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AMT在碳钢-5%HCl体系中的缓蚀行为及其机理研究 总被引:1,自引:0,他引:1
用极化曲线、失重和EIS等方法研究了AMT(2-氨基-5-巯基-1,3,4-噻二唑)在碳钢/5%HCl体系中的缓蚀行为和机理.研究表明AMT在该体系中表现为混合型缓蚀剂,其缓蚀机理可归因于几何覆盖效应,在电极表面的吸附符合Langmuir吸附等温式,吸附热约为27.10kJ/mol左右,其EIS图谱在自腐蚀电位下与空白一样,只有一个时间常数,但一定程度阴极极化时出现低频吸附容抗 相似文献
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小麦面筋蛋白盐酸脱酰胺工艺优化及其酶解敏感性 总被引:2,自引:0,他引:2
文以小麦面筋蛋白为原料,优化了盐酸对小麦面筋蛋白的脱酰胺工艺,比较了最佳脱酰胺工艺下的小麦面筋蛋白在胰酶、风味蛋白酶和碱性蛋白酶酶解过程中蛋白回收率和水解度的变化,并对其酶解36 h酶解液的自由基吸收能力(ORAC)抗氧化特性进行分析评价。研究结果表明,盐酸脱酰胺的工艺条件是:小麦面筋蛋白浓度为24%,0.30 mol/L的HCl,65℃,24 h脱酰胺;在该工艺条件下,胰酶酶解液蛋白回收率和水解度最高,酶解效果最好;高脱酰胺程度小麦面筋蛋白在胰酶酶解36h后酶解液的蛋白回收率和水解度高于低脱酰胺程度的酶解液;ORAC抗氧化特性分析表明高脱酰胺程度小麦面筋蛋白酶解液的ORAC值高于低脱酰胺程度的酶解液,其ORAC值最高为(689.67±10.22)μmol Trolox/g。 相似文献
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SO2 and HCl are major pollutants emitted from waste incineration processes. Both pollutants are difficult to remove completely and can enter the catalytic reactor. In this work, the effects of SO2 and HCl on the performance of Rh/Al2O3 and Rh-Na/Al2O3 catalysts for NO removal were investigated in simulated waste incineration conditions. The characterizations of the catalysts were analyzed by BET, SEM/EDS, XRD, and ESCA. Experimental results indicated the 1%Rh/Al2O3 catalyst was significantly deactivated for NO and CO conversions when SO2 and HCl coexisted in the flue gas. The addition of between 2 and 10 wt.% Na promoted the activity of the 1%Rh/Al2O3 catalyst for NO removal, but decreased the CO oxidation and BET surface area. The catalytic activity for NO removal was inhibited by HCl as a result of the formation of RhCl3. Adding Na to the Rh/Al2O3 catalyst decreased the inhibition of SO2 because of the formation of Na2SO4, which was observed in the XRD and ESCA analyses. SEM mapping/EDS showed that more S was residual on the surface of the Rh-Na/Al2O3 catalyst than Cl. 相似文献
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目的通过三乙烯四胺和苯甲酸合成IMBT,再利用IMBT、H3PO3和甲醛经过曼尼希反应制得IMBTM,并探究其对碳钢在HCl水溶液中的缓蚀作用。方法采用动态失重法、电化学技术以及热力学等方法研究缓蚀剂IMBT和IMBTM在60℃、1 mol/L的盐酸溶液中对10#碳钢的缓蚀性能和吸附规律。结果利用IR对产物进行表征,均得到了产物特征峰。在动态失重试验中,IMBT和IMBTM两种缓蚀剂的质量浓度为3 g/L时,碳钢的腐蚀速率分别为3.92、2.94 g/(m2·h),缓蚀剂的缓蚀率分别为79.65%和84.75%。极化曲线试验表明随着两种缓蚀剂浓度增加,腐蚀电位正移,阳极电流密度下降明显。交流阻抗的测试显示随着两种缓蚀剂浓度增大,容抗弧半径逐渐增大,且在相同浓度下,添加IMBTM时的容抗弧半径更大。另外,随着缓蚀剂浓度的增加,拟合参数Rct增大、Cdl减小,证明缓蚀剂在金属表面取代了水,并吸附成膜。研究等温吸附模型,发现数据带入Langmuir等温吸附方程后,表现出了很好的线性关系。结论在1 mol/L HCl溶液中,IMBT和IMBTM对10#碳钢均有缓蚀作用,且IMBTM的缓蚀作用较高。两种缓蚀剂均属于阳极型缓蚀剂,对阳极的缓蚀作用较高。且两种化合物在10#碳钢表面上的吸附过程为自发放热过程,其吸附规律遵循Langmuir等温吸附式,属于单分子层吸附。 相似文献
18.
Liquid phase hydrodechlorination of chlorophenols over Pd/C and Pd/Al2O3: a consideration of HCl/catalyst interactions and solution pH effects 总被引:1,自引:0,他引:1
The liquid phase hydrodechlorination (HDC) of 2-chlorophenol (2-CP) and 2,4-dichlorophenol (2,4-DCP) has been studied over 1% (w/w) Pd/C and Pd/Al2O3 under conditions of minimal mass transport constraints. The HDC of 2,4-DCP generated HCl and 2-CP as the only intermediate partially dechlorinated product which reacts further to yield phenol; cyclohexanone was formed over Pd/Al2O3, but not over Pd/C, prior to complete dechlorination. Pd/Al2O3 is characterized (on the basis of TEM analysis) by a narrow distribution of smaller Pd particles to give a surface area weighted mean particle DIAMETER = 2.4 nm that is appreciably lower than the value of 13.2 nm established for Pd/C, where the latter is characterized by a broader distribution of larger (spherical) particles. The addition of NaOH served to increase fractional dechlorination by suppressing HDC inhibition due to the HCl that is generated. Reuse of the catalysts revealed an appreciable deactivation of Pd/C and a limited loss of activity in the case of Pd/Al2O3. Deactivation of Pd/C can be linked to a decrease (up to ca. 60%) in the initial BET surface area allied to appreciable leaching (up to ca. 40%) of the starting Pd content through the corrosive action of HCl and, while the average Pd diameter is essentially unaffected, there is evidence of a preferred leaching of larger Pd particles. The stronger metal/support interactions prevalent in Pd/Al2O3 results in limited Pd leaching and comparable initial HDC activities during catalyst reuse with/without NaOH addition. Inclusion of HCl in the reaction mixture (pH 5–1.5) resulted in a marked decline in the initial HDC rate associated with Pd/Al2O3 and a lesser drop in HDC activity for Pd/C. The difference in response to bulk solution pH variations are discussed in terms of the nature of the reactive species in solution and the amphoteric behavior of the Pd supports. 相似文献
19.
Kaoru Abe Yasuhiro Sakurai Akira Okuyama Kazuhiro Sasaki Kei Tawarada 《Journal of the science of food and agriculture》2009,89(6):1097-1100
BACKGROUND: The behavior of cadmium in ecosystems needs to be monitored because of the human toxicity of this heavy metal. The need recently arose for a simple and quick on‐site test for trace levels of Cd in food and environmental samples. In response, an immunochromatographic assay kit for detecting Cd was manufactured by Kansai Electric Power Co. of Japan. This kit uses the antigen–antibody complex reaction between the Cd–EDTA complex and an anti‐Cd–EDTA antibody and shows the results in terms of the degree of color developed on a test paper. We previously reported the successful use of this kit to determine Cd concentrations in brown rice. Here, we applied the kit to the determination of Cd concentrations in rice foliage and soil. RESULTS: Cadmium in rice foliage was not extracted successfully by the method used for brown rice. However, it was successfully extracted by 0.1 mol L?1 HCl solution at a rice foliage:HCl ratio of 1:20, and coexisting metals were removed sufficiently by the column treatment. The Cd concentrations determined by immunochromatographic assay were well correlated with the values obtained by acid decomposition and inductively coupled plasma mass spectrometry. The 0.1 mol L?1 HCl‐extractable Cd concentration in soil was also determined successfully with the kit. CONCLUSION: Approximate Cd concentrations in rice plants and 0.1 mol L?1 HCl‐extractable Cd concentrations in soil can be monitored easily and quickly by this method at locations where facilities for acid digestion and precision analysis are not available. Copyright © 2009 Society of Chemical Industry 相似文献
20.
Reports an error in "Alpha-adrenergic receptors in hypothalamus for the suppression of feeding behavior by satiety" by D. L. Margules (Journal of Comparative & Physiological Psychology, 1970[Oct], Vol 73[1], 1-12; see record 1971-03588-001). On page 3, paragraph 1 of the Method section, the angle of implantation of cannulas was 6° from the perpendicular; in paragraph 2 of the Method section, the following sentence was omitted: All rats were maintained on a reversed dark-light cycle (lights off at 0800 hr. and on at 2000 hr. EST) and were drugged in the dark. On page 10, paragraph 6, line 10 of the Discussion section, "abolishes" should read "enhances." In "Precocious mating in male rats following treatment with androgen or estrogen" by Michael J. Baum (Journal of Comparative & Physiological Psychology, 1972[Mar], Vol. 78[3], 356-367; see record 1972-22393-001), on page 367 the date of receipt should read August 24, 1970. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献