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1.
盐酸环丙沙星的示波极谱测定及其机理研究   总被引:5,自引:0,他引:5  
在PH6.9的KH2PO4-KOH缓冲液中,盐酸环丙沙星在滴汞电极上产生一灵敏的催化氢波。峰电位为-1.51V,在1.00×10^-7-2.00×10^-5mol.L^-1之间有良好的线性关系,用于对盐酸环丙沙星的测定,方法简便、结果准确可靠。  相似文献   

2.
示波极谱法测定微量锰   总被引:2,自引:0,他引:2  
研究了在氨-氯化铵介质中,Mn(Ⅱ)与邻菲罗啉形成络合物并在示波极谱仪上产生一灵敏的吸附还原波的适宜条件和影响因素,建立了测定微量锰的新方法。测定线性范围为5.0×10^-8 ̄5.0×10^-6mol·L^-1,检出下限为2.0×10^-8mol·L^-1,测定了水和酒样中的锰含量,结果满意。  相似文献   

3.
示差脉冲伏安法测定黄酒中的酪氨酸   总被引:3,自引:0,他引:3  
本文研究了硼砂介质中镍与酪氨酸络合物的示差脉冲吸附伏安特性,实验了仪器参数对示差脉冲阴极吸附伏安法的影响,在最佳条件下络合物峰电流与酪氨酸浓度在2.0×10^-7~4.0×10^-5mol.L^-1范围内有线性关系,并以此法测定了黄酒中酪氨酸的含量。  相似文献   

4.
吴绍祖  方文焕 《分析化学》1995,23(11):1247-1251
本研究了一个高灵敏的测定镉的方法,离心光度法,该体系络合物λmax=560nm,表观摩尔吸系数ε560=5.06×10^8L.mol^-1.cm^-1,Cd^2+浓度0.10×10^-2-1.0×10^-2μg/10mL呈线性关系,本法已用于血清和水中痕量镉的测定,探讨了高灵敏的显色反应机理。  相似文献   

5.
含有吸附络合物溶液的倒数示波计时电位法的应用   总被引:3,自引:0,他引:3  
Pb(Ⅱ)在0.2%乙二胺-5×10^-3mol·L^-1HOx-0.3mol·L^-1KOH溶液中,有良好的全数示波图,其峰电位Ep=-1.05(vs.SCE),峰高与Pb^2+溶度在4.0×10^-7~2.0×10^-5mol·L^-1内成正比,检测下限可达2.0×10^-7mol·L^-1。本实验采用倒数示波计时电位法对铝合金“A”中铅进行了测定,并直接通过示波图,对络合物的吸附属于性进行了  相似文献   

6.
胆红素的间接光度测定   总被引:1,自引:0,他引:1  
郑玉霞  曾百肇 《分析化学》1993,21(10):1159-1161
本文研究了在pH10的氨-氯化铵溶液中铜对胆红素的催化氧化作用及其氧化产物胆绿素与铜形成络合物的性质。该络合物在340nm波长处有最大吸收,可用于对胆红素的间接光度测定。其线性范围为1.2×10^-6~3.0×10^-5mol/L。  相似文献   

7.
络合吸附波极谱法测定稀土钢中微量稀土   总被引:2,自引:0,他引:2  
研究了在pH9.2-pH9.5的NH30Na2B4O7介质中,稀土与百里香酚酞的络合物极谱波,波高与镧量在4.0×10^-7-3.6×10^-6mol/L范围内成线性关系。方法已用于稀土钢中微量稀土的测定。  相似文献   

8.
迭代目标转换因子分析光度法同时测定钯,铑   总被引:3,自引:0,他引:3  
王英华  周桂霞 《分析化学》1993,21(11):1317-1319
钯,铑二元素于HAc-NaAc缓冲介质中,在表面活性剂Triton X-100存在下与5-Br-PADAP形成灵敏度较高的紫红色络合物,其摩尔吸光系数分别为ε565^pd=1.44×10^5,ε562^Rh=1.17×10^5(L·mol^-1·cm^-1)。二元素络合物吸收光谱发生严重重叠。本文探讨了在上述体系中同时测定Pd,Rh的最佳条件,并采用迭代目标转换因子分析法(ITTFA)对Pd,Rh  相似文献   

9.
李益恒  朱志伟 《分析化学》1995,23(9):1069-1072
本研究了锡(Ⅳ)-3,4-二羟基苯甲酸络合物的相敏交流吸附溶出行为,在PH3.6的甲酸盐缓冲溶液中,该络合物经两步双电子还原在相敏交流伏安图上于-0.33V和-0.49产生两个吸附还原波,第一个波更灵敏,峰电流与锡浓度在1.7×10^-9-2.5×10^-7mol/L范围内呈线性关系,检测限达4×10^-10mol/L。测得络合物组成的1:1。方法已应用于罐头食品中锡的测定。结果满意。  相似文献   

10.
以偶合反应流动注射化学发光法测定铅   总被引:15,自引:0,他引:15  
李卫华  张小清 《分析化学》1998,26(2):219-221
基于Pb(Ⅱ)能置换出Fe(Ⅱ)-EDTA络合物中的Fe(Ⅱ)和Fe(Ⅱ)-鲁米诺-溶解氧产生化学发光的反应,建立了置换偶合反应流动注射化学发光测定痕量铅的新方法。本方法线性范围1×10^-7 ̄1×10^-5g/mL,相对标准偏差为2.5%(n=11,C=10^-6g/mL),检出限为2×10^-8g/mL。用于污水中铅的测定,结果令人满意。  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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