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排序方式: 共有1336条查询结果,搜索用时 15 毫秒
1.
《International Journal of Hydrogen Energy》2022,47(69):29685-29697
Electrocatalytic water splitting is an important method to produce green and renewable hydrogen (H2). One of the hindrances for wide applications of electrocatalysis in H2 production is the lack of freshwater resources. Comparatively, seawater splitting has become an effective approach for large-scale H2 production due to its abundant reserves. However, the increased complexity of seawater content emerged more problems in electrocatalytic seawater splitting. Recently, various strategies have been reported on improving the performance of electrocatalysts applied in seawater. Herein, this review firstly analyzed the mechanisms and challenges of electrocatalytic seawater splitting to evolve H2, and summarized the recent progress on H2 production in electrocatalytic seawater splitting. Furthermore, suggestions for future work have been provided for guidance. 相似文献
2.
《International Journal of Hydrogen Energy》2022,47(11):6975-6985
A technology for cyclic generation of hydrogen and oxygen using electrodes made of variable valency material that does not need the use of separating ion-exchange membranes is presented. The technological solution enables to fabricate electrolyzers for uninterrupted producing high-pressure hydrogen with reduced energy intensity of the production. The total work for compressing 1 m3 of hydrogen and 0.5 m3 of oxygen has been estimated. Results of investigation of influence of discrete supply of DC current to the electrolysis cell, in order to improve the processes of gas evolution and to simplify the power systems of the electrolysis plant, have been considered. There is also considered an electrolysis installation equipped with a thermosorption compressor in which LaNi5 is used as a hydride-forming compound. The comparative characteristics of the developed electrolyzer and the currently used hydrogen generators are given. 相似文献
3.
《International Journal of Hydrogen Energy》2022,47(49):21033-21043
Magnetron sputtered low-loading iridium-ruthenium thin films are investigated as catalysts for the Oxygen Evolution Reaction at the anode of the Proton Exchange Membrane Water Electrolyzer. Electrochemical performance of 50 nm thin catalysts (Ir pure, Ir–Ru 1:1, Ir–Ru 1:3, Ru pure) is tested in a Rotating Disk Electrode. Corresponding Tafel slopes are measured before and after the CV-based procedure to compare the activity and stability of prepared compounds. Calculated activities prior to the procedure confirm higher activity of ruthenium-containing catalysts (Ru pure > Ir–Ru 1:3 > Ir–Ru 1:1 > Ir pure). However, after the procedure a higher activity and less degradation of Ir–Ru 1:3 is observed, compared to Ir–Ru 1:1, i.e. the sample with a higher amount of unstable ruthenium performs better. This contradicts the expected behavior of the catalyst. The comprehensive chemical and structural analysis unravels that the stability of Ir–Ru 1:3 sample is connected to RuO2 chemical state and hcp structure. Obtained results are confirmed by measuring current densities in a single cell. 相似文献
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阐述了180kA大型铝电解槽槽壳的位移现场测试手段、槽壳表面位移特征和槽壳所受内力的计算方法,并对槽壳结构优化设计做了分析 相似文献
7.
牛初乳中提取乳铁蛋白工艺的研究 总被引:4,自引:0,他引:4
从牛初乳中分离提取乳铁蛋白,建立快速分离纯化乳铁蛋白的工艺.选择弱酸性阳离子交换剂CM SEPHAROSE FAST FLOW装柱,脱脂牛初乳在4 ℃下进行动态吸附上柱后进行阶跃洗脱.通过对洗脱条件的比较优化,确定了分离提取乳铁蛋白的最佳工艺条件为:牛初乳料液pH 6.6,上柱速度300 mL/h,阶跃洗脱剂的体积分数分别为1.5%和5.0%的NaCl,洗脱体积流速200 mL/h.乳铁蛋白洗脱液经过超滤和冷冻干燥,得到冻干粉纯度可达98.98%,得率为29.0%. 相似文献
8.
对HG/T 2471-1993《隔膜法电解槽金属阳极涂层》和HG 2951-1988(原GB 9844-88)《隔膜法金属阳极电解槽制造技术条件》标准的修订版HG/T 2471-2001《电解槽金属阳极涂层》和HG/T 2951-2001《隔膜法金属阳极电解槽》进行了技术性解释。公布了按照HG/T 2471-2001《电解槽金属阳极涂层》要求对产品质量达标企业的型式检验结果。 相似文献
9.
通过对离子膜电解槽停车泄料时发生的闪爆事故的分析,找出引起闪爆事故的主要原因是由漏入的氯气和氢气在A槽阳极室内达到爆炸极限后遇到尖端的放电造成的电火花所致。同时分析了A槽槽电压升高的原因,介绍了预防事故发生的措施。 相似文献