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分析化学:历史

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核心提示:Much of early chemistry (1661-~1900AD) was analytical chemistry since the questions of what elements and chemicals were present in the world around us and what are their fundamental natures is very much in the realm of analytical chemistry. There wa


    Much of early chemistry (1661-~1900AD) was analytical chemistry since the questions of what elements and chemicals were present in the world around us and what are their fundamental natures is very much in the realm of analytical chemistry. There was also significant early progress in synthesis and theory which of course are not analytical chemistry. During this period significant analytical contributions to chemistry include the development of systematic elemental analysis by Justus von Liebig and systematized organic analysis based on the specific reactions of functional groups. The first instrumental analysis was flame emissive spectrometry developed by Robert Bunsen and Gustav Kirchhoff who discovered rubidium (Rb) and caesium (Cs) in 1860.[1]

    Most of the major developments in analytical chemistry take place after 1900. During this period instrumental analysis becomes progressively dominant in the field. In particular many of the basic spectroscopic and spectrometric techniques were discovered in the early 20th century and refined in the late 20th century.[2] The separation sciences follow a similar time line of development and also become increasingly transformed into high performance instruments.[3] In the 1970s many of these techniques began to be used together to achieve a complete characterization of samples. Starting in approximately the 1970s into the present day analytical chemistry has progressively become more inclusive of biological questions (bioanalytical chemistry), whereas it had previously been largely focused on inorganic or small organic molecules. Lasers have been increasingly used in chemistry as probes and even to start and influence a wide variety of reactions. The late 20th century also saw an expansion of the application of analytical chemistry from somewhat academic chemical questions to forensic, environmental, industrial and medical
questions, such as in histology.

    我们周围的世界都存在那些元素和化合物?它们的基本性质是什么?由于这些问题是分析化学领域内极为普遍的问题,所以早期化学(公元1661-~1900)的大部是分析化学。早期的综合分析及理论也有重大进步,当然这不是分析化学。这一时期分析化学对化学的贡献为:尤斯图斯-冯-李比希(Justus von Liebig)的系统元素分析、以官能团特殊反应为依据的系统化有机分析。首次仪器分析是火焰发射光谱法,是由罗伯特·本生(Robert Bunsen)和基尔霍夫(Gustav Kirchhoff)创造的,他们于1860年发现了元素铷 (Rb)和铯(Cs)。

    大多数重大进步发生在1900年以后。这一时期,仪器分析逐渐在该领域占主导地位。特别是许多基本分光光度技术和光谱技术在20世纪初期被人们发现,并在20世纪后期得以完善。分离科学沿着相似的时线发展,并逐步推出高性能仪器。20世纪70年代,人们将这类技术联合使用,使样品得以完整的鉴定。从70年代前后至今,分析化学逐渐将生物学(生物化学)问题囊括进来,因为此前生物化学着重研究无机分子或有机小分子。激光器越来越多地在化学中用作探测器,甚至用来推动并影响各种各样的反应。20世纪后期,分析化学的应用更加广泛,其应用上至专业化学问题,下达法医、环境、工业及医学问题,如,组织学。

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关键词: 分析化学 历史
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