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991.
Xu Yunfei He Liang Lei Qi Luo Hongzhi Zhou Cheng Mao Wei Cheng Xiaojuan Li Jianmin Zou Guifu 《SILICON》2021,13(5):1641-1646
Silicon - Nowadays, casted multicrystalline silicon is the most important material in photovoltaic industry. In order to reduce the cost of silicon ingots, the recycle of silicon ingot tailings is... 相似文献
992.
Faraz Montazersadgh Hao Zhang Anas Alkayal Benjamin Buckley Ben W.Kolosz Bing Xu Jin Xuan 《Frontiers of Chemical Science and Engineering》2021,15(1):208-219
Utilizing CO2 in an electro-chemical process and synthesizing value-added chemicals are amongst the few viable and scalable pathways in carbon capture and utilization technologies.CO2 electro-reduction is also counted as one of the main options entailing less fossil fuel consumption and as a future electrical energy storage strategy.The current study aims at developing a new electrochemical platform to produce low-carbon e-biofuel through multifunctional electrosynthesis and integrated co-valorisation of biomass feedstocks with captured CO2.In this approach,CO2 is reduced at the cathode to produce drop-in fuels(e.g.,methanol)while value-added chemicals(e.g.,selective oxidation of alcohols,aldehydes,carboxylic acids and amines/amides)are produced at the anode.In this work,a numerical model of a continuous-flow design considering various anodic and cathodic reactions was built to determine the most techno-economically feasible configurations from the aspects of energy efficiency,environment impact and economical values.The reactor design was then optimized via parametric analysis. 相似文献
993.
Zhihong Xu Tao Jiang Hao Zhang Yujun Zhao Xinbin Ma Shengping Wang 《Frontiers of Chemical Science and Engineering》2021,15(3):698
Novel MgO-doped CaO sorbent pellets were prepared by gel-casting and wet impregnation. The effect of Na+ and MgO on the structure and CO2 adsorption performance of CaO sorbent pellets was elucidated. MgO-doped CaO sorbent pellets with the diameter range of 0.5-1.5 mm exhibited an excellent capacity for CO2 adsorption and adsorption rate due to the homogeneous dispersion of MgO in the sorbent pellets and its effects on the physical structure of sorbents. The results show that MgO can effectively inhibit the sintering of CaO and retain the adsorption capacity of sorbents during multiple adsorption-desorption cycles. The presence of mesopores and macropores resulted in appreciable change of volume from CaO (16.7 cm3∙mol−1) to CaCO3 (36.9 cm3∙mol−1) over repeated operation cycles. Ca2Mg1 sorbent pellets exhibited favorable CO2 capture capacity (9.49 mmol∙g−1), average adsorption rate (0.32 mmol∙g−1∙min−1) and conversion rate of CaO (74.83%) after 30 cycles. 相似文献
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IE5为国际电工委员会(IEC)于2016年发布的目前全球最高的电动机能效等级。针对IE5能效等级目标开展了三相异步电动机研制。在设计方面,主要考虑采用优质的冷轧硅钢片,尝试不同风扇结构型式和不等匝绕组型式,并针对小功率电机考虑采用铸铜转子工艺方案,降低了电机损耗。在工艺方面,主要考虑提高加工精度,减小定、转子冲片毛刺等,进一步降低电机的空载损耗。样机测试结果表明,效率、功率因数、起动电流、起动转矩、最大转矩、温升等指标均达到设计要求,实现了IE5能效等级三相异步电动机研制目标。 相似文献
1000.
Computational Fluid Dynamics (CFD) simulation is one of the important methods to study the performance and in-fluencing factors of turbine flow sensors. According to the working characteristics of the turbine flow sensor, the passive simulation method based on the six degrees of freedom (6-DOF) model and dynamic mesh is proposed in this paper. The reliability of the simulation method is verified by steady-state experiments and unsteady-state experiments. The results show that the trend of meter factor with flow rate acquired from the simulation is close to the experimental results, and the deviation between the simulation result and the experiment result is low with a maximum deviation of 2.88%. In the unsteady simulation study, the impeller speed changes with the inlet velocity of the turbine flow sensor, which has a good follow-up. The passive simulation method can be used to predict the dynamic performance of the turbine flow sensor. 相似文献