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1.
阻抑动力学分光光度法测定痕量碘   总被引:7,自引:0,他引:7  
研究了在稀H3PO4介质中,痕量碘离子对NO-2催化溴酸钾氧化吖啶橙的阻抑作用,建立了测定痕量碘离子的阻抑动力学光度分析的新方法。测定碘离子的线性范围为0~0.40μg/mL,检出限为7.3×10-9g/mL。已用于食品中的微量碘的测定。  相似文献   

2.
阻抑-催化褪色动力学光度法测定食盐中的微量碘   总被引:5,自引:0,他引:5  
在KH2PO4-K2HPO4介质中,微量碘(I-)对过氧化氢氧化碱性藏花红褪色反应有抑制作用,据此,建立了阻抑催化褪色动力学光度测定痕量碘的方法。该法的线性范围为0~40μg/L,检出限为1.6×10-8g/L。本法用于食盐中微量碘的测定,分析结果满意。  相似文献   

3.
阻抑动力学分光光度法测定微量碘   总被引:1,自引:0,他引:1  
基于在稀磷酸介质中,痕量碘离子对亚硝酸根催化溴酸钾氧化甲基红的的阻抑作用,提出了测定痕量碘离子的阻抑动力学分光光度分析的方法.测定碘离子的线性范围在0.66 mg·L-1以内,检出限(3Sb/K)为7.5×10-6g·L-1.用于海带及食盐中微量碘的测定,测定结果的相对标准偏差(n=6)在1.4%~2.2%之间,测得方法的回收率为99.7%~100.1%.  相似文献   

4.
研究了在稀硫酸介质中,痕量碘离子对亚硝酸根催化溴酸钾氧化甲酚红的阻抑作用,建立了测定痕量碘离子的阻抑动力学光度分析的新方法。测定碘离子的线性范围为0~0.62μg/mL,检出限为7.43×10-9 g/mL。已用于食品中痕量碘的测定,结果满意。  相似文献   

5.
阻抑动力学光度法测定痕量间二硝基苯   总被引:2,自引:1,他引:2  
在盐酸介质中,痕量间二硝基苯能灵敏地阻抑Fe^3 催化高碘酸钾氧化孔雀绿的反应。研究了该阻抑反应的最佳条件及动力学参数,建立了测定痕量间二硝基苯的新方法,间二硝基苯的线性范围为0.0-10.0μg/L,检出限为1.8μg/L。该法灵敏、简便,选择性好,用于环境水样中间二硝基苯的测定,结果准确。  相似文献   

6.
阻抑动力学荧光光度法测定苯胺   总被引:11,自引:0,他引:11  
程定玺  张红武 《分析化学》2002,30(6):719-721
在醋酸介质中,痕量苯胺对溴酸钾和过氧化氢氧化罗丹明6G使其荧光猝灭的反应有抑制作用,据此建立了阻抑动力学荧光法灵敏测定痕量苯胺的新方法。方法检出限为0.50μg/L,测定范围为8.40-58.7μg/L。方法用于环境废水中苯胺的测定,结果令人满意。  相似文献   

7.
阻抑动力学光度法测定环境水样中的痕量苯酚   总被引:2,自引:1,他引:2  
基于在稀硫酸介质中,痕量苯酚能灵敏地阻抑高碘酸氧化苯胺蓝褪色,研究了该阻抑褪色反应的最佳条件及动力学参数,建立了测定痕量苯酚的新方法。该方法的线性范围为0-40.0μg/L,线性回归方程为1g(A1/A2)=0.638c 0.00117,相关系数r=0.9996,检出限为1.2μg/L。该方法简便,灵敏,选择性好,用于环境水样中痕量苯酚的测定,结果准确。  相似文献   

8.
阻抑动力学光度法测定水中痕量苯胺   总被引:2,自引:0,他引:2  
基于KH2PO4-Na2HPO4缓冲介质中,痕量苯胺对高碘酸钾氧化维多利亚绿反应有阻抑作用,建立了一种测定痕量苯胺的催化动力学的新方法。该方法的线性范围为0~100μg/L,检出限为2.0×10-6g/L。已用于废水中苯胺的测定。  相似文献   

9.
阻抑动力学光度法测定食品中的痕量铜   总被引:4,自引:1,他引:3  
研究了铜阻抑高碘酸钾氧化玫瑰桃红R的褪色反应 ,建立了阻抑动力学光度法测定痕量铜的新方法 ,找到了最佳试验条件。该法线性范围为 0~ 0 0 0 8μg/mL ,检出限为 0 3 9× 1 0 - 3μg/mL ,应用于食品中铜的测定 ,结果满意  相似文献   

10.
阻抑动力学光度法测定芦丁的研究   总被引:4,自引:1,他引:3  
在稀硫酸介质中,微量芦丁对高碘酸钾氧化玫瑰桃红R褪色反应有明显的阻抑作用,据此建立了测定微量芦丁的动力学光度新方法。选定了最佳条件并测定了反应动力学参数,方法的线性范围为0.02~0.4μg mL,检出限为5.0×10-9g mL。方法已用于槐米和芦丁片剂中芦丁的测定。  相似文献   

11.
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   

12.
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   

13.
Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position.  相似文献   

14.
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   

15.
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   

16.
The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of hematite Fe2O3. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the best fitting experimental data. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

17.
Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6.  相似文献   

18.
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   

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.

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   

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