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71.
OR Spectrum - This paper studies a multi-period investment–consumption optimization problem with a stochastic discount rate and a time-varying utility function, which are governed by a... 相似文献
72.
Kuikui Wang Guanglei Wu Haijie Cao Hongliang Li Xiusong Zhao 《International Journal of Hydrogen Energy》2018,43(15):7440-7446
In this study, we used a combination of graphene oxide-based porous carbon (GC) and titanium chloride (TiCl3) to improve the reversible dehydrogenation properties of magnesium hydride (MgH2). Examining the effects of GC and TiCl3 on the hydrogen storage properties of MgH2, the study found GC was a useful additive as confinement medium for promoting the reversible dehydrogenation of MgH2. And TiCl3 was an efficient catalytic dopant. A series of controlled experiments were carried out to optimize the sample preparation method and the addition amount of GC and TiCl3. In comparison with the neat MgH2 system, the MgH2/GC-TiCl3 composite prepared under optimized conditions exhibited enhanced dehydrogenation kinetics and lower dehydrogenation temperature. A combination of phase/microstructure/chemical state analyses has been conducted to gain insight into the promoting effects of GC and TiCl3 on the reversible dehydrogenation of MgH2. Our study found that GC was a useful scaffold material for tailoring the nanophase structure of MgH2. And TiCl3 played an efficient catalytic effect. Therefore, the remarkably improved dehydrogenation properties of MgH2 should be attributed to the synergetic effects of nanoconfinement and catalysis. 相似文献
73.
Against a background of deepened globalization, the socio-spatial distribution characteristics of the employed population are one of the important perspectives that reflect the impact of globalization on urban social space. Based on data of the population census of Shanghai in 2000 and 2010, using location quotient and index of dissimilarity, this paper analyzes the residential differentiation evolution in Shanghai from 2000 to 2010. The results show that except the high-end service industry, the residential differentiation of the employees in the other three types of industries has intensified but is not serious. In addition, the proportion of employees in high-end service industry within the Middle Ring has increased, while that of employees in the middle-and low-end service industry beyond the Middle Ring has increased, which further proves that globalization has an increasingly obvious impact on the socio-spatial differentiation in Shanghai. However, the adjustment in spatial development made by the Shanghai municipal government in response to globalization makes the socio-spatial evolution of Shanghai greatly different from the suburbanization of social elites in the West. 相似文献
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75.
Iranian Polymer Journal - A novel class of photochromic copolymer based on spironaphthoxazine (SO) moieties was smoothly prepared through the copolymerization of methyl methacrylate (MMA), butyl... 相似文献
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79.
Yuqiang Mao Xiangning Bu Guangyuan Xie Erdong Wu Wencheng Xia 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(8):940-950
In this study, the ultrasound was fixed in the pulp zone of flotation cell and its effect on the true flotation of lignite was analyzed. Flotation results indicated that the simultaneous ultrasound treatment increased the concentrate yield and decreased the concentrate ash content. Screening analysis of flotation products revealed that the ultrasound could crush coarse coal to fine coal and scanning electron microscopy (SEM) tests indicated that the ultrasound could reduce the coverage of high-ash coal fines on the coarse particle surface. Thus, the flotation recovery of coarse lignite particle was increased. In addition, the true flotation and entrainment of ?0.074 mm fine particles were studied by the sink-float test and the method of Trahar. It was found the ultrasound significantly enhanced the true flotation of fine particles and improved the overall water recovery in lignite flotation. 相似文献
80.
Fluorescence‐Activated Cell Sorters: Standing Surface Acoustic Wave (SSAW)‐Based Fluorescence‐Activated Cell Sorter (Small 40/2018) 下载免费PDF全文