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• 2016-07-29 04:42發(fā)布了問(wèn)答

  離心機(jī)分為哪幾種？能定制嗎？廣州園大機(jī)械提供定制服務(wù)嗎？

  　

  476人看過(guò)

• 2016-01-27 08:11發(fā)布了問(wèn)答

  鮮竹瀝微波提取設(shè)備商

  　

  551人看過(guò)

• 2015-01-14 18:49發(fā)布了問(wèn)答

  離心機(jī)出現(xiàn)e97 error lid lock是什么問(wèn)題

  　

  874人看過(guò)

• 2012-05-02 19:48發(fā)布了問(wèn)答

  我想知道這尿酸高的危害 ??！懂的說(shuō)說(shuō)吧

  　

  284人看過(guò)

• 2011-04-24 08:56發(fā)布了問(wèn)答

  離心機(jī)的主動(dòng)軸，要采用哪種軸承？

  　

  505人看過(guò)

• 2009-07-20 09:49發(fā)布了問(wèn)答

  ZY空調(diào)（離心機(jī)組）電壓是選擇高壓好還是低壓好？

  ZY空調(diào)（離心機(jī)組）電壓是選擇高壓好還是低壓好？ 請(qǐng)從經(jīng)濟(jì)型和技術(shù)性進(jìn)行比較分析，請(qǐng)盡量詳細(xì)。答得好的獎(jiǎng)分我還追加.

  288人看過(guò)

• 2009-05-18 11:22發(fā)布了問(wèn)答

  環(huán)境英語(yǔ)文獻(xiàn)翻譯 急用

  Thereisagrowinginterestindeterminingmercury(Hg)levelsinthemarineenvironmentaswellasinfishforhumanconsumption.Methylmercury(MeHg)inparticularisthemosttoxicandbioaccumulati... There is a growing interest in determining mercury(Hg) levels in the marine environment as well as in fish for human consumption. Methyl mercury(Me Hg)in particular is the most toxic and bioaccumulative form of mercury in food webs and it is the predominant chemical form making up 80%-90% of the total mercury present in fish muscle tissue.Hence，fish and other organisms at the end of the food chain constitute the major source of MeHg in the human . As outcome of this risk，MeHg has been classically monitored in fish， and methodologies for mercury speciaion have increased significantly since the early 1990s. Currently， microwave-assisted extraction (MAE) has provided an efficient alternative strategy to conventional techniques for solvent extraction of a large amount of organometals compounds.The analytical techniques most frequently applied for Hg speciation analysis involve GC(GasChromatography) ， GC-CICP-MS(Gas Chromatography -CInductively Coupled Plasma Mass Spectrometry) supercritical fluids chromatography (SFC)，ion chromatograph(IC)， HPLC-CCVAAS(High Performance Liqui Chromatography-Cold Vapor Atomic Absorption Spectrometry) or ICP-MS systems .Several authors recommended a back-extraction of mercury species from organic solvents to cysteine or sodium thiosulphate aqueous solutions .Because MeHg is the most common organomercury compound in biological materials ，here we offer a new simple and cost-effective method to determine MeHg. Basically， this method combines the microwave assisted extraction followed by clean-up with cysteine acetate solution and MeHg quantification by a direct mercury analyzer (DMA). 展開(kāi)

  392人看過(guò)