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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   

3.
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   

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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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7.
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   

8.
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   

9.
ICP—AES法测定钢铁样中硅,磷,锰,铬,镍,铜,铝   总被引:7,自引:0,他引:7  
详细地研究了钢铁样中主量铁对7种被测定元素的干扰和被测定元素间的干扰情况,并研究了不同酸分解样品的效果,确定了用电感耦合等离子体发射光谱测定钢铁样中硅、磷、锰、铬、镍、铜和铝的方法。  相似文献   

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The functional group capacity and the percentage of functional group conversion of crosslinked polystyrene resin bearing N-methyl-2-thioimidazole (MTIR) synthesized under optimum conditions are as high as 4.08 mmol/g resin and 96.0%, respectively. The apparent activation energies of sorption of MTIR for Au(III) and Pt(IV) are 13.1 and 13.4 kJ/mol, respectively. The sorption behavior of MTIR for Au(III), Pt(IV), and Pd(II) obeys the Freundlich and Langmuir isotherms. The sorption capacities of MTIR for Au(III), Pt(IV), and Pd(II) are as high as 4.33, 2.12, and 2.33 mmol/g resin, respectively. Au(III), Pt(IV), and Pd(II) adsorbed on MTIR can be eluted quantitatively by the eluant. The resin can be regenerated easily and reused without an obvious decrease in the sorption capacity for Au(III) and Pd(II). The resin has high sorption selectivity for noble metal ions. Au(III) can be separated quantitatively in the presence of high concentrations of Cu2+, Fe3+, Ni2+, and Mn2+. The recovery of platinum from the spent industrial catalysts is 98.6% by MTIR. The preconcentration and separation of palladium and platinum from the anode deposits of electrolysis of crude copper have been investigated. The resin may have potential industrial uses.  相似文献   

12.
由聚[2′-氯乙基-2,3-环硫丙基醚]和多乙烯声胺反应,合成了四种以聚硫醚为主链的氧杂多乙烯多胺型螯合树脂,它们对贵金属离子Au(Ⅲ)、Pd(Ⅱ)、Pt(Ⅳ)、Ag~+等具有优良的吸附性能。  相似文献   

13.
A method for rapid simultaneous neutron activation determination of Pd, Au, Pt and Ir in USGS standard rocks, ores and minerals has been developed based on selective extraction of determined elements. Results of determination of noble metals in standard rocks are discussed.  相似文献   

14.
Su ZX  Pu QS  Luo XY  Chang XJ  Zhan GY  Ren FZ 《Talanta》1995,42(8):1127-1133
A new functional resin with a long functional side chain was synthesized by modification of aminated macroporous poly(vinyl chloride) resin with cyanoethylene and ethylenediamine. Traces of Au(III), Pt(IV) and Pd(II) in aqueous solution were quantitatively adsorbed in the acidity range of pH 4 and C(H(+)) 3 M. The rate of equilibration is high; Cu(2+), Fe(3+), Ni(2+), etc. exhibit little interference on the adsorption of the sought noble metals. The saturated adsorption capacities for Au(III), Pt(IV), Pd(II) and Ir(IV) in 2 M HCl were 4.0, 1.57, 2.26, 1.85 mmol g(-1). Adsorbed ions can be quantitatively desorbed by 4% thiourea +0.25 M H(2)SO(4). The resin has good reusability, and can be used for preconcentration and separation of Au(III), Pt(IV) and Pd(II) prior to their determination by ICP-AES with satisfactory results.  相似文献   

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本文报道了以多乙烯多胺为主链的巯基胺树脂与二硫化碳反应,合成了四种新型的氨基二硫代甲酸型螯合树脂,这类树脂对贵金属具有高的吸附容量和优良的吸附选择性。并通过红外光谱和X光电子能谱研究树脂及其金属螫合物。  相似文献   

17.
本文报道了一种合成硫杂冠醚聚合物的新方法。以聚(2′-氯乙基-2,3-环硫丙基醚)为预聚物与二巯基化合物通过大分子反应直接环化,一步法合成了四种以聚硫醚为主链的新型硫杂冠醚聚合物(PD1-PD4)。并测定了它们对Ag~+、Au~(3+)、Pd~(2+)、Pt~(4+)、Cu~(2+)、Hg~(2+)、Zn~(2+)、Cd~(2+)、Pb~(2+)、Mg~(2+)、K~+、Ns~+等金属离子的络合性能。结果表明:它们除不络合K~+、Na~+、Mg~(2+)、Pb~(2+)外,对其它八种离子有不同程度的络合,其中对Ag~+、Au~(3+)、Pd~(2+)等贵金属离子的络合容量较高。  相似文献   

18.
Di P  Davey DE 《Talanta》1995,42(5):685-692
A flow injection on-line microcolumn method has been studied for the separation and preconcentration of noble metals, Pd, Pt and Ir, followed by flame AAS determination. An alpha-amino pyridine resin was used as preconcentration reagent. Non-noble metals studied could be eliminated by 2M HCl solution in the rinsing stage. A group-eluent for all Pd, Pt and Ir was studied. Separation of individual noble metals could also be accomplished using selective eluents. This approach can be used both for the separation and determination of Pd, Pt and Ir in samples. The sensitivities and the sample frequency have been improved. The method has been applied to certified samples.  相似文献   

19.
利用密度泛函理论系统研究了贵金属原子(Au、Pd、Pt和Rh)在CeO2(111)表面的吸附行为。结果表明,Au吸附在氧顶位最稳定,Pd、Pt倾向吸附于氧桥位,而Rh在洞位最稳定。当金属原子吸附在氧顶位时,吸附强度依次为Pt > Rh > Pd > Au。Pd、Pt与Rh吸附后在Ce 4f、O 2p电子峰间出现掺杂峰;Au未出现掺杂电子峰,其d电子峰与表面O 2p峰在-4~-1 eV重叠。态密度分析表明,Au吸附在氧顶位、Pd与Pt吸附在桥位、Rh吸附在洞位时,金属与CeO2(111)表面氧原子作用较强,这与Bader电荷分析结果相一致。  相似文献   

20.
用螯合树脂对金属进行分离富集及测定,前人已做了许多有意义的研究[1~4].曾用含键合S双硫腙(P-D)和脱氢双硫腙(P-DT)功能团的离子交换树脂和螯合树脂分离金和铂族金属[5],用双硫腙负载树脂分离富集Cu(Ⅱ)[6]。  相似文献   

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