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1.
宋俊峰  高雅芳 《分析化学》1995,23(4):438-441
本报道一种测定哌仑西平的单扫描示波极谱法,在0.1mol/LNH4Cl-NH3.H2O(pH8.0±0.1)缓冲液中,哌仑西平有一极谱还原波,其峰电位为-1.51V(vs.SCE),其一阶导数峰高与哌仑西闰浓度在6.6×10^-7-4.6×10^-6mol/L(r=0.9981)和6.6×10^-6-1.6×10^-5mol/L(r=0.9991)范围内有线性关系,检测限为3.4×10-7mol  相似文献   

2.
在0.01mol/LNH.H2O-NH4Cl和3.0×10^-5mol/L安息香缩氨基硫脲体系中,钴产生一灵敏的还原波,其峰电位是-0.94V(vs.SCE),峰电流与钴的浓度在2.0×10-8-1.0×10^-6mol/L范围内成直线关系,检测限为5.0×10^-9mol/L,该法测定水中痕量钴结果令人满意。  相似文献   

3.
乳酸环丙沙星单扫描示波极谱法研究   总被引:3,自引:0,他引:3  
研究了乳酸环丙沙星的极谱伏安行为,在pH=8.3的0.02mol/L,NH4Cl-NH3.H2O底液中,乳酸环丙沙星能产生1个灵敏的还原峰,峰电位为-1.61V,其导数峰高与浓度在3.9×10^-8~1.8×10^-6mol/L和1.8×10^6~1.1×10^-5mol/L范围内呈现良好的线性关系,相关系数r=0.9997,检测下限为2.5×10^-8mol/L,用于乳酸环丙沙星注射液的测定,相  相似文献   

4.
过氧化物模拟酶催化的苯基荧光酮氧化反应及其分析应用   总被引:4,自引:0,他引:4  
郭忠先  沈含熙 《分析化学》1998,26(12):1451-1455
在NH4Cl-NH4OH缓冲介质中,氯化血红素(Hemin)有显著的过氧化物模拟酶活性,催化过程化氢氧化苯基荧光酮褪色。本文探讨了反应机理,比较Hemin与天然酶催化性能,考察反应条件和共存物质影响,从而提出测定Hemin和过氧化氢的高灵敏分光光度法,线性范围分别为0 ̄3.0×10^-8mol/L和0 ̄1.2×10^5mol/L;检测限(3σ)分别为1.8×10^-10mol/L和1.4×10^7  相似文献   

5.
王桂芬  朴元哲 《分析化学》1998,26(12):1490-1493
应用循环伏安法、微分脉冲伏安法对多菌灵在破碳电极上的电化学行为及其测定进行了研究。在pH=9.0的2mol/L NH3-NH4Cl底液中,对其进行循环伏安扫描,发现于0.61V(vs.Ag/AgCl)产生一灵敏的氧化峰。微分脉冲伏安法殉菌灵的检测限为4×10^-8mol/L。多菌灵的浓度在5.0×10^-7 ̄1.0×10^-5mol/L间与微分脉冲伏安峰电流呈线性关系(r=0.9942)。对于1×  相似文献   

6.
本报导了以玻碳电极为基体的1∶12硅钼杂多阴离子薄膜化学修,铈电极的制备及其电化学特性。并应用于导数伏安法测定。在4.0×10^-3mol/L9NH4)6Mo7O24-66.8×10^-2mol/LNa3Cit-0.48mol/L NHO3体系中,硅浓度在8.3×10^-7~1.7×10^-3mol/L。对可溶性硅(以SiO2计)为245.05mg/L的黑液,稀释10倍后,取2.00mL平行测定  相似文献   

7.
于泳  毛燕宁  李启隆 《分析化学》1999,27(5):562-565
抗癌药物紫杉醇在0.2mol/L NH3-NH3-NH4Cl中,采用单扫示波极说法进行测定,形成一良好的还原峰,峰电位Ep=-1.45V(vs.SCE)。峰电流与紫杉醇的浓度在1.0×10^-7 ̄8.0×10^-6mol/l之间呈线性关系;检测限为5.0×10^-8mol/L,并将此方法应用于样品测定。用线性扫描和循环伏安法研究体系的性质,结果表明,紫杉醇的电极过程属于具有吸附性的准可逆过程。  相似文献   

8.
铜(Ⅱ)和锌(Ⅱ)分别在0.1mol/LKH2PO4-Na2HPO4缓冲溶液(pH6.5)和0.25mol/LNH4Cl溶液中,与氟哌酸形成良好的络合吸附波,峰电位分别为-0.26V和-1.28V(vs.SCE),络合比分别为1:3和1:2,峰电流与铜(Ⅱ)和锌(Ⅱ)的浓度均在4.0×10^-7~5.0×10^-6nol/L范围内呈线性关系,检测限分别为7.0×10^-8和5.0×10^-8mol  相似文献   

9.
头孢噻肟钠的降解及其产物伏安行为的研究   总被引:18,自引:1,他引:18  
头孢噻肟钠在NaOH溶液中降解后,于0.1mol/LNaOH中得一灵敏的吸附伏安原峰,Ep=-0.78V(νsAg/AgCl),ip与头孢噻肟钠浓度在1.0×10^-^9-1.0×10^-^8,1.0×10^-^8-1.0×10^-^7,1.0×10^-^7-1.0×10^-^6mol/L范围内呈线性关系,检出限为5.0×10^-^1^0mol/L。用多种电化学手段研究其降解产物的伏安行为,测定了  相似文献   

10.
姚德  刘辉 《分析试验室》1994,13(6):68-71
在0.2mol·L^-1NH4Cl-NH3·H2O底液中,(pH为9.26),得到一个极为灵敏的Fe(Ⅲ)-TEA-5-Br-PADAP-H2O2配合吸附催化波,其峰电位为-0.71V(vs.SCE)。铁浓度在1.8×10^-10 ̄5.4×10^-6mol·L^-1范围内与二阶导数波高呈线性关系。对该极谱波的性质进行了研究,证明是一种配合吸附催化波,并成功地应用于各类水样,钒催化剂中微量或痕量铁的  相似文献   

11.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

12.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

13.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

14.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

16.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

17.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

18.
19.
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).  相似文献   

20.
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.  相似文献   

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