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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(52):22165-22179
Aluminum alloy bipolar plates have unique application potential in proton exchange membrane fuel cell (PEMFC) due to the characteristics of lightweight and low cost. However, extreme susceptibility to corrosion in PEMFC operation condition limits the application. To promote the corrosion resistance of aluminum alloy bipolar plates, a Ni–P/TiNO coating was prepared by electroless plating and closed field unbalanced magnetron sputter ion plating (CFUMSIP) technology on the 6061 Al substrate. The research results show that Ni–P interlayer improves the deposition effect of TiNO outer layer and increase the content of TiN and TiOxNy phases. Compared to Ni–P and TiNO single-layer coatings, the Ni–P/TiNO coating samples exhibited the lowest current density value of (1.10 ± 0.02) × 10?6 A·cm?2 in simulated PEMFC cathode environment. Additionally, potential cyclic polarization measurements were carried out aiming to evaluate the durability of the aluminum alloy bipolar plate during the PEMFC start-up/shut-up process. The results illustrate that the Ni–P/TiNO coating samples exhibit excellent stability and corrosion resistance. 相似文献
4.
《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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6.
气动贯通式潜孔锤反循环连续取心取样钻进新技术在河南钼矿中应用 总被引:4,自引:0,他引:4
三道庄钼矿勘探生产中钻遇的地层非常复杂,采用其他方法均无法实现钻进,经过分析比较,决定采用贯通式潜孔锤反循环连续取心(样)钻进新技术来解决该地层钻进难、成孔难、取样难等三大问题。文章从钻进技术特点、工作原理等方面对该技术进行详细分析,得出其具有钻进效率高、岩心(样)采取率高、成孔质量好等突出优点。并介绍了钻进主要设备机具的配套、施工工序、操作要点、遇到问题的解决方法等。在河南钼矿露天采石场应用该项技术,有效避免了塌孔和卡钻事故,工程进展顺利、质量好、岩心(样)采取率在98%以上,取得了良好的效果。针对在生产试验中遇到的某些问题,作者提出了一些改进建议。 相似文献
7.
A method of measuring and identifying the static parameters of a bipolar transistor is considered. The characteristic of the transistor, from which the parameters of the model are determined, is chosen depending on what group the calculated parameters belong to. The characteristics are measured in such a way that the equations of the model describing them can be reduced to the simplest form. 相似文献
8.
适用于微机的核蒸汽发生器热工水力分析程序—SGTH—2 总被引:1,自引:0,他引:1
本程序用于计算核蒸汽发生器的热工水力分布参数以及一次侧流动压降、二次侧自然循环和稳态特性,将本程序的计算结果与法国对同型号蒸汽发生器的实测数据以及用 ATHOS 程序的相应计算结果进行比较,表明主要热工水力参数能令人满意地吻合。 相似文献
9.
壳牌煤气化工艺在荷兰德姆科列克IGCC工厂的应用 总被引:3,自引:0,他引:3
介绍采用壳牌煤气化工艺的荷兰德姆科列克250MW整体煤气化烧气--蒸汽联合循环发电厂的建厂过程及运行经验。阐述了IGCC能量平衡原理、SCGP系统流程和运行操作指标,对壳牌煤气化装置的优良性能和发展前景进行了总结和展望。 相似文献
10.
钻井液用BDY-1便携式堵漏仪 总被引:3,自引:2,他引:1
在堵漏过程中,对堵漏材料和堵漏浆配方的优选是决定堵漏成功的关键。为了能在现场对堵漏进行评价,研制出BDY-1便携式堵漏仪,该堵漏仪主要由不锈钢钢柱圈钢,压力表等加工而成,该堵漏仪体积小,重量轻,价格低,仅为国产堵漏仪的1/20。试验结果表明BDY-1便携式堵漏仪操作简便,可快速对堵漏材料进行评价并筛选出堵漏配方;数据重复性好,准确可靠,能达到进口或国产堵漏仪的水平;在模拟漏层选定后,可采用多套压力梯度,对堵漏浆封堵效果进行评价,在压力梯度选定后,可评价堵漏浆对不同类型漏层的封堵效果;如果扩大压力范围,可对封堵后的漏层进行破裂试验,从而确定合理的钻井施工参数;适用现场操作和应用。 相似文献