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1.
高碘酸钾氧化溴甲酚紫动力学光度法测定间苯二酚   总被引:6,自引:0,他引:6  
在碱性和沸水浴条件下,微量的间苯二酚对高碘酸钾氧化溴甲酚紫褪色的反应具有显著的促进作用,据此建立了测定间苯二酚的新动力学光度法。该方法测定间苯二酚的线性范围为0.10~5.0μg/mL,检出限为0.041μg/mL,对于2.0μg/mL的间苯二酚11次测定的相对标准偏差是1.94%。方法用于皮炎宁酊及水样中间苯二酚的测定,结果满意。  相似文献   

2.
阻抑动力学光度法测定微量间苯二酚   总被引:10,自引:0,他引:10  
基于硫酸介质中 ,间苯二酚对 Fe( )催化 H2 O2 与罗丹明 B之间褪色反应的抑制作用 ,建立了一种测定微量间苯二酚的新方法 ,并研究了反应的最佳条件和动力学参数。该方法测定的线性范围为 0 .2 0~ 3.0 mg/L,ε564 =1 .3× 1 0 4L· mol-1· cm-1。可用于水样中间苯二酚的测定  相似文献   

3.
阻抑动力学光度法测定痕量间苯二酚   总被引:26,自引:3,他引:26  
黄志勇  陈国树 《分析化学》1998,26(11):1298-1302
研究发现,在硫酸介质中,Fe能催化H2O2与甲基红之间的裉色反应,加入间苯二酚后,间苯二酚又能灵敏地阻抑该氧化褪色反应,同时研究了该阻抑褪色反应的动力学条件,从而建立了一种新的测定痕量间苯二酚的方法。  相似文献   

4.
流动注射化学发光法测定水样中痕量间苯二酚   总被引:3,自引:0,他引:3  
基于在甲醛存在条件下,高锰酸钾在酸性介质中氧化间苯二酚而发生化学发光反应,建立了测定痕量的间苯二酚化学发光分析法.该法测定间苯二酚的线性范围为5.0×10-9~1.0×10-4mol/L,检出限为3.0×10-9mol/L,相对标准偏差为3.5%(1.0×10-6mol/L间苯二酚,n=11).该法应用于测定水样中加入的间苯二酚,结果令人满意.  相似文献   

5.
穆华荣  姚勇  颜朝国 《应用化学》2015,32(12):1416-1422
为深入开展杯芳烃为骨架的超分子拓扑结构的组装和性能,开展了间苯二酚杯芳烃八取代吡啶酰胺的合成和分子结构的研究。 以四丙基、四己基和四庚基间苯二酚杯芳烃为原料,使用α-氯乙酸甲酯实现O-烃基化,后者在无溶剂条件下与2-氨甲基吡啶反应实现酰胺化,制备了烷基间苯二酚杯芳烃八[N-(2-吡啶甲基)乙酰胺]衍生物。 用X衍射方法测定了四丙基间苯二酚杯芳烃八乙酸甲酯、四丙基以及四己基间苯二酚杯芳烃八[N-(2-吡啶甲基)乙酰胺]的单晶分子结构。 在晶体中,间苯二酚杯芳烃都以全顺式构型存在,在成环的四个间苯二酚单元中,1,3-位的两个间苯二酚单元处于近直立构象,2,4-位的另两个间苯二酚单元处于近平伏构象,而4个烷基皆处于分子的下缘,8个乙酰胺支链伸向分子的外围。  相似文献   

6.
阻抑动力学荧光法测定痕量间苯二酚   总被引:16,自引:0,他引:16  
王瑞勇  樊静  冯素玲 《分析化学》2000,28(8):968-970
基于在HClO4介质中,间苯二酚对Fe(Ⅲ)催化H2O2氧化罗丹明6G使其荧光猝灭的抑制作用,建立了动力学荧光法测定痕量间苯二酚的新方法。线性范围为0.008~0.096mg/L间苯二酚,方法检测限为5.9ug/L。用于测定合成样中间苯二酚的含量,结果令人满意。  相似文献   

7.
阻抑-褪色光度法测定痕量间苯二酚   总被引:8,自引:0,他引:8  
在NH3 NH4Cl介质中 ,间苯二酚能阻抑Fe(Ⅲ )为催化剂 ,邻菲罗啉为活化剂的过氧化氢氧化甲酚红的褪色反应。研究了该反应的最佳条件和动力学参数。建立了一种测定痕量间苯二酚的新方法。方法检出限为 3 5× 1 0 - 4 g·L- 1 ,测定范围为 0 .30mg/L~ 7.0mg/L ,方法可用于废水中间苯二酚的测定  相似文献   

8.
韩军  周瑞  颜朝国 《中国化学》2009,27(3):573-578
四烃基和四二茂铁基间苯二酚杯芳烃在丙酮回流条件和碳酸钾存在下用1-溴-3-氯丙烷或4-氯丁腈进行烃基化反应分别生成全取代的O-氯丙基和O-氰丙基间苯二酚杯芳烃,晶体结构测定表明烷基间苯二酚杯芳烃倾向于以全顺式构型存在,而芳基间苯二酚杯芳烃倾向于以顺-反-反式构型存在。本文还已经了四二茂铁基间苯二酚杯芳烃的电化学性质。  相似文献   

9.
基于酸性和沸水浴条件下,间苯二酚对高碘酸钾氧化鸡冠花红的反应具有显著的促进作用,据此建立了测定间苯二酚的动力学分析方法。该方法简单、快速,操作简便,线性范围为0.010~0.70 mg.L-1,检出限为0.008 7 mg.L-1,对于0.50 mg.L-1的间苯二酚测定11次的相对标准偏差为1.42%,应用于湖水和皮炎宁酊中间苯二酚的测定所得结果的RSD值小于4%,加标回收率大于97%。  相似文献   

10.
表面活性剂增敏催化光度法测定痕量铬(Ⅵ)   总被引:14,自引:0,他引:14  
报道了以十六烷基三甲基溴化铵为增敏剂,铬(Ⅵ)催化过氧化氢氧化间苯二酚蓝的反应,拟定了测定痕量铬(Ⅵ)的新催化光度法。本法由于添加了十六烷基三甲基溴化铵,灵敏度提高了19.8倍,测定铬(Ⅵ)含量的线性范围为0.02 ̄0.28mg/L,检出限为5.3×10^-3mg/L,相对标准偏差为1.1%(n=9),可用于水样中铬(Ⅵ)的测定。  相似文献   

11.
利用手持技术改进测定乙醇分子结构实验   总被引:1,自引:0,他引:1  
利用压强传感器代替排水集气法,改进测定乙醇分子结构实验的仪器装置,并探索最佳反应条件。另外,设计两个空白实验,结合压强变化曲线对实验误差进行相关讨论。  相似文献   

12.
13.
由于石化行业的生产需要,其材质的使用具有多样性和广泛性,经常会出现顾客委托的测试样品的一个或几个元素跨越光谱仪现有测试程序测量范围的情况。本法通过对光谱仪测试原理的认识,根据光谱仪的测试能力及标样的采集,实现了一个或几个元素测量范围的扩展,并对其测量的影响因素进行了研究。  相似文献   

14.
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   

15.
The oxygen quenching rate constants for singlet and triplet excited states of the dimethyl ester of mesoporphyrin IX increase with decreasing viscosity of the medium and reach a maximum at a viscosity of approximately 0.4 mPa·sec, after which the rate constants begin to decrease. The drop in rate constant with increasing fluidity of the medium may be related to a nonequilibrium character of the elementary act in the interaction of the reactants in the solvent cage. In viscous media such as isopropyl alcohol, isobutyl alcohol, and isoamyl alcohol, the reaction radius is greater than the sum of the radii of the reacting particles. The long-range character of these processes is due to the relatively weak dependence of the quenching probability on distance.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 161–167, March–April, 1989.  相似文献   

16.

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   

17.
实验教学目的是从解决实际问题出发,以实验技术训练和实验设计思想培养为目标。介绍了将单一的物质分配系数测定实验改进为综合实验,提高了实验效果及实验资源利用率。  相似文献   

18.
The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988.  相似文献   

19.
Sets of hydrogen molecule equivalents have been developed which permit the calculation of hydrogenation of different types of carbon-carbon bonds from ab initio total energies (3-21G and 6-31G* basis sets, and, to a more limited extent, for MP2/6-31G* data) of reactants and products. The calculated enthalpies of hydrogenation are in good agreement with experiment for unstrained molecules, with average errors on the order of 2 kcal/mol. The 6-31G* equivalents allow the enthalpies for strained molecules to be calculated accurately, but the 3-21G equivalents do not. The equivalents for both basis sets have been tested by calculating the enthalpies of hydrogenation of carbon-carbon bonds in nitrogen- and oxygen-containing organic molecules, free radicals, and classical carbocations. The results are in good agreement with experiment in most cases.  相似文献   

20.
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   

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