铁杂环戊二烯配合物的结构稳定性

采用谱学和X射线单晶衍射技术,分别对四苯基铁杂环戊二烯羰基铁配合物(μ₂, η⁴-C₄Ph₄)Fe₂(CO)₆(1)和四苯基取代环戊二烯酮(Ph₄C₄CO)(2)的晶体结构进行了分析和表征。在太阳光和氙灯光(带有4种滤光片)的照射下,利用红外吸收光谱,详细地考察了配合物1的光分解过程和分解产物。实验结果表明,配合物1的光分解速率与光源和波长有关,太阳光的光解速率最快;在同一氙灯光源下,全波长滤光片(320~780 nm)的光解速率最快。本文还对配合物1的热分解和溴分解反应进行了对比研究,结果证实,3种分解反应的主要产物均为配体2。     

膦配体取代的乙基乙撑双铁配合物的合成、晶体结构及电化学催化性能

以母体配合物[Fe₂(CO)₆(μ-SCH₂CH(CH₂CH₃)S)](1)分别与三(2-呋喃基)膦、二苯基丙基膦、双(二苯基膦)乙炔、1,2-双(二苯基膦基)苯和脱羰试剂Me₃NO·2H₂O反应,制备了单取代配合物[Fe₂(CO)₅(L)(μ-SCH₂CH(CH₂CH₃)S)](L=P(2-C₄H₃O)₃,2;Ph₂PCH₂CH₂CH₃,3)、桥联配合物{[Fe₂(CO)₅(μ-SCH₂CH(CH₂CH₃)S)]2(Ph₂PC≡CPPh₂)}(4)和螯合配合物[Fe₂(CO)₄(κ²-(Ph₂P)₂(1,2-C₆H₄))(μ-SCH₂CH(CH₂CH₃)S)](5)。配合物2~5经元素分析、红外光谱、核磁共振氢谱和磷谱表征,并进一步得到单晶X射线衍射的确证。电化学研究表明,在弱酸HOAc作为质子源存在的情况下,这些配合物可以实现催化质子还原产生氢气的功能。     

含异恶唑二铁配合物的合成、表征及电催化产氢性能和抗菌活性

本文报道了 4个含异恶唑基团的二铁配合物的制备及其结构表征。以含羟基二铁配合物[Fe₂(CO)₆(μ-SCH₂CH(CH₂OH)S)] (1)与 5-甲基异恶唑-4-羧酸为原料，经过酯化反应以高产率制备了配合物[Fe₂(CO)₆(μ-SCH₂CHCH₂OOC(5-C₃HNOCH₃)S)] (2)，再分别与三(对甲苯基)膦、三(4-氟苯基)膦或三(2-甲氧基苯基)膦反应，合成了3个含膦配合物[Fe₂(CO)₅(L)(μ-SCH₂CHCH₂OOC(5-C₃HNOCH₃)S)]，其中 L=P(4-C₆H₄CH₃)₃ (3)、P(4-C₆H₄F)₃ (4)、P(2-C₆H₄OCH₃)₃ (5)。使用元素分析、谱学和 X 射线晶体学对新配合物的结构进行了表征。电化学性质研究表明这些配合物可以催化醋酸中的质子还原产生氢气。其中，2拥有最低的过电位而4拥有最高的催化效率。此外，该类配合物还具有一定的抗菌活性。     

水杨醛肟和乙酰氧肟酸钛氧簇合物的合成及光电性质

通过溶剂热合成方法,以水杨醛肟(H₂Saox)和乙酰氧肟酸(H₂Ahox)为染料敏化功能配体,分别以异丁酸(HiBuac)和苯基膦酸(PhPO₃H₂)为辅助配体,与钛酸四异丙酯(Ti (OⁱPr)₄)反应,合成了六核钛氧簇配合物[Ti₆(μ₃-O)₄(Saox)₂(ⁱBuac)₄(OⁱPr)₈](1)和八核钛氧簇配合物[Ti₈(μ₃-O)₂(Ahox)₂(PhPO₃)₄(OⁱPr)₁₆](2)。配合物1和2均通过红外光谱、元素分析和单晶X射线衍射进行了结构表征。光谱性质表明,配合物1和2在可见光区均有吸收,其带隙分别为2.43和2.61 eV。配合物2是首个基于乙酰氧肟酸的钛氧簇,具有光催化析氢性能且速率可达140.2 μmol·g^-1·h^-1。     

3,6-二(N-咪唑/苯并咪唑基)哒嗪配体配合物的合成、结构、荧光及光催化性能

用溶剂热法设计、合成了4个金属-有机配合物[Mn(L¹)₄(OH)₂](1),{[MnL¹(H₂O)₄]SO₄}_n(2),[CdL²(NO₃)₂]_n(3)和{[Co(L²)₂](PF₆)₂}_n(4),(L¹=3,6-二(N-咪唑基)哒嗪,L²=3,6-二(N-苯并咪唑基)哒嗪),并通过元素分析、红外、X射线单晶衍射对配合物结构进行了表征,测试结果表明配合物1具有单核结构,2为一维链结构,配合物3和4均为二维网状结构。此外,对配合物3和4的固态荧光性能及光催化的性能做了进一步研究。     

膦配体取代的乙基乙撑双铁配合物的合成、晶体结构及电化学催化性能

以母体配合物[Fe₂(CO)₆(μ-SCH₂CH (CH₂CH₃) S)](1)分别与三(2-呋喃基)膦、二苯基丙基膦、双(二苯基膦)乙炔、1,2-双(二苯基膦基)苯和脱羰试剂Me₃NO · 2H₂O反应,制备了单取代配合物[Fe₂(CO)₅(L)(μ-SCH₂CH (CH₂CH₃) S](L=P (2-C₄H₃O)₃,2;Ph₂PCH₂CH₂CH₃,3)、桥联配合物{[Fe₂(CO)₅(μ-SCH₂CH (CH₂CH₃) S)]₂(Ph₂PC≡CPPh₂)}(4)和螯合配合物[Fe₂(CO)₄(κ₂-(Ph₂P)₂(1,2-C₆H₄))(μ-SCH₂CH (CH₂CH₃) S)](5)。配合物2~5经元素分析、红外光谱、核磁共振氢谱和磷谱表征,并进一步得到单晶X射线衍射的确证。电化学研究表明,在弱酸HOAc作为质子源存在的情况下,这些配合物可以实现催化质子还原产生氢气的功能。     

含膦配体二铁二硫五羰基配合物的合成、表征及电催化产氢性能

本文报道了4个含膦配体二铁二硫五羰基配合物的合成和结构表征。起始配合物[Fe₂(CO)₆(μ-SCH₂CH (CH₂OOCH) S)](1)与三苯基膦、三环己基膦、三(2-甲氧基苯基)膦或三(4-三氟甲基苯基)膦和脱羰试剂Me₃NO·2H₂O反应,以59%~88%的产率制备了目标产物[Fe₂(CO)₅(L)(μ-SCH₂CH (CH₂OOCH) S)](L=PPh₃(2)、PCy₃(3)、P (2-C₆H₄OCH₃)₃(4)、P (4-C₆H₄CF₃)₃(5))。配合物2~5以元素分析、红外光谱、核磁共振以及单晶X射线衍射进行了表征。电化学性质研究表明配合物1~5均可以实现电化学催化质子还原产生氢气的功能,其中配合物1的催化产氢效率明显优于其它配合物。     

基于两种柔性同分异构羧酸配体的钴(Ⅱ)配合物的合成、结构表征及磁性能研究

分别以E-3-[4-(羧甲氧基)-苯基]丙烯酸(H₂L¹)和E-3-[4-(羧甲氧基)-苯基]丙烯酸(H₂L²)为主配体,合成了3种钴(Ⅱ)配位聚合物：[Co(L¹)(bpp)]_n(1),{[Co(μ₃-OH)₂(L²)₄(bpy)₂(H₂O)₄]·12H₂O}_n(2)和[Co(L₂)(bpy)]_n(3)(bpp：1,3-二吡啶基丙烷,bpy：4,4-联吡啶)。通过元素分析、红外光谱、X射线粉末和单晶衍射对其进行了结构表征。结果表明钴(Ⅱ)离子在这3种配合物中具有不同的配位环境,导致3种配合物具有不同的晶体结构和磁性特征。     

3,6-二(N-咪唑/苯并咪唑基)哒嗪配体配合物的合成、结构、荧光及光催化性能

用溶剂热法设计、合成了4个金属-有机配合物[Mn(L¹)₄(OH)₂] (1),{[MnL¹(H₂O)₄]SO₄}_n (2),[CdL²(NO₃)₂]_n (3)和{[Co(L²)₂](PF₆)₂}_n (4),(L¹=3,6-二(N-咪唑基)哒嗪,L²=3,6-二(N-苯并咪唑基)哒嗪),并通过元素分析、红外、X射线单晶衍射对配合物结构进行了表征,测试结果表明配合物1具有单核结构,2为一维链结构,配合物3和4均为二维网状结构。此外,对配合物3和4的固态荧光性能及光催化的性能做了进一步研究。     

柔性配体构筑的三个构象多样的镧系羧酸配位聚合物:合成,结构和荧光性质

利用2,2''-(1,4-亚苯基)二(亚苯基)二(硫基)苯二羧酸(H₂L¹)和2,2''-(2,3,5,6-四甲基-1,4-亚苯基)二(亚甲基)二(硫基)苯二甲酸(H₂L²)2个柔性二羧酸分别与镧系金属盐反应,通过溶剂热方法合成了3个配位聚合物:{[(NH₂(CH₃)₂][Nd(L¹)₂(DMF)]·2DMF}_n(1)和{[Ln(L²)_1.5(H₂O)(DMF)₂]·2DMF}_n[Ln=Ce(2),Pr(3)]。利用元素分析、红外、粉末X射线衍射、热重分析等对配合物进行了表征。X射线单晶衍射分析表明:3个配合物均为二维的层状结构,并且2个配体在配合物中表现出不同的构象。(L¹)^2-在配合物1中表现出顺式和反式2种构象,(L2²)^2-在配合物2和3中仅表现出反式构象。此外,对配合物的热稳定性和荧光性质也进行了研究。     

Force constant decomposition for penta‐coordinated XH3Cl2‐ (X = C,Si, Ge) structures

Based on the energy decomposition analysis of an interacting system, we propose a method for force constant decomposition analysis with respect to the specific normal coordinate. Using the presented method, we examined the penta‐coordinated system (X = C, Si, Ge), which possesses a three‐center four‐electron bond. The origin of the difference in the stability of the penta‐coordinated D_3h structures was clearly shown to be the effect of electron delocalization–polarization term. © 2018 Wiley Periodicals, Inc.     

“新型高压湿法消解方法”在铅检测中的应用

在食品中和生物材料的微量元素检测中,应用新型高压湿法消解前处理方法,快速、高效地消解各类样品。综合各种因素,对普通食品、生物样品,最佳消解条件为120℃时,3h,样品质量（g）／浓HNO3量（mL）／H2O2（mL）为1：3：1。由回收率试验可知,铅的回收率在95．8％－104．5％,其准确度完全能够满足食品或生物材料中微量金融分析的要求。由于高压湿法消解比干法灰化方法具有快速、高效、准确度高,且消解温度低（低于150℃）,无污染,节省能源等优点,将该法引入食品和生物材料检测工作,可大大提高工作效率,而且可以提高检测准确度。     

Kinetics of thermal decomposition of nickel sulfate hexahydrate

The paper describes the kinetics of all the recorded steps of thermal decomposition of nickel sulfate hexahydrate in air. The thermal decomposition of the salt in air led to NiO at about 1060 K. The kinetic parameters, the activation energyE and the preexponential factorA, and the thermodynamic parameters, the entropy, enthalpy and free energy of activation were evaluated for the dehydration and decomposition reactions. Tentative reaction mechanisms are suggested for each step of the thermal decomposition.     

Crystalline Phase and Decomposition Dynamics of Aluminum Titanate at Different Temperature

The crystalline phase formed during aluminum titanate at 750-1300 ℃ as well as the relationship between its content change and decomposition dynamics was mainly discussed in this paper.Dynamical equation was established for calculating the reaction activation energy.It aimed at providing dynamics basic data for taking up necessary measures to inhibit the decomposition of aluminum titanate.Experimental results showed that aluminum titanate would decompose into TiO2 and corundum at 750-1300 ℃.Content of aluminum titanate would reduce with the increase of decomposition time,and the order of decomposition rates at different temperature was 1100 > 1200 > 1000 > 900 ℃.The decomposition was a chemical reaction with control steps,and could meet the first order reaction dynamic equation-F(G) = [(1-G)-2/3-1] = Kt.According to the calculation,rate constants of different decomposition reaction dynamic equations were K900 = 2.2×10-3,K1000 = 1.2×10-2,K1100 = 4×10-1 and K1200 = 1.5×10-1,and the reaction activation energy ΔGave = 203.21 KJ/mol.     

二苯胺型重氮盐在乙醇中的光、热分解

芳基重氮盐在乙醇中的光热分解已有很多研究［１～７］,但分解产物及提出的分解机理不完全统一．就一般的观点,芳基重氮盐在光热的作用下可以采取异裂或均裂的分解方式,以苯基重氮盐为例,可表示如下：式中Ｘ－为Ｃｌ,ＨＳＯ４,ＢＦ４等负离子异裂产生芳基正离子中间...     

磷矿的超声分解—磷酸的超声萃取研究

磷酸是化学工业上一种重要的无机酸,通过它可以制成一系列重要的产品。例如,用于肥料生产可制得磷酸钙、重过磷酸钙、磷     

The Decomposition of Aqueous Dithionite and its reactions with polythionates SnO2−6 (n = 3–5) studied by ion-pair chromatography

Aqueous dithionite decomposes at 20°C and pH values not far from 7.0 to give thiosulfate and sulfite from which trithionate may form. Addition of thiosulfate accelerates this reaction only at pH < 6. The pH dependence is explained by formation of HS₂O₃^? ions which are reduced by dithionite to HS^? and SO^2?₃. Sulfide destroys dithionite by nucleophilic cleavage, probably with formation of sulfoxylate and thiosulfite ions. The polythionates S_nO^2?₆ (n = 3–5) are reduced by dithionite at pH = 7.0 and 20°C according to S_nO^2?₆ + S₂O^2?₄ + 2 H₂O→S₂O₃^2? + S_n–3SO₃^2? + 4H¹ + 2SO₃^2? The reaction rate rapidly increases with the number n of sulfur atoms. In secondary reactions sulfite attacks S_nO₆^2? ions with thiosulfate formation.     

Thermal decomposition kinetic of reactive solids based on isothermal calorimetry measurements

An isothermal method was applied to measure the thermal decomposition of reactive solids in a sensitive heat flux reaction calorimeter, C80. This technique experimentally clarified the decomposition mechanisms of unstable substances based on the shapes of the heat flow curves, from which autocatalysis, first-order reaction or pseudo-autocatalytic reaction could be recognized. Kinetic parameters were derived from the measured data.     

Synthesis and thermal decomposition of 3,3’-bis-azidomethyl oxetane-3-azidomethyl-3’-methyl oxetane random copolymer

We synthesized a 3,3’-bis-azidomethyl oxetane-3-azidomethyl-3’-methyl oxetane random copolymer [poly(BAMO-r-AMMO)] using the borontrifluoride-dimethyl ether complex/diol initiator system. Hydrogen nuclear magnetic resonance (¹H NMR) was used to analyze the composition of the synthesized copolymer. The results indicated that the composition of the copolymer is in accordance with the molar feed ratio of the monomers. Thermogravimetric analysis (TGA) was used to study the thermal decomposition behavior. The main weight loss step in poly(BAMO-r-AMMO) coincides with the exothermic dissociation of the azido groups in the side chain. In poly(BAMO-r-AMMO), it appears that the other weight loss step is due to the decomposition of the polymer backbone. Kinetic analysis was performed by Vyazovkin’s model-free method. Based on the activation energy data, the random copolymer should form a reticular structure with chemical cross-linking points after the exothermic dissociation of the azido group. Using simultaneous TG-IR-MS data, it was confirmed that this process is controlled by the competitive reactions of intramolecular cyclization and intermolecular cross-linking.