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北京石油化工學(xué)院2026年研究生招生接收調(diào)劑公告

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幻雪之戀

銅蟲 (初入文壇)

應(yīng)助: 0 (幼兒園)
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注冊: 2012-10-23
專業(yè): 無機(jī)材料化學(xué)

[求助] 急求翻譯為中文，化學(xué)式可以不管

The inhibiting power of anti-corrosive pigments depends upon a number of parameters, namely the pigment solubility,the pH, the properties of the substrate and the composition of the solution. The levels of inhibitor concentration achieved in the extracts were much lower for the phosphate than for the chromate, although in both cases the inhibiting effect has proved to be sufficient to provide high inhibition efficiency to zinc in 0.1 M NaCl. In both cases, inhibition was the result of the formation of a layer of inhibitor on the surface. In the chromate , the film was formed instantly after immersion. In-hibition by the phosphate was a slower process, as confirmed by the SVET and the OCP measurements. The chromate was also the more efficient inhibitor. On the bare metal, it led to the highest charge transfer resistance and also to the devel-opment of a protective layer characterized by a capacitance decrease of approximately two orders of magnitude, when compared with the reference solution.

When these pigments are used in a coating, leaching to the solution is the first step towards inhibition. Since this is a slow process, inhibition can only be detected after a sufficient concentration of inhibitor is achieved near the metal. The mechanisms of passivation by zinc chromate are usually described by an oxidizing action of CrO42−. In the process of film formation, Cr(VI) is reduced to Cr(III), while Zn is oxidized to Zn(OH)2, according to the reaction scheme
3Zn + 2CrO42 −+ 5H2 O →3Zn(OH)2 + Cr2 O3 + 4OH−
Chromate is usually considered to act especially at the dam-aged areas of the coating, where the electropositive metals are left exposed to the aggressive medium, and are therefore available for providing free electrons for chromate reduction. For the conditions of our experiments and for the duration of the tests, we found none of the pigments had the power to inhibit the corrosion occurring at the defect.

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1樓 2014-05-09 18:05:25

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shiranjiang

金蟲 (正式寫手)

翻譯EPI: 14
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幻雪之戀: 金幣+50, 翻譯EPI+1, ★有幫助 2014-05-11 13:58:17

防銹顏料的抑制能力取決于許多參數(shù),即色素的溶解性、pH值、基質(zhì)的性質(zhì)和溶液的成分。雖然在磷酸鹽中提取得到的抑制劑的濃度等級比在鉻酸鹽中低得多，但在這兩種情況下，其抑制效果已足夠?yàn)?.1 M氯化鈉溶液中的鋅提供高的抑制效率。在這兩種情況下，抑制作用是在表面形成一層抑制劑的結(jié)果。在鉻酸鹽中，浸入后立即形成薄膜。SVET和OCP的測量結(jié)果證實(shí)了在磷酸鹽中的抑制作用是一個(gè)緩慢的過程，鉻酸鹽也是一種更有效的抑制劑。在裸露的金屬上，與參考溶液相比，它導(dǎo)致了最高電荷轉(zhuǎn)移電阻，也導(dǎo)致了以一個(gè)電容減少約兩個(gè)數(shù)量級為特點(diǎn)的保護(hù)層的發(fā)展。當(dāng)在涂料中使用這些顏料時(shí)，抑制的第一步是從溶液中浸出，因?yàn)檫@是一個(gè)緩慢的過程，只有金屬附近抑制劑的濃度足夠時(shí)，才能檢測到抑制作用。通常用CrO42−的氧化作用來描述鋅鉻酸鹽的鈍化機(jī)制，根據(jù)化學(xué)反應(yīng)方程，在膜的形成過程中，Cr(VI) 還原成Cr(III)，而Zn被氧化，生成Zn(OH)2。
3Zn + 2CrO42 −+ 5H2 O →3Zn(OH)2 + Cr2 O3 + 4OH−

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2樓2014-05-10 13:31:27