The dissolution of carbon steel in 5% HCl in the temperature range of 30~90℃ was inhibited by two organic compounds having the general formula: ClR NH2(CH2)n NH2 RCl where R is a benzyl group. The behaviour of these ...The dissolution of carbon steel in 5% HCl in the temperature range of 30~90℃ was inhibited by two organic compounds having the general formula: ClR NH2(CH2)n NH2 RCl where R is a benzyl group. The behaviour of these inhibitors in acidic medium were investigated using weight loss method, open circuit potential and linear polarization technique. These inhibitors provided satisfactory corrosion inhibition for carbon steel in hydrochloric acid solutions even at higher temperature and acid concentration (10%). The electrochemical results showed that the polarization resistance (Rp) values increased with increasing inhibitor concentration, also the corrosion current decreased and a higher inhibition efficiency was obtained. The protective properties of these two organic inhibitors were attributed to the chemisorption mechanism展开更多
Crystalline carbon nitride(CCN)prepared by a molten-salt method is attracting increased attention because of its promising properties and excellent photocatalytic activity.In this work,we further improve the crystalli...Crystalline carbon nitride(CCN)prepared by a molten-salt method is attracting increased attention because of its promising properties and excellent photocatalytic activity.In this work,we further improve the crystallinity of CCN through synthesis by the molten-salt method under the action of aqueous hydrochloric acid(HCl)solution.Our results showed that the crystallinity of the as-prepared samples increased with increasing HCl concentration and reached the maximum value at 0.1 mol L^-1.This can be attributed to the removal of some potassium ions(K+)from the terminal amino groups of CCN by the aqueous HCl solution,which results in a release of the polymerization sites.As a result,the crystallinity of the as-prepared samples further increased.Moreover,the obtained 0.1 highly crystalline carbon nitride(0.1HCCN;treated with 0.1 mol L^-1 aqueous HCl solution)exhibited an excellent photocatalytic hydrogen evolution of 683.54μmol h^-1 g^-1 and a quantum efficiency of 6.6%at 420 nm with triethanolamine as the sacrificial agent.This photocatalytic hydrogen evolution was 2 and 10 times higher than those of CCN and bulk carbon nitride,respectively.The enhanced photocatalytic activity was attributed to the improved crystallinity and intercalation of K+into the xHCCN interlayer.The improved crystallinity can decrease the number of surface defects and hydrogen bonds in the as-prepared sample,thereby increasing the mobility of the photoinduced carriers and reducing the recombination sites of the electron-hole pairs.The K+intercalated into the xHCCN interlayer also promoted the transfer of the photoinduced electrons because these ions can increase the electronic delocalization and extend theπ-conjugated systems.This study may provide new insights into the further development of the molten-salt method.展开更多
Objective: In the acid-fast staining experiment of pathological tissues, sulfuric acid and hydrochloric acid were used to evaluate the staining results, so as to get the best staining method. Methods: Using sulfuric a...Objective: In the acid-fast staining experiment of pathological tissues, sulfuric acid and hydrochloric acid were used to evaluate the staining results, so as to get the best staining method. Methods: Using sulfuric acid differentiation solution and hydrochloric acid differentiation solution, the paraffin blocks of pathological tissues known to contain Mycobacterium tuberculosis were compared to evaluate the staining effect. Results: When 0.5% hydrochloric acid differentiation solution is used and the differentiation time is 6 s, the dyeing effect is better than that of sulfuric acid differentiation solution.展开更多
为更好地服务水利水电工程、岩土工程等行业土料勘察工作,建立了盐酸溶液浸提-离子色谱法测定中溶盐石膏(CaSO_(4)·2H_(2)O)含量的新方法。实验采用4.5m M Na_(2)CO_(3)/1.4m M Na HCO_(3)淋洗液,在1.0m L·min^(-1)流速下对...为更好地服务水利水电工程、岩土工程等行业土料勘察工作,建立了盐酸溶液浸提-离子色谱法测定中溶盐石膏(CaSO_(4)·2H_(2)O)含量的新方法。实验采用4.5m M Na_(2)CO_(3)/1.4m M Na HCO_(3)淋洗液,在1.0m L·min^(-1)流速下对硫酸盐进行测定,测定方法的相对标准偏差(RSD)为2.3%,加标回收率为91.0%~102%,检出限为0.003g·kg^(-1)。该方法操作简单、高效、准确度高,适用于工程勘察中大批量样品的测定。展开更多
文摘The dissolution of carbon steel in 5% HCl in the temperature range of 30~90℃ was inhibited by two organic compounds having the general formula: ClR NH2(CH2)n NH2 RCl where R is a benzyl group. The behaviour of these inhibitors in acidic medium were investigated using weight loss method, open circuit potential and linear polarization technique. These inhibitors provided satisfactory corrosion inhibition for carbon steel in hydrochloric acid solutions even at higher temperature and acid concentration (10%). The electrochemical results showed that the polarization resistance (Rp) values increased with increasing inhibitor concentration, also the corrosion current decreased and a higher inhibition efficiency was obtained. The protective properties of these two organic inhibitors were attributed to the chemisorption mechanism
基金supported by the National Natural Science Foundation of China(51672099,21403079)Sichuan Science and Technology Program(2019JDRC0027)Fundamental Research Funds for the Central Universities(2017-QR-25)~~
文摘Crystalline carbon nitride(CCN)prepared by a molten-salt method is attracting increased attention because of its promising properties and excellent photocatalytic activity.In this work,we further improve the crystallinity of CCN through synthesis by the molten-salt method under the action of aqueous hydrochloric acid(HCl)solution.Our results showed that the crystallinity of the as-prepared samples increased with increasing HCl concentration and reached the maximum value at 0.1 mol L^-1.This can be attributed to the removal of some potassium ions(K+)from the terminal amino groups of CCN by the aqueous HCl solution,which results in a release of the polymerization sites.As a result,the crystallinity of the as-prepared samples further increased.Moreover,the obtained 0.1 highly crystalline carbon nitride(0.1HCCN;treated with 0.1 mol L^-1 aqueous HCl solution)exhibited an excellent photocatalytic hydrogen evolution of 683.54μmol h^-1 g^-1 and a quantum efficiency of 6.6%at 420 nm with triethanolamine as the sacrificial agent.This photocatalytic hydrogen evolution was 2 and 10 times higher than those of CCN and bulk carbon nitride,respectively.The enhanced photocatalytic activity was attributed to the improved crystallinity and intercalation of K+into the xHCCN interlayer.The improved crystallinity can decrease the number of surface defects and hydrogen bonds in the as-prepared sample,thereby increasing the mobility of the photoinduced carriers and reducing the recombination sites of the electron-hole pairs.The K+intercalated into the xHCCN interlayer also promoted the transfer of the photoinduced electrons because these ions can increase the electronic delocalization and extend theπ-conjugated systems.This study may provide new insights into the further development of the molten-salt method.
文摘Objective: In the acid-fast staining experiment of pathological tissues, sulfuric acid and hydrochloric acid were used to evaluate the staining results, so as to get the best staining method. Methods: Using sulfuric acid differentiation solution and hydrochloric acid differentiation solution, the paraffin blocks of pathological tissues known to contain Mycobacterium tuberculosis were compared to evaluate the staining effect. Results: When 0.5% hydrochloric acid differentiation solution is used and the differentiation time is 6 s, the dyeing effect is better than that of sulfuric acid differentiation solution.
文摘为更好地服务水利水电工程、岩土工程等行业土料勘察工作,建立了盐酸溶液浸提-离子色谱法测定中溶盐石膏(CaSO_(4)·2H_(2)O)含量的新方法。实验采用4.5m M Na_(2)CO_(3)/1.4m M Na HCO_(3)淋洗液,在1.0m L·min^(-1)流速下对硫酸盐进行测定,测定方法的相对标准偏差(RSD)为2.3%,加标回收率为91.0%~102%,检出限为0.003g·kg^(-1)。该方法操作简单、高效、准确度高,适用于工程勘察中大批量样品的测定。
