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1.
氧化还原酶催化合成芳香聚合物的研究进展   总被引:2,自引:0,他引:2  
主要概括了近年来以典型的氧化还原酶包括辣根过氧化物酶,大豆过氧化物酶和漆酶等催化合成苯酚,双酚,蒽醌类聚合物,苯胺类聚合物,聚苯醚等聚芳香族功能高分子材料的研究进展,并对多酶法与化学酶法的酶促合成作了介绍。  相似文献   

2.
用分子沉积自组装作制备了阳离子化和阴离子化的辣根过氧化物酶自组装膜;并用原子力显微镜(AFM)研究了不同离子化辣根过氧化物酶单层及多层自组装膜的形貌结构与自组装膜的活性变化关系。结果表明:阴离子化的辣根过氧化物酶自组装膜的表面形貌比较粗糙,均方根粗糙度(RMS)及酶分子粒径较大,且组装膜的活性比较大。  相似文献   

3.
辣根过氧化物酶在亲水性离子液体中的活性与稳定性研究   总被引:3,自引:2,他引:1  
基于辣根过氧化物酶对过氧化氢氧化愈创木酚这个显色反应的催化作用,研究了辣根过氧化物酶在七种亲水性离子液体[C2mim][BF4]、[C4mim][BF4]、[C6mim][BF4]、[C4mim]HSO4、[C4mim]Cl、[C4mim]NO3、[C4mim][CF3CO2]中的活性与稳定性变化.结果表明辣根过氧化物酶在不同离子液体中均有不同程度的失活,辣根过氧化物酶活性随离子液体极性增强而降低.辣根过氧化物酶在含[C4mim]Cl离子液体的介质中,随着温度升高,[C4mim]Cl对辣根过氧化物酶的失活过程起加速作用,离子液体浓度越高,酶的热稳定性越差.紫外-可见光谱研究表明,在含[Cnmim][BF4]、[C4mim]HSO4、[C4mim]Cl、[C4mim]NO3的介质中,辣根过氧化物酶血红素中心最大吸收峰没有发生变化,但吸收值增强,证明离子液体使酶的血红素基团暴露于介质中而增强了吸收;而在含[C4mim][CF3CO2]的介质中,辣根过氧化物酶血红素基团最大吸收峰区发生蓝移,证明有部分血红素基团被离子液体破坏而脱落.  相似文献   

4.
利用对辣根过氧化物酶催化体系的干扰测定左旋多巴   总被引:5,自引:2,他引:3  
朱敏  黄雪梅 《分析化学》1997,25(8):930-933
提出辣根过氧化物酶法分析左旋多巴,方法基于一定条件下左旋多巴对辣根过氧化物酶催化对氯苯酚-4-AAP偶联发色体系有干扰,干扰程度与左旋多巴的有浓度有相关性。  相似文献   

5.
反相微乳液中辣根过氧化物酶催化反应的研究   总被引:2,自引:0,他引:2  
研究了辣根过氧化物酶(HorseradishPeroxidase,HRP)在AOT/水/异辛烷微乳液中的多底物酶促反应行为.实验结果表明,反相胶束中动力学反应机制与纯水中不同,并且利用紫外可见光度法研究了中间化合物Ⅲ在2种不同介质中的稳定性.  相似文献   

6.
辣根过氧化物酶在分析化学中的应用   总被引:12,自引:0,他引:12  
辣根过氧化物酶是一种重要的分析化学试剂,对过氧化氢底物特异性强。广泛用于临床化学、环境化学和食品工业等领域。本文评述了近十年来辣根过氧化物酶在分析化学中的应用进展。包括光度法、荧光法、化学发光法、电化学传感器和光导纤维传感器法测定过氛氢及相关物质,及辣根过氧化物酶在其他无机、有机及生物物质分析中的应用。引用参考文献60篇。  相似文献   

7.
水相中辣根过氧化物酶的反应动力学和机理研究   总被引:4,自引:0,他引:4  
陈建波  夏春谷 《分子催化》2000,14(2):125-128
利用分光光度法 ,对水相中辣根过氧化物酶与底物反应的最适反应条件进行了研究 .同时 ,用停流法探讨了 2 5℃时辣根过氧化物酶反应过程中各种中间化合物的形成和消失速度 ;并用停流光谱法对稳态动力学的研究结果进行了验证  相似文献   

8.
辣根过氧化物酶分光光度法测定黄嘌呤氧化酶的活性   总被引:15,自引:0,他引:15  
研究了以辣根过氧化物酶-苯酚-4-氨基安替比林反应显色新体系,检测黄嘌呤氧化酶(XOD)活力的新方法。确定该酶活性测定的最佳条件为:辣根过氧化物酶(HRP)7000 U/L,4-氨基安替比林(AAP)1 mmol/L,苯酚(PA)6 mmol/L,黄嘌呤(XAN)1 mmol/L溶于50 mmol/L Tris-CL缓冲液(pH 8.4);反应温度为37℃,保温时间为20 m in;检测波长为508 nm。本方法测定XOD酶活的线性范围为5.0~100.0 U/L,线性关系良好(r=0.9992),检出限为1.3 U/L。该方法操作简单易行,测定结果准确可靠。可有效应用于普通实验室和临床常规生化检测。  相似文献   

9.
本文通过β-环糊精与环氧氯丙烷反应,合成了交联预聚物,进而在酸性条件下与戊二醛和辣根过氧化物酶反应,从而把辣根过氧化物酶固定在所形成的聚合物绝缘体基底上.应用扫描电化学显微镜的反馈模式,研究了辣根过氧化物酶的催化反应动力学.通过对扫描电化学显微镜在酶点上的反馈曲线与理论曲线的拟合,测得了一级反应速率常数,并用此方法研究了pH对反应速率常数的影响.在pH=7.0时,辣根过氧化物酶的活性最高,与文献报道一致,结果满意.  相似文献   

10.
氯化血红素作为过氧化物模拟酶与HRP的比较研究   总被引:5,自引:0,他引:5  
用荧光光谱和紫外-可见吸收光谱研究了氯化血红素(hemin)催化过氧化氢与对羧基苯丙酸反应的动力学和反应产物,表明hemin同时具有模拟过氧化物酶、过氧化氢酶的活性,在反应过程中hemin自身被氧化分解。hemin催化反应的产物除与天然的辣根过氧化物酶(HRP)催化的产物相同(λex/λem=310nm/406nm)外,还有激发峰在258nm和300nm,发射峰在360nm的荧光物质。通过对产物光谱特性的比较,研究了hemin和HRP的特异性差异。该研究结果对进一步筛选和研究高特异性过氧化物模拟酶具有重要的指导意义。  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

13.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。  相似文献   

16.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

17.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

18.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

19.
袁丽秋 《化学教育》2006,27(5):8-10
面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。  相似文献   

20.
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