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1.
以阳离子交换微柱分离与ICP-AES检测联用技术为分离/检测手段,系统地研究了不同配体配合物体系中铝的形态及其分布.当pH=6.0时,溶液中非稳定态单核铝被微柱所保留,而稳定态配合铝直接从微柱中流出.所选择的研究体系分别为:Al-氟化物(Al-Fluoride),Al-磷酸盐(Al-Phosphate),Al-柠檬酸盐(Al-Citrate),Al-草酸盐(Al-Oxalate)及Al-EDTA.在确定的pH值条件下,研究了不同的摩尔比[n(Al)/n(配合剂)]对铝的形态分布的影响,得到了一些对实际应用有指导意义的规律性结论.  相似文献   

2.
本文合成了2种第三主族金属铝和镓咔咯配合物Al(tpfc)、Ga(tpfc)、Al(tpfc)(Py)2、Ga(tpfc)(Py)。测定了在甲苯溶液中,铝和镓咔咯的电子光谱、荧光光谱、荧光量子产率及荧光寿命。在不同溶剂作用下,铝和镓咔咯的电子吸收光谱和荧光光谱的峰位置和强度存在差异。在二氯甲烷溶液中,轴向配体吡啶能促进铝和镓咔咯的π-π堆积。不同轴向配体与金属咔咯的结合能力为:咪唑>4-甲基咪唑>吡啶,铝比镓的咔咯配合物有更强的结合轴向配体的能力。  相似文献   

3.
近二十年来,高分辨率 27Al核磁共振( 27Al NMR)广泛应用于研究 Al?离子水解过程 ,Al?与环境生物配体的配位化学 ,环境与生物样品中铝含量测定和形态分析 ,监测铝在植物、动物、酵母菌等微生物中的转运过程 ,具有快速、直接、非破坏性等优点。 27Al NMR不仅适用于高浓度的溶液,也可应用于低浓度 (10- 6mol· L- 1)的实际环境、生物样品。应用 27Al MAS NMR可直接对固态样品中铝的存在状态和含量进行表征和测量。本文中对 27Al NMR的应用进展作一评述,并总结了近二十年来文献发表的 27Al化学位移数据。引用文献 70余篇。  相似文献   

4.
苯甲酰水杨酸铽与PVK混合体系的发光特性   总被引:5,自引:6,他引:5  
合成了一类以苯甲酰水杨酸(benzoyl salicylic acid,BSA)为第一配体,邻菲罗啉(1,10-phenanthroline,Phen)为第二配体的稀土铽配合物,将导电高分子材料PVK引入到配合物中,制成了结构为ITO/PVK:Tb(BSA)3phen/PBD/Alq/LiF/Al电致发光器件,并对该配合物的吸收特性及电致发光和光致发光性能进行了研究,实验数据表明在PVK与Tb(BSA)3phen之间存在着Forster能量传递,该配合物具有很好的光致发光和电致发光性能。本文同时比较了几种不同PVK掺杂浓度对于器件性能的影响。  相似文献   

5.
Eu(BSA)3phen与PVK共混体系的光致和电致发光特性的研究   总被引:5,自引:4,他引:5  
合成了一类新型的以苯甲酰水杨酸(benzoyl salicylic acid,BSA)为第一配体,邻菲罗啉(1,10-phenanthroline,phen)为第二配体的稀土配合物Eu(BSA)3phen,将导电高分子材料PVK引入到配合物中,制成了结构为ITO/PVK:RE配合物/LiF/Al的电致发光器件.通过测量电致发光和光致发光光谱,发现PVK:RE配合物混合体系存在着能量传递,并对Eu(BSA)3phen与PVK共混体系的光致发光和电致发光机制进行了分析.同时比较了几种不同PVK掺杂浓度对于器件性能的影响.  相似文献   

6.
近二十年来,高分辨率27Al核磁共振(27Al NMR)广泛应用于研究Al(Ⅲ)离子水解过程,Al(Ⅲ)与环境生物配体的配位化学,环境与生物样品中铝含量测定和形态分析,监测铝在植物、动物、酵母菌等微生物中的转运过程,具有快速、直接、非破坏性等优点。27Al NMR不仅适用于高浓度的溶液,也可应用于低浓度(10-6mol·L-1)的实际环境、生物样品。应用27Al MASNMR可直接对固态样品中铝的存在状态和含量进行表征和测量。本文中对27Al NMR的应用进展作一评述,并总结了近二十年来文献发表的27Al化学位移数据。引用文献70余篇。  相似文献   

7.
对氯化钕丙酰胺配合物与烷基铝组成的二元体系催化 4 乙烯吡啶极性单体聚合反应进行了研究 ,考察影响聚合反应的各种因素。氯化钕配合物催化活性随Al Nd(摩尔比 )、催化剂浓度、聚合时间的增加而增大 ,添加吡啶给电子体可提高氯化钕配合物催化活性。不同种类烷基铝对催化活性的影响活性顺序为 :(i Bu) 3Al>(i Bu) 2 AlH >Et3Al。聚合温度在 50℃时 ,配合物催化活性最高。  相似文献   

8.
结合国内外各课题组研究,从27Al NMR实验参数和铝形态研究两方面综合评述了液体27Al NMR的发展研究现况。首次明确提出27Al NMR测定中设置合适的预采集延迟时间的作用。将为进一步开展的27Al NMR测定研究提供有价值的参考。  相似文献   

9.
以8-羟基喹啉为原料,合成了5-(烯丙氧)甲基-8-羟基喹啉配体及其铝配合物,并通过红外光谱对配体和配合物进行了表征,通过荧光光谱研究了配合物的光致发光性能。  相似文献   

10.
采用27Al NMR法、渗析法与原子吸收分光光度法,研究了柠檬酸铝(AlCit)溶液中铝的形态及pH值的影响.结果表明,在AlCit溶液中存在两种形态的Al,一种是分子态AlCit,另一种是胶态Al, pH值增加时,分子态AlCit的量减少而胶态Al的量增加.  相似文献   

11.
We describe the synthesis of a number of 1,3-azol-2-yl-, 1,3-benzazol-2-yl-, and azinyl-based bis(o-azaheteroaryl)methanes (LH, L(-) = Het(2)CH(-)) and their coordinating properties toward divalent transition metals (Zn, Cu, Co, Ni, Hg, Pd). This extended investigation includes both symmetrical and unsymmetrical ligands based on several substituted and/or unsubstituted thiazole, benzothiazole, benzoxazole, benzimidazole, pyridine, and quinoline derivatives. Depending on the structure and electron properties of the ligand, a vast set of neutral chelates ML(2) were obtained, where the ligand is present in its carbanionic form L(-). Additionally, we have prepared salt complexes [M(LH)(n)]X(m), where the ligand is present as a neutral system. Neutral chelates were typically obtained by the reaction of the ligand with metal acetates in alcoholic solution; salt complexes were formed by reaction with other metal salts such as chlorides. By exploring the coordinating properties of several bisheteroarylmethane ligands based on heteroaromatics of variable pi-electron structure and substitution pattern, we demonstrate that the formation of neutral chelates is strictly dependent on the electron-withdrawing capacity (charge demand) of the heteroaromatic moiety. The latter primarily dictates the efficiency by which the negative charge of the anionic ligand L(-) is stabilized by delocalization in ML(2) and, therefore, the stability of the chelate itself. On the basis of the large number and the variable nature of the nitrogen ligands used, we confirm the general validity of the charge-demand-dependent formation of chelates. This key factor can therefore be used for the efficient design of new pi-deficient heteroaromatic nitrogen ligands in chelates of great potential in many synthetic, catalytic, and technological fields.  相似文献   

12.
二茂铁甲酰羟胺衍生物分子中含有N-羟基和α-羰基,可与过渡金属形成螯合物.我们试图将该类螯合物用作复合固体推进剂的燃速调节剂,为此,研究了该类化合物的合成方法及其性质,并使它们与铜(Ⅱ)螯合制成铜螯合物.  相似文献   

13.
Bis(hetarylhydrazones) synthesized for the first time were used as ligands to obtain a number of binuclear copper(II) chelates from copper acetate and chloride. The physicochemical and, first of all, magnetic properties of the resulting complexes were studied. Analysis of the calculated exchange parameters showed that they differ significantly from those obtained previously for analogous binuclear metal chelates containing the identical set of donor atoms. Possible reasons for the differences in the magnetochemical behavior of the binuclear complexes obtained are discussed.Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 2, 2005, pp. 157–160.Original Russian Text Copyright © 2005 by Lukov, Gevorkyan, Dontsova, Kogan, Popov, Dykov.  相似文献   

14.
Chelates of 8-Quinolinol Derivatives. VI. Complex Formation and Extraction of Copper with Alkyl and Alkenyl Substituted 8-Quinolinols The copper chelates of a series of 7-substituted alkyl and alkenyl 8-quinolinols as well as 2-, 5-, and 7-methyl-8-quinolinols were synthesized and the chemical bonding was studied by EPR spectroscopy in chloroform and pyridine solution. Spectral changes in the chloroformic solutions of the chelates produced by pyridine are the result of a slow destruction reaction. For the extraction of copper in the chloroform/water system the extraction parameters as well as distribution data of the ligands were determined.  相似文献   

15.
The data on competitive binding of ligands in metal complexes with ambidentate ligands (Schiff bases and -aminovinylketones) were summarized. Special attention is given to chemical and electrochemical syntheses and structural study of novel chelates of heterocyclic enaminoketones with antipyrine substituent that form tetrahedral (Cu2+, Zn2+) or octahedral (Co2+, Ni2+) structures.  相似文献   

16.
New azo sulfadrugs of 2-mercapto-S-azo ( p '-heterocyclo-substituted benzene-sulfonyl) benzothiazole derivatives (L 1 and L 2 ) were synthesized by coupling of p '-heterocyclo-substituted-benzene-sulphonyl diazonium salts with 2-mercapto-benzothiazole in acid medium. The corresponding iron(III), cobalt(II), nickel(II), copper(II), and mercury(II) chelates were prepared in a 1:1 metal to ligand molar ratio. The ligands and their chelates were characterized on the basis of microanalysis, UV, IR, and H 1 -NMR spectrometry. Thermal decomposition of the complexes was studied in static air. On the basis of the thermogravimetric curves some decomposition steps could be correlated with the proper decomposition products. The photochemical behavior of the ligands and their complexes were investigated. The photosensitivity shown by the complexes was attributed to the photoreactivity of their free ligands. The ligands and their chelates were screened in vitro for their antimicrobial activities (antibacterial and antifungal). The complexes induce a remarkable increase in the antimicrobial activity compared to the corresponding ligands.  相似文献   

17.
The thermal stabilities of 2-mercapto-3-formylbenzo[b]thiophene and its chelates with Cu(II) and Co(II), of 2-mercapto-3-iminomethylbenzo[b]thiophene and its chelates with Cu(II), Co(II), Ni(II), and Zn(II), and of N,N′-bis(2-mercaptobenzo [b]-3-thenylidene)ethylenediamine and its chelates with Cu(II), Co(II), and Ni(II) were investigated by differential-thermal and thermogravimetric analysis. The temperature of the onset of decomposition and the character of the decomposirion of the ligands and chelates were established. It was found that the investigated chelates can be arranged in the following order with respect to increasing thermal stability: Cu < Co < Zn < Ni. The most thermally stable ligand is N,N-bis (2-mercaptobenzo[b]-3-thenylidene)ethylenediamine. The effectiveness of the ligands and chelates as stabilizers for polycaproamide fibers were compared. It was found that of the investigated compounds, the copper chelates are effective stabilizers. In a study of the thermal behavior of the copper chelates in an inert gas atmosphere it was established that the character of the thermal decomposition of the most effective of them — {it(N,N′-bis)2-mercaptobenzo[b]-3-thenylidene)-ethylenediaminato} Cu(II) — is identical both in the presence of air oxygen and in a nitrogen atmosphere, i.e., the chelate does not undergo oxidation at temperatures up to 270?C.  相似文献   

18.
The reactivity of α-phenyl-β-mercaptocinnamaldehyde and α-(2-pyridyl)-β-mercaptocinnamaldehyde towards thiophilic metals was studied and some complexes of nickel, cobalt, copper, palladium, zinc, lead and mercury with these ligands were prepared. The chemical bonding in the complexes was examined by IR spectroscopy. The reaction of the Bis(α-phenyl-β-mercaptocinnamaldehydato)-nickel with amines gave the corresponding aldimine chelates, by the action of hydrogen sulfide the nickel chelate of α-phenyl-β-mercaptocinnamthioaldehyde was formed.  相似文献   

19.
Two different types of modified imido and phosphaneiminato ligands are investigated, namely chelate ligands and redox‐functionalised ligands. The first examples of di(organoimido)chromium as well as di(phosphaneiminato)titanium and niobium chelates are described. Furthermore, the first complexes containing redox‐functionalised organoimido ligands are presented, together with the first structurally characterised redox‐functionalised phosphaneiminato complex. Compounds of the type [(RN)2M(CH2Ph)2] (M = Cr, Mo) are used as catalysts for the (co‐)polymerisation of the polar olefins methyl methacrylate, acrylonitrile and vinyl acetate. A range of X‐ray crystal structure determinations provide clear evidence for the quantum‐chemical result that, similar to organoimido complexes, the potential energy well for the angle at the nitrogen atom is very shallow for phosphaneiminato complexes.  相似文献   

20.
Syntheses of Bis-enaminoketones are described, which are able to form square planar chelates with transition metals. Tetra- and multidentate ligands were prepared from anilinomethylene derivatives of 1,3-dicarbonyl compounds and various diamines. Lipophilic ligands were prepared with respect to potential use as carriers in liquid membrane permeation. Incorporation of the ligands into a polymer (via a spacer group) was performed by radical polymerization.
  相似文献   

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