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1.
酸性镀铜体系的交流阻抗研究   总被引:6,自引:0,他引:6  
邓文  刘昭林 《电化学》1998,4(2):152-158
研究了基础溶液(0.3mol/LCuSO4+1.94mol/LH2SO4)以及添加60mg/LCl^-,300mg/LOP-21,30mg/LPEG-6000,10mg/L2-噻唑啉基-二硫丙烷酸钠(代号TDY,自合成添加剂)后体系的阻抗行为,结果表明:1)Cl^-在铜沉积中有增大阴极极化的作用;2)铜离子的放电为分步反应;即Cu^2+→Cu^+;Cu^+→Cu(吸附)→Cu(晶格),在含有Cl^  相似文献   

2.
KBrO3—KBr紫外分光光度法测定痕量水杨酸   总被引:5,自引:0,他引:5  
研究了HCl溶液中KBrO3-KBr紫外分光光度法测定水杨酸的条件,建立了测定痕量水杨酸的新方法。结果表明,在0.6mol/LHCl,3*10^-5mol/LKBrO3,5*10^-4mol/LKBr,6*10^-4mol/lKI溶中测定水杨酸,其线性范围为0.2-4.0mg/L,表观摩尔吸光系数为1.9*10^-4L.mol^-1.cm^-1,Sandell为7.3μg/cm^2。sg if e  相似文献   

3.
极谱法测定地质样品中痕量氯   总被引:7,自引:2,他引:7  
提出了0.1%HCOOH-8×10^3%百时香酚兰,-0.4mol/LHClO4-0.4%TritonX-100极谱法痕量氯离子的新体系,检出限为0.18μg/g,RSD为7.6%,标准样品测定结果与推荐值相吻合。  相似文献   

4.
极谱催化波法测定黄连素   总被引:5,自引:0,他引:5  
宋俊峰  何盈盈  过玮 《分析化学》2000,28(12):1538-1541
基于黄连素在过氧化氢存在下产生的极谱催化波,拟定了测定黄连素的新方法。在8.0×10-2mol/LNa2B4O7-Na2CO3(pH9.4±0.4)-4.0×10-3mol/LH2O2底液中,催化波峰电流与黄连素浓度在 1.0 × 10-8~ 3.0 × 10-7mol/L范围内呈线性关系。催化波的灵敏度比相应黄连素还原波高25倍。  相似文献   

5.
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   

6.
氢化物发生ICP-AES法测定药用植物中的痕量锗   总被引:6,自引:0,他引:6  
本文应用氢化物发生ICP-AES法研究了药用植物样品中痕量锗的测定方法,系统地研究了ICP-AES仪器参数及氢化物发生条件对锗谱线信背比的影响,考察了13种共存元素的干扰,并比较了植物样品的3种前处理方法。选定H3PO4-HNO3-H2O2消化,在3mol/LH3PO4介质中,以15g/LNaBH4还原,测定药用植物样品中的锗,相对标准偏差≤2.9%,回收率为94%~103%。方法检出限达0.13μg/L。  相似文献   

7.
在0.2mol/LNaOH-0.04mol/LH3PO4-0.02mol/L(NH4)2SO4-0.04mol/LCH3COOH溶液中,精氨酸(Arg)在苯甲醛存在下产生一灵敏的吸附波。实验证明电活性物质为α-苯亚甲基精氨酸,其电极反应机理是分子内α->C=N基团被还原为亚胺。用该吸附波可在1×10(-3)~2×10(-6)mol/L范围内分析蛋白质中的Arg。  相似文献   

8.
葡萄糖脱氢酶微型生物传感器的研制及应用   总被引:3,自引:0,他引:3  
习玲玲  施清照 《分析化学》1998,26(9):1093-1096
以甲苯胺兰(TB)修饰碳糊微电极为基体,将葡萄糖脱氢酶(GDH)用丝素蛋白膜固定于修饰微电极表面制成了生物传感器,在pH7.0的NaOH-NaH2PO4缓冲溶液中,烟酰胺腺嘌呤二核苷酸(NAD)的浓度为1.04×10^-3mol/L的条件下,其响应电流与葡萄糖浓度在1.0×10^-4~3.2×10^-3mol/L范围内有良好线性关系,响应时间为20s;检测限为4.0×10^-5mol/L。该传感器  相似文献   

9.
本文报道了一个灵敏度高,选择性好的测定痕量钍的新光度分析法。在聚乙烯醇存在下,钍钼杂多酸和丁基罗丹明B形成离子缔合物,其适宜条件为CHClO4=1.3MOL/L,CMoO^2-4=6.8×10^-4mol/L,CBRB=2.7×10^-5mol/L,PVA0.08%。  相似文献   

10.
锗(Ⅳ)-邻苯二酚紫-钒(Ⅳ)体系的极谱吸附催化波研究   总被引:5,自引:0,他引:5  
在0.1mol/LH2SO4溶液中,Ge(Ⅳ)-邻苯二酚紫(PV)-V(Ⅳ)体系产生一灵敏的吸附催化波,峰电位在-0.55V(vs.SCE)处.锗浓度在2.2×10-10~2.8×10-6mol/L范围内与峰电流呈线性关系.检出限为1.1×10-10mol/L.研究了极谱波的性质.本法用于土壤中痕量锗的测定,结果满意.  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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