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31.
A new method for indirect determination of captopril (CPT) with NaNO3 and NH4SCN by floatation and separation of copper has been studied. In the weak acid, a small amount of Cu(II) can be reduced to Cu(I) by CPT, then Cu(I) reacted with the SCN, which can float on the surface of the liquid phase with NaNO3. A good linear relationship is observed between the floatation yield (E%) of Cu(II) and the amount of captopril. The linear range is 2?32 mg/L. On the ground, captopril can be indirectly determined by determining E(%) of Cu(II). The method is simple, rapid, reliable and has good selectivity. The developed method can be applied to indirect determination of captopril with satisfactory results. 相似文献
32.
The reductive alkylation of amine with carbonyl compounds usingsodium hydrogen telluride has been investigated in recent years.Application of this method to the synthesis of N-alkyl derivativesof biologically important amino acids and their esters is described. 相似文献
33.
Study of Tea Digitized Chromatographic Fingerprint Spectra Using Micellar Electrokinetic Chromatography 总被引:1,自引:0,他引:1
IntroductionTeaisthemostwidelyconsumedbeverageinpeople’slife .Theheightenedpopularityofthisbeveragethroughouttheworldinrecentyearsmaybedueinparttotheevidenceofarelationshipbetweenteaconsumptionandpreventionofcertainformsofhumandisease .Themaincomponentsofteaarepolyphenoliccompounds ,commonlyknownascatechins ,whichrepresentagroupofcom poundsbelongingtotheflavonoidfamily .Thesecom poundsarewidelydistributedinthetealeavesandconsti tuteupto 30 %ofthedryleafweight.1Muchinteresthasbeenfocusedoncat… 相似文献
34.
高效液相色谱法测定血浆中7种灭鼠剂 总被引:12,自引:0,他引:12
建立了血浆中7种缓效灭鼠剂的反相高效液相色谱分析方法,选择了样品提取与测定条件,考察了有关化合物对测定的影响,在色谱工作站上建立了灭鼠剂的紫餐吸收光谱库,根据吸收光谱与tR值进行库检索,提出了定性的准确度。方法的线性范围为2-10μL/L血浆,最低检测浓度为1μL/mL血浆。 相似文献
35.
A new method for the synthesis of eight-membered heterocyclic 1,4,5-oxadiazocines has been described from β-diketone and β,β,β-triketone with an acidic α-hydrogen. The method entails the reaction of a di- or triketone with 2-hydroxyethylhydrazine and an aldehyde in the presence of acetic acid providing respectable yield. 相似文献
36.
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38.
Ma DL Shum TY Zhang F Che CM Yang M 《Chemical communications (Cambridge, England)》2005,(37):4675-4677
Platinum(II) terpyridine complexes with glycosylated acetylide and arylacetylide ligands bind to DNA with binding constants approximately 10(5) mol(-1) dm(3); the glycosylated arylacetylide complexes exhibit emission at lambda(max) approximately 620 nm in water and are up to approximately 100-times higher in potency than the clinical cisplatin drug in killing cancer cells. 相似文献
39.
Xian Zhao Daren Guan Xizhang Yi Guibao Xu Minhua Jiang 《International journal of quantum chemistry》2003,93(5):335-343
A dynamic Lie algebraic (DLA) formulation is applied to the study of nonlinear optical properties of the substituted benzenes. We have described the generation of the dynamic Lie algebra for the model Hamiltonian used in the present study. In terms of these elements of the dynamic algebra we express the evolution operator as a function of the group parameters, which can be determined by means of solving a system of coupled nonlinear differential equations. Thus, in terms of the density matrix operator formalism in statistical mechanics we obtain the statistical averages of the electric polarization and then derive readily an expression for the hyperpolarizability of the paradisubstituted benzenes. Comparisons with experimental observations and other quantum calculations of the hyperpolarizabilities for the paradisubstituted benzenes are made qualitatively and quantitatively. These results imply that the DLA method appears useful in describing the nonlinear optical phenomena in the substituted benzene molecules. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem 93: 335–343, 2003 相似文献
40.
Jingqi Guan ShuBo Jing Shujie Wu Haiyan Xu Zhenlv Wang Qiubin Kan 《Reaction Kinetics and Catalysis Letters》2007,90(1):27-33
A series of MoV0.3Tex (x = 0−0.3) mixed oxides were prepared and investigated for the selective oxidation of isobutane. Among them, MoV0.3Te0.23 showed the best methacrolein and methacrylic acid selectivity (as high as 17% and 16%, respectively), and the yield to methacrolein
and methacrylic acid reached 3.6% and 3.5%, respectively, at 21.3% isobutane conversion at 440°C. 相似文献