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1.
利用慢应变速率技术(SSRT),并结合电化学极化曲线和阻抗实验方法研究了苯并三氮唑(BTA)添加剂对1Cr18Ni9Ti奥氏体不锈钢在0.5mol·L-1HCl+0.5mol·L-1NaCl溶液中应力腐蚀和均匀腐蚀的缓蚀作用.结果表明,这种添加剂的缓蚀作用主要是抑制腐蚀的阳极过程而产生的.  相似文献   

2.
腐蚀金属电极的电化学频域测量研究进展──金属腐蚀与防护研究所电化学研究介绍之一曹楚南(金属腐蚀与防护国家重点实验室,金属腐蚀与防护研究所,沈阳110015)腐蚀电化学是研究与腐蚀有关的电化学问题,具体的研究对象为腐蚀金属电极。虽然电化学中的基本原理和...  相似文献   

3.
铁腐蚀;硫化氢;H2S对丙炔醇在Fe/H2SO4体系中缓蚀作用的影响  相似文献   

4.
黄铜脱锌的抑制   总被引:4,自引:0,他引:4  
汪的华  邹津耘 《应用化学》1997,14(5):104-106
黄铜脱锌的抑制汪的华邹津耘*邱万川杨兴和(武汉大学环境科学系武汉430072)关键词黄铜脱锌,抑制作用,砷,缓蚀剂1996-12-08收稿,1997-06-20修回金属腐蚀与防护国家重点实验室和国家自然科学基金资助课题抑制黄铜脱锌目前受到普遍重视.抑...  相似文献   

5.
聚酰亚胺模型化合物的结构模拟   总被引:1,自引:0,他引:1  
朱英  史桂珍 《应用化学》1998,15(3):97-99
聚酰亚胺模型化合物的结构模拟朱英史桂珍陆天虹*(中国科学院长春应用化学研究所长春130022)关键词聚酰亚胺,模型化合物,结构模拟,LB膜,半经验分子轨道计算方法1997-09-30收稿,1998-01-07修回金属腐蚀和防腐国家实验室资助项目近年来...  相似文献   

6.
锌在硫酸溶液中腐蚀速度及其缓蚀作用的研究   总被引:1,自引:0,他引:1  
锌在硫酸溶液中腐蚀速度及其缓蚀作用的研究杨春芬,沈报春(云南大学化学系,昆明650O91)金属的腐蚀及其缓蚀作用的研究具有重要的实际意义。近年来,有关锌腐蚀动力学及寻找高效缓蚀剂的研究有一些报道 ̄[1-3],但多在中性介质及用电化学方法研究,本文是在...  相似文献   

7.
本文简要阐明了为什么金属的腐蚀主要以电化学腐蚀的形式出现,剖析了腐蚀过程电化学动力学参数的物理意义,以及金属腐蚀的防护原理、常用的腐蚀防护方法乃至腐蚀过程的一些特殊应用。  相似文献   

8.
缓蚀剂和缓蚀涂层能够在金属表面形成一层致密保护膜,从而达到延缓金属腐蚀的目的。其具有成本低、可操作性强、缓蚀效果好、寿命长等优点,成为海洋工程防腐中一类重要的材料。围绕海洋工程中钻井平台、风力发电机、航空母舰和核潜艇等中易发生腐蚀的部位介绍化学缓蚀剂及缓蚀涂层的结构、性质,并突出其重要作用。  相似文献   

9.
电化学STM技术在金属腐蚀科学中的应用及研究进展   总被引:4,自引:0,他引:4  
本文介绍了电化学STM在金属腐蚀电化学研究领域的技术优势.其最大特点是可以在金属腐蚀环境中和原子/分子水平上,实时、原位、三维空间观察,并可以通过电位控制表面电极过程.综述了电化学STM在钝化膜结构、缓蚀剂的自组装膜、金属表面原子的活性溶解等揭示腐蚀缓蚀机理的研究领域中所起的重要作用以及最新研究进展.  相似文献   

10.
丙炔醇聚合股对铁在酸性溶液中的缓蚀作用   总被引:1,自引:0,他引:1  
应用电化学交流阻抗谱技术研究了Fe/H_2SO_4与Fe/H_2SO_4+H_2S体系中丙炔醇(PA)聚合膜的形成及其缓蚀作用,同时利用SEM、AFM及EDX对PA聚合不同时期铁表面腐蚀形貌进行观测与成分分析.结果表明,Fe/H_2SO_4与 Fe/H_2SO_4+ H_2S体系中 PA可逐渐聚合成膜,从而有效抑制基体的腐蚀,使电极表面较为平整,微米尺度下呈现规则的块状结构;但Fe/H_2SO_4体系中宏观上PA并未形成连续的保护膜,导致电极表面局部发生腐蚀;而Fe/H_2SO_4+H_2S体系中,H_2S、HS-在电极表面的吸附减缓了PA聚合成膜,但长时间腐蚀后,由于硫化物的生成覆盖在PA聚合膜上,使其具有长期缓蚀效能.  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

13.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。  相似文献   

16.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

17.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

18.
袁丽秋 《化学教育》2006,27(5):8-10
面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。  相似文献   

19.
20.
黄酮化合物的合成研究进展   总被引:2,自引:0,他引:2  
黄酮化合物是一类具有多种生物活性的天然产物,其经典的合成方法主要为查耳酮路线和β-丙二酮路线.近年来出现了许多新技术、新方法.本文介绍了2'-羟基查尔酮的氧化关环法、黄烷酮氧化法、改进的Baker-Venkataraman法及其他合成黄酮化合物的方法.  相似文献   

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