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1.
采用水热方法,用联苯三羧酸配体(H_3btc)和菲咯啉(phen)或2,2′-联吡啶(2,2′-bipy)分别与CoCl_2·6H_2O、PbCl_2和ZnCl_2反应,合成了一个单核配合物[Co(Hbtc)(phen)_2(H_2O)]·3H_2O(1)以及2个一维链状配位聚合物[Pb(μ_3-Hbtc)(2,2′-bipy)]_n(2)和{[Zn_3(μ_2-btc)_2(μ_2-H_2O)(2,2′-bipy)_3(H_2O)_5]·8H_2O}_n(3),并对其结构和荧光性质进行了研究。结构分析结果表明3个配合物分别属于正交和三斜晶系,Pna2_1和P1空间群。配合物1具有零维单核结构,而且这些单核钴单元通过O-H…O氢键作用进一步形成了三维超分子框架。而配合物2和3具有基于双核单元的一维链结构。研究表明,配合物2和3在室温下能发出蓝色荧光。  相似文献   

2.
选用2种醚氧桥联三羧酸配体(H_3cpta和H_3dbba)和4,4′-联吡啶(4,4′-bipy)或菲咯啉(phen)与ZnCl_2进行水热合成反应,构筑了2个一维链状配位聚合物[Zn(μ-Hcpta)(4,4′-bipy)(H_2O)]_n(1)和{[Zn_3(μ_3-dbba)_2(phen)_3]·6H_2O}_n(2),并对其结构和荧光性质进行了研究。结构分析结果表明2个配合物分别属于单斜晶系,P2_1和I2空间群。配合物1和2具有两种不同的一维链结构。  相似文献   

3.
采用水热方法,用吡啶-三羧酸配体(H_3L)和2,2′-联咪唑(H_2biim 2,2′-biimidazole)、菲咯啉(phen)、2,2′-联吡啶(2,2′-bipy)分别与ZnCl_2和MnCl_2·4H_2O反应,合成了1个零维配合物[Zn(H_2biim)2(H_2O)_2][Zn(HL)(Hbiim)(H_2O)]_2·8H_2O(1)和2个具有一维链结构的配合物[Mn(μ-HL)(phen)(H_2O)]_n(2)、{[Mn(μ-HL)(2,2′-bipy)(H_2O)]·0.5(2,2′-bipy)}_n(3),并对其结构、荧光和磁性质进行了研究。结构分析结果表明3个配合物分别属于单斜晶系的P21/n和P21/c空间群。配合物1具有3个单核Zn单元组成的零维结构,这些单核单元通过O-H…O/N和N-H…O氢键作用进一步形成了三维超分子框架。配合物2和3具有一维链结构,而且这些链通过O-H…O氢键作用进一步形成了二维超分子网络。研究表明,配合物1在室温下能发出蓝色荧光,聚合物2中相邻Mn髤离子间存在反铁磁相互作用。  相似文献   

4.
采用水热方法,用醚氧桥联四羧酸配体(H_4L)和菲咯啉(phen)、2,2′-联吡啶(2,2′-bipy)与CdCl_2·H_2O反应,合成了2个一维配位聚合物[Cd_2(μ_5-L)(phen)2]n (1)和{[Cd_2(μ_4-L)(2,2′-bipy)_2(H_2O)_2]·2H_2O}n (2),并对其结构和荧光性质进行了研究。结构分析结果表明2个配合物分别属于单斜和三斜晶系,P21/c和P1空间群。聚合物1和2分别具有基于四核Cd_4和Cd_2单元的一维链结构。研究表明,配合物1和2在室温下能发出蓝色荧光。  相似文献   

5.
采用水热方法,用2种联苯三羧酸配体biphenyl-2,5,3′-tricarboxylate acid(H_3bptc)和2-(4-carboxypyridin-3-yl)terephalic acid(H_3cptc)以及菲咯啉(phen)或2,2′-联吡啶(2,2′-bipy)分别与Ni Cl_2·6H_2O和Mn Cl_2·4H_2O反应,合成了一个具有零维四核镍结构的配合物[Ni_2(μ_3-Hbptc)(Hbptc)(phen)_3(H_2O)]_2·4H_2O(1)和一个基于三核锰单元的一维链状配位聚合物{[Mn_3(μ_4-cptc)_2(2,2′-bipy)_2(H_2O)_4]·2H_2O}_n(2),并对其结构和磁性质进行了研究。结构分析结果表明2个配合物均属于三斜晶系,P1空间群。配合物1具有零维四核镍结构,而且这些四核镍单元通过O-H…O氢键作用进一步形成了三维超分子框架。而配合物2中存在一个中心对称的三核锰单元,这些三核锰单元又通过配体进一步连接成了一维链。研究表明,配合物1和2中相邻金属离子间存在反铁磁相互作用。  相似文献   

6.
采用水热法合成了3种新的配合物[Zn(2,2'-oba)(bipy)_2]·2H_2O(1)、[Pb(2,2'-oba)(phen)]_n(2)和{[Pb(2,2'-oba)(bimbp)]·H_2O}_n(3)(2,2'-H_2oba=2,2'-氧基双(苯甲酸),bipy=2,2'-联吡啶,phen=1,10-菲咯啉,bimbp=4,4'-双(咪唑基)联苯),并用X射线单晶衍射、热重分析、红外光谱和元素分析等手段对其进行了表征。配合物1是一个零维结构,通过芳香环π-π堆积作用和强的分子间O-H…O氢键扩展为二维超分子结构。配合物2展现为一维链状结构,通过芳香环π-π堆积作用扩展为二维层状结构。配合物3呈现了一维双链结构,通过强的分子间O-H…O氢键产生了一个二维超分子结构。此外,对配合物1~3的固态荧光性质进行了研究。根据配合物1的晶体结构,利用TDDFT方法对配合物1的光致发光性能进行了理论计算,计算结果与实验数据吻合较好。  相似文献   

7.
采用水热方法,用半刚性三羧酸配体(H_3cpta)和菲咯啉(phen)或2,2′-联吡啶(2,2′-bipy)与CoCl_2·6H_2O反应,合成了一个一维链状配位聚合物[Co(μ_2-Hcpta)(phen)(H_2O)]n(1)和一个二维层状配位聚合物[Co_3(μ_5-cpta)_2(2,2′-bipy)_2]_n(2),并对其结构和磁性质进行了研究。结构分析结果表明2个配合物均属于单斜晶系,P21/c空间群。配合物1具有一维链状结构,而且这些一维链状结构通过C-H…O氢键作用进一步形成了二维超分子网络。而配合物2具有由三核钴单元构筑的二维层状结构。研究表明,配合物1和2中相邻钴离子间存在反铁磁相互作用。  相似文献   

8.
使用3,3′-硫代二丙酸、4,4′-联吡啶和硝酸锰在水热条件下反应合成了1个锰配合物,即{[Mn(DPA)(4,4′-bipy)]·H_2O}_n(1)(DPA=3,3′-硫代二丙酸,4,4′-bipy=4,4′-联吡啶);然后又利用3,3′-硫代二丙酸、1,3-双(4-吡啶基)丙烷和硝酸铜在水热条件下反应合成了1个铜配合物,即{[Cu(DPA)(bpp)(H_2O)]·H_2O}_n(2)(DPA=3,3′-硫代二丙酸,bpp=1,3-双(4-吡啶基)丙烷)。并对它们分别进行了元素分析、红外光谱、热稳定性、X射线粉末衍射和X射线单晶衍射的表征。结果表明:配合物1和2分别由3,3′-硫代二丙酸配体和不同氮杂环分子以及金属离子构筑,形成了二维层状的结构。氢键和π-π作用进一步将二维结构拓展成三维超分子网络。  相似文献   

9.
在水热条件下,合成了2个配位聚合物{[Mn(Hbidc)(2,2′-bpy)(H_2O)_2]·1.5H_2O}n(1)和{[Cd(Hbidc)(phen)][Cd(phen)_2Cl_2]}n(2)(H_3bidc=苯并咪唑-5,6-二羧酸,2,2′-bpy=2,2′-联吡啶,phen=菲咯啉),并通过X射线单晶衍射、红外、元素分析、X射线粉末衍射和热重对配合物结构进行了表征。配合物1是一维无限zig-zag链结构,可以通过O-H…O和N-H…O氢键的相互作用形成三维超分子结构。配合物2也是一维无限链结构。此外,测试了配合物1和2的固体紫外吸收光谱和研究了配合物2的固体荧光性能。  相似文献   

10.
使用2,2′-二硫代二苯甲酸和2,2′-联吡啶(2,2′-bipy)、硝酸铜在水热条件下发生的原位反应合成了一个铜配合物,即[Cu2(C14H8O4S)2(C10H8N2)2](1)(C14H8O4S=2,2′-二羧苯基硫醚,C10H8N2=2,2′-联吡啶);然后又利用2,2′-二硫代二苯甲酸和菲咯啉(phen)、氯化钙在水溶液中合成了一个钙配合物,即{[Ca(C14H8O4S2)(C12H8N2)2]·(H2O)2}n(2)(C14H8O4S=2,2′-二硫代二苯甲酸根,C12H8N2=菲咯啉),并对它们分别进行了元素分析、红外光谱、热稳定性、X射线粉末衍射和X射线单晶衍射的表征。结果表明:配合物1由2,2′-二羧苯基硫醚配体连接形成了一个双核的化合物,通过氢键和氮杂环之间的π…π作用形成三维超分子网络结构。配合物2由二硫代二苯甲酸配体桥联形成了一个一维链状结构,通过氢键和氮杂环之间的π…π作用也形成三维超分子网络结构。并且,对这2个配合物的热稳定性分别进行了研究。  相似文献   

11.
Physico-chemical properties of Chitosan films   总被引:1,自引:0,他引:1  
Chitosan films obtained by dry phase inversion were prepared from an aqueous solution of chitosan in acetic acid. The films, of thickness less than 20 μm, were transparent, very flexible and had smooth surfaces. Increasing the film thickness induced an increase of the internal tensions and the consequent formation of a rough surface. Structural investigations by X-ray diffraction and Fourier transform IR analysis, showed that the chitosan films, as prepared, are amorphous. Further annealing to evaporate acetic acid and water traces, changed the amorphous phase into a more ordered phase, characterized by diffraction peaks at 2θ values of 9, 17, 20 and 23 degrees. Thermal investigations by TG, DTG, and DTA revealed that the decomposition of the chitosan films as prepared proceeds in two stages, starting from 180°C and 540°C.  相似文献   

12.
In the ternary system silver chloride-lithium chloride-sodium chloride the kinetics of the galvanic deposition of silver on graphite electrodes was investigated as well as its dissolution without current in the molten salt saturated with chlorine gas.In addition the emf-values were measured in the temperature range between 923 K and 1,173 K by means of, the formation cell graphite/Ag(s)/AgCl(l)–LiCl(l)–NaCl(l)/Cl2 graphite From these data the partial molar free excessGibbs energies were calculated. Using the equation for a multicomponent system as suggested byRedlich-Kister 1 G AgCl E values were obtained by a non-linear fitting process, where the fit was performed for all investigated temperatures and over the entire concentration range in the ternary system. With the parameters obtained the partial and integral excess valuesG i E ,G E ,H i E ,H E ,S i E andS E were calculated.
  相似文献   

13.
Equimolar mixtures of 3,5-dimethylpyrazole (1) with four NH-imidazoles (2–5) have been studied by13C and 15N CPMAS NMR and by DSC. In three cases, the solid mixture behaves as the sum of the individual components [imidazole (2), 2-methylimidazole (3) and 2,4(5)-dimethylimidazole (5)]. In one case [4,5-dimethylimidazole (4)], the mixture corresponds to a new species in which the dynamic behavior of1 no longer exists.  相似文献   

14.
A plasma induced degradation process has been studied to treat 4-nitrotoluene (4-NT) present as an aqueous pollutant. The plasma was locally generated from a glow discharge around a tip of a platinum anode in an electrolytic solution. The influence of initial pH and Fe2+ on the degradation was examined. Major intermediates resulting from the degradation process were identified. Amongst the aromatic intermediates, p-hydroxybenzoic acid was the predominant degradation product. The formation of oxalic acid, malic acid was also observed. The final products of degradation were NH 4 + , NO 3 and CO2. Based on the analysis of intermediates and the kinetic considerations, the degradation was shown to follow a pseudo-first order reaction hence, a possible reaction pathway was proposed.  相似文献   

15.
An attempt was made to study the oxidation of manganese by air in synthetic waters. A series of batch experments were performed at differnet values of concentration, temperature and pH. Unoxidized manganese in the solution was determined by formaldoxime spectrometric method. Results of these studies indicated that the air oxidation of manganese soluble in water can be effectively performed in basic media and that oxidation yield increasedwith an increase in pH and concentration. The yield was very high in the presence of manganese dioxide, sepiolite or clinoptilolite in solution and, the oxidation was almost completed especially at high values of pH and concentration. The reaction was found to be first order with respect to Mn2+ with a very low activation energy. A yield of 62% was obtained for the air oxidation of wastewater taken from the treatment plant of Corum Municipality.  相似文献   

16.
Thiomorpholine as well as alkyl substituted thiomorpholines and their Sdioxides, respectively, are transformed into the corresponding N-Aminothiomorpholines by nitrosation (1–5) followed by the reduction with zinc in acetic acid/acetic acid anhydride under simultaneous formation of the corresponding N-acetyl derivates, and hydrolysis by hydrochloric acid (6–9). Examples of this method are described. 4-Aminothiomorpholines and their Sdioxides react with aldehydes or ketones to give azomethines (10–31). Acylation with mono-and dicarbonic acid chlorides leads to the N-acyl derivatives32–44.Mannich condensation is also possible. By oxidation with yellow mercury oxide tetracenes are formed (46–47).
Teil der DissertationM. Schmitz, Techn. Hochschule Aachen, 1975.  相似文献   

17.
The formation of the lanthanide (La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Lu) complexes with proline and hydroxyproline has been investigated by potentiometric methods as well as by a turbidimetric one which has provided some additional conclusions. It has been found that 11 and a slight amount of 21 complexes are formed. The deviation from the typical course of the formation function is discussed. It is suggested that the perturbations of complex formation in the systems are caused by hydrolysis. The stability constants of the complexes are reported.
Potentiometrische Untersuchungen an Lanthanid-Komplexen von Prolin und Hydroxyprolin
Zusammenfassung Die Bildung von Lanthanid-Komplexen (La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Lu) mit Prolin und Hydroxyprolin wurde potentiometrisch und mit Hilfe von Trübungsmessungen untersucht. Es wurde festgestellt, daß sich Komplexe der Zusammensetzung 11 und in kleiner Menge auch 21 bilden. Die Abweichung von typischem Verlauf der Bildungskurven wurde untersucht. Es wurde dabei festgestellt, daß für die Störungen in der Komplexbildung die Hydrolyse verantwortlich ist. Die Stabilitätskonstanten wurden bestimmt.
  相似文献   

18.
Substituted azafulvenes were generated by dehydrogenation of 5-methyl-substituted pyrromethenones withDDQ and characterized by UV- and1H-NMR-spectroscopy. Their electrophilic properties were demonstrated using several quenchers and furthermore they were used for a synthesis of verdinoid bile pigments (which easily can be converted to rubinoid systems by the action of NaBH4) with nearly any desired unsymmetrical alkyl substitution patter: The azafulvene spezies was generated by the action ofDDQ on a 5-methylpyrromethenone and was quenched by an 5-unsubstituted pyrromethenone. The resulting rubinoid adduct was dehydrogenated immediatly byDDQ — yields were good to high.
39. Mitt.:Falk, H., Höllbacher, G., Hofer, O., Müller, N., Mh. Chem.112, 391 (1981).  相似文献   

19.
A force field model was designed with respect to the special needs of bile pigments. It is parametrized and tested using partial structures of bile pigments as well as an integral pigment; the solution structures of the molecules were previously deduced using independent experimental methods.
38. Mitt::Falk, H., Schlederer, T., Wolshann, P., Mh. Chem.112, 199 (1981).  相似文献   

20.
Mineralization procedures for blood and urine suitable for the determination of arsenic by Hydride Generation Atomic Absorption Spectrometry (HGAAS) are studied on model samples, and the results are utilized in biological monitoring investigations. The objective of this work is to obtain good total As recoveries for both matrices regardless of added As species (As(III), As(V), DMA, MMA, AsB, or AsC). Prior to the HGAAS analyses, preparation procedures were controlled under optimised conditions by graphite furnace atomic absorption spectrometry (GFAAS). Two preparation procedures for urine give As recoveries close to 100% by HGAAS: a) dry ashing at 420°C with Mg(NO3)2 on a hot plate, and b) microwave oven decomposition with (NH4)2S2O8. For blood samples, As recoveries by HGAAS range between 95 and 108% for all species when using dry ashing after a pretreatment of samples with HNO3 and H2O2 in a microwave oven. Wet digestion with (NH4)2S2O8 in a microwave oven gives recoveries very near 100% for As inorg. and MMA. For other As species in spiked blood samples, recoveries of less than 20% As are found. Precision and detection limits obtained by both techniques are evaluated as well. For arsenic concentrations of 20 μg dm−3 or more in blood and urine, a chemical modifier is recommended for GFAAS analysis; it may or may not be proceeded by a mineralization step. For low As levels encountered in the unexposed population, the HGAAS technique provides reliable results only if a very complete mineralization procedure is used.  相似文献   

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