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1.
在pH2.5的盐酸-邻苯二甲酸氢钾缓冲溶液中,得到锑-茜素紫配合物的单扫极谱吸附波。峰电位在-0.41V(vs.SCE),锑(Ⅱ)浓度在1.6×10~(-8)~7.4×10~(-7)mol/L间与导数峰高成正比。用拟定的方法测定样品,获得了满意结果。本文对极谱波性质、配合物组成和电极过程进行了探讨。  相似文献   

2.
在 5 .0× 1 0 - 6 mol/LSe(Ⅳ )的 0 .1 2mol/L氯乙酸盐缓冲溶液 (pH 3 2 )中 ,用单扫极谱法可得到锑 (Ⅲ ) 芦丁络合物灵敏的二次导数极谱波 ,Se(Ⅳ )的存在可使锑峰峰电位正移 ,峰高增加。峰电位为 - 0 .33V(vs.SCE) ,峰高与锑(Ⅲ )的浓度在 1 .6× 1 0 - 9mol/L~ 5 .0× 1 0 - 6mol/L范围内呈线性关系 ,检出限可达 4.0× 1 0 - 1 0 mol/L。研究了极谱波的性质和电极反应机理。方法已用于锌合金中微量锑的测定  相似文献   

3.
在8×10~(-3)mol/L NaOH-0.2mol/L KClO_3底液中,Pb(Ⅱ)-QBTU体系产生灵敏的阴极化二阶导数波,峰电流与铅浓度在4.0×10~(-8)~4.5×10~(-6)mol/L范围内有良好的线性关系。本文对电极过程,反应机理,极谱波的性质进行了详细的探讨。  相似文献   

4.
建立了硅锑钼三元杂多酸体系导数极谱测定微量硅的新方法。在0.6mol/L硫酸-20%乙醇介质中,于55℃时,硅(Ⅳ)、锑(Ⅲ)和钼(Ⅷ)形成具有电活性的硅锑钼三元杂多酸;在0.3 mol/L硫酸-10%乙醇介质中,于-0.47V(vs. SCE)处产生一灵敏的还原峰,其二阶导数电流峰高与硅的浓度在6.8×10~(-9)~7.4×10~(-7)mol/L范围内呈线性关系,检出限为4.3×10~(-9)mol/L,应用于水样及矿石中硅的测定,结果满意。  相似文献   

5.
铋-N-苯甲酰苯胲络合吸附波的研究   总被引:1,自引:0,他引:1  
在pH5.6的0.2mol/L NH_4Ac-3×10~(14)mol/L N-苯甲酰苯胲(N-BPHA)底液中,用单扫示波极谱法可得到Bi(Ⅲ)的络合物吸附波,峰电位-0.33V(vs.SCE)左右。导数峰高与铋的浓度在5.0×10~(-8)~4.0×10~(-6)mol/L的范围内呈线性关系,检出限为2.0×10~(-8)mol/L。实验表明,该极谱峰属于络合物吸附波,测定其络合比为Bi(Ⅲ):N-BPHA=1:3。测定了该体系的吸附量;Bi(Ⅲ)-N-BPHA络合物在悬汞电极上的吸附符合Frumkin等温式,测得吸附系数β=2.87×10~5,吸引因子α=0.984。用于矿石中微量铋的测定。  相似文献   

6.
本文研究了在0.01mol/L NaOH—0.32%乙二胺—0.05mol/L酒石酸钾钠介质中,锰与4-(2-噻唑偶氮)间苯二酚(TAR)络合吸附波的极谱行为。当介质中含有0.003%TAR时,Mn会产生灵敏的导数极谱波,其峰电位为-0.75V(相对银汞齐电极,下同),方法检出限为1.5×10~(-9)mol/L,线性范围为3.6×1.0~(-9)mol/L~2.7×10~(-6)mol/L。研究了极谱波的性质、机理以及络合物的组成。方法成功地应用于某些植物叶中微量锰的含量测定。  相似文献   

7.
在0.08 mol/L磷酸溶液中,锑(Ⅲ)-邻苯三酚红络合物产生一灵敏的吸附波,加入硫脲对峰高有增敏作用.峰电位在-0.30 V(vs.SCE)左右,峰高与锑浓度在4.1×10-10~2.1×10-6 mol/L间呈线性关系;检出限为2×10-10 mol/L.并进行了机理研究.方法应用于铜合金中锑的直接测定,结果满意.  相似文献   

8.
在HCl-NaAc介质(pH 2.5)中,用单扫示波极谱法可获得高灵敏的In(Ⅲ)-2-疏基苯骈噻唑(MBT)-7-碘-8-羟基喹啉-5-磺酸(Ferron)三元络合物吸附波.峰电位在—0.64V(vs.SCE),峰电流与铟浓度在7.0×10~(-10)mol/L~8.8×10~(-7)mol/L之间呈线性关系.检出限可达3.0×10~(-10)mol/L.测得电活性络合物的组成为In(Ⅲ):MBT:Ferron=1:1:1.研究了极谱波的性质和机理.本法选择性较好,用于工业废水和地下水中痕量铟的测定,结果满意.  相似文献   

9.
在0.2mol/L柠檬酸三钠的缓冲介质中(pH10.5—11.7)有0.02%的α-安息香肟存在下,铜(Ⅱ)产生一个灵敏的络合物吸附波。峰电位-0.60V(vs.SCE),峰电流与铜(Ⅱ)浓度在6.3×10~(-7)—1.9×10~(-5)mol/L范围内呈线性关系,检测限6.3×10~(-8)mol/L。本文探讨了该极谱波的性质,并测定了络舍比为1:1,可直接用于测定铝合金中的铜,方法简单,快速、灵敏并获得满意的结果。  相似文献   

10.
铕(Ⅲ)-钙试剂络合物吸附波及其应用研究   总被引:2,自引:0,他引:2  
用线性扫描极谱法研究了在氨-氯化铵缓冲体系中Eu(Ⅲ)-钙试剂络合物的极谱行为。在pH10.2的NH3-NH4Cl缓冲介质中,Eu(Ⅲ)-钙试剂络合物在-0.82V(vs.SCE)处有一灵敏的导数极谱波,其峰电流与Eu(Ⅲ)的浓度在1.0×10-7~8.0×10-6mol/L范围内呈线性关系,检出限为9.0×10-8mol/L。方法可用于试样中痕量铕的测定。本文还研究了极谱波的性质。  相似文献   

11.
Two new complexes (Cp)2Ti(Sal)2 and(Cp)2Ti(Clo)2(Cp=Cyclopentadienyl η5-C5H5), have been synthesized in anhydrous THF by the reaction of Hsal(o-hydroxybenzoic acid, salicylate acid) or Hclo[N-(m-chloro-phe-nyl) anthranili acid, acidum clofenamicum] with (Cp)2TiCl2 and characterized by means of elemental analyses, IR, 1H NMR, 13C NMR, UV and molar conductivity. In complex (Cp)2Ti(Sal)2 or (Cp)2Ti(Clo)2, the oxygen atom of the carboxyl group coordinates to Ti(IV) in a monodentate manner. The inhibitory action of the complexes on mouse ear tumefaction caused by croton oil and rat foot granulation growth caused by cotton balls is higher than that of the corresponding ligands Hsal, Hclo and [(Cp)2TiCl2], whereas their toxicity is lower than those of the free ligands.  相似文献   

12.
13.
The measured Raman and IR spectra of solid, polycrystalline bis(pentamethylcyclopentadienyl)dizinc, (eta(5)-C5Me5)2Zn2, 1, and bis(pentamethylcyclopentadienyl)monozinc, (eta(5)-C5Me5)(eta(1)-C5Me5)Zn, 8, are reported in some detail. The IR spectra of the vapors of 1 and 8 each trapped in a solid Ar matrix at 12 K confirm the essentially molecular character of the solids. The experimental results have been interpreted with particular reference (i) to the corresponding spectra of (68)Zn-enriched samples of the compounds, and (ii) to the spectra simulated by density functional theory (DFT) calculations at the B3LYP level. The marked differences of structure of 1 and 8 contrast with the relatively close similarity of their vibrational spectra, disparities being revealed only on detailed scrutiny, including the effects of (68)Zn enrichment, and primarily at wavenumbers below 1000 cm(-1). The Zn-Zn stretching motion of 1 features not as a single, well-defined mode identifiable with intense Raman scattering but in several normal modes which respond in varying degrees to (68)Zn substitution. A stretching force constant of 1.42 mdyne A(-1) has been estimated for the Zn-Zn bond of 1.  相似文献   

14.
The reaction of Na[η5-C5H5Fe(CO)2] with large excess of SO2 in THF at ?78°C followed by warming to room temperature affords an iron—dithionite complex, (η5-C5H5)(CO)2FeS(O)2S(O)2Fe(CO)25-C5H5).  相似文献   

15.
Conclusions The photochemical reactions of (CO)2(PPh3)MnC5H4Fe(CO)2C5H5 and (CO)2(PPh3)MnC5H4COFe(CO)2C5H5 with PPh3 gave the products of replacing the CO on the Fe atom by PPh3: respectively (CO)2(PPh3)MnC5H4Fe (CO)(PPh3)C5H5 and (CO)2(PPh3)MnC5H4COFe(CO)(PPh3)C5H5.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2813–2815, December, 1977.  相似文献   

16.
《Tetrahedron letters》1987,28(27):3059-3060
The synthesis of mevalonolactone stereospecifically labeled at carbon 5 is described combining chemical reactions with an enzymatic reduction step.  相似文献   

17.
In this study, (51)V, (45)Sc and (93)Nb MAS NMR combined with satellite transition spectroscopy analysis were used to characterize the complex solid mixtures: VNb(9(1-x))Ta(9x)O(25), ScNb((1-x))Ta(x)O(4) and ScNb(2(1-x))Ta(2x)VO(9) (x = 0, 0.3, 0.5, 0.7, 1.0). This led us to describe the structures of Sc and V sites. The conclusions were based on accurate values for (51)V quadrupole coupling and chemical shift tensors obtained with (51)V MAS NMR/SATRAS for VNb(9)O(25), VTa(9)O(25) and ScVO(4). The (45)Sc NMR parameters have been obtained for Sc(2)O(3), ScVO(4), ScNbO(4) and ScTaO(4). On the basis of (45)Sc NMR and data available from literature, the ranges of the (45)Sc chemical shift have been established for ScO(6) and ScO(8). The gradual change of the (45)Sc and (51)V NMR parameters with x confirms the formation of solid solutions in the process of synthesis of VNb(9(1-x))Ta(9x)O(25) and ScNb((1-x))Ta(x)O(4), in contrast to ScNb(2(1-x))Ta(2x)VO(9). The cation sublattice of ScNb((1-x))Ta(x)O(4) is found to be in octahedral coordination. The V sites in VNb(9(1-x))Ta(9x)O(25) are present in the form of slightly distorted tetrahedra. The (93)Nb NMR parameters have been obtained for VNb(9)O(25).  相似文献   

18.
Reaction between gadolinium(III) and 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5- Br-PADAP) was studied for delineating optimal conditions for complexation. This reagent can be used for the spectrophotometric determination of Gd(III) in concentrations ranging from 0.04 to 1.2 ppm (a = 1.76(+/- 0.03) x 10(5) (1.(-1) mole(-1). cm). The reaction takes place at a pH between 9.2 and 11.6. In the presence of Triton X-100 this complex is soluble in water. In order to overcome difficulties caused by the presence of other lanthanides, an ion exchange chromatographic technique was used.  相似文献   

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