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茶葉及其提取液中重金屬cu、pb的檢測——畢業(yè)論文-wenkub

2022-09-06 08:44:43 本頁面
 

【正文】 受害尤為嚴(yán)重。據(jù)調(diào)查,現(xiàn)在很多兒童體內(nèi)平均含鉛量普遍高于年輕人 。但是若是茶葉中含有了過量的鉛銅,在人們飲茶的同時(shí)隨之?dāng)z入人體,將會(huì)對(duì)人們的身體造成巨大的影響。在 化學(xué)工業(yè)中 廣泛應(yīng)用于制造真空器、 蒸餾 鍋、釀造鍋等??捎糜谥圃煦U彈。用于制造合金。方鉛礦( PbS)直到今天都是人們提取鉛的主要來源。鉛被用作建筑材料,用在乙酸鉛電池中,用作槍彈和炮彈,焊錫、獎(jiǎng)杯和一些合金中也含鉛。er. are determined in this thesis. Tea samples are pretreated with acid digestion method and boiled water immersion and extraction method. The optimal pretreatment conditions are selected and the results between mentioned two methods are pared. Our experiments indicates that the concentrations of Cu and Pb from selected tea samples are all below the maximum values of national tea standards and thus safety to be used. Moreover, results from acid digestion are better than those from boiled water extraction. Keywords Flame atomic absorption spectrometry, Tea, Acid degistion , boiled water immersion 蘇州科技學(xué)院本科生畢業(yè)論文 III 目 錄 1 緒論 ......................................................................................................................... 1 鉛、銅的測定 意義 ................................................................................................ 1 鉛、銅的簡介 ..................................................................................................... 1 鉛、銅對(duì)人體的影響 ......................................................................................... 2 研究背景 ................................................................................................................ 4 相關(guān)標(biāo)準(zhǔn) ............................................................................................................. 4 各種測定方法 ..................................................................................................... 4 研究目的 ................................................................................................................ 5 2 實(shí)驗(yàn)部分 ................................................................................................................. 6 儀器和試劑 ............................................................................................................ 6 儀器 ..................................................................................................................... 6 試 劑 ..................................................................................................................... 6 實(shí)驗(yàn)內(nèi)容和方法 .................................................................................................... 6 樣品 ..................................................................................................................... 6 標(biāo)準(zhǔn)曲線 ............................................................................................................. 7 實(shí)驗(yàn)方法 ............................................................................................................. 7 加標(biāo)回收率 [8] ...................................................................................................... 8 3 結(jié)果與討論 ............................................................................................................. 9 實(shí)驗(yàn)結(jié)果 ................................................................................................................ 9 最佳實(shí)驗(yàn)條件確定 ............................................................................................. 9 標(biāo)準(zhǔn)曲線 ........................................................................................................... 11 樣品測定結(jié)果 ...................................................................................................... 11 酸法消解 ........................................................................................................... 11 沸水溶出法 ....................................................................................................... 12 加標(biāo)回收率 .......................................................................................................... 13 酸法消解測銅的加標(biāo)回收率 ........................................................................... 13 酸法消解測鉛的加標(biāo)回收率 ........................................................................... 13 沸水溶出法測定銅的加標(biāo)回收率 ................................................................... 14 蘇州科技學(xué)院本科生畢業(yè)論文 IV 沸水溶出法測定鉛的加標(biāo)回收率 ................................................................... 14 方法優(yōu)越性比較 .................................................................................................. 15 兩種方法測銅優(yōu)越性比較 ............................................................................... 15 兩種方法測鉛優(yōu)越性比較 ............................................................................... 15 兩種方法相關(guān)性 .................................................................................................. 16 兩種方法測銅的相關(guān)性 ................................................................................... 16 兩種方法測鉛的相關(guān)性 ................................................................................... 16 結(jié) 論 ......................................................................................................................... 17 致 謝 ......................................................................................................................... 18 參 考 文 獻(xiàn) ............................................................................................................... 19 附錄 A 原始數(shù)據(jù) ..................................................................................................... 20 附錄 B 譯文及外文原文 .......................................................................................... 24 蘇州科技學(xué)院本科生畢業(yè)論文 1 1 緒論 鉛、銅的測定
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