who are u asked in 科學化學 · 1 decade ago

無機化學...20點...拜託幫忙翻譯>”<..

題目:

An Immobilized Ortho-Palladated Dimethylbenzylamine Complex as an

Efficient Catalyst for the Methanolysis of Phosphorothionate Pesticides

簡介:

The methanolysis of a series of P=S phosphorothionate pesticides (fenitrothion, coumaphos, diazinon, and

dichlofenthion) catalyzed by an ortho-palladated complex covalently attached to two different solid supports,

macroporous polystyrene and amorphous silica gel, was studied. Both the polystyrene and the silica-based catalysts

showed excellent activity in methanol near neutral pH (neutral s

spH ) 8.38) at ambient temperature. These

heterogeneous catalysts can be readily recovered and reused without significant loss of activity. Fifty milligrams of

the silica-supported catalyst SiPd1 offered an acceleration of up to 8.6 × 109-fold for the methanolysis of fenitrothion

(2) over the methoxide-promoted background reaction at s

spH ) 8.8. For the same reaction, 50 mg of polystyrenesupported

complex PSPd2 provided a 3.7 × 109-fold acceleration at s

spH ) 8.8. When accounting for the amount

of palladium in the solid, the slight superiority of silica over polystyrene as a solid support is believed to be a result

of several possible factors including a higher concentration of active sites accessible to the reaction solvent and

a more hydrophilic surface environment that allows better interaction of the methanol solvent with the attached

palladacycle. Unlike the behavior in homogeneous solution, the rate of methanolysis of the substrates catalyzed by

the solid catalysts was relatively insensitive to the nature of the substrate, probably indicating that a mass transport

process is rate limiting. The solid-supported materials effectively decompose malathion at roughly stoichiometric

ratios, but they are strongly inhibited by the thiol product resulting from the cleavage of the P=S(SR) linkage.

3 Answers

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  • 下雪
    Lv 7
    1 decade ago
    Favorite Answer

    (1)在這問,頂多也是幫您貼上翻譯器然後再貼回來,您為什麼不去試試翻譯器呢?

    (2)應該不是整篇都看不懂吧?

    2009-07-08 22:44:48 補充:

    這是此摘要的網路資料http://pubs.acs.org/doi/abs/10.1021/ic801382e%EF%B... Pesticides的Methanolysis反應(內文應該有一些比較,看此complex是否真的有提升催化效率)。

    簡介部份:

    文獻探討過利用ortho-palladated complex,鍵結附著在多孔性聚苯乙烯、amorphous silica gel等載體(還是要翻做基材?),作為催化一系列P=S phosphorothionate pesticides(例如fenitrothion, coumaphos, diazinon, and dichlofenthion)的methanolysis反應。

    兩種催化劑(polystyrene and the silica-based)在pH~=8.38、接近中性、室溫的甲醇環境下有極佳的反應活性。

    此非勻相催化劑可以迅速復原、再使用而不會喪失其特定(指methanolysis的催化)活性。

    50mg的silica-supported catalyst SiPd1(這個建議您看清楚是如何定義的,譬如誰接誰等等)讓fenitrothion的methanolysis速度上升8.6 109倍(fold是倍數的意思)

    接下來這段就類似(2) over the methoxide-promoted background reaction at s spH ) 8.8. For the same reaction, 50 mg of polystyrene supported complex PSPd2 provided a 3.7 109-fold acceleration at sspH ) 8.8.

    接下來是我比較看不懂的ㄧ段

    When accounting for the amount of palladium in the solid, the slight superiority(優點、優勢) of silica over polystyrene as a solid support is believed to be a result of several possible factors including(包含多個可能的因素) a higher concentration of active sites accessible to the reaction solvent(較多的可接受反應溶劑的活化位置) and a more hydrophilic surface environment that allows better interaction of the methanol solvent with the attached palladacycle.(以及較親水的表面環境讓methanol與attached palladacycle的反應更好)。

    不同於勻相溶液中的作用,固體催化劑催化基質的methanolysis速率相對純基質較不靈敏,推測是mass transport process is rate limiting。

    The solid-supported materials effectively decompose malathion at roughly stoichiometric ratios(solid-supported materials 在粗略化學計量比對malathion有效decompose)

    but they are strongly inhibited by the thiol product resulting from the cleavage of the P=S(SR) linkage.

    最後那裡應該是說斷了什麼鍵、然後一些影響的,翻的有點爛,就之前粗淺的認識稍作翻譯,希望對您有幫助。

    至於您說要跟我討論這我可能幫不上大忙,之後走物化組,跟您所接觸的東西差蠻遠的,不好意思。

    2009-07-08 22:45:24 補充:

    關於Methanolysis

    http://www.rsc.org/Publishing/Journals/cc/News/B61...

  • 1 decade ago

    http://tw.knowledge.yahoo.com/question/question?qi...

    感覺像是相同的問題

    這兩位同學被分派到相同的作業嗎??

  • 1 decade ago

    恩...我用過YAHOO跟GOOGLE的翻譯器...可是還是看不太懂...

    希望有人用翻譯器能稍微白話一點...我第一次發問...也不太懂規則...

    希望各位大大見諒>"<..

    2009-07-07 09:23:15 補充:

    喔喔喔...我重複貼了...

    第一次問問題..我以為題目不見了結果還在...

    又怕刪了...會看不到...

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