? asked in 科學化學 · 1 decade ago

關於重金屬實驗翻譯..謝謝

When applying the two means t-test (Miller & Miller, 1993) and comparing the t statistics with the critical value for 95% confidence and 6_ of freedom that is 2.447, it was found that the mean results for Cu leaching from the two methods were significantly different.

This indicated that organic matters (protein amino acids) had important role in controlling the release of Cu.

H2O2 could dissociate to hydroxyl radical (OH_) that could attack proteins, carbohydrates and polyunsaturated fatty acids present in the samples.

Hence, it improved the efficiency of the Cu extraction (Azouzi et al., 1998; Goodman, Green, & McPhail, 1984).

On the other hand, H2O2 was an insignificant variable for Cd and Zn leaching from both fish and mussel samples.

Regarding to above discussion, the concentrations of the used acids did not affect the leaching efficiency.

A mild and appropriate condition of leaching solution should be 1:1:1 HNO3(0.5 M):HCl(0.5 M):H2O2(0.5 M).

This acid mixture was used for the extraction of the metals from real sample.

The results showed that the ratio (%) was not satisfied.

From literature review, many authors strongly recommended the moderate concentration of both acids whose the values were ranging from 1 to 3 M in final solution (Azouzi et al., 1998; Bermejo-Barrera, Mun˜iz-Naveiro et al., 2000; Bermejo-Barrera et al., 2001; Bermejo-Barrera, Muniz-Naveiro et al., 2001).

Successful leaching of Cu and Zn was achieved, but the Cd was partially leached.

The higher concentration was used, the better efficiency was found (Bermejo-Barrera, Mun˜iz-Naveiro et al., 2000).

Thus, a formula of leaching solution as 1:1:1 HNO3(4 M):HCl(4 M):H2O2(0.5 M) was chosen for further experiments.

In this study samples were treated with 6 mL of de-ionized water and the results were compared with the ones from leaching by 6 mL of 1:1:1 HNO3(4 M):HCl(4 M):H2O2(0.5 M) solution.

The overall found ratios were less than 15%.

Update:

不會不會.真得很謝謝你.其實我碰重金屬實驗才半年...真ㄉ很感謝你

但是我不了解消化(我們是用高濃度硝酸去溶解上機).但我不明白抄因波萃取(還有用這樣的消化法嗎?).因為重金屬實驗好像相關資料不多耶.不知道怎模查.何況火焰aas用得是ppm.石墨aas是用ppb...有點難度

1 Answer

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  • 1 decade ago
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    你這實在是太長了,我盡力翻了。(點數難賺阿~)

    當應用此兩個 t測試方法(Miller & Miller, 1993) 時,以臨界值是95%的信任度和6 自由度做比較 t 統計是2.447。發現從兩種方法濾出的銅與平均結果相當不同。

    這表明有機物(蛋白質氨基酸) 在控制銅的釋放過程中有重要的角色。

    H2O2會解離出氫氧基根自由基,那會攻擊蛋白質、存在於樣品的碳水化合物和聚合非飽和脂肪酸。

    因此,這改進銅的萃取效率(Azouzi 等 1998; Goodman, Green, & McPhail, 1984).

    另一方面,H2O2對鎘和鋅的從魚和貝蚌樣品漏出是個無意義的變量。

    關於以上的討論,被使用的酸的濃度沒影響漏出的效率。

    一種溫和、合適之條件的過濾溶液應該是1︰1︰1的HNO3(0.5 M) :HCl(0.5 M) :H2O2(0.5 M) 。

    這種酸混合物用於抽出來自真正樣品的金屬。

    結果顯示出比率(%)不夠滿意。

    從文獻回顧中, 很多作者強烈建議最後溶液中,使用範圍在1到3M,含有兩種酸的溫和濃度。 (Azouzi et al., 1998; Bermejo-Barrera, Mun˜iz-Naveiro et al., 2000; Bermejo-Barrera et al., 2001; Bermejo-Barrera, Muniz-Naveiro et al., 2001).

    取得成功濾出的銅和鋅,但是Cd只有部分濾出。

    使用較高濃度,發現較好的效率。(Bermejo-Barrera, Mun˜iz-Naveiro et al., 2000).

    因此,為更進一步的實驗選擇的過濾溶液公式是1︰1︰1的HNO3(4 M) :HCl(4 M) :H2O2(0.5 M) 。

    在這項研究內樣品中,是用去6 mL的離子水處理,結果是比較以6 mL的1︰1︰1的HNO3(4 M) :HCl(4 M) :H2O2(0.5 M) 漏出的溶液。

    總共發現的比率少於15%。

    2008-02-10 11:14:37 補充:

    因為沒前後文,第一句我比較沒把握。

    sorry~

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