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关键词： analytical methods   ethyl carbamate   formation pathways   genotoxicity   mitigation strategies  

摘要： Ethyl carbamate (EC) commonly found in fermented beverages has been verified to be a multisite carcinogen in experimental animals. EC was upgraded to Group 2A by the Intl. Agency for Research on Cancer (IARC) in 2007, which indicates that EC is a probable carcinogen to humans. Because of its threat to human safety, the presence of EC may be a big challenge in the alcoholic beverage industry. During the past few years, thorough and systematic research has been carried out in terms of the generation of EC in order to meet the allowed limitation levels in fermented beverages. Previous studies have indicated that EC primarily results from the reaction of ethanol and compounds containing carbamyl groups. These main EC precursors are commonly generated from arginine metabolism by Saccharomyces cerevisiae or lactic acid bacteria accompanied by the fermentation process. This review comprehensively summarizes the genotoxicity, analytical methods, formation pathways, and removal strategies of EC in various beverages. The article also presents the metabolic mechanism of EC precursors and pertinent metabolites, such as urea, citrulline, and arginine.

关键词： ANALYTICAL chemistry -- Study & teaching   ORGANIC chemistry -- Study & teaching (Higher)   PHYSICAL & theoretical chemistry   STUDY & teaching (Higher)  

摘要： While there are references to the practice of chemical analysis in ancient Chinese times, the modern system of analytical chemistry was introduced into China in the late 19th century. Thanks to the Chinese chemist Shou Xu, who translated several chemical books from western countries, including two important books on analytical chemistry: Manual of Qualitative Chemical Analysis [1] and Quantitative Chemical Analysis [2]. The Chinese titles of the translated books were HUAXUE KAOZHI and HUAXUE QIUSHU. These two books, together with other books translated later by Chinese scientists, became the key textbooks for chemical analysis. For a long time, however, all textbooks related to the analytical chemistry in China were translated from western countries. Almost no textbooks on analytical chemistry were written by Chinese professors until the 1930s.

关键词： Second-Year Undergraduate   Analytical Chemistry   Laboratory Instruction   Hands-On Learning/Manipulatives   Acid Base   Titration/Volumetric Analysis  

摘要： The formation and the hydrolysis of organic salts produced by the titration of a 0.1 M solution of the following amines: methyl-, dimethyl-, trimethyl-, ethyl-, diethyl-, and triethylarnine with a 0.1 M solution of acetic, chloroacetic, and dichloracetic acids are studied. The pK(b) of the amine and the pH at the end point were determined for each reaction from the corresponding titration curve. The experimentally determined values were in very good agreement with the literature and calculated values. The salt formation constants (K-sf) for acetate and mono- and dichloroacetate salts of primary, secondary, and tertiary methyl- and ethylamines were also determined. The conclusions were as follows: (1) the pH at the end point decreased as the strength of the titrating acid increased, (2) the stronger the amine base, the higher the pH at the end point, and (3) the K-sf increased with increasing acid and base strength.

关键词： Chemical fingerprinting   Tussilago farfara   Hierarchical clustering analysis   Characteristic peaks  

摘要： The aim of this study was to establish a method for extraction and chemically fingerprinting of extracts of Tussilago farfara and to apply this method to 12 T. farfara samples collected from different regions in China. RP-HPLC with gradient elution was performed on rutin. Comparing with the chromatograms, it showed that the samples were divided into two groups. Thirteen characteristic peaks were found in the extracts of all samples. Peak at retention time of 17.45 min was identified as rutin. Hierarchical clustering analysis showed the similar results as the visual comparison. The RP-HPLC method allowed it simple to identify and compare T. farfara. This was the first report on hierarchical clustering analysis of T. farfara.

关键词： 分析化学   实验教学   环保   综合素质  

摘要： 本文阐述了在新形势下的分析化学实验教学过程中,如何提高实验教学,提高学生的实验技能、提高学生个人的综合素质,为学生今后的学习和生活奠定基础,为社会培养合格人才所提出的观点。

关键词： 食品化学   天然药物   北京   国际认证   高级人才   药品进口   分析化学   传统药物  

摘要： 北京中奥芬食品与天然药物研究中心是我国第一家遵从GLP原则并完全符合其要求的民营实验室。中心拥有第一流的药物。食品和GLP研究方面的专家，拥有通晓国际认证．食品、药品进口等有关国际性事物的高级人才。有来自中国、德国、日本、芬兰的药物学、食品化学、分析化学、传统药物、新能源化学等研究领域的优秀科学家。

摘要： 为加强赛默飞国内客户的学术交流与合作,充分分享经验与科研成果,推动我国相关科研领域的发展,预计于2014年12月由《分析化学》杂志与赛默飞合作出版＂赛默飞双三元液相色谱应用专刊＂（以下简称为专刊）。

关键词： 无机及分析化学   教学改革   探讨  

摘要： 通过对独立学院无机及分析化学课程体系师资队伍现状、教学过程中存在的突出问题的深刻分析,提出目前教学中面临的主要问题,在实际教学过程中,通过优化教师结构,精炼教学内容,更新教学手段,生活实例导入新知识点联系专业实际,优化课程考核评价体系等,达到提高教学质量,提高学生科学素养和培养创新能力的目的。

关键词： 研究型学习   分析化学   创新能力  

摘要： 通过对分析化学教学现状的分析,提出了将"研究型学习"教学模式应用于药学分析化学教学的必要性、具体措施和方法,并对教学实践的效果进行了评价,提出了存在的问题和改进措施,旨在强化学生实践能力和创新能力的培养成效,提高分析化学的教学质量。

关键词： 离子液体   分析化学   应用  

摘要： 随着科学技术的发展,科技研究成果取得可喜成果,离子液体的应用研究也受到越来越多的关注。目前,离子液体在诸多领域得到了应用,其中最主要的是有机合成化学领域和应用化学领域。本文主要探讨离子液体在分析化学中的应用以及取得的研究进展。