两个以3-硝基邻苯二甲酸为配体构筑的锌和钴配位聚合物的合成、晶体结构和性质

通过水热法合成了2种配位聚合物{[Zn(3-Nbdc)(bpmp)]·H₂O}_n (1)和{[Co(3-Nbdc)(bpmp)(H₂O)]·H₂O}_n (2)(3-Nbdc^2-=3-硝基邻苯二甲酸根, bpmp=1, 4-二(4-吡啶甲基)哌嗪), 并通过X-射线单晶衍射、元素分析和红外光谱对其结构进行了表征。配合物1和2均为二维(4, 4)格子层结构, 其中1含有双核单元, 2含有螺旋金属羧酸链。此外, 对它们的热重、粉末X-射线衍射、固体荧光和磁性性能进行了考察。1显示与游离的3-硝基邻苯二甲酸相似的荧光性质, 锌离子的配位环境和配体之间的耦合作用对其荧光性能几乎没有影响。2在低温区表现出铁磁耦合作用, 高温区的χ_MT值降低主要是由于八面体钴的自旋轨道耦合导致的。     

以硝基对苯二甲酸和4,4'-联吡啶为配体的四个金属Ag配合物的合成、结构多样性和电子光谱

由2-硝基-1, 4-对苯二甲酸和4, 4'-联吡啶作为起始原料合成了4个金属银的配位聚合物, {[Ag(4, 4'-bipy)]·2-Hnbdc·2H₂O ·CH₃OH}_n (1), {[Ag(4, 4'-bipy)(2-Hnbdc)]}_n (2), {[Ag₂(4, 4'-bipy)₂(2-nbdc)]·2H₂O}_n (3), 和{[Ag₂(4, 4'-bipy)₂(2-nbdc)(H₂O)]·2H₂O}_n (4)。通过IR、元素分析、TG、UV和荧光光谱以及粉末衍射等手段, 对配合物进行了表征和性质研究。单晶衍射分析显示, 配合物1为1D阴-阳离子型聚合物, 配合物2为1D双链结构, 且结构中不存在溶剂分子。配合物3和4均为1D链状结构。结构的多样性主要是由配体构象、硝基对苯二甲酸的配位模式以及弱作用(如π-π堆积、Ag…Ag作用以及氢键等)导致的。结构的不同也使得它们的稳定性、紫外吸收以及荧光光谱存在着差异。     

三个含4，4′-(吡啶-3，5-二基)二苯甲酸配体的锌(Ⅱ)、镍(Ⅱ)和钴(Ⅱ)配位聚合物的合成、晶体结构及催化性质

采用水热方法，选用 4，4''-(吡啶-3，5-二基)二苯甲酸配体(H₂pdba)与菲咯啉(phen)、2，2''-联吡啶(bipy)或 2，2''-联咪唑(H₂biim)分别与 ZnCl₂、NiCl₂·6H₂O 和 CoCl₂·6H₂O 在 160 ℃温度下反应，合成了 2 个二维层状配位聚合物{[Zn(μ₃-pdba)(phen)]·H₂O}_n (1)和{[Ni(μ₃-pdba)(bipy)]·3H₂O}_n (2)，以及 1个具有一维链结构的配位聚合物{[Co(μ₃-pdba)(H₂biim)(H₂O)]·H₂O}_n (3)，并对其结构和催化性质进行了研究。研究表明，在70 ℃条件下配合物1在Henry反应中显示出较好的催化活性。优化了反应参数，对反应底物范围也进行了研究。     

以硝基对苯二甲酸和4,4'-联吡啶为配体的四个金属Ag配合物的合成、结构多样性和电子光谱

由2-硝基-1,4-对苯二甲酸和4,4'-联吡啶作为起始原料合成了4个金属银的配位聚合物,{[Ag(4,4'-bipy)]·2-Hnbdc·2H₂O·CH₃OH}_n (1),{[Ag(4,4'-bipy)(2-Hnbdc)]}_n (2),{[Ag₂(4,4'-bipy)₂(2-nbdc)]·2H₂O}_n (3),和{[Ag₂(4,4'-bipy)₂(2-nbdc)(H₂O)]·2H₂O}_n (4)。通过IR、元素分析、TG、UV和荧光光谱以及粉末衍射等手段,对配合物进行了表征和性质研究。单晶衍射分析显示,配合物1为1D阴-阳离子型聚合物,配合物2为1D双链结构,且结构中不存在溶剂分子。配合物3和4均为1D链状结构。结构的多样性主要是由配体构象、硝基对苯二甲酸的配位模式以及弱作用(如π-π堆积、Ag…Ag作用以及氢键等)导致的。结构的不同也使得它们的稳定性、紫外吸收以及荧光光谱存在着差异。     

两个由1H-苯并三氮唑-1-乙酸构筑的镉、银配合物的合成及晶体结构

合成了2个配位聚合物{[Cd(btaa)(phen)(CH₃COO)]·H₂O}_n(1)和{[Ag₂(btaa)(4,4-bpy)₂](NO₃)·2H₂O}_n(2)(Hbtaa=1H-苯并三氮唑-1-乙酸,phen=1,10-邻菲啰啉,4,4-bpy=4,4-联吡啶),采用单晶X-射线、红外光谱、元素分析和热重分析对配合物进行了表征。配合物1中的镉离子通过1H-苯并三氮唑-1-乙酸根桥连成一位螺旋链状结构。在配合物2中,银离子被4,4-联吡啶连接成一维链状结构,这些一维链通过1H-苯并三氮唑-1-乙酸根桥连以及Ag···Ag作用和π-π堆积连接成一维梯子状结构。此外,还研究了配合物1的荧光性质。     

一系列由柔性N,N'-双(3-吡啶甲基)胺构筑的螺旋配合物的合成、结构和性质

合成和表征了5个螺旋配位聚合物{[Cu(Hbpma)(H₂O)₄]₂(SO₄)₃·3.5H₂O}_n (1)、{[Ni(Hbpma)(H₂O)₄]₄(SO₄)₆·10.75H₂O}_n (2)、{[Mn(Hbpma)(H₂O)4](SO₄)_1.5·3H₂O}_n (3)、{[Zn(Hbpma)(H₂O)₄]₄(SO₄)₆·4H₂O·4CH₃OH}_n (4)和{[Cu(Hbpma)2(H₂O)₂](SO₄)2·9H₂O}_n (5),其中bpma代表N,N'-双(3-吡啶甲基)胺。晶体结构分析表明配合物1~4为一维链状结构,配合物5为二维层状结构,其中金属离子由质子化的bpma配体桥连。值得注意的是,采取反-反式构象的柔性bpma配体使得配合物1和2为假螺旋链结构,配合物3和4为螺旋链结构,配合物5为螺旋层结构。同时研究了配合物的磁性和热稳定性。     

4, 4'-二(1-咪唑基)苯硫醚及邻苯二甲酸构筑的两个配位聚合物的合成、晶体结构及荧光性质

在温和的水热条件下,以4,4'-二(1-咪唑基)苯硫醚(BIDPT)和邻苯二甲酸(H₂pht)为配体,合成了2个配位聚合物{[Zn(BIDPT)(pht)]₂·2H₂O·CH₃OH}_n(1)和{[Cd₅(BIDPT)₄(pht)₅]·H₂O}_n(2),分别用X-射线单晶衍射、元素分析和IR等手段对它们进行了表征。结果表明,配位聚合物1和2为2D层状结构,配位聚合物1属于正交晶系,Pbcn空间群;配位聚合物2属于三斜晶系,P2₁/c空间群。此外还考察了1和2的热稳定性和固体荧光性质。     

4,4'-二(1-咪唑基)苯硫醚及邻苯二甲酸根构筑的两个配位聚合物的合成、晶体结构及荧光性质

在温和的水热条件下,以4,4'-二(1-咪唑基)苯硫醚(BIDPT)和邻苯二甲酸(H₂pht)为配体,合成了2个配位聚合物{[Zn(BIDPT)(pht)]₂·2H₂O·CH₃OH}_n(1)和{[Cd₅(BIDPT)₄(pht)₅]·H₂O}_n(2),分别用X-射线单晶衍射、元素分析和IR等手段对它们进行了表征。结果表明,配位聚合物1和2为2D层状结构,配位聚合物1属于正交晶系,Pbcn空间群;配位聚合物2属于三斜晶系,P2₁/c空间群。此外还考察了1和2的热稳定性和固体荧光性质。     

四种同构镧系金属有机框架的合成、结构和荧光传感Fe3+和盐酸环丙沙星

采用溶剂热法,以含氮四羧酸3,5-二(3′,5′-二羧苯)-1H-1,2,4-三唑(H₄BDT)为配体,成功合成了4种同构镧系金属有机框架(Ln-MOFs)：{[La₃(BDT)₂(HCOO)(H₂O)₅]·0.5H₂O·3DMF}_n (1)、{[Ce₃(BDT)₂(HCOO)(H₂O)₅]·3DMF}_n (2)、{[Pr₃(BDT)₂(HCOO)(H₂O)₅]·3DMF}_n (3)和{[Nd₃(BDT)₂(HCOO)(H₂O)₅]·3DMF}_n (4),并采用单晶X射线衍射、粉末X射线衍射、元素分析、热重、红外、N₂吸附实验和荧光光谱对其进行表征。结果表明,这些Ln-MOFs均为单斜C2/m空间群晶体,是双核为无机建筑单元的三维介孔结构。其中2可选择性荧光检测Fe³⁺离子和盐酸环丙沙星药物分子,检测限分别为4.59和0.77 μmol·L^-1。     

四例基于1,4-双(3-/4-吡啶基)-2,3-二氮杂-1,3-丁二烯的配位聚合物的组装和性质:金属离子对结构的影响

通过水热合成法,合成了4例由混合配体构筑的的过渡金属配位聚合物:{[Zn(4-bpdb)(pnba)₂]·4H₂O}_n(1),[Cd(4-bpdb)(pnba)₂]_n(2),{[Cd₂(3-bpdb)₂(OAc)₄]·5H₂O}_n(3),和{[Co(3-bpdb)(pnba)₂(H₂O)₂]·2H₂O}_n(4)(4-bpdb=1,4-双(4-吡啶基)-2,3-二氮杂-1,3-丁二烯,3-bpdb=1,4-双(3-吡啶基)-2,3-二氮杂-1,3-丁二烯,Hpnba=对硝基苯甲酸,HOAc=乙酸),并且分别用X-射线单晶衍射、元素分析、红外光谱、热差分析、X-射线粉末衍射表征了这4个配合物。晶体结构分析表明,配合物1显示出一维锯齿形链状结构,金属锌(Ⅱ)离子具有稍微变形的四面体配位几何构型。而配合物2和3却展现出一维梯状双链结构,镉(Ⅱ)离子展现出五角双锥几何构型。而配合物4却拥有一维直线型链状结构,其中钴(Ⅱ)离子拥有八面体几何形状。上述结果说明,金属离子的几何构型可能对配合物的结构具有重要的影响。此外,还研究了配合物1~3的荧光性质。     

多环芳二酐型聚酯亚胺膜的透气性能

多环芳二酐型聚酯亚胺膜的透气性能李悦生，丁孟贤，徐纪平（浙江大学高分子科学与工程研究所，杭州，３１００２７）（中国科学院长春应用化学研究所）关键词聚醚酰亚胺，聚酯酰亚胺，膜，透气性通常的聚酰亚胺加工性能较差，在芳环二酐的苯环间引入醚键等柔性基团后，其...     

微量元素与疾病诊断治疗的研究现状及展望

对国内外微量元素与疾病的关系及其诊断治疗的研究现状及研究动向进行了综述，包括：微量元素与地方病、癌肿、心血管病、糖尿病、眼病、神经系统病等。参考文献72篇。     

Determination and study on residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil

A QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the determination of benazolin-ethyl and quizalofop-p-ethyl in rape and soil by high-performance liquid chromatography-tandem mass spectrometry has been developed in this study. The residue and dissipation of benazolin-ethyl and quizalofop-p-ethyl in rape and soil were determined with the developed method. The half-lives of benazolin-ethyl in rape straw and soil were 3.7–5.1 days and 14.3–26.3 days, respectively. The half-lives of quizalofop-p-ethyl in rape straw and soil were 5.0-6.1 days and 0.3–9.7 days, respectively. The residue of benazolin-ethyl and quizalofop-p-ethyl in rapeseed and soil were below the detection limit (i.e., 0.5?mg?kg^?1, the maximum residue level of European Union for quizalofop-p-ethyl).     

Synthesis and Optical and Redox Properties of Symmetric and Asymmetric BODIPYs

Herein, we present the synthetic route and the photophysical, electrochemical as well as laser properties of novel red‐emitting boron‐dipyrromethenes (BODIPYs) bearing arylethyne moieties. Such functionality is added along the main axis of the chromophore leading to single‐ and double‐substituted derivatives. The relationship between the dye structure and the lasing properties is studied in detail with the help of the photophysical and electrochemical properties as well as quantum mechanical simulations. The asymmetric substitution of the parent dye induces inhomogeneities in the charge distribution, which leads to an overall loss of the fluorescence capacity, mainly in polar media. Such non‐radiative deactivation processes can be softened by decreasing the electron‐donor ability of the substituent or even avoided by symmetrical substitution. Thus, grafting of the arylethyne moieties at the longitudinal axis of the indacene core results in an effective strategy to develop red‐edge BODIPYs with highly efficient and photostable laser emission.     

Ti-V基储氢合金及其氢化物的物相结构与组分优化设计

Ti-V基储氢合金在室温、常压下即可表现出良好的储氢特性,且质量储氢容量明显高于传统AB₅型储氢合金,从而在氢气的精制和回收、运输和储存及热泵等方面有较早的应用。 此外,在混合气体分离、核反应堆中处理氢的同位素、镍氢电池及燃料电池负极材料等方面也得到了广泛的研究与关注。 基于目前Ti-V基储氢合金的研究现状,概述了该类合金的优势、限制性因素(包括成因)及改性手段。 此外,为了进一步理解Ti-V基合金储氢机理、构建合金组分与储氢特性之间的对应关系,本工作重点围绕Ti-V基储氢合金及其氢化物的结构、组分优化设计展开综述,并对其未来研究方向做出展望。     

钒与糖代谢及糖尿病

微量元素钒作为生物体内必需元素，经证实有很重要的生理学功能，与机体糖代谢有十分密切的关系，且能降低糖尿病动物模型的高血糖，极有可能被开发为治疗糖尿病的药物。     

Conformations and steric and stacking interactions of trisubstituted ureas and thioureas with alkyl and phenyl groups

The monomeric ν(N—H) vibrations of various trisubstituted ureas of the R₂UPh type and -thioureas of the R₂TUPh type have been studied. The trans—out isomerism in the former and the trans—out—cis isomerism in the latter are discussed from the point of view of steric effect. The monomeric ν(N—H) vibrations of RPhUPh and RPhTUPh are also examined. The single band appearing in the spectrum of both ureas is characteristic of the cis form; this suggests the existence of phenyl—phenyl interaction (the stacking interaction proposed by Galabov et al. [10]). Behavior of ν(N—H) vibrations at several concentrations is shown to be clearly different in the three forms (trans, out and cis). The presence of the cis form is confirmed by solvent effect experiments.     

Synthesis of Tyrosol and Hydroxytyrosol Glycofuranosides and Their Biochemical and Biological Activities in Cell-Free and Cellular Assays

Tyrosol (T) and hydroxytyrosol (HOT) and their glycosides are promising candidates for applications in functional food products or in complementary therapy. A series of phenylethanoid glycofuranosides (PEGFs) were synthesized to compare some of their biochemical and biological activities with T and HOT. The optimization of glycosylation promoted by environmentally benign basic zinc carbonate was performed to prepare HOT α-L-arabino-, β-D-apio-, and β-D-ribofuranosides. T and HOT β-D-fructofuranosides, prepared by enzymatic transfructosylation of T and HOT, were also included in the comparative study. The antioxidant capacity and DNA-protective potential of T, HOT, and PEGFs on plasmid DNA were determined using cell-free assays. The DNA-damaging potential of the studied compounds for human hepatoma HepG2 cells and their DNA-protective potential on HepG2 cells against hydrogen peroxide were evaluated using the comet assay. Experiments revealed a spectrum of different activities of the studied compounds. HOT and HOT β-D-fructofuranoside appear to be the best-performing scavengers and protectants of plasmid DNA and HepG2 cells. T and T β-D-fructofuranoside display almost zero or low scavenging/antioxidant activity and protective effects on plasmid DNA or HepG2 cells. The results imply that especially HOT β-D-fructofuranoside and β-D-apiofuranoside could be considered as prospective molecules for the subsequent design of supplements with potential in food and health protection.     

Ferrocene and ferrocenium modified clays and their styrene and EVA composites

In this work, ferrocene- and ferrocenium-containing salts were employed to modify montmorillonite. X-ray measurements show an increase in the interlayer spacing upon clay modification, which means that the larger and more organophilic cations were inserted into the gallery space of montmorillonite. Attempts to prepare nanocomposites of polystyrene and ethylene vinyl acetate copolymers lead to immiscible systems; the morphology of these systems was elucidated with TEM, XRD and cone calorimetry. The thermal stability of the composites is greater than that of the virgin polymer.