Syntheses and structural characterizations of Fe_4S_4 cubane-like cluster compounds containing cycloalkylthiolate ligands

In a reaction system consisting of FeCl2,tetrathiometallate and cycloalkylthiolate,two Fe4S4 cubane-like cluster compounds were obtained with the following crystallographic data:(PhCH2NMe32[Fe4S4 (SC5H9)4](Ⅰ),monoclinic space group P21/c,a=1.6327(4),6=1.1229(3),c=2.802 5( 10) nm,β=94.63(2)°,Z=4,and R=0.074; (Et4N)2[Fe4S4(SC6H11)4](Ⅱ),tetragonal space group I42m,a=1.16705(9),b=1.167 06(2),c=2.063 26(5) nm,Z=2,Dabs=1.28 g/cm3,and R=0.078 The participation of cy-cloalkylthiolate ligand does not obviously arouse the change of the Fe4S4 core structure.Meanwhile,the influence of the cation on the structural symmetry of the Fe4S4 cluster dianion is also discussed.     

Shake-up satellites in Hel photoelectron spectra: N2O4 and CH3O

Low-lying vacant molecular orbitals may lead not only to a breakdown of Koopmans' theorem but also to satellite structure in photoelectron spectra. This paper reports examples of the relatively infrequent appearance of shake-up satellites in Hel photoelectron spectra, namely those of N₂O₄ and CH₃NO. An extended version of the HAM/3 program was used to interpret these spectra.     

聚醚酮酮（PEKK）／4，4′-二苯氧基二苯砜（DPODPS）多嵌段共聚物的合成与性能

采用溶液缩聚法由酰氯端基聚醚酮酮(PEKK)齐聚物和4，4′-二苯氧基二苯砜(DPODPS)制备了PEKK／DPODPS多嵌段共聚物，用DSC、TGA等方法对共聚物进行了表征和性能测试。结果表明，随着共聚物中DPODPS含量的增加，共聚物的熔融温度逐渐降低，而其玻璃化转变温度则逐渐升高。当DPODPS质量分数在32．63％～40．73％范围内时，所得共聚物的Tg为185～193℃，比纯PEKK的Tg高出20～28℃；其Tm为322～346℃，比纯PEKK的Tm降低35～59℃，这既保持了纯PEKK的耐热性，又改善了熔融加工性能。该组成范围内的共聚物的拉伸强度(σi)为86．6～84．2MPa，拉伸模量(M)为3．1～3．4GPa，断裂伸长率(ε)为18．5％～20．3％。     

苯并[b]萘并[2'''',3'''':5,6][1,4]二噻英并[2,3-i]噻蒽-5,7,9,14,16,18-六酮的合成及其三阶非线性光学性能

以1,4-萘醌为原料,合成了含硫的醌构稠杂环化合物苯并[b]萘并[2',3':5,6][1,4]二噻英并[2,3-i]噻蒽-5,7,9,14,16,18-六酮(4),其结构经1H NMR和IR确证.采用波长为800 nm,脉宽为80 fs的Ti:Sapphire飞秒激光,运用双光束简并四波混频法测定了4的三阶非线性光学性能,结果表明,4的三阶非线性光学极化率χ(3),非线性折射率n2,分子二阶超极化率γ和响应时间分别为2.89×10-13 esu, 5.31×10-12 esu, 3.14×10-31 esu和101 fs.并分析了4的分子结构对其三阶非线性光学性能的影响.     

五配位Cu(Ⅰ)配合物[Cu(4′-Phtpy)(PPh_3)_2](BF_4)的合成、结构及光谱性质研究

由[Cu(MeCN)2 (PPh3)2 ](BF4 )和 4′ 苯基 2,2′:6′,2″ 三联吡啶(4′ Phtpy)在室温下反应,合成了一个新颖的具有光致发光性能的五配位配合物[Cu(4′ Phtpy)(PPh3)2 ](BF4 ).对配合物进行了X射线衍射结构表征,并进行了红外光谱、紫外可见光谱、荧光光谱等光谱学分析.晶体属单斜晶系,空间群Pn,晶胞参数:a =1 0 80 7(6)nm,b =1 0 943 (6)nm,c=2 1610(12 )nm,α =90°,β =10 2 785(10 )°,γ =90°,V =2 492(2 )nm3,Z =2,Dc=1 3 5 4g·cm-3.配合物中,Cu(Ⅰ)与 4′ Phtpy的 3个N,2个PPh3的P配位呈变形三角双锥型结构,其轴向由Cu键合联吡啶的末端 2个N所组成,赤道平面由联吡啶的中心N原子和 2个PPh3的P原子所组成     

Quantum chemical study on the one-carbon unit transfer of imidazolinium

One-carbon unit transfer reaction of folate cofactor model compound, 1-acetyl-2-methyl-imidazolinium, with 1,2-diaminobenzene has been studied theoretically with ONIOM method. The result shows that there are two pathways to complete this reaction because the imidazolinium ring has two breaking patterns. Both the two pathways have six steps. They are combination of two reactants, proton migration, break of five-membered ring, formation of benzimidazole derivate, another proton migration, and formation of final products. In each of the above pathways, the two proton migration steps have higher energy, which illuminate that the reaction is catalyzed by general acid-base. This fact agrees with the experimental results of enzymatic one-carbon unit transfer at oxidation level of formate.     

K＋I~2→K^+＋I~2^-离子对生成反应态－态几率与 选态截面的量子散射理论研 究

本文用Miller的-矩阵变分法在Aten-Lanting-Los两态势能面上计算了K＋I~2→K^+＋I~2^-电离反应的态－态几率和选态反应截面,结果表明了低电离阈能、几率的振荡行为及振动增强效应;电离截面随碰撞能及I~2振动量子数的变化规律与实验预测相吻合;讨论了反应机理。     

旋转填充床的流体力学特性与传递过程的理论研究进展

旋转填充床(RPB)是一种高效的强化传递过程设备，亦是一种高效的混合与多相反应设备，在化工、材料、冶金、能源、环保等领域有着广泛的应用前景。本文概要地介绍了近年来对该类装置的流体力学特性和传递过程的理论研究进展。     

κ-卡拉胶热可逆凝胶的非遍历行为研究

采用散射斑纹(speckle)技术,即散射光强涨落法,研究了κ-卡拉胶(KC)热可逆凝胶的非遍历行为.证明了非遍历性的存在,并研究了浓度、温度等条件对该非遍历性的影响.结果表明:该物理凝胶存在非遍历性,并随KC浓度增加,凝胶非遍历性增大;随温度升高,凝胶非遍历性逐渐减小,直至消失.     

还原对Ag/SiO2催化剂高效合成吲哚的影响

以Ag／SiO2作为苯胺和乙二醇一步合成吲哚的催化剂，首次研究了还原对催化剂活性和选择性的影响．结果表明，催化剂前体在150℃以下用氢气含量不超过50%(mol)的氢-氮混合气原位还原其活性和选择性较高．