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981.
982.
《International Journal of Hydrogen Energy》2021,46(76):37977-37985
The poor kinetics is the main issue hindering MgH2 for practical hydrogen storage application. In this work, the tricarboxybenzene was used to construct the stable Ni MOF (Ni-BTC300) as the catalyst for MgH2. The prepared MOFs maintained their chemical structure after 300 °C calcining and doped to MgH2 by ball milling. The dispersed, uniformly bonded Ni atoms can improve the kinetics of the composites, which could desorb 5.14 wt% H2 within 3 min at 300 °C. And the stable MOF structure leading to good cycle stability in both kinetics and capacity, with retention of 98.2% after 10 cycles. 相似文献
983.
Mahin Baladi Movlud Valian Maryam Ghiyasiyan-Arani Masoud Salavati-Niasari 《International Journal of Hydrogen Energy》2021,46(40):21026-21039
Hydrogen storage technology is one of the most challenging issues due to the increasing demand for fossil fuel replacement and the reduction of greenhouse gas emissions. In the current paper, the main aim is one-step and eco-friendly preparation of DyFeO3-ZnO nanocomposites using Barberry fruit extract as natural precursor (with the role of both fuel and capping agent) to compare with various conventional carboxylic acids. To further examine, the effect of different parameters like calcination temperature and the type of the chelating agent was scrutinized to acquire optimum shape, structure, morphology and size of the obtained products. This is the first effort on the investigation of the hydrogen storage capacity of DyFeO3-ZnO nanocomposites in terms of role of morphology. The electrochemical hydrogen storage capacity of obtained DyFeO3-ZnO nanocomposites was studied mediated by chronopotentiometry charge-discharge methods in KOH medium. The synthesis of nanocomposites in the presence of chemical or natural capping agent (carboxylic acids or Barberry fruit extract) led to different morphologies which affects to the electrochemical performance. As a result, the electrode which is provided by plate-like DyFeO3-ZnO nanocomposites performed 600.11 mAh/g discharge capacity compared with other samples. Based on the obtained results, DyFeO3-ZnO nanocomposites can be promising compounds to improve the electrochemical performance of hydrogen storage. 相似文献
984.
地下盐穴储气库盐岩热损伤机理 总被引:2,自引:2,他引:0
基于变质量热力学原理,建立盐穴储气库注采过程中的工程热力学分析数学模型,给出了单个注气和采气过程中温度和压力随时间变化的解析解,作为数值模拟的边界条件。根据金坛储气库的基本数据和盐岩实验研究参数,利用COMSOL Multiphysics有限元软件建立单腔盐穴注采过程的温度-应力耦合模型,模拟恒定注采速率下盐腔围岩的拉伸损伤、剪切损伤和膨胀损伤分布情况,研究夹层和热应力对围岩损伤的影响。基于热应力理论,结合模拟结果分析盐穴储气库注、采气过程中围岩的热损伤机理。模拟结果表明:在热应力存在的情况下,夹层的存在促进了围岩损伤的产生,无夹层时围岩无损伤发生,有夹层时围岩存在损伤;注气过程和采气过程的损伤发生位置存在差别:注气过程损伤多发生在夹层附近的盐岩中,采气过程损伤多发生在夹层中;膨胀损伤的范围最广,且损伤范围覆盖了前2种损伤,因此实际生产过程中推荐使用膨胀损伤判据,损伤评价结果更为保守。 相似文献
985.
M. Yu. Zadorozhnyy S. N. Klyamkin D. V. Strugova L. K. Olifirov G. S. Milovzorov S. D. Kaloshkin V. Yu. Zadorozhnyy 《国际能源研究杂志》2016,40(2):273-279
Ball milling technique was used for deposition of the polytetrafluoroethylene (PTFE) coating on the powder of TiFe intermetallic compound. Measurement of pressure–composition hydrogen absorption isotherms revealed that the polymer‐coated TiFe intermetallic compound kept its hydrogen storage ability. The TiFe/PTFE material demonstrated resistance to surface poisoning even after a prolonged exposure to air and was not subjected to pulverization during multiple hydrogenation–dehydrogenation cycles. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
986.
Huali Hu Wenbiao Shen Pengxia Li 《International Journal of Food Science & Technology》2014,49(2):399-409
Here we investigated the effect of hydrogen sulphide (H2S) on postharvest quality of mulberry fruit and possible underlying mechanisms. Endogenous H2S content first increased after harvest and then decreased sharply with the process of ripening and senescence. A fumigation with H2S released from 0.8 mm NaHS solution could significantly enhance the endogenous H2S content by increasing the activities of D‐cysteine desulfhydrase and L‐cysteine desulfhydrase. NaHS could significantly slow down the ripening rate of mulberry fruit and reduce the respiratory intensity and anthocyanin content. Moreover, H2S fumigation was able to obviously delay or slow down the decreases in soluble protein, titratable acidity and ascorbate contents. Further results showed that activities of representative antioxidant enzymes in H2S‐treated sample were higher than those of control samples during storage, resulting in a decrease in superoxide anion production. Together, these results clearly indicate that H2S fumigation has a potential role in the preservation of mulberries. 相似文献
987.
先阐述了服务器虚拟化技术的特点和优势,分析了华三的虚拟化产品特点,再论述了服务器虚拟化技术如何应用于校园数字化建设,以期达到降低运行成本、提升使用效率的目的。 相似文献
988.
分析了盐酸脱吸工序中稀盐酸储槽抽裂事故产生的原因;通过稀盐酸储槽的压力式液位计DCS历史曲线记录来间接分析稀盐酸储槽内压力变化情况,剖析负压的形成过程。结果表明:脱吸塔产生较大的负压是因为系统急停、温度下降后在略低于盐酸溶液恒沸点时发生冷凝相变而引起的。 相似文献
989.
990.
《Fusion Engineering and Design》2014,89(9-10):2001-2007
This paper summarises the present status of the ITER tritiated waste management strategy under development in France. This paper describes the specific challenges posed by this radioactive waste containing tritium as well as the solutions planned for the various waste categories and the implementation expected for the ITER tritiated waste, including the features of the future interim storage facility called INTERMED. Several options to reduce temporary storage duration as well as to minimise out-gassing rates and tritium discharges into the environment are under study, the related issues and the preliminary results obtained are shown. The first lessons learned for fusion development and their extrapolation to future reactors are outlined based on four parameters: materials, operating temperature, fuel cycle efficiency and tritium removal technologies. 相似文献