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1.
用分光光度法研究了2.6-二乙酰基吡啶缩二(氨基疏脲)与 Cu2+,Co2+,Ni2+,Zn2+的配位反应,用作图法和自编的LEMIT-S程序计算了配合物的组成,摩尔吸光系数和稳定常数,两法所得的结果基本一致,结果表明,在乙醇中Cu2+与配体daptsc形成Cu2(daptsc)和Cu(daptsc),二者在溶液中共存,而Cu2+在DMF中仅生成1:1配合物,其它金属离子在两种溶剂中均形成1:1型。在两种溶剂中lgβ11的顺序为:Zn > Cu > Ni > Co.  相似文献   

2.
199Sn和23Na核磁共振研究了Na4Sn9-乙二胺体系中加入M(acacen)(M=Cu2+,Ni2+)和Ln(fod)3(Ln=Pr3+,Yb3+,Eu3+)后的化学位移和偶合常数。结果表明,假接触和体积磁化率的变化是引起化学位移变化的主要原因,而Fermi接触的贡献可以忽略。  相似文献   

3.
制备了由2,6—二乙酰吡啶和肼基硫代甲酸酯衍生的希夫碱C5H3N[CH=NNHC(S)XR]2(X=S,R=CH3、C6H5CH2;X=O,R=C6H5CH2).离析出类型为MC5H3N[CH=NN=C(S)XR]2(M=Co2+、Ni2+、Zn2+、Pb2+和Cd2+)的希夫碱配合物.配合物为元素分析、红外、可见—紫外光谱以及磁化率测量所表征.结果指出:上述希夫碱均为N3S2型五齿配体.  相似文献   

4.
本文报道2,2′-(1,2-亚乙基双氮次甲基)二喹啉及其与Cu2+、 Zn2+、 Ni2+、 Mn2+配合物的合成,并通过元素分析、红外光谱、紫外光谱、X-射线粉末衍射、热分析及核磁共振等手段对配体和配合物进行了表征。配合物的化学组成为M.L.(ClO4)2·H2O(M=Cu2+、 Zn2+、 Ni2+、 Mn2+离子;L=C22H18N4)。  相似文献   

5.
本文应用pH-电位法在T=25.0±0.1℃,I=0.5mol·l-1KNO3下测定了Cu2+与甘氨酸(glyH2),β-丙氨酸(β-alaH2),丙二酸(prodH2)和丁二酸(butadH2)等配体形成的配合稳定常数。简要分析了△logK值偏正的原因可能是分子内配体基团之间的相互作用。  相似文献   

6.
合成了以1,8-萘酰亚胺为发色团,以联吡啶为离子受体的Zn2+荧光探针,并进行了表征及离子识别性能的研究。研究表明该化合物对Zn2+具有良好的识别性能,同时相对于Ca2+, Cd2+, Co2+, Cu2+, Hg2+, Fe3+, Mn2+, Ni2+, Pb2+等金属离子具有良好的选择性。  相似文献   

7.
合成了五个2,6-二乙酰吡啶缩肼基硫代甲酸酯双希夫碱合铜(Ⅱ)配合物,用元素分析、磁化率、红外光谱及紫外-可见光谱等对它们进行了表征,研究了配合物的电化学性质和Cu3L22X2(X=Cl-、SCN-)的光电子能谱。结果表明:五个Cu(Ⅱ)配合物均为三核配合物,在Cu3L22(SCN)2中存在Cu(Ⅱ)间的自旋-交换作用。  相似文献   

8.
双核Mo-Fe-S原子簇配合物[Fe(2,2′-bpy)3][S2MoS2FeCl2],是(Et4N)2MoS4、FeCl2和2,2′-联吡啶在乙腈中反应得到的结晶化合物.晶体属单斜晶系,空间群P21/c;a=9.328(3),b=26.788(2),c=13.764(3)Å;β=95.38(3)°;V=3424.2(11)Å3;Z=4;Dc=1.698g/cm3;F(000)=1752.晶体结构用直按法解出;经全矩阵最小二乘法修正,最后R=0.068,Rω=0.071(3933个I>3(σ)(I)的独立衍射).在晶体结构中配位阴离子[S2MoS2FeCl2]2-是排布在阳离子[Fe(2,2′-bpy)3]2+所形成的空腔中.它是以非统计分布的形式存在,从而较准确地测定了各项键参数.Mo…Fe距离为2.773(2)Å,Mo-Sb和Fe-Sb有大致相等的键长.  相似文献   

9.
混合金属配合物MoS4Cu2(NC5H5)4的合成、晶体结构和成键特点   总被引:2,自引:0,他引:2  
混合金属配合物MoS4Cu2(NC5H5)4(NC5H5=吡啶)的晶体属于三斜晶系P1空间群,晶胞参数:a=9.465(50),b=9.463(4),c=14.053(3)Å,α=95.16(3),β=84.89(3),γ=95.91(4)°,Z=2,V=1243(2)Å3;Mr=667.7,Dc=1.784g·cm-3.R因子为0.039,加权Rw因子为0.045.该配合物簇骼具有D2d对称性,Mo-Cu间距分别为2.638Å,2.663Å.端配体吡啶与金属原子Cu间的d*反馈在一定程度上增强了Mo—Cu间的相互作用.  相似文献   

10.
溶液中N-乙酸基取代氮氧杂大环及其配合物稳定性研究   总被引:1,自引:0,他引:1  
用pH电位滴定法在25℃,0.5mol·L-1KNO3水溶液中测定了三种大环化合物:H2L1(1,12-二氮杂-3,4:9,10-二苯并-5,8-二氧杂环十五烷-N,N'-二乙酸);H3L2(1,12,15-三氮杂-3,4:9,10-二苯并-5,8-二氧杂环十七烷-N,N',N″-三乙酸)和H2L3(1,15-二氮杂-3,4:12,13-二苯并-5,8,11-三氧杂环十八烷-N,N′-二乙酸)的逐级质子化常数.又测定了它们与Cu2+、Ni2+、Pb2+配合物的稳定常数,以及H2L3与镧系金属La3+、Pr3+、Nd3+、Eu3+、Sm3+、Gd3+、Dy3+、Yb3+配合物的稳定常数.讨论了三种大环化合物质子化的一般顺序及其与各种离子配位时稳定性选择规律.说明了影响配位稳定性的有关因素.  相似文献   

11.
A series of competitive metal ion transport experiments have been performed. Each involved transport from an aqueous source phase across an organic membrane phase into an aqueous receiving phase. The source phase contained equimolar concentrations of cobalt(II), nickel(II), cupper(II), zinc(II), cadmium(II), silver(I) and lead(II) metal cations. The membrane phase incorporated ionophore, decyl-18-crown-6. The membrane solvents include: chloroform, dichloromethane, 1,2-dichloroethane, nitrobenzene and chloroform–nitrobenzene binary solvents. A good transport efficiency and selectivity of Pb2+ transport from aqueous solutions are observed in this investigation. The selectivity order for competitive bulk liquid membrane transport of the studied transition and post transition metal cations through chloroform is: Pb2+>Co2+>Ni2+>Ag+>Cd2+, but in the case of dichloromethane, 1,2-dichloroethane and nitrobenzene as liquid membranes, the selectivity sequences were found to be: Pb2+>Co2+>Cd2+>Cu2+>Ag+>Ni2+>Zn2+, Pb2+>Co2+>Ag+>Ni2+>Zn2+ and Pb2+>Co2+>Ni2+>Zn2+>Cd2+>Ag+, respectively. The transport rate of the metal cations in chloroform–nitrobenzene binary solvents is sensitive to the solvent composition. The transport processes were studied in absence and presence of the stearic acid and the results show that the sequence of selectivities and ion transport rates change in the presence of stearic acid.  相似文献   

12.
The complexation reaction between 1,13-bis(8-quinolyl)-1,4,7,10,13-pentaoxatridecane ligand (Kryptofix5) and Zn2+, Ni2+, Co2+, Pb2+ and Cu2+ ions were studied conductometrically in acetonitrile solution. The formation constants of the resulting 1:1 complexes were calculated from the computer fitting of the molar conductance and absorbance measurements in various mole ratios. The enthalpy and entropy changes of the complexation reactions were derived from titration conductometry in acetonitrile at various temperatures. At 25 °C, the stability of the resulting complexes varied in the order Pb2+ > Zn2+ > Cu2+> Co2+> Ni2+.  相似文献   

13.
制备了两种表面Schiff碱及其Cu~(2+)、Co~(2+)、Ni~(2+)、Zn~(2+)配合物,考察了它们对H_2O_2分解的催化性能,其活性顺序为:Co~(2+)>Cu~(2+)>Ni~(2+)>Zn~(2+),且与金属离子氧化还原电位有关。溶液的pH值增加有利于催化反应,有机配体的加入则对反应有所抑制。  相似文献   

14.
Three new macrocyclic crown ether ligands containing nitrogen–oxygen donor atoms were designed and synthesized from 1,4-bis(2′-formylphenyl)-1,4-dioxabutane and 4-nitro-o-phenylenediamine. Ion-pair extraction of metal picrates such as Ag+, Hg2+, Cd2+, Zn2+, Cu2+, Ni2+, Mn2+, Co2+, and Pb2+ from aqueous phase to the organic phase was carried out using the novel ligands. The solvent effect over the metal picrate extractions was investigated at 25 ± 0.1 °C by using UV–visible spectrometry. The extractability and the values of the extraction constants (log Kex) were determined for the extracted complexes.  相似文献   

15.
用气相法和液相法分别在Y型分子筛的超笼中合成了Co2+、Ni2+的乙二胺配合物,并用红外(FT-IR)、顺磁共振(ESR)等方法对配合物的组成和稳定性进行了研究。CO2+的单核配合物在室温下可与O2分子形成加合物,这种优先并可逆地吸附氧气的性能在氧气富集、对空气进行氧氮分离和食品保鲜等方面有广泛的用途。  相似文献   

16.
《Analytical letters》2012,45(17):3074-3087
Abstract

Insoluble porous solid, macrocyclic 22-membered ring, 1-oxa-6,9,12,15,18-pentaaza-2,22-disilacyclododocosane polysiloxane ligand system has been prepared by the reaction of a macro-silane agent with tetraethylorthosilicate. The macro-silane agent was prepared by the reaction of imino-bis(N-2-aminoethylacetamide) ligand with 3-iodopropyltrimethoxysilane in 1:3 molar ratio. The new prepared polysiloxane system exhibits variable potentials for the extraction of metal ions (Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Ag+, Cd2+, Hg2+, and Pb2+) from aqueous solutions. The ligand system shows high capacity to extract silver, lead, and mercury. Chemisorption of the metal ions by the ligand system at the optimum conditions was found in the order Ag + > Pb2+ > Hg2+ > Cu2+ > Ni2+ > Fe3+ > Co2+ > Cd2+ > Zn2+.  相似文献   

17.
The selective liquid–liquid extraction of various transition metal cations from the aqueous phase to the organic phase was carried out using a 14-membered N2O2S2-macrobicycle. Metal picrates such as Pb2+, Co2+, Zn2+, Ni2+,Cu2+ and Cd2+ were used in this extraction studies. It was found that the ligand showed moderate selectivity towards Pb2+ only among the other metals. The extraction constant (log K ex) was determined to be 13.8 for Pb2+ complex.  相似文献   

18.
The extraction of ammine complexes of Cu2+, Cd2+, Ni2+, Co2+ and Zn2+ by synthesised manganese, nickel and zinc silicates has been studied at different pH and ionic concentrations in the external solution. It has been found that the uptake of the metal ion Co2+, Cu2+ and Zn2+ increases with increase in pH of the external solution, attains a maximum and then decreases. However, the uptake for Cd2+ and Ni2+ increases continuously. The qA values of all the silicates increases with the increase in the concentration of the exchanging ion and its order for the investigated metal ions is Ni2+ < Co2+ < Cd2+ < Zn2+ < Cu2+.  相似文献   

19.
The formation and dissociation kinetics of the pentaco-ordinated Cu2+, Ni2+, Co2+ and Zn2+ complexes with 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane (4-MeCyclam-14) was studied by pH-stat techniques and spectrophotometrically. The rates of the reactions between 4-MeCyclam-14 and each of the four metal ions, although slower than normal complexations by a factor of 103?104, closely follow the order Cu2+ > Zn2+ > Co2+ > Ni2+, found for the rate of water exchange. This implies that beside water exchange an other constant factor plays an important role in the rate determing step. The dissociation of the pentaco-ordinated 4-MeCyclam-14 complexes is acid catalyzed. The limiting rate for acid dissociation is not reached even in 2.5M HNO3 in the case of Ni(4-MeCyclam-14)2+. From the formation and dissociation rates stability constants have been calculated, which do not show any macrocyclic effect.  相似文献   

20.
The kinetics of the exchange between MnO or Mn3O4 and Co2+, Cu2+, Ni2+, or Zn2+ ions in solution, was determined by measuring the γ-activity of56Mn acquired by the solution after shaking with the neutron irradiated solid. The results indicated a fast exchange followed by a slower apparently diffusion-controlled exchange. The exchange capacity increased in the series: Co2+<Ni2+<Cu2+=Zn2+ for MnO and Ni2+<Co2+<Zn2+<Cu2+ for Mn3O4. The trends could not be satisfactorily explained by the ionic radii or crystal field stabilisation-energies. In the case of MnO, the results were discussed in terms of the estimated standard enthalpy change of the exchange reaction.  相似文献   

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