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分析化學:歷史

放大字體  縮小字體 發布日期:2009-02-03
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.

    我們周圍的世界都存在那些元素和化合物?它們的基本性質是什么?由于這些問題是分析化學領域內極為普遍的問題,所以早期化學(公元1661-~1900)的大部是分析化學。早期的綜合分析及理論也有重大進步,當然這不是分析化學。這一時期分析化學對化學的貢獻為:尤斯圖斯-馮-李比希(Justus von Liebig)的系統元素分析、以官能團特殊反應為依據的系統化有機分析。首次儀器分析是火焰發射光譜法,是由羅伯特·本生(Robert Bunsen)和基爾霍夫(Gustav Kirchhoff)創造的,他們于1860年發現了元素銣 (Rb)和銫(Cs)。

    大多數重大進步發生在1900年以后。這一時期,儀器分析逐漸在該領域占主導地位。特別是許多基本分光光度技術和光譜技術在20世紀初期被人們發現,并在20世紀后期得以完善。分離科學沿著相似的時線發展,并逐步推出高性能儀器。20世紀70年代,人們將這類技術聯合使用,使樣品得以完整的鑒定。從70年代前后至今,分析化學逐漸將生物學(生物化學)問題囊括進來,因為此前生物化學著重研究無機分子或有機小分子。激光器越來越多地在化學中用作探測器,甚至用來推動并影響各種各樣的反應。20世紀后期,分析化學的應用更加廣泛,其應用上至專業化學問題,下達法醫、環境、工業及醫學問題,如,組織學。

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