共查询到19条相似文献,搜索用时 187 毫秒
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探究性实验能大大提升学生对自然科学的兴趣爱好,但合适的探究素材并不多见。介绍了美国《化学教育》杂志连载20年的以福尔摩斯与华生的侦破故事为主题的系列报道,在文中破案过程被设计为探究性实验,使相对枯燥的化学实验变得生动有趣。经小范围使用该素材对中高年级学生展开开放实验,收效良好。 相似文献
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一、引言量子化学在化学各领域中的应用日趋广泛,使得非专门从事理论化学工作的化学工作者理解和应用量子化学的一般原理和结果变得更加重要了。1977年D.K.Hoffman等人提出了一种简单、易懂、直观而又行之有效的分子轨道理论的图示方法——生成轨道Generator Orbital)法这种方法对于不熟悉群论的化学工作者了解分子中(尤其是多原子分子中)分子 相似文献
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遗传算法在计算机辅助药物分子设计中的应用 总被引:6,自引:1,他引:5
作为一种重要的启发式优化算法,遗传算法在计算机辅助药物分子设计中得到了广泛的应用.本文介绍了遗传算法的基本概念以及工作原理,同时结合作者科研组的工作,就遗传算法在定量构效关系、构象分析、药效团模拟、分子对接以及虚拟组合化学等方面的应用做了系统的阐述。 相似文献
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在硼酸盐化学、盐湖材料化学及成盐元素化学研究中,由于红外及相关联用技术的应用而取得了很大进展。此文对近年来我国在盐湖化学研究工作中应用红外及相关联用技术的工作进行了综述,对红外新技术在盐湖化学中的应用前景进行了展望。共引用文献65篇。 相似文献
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建立了一种适用于分析冰毒杂质的方法,并分析其形成原因。将冰毒样品溶于1 mL 0.1 mol/L pH7.0的磷酸盐缓冲液(4份缓冲液1份10%Na2CO3),杂质用0.5 mL乙酸乙酯萃取。结果共有8种物质被检出。N-甲酰甲基安非他明、N-乙酰甲基安非他明在样品中出现,说明此批冰毒由苯丙酮(phenyl-2-propanone,P-2-P)经Leuckart法合成。N-乙基甲基安非他明的检出,则说明用于合成此批冰毒的P-2-P由苯甲醛和硝基乙烷合成。从实验结果看,该法可以满足冰毒杂质分析的需要,为分析冰毒杂质成分的成因、判断冰毒样品的合成路径提供重要信息。 相似文献
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Forensic examination results play an increasingly important role in bringing many criminal investigations to a successful
conclusion. The quality of the results of examinations performed in forensic science laboratories has always been the concern
of the individual forensic scientist. The interpretations and results are presented in court to non-experts. Therefore, it
is essential to ensure and maintain the highest standards of achievements and accuracy in forensic science. Many factors are
important contributors to quality assurance in forensic science. Some unique subjects affect not only the mode of inquiry
but also the way in which information is presented to the court, i.e. exhibits collection and sample handling, investigation,
examination techniques, report writing and court testimony. 相似文献
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射击残留物作为涉枪案件的重要物证,是法庭科学领域的重要研究对象.射击残留物主要源于未燃烧或者部分燃烧的发射药、底火等,主要残留于射击者、枪支及被射客体上.随着各类分析检验方法的发展,针对射击残留物中的有机成分和无机成分,射击残留物的检验方法也从简单的化学检验发展到更加准确的仪器分析. 相似文献
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《Chemie in Unserer Zeit》2017,51(6):384-391
Forensics deals with the scientific methods to gather information at a crime scene for solving criminal actions. DNA forensics uses genetic material for these purposes. DNA fingerprinting is established as an important method for police detective work since the end of the 1980s. Currently, DNA forensics faces completely new possibilities through the application of more efficient high‐throughput sequencing methods, summarized as Next Generation Sequencing (NGS). Using NGS it could be possible to predict numerous externally visible characteristics including the complete facial shape of an unknown perpetrator. This article aims at presenting practices of forensic DNA analyses used to date and extending the picture for future possibilities and challenges. 相似文献
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Upon utilization of some common methods described in the literature for the synthesis of chiral, 2-substituted 2,5-diketopiperazines, extensive racemization was observed. Further investigation showed that heating in the presence of a mild base racemized the chiral center in the product diketopiperazines. A generalized, readily scalable route was sought and, after investigating the effect of base and temperature, conditions were identified that promoted cyclization without erosion of enantiomeric excess. An array of functionalization was tolerated and this procedure serves as a useful and reliable method for the facile synthesis of this important class of compounds. 相似文献