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1.
甲苯胺蓝修饰石墨电极为基体的乙醇脱氢酶生物传感器   总被引:3,自引:0,他引:3  
施清照  张培敏 《分析化学》1997,25(6):690-692
报道了电流型乙醇生物传感器。该传感器以甲苯胺蓝键合修饰浸蜡石墨电极为基体电极,将醇脱氢酶、烟酰胺腺嘌呤二核苷酸(NAD^+)同时固定在蚕丝蛋白膜上,成为无试剂的醇传感器。在pH8.5的Tris-HCl介质中,该传感器的响应电极与乙醇浓度在5.0×10^-5 ̄1.10×10^-3mol/L范围内有良好的线性关系。响应时间为20s。本文讨论了影响传感器响应的各种因素。用该传感器测定了啤酒中乙醇的含量,  相似文献   

2.
甲苯胺蓝修饰石墨电极为基体的乙醇脱氨酶生物传感器   总被引:1,自引:0,他引:1  
报道了电流型乙醇生物传感器。该传感器以甲苯胺蓝键合修饰浸蜡石墨电极为基 体电极,将醇脱氢酶、烟酰胺腺嘌呤二核苷酸(NAD+)同时固定在蚕丝蛋白膜上,成为无试剂 的醇传感器。在 pH 8. 5的 Tris-HCl介质中,该传感器的响应电流与乙醇浓度在 5. 0× 10-5~ 1.10×10-3mol/L范围内有良好的线性关系。响应时间为20s。本文讨论了影响传感器响应 的各种因素。用该传感器测定了啤酒中乙醇的含量,结果与气相色谱法一致。  相似文献   

3.
用脉冲色谱峰加宽非稳态法测定乙醇在Pt/Al2O3催化剂中400-480℃之间的有效扩散系数。乙醇孔扩散活化能为5.46kJ/mol。当用0.45-0.60mm催化剂时,乙醇的完全氧化在动力学区域进行、氧分压过量时,此区域的反应速率遵循乙醇0.1级速度方程。  相似文献   

4.
研究了经ZrO2改性的Cu/ZnO/Al2O的催化性能,考察了操作条件,ZrO2含量及不同原料的影响,发现经共沉淀法制备了Cu/ZnO/Al2O3/ZrO2具有最佳的反应活性及选择性以95%乙醇为原料,在265℃,WHSV1.5h^-1,乙醇转化率为69.0%,乙酸乙酯选择性为70.2%,使用无水乙醇为原料要好地95%乙醇,使用乙醛或醇醛混合原料,亦有乙酸乙酯生成,乙醇在此催化剂上的反应机理为乙醇  相似文献   

5.
微生物电极法测定啤酒中乙醇含量   总被引:1,自引:1,他引:1  
用自制的乙醇微生物电极建立了一种测定啤酒中乙醇含量的新方法。该法具有良好的精密度和准确度,其测定结果与比重瓶法和气相色谱法相一致,回收率为97.3%-104.9%。该电极线性范围为0.3-12.0mg/L,60天测定600余次,其灵敏度基本稳定。测试的最适酸度范围为pH6.4-7.3,温度为32-34℃,测定一个样品需5-8min。  相似文献   

6.
过硫酸钾存在下人血清白蛋白的极谱平行催化氢波及其应用   总被引:10,自引:0,他引:10  
报道 K2S2O8存在下人血清白蛋白(HSA)的极谱平行催化氢波。在 0.4 mol/L NH3-NH4Cl(pH 8.58)-0.01 mol/L K2s2O8支持电解质中,HSA产生一个平行催化氢波,峰电位为-1.85 V(vsAg/AgCl)。该平行催化氢波二阶导数峰电流与 HSA浓度在 2.6 × 10-9~9.6 × 10-9mol/L范围呈线性关系。用于人血清样和尿样中HSA的测定,结果满意。  相似文献   

7.
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   

8.
聚邻苯二胺修饰电极抗坏血酸氧化酶生物传感器的研究   总被引:6,自引:0,他引:6  
本文报道了聚邻苯二胺/抗坏血酸氧化酶生物传感器,用这种传感器测定人体血清中的抗坏血酸,线性范围在1.0×10^-4~2.5×10^-7mol/L之间,响应时间为7s,检测限为1.0×10^-8mol/L。该传感器具有选择性好、灵敏度高和响应时间短等特点。  相似文献   

9.
多波长叠加近红外吸收光谱法直接测定酒精饮料中的乙醇   总被引:17,自引:0,他引:17  
利用乙醇在1382nm,1691nm和1730nm处的吸光度值,采用多波长叠加近红外吸收光谱法测定乙醇的含量。结果表明,乙醇在0%~24%(V/V)浓度范围内呈良好的线性关系;回归方程为: A= 0. 01754+ 0. 04747C;相关系数r=0. 9994。用该法可直接测定葡萄酒、啤酒和黄酒中乙醇的含量,6次平行测定的RSD分别为;葡萄酒4.0%,啤酒2.5%,黄酒2.4%。回收率为97.5%~105.0%,本方法具有操作简便,准确和快速等优点。  相似文献   

10.
张光  张林林 《分析化学》1997,25(1):79-81
报道以5-(5-硝基-2-吡啶偶氮)-2,4-二氨基甲苯(5-NO2-PADAT_作为测定钌的分光光度法。在40%乙醇存在下PH4.0-6.5乙酸-乙酸钠缓冲溶液中5-NO2-PADAT与Ru(Ⅱ)形成稳定的红色络合物。该络合物的无机酸作用下,可转变为另一型人有较高吸收特性的络合物,适宜酸度范围分别为0.12-2.0mol/LHCl,0.12-1.2mol/LHClO4,0.12-1.0mol/L  相似文献   

11.
Transforming renewable lignin into high value-added chemicals is a forward-looking strategy to address the resource waste caused by insufficient utilization of biomass resources. On this basis, studying the efficient conversion of lignin to aldehydes/acids and their reaction mechanisms has become an attractive topic. A systematic investigation of the gas-phase oxidation reaction mechanisms of the three model compounds initiated by O2 was carried out at the atomic and molecular levels by using density functional theory (DFT). Further revealing of oxidation behavior on two reaction sites of phenolic hydroxyl group and hydroxymethyl group were accomplished in detail. The potential energy surface information of 21 possible reaction channels of two pathways were obtained at B3LYP/6-311+G(d,p) level. The influence of substituent effects on the reaction energy barrier was estimated. The calculation results showed that the reactivity of phenolic hydroxyl group is stronger than that of hydroxymethyl group, because the reaction Gibbs potential barriers are lower by about 4.9–8.7 kcal/mol. The reaction energy barriers on phenolic hydroxyl group site and hydroxymethyl group site decrease with the increase of the number of methoxy groups. Revealing the oxidation processes of lignin model compounds will provide a deeper understanding on the reaction mechanism and provide theoretical support for further experimental research on the conversion of lignin into high value-added chemicals.  相似文献   

12.
李志铭  贾瑜  周景尧 《化学学报》2000,58(10):1301-1306
在金属镝的促进下,醛、酮可与炔丙基溴反应,高选择性高产率地得到相应的高炔丙醇,没有发现连二烯醇的存在。当用苯基炔丙基溴代替炔丙基溴与醛、酮反应时,主要得到了相应的连二烯醇,而没有发现高炔丙醇的存在,由此提出了六元环过渡态的反应机理。  相似文献   

13.
According to experimental and literature data, the one-pot formation of allylic azides or sulfonamides from catalytic amounts of PdCl2, homoallylic alcohols and TMSN3 or TsNH2 occurs through CC migration followed by regioselective nucleophilic addition on the PdII-activated CC bond and β-OH elimination.  相似文献   

14.
The reaction of easily available Morita–Baylis–Hillman (MBH) alcohols with AgSCF3 in the presence of n-Bu4NI and KI affords primary allylic SCF3 products in high yields and excellent regioselectivities. This regioselective dehydroxytrifluoromethylthiolation protocol could also be extended to propargylic alcohols for the preparation of the primary propargylic SCF3 products.  相似文献   

15.
以锆盐为交联剂的耐盐型聚乙烯醇高吸水树脂的合成   总被引:6,自引:0,他引:6  
以锆盐为交联剂的耐盐型聚乙烯醇高吸水树脂的合成刘德荣,颜杰,刘习奎,刘兴勇(四川轻化工学院化学工程系自贡643033)关键词聚乙烯醇锆盐络合树脂,耐盐型聚乙烯醇吸水树脂,磷酸化聚乙烯醇本研究采用两种方法在聚乙烯醇中引人磷酸根.(l)聚乙烯醇和磷酸反应...  相似文献   

16.
A complete study of the asymmetric addition of phenylacetylene to ketones catalyzed by Schiff-base amino alcohol-Zn complex is reported in this article. The Schiff-base amino alcohols were easily prepared from amino acids in three steps. When the amount of ligand was 1%(molar fraction), an e.e. value up to 94% was obtained. A series of practical chiral ligands were applied in the enantioselective addition of phenylacetylene to ketones without adding another stronger Lewis acid except zinc.  相似文献   

17.
磷钼酸盐作为反应控制相转移催化剂催化氧化醇   总被引:1,自引:0,他引:1  
翁志焕  王锦艳  刘志勇  蹇锡高 《化学学报》2007,65(11):1081-1084
以磷钼酸盐[C7H7N(CH3)3]3{PO4[MoO(O2)2]4}为反应控制相转移催化剂, 用过氧化氢水溶液为氧化剂, 在液相选择性氧化醇制备醛的反应中, 发现该催化剂具有良好的催化活性. 在H2O2与醇的物质的量比为0.75的条件下, 产物中未检测到任何副产物, 基于H2O2的醇转化率最高达到95.2%. 反应结束时, 催化剂以沉淀的形式析出, 回收率不低于78%. 以苯甲醇的氧化为探针反应, 详细考察催化剂的反荷阳离子和溶剂种类对反应控制相转移现象和催化活性的影响. 结果表明, 选择 [C7H7N(CH3)3]作为反荷阳离子和乙腈为溶剂, 体系出现了反应控制相转移催化的特征. 催化剂循环使用三次, 在保持较高回收率的同时其催化活性无明显降低, 说明该催化剂具有良好的稳定性.  相似文献   

18.
We report a general method for the indium-mediated Barbier-type enantioselective allylation of both aromatic and aliphatic aldehydes using commercially available (1S,2R)-(+)-2-amino-1,2-diphenylethanol as a chiral auxiliary. Using only two equivalents of allyl bromide, excellent yields and very good to excellent enantioselectivities are obtained. To our knowledge, the enantioselectivities reported herein are the highest obtained for indium-promoted allylations of carbonyl compounds.  相似文献   

19.
本文应用三乙胺催化聚合丙炔醇。研究了该聚合反应的特征及动力学行为。制得带有光泽的褐色粘性固体产物,聚丙炔醇显示半导体及顺磁特性。  相似文献   

20.
Alcohol use disorder (AUD) affects over 18 million people in the US. Unfortunately, pharmacotherapies available for AUD have limited clinical success and are under prescribed. Previously, we established that avermectin compounds (ivermectin [IVM] and moxidectin) reduce alcohol (ethanol/EtOH) consumption in mice, but these effects are limited by P-glycoprotein (Pgp/ABCB1) efflux. The current study tested the hypothesis that dihydromyricetin (DHM), a natural product suggested to inhibit Pgp, will enhance IVM potency as measured by changes in EtOH consumption. Using a within-subjects study design and two-bottle choice study, we tested the combination of DHM (10 mg/kg; i.p.) and IVM (0.5–2.5 mg/kg; i.p.) on EtOH intake and preference in male and female C57BL/6J mice. We also conducted molecular modeling studies of DHM with the nucleotide-binding domain of human Pgp that identified key binding residues associated with Pgp inhibition. We found that DHM increased the potency of IVM in reducing EtOH consumption, resulting in significant effects at the 1.0 mg/kg dose. This combination supports our hypothesis that inhibiting Pgp improves the potency of IVM in reducing EtOH consumption. Collectively, we demonstrate the feasibility of this novel combinatorial approach in reducing EtOH consumption and illustrate the utility of DHM in a novel combinatorial approach.  相似文献   

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