马来酸酐─环氧丙烷共聚物的合成及结构表征

本文将稀土络合物Ｎｄ（Ｐ２０４）３，Ｎｄ（Ｐ５０７），Ｎｄ（ｎａｐｈ）３，Ｎｄ（ａｃａｃ）３．３Ｈ２Ｏ与烷基铝组成的二元体系催化剂用于共聚马来酸酐（ＭＡｎ）与环氧丙烷（ＰＯ）获得成功，并采用１Ｈ－ＮＭＲ研究了共聚的优良催化剂，可得到高转化率，高交替度共聚物，共聚物数均分子量Ｍｎ和分子量分布分别为２０００－３０００，１．３－１．７，共聚物中ＭＡｎ的摩尔含量４０％以上。共聚物组成及序列分布与投料比，催     

钛系Ziegler－Natta催化剂下的丙烯／α－烯烃的共聚合

研究了ＴｉＣｌ＿４／ＭｇＣｌ＿２－三乙基铝（ＴＥＡ）高效载体催化体系下的丙烯／癸烯－１共聚及δ－ＴｉＣｌ＿３－－氯二乙基铝（ＤＥＡＣ）催化体系下的丙烯／辛烯－１共聚合的基本反应规律，考察了铝钛比、温度、共聚单体浓度等对共聚合的影响；对比了两种催化体系的不同，利用非均相Ｚｉｅｇｌｅｒ－Ｎａｔｔａ催化体系下共聚合的非稳态扩散动力学的观点，解释了观察到的共聚合催化效率增加，共聚物粒子增大等实验现象．     

马来酸酐─环氧丙烷共聚物的合成及结构表征

本文将稀土络合物Ｎｄ（Ｐ２０４）３、Ｎｄ（Ｐ５０７）３、Ｎｄ（ｎａＰｈ）３、Ｎｄ（ａｃａｃ）３．３Ｈ２Ｏ与烷基铝组成的二元体系催化剂用于共聚马来酸酐（ＭＡｎ）与环氧丙烷（ＰＯ）获得成功．并采用１Ｈ—ＮＭＲ研究了共聚物三元组序列分布．结果表明，稀土络合催化剂为ＭＡｎ与ＰＯ共聚的优良催化刑，可得到高转化率、高交替度共聚物．共聚物数均分子量Ｍｎ和分子量分布分别为２０００—３０００、１．３—１．７，共聚物中ＭＡｎ的摩尔含量４０％以上．共聚物组成及序列分布与投料比、催化剂种类、溶剂性质等有关．理论计算表明，序列分布符合三级马尔可夫（Ｍａｒｋｏｆｆｉａｎ）过程．     

聚醋酸乙烯酯与铜（Ⅱ）离子的配位反应及其催化作用

以ＥＳＲ、ＵＶ和ＩＲ表征Ｃｕ（２＋）离子与ＰＶＡＣ的配位反应。根据ＣＵＣｌ２·２Ｈ２Ｏ乙醇溶液与ＰＶＡｃ－ＣｕＣｌ２·２Ｈ２Ｏ乙醇溶液的电导率差值随Ｃｕ（２＋）离子摩尔浓度变化的明显转析点得知，１个Ｃｕ（２＋）离子大约能与ＰＶＡｃ４个链节单元配位。证实ＭＭＡ在Ｃｕ（Ⅱ）－ＰＶＡｃ配合物／Ｎａ２ＳＯ３体系的聚合体是无规ＰＭＭＡ，得率为７０％。讨论了ＭＭＡ在Ｃｕ（Ⅱ）－ＰＶＡｃ配合物／Ｎａ２ＳＯ３体系络合催化引发下的游离基反应历程。     

新型高效催化剂乙烯／1—丁烯气相齐聚和共聚制摆弹性体？…

用新型催化体系ＴｉＣｌ４,Ｔｉ（ＯＢｕ）４／ＭｇＣｌ２,ＳｉＯ２和ＺｎＣｌ２／醇／ＡＩＲ３催化乙烯与１－丁烯气均聚及共聚,制得两种共聚物弹性体,发现新型催化剂体系具有独特的齐聚和原位共聚性能,采用＾１３ＣＮＭＲ测定了共聚物链序列分布结构,观察到共聚单体在聚合物链中分布不均匀,存在较长的乙烯链段和较多的１－丁烯嵌段,产物ＤＳＣ谱图表现出复杂的结构熔融行为,存在多种结晶形态,出现熔融肩峰及双峰,怀通常     

稀土配位催化环硫氯丙烷与环氧氯丙烷共聚合研究

研究了稀土配位催化剂对难以开环均聚和共聚的环硫氯丙烷（ＣＭＴ）与环氧氯丙烷（ＥＣＨ）的共聚合。发现稀土乙酰丙酮盐、环烷酸盐等与异丁基铝、水组成的络合催化剂有良好的催化活性，能制备得到类交替共聚物，产率高达６０％以上，分子量频高（［η］＝０．１５ｄＬ／ｇ）。应用ＩＲ、＾１３Ｃ ＮＭＲ、ＧＰＣ、ＶＰＯ等测试手段对共聚物的结构和分子量进行了表征。测定ＣＭＴ（１）与ＥＣＨ（２）共聚合的竞聚率分别为ｒ１＝０     

水溶性铑—膦配合物催化长链烯烃氢甲酰化反应研究—反应条件的影响

本文研究了两相催化体系中，在ＣＴＡＢ（Ｃ１６Ｈ３３ＮＭｅ３Ｂｒ）存在下，水溶性铑－膦配合物ＲｈＣｌ（ＣＯ）（ＴＰＰＴＳ）２对１－己烯氢甲酰化反应的催化性能，详细考察了反应温度、压力、膦／铑比等对催化活性的影响。结果表明，在１．０ＭＰａ恒压下，反应温度１００℃，膦／铑摩尔比为１６，Ｈ２：ＣＯ＝１：１的条件下，１－己烯氢甲酰化的转化频率（ＴＯＦ）可达到３９．８ｍｉｎ＾－１。在此反应条件下，有机相和水相     

新荧光试剂—3—邻甲苯基—5—（2‘—羧基苯偶氮）绕丹宁的荧光性质研究

本文报道新荧光试剂－３－邻甲苯基－５－（２’－羧基苯偶氮）绕丹宁（３ＯＭＲＡＣＰ）的荧光特性，建立了荧光分析测定铜的方法，在ｐＨ５．６时，３ＯＭＲＡＣＰ与铜（Ⅱ）形成螯合物，并在λｅｘ／λｅｍ＝３０８ｎｍ／４０５ｎｍ产生强烈荧光，其荧光强度与铜（Ⅱ）的浓度在０．１～４．０×１０＾－２μｇ／ｇ范围内呈线性关系，检测限达５×１０＾－４μｇ／ｇ。测定了人发中的痕量铜，结果满意。     

浆态床FT合成／固定床ZSM－5改质的合成液体燃料工艺的研究和开发

从合成气制取液体燃料的浆态床ＦＴ合成／固定床２ＳＭ－５改质的反应系统由Ⅰ段鼓泡浆液反应器（内径４０ｍｍ，高４５０Ｏｍｍ）和Ⅱ段固定床ＺＳＭ－５反应器（内径４０ｍｍ，高９００ｍｍ）组成，在温度２５０～２８０℃（Ⅰ段），３００～３４０℃（Ⅱ段），压力１．５～２．５ＭＰａ，空速２．０ＮＬ／ｇＦｅ·ｈ（Ⅰ段），５００～１０００ｈ￣－１（Ⅱ段），Ｈ＿２ＣＯ比０．５～１．５和气速１～２ｃｍ／ｓ范围内，考察了工艺参数对反应性能的影响，１０００ｈ以上的寿命试验的平均结果为：合成气单程转化率６５．１％，产率１００ｇ／Ｎｍ￣３（Ｃｏ＋Ｈ＿２），总烃生产达３５０ｇ／Ｆｅ。使用富ＣＯ合成气时，达１１０ｇ／Ｎｍ￣３（ＣＯ＋Ｈ＿２）。实测的ＦＴ合成反应热为２９３８；５ｋＪ／Ｎｍ￣３（ＣＯ＋Ｈ＿２）。长期运转试验表明，工艺流程合理，设备操作和温度控制可靠。采用的浆液循环回路方法可初步分离蜡中的催化剂。     

两相体系中钌膦配合物催化4—苯基—3—丁烯—2—酮加氢反应的研究

研究了水和有机物组成的两相催化体系中,由ＲｕＣｌ３－ＴＰＰＴＳ（ＴＰＰＴＳ：Ｐ（ｍ－Ｃ６Ｈ４ＳＯ３Ｎａ）３）原位反应生成的催化活性物种对４－苯基－３－丁烯－２－酮（又名苄叉丙酮）的催化加氢反应．考察了钌浓度（１．０×１０－３～６．０×１０－３ｍｏｌ／Ｌ）、氢压（１．０～６．０ＭＰａ）、反应温度（３０～７０℃）、配体浓度（１．２～７．２×１０－２ｍｏｌ／Ｌ）、阳离子表面活性剂（ＣＴＡＢ：十六烷基三甲基溴化铵）及反应时间等对加氢反应活性和选择性的影响,并与以配合物ＲｕＣｌ２（ＴＰＰＴＳ）３为催化剂前体生成的催化活性物种对加氢反应的活性及选择性进行了比较．结果表明,分别由配合物ＲｕＣｌ２（ＴＰＰＴＳ）３及ＲｕＣｌ３－ＴＰＰＴＳ原位反应生成的催化活性物种,都只催化４－苯基－３－丁烯－２－酮的Ｃ＝Ｃ键选择加氢．由配合物ＲｕＣｌ２（ＴＰＰＴＳ）３形成的催化体系的加氢活性及选择性均优于ＲｕＣｌ３－ＴＰＰＴＳ原位反应生成的催化活性物种．阳离子表面活性剂的加入,使加氢反应活性下降,选择性略有提高     

Gels from a semifluorinated n-alkane in fluorinated solvents as a probe for intermolecular interactions

Diblock semifluorinated n-alkanes can form aggregates and gels in fluorinated solvents. We have investigated the thermal behavior of binary mixtures comprising F(CF₂)₈(CH₂)₁₆H and fluorinated solvents. The solvents were perfluorohexane, perfluoroheptane, perfluorooctane, perfluorooctyl bromide, perfluorodecalin, and perfluorotributylamine. The phase diagrams were used to calculate the activity coefficients of the two components and the main excess thermodynamic functions. The solubility and self-assembly behavior of F₈H₁₆ in the fluorinated solvents are related to the different solute–solvent dispersion interactions that depend on the polarizabilities and ionization potentials of the interacting species, and on the structural properties of the solvent.     

Studies on the Formation of Catalytically Active PGM Nanoparticles from Model Solutions as a Basis for the Recycling of Spent Catalysts

The paper presents basic studies on the precipitation of platinum, palladium, rhodium, and ruthenium nanoparticles from model acidic solutions using sodium borohydride, ascorbic acid, and sodium formate as reducing agents and polyvinylpyrrolidone as a stabilizing agent. The size of the obtained PGM particles after precipitation with NaBH₄ solution does not exceed 55 nm. NaBH₄ is an efficient reducer; the precipitation yields for Pt, Pd, Ru, Rh are 75, 90, 65 and 85%, respectively. By precipitation with ascorbic acid, it is possible to efficiently separate Pt, Rh, and Ru from Pd from the two-component mixtures. The obtained Pt, Pd, and Rh precipitates have the catalytic ability of the catalytic reaction of p-nitrophenol to p-aminophenol. The morphological characteristic of the PGM precipitates was analyzed by AFM, SEM-EDS, and TEM.     

PMDA-BPDA-HAB聚苯并噁唑的合成及耐热性

PMDA-BPDA-HAB聚苯并噁唑的合成及耐热性;均苯四甲酸二酐;联苯四羧酸二酐;二羟基联苯胺;聚酰亚胺;聚苯并噁唑;耐热性     

HCOO在Cu(110)、Ag(110)和Au(110)表面的吸附

采用密度泛函理论(DFT)以及广义梯度近似方法(GGA)计算了甲酸根(HCOO)在Cu(110)、Ag(110)和Au(110)表面的吸附. 计算结果表明, 短桥位是最稳定的吸附位置, 计算的几何参数与以前的实验和计算结果吻合. 吸附热顺序为Cu(110)(-116 kJ·mol-1)>Ag(110)(-57 kJ·mol-1)>Au(110)(-27 kJ·mol-1), 与实验上甲酸根的分解温度相一致. 电子态密度分析表明, 吸附热顺序可以用吸附分子与金属d-带之间的Pauli 排斥来关联, 即排斥作用越大, 吸附越弱. 另外还从计算的吸附热数据以及实验上HCOO的分解温度估算了反应CO2+1/2H2→HCOO的活化能, 其大小顺序为Au(110)>Ag(110)>Cu(110).     

Transition metal complexes of the tripodal ligand 4-(2′-pyridylmethyl)-4-azaheptane-1,7-diamine. Crystal structures of [CuLCl]ClO4 and [NiL(MeCN)2](ClO4)2

The tripodal ligand 4-(2′-pyridylmthyl)-4-azaheptane-1,7-diamine has been prepared by reaction of 2-aminemethyl pyridine with acrylonitrile, followed by the reduction of the nitrile groups. Copper(II), nickel(II), zinc(II), cobalt(III) and chromium(III) complexes of the ligand have been prepared and characterized and the crystal structures of the complexes [CuLCl]ClO₄ and [NiL(MeCN)₂](ClO₄)₂ determined. The copper complex is five coordinate with approximate square pyramidal stereochemistry with the apical position occupied by a primary amine donor. The nickel complex is octahedral with the pyridine nitrogen donor lying trans to an acetonitrile ligand.     

SYNTHESIS AND CHARACTERIZATION OF METAL COMPLEXES WITH AMPICILLIN

Abstract

The reaction, in water, of Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) ions with sodium ampicillinate at room temperature has allowed isolation of dimers with the following general formula [M(amp)Cl]₂ × nH₂O (n = 1.5?3.2). The complexes were characterized by elemental analyses, conductivity measurements, magnetic susceptibilities and spectroscopic methods (IR, Raman, EPR and UV-Visible). A dinuclear structure based on octahedrally coordinated metal ions is proposed.     

Magnetism of metal-nitroxide compounds involving bis-chelating imidazole and benzimidazole substituted nitronyl nitroxide free radicals

Coordination compounds based on imidazole and benzimidazole substituted nitronyl nitroxide radicals with transition metal ions and trivalent lanthanide ions are described from the perspective of their magnetic properties.For the transition metal compounds the crystal structures show various metal-nitroxide dimensionalities including mononuclear (0D), one-dimensional (1D) and two-dimensional (2D) complexes. The mononuclear complexes were isolated with most metal ions of the first transition series. One copper(II) complex shows a copper(II)-radical ferromagnetic coupling (J = +75 cm⁻¹) while for the other mononuclear compounds, mainly with manganese(II), the metal-radical interactions are antiferromagnetic. The one-dimensional and two-dimensional complexes are manganese(II) compounds which show canting effects leading to weak ferromagnetism.For the trivalent lanthanide ions [La(III), Gd(III) and Eu(III)], three series of mononuclear complexes were obtained in which the metal center is bound to four, two or one nitroxide radicals depending on the counter ions and ancillary ligands. Unexpectedly, in most gadolinium(III) complexes, the Gd(III)-radical interactions were found to be antiferromagnetic in contradiction with other foundings and previous theoretical models. In support to the magnetic studies, the optical properties of the lantanide complexes have also been investigated and are briefly described.     

New Complexes of Ditopic Ligands with “d” and/or “s” Metal Ions

Abstract

The asymmetric compartmental macrocycles containing one N₂O₂ or N₃O₂ Schiff base and one O₂O₃ or O₂O₄ crown-ether like chamber, have been obtained by condensation reaction of the formyl precursors 3,3′-(3-oxapentane-1, 5-diyldioxy) bis (2-hydroxybenzaldehyde) or 3,3′-(3,6-dioxaoctane-1,8-diyldioxy)-bis(2-hydroxybenzaldehyde) with ethyl ethylenediamine (H₂L_A, H₂L_C), 1,5-diamino-3-azamethylpentane(H₂L_B, H₂L_D), also in the presence of metal ions as templating agents. These ditopic ligands, with dissimilar coordination sites, have been designed and used for the selective complexation of “d” and/or “s” metal ions, respectively into the Schiff base and the crown ether chamber. The selectivity of these processes strongly depends on the size and on the donor atom sets of the sites. The possibility to obtain mononuclear M(L)·nH₂O (M = Ni²⁺, Cu²⁺, Co²⁺), Mn(L)(CH₃COO)·nH₂O or Na(L) and hetero-dinuclear MNa(L)(CH₃COO) (M = Ni²⁺, Cu²⁺, Co²⁺) and MnNa(L)(CH₃COO)₂·nH₂O complexes has been successfully tested. The ligands and complexes have been characterized by ir, nmr, mass spectrometry and magnetic susceptibility measurements.

Two of the ligands used for the preparation of the solid samples, i.e., to H₂L_A and H₂L_B, have been employed to study complexation reactions of Co(II) and Na(I) in solution. In order to obtain information on the ligand preorganization effect toward the complex stabilities, a simpler open chain parent compound of H₂L_B (H₂L_E) has been also prepared and studied. FT-IR spectra show that H₂L_A is unable to complex Na⁺ in DMSO while the complexation reactions of Na⁺ by H₂L_B and of Co²⁺ by H₂L_A take place with slow kinetics. Therefore, thermodynamic data have been obtained only for the systems Co²⁺/H₂L_B and Co²⁺/H₂L_E. The thermodynamic parameters obtained for the complexation reactions show that the pre-organization of the donor atoms in H₂L_B does not add a significant contribution to the stabilities of the complexes. Both H₂L_B and H₂L_E form in DMSO 1:1, 1:2 and 1:3 = M:L complexes with very similar stabilities and almost equal enthalpies of formation. Physico-chemical studies suggest besides that the slow reaction of Na⁺ with H₂L_B is probably due to the formation of a 1:1 complex where the metal cation, initially occupying the O₃ cage of the ligand, slowly binds also the oxygens of the phenolic moieties. Spectral and calorimetric data on solutions containing H₂L_B and different Co²⁺: Na⁺ ratios evidence that in DMSO no stable heterodinuclear complexes form when the neutral ligand is considered.     

具有聚集诱导发光性质的近红外荧光染料

聚集诱导发光(AIE)现象的发现为解决传统有机荧光分子在高浓度和聚集形态下存在的荧光猝灭问题提供了最佳方案,并实现了在光电器件、化学传感、生物成像和靶向治疗等众多领域的广泛应用.随着对AIE 发光机理研究的不断深入,AIE 分子体系得到了极大的扩展.其中,一类具有给体-受体结构的AIE分子能够显著降低分子能隙,使发光分...     

Simple,Selective, and Sensitive Spectrophotometric Method for Determination of Trace Amounts of Nickel（Ⅱ）, Copper （Ⅱ）, Cobalt （Ⅱ）, and Iron （Ⅲ） with a Novel Reagent 2-Pyridine Carboxaldehyde Isonicotinyl Hydrazone

A selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone（2-PYAINH） was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At a pH value of 7.0, 9,0, 9.0, and 8.0, respectively, which greatly increased the selectivity; nickel, copper, cobalt, and iron reacted with 2-PYAINH to form a 1：2 yellow-orange, 1：2 yellow-green, 1：2 yellow and 1：1 yellow complexes, with absorption peaks at 363, 352, 346, and 359 nm, respectively. Under the optimal conditions, Beer＇s law was obeyed over the ranges of 0.01-1.4, 0.01-1.5, 0.01-2.7, and 0.01-5.4 mg/L respectively. The apparent molar absorptivity and Sandell＇s sensitivities were 8.4×10^4, 5.2×10^4, 7.1×10^4, and 3.9×10^4 L·mol^-l·cm^-1, respectively, and 0.00069, 0.0012, 0.00078, and 0.0014 μg·cm2, respectively. The detection limits were found to be 0.001, 0.002, 0.003, and 0.01 mg/L, respectively. The detailed study of various interfering ions to make the method more sensitive was carried out and selective and several real samples were analyzed with satisfactory results.