A new chemiluminescence system: MnO(-)(4)-Na(2)CO(3)-KOH and its application in the determination of manganese

A new, fast and simple inorganic chemiluminescence method for the determination of trace amounts of manganese is described. When MnO(-)(4) is injected into 0.40M Na(2)CO(3)-0.70M KOH mixed solution in a reaction cell, the strong chemiluminescence occurs and is recorded. The detection limit is 0.1 ppb Mn and the linear range extends from 0.1 to 10 ppb Mn. A 5-ppb Mn concentration can be determined with a relative standard deviation of 5.6% (15 replicates). The commonly encountered cations do not interfere with the determinations. This method has been successfully applied to the direct determination of manganese in bauxite. The reaction mechanism is also briefly discussed.     

Novel one-dimensional tubelike and two-dimensional polycatenated metal-organic frameworks

Two novel metal-organic frameworks (MOFs) [Zn(TITMB)(OAc)](OH).8.5H(2)O (1) and [Ag(TITMB)N(3)].H(2)O (2) [TITMB = 1,3,5-tris(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene, OAc = acetate anion] were synthesized and their structures were determined by X-ray crystallography. Complex 1 crystallizes in tetragonal space group P(-)4 with a = 23.2664(7) and c = 11.9890(3) A and Z = 8. 1 has a one-dimensional tubelike structure with large inner pore size of approximately 17 A. Complex 2 crystallizes in monoclinic space group C2 with a = 20.7193(10), b = 11.5677(8), and c = 12.2944(6) A, beta = 125.5770(10) degrees, and Z = 4. 2 consists of two-dimensional honeycomb networks that interpenetrate each other to generate a polycatenated structure. In these two complexes, both zinc(II) and silver(I) atoms are four-coordinated with the same tetrahedral coordination geometry. The topologies of 1 and 2 are predominated by the conformations of TITMB, which are cis, trans, trans in 1 and cis, cis, cis in 2, respectively.     

Total synthesis of callipeltoside A

A convergent total synthesis of cytotoxic marine macrolide callipeltoside A is described. The synthesis highlights two stereoselective [4 + 2] annulations for the preparation of associated pyran rings.     

β-D-核糖(RI)与一价、二价金属离子相互作用的理论研究

在HF和MP2水平用全电子(AE)和相对论有效芯势(RECP)方法研究了Ⅰa、Ⅰb、Ⅱa和Ⅱb族金属离子与β-D-核糖(RI)的相互作用.结果表明,RECP能可靠地用于重金属离子;二价金属离子(M2+)比一价金属离子(M+)更易使β-D-核糖(RI)变形;二价金属离子络合物(RI-M2+)比一价金属离子络合物(RI-M+)稳定.电荷布居分析的结果支持上述结论.     

大孔树脂吸附法处理含苯肼工业废水的研究

以Hz-841大孔树脂为吸附剂,95%乙醇为脱附剂处理含苯肼4000~5000mg/L的工业废水,取得了理想的分离效果,苯肼吸附率>99.8%,树脂工作吸附量40~50g/L。     

Microkinetics of H2S Removal by Zinc Oxide in the Presence of Moist Gas Atmosphere

The microkinetics os H2S removeal by ZnO desulfurization in H2O-CO2-N2,H2O-CO-N2 and H2O-O2-N2 gas mixtures was studied by thermogravimetric andlysis.Experiments were carried out with 100-120 mesh ZnO powder at temperatures from 473K to 563K.The results show that the kinetic behaviors of desulfurization could all be described by an improved shrinking-core model.The activation energies of the reaction and the diffusion in different gas atmospheres were estimated.     

交联聚苯乙烯强－弱碱树脂的合成及脱色性能研究

交联聚苯乙烯氯甲基化后，分别与甲胺（或二甲胺）、三甲胺（或α－甲基吡啶、二甲基乙醇胺）混合胺化试剂进行亲核取代反应，合成了一系列同时带有强－弱碱功能基的交联聚苯乙烯树脂，并表征了这些树脂的结构，测定了树脂对甜菊甙的脱色性能，结果表明，这些树脂功能基碱性适中，脱色容量较高，甜菊甙损失较少，再生效率高。     

溶剂萃取法制备Co(PO_3)_2超细微粉

本文用溶剂萃取法成功地制备了偏磷酸钴超细微粉并通过ＸＲＤ，ＩＲ，ＴＧ，ＤＴＡ，ＴＥＭ等实验对超细微粉的组成、结构进行了表征。     

Eu(Ⅲ)、Tb(Ⅲ)、Ho(Ⅲ)、Tm(Ⅲ)和Lu(Ⅲ)与N,N′-二(邻羟基亚甲基)乙二胺配合物的研究

Dutt曾合成稀土离子与N,N′-二(邻羟基亚甲基)乙二胺的稀土双希夫碱配合物。但未见报道Eu(Ⅲ),Tb(Ⅲ),Ho(Ⅲ),Tm(Ⅲ),Lu(Ⅲ)与双希夫碱N,N′-二(邻羟基亚甲基)乙二胺的配合物。本工作合成了这5种双希夫碱配合物。 所用稀土氧化物纯度大于99.9%(上海跃龙化工厂)。水杨醛(CP,用前经减压蒸馏提纯)。稀土硝酸盐Ln(NO_3)_3·xH_2_由稀土氧化物与硝酸反应制得。其余试剂均为分析纯。 仪器为Perkin-Elmer 240-C元素分析仪;Nicolet-5DX型红外光谱仪,KBr压片;岛津UV-