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1.
<正> The title com pound (HHOMP) has been synthesized with the pho-toinduced condensation of acetone and pyrrole in the presence of iodoaromatic hydrocarbons, and its molecular and crystal structures have been determined by X-ray analysis. C28H36N4, Mr = 428. 63, triclinic; space group P1; a =10. 165(3), b = 10. 185(2), c=13. 012(3)(?); α=85. 41(2), β=67. 84(2), γ= 89. 75(2)°; V = 1243 (?)3; Z = 2; D = 1. 145g. cm-3; μ= 0. 635cm-1; F (000) = 464. Although the HHOMP molecule twists, it is found that the four nitrogen atoms are still in a plane.  相似文献   

2.
用从头算方法,在HF/STO-3G、HF/3-21G和HF/6-31G水平上研究了小硅化物SiX^m4的成键倾向性。计算结果表明,所研究的分子势能曲线均有稳定的极小值(SiLi4除外)。与已知的稳定分子SiH1、SiF4和SiCl4比较,含惰性元素的未知分子SiHe^4+4、SiNe^4+4和SiAr^4+4比含碱金属和碱土金属的未知分子SiLI4、SiNa4、SiBe^4+4和SiMg^4+4有  相似文献   

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张宏  孙仁安  李纳  阎杰 《结构化学》2006,25(3):279-284
1 INTRODUCTION In the later 60s of last century, silicon substituted for germanium to present as mainstream in semicon- ductor. The semi-conductive devices made by silicon have many advantages, for example, refractory pro- perty, high radioresistance, simple and stable process- ing technic, high machinability and low cost. So it was widely used to manufacture large power appara- tuses, for instance, digit and linear integrated circuit, large scale integrated circuit (LSI), etc. Thus, th…  相似文献   

6.
急性心肌梗塞患者血清硒,锌,铜,钙,镁,铁,锶含量的测定   总被引:4,自引:0,他引:4  
分别对29例急性心肌梗塞(AMI)病人和40例健康人进行血清中七种微量、常量元素含量测定,结果表明,AMI患者血清Se、Zn、Ca较正常对照组明显降低;血清Cu显著增高,血清Fe、Mg较对照组低,差异不显著;血清Sr两组无差异。对AMI患者与血清硒及各元素间相互关系进行了探讨,指出调整人体微量、常量元素的不平衡状况,对冠心病和AMI的发生、发展和康复有一定的临床意义。  相似文献   

7.
锌,铁,锰,铜,铅,镉,砷的示波极谱连续测定   总被引:1,自引:1,他引:1  
王河川 《分析化学》1989,17(2):192-192
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硫酸镍中Ca,Mg,Cu,Fe,Pb,Zn的光谱测定   总被引:2,自引:0,他引:2  
用发射光谱法测定结晶硫酸镍中Ca,Mg,Cu,Fe,Pb,Zn等杂质元素,加入NaCl为缓冲剂改善杂质元素的激发行为,以提高分析的灵敏度。用交流电弧激发,以镍为内标,一次摄谱,可同时测定上述六种元素。此法快速、准确,满足实际需要。  相似文献   

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钪-稀土-对乙酰基偶氮氯膦体系共显色效应的研究   总被引:1,自引:0,他引:1  
钪-稀土-对乙酰基偶氮氯膦体系共显色效应的研究刘双成,徐钟隽,潘教麦(华东师范大学化学系,上海,200062)关键词钪,稀土,对乙酰基偶氮氯膦,共显色效应不则称偶氮氯膦试剂与稀土元素的β型显色反应,已被广泛用于稀土的测定[1,2].但是当多种稀土或某...  相似文献   

12.
Terbium- and yttrium-group rare earths form β-complexes with CPApC in acidic medium.The sensitivities for determination of these rare earths by this reaction depend on their ionic radii.Cerium- or terbium-group rare earth in the presence of yttrium-group element produces the cocolourationeffect which remarkably sensitizes the reaction. Yb-CPApC-Eu complex has a molar composition of1:4:2 and gives a molar absorptivity of 2. 02 ×10~5 L·mol~(-1)·cm~(-1) at 746 nm for Eu. It is found thatthe closer the lengths of ionic radii of the rare earths are, the greater will be the cocolouration effect.  相似文献   

13.
本文研究了表面活性剂对1,5-二(2-羟基-5-氯苯基)-3-氰基甲(月朁)(HCPCF)及1,5-二(2-羟基-5-磺基苯基)-3-氰基甲(月朁)(HSPCF)以及其金属络合物吸收光谱的影响;通过对电泳、析相等现象的分析,探讨了HCPCF、HSPCF及其相应络合物反应行为的差别;讨论了胶束对络合反应速度的影响。  相似文献   

14.
Electron donor-acceptor (EDA) complex formation between o-chloranil and a series of anilines has been studied in CCl4 medium. In all the cases, EDA complexes are formed instantaneously on mixing the donor and acceptor solutions. N,N-dimethylaniline and N,N-dimethyl-p-toluidine form stable EDA complexes with o-chloranil while the other complexes decay slowly into secondary products. The kinetics of all these reactions has been studied by UV-VIS absorption spectrophotometric method and the rate constants of the reactions and formation constants of the EDA complexes have been determined. The charge transfer (CT) transition energies of the complexes are found to change systematically with change in the number and position of the methyl groups in the donor molecules (methylanilines). From an analysis of this variation, the electron affinity of o-chloranil has been found to be 2.54 eV. A perturbational inductive effect Hückel parameter hMe has been found from this trend and the value obtained (-0.27) is very close to that (-0.3) obtained by Lepley (J. Am. Chem. Soc., 86 (1964) 2545) from a study of tetracyano ethylene (TCNE)-methylbenzene complexes.  相似文献   

15.
The effect of alkyl chain length and electrolyte on the adsorption of sodium alkyl sulfate surfactants and the oppositely charged polyelectrolyte, polyDMDAAC, at the air-water interface has been investigated by surface tension and neutron reflectivity. The variations in the patterns of adsorption and surface tension behavior with alkyl chain length and electrolyte are discussed in the context of the competition between the formation of surface active surfactant/polyelectrolyte complexes and polyelectrolyte/surfactant micelle complexes in solution. A theoretical approach based on the law of mass action has been used to predict the surface effects arising from the competition between the formation of polyelectrolyte/surfactant surface and solution complexes and the formation of free surfactant micelles. This relatively straightforward model is shown to reproduce the principal features of the experimental results.  相似文献   

16.
The effect of charge transfer complex formation on the oxidisability of various phthalocyanines complexes with Lewis acids has been investigated. Multistep electron transfer between phthalocyanine as electron donor and the molecules of electron acceptor was found to be possible, leading to the formation of mono- and polycation radicals with characteristic magnetic properties. The structure of the transition products has been established and an oxidation mechanism is suggested.  相似文献   

17.
Kratochvil B  Tipler M  McKay B 《Talanta》1966,13(7):951-958
A potentiometric and spectrophotometric study has been made of the reaction between hexanitratocerate and picrate in dry acetonitrile. Several cerium(IV)-picrate complexes are formed; the formation constant for the first is estimated to be 4 from spectrophotometric measurements. The catalytic effect of picrate on hydroquinone oxidation by nitratocerate is postulated to be due to more rapid electron transfer by cerium picrate complexes.  相似文献   

18.
Complexation of rhodium compounds with phosphoryl-containing calix[4]resorcine in ethanol and acetone has been considered. The structure and properties of the synthesized complexes have been studied by IR and Raman spectroscopy, 1H and 31P NMR, EPR, UV-Vis spectroscopy, and TG/DSC. The effect of the solvent nature and conformation of a macrocyclic ligand on the structure of the resulting complexes has been observed. It has been demonstrated that one of the key factors responsible for complexation in EtOH is self-association of the ligand without the participation of the solvent. Complex formation in acetone is determined by its high ionizing ability. In diamagnetic complexes, the macrocyclic ligand is coordinated to the central atom through the phosphoryl oxygen atoms. For triaquatrichlororhodium in an aprotic medium, coordination occurs through the oxygen atoms of resorcinol moieties, which is accompanied by the formation of resorcinol radical anion and conversion of the diethoxyphosphorylaryl groups into ethoxyhydroxyphosphorylaryl moieties.  相似文献   

19.
Irving HM  Tomlinson WR 《Talanta》1968,15(11):1267-1279
In the determination of small amounts of copper in certain alloys by liquid-liquid extraction of the bis-chelate of copper(I) with 2, 2'-biquinolyl, recovery of copper has been reported to be low when chromium(III) is present. The adverse effect of chromium(III) could be overcome by adding iron(II). It is now shown that the inhibiting effect of chromium is attributable to the formation of a kinetically inert ternary complex of chromium(III), copper(II) and citrate ions containing an equal number of atoms of each of the two metals. Copper can be displaced from this complex by any of the transition cations Mn(II), Fe(II), Co(II), Ni(II) and Zn(II). Zinc is shown to form a ternary complex formally analogous to that of copper. The formation of the ternary complexes has been studied polarographically. The formation of binuclear complexes of various hydroxy-acids is reviewed and a probable structure for the ternary complex is proposed which explains its stability and kinetic inertness. Analogies are drawn between this complex and ternary complexes of UO(2)(VI)-Al(III)-citrate and Cu(II)-Al(III)-tartrate which also cause interference in established analytical procedures.  相似文献   

20.
林性如  刘春万 《结构化学》1993,12(4):307-311
<正> The electronic structures and bonding properties of the Mo-Cu-S complexes with a general formula [MoS4(CuCN)n]2-(n=1,2)have been investigated by using CNDO/2 method,and the effect of electron transfer on the formation of the Mo-Cu-S complexes has been discussed based on the bonding properties and the energy of the frontier orbitals.  相似文献   

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