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Journal of Rare Earths 1997年第3期15卷 57-60页

作者：周执明毛东森叶存孝 College of Chemical Engineering Zhejiang University of Technology Hangzhou 310014 China

A new method is proposed for determining the composition and stability constant of coordination compounds of the form M m R n ; it can be used to differentiate mono and poly nuclear coordination compounds. The equation derived is lg( A i/(A max - A i) m)=n lg c′ R+lg( m·β(c M/A max ) ( m -1) ). The method is based on Bent French limited logarithm method. The demonstration of the proposed method has yielded correct results for Sc 3+ chlorophosphonazo Ⅲ system and Fe 3+ Chromazurol S system.

关键词： Rare earths Mobile equilibrium method Polynuclear coordination compounds Composition stability constant

The Study on the stability constant and Species Distribution of Eu (III) and Tb (III) Complexes with BDBPH

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Chinese Chemical Letters 2005年第12期16卷 1671-1674页

作者： Guo Qiang SHANGGUAN Jun ZHU Ning WANG Jia Zuan NI Department of Chemistry Jining Medical CollegeJining 272013 Key Laboratory of Rare Earth-Chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 Graduate School of Chinese Academy of Sciences Beijing 100039

The stability constants and species distributions of complexes of two lanthanide ions, Eu（Ⅲ） and Tb（Ⅲ）, with a macrocyclic ligand, BDBPH, in 1：1 and 2：lsystem, were determined potentiometrically at 25.0 ℃ and I=0.100 mol L^-l. The two metal ions could form deprotonated mono- or dinuclear complexes with BDBPH after the first two protons of the ligand completely neutralized. At higher pH values, Eu（Ⅲ） could not form hydroxy complexes with BDBPH, while Tb（Ⅲ） could form hydroxy complexes in the type of M2L（OH）, M2L（OH）2, and M2L（OH）3.

关键词： BDBPH Eu(Ⅲ) Tb(Ⅲ) stability constant species distribution

Thermodynamics of stability constant of Binary Complex of Nicotinamide with Mn^(++)

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Chinese Chemical Letters 2003年第11期14卷 1207-1210页

作者： Tuba SISMANOGLU Istanbul University Engineering Faculty Department of Chemistry34850Avcilar-IstanbulTurkey

The stability constants of the binary complexes of Mn2+ with nicotinamide (NA) were determined from potentiometric pH titrations data at 15.0 , 25.0 and 35.0oC and I = 0.1,0.2,0.4 mol L-1 (NaClO4). The formation of binary 1:1 , 1:2 NA-Mn complexes at three different temperatures and the influence of three different ionic strength on their stability were reported. The thermodynamic parameters (DGof, DSof, DHof) for the complex formation reaction were estimated from stability constant at different temperatures.

关键词： Nicotinamide stability constant binary complexes.

Determination of Composition and stability constant of Praseodymium(Pr^(3+))Complex with Tribromoarsenazo(TBA)by Dual-Series Linear Regression Method

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Journal of Rare Earths 1993年第4期11卷 283-287页

作者：魏永巨李克安张占辉童沈阳 Department of Chemistry Peking UniversityBeijing 100871China Department of Chemistry Hebei Teacher's College

A new method,dual-series linear regression method,has been used to study the complexation equilibrium of praseodymium(Pr^(3+))with tribromoarsenazo(TBA)without knowing the accurate concentra- tion of the complexing agent *** 1.2 mol/L HCl solution, Pr^(3+)reacts with TBA and forms 1:3 com- plex,the conditional stability constant(lgβ_3)of the complex determined is 15.47,and its molar absorptivity(ε_3^(630))is 1.48×10~5 L·mol^(-1)·cm^(-1).

关键词： Dual-series linear regression method Praseodymium Tribromoarsenazo stability constant Spectrophotometry

stability constants and Fluorescence of Terbium(Ⅲ) Complexes with Polyaminopolycarboxylates in Aqueous Solution

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Chemical Research in Chinese Universities 1998年第4期14卷 11-16页

作者： GONG Meng lian WU Wei ning SHI Hua hong LEI Heng yi MENG Jian xin YANG Yan sheng Department of Chemistry Zhongshan UnivercityGuangzhou510275

ＩｎｔｒｏｄｕｃｔｉｏｎＡｖａｒｉｅｔｙｏｆｎｅｗｐｏｌｙａｍｉｎｏｐｏｌｙｃａｒｂｏｘｙｌａｔｅｌｉｇａｎｄｓａｎｄｔｈｅｉｒｌａｎｔｈａｎｉｄｅｃｏｍｐｌｅｘｅｓｈａｖｅｂｅｅｎｓｙｎｔｈｅｓｉｚｅｄｉｎｒｅｃｅ... 详细信息

ＩｎｔｒｏｄｕｃｔｉｏｎＡｖａｒｉｅｔｙｏｆｎｅｗｐｏｌｙａｍｉｎｏｐｏｌｙｃａｒｂｏｘｙｌａｔｅｌｉｇａｎｄｓａｎｄｔｈｅｉｒｌａｎｔｈａｎｉｄｅｃｏｍｐｌｅｘｅｓｈａｖｅｂｅｅｎｓｙｎｔｈｅｓｉｚｅｄｉｎｒｅｃｅｎｔｙｅａｒｓｂｅｃａｕｓｅｏｆｔ...

关键词： Terbium(Ⅲ) Polyaminopolycarboxylate Complex stability constant Fluorescence

Voltammetric determination of stability constants of lead complexes with diallyl disulfide, dimethyl disulfide, and diallyl sulfide

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Chinese Chemical Letters 2016年第1期27卷 71-76页

作者： Mohammad Ali Kamyabi Fatemeh Soleymani-Bonoti Saeed Zakavi Department of Chemistry University of Zanjan Department of Chemistry Institute for Advanced Studies in Basic Sciences

The complexation of Pb^（2＋）by diallyl disulfide（DADS）, dimethyl disulfide（DMDS） and diallyl sulfide（DAS）has been studied by differential pulse voltammetry. stability constants,（log b）, of the 1：1（PbL） and 1：2（PbL_2） complexes, where L = ligand, were found to be in the range of ca. 3.8-4.2 and 9.4-10.2,respectively. Complex formation is accompanied with a significant decrease in the peak current and the shift of the Pb2＋/Pb half-wave potential to a higher one upon the addition of the sulfur containing ligands（L）. The formation of 1：1 and 1：2 complexes, i.e., PbL^（2＋）and PbL_2^（2＋）was observed in the case of the three ligands. The consecutive formation constants of labile lead complexes with DADS, DMDS, and DAS were determined at 298 K by the method of De Ford and Hume. Apparently due to the large size of the lead ion,steric hindrance caused by the greater steric bulk of DADS compared to that of DMDS have little or no effects on the formation constants, so that very similar values were obtained in the case of the two ligands. Also, the possible participation of C=C double bonds in coordination with the metal center in the case of DADS appears to compensate for the steric effects caused by the larger size of this ligand. In agreement with the Jorgensen principle of symbiosis, the second formation constants were found to be approximately six orders of magnitude greater than the first ones.

关键词： Garlic oil Organic sulfur compounds Pb^(2+)-DADS,DMDS,and DAS complexes stability constant

The stability constants of Complexes of BDBPH- Metals and Species Distributions

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Chinese Chemical Letters 2001年第10期12卷 925-928页

作者： Guo Qiang SHANGGUAN Jun ZHU Ke Ying WANG Arthur EMARTELL Department of Chemistry Jining Medical CollegeJining 272013 Department of Chemistry Texas A&M UniversityCollege StationTexas 77842

The stability constants of the mononuclear complexes of BDBPH-Zn(II), Cd(II) and Mn (II) were determined by the potentiometric equilibrium measurements, and species distributions were also discussed. The metal ions do not combine with the ligand until the first two protons of the ligand have almost been completely neutralized. The main species were mononuclear complexes with the diprotonated ligand, MH,L. The three metal ions also form mono- and noprotonated (fully deprotonated) complexes, MHL, ML. The relative order of stabilities of the mononuclear complexes, ML, is Zn(II) > Cd(II) > Mn(II). The ligand has strong tendency to form mononuclear complexes with Zn(II), Cd(II) and Mn(II), and it can also form dinuclear complexes at high pH.

关键词： BDBPH stability constant mononuclear complex species distribution

stability constants of Sb^5+with Cl−and thermodynamics of Sb−S−Cl−H2O system involving complex behavior of Sb with Cl

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Transactions of Nonferrous Metals Society of China 2020年第12期30卷 3379-3389页

作者： Gang LI Yun-tao XIN Xiao-dong Lü Qing-hua TIAN Kang YAN Long-gang YE College of Materials Science and Engineering Chongqing UniversityChongqing 400044China School of Metallurgy and Environment Central South UniversityChangsha 410083China School of Metallurgical Engineering Jiangxi University of Science and TechnologyGanzhou 341000China College of Metallurgy and Material Engineering Hunan University of TechnologyZhuzhou 412007China

The stability constants of Sb^5+with Cl−as well as thermodynamics of the Sb−S−Cl−H2O system were *** stability constants of Sb5+with Cl−were obtained by theoretical calculations of the absorbance of a Sb5+-containing solution at different Cl^−concentrations,which was detected by spectrophotometric analysis at certain wavelengths of light(380 nm).The logarithmic values versus 10 of stability constants of Sb^5+with Cl−were 1.795,3.150,4.191,4.955,5.427 and 5.511,respectively,and partly filled the data gaps in the hydrometallurgy of *** presence and distribution of pentavalent antimony compounds under different conditions were analyzed based on equilibrium *** equilibrium calculations were performed for Sb−S−Cl−H2O system,which included the complex behavior of Sb with Cl,and the equilibrium equations of related reactions in this system were integrated into the potential−pH diagram.

关键词： complex behavior stability constant thermodynamics Sb−S−Cl−H2O system

Determination of stability constants of Cadmium-Glycine Complexes by a Unified Treatment for Potentiometric and Polarographic Data

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Chinese Journal of Chemical Physics 2006年第2期19卷 164-168页

作者：张建民石秋芝郑州大学化学系郑州450052

The cadmium（Ⅱ）-glycine system was studied by the two experimental techniques, ion sensitive electrode （ISE） and differential pulse polarography （DPP）, and the experimental data obtained were used by a unified mathematical treatment to calculate the complex stability constants. The combination of the two techniques is of many advantages as ISE can be performed at low [LT]：[MT] ratios and significantly higher [MT], whereas DPP could be used well at large [LT]：[MT] ratios and much smaller [MT]. This makes it possible to study a metal-ligand system in a relatively broader range of experimental conditions that, in turn, provides more information about the metakligand system of interest. Applying the unified mathematical treatment to the cadmium-glycine system, two new complexes MHL and ML2（OH） as well as three complexes ML, ML2 and ML3, reported in literatures, could be modeled and all their stability constants have been refined.

关键词： Metal complex Polarography Potentiometry stability constant

Studies of the Intramolecular Aromatic-ring Stacking Interactions in the Ternary Platinum(Ⅱ) Complexes

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Chemical Research in Chinese Universities 2005年第1期21卷 8-11页

作者： SUNHong-liang ResearchCenterofChemistry＆Analysis ZhejiangGongshangUniversityHangzhou310035P.R.China

The stability constants of some ternary mixed-ligand complexes, Pt(Phen)(CA)+, where Phen=1,10-phenanthroline and CA- =carboxylate, were determined by means of potentiometric pH titration in aqueous solutions(I=0.1 mol/L, KNO 3; 25 ℃), and the stability of them was compared with that of the corresponding binary complexes. It was revealed that the ternary complexes containing phenylalkane carboxylates ligands(PCA-) are much more stable than those formed with formate and acetate. The results indicate that there exist the intramolecular aromatic-ring interactions between the phenanthroline ring of Phen and the phenyl moiety of ligand PCA- in the ternary mixed-ligand Pt(Phen)(PCA)- complexes. The extent of the stacking interactions, which depends on the number of methylene groups between the phenyl moieties and the coordinated phenylalkane carboxylate groups, was calculated. The best-fitted stack was obtained for the complexes with 2-phenylacetate and 3-phenylpropionate as the ligands.

关键词： Platinum(Ⅱ) Mixed-ligand complex Aromatic-ring stacking stability constant