在线观看亚洲精品专区-在线观看亚洲免费-在线观看亚洲免费视频-在线观看亚洲欧美-欧美freexxx-欧美free嫩交video

食品伙伴網(wǎng)服務(wù)號
 
 
當(dāng)前位置: 首頁 » 專業(yè)英語 » 專業(yè)知識 » 正文

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.

    我們周圍的世界都存在那些元素和化合物?它們的基本性質(zhì)是什么?由于這些問題是分析化學(xué)領(lǐng)域內(nèi)極為普遍的問題,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步,當(dāng)然這不是分析化學(xué)。這一時期分析化學(xué)對化學(xué)的貢獻為:尤斯圖斯-馮-李比希(Justus von Liebig)的系統(tǒng)元素分析、以官能團特殊反應(yīng)為依據(jù)的系統(tǒng)化有機分析。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)重大進步發(fā)生在1900年以后。這一時期,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)沿著相似的時線發(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))問題囊括進來,因為此前生物化學(xué)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(xué)中用作探測器,甚至用來推動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)用上至專業(yè)化學(xué)問題,下達法醫(yī)、環(huán)境、工業(yè)及醫(yī)學(xué)問題,如,組織學(xué)。

更多翻譯詳細(xì)信息請點擊:http://www.trans1.cn
 
關(guān)鍵詞: 分析化學(xué) 歷史
[ 網(wǎng)刊訂閱 ]  [ 專業(yè)英語搜索 ]  [ ]  [ 告訴好友 ]  [ 打印本文 ]  [ 關(guān)閉窗口 ] [ 返回頂部 ]
分享:

 

 
推薦圖文
推薦專業(yè)英語
點擊排行
 
 
Processed in 0.068 second(s), 14 queries, Memory 0.89 M
主站蜘蛛池模板: 成人一级毛片| 特级一级毛片| 最新版天堂资源中文官网| 怡红院日本| 婷婷久久综合网| 日韩黄色免费| 美女被羞羞产奶视频网站| 精品亚洲欧美无人区乱码| 国产一级特黄aa级特黄裸毛片| 国产激烈床戏无遮挡在线观看| 69pao强力打造免费高速| 天天插天天狠天天透| 久久精品久久久久| 激情伦成人综合小说| 久热99| 天天操电影| 欧美一区福利| 国产色婷婷精品免费视频| 亚洲夜夜骑| 久久91精品牛牛| 欧美人与zoxxxx视频| 男女交黄| 熊出没之环球大冒险旧版免费观看| 色人人| 激情91| 午夜国产视频| 久久婷婷午色综合夜啪| 国产精品嫩草影院一二三区入口| 香蕉视频在线观看国产| 哪里可以看免费毛片| 59日本人xxxxxxxxx69| 在线亚洲成人| 日本www.色| 4hu44四虎在线观看| 九九热精品国产| 亚洲欧美日韩特级毛片| 亚洲色图欧美视频| 玖玖色视频| 失禁h啪肉尿出来高h| 国产亚洲精品aa在线看| 色wwwwww|