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分析化學(xué):歷史

放大字體  縮小字體 發(fā)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?chē)氖澜缍即嬖谀切┰睾突衔?它們的基本性質(zhì)是什么?由于這些問(wèn)題是分析化學(xué)領(lǐng)域內(nèi)極為普遍的問(wèn)題,所以早期化學(xué)(公元1661-~1900)的大部是分析化學(xué)。早期的綜合分析及理論也有重大進(jìn)步,當(dāng)然這不是分析化學(xué)。這一時(shí)期分析化學(xué)對(duì)化學(xué)的貢獻(xiàn)為:尤斯圖斯-馮-李比希(Justus von Liebig)的系統(tǒng)元素分析、以官能團(tuán)特殊反應(yīng)為依據(jù)的系統(tǒng)化有機(jī)分析。首次儀器分析是火焰發(fā)射光譜法,是由羅伯特·本生(Robert Bunsen)和基爾霍夫(Gustav Kirchhoff)創(chuàng)造的,他們于1860年發(fā)現(xiàn)了元素銣 (Rb)和銫(Cs)。

    大多數(shù)重大進(jìn)步發(fā)生在1900年以后。這一時(shí)期,儀器分析逐漸在該領(lǐng)域占主導(dǎo)地位。特別是許多基本分光光度技術(shù)和光譜技術(shù)在20世紀(jì)初期被人們發(fā)現(xiàn),并在20世紀(jì)后期得以完善。分離科學(xué)沿著相似的時(shí)線(xiàn)發(fā)展,并逐步推出高性能儀器。20世紀(jì)70年代,人們將這類(lèi)技術(shù)聯(lián)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(xué)逐漸將生物學(xué)(生物化學(xué))問(wèn)題囊括進(jìn)來(lái),因?yàn)榇饲吧锘瘜W(xué)著重研究無(wú)機(jī)分子或有機(jī)小分子。激光器越來(lái)越多地在化學(xué)中用作探測(cè)器,甚至用來(lái)推動(dòng)并影響各種各樣的反應(yīng)。20世紀(jì)后期,分析化學(xué)的應(yīng)用更加廣泛,其應(yīng)用上至專(zhuān)業(yè)化學(xué)問(wèn)題,下達(dá)法醫(yī)、環(huán)境、工業(yè)及醫(yī)學(xué)問(wèn)題,如,組織學(xué)。

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關(guān)鍵詞: 分析化學(xué) 歷史
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