℃ and the concentration of urea was 1300.0rag/1 in NaH_2PO_4 and Na_2HPO_4 buffer solution (pH=7.0) and the urea sorption capacity was affected by many factors such as other competive ligands, sorption time, pH and the concentration of urea.     

La-Fe-M(M=Al, Si)化合物磁热性能研究进展

介绍了La-Fe-M(M=AI,Si)化合物在磁热性能研究方面的最新进展。具有NaZn13型晶体结构,含高浓度Fe的La-Fe—M(M=AI,Si)化合物为良好的软磁材料;用少量的Co替代化合物中Si,Al元素可以将化合物的居里温度提高至室温;对La(Fe1-yCoy)xSi13-x化合物,适量的Si,Co组合可使化合物在室温产生可与Gd5Si2Ge2比拟的磁热效应;加入适量的间隙原子H,也可使La(FexSi1-x)13在室温的磁热性能远远大于金属Gd;对含Si量低及含Si量高的La(FexSi1-x)13化合物在相转变点附近由温度和磁场诱导相变的本质做了详细阐述。     

镧对含锡、锑残余元素的34CrNi3Mo钢热塑性的改善作用

采用Gleeble-1500热模拟机测定了不同含量的残余元素锡、锑及稀土镧对低氧、低硫的34CrNi3Mo钢热塑性的影响;采用SEM及EDS手段研究了稀土镧对不同锡、锑含量的钢断裂方式的影响及在其中形成夹杂物的情况。结果表明,用稀土金属可以改善低氧、低硫钢中残余元素对钢性能的危害;镧可以和钢中较低含量的锑作用生成镧锑金属间化合物,并且发现了少量的镧锡金属间化合物。     

含吩噻嗪金属配合物的合成及非线性光学性质研究

本文报道了一种新的配体:10-乙基-3-甲酰吩噻嗪缩肼基二硫代甲酸甲酯(HL)及其金属配合物的合成。采用了元素分析、质谱、核磁共振、红外光谱对配体及其金属配合物进行了表征。此外,并应用紫外、荧光和Z-扫描技术,测定了配体及其金属配合物的荧光最佳发射波长(λ_max^em)、荧光量子产率(Φ_f)、寿命(τ)和非线性光学性质。结果表明它们在DMF溶液中都能发射出较强的橄榄色荧光,配体及其金属配合物都有双光子吸收,并且金属配合物的非线性光学效应比配体明显增强。用半经验量子化学方法(RHF/PM3)计算结果与实验值较为吻合。