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Nannan Chen Yanhong Wang Xiaoqiang Du Xiaoshuang Zhang 《International Journal of Hydrogen Energy》2021,46(49):25114-25120
Urea electrolysis is a promising technology for hydrogen production, which can alleviate environmental pollution of urea-rich wastewater. It's worth noting that electrochemistry activity can be significantly improved by reasonably regulating the electron configuration around the active site for the doped materials. In this work, a series of well-tuned Ni doped CoWO4 nanoarrays on Ni foam supports have been prepared through a typical hydrothermal approach for the first time. Moreover, the resulting Ni–CoWO4-2 material significantly promotes urea oxidation performance with an applied potential of 1.35 V at 50 mA cm?2, which is lower than that of water oxidation reaction (1.60 V). Density functional theory results suggest that the Ni doped CoWO4 has larger urea adsorption energy compared with CoWO4 and the CO(NH2)2 molecule is strongly adsorbed on surface of Ni doped CoWO4, which is beneficial to accelerate the kinetics of the reaction and improve the electrocatalytic activity of the urea electrolysis. 相似文献
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采用微动摩擦磨损试验机在干摩擦条件下对新型高速重载传动轴用25CrNi2MoV钢进行微动磨损试验,研究了不同载荷(50~200N)和频率(15~30Hz)下该钢的微动磨损性能。结果表明:在频率为20Hz条件下,当载荷由50N增至200N时,25CrNi2MoV钢的平均摩擦因数由0.766减至0.661,磨损体积由19.65×10^-3 mm^3增至75.83×10^-3 mm^3;在载荷为30N条件下,当频率由15Hz增至30Hz时,平均摩擦因数由0.790增至0.905,磨损体积由11.43×10^-3 mm^3增至23.88×10^-3 mm^3;在不同试验参数下,25CrNi2MoV钢磨损表面均出现了氧化和犁沟现象,磨损机制包含氧化磨损和磨粒磨损;在频率为20Hz条件下,载荷为50,100N时,25CrNi2MoV钢的磨损机制以黏着磨损为主,载荷为150,200N时,主要磨损机制为疲劳磨损;在载荷为30N条件下,频率为15~25Hz时,磨损机制以磨粒磨损为主,当频率增至30Hz时,磨损机制以疲劳磨损为主。 相似文献
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Yi Fang Jie Teng Xiaoqiang Ding 《Hemodialysis international. International Symposium on Home Hemodialysis》2015,19(1):2-10
China has a large population and bears a heavy burden of kidney diseases. Acute kidney injury (AKI) is increasingly prevalent in China and is associated with severe morbidity and mortality. The inadequacies of early diagnosis and management remain the major challenges to Chinese nephrologists. There is an urgent need for a nationwide, or even a global effort to increase an awareness of the devastating effects of AKI, to develop professional preventive strategies, as well as to achieve early diagnosis and early intervention. In this article, we review the increasing incidence of AKI and complexity behind prevention and management, focusing on differences in various clinical settings in China. 相似文献
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以山一村农居SOHO为例,总结了文化创意产业村改造建设措施,从村民社会保障、政府政策探索、企业招商管理策略等角度,分析了文化创意产业村建设过程中的问题,并从社会学的视角提出了相应的解决策略,为城中村改造探索了新的可行模式。 相似文献
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渗透汽化膜分离技术适合应用于有机溶剂中水的脱除、废水处理与溶剂回收等。。文中根据渗透汽化膜分离的技术特点,对其在石油化工领域的应用进行了分析,该技术能够降低生产过程中的能耗,设备投资费用少,且经济环保。 相似文献
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Xiaoqiang Zou Kakeza Nadege Irabogora Ninette Ye Wen Shibin Wu Xuan Jiang Hui Zhang Qingzhe Jin Xingguo Wang 《Journal of the American Oil Chemists' Society》2020,97(3):263-270
Docosahexaenoic acid (DHA)-rich diacylglycerol (DAG)-rich oil was prepared by lipase-catalyzed glycerolysis of microbial oil from Schizochytrium sp. in a solvent-free system. The reaction parameters including lipase type, substrate molar ratio, temperature, lipase concentration, and reaction time were screened. The selected conditions were determined as follows: Novozym® 435 (Novozymes A/S, Bagsvaerd, Denmark) as biocatalyst at 8 wt%, substrate ratio (DHA-rich microbial TAG/glycerol) of 1:1 mol/mol, temperature of 50 °C, and reaction time of 12 hours. Under these conditions, the triacylglycerol (TAG), DAG, and monoacylglycerol (MAG) contents in the product were 36.4%, 48.2%, and 15.4%, respectively. The lipase was reused successively for 18 cycles without significant loss of activity under the conditions given above. Fatty acid composition analysis of the final product showed that the contents of DHA in TAG, DAG, and MAG were 53.9%, 44.9%, and 34.8%, respectively. DHA-rich DAG has the potential to be used as an ingredient in infant formula to increase the bioavailability of DHA. 相似文献