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91.
92.
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
93.
Qilin Liu Feng Ding 《International Journal of Adaptive Control and Signal Processing》2021,35(10):1970-1989
The identification of the Hammerstein–Wiener (H-W) systems based on the nonuniform input–output dataset remains a challenging problem. This article studies the identification problem of a periodically nonuniformly sampled-data H-W system. In addition, the product terms of the parameters in the H-W system are inevitable. In order to solve the problem, the key-term separation is applied and two algorithms are proposed. One is the key-term-based forgetting factor stochastic gradient (KT-FFSG) algorithm based on the gradient search. The other is the key-term-based hierarchical forgetting factor stochastic gradient (KT-HFFSG) algorithm. Compared with the KT-FFSG algorithm, the KT-HFFSG algorithm gives more accurate estimates. The simulation results indicate that the proposed algorithms are effective. 相似文献
94.
Huizhu Cai Bingbing Chen Xiao Zhang Yuchen Deng Dequan Xiao Ding Ma Chuan Shi 《Nano Research》2021,14(1):122-130
Over recent years,catalytic materials of Fe-N-C species have been recognized being active for oxygen reduction reaction(ORR).However,the identification of active site remains challenging as it generally involves a pyrolysis process and mixed components being obtained.Herein Fe3C/C and Fe2N/C samples were synthesized by temperature programmed reduction of Fe precursors in 15%CH4/H2and pure NH3,respectively.By acid leaching of Fe2N/C sample,only single sites of FeN4species were presented,providing an ideal model for identification of catalytic functions of the single sites of FeN4in ORR.A correlation was conducted between the concentration of FeⅡN4in low spin state by Mossbauer spectra and the kinetic current density at 0.8 V in alkaline media,and such a structure-performance correlation assures the catalytic roles of low spin FeⅡN4 species as highly active sites for the ORR. 相似文献
95.
Yanru Shen Yongqi Tong Yuhao Zhao Lin Zhang Shi Bu Weigang Xu Chenye Pan Hong Ding Zhengjun Yang 《Advanced Powder Technology》2021,32(6):1858-1868
Aiming at the problems of low collection efficiency of fine particulate matter and large area occupied by existing electrostatic precipitators (ESP), a new type of horizontal electrode ESP is proposed. It has the advantages of accelerating turbulent coalescence, increasing the effective dust collecting area and increasing the particle driving speed. The performance of the new type of ESP is systematic studied through simulation and experiment at the same time, and the results matches well. By comparing the dust removal effect of the horizontal electrode ESP and the conventional ESP, it can be concluded that the horizontal electrode ESP has a better dust removal efficiency, and can still maintain a better dust removal effect under high air velocity. The dust removal efficiency of new ESP can reach above 98% under the experimental conditions. 相似文献
96.
97.
正This special issue of the Chinese Journal of Chemical Engineering(CJCh E) concerns with the current progress in advanced energy technologies and materials related to chemical science and technology, especially the work in the field of renewable energy,energy storage, clean and efficient utilization of energy, aligning well to the scope of this Journal.The world is moving towards a sustainable, clean and low-carbon future via ‘Energy Transition', i.e., 相似文献
98.
Evolution of the microstructure, optical, and magnetic properties have been investigated systematically in multiferroic CuFe1-xSnxO2 (x?=?0–0.05) ceramics. Substitution of Sn4+ for Fe3+ results in expansion of CuFeO2 lattice, and reduces the density of the material, but the metal oxidation states are unchanged. Observation of the optical properties shows that the value of the direct optical band gap (Eg) decreases with increasing Sn doping level, and that the CuFe1-xSnxO2 (x?=?0–0.04) series with values >?3.1?eV. Magnetic susceptibility measurements show that Sn4+ doping decreases the Curie-Weiss temperature, i.e. weakens the strength of the antiferromagnetic interaction between high-spin Fe3+ ions, but does not affect the stability of the antiferromagnetic phase, and all samples undergo successive magnetic transitions at about TN1 =?15?K and TN2 =?11?K. However, magnetization curves show that changes occur in the magnetic interactions and both ferromagnetism and antiferromagnetism co-exist in the Sn4+-doped samples. The maximum value of the saturation magnetization of 1.8?emu·g?1 was observed for the x?=?0.03 sample in a 2.5?kOe field. The changes in the magnetic behavior are closely related to the lattice distortion and charge compensation, which are discussed in detail in this work. 相似文献
99.
100.
The analysis for morphological evolution and crystallography of degenerate pearlite in 100Mn13 steel
During approximate 773 K aging treatment of 100Mn13 steel, degenerate pearlite will occur and evolve into lamellar pearlite during growth process. The microstructures of degenerate pearlite and its evolutionary lamellar pearlite are observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that after 748 K, 773 K and 798 K aging, degenerate pearlites occur at grain boundary. At growth front of degenerate pearlite forming at 773 K and 798 K, pearlite presents a morphology of short lamellae of carbide and ferrite, indicating a trend of developing into lamellar pearlite. The higher the temperature is, the more obvious the trend is, and even a conventional lamellar pearlite has developed. However, there is no morphological evolution for degenerate pearlite forming at 748 K aging. Besides, the constituents of degenerate pearlite is identified as M23C6 and ferrite, and Kurdjumov-Sachs orientation relationship exists between them, (01 )α//( 1 )M23C6, [111]α//[110]M23C6. This orientation relationship maintains in morphological evolution from degenerate pearlite to lamellar pearlite. 相似文献