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1.
催化荧光动力学分析法的应用及其新进展   总被引:10,自引:0,他引:10  
唐波  韩芳  马骊 《分析化学》2001,29(3):347-354
催化荧光动力学分析法是用于检测痕量组分的有力手段。从检测催化剂及活化剂、多组分同时检测、酶催化、胶束在多组分同时检测及酶催化中的应用、结合流动注射及停流注射分析法及激光诱导荧光分析、时间分辨荧光分析、生物反应器控制、生物传感器、药物监测与生物分析等方面对催化荧光动力分析领域出现的新技术及新应用作一评述,并对今后的工作进行了展望。引用文献103篇。  相似文献   

2.
双Schiff碱过渡金属配合物和胶束形成的金属胶束作为模拟磷酸二酯水解酶用于催化BNPP水解,探讨了催化作用机理;提出了一种金属胶束催化BNPP水解的动力学数学模型。研究表明,本文所用的金属胶束在适当酸度、温度、介质的条件下对催化BNPP水解具有较高的活性。  相似文献   

3.
催化动力学分析法虽甚多,但具特色的方法极少,本文对两例方法作出评述. 1 胶束系催化动力学测定法  相似文献   

4.
研究了草酰胺桥联双核铜配合物和不同表面活性剂胶束组成的金属胶束催化PNPA水解的动力学特征。结果表明:金属胶束催化PNPA水解为双分子反应;不同配体结构的配合物的催化活性不同;三种不同类型表面活性剂胶束对催化PNPA水解的影响也不同。  相似文献   

5.
冠醚化Schiff 碱配合物金属胶束催化BNPP水解动力学   总被引:3,自引:0,他引:3  
研究了两种新的冠醚化Schiff 碱过渡金属配合物与表面活性剂Brij35(聚氧乙烯(23)十二烷基醚)形成的金属胶束对BNPP(对硝基苯酚磷酸二酯)的催化水解反应. 探讨了催化反应机理, 建立了一种金属胶束催化BNPP水解的动力学数学模型; 计算了模拟酶催化反应的相关参数和表观活化能. 结果表明, 此类金属胶束作为模拟水解金属酶对BNPP水解反应表现出良好的催化活性.  相似文献   

6.
陈一权  潘慰曾 《分子催化》1992,6(5):380-386
用温度跃升快速反应动力学测试仪器,研究了合成表面活性剂SDS胶束水溶液体系与生物表面活性剂脱氧胆酸钠(NaDC)胶束水溶液体系中,金属离子Ni~(2+)-2,2′-Bipyridine(Bipy)络合物形成的动力学。实验结果表明,生物表面活性剂同样表现出程度不同的胶束催化作用。又采用假相模型处理SDS胶束体系中上述反应的动力学,由动力学结果计算出可供发生反应的胶束体积。结果表明,此体积比不加电解质的胶束溶液中的反应体积增大,此现象被认为是由无机电解质的存在所造成。  相似文献   

7.
Schiff碱配合物催化过氧化氢氧化苯酚的动力学研究   总被引:3,自引:2,他引:1  
按照文献方法合成了钴(Ⅱ)和铁(Ⅱ)Schiff碱配合物,研究了它们作为模拟过氧化物酶在缓冲溶液中以及在三种不同的表面活性剂(CTAB,Brij35,LSS)胶束中催化过氧化氢氧化苯酚的反应,结果表明:过氧化氢/配合物物质的量比和胶束微环境对金属配合物催化过氧化氢氧化苯酚的反应有明显的影响;本文所提出的Schiff碱金属配合物催化苯酚氧化反应的机理和动力学数学模型是合理的。  相似文献   

8.
胶束催化2,4--二硝基氯苯碱水解反应动力学研究   总被引:3,自引:0,他引:3  
表面活性剂分子具有两亲基团,可在水溶液界面上发生吸附、定向排列以及在内部形成胶束等,因可明显地降低界面张力,因而具有调节润湿,增溶,乳化,洗涤,去污,起泡,消泡等功能,同时胶束的形成,还具有加快反应,提高反应专一性的作用[1].目前表面活性剂不仅广泛地应用于生产、生活的诸多领域,同时对交叉学科的发展也起着特殊的作用.其中由于胶束产生的局部浓集效应、静电效应和微环境效应等,不仅使一些在水溶液中难以进行的反应,如长链酯水解,高分子聚合等得以加速,同时还可模拟某些生物酶研究复杂的生理反应[2-4].研究并应用胶束的催化作用,已成为化学动力学十分活跃并有广泛应用前景的研究领域.但与此不相适应的是,基础物理化学实验中几乎没有相关的实验内容,为此本文研究了胶束催化2,4--二硝基苯碱水解反应动力学,论文内容可引入物理化学教学实验中.  相似文献   

9.
本文研究了上文提出催化光度测定硒的有关机理。非离子表面活性剂(NSF)对硒催化S~(2-)还原亚甲基蓝(MB)退色产生胶束催化作用。首先,MB与NSF形成带阳电的混合胶束(NSF-MB)。在此,MB增溶于NSF胶束的栅状层和聚氧乙烯外壳,然后,〔S…Se°〕~(2-)被吸附于此混合胶束的界面。由于增溶和吸附的双重富集作用,使胶束界面反应物的浓度大大提高,从而促进了反应速率。反应速度增加的大小,决定于形成NSF-MB混合胶束的难易(这又决定于NSF的憎水基的结构)及〔S…S°〕~(2-)和〔S…Se°〕~(2-)在此混合胶束界面吸附能力的大小。  相似文献   

10.
反胶束中的酶催化研究进展   总被引:18,自引:0,他引:18  
评述酶在反胶束中的定位和结构、动力学特性、催化活性和稳定性,反胶束作为酶催化反应介质的优点,反胶束中酶催化反应的类型及其应用。  相似文献   

11.
李明  陈焕文  刘志强  刘淑莹  金钦汉 《化学进展》2006,18(10):1369-1374
质谱动力学方法采用电喷雾离子化的方法获得含有手性化合物、并由过渡金属离子连接的复合物,然后进行碰撞诱导解离,两种解离途径的解离速率与混合物的对映体组成相关,进而可进行手性化合物光学纯度的测定。与其它常见手性测定方法相比,质谱动力学方法无需湿法化学处理和色谱分离步骤,操作简单、快速、灵敏,因而被广泛应用。本文对质谱动力学方法用于手性化合物对映体过量值测定的原理、改进方法、应用领域进行了评述。  相似文献   

12.
速差动力学分析及其应用进展   总被引:11,自引:2,他引:9  
方国桢  郭忠先 《分析化学》1993,21(11):1347-1354
速差动力学分析是不经分离同时或连续测定混合物中性质密切相关的多组份的重要方法。本文综述了该法在1989-1992年间国内外新进展,尤着重其在有机,生物混合物中多组份分析的应用及新的计算方法,化学计量学的引入。引用最新文献67篇。  相似文献   

13.
动力学拆分法的研究进展   总被引:1,自引:1,他引:0  
综述了光活性化合物动力学拆分法的研究进展及其在不对称合成中的应用。  相似文献   

14.
In this paper, a systematic analysis of the errors involved in the determination of the kinetic parameters (including the activation energy and frequency factor) from five integral methods has been carried out. The integral methods analyzed here are Coats-Redfern, Gorbachev, Wanjun-Yuwen-Hen-Zhiyong-Cunxin, Junmeng-Fusheng-Weiming-Fang, Junmeng-Fang and Junmeng-Fang-Weiming-Fusheng method. The results have shown that the precision of the kinetic parameters calculated by the different integral methods is dependent on u (E/RT), that is, on the activation energy and the average temperature of the process.  相似文献   

15.
A new integral method of nonisothermal kinetic analysis has been developed with the dependence of the frequency factor on the temperature (A = A 0 T m ). The new integral method is obtained from the newly proposed approximation for the general temperature integral, which is more accurate than the other existed approximations. For applications, nonisothermal thermoanalytical data obtained by theoretical simulation have been processed. The results have shown that the newly proposed integral method is an ideal solution for the evaluation of kinetic parameters from nonisothermal thermoanalytical data with the frequency factor dependent the temperature.  相似文献   

16.
倪永年  刘超 《分析化学》1999,27(5):596-603
化学计量学在动力学多组分分析中的应用是近年来非常活跃的领域。本文从多元校正、卡尔曼滤波、协同效应校正、人工神经网络及计算机应用等方面对化学计量学速差动力学分析领域出现的新方法及新动向作一评述,并对今后的工作进行了展望。引用文献99篇。  相似文献   

17.
A kinetic study and analytical applications of the CPC micellar catalyzed reactions of 1-fluoro-2,4-dinitrobenzene (FDNB) with inorganic thioanions (sulfide, sulfite and thiosulfafte) using a fluoride-selective electrode is described. Reaction orders (unity for both FDNB and thioanion) and experimental stoichiometric reaction-rate constants were calculated from initial slope measurements (DeltaE/Deltat) at various pH values (4-9). Calibration graphs for quantitative determinations (4.5-45 muM for sulfide, 2.4-75 muM for thiosulfate and 6.6-75 muM for sulfite) are constructed using the initial rate approach. The proposed method has been applied to the determination of sulfide in spiked seawater samples using the multiple standard addition approach with a mean relative error of 5.5%. The application of this micellar catalyzed reaction in the differential kinetic analysis of binary mixtures of sulfide-thiosulfate and sulfite-thiosulfate, using the proportional equations approach at pH 5.5 and 8.0, was unsuccessful due to the interactions of the two analytes, which can be explained using the ion-exchange/pseudophase model of micellar catalysis. However, the use of multiple linear regression approach on a sufficient number of standard binary mixtures can confront this drawback.  相似文献   

18.
Biaryl compounds with axial chirality are very common in synthetic chemistry, especially in catalysis. Axially chiral biaryls are important due to their biological activities and extensive applications in asymmetric catalysis. Thus the development of efficient enantioselective methods for their synthesis has attracted considerable attention. This Minireview discusses the progress made in catalytic kinetic resolution of biaryl compounds and chronicles significant advances made recently in catalytic kinetic resolution of biaryl scaffolds.  相似文献   

19.
This review describes chromatographic dispersion and different plate‐height models frequently used to assess the chromatographic performance of ultra‐high‐pressure liquid chromatography column technology. Furthermore, different performance indices, including the resolution, the separation impedance, and kinetic plots are discussed allowing to quantify and visualize the resolving power in liquid chromatography. The construction of kinetic plots is explained, and different visualization approaches are highlighted. Finally, key instrument and column‐technology developments to advance the kinetic performance limits are discussed and selected state‐of‐the‐art applications are highlighted.  相似文献   

20.
Binding constants between reactants molecules with micelles are considered to be important parameters particularly in micellar catalysis area. Recently, we developed a statistical method based on multiple linear regression for determining those parameters from kinetic data (Phys. Chem. Liq. 2008, 46, 34–46). In the present work, we derived further two statistical equations from the same original equation using also multiple linear regression method. A substantial difference has been found between the results of those equations and with that of the recently published one. This strongly indicates that the statistical procedures are not valid for such a purpose, that is, the available statistical and graphical methods in the literature are also not suitable for such treatment. A mathematical procedure using iterative method for evaluating the binding constants is introduced. An equation for such treatment has also been derived from the same original equation, and a computer program for this purpose has been written. Application of the developed method to the kinetic data has been found to be quite successful. It has been concluded that the presented mathematical method is simple, reliable, and accurate.  相似文献   

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