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141.
1 INTRODUCTION Great attention has currently been paid to com-pounds formed by the reaction between phosphineand metal alkynyl building blocks[1]. The ligand NP3contains one tertiary nitrogen atom as well as threephosphorous atoms and bonds to the metal ions as atetradentate ligand, affording tetrahedral[2] or triangle-bipyrimidal geometry[3, . In other coordination ca- 4]ses, one[5, , two[7], three P donors[8, 6] … 相似文献
142.
TANG Ding-Xinga② ZHAO Yunb 《结构化学》2005,(3)
1 INTRODUCTION Multinuclear coordination compounds have attrac-ted much attention due to their distinctive optical, elec-tric and magnetic properties as well as enzyme ana-logue[1~4]. It is important for carboxylic acid to de-sign this compound[5~8]. EDTA is a useful titrant formetal determination because EDTA molecule is easyto coordinate with a metal atom (1:1). Other types ofEDTA-M compounds are seldom to know except Ln2-M3(EDTA)3(H2O)11?12H2O[5] and (UO2 )2EDTA[9]. … 相似文献
143.
CHEN Jinga GAO Dong-Zhaoa WANG Shu-Pinga JIANG Zong-Huia b LIAO Dai-Zhenga YAN Shi-Pinga a 《结构化学》2005,24(7):793-799
1 INTRODUCTION The study of spin exchange interaction between metal centers through extended bridges is an active subject in the field of coordination chemistry[1~3]. Polynuclear complexes with extended ligand bri- dges are currently of considerable interest[4~6]. One of the best strategies to design and synthesize poly- nuclear species is ‘complex as ligand’ approach[4, 7]. The oxamide group is proved to be an interesting multiatomic bridge, linking metals in polynuclear complexes[8… 相似文献
144.
1 INTRODUCTION As is widely known, PCDFs together with poly- chlorinated dibenzo-p-dioxins (PCDDs) and poly- chlorinated biphenyls (PCBs) have been included in many blacklists, such as “persistent organic pol- lutants (POPs)” and suspected “environmental en- docrine disruptors (EEDs)”. This is because PC- DFs are chemically and thermally stable and com- plex PCDF mixtures are generally resistant to bio- degradation. Although the concentration of these chemicals is quite low o… 相似文献
145.
StructureofMolybdenumComplexofBenzothiazole-2-thiolate(η~5-C_5H_5)Mo(CO)_2(C_7H_4NS_2)ChengGuo-Bao~a;WuQiang-Jin~b;HuangXiao-Ying~... 相似文献
146.
Hua-jiang Jiang Wei-lin Sun Ren-hua Zheng a Department of Chemistry Materials Taizhou Colledge Taizhou China b Department of Polymer Science Engineering Zhejiang University Hangzhou China 《高分子科学》2006,(1):81-86
A series of polymeric complexes were prepared from Fe~(2 ),Co~(2 ) or Ni~(2 ) and poly(Schiff base)(DAPcIPA), which was obtained by polycondensation of 5,6-diamino-1,10-phenanthroline(DAP)with isophthalaldehyde(IPA).The structures of the polymer and the polymeric complexes were characterized by IR,~1H-NMR and elemental analysis.The magnetic behavior of these complexes was measured as a function of magnetic field strength(0-3.98×10~6 A/m)at 5 K and as a function of temperature(5-300 K)at a magnetic field strength of 2.39×10~6 A/m.Experimental results show that DAPcIPA-Ni~(2 ),DAPcIPA-Co~(2 ) are soft ferromagnets while DAPcIPA-Fe~(2 ) exhibits features of an antiferromagnet. 相似文献
147.
In the ethanol solvent, a nickel(II) complex Ni(C12H10N2O2S)2 upon reaction of 2'-(2-thienylidene)-hydroxybenzoylhydrazide with nickel acetate was synthesized, and its structure was characterized by IR, UV, elemental analysis and X-ray diffraction analysis. The crystal belongs to monoclinic system, space group C2/c with a = 22.052(3), b = 5.9681(6), c = 18.522(2) , β = 110.679(4)°, V = 2280.6(4) 3, Z = 4, Mr = 551.27, μ = 1.606 mm-1, Dc = 1.075 g/cm3, F(000) = 1136 and Rint = 0.0556. The nickel(Ⅱ ) atom in the compound is four-coordinated with two nitrogen atoms from amide and two oxygen atoms from keto group. The biological activities have been measured, show- ing the compound exhibits better anti-bacterial activity than the ligand. 相似文献
148.
Li Zhi-ru TAO Fu-ming PAN Yuh-kang. FENG Ji-kang WU Di. HUANG Xu-rid SUN Ghia-Chung. 《高等学校化学研究》1997,(3)
NewApplicationofbondFunctionBasisSets──abinitioCalculationsofNonlinearOpticalPropertiesofCh_(4-n)F_n(n=1,2,3)LiZhi-ru,TAOFu-mi... 相似文献
149.
1 INTRODUCTION The complexes of amino acid Schiff base have attracted considerable attention because of their bio- activities[1, 2]. Taurine is a special amino acid in be- ings, and recently the complexes of taurine conden- sation salicylaldehyde Schiff … 相似文献
150.
1 INTRODUCTION 5-Fluorouracil (5-FU) is an antimetabolite with good antimicrobial and antitumor activities but has toxic side effects[1~4]. In order to improve the topical delivery of 5-FU and reduce the side effects, many derivatives of 5-FU have been synthesized, some of which are of improved activity. 5-Fluorou- racil-1-acetic acid is a member of the family[5~8], which belongs to the pyrimidine base and is a cyto-toxic analogue of the natural base thymine, and has proven useful in th… 相似文献