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On the Innovation,Design,Construction,and Experiments of OMEGA-Based SSPS Prototype:The Sun-Chasing Project

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Engineering 2024年第5期36卷 90-101页

作者： Baoyan Duan Yiqun zhang Guangda Chen Ze Zhao Jianwei mi Xun Li lin Yang Xi Li Research Institute on Mechatronics Xidian UniversityXi’an 710071China Research Institute of Antenna Xidian UniversityXi’an 710071China

This study systematically introduces the development of the world’s first full-link and full-system ground demonstration and verification system for the OMEGA space solar power satellite(SSPS).First,the OMEGA 2.0 innovation design was ***,field-coupling theoretical models of sunlight concentration,photoelectric conversion,and transmitting antennas were established,and a systematic optimization design method was ***,a beam waveform optimization methodology considering both a high beam collection efficiency and a circular stepped beam shape was ***,a control strategy was developed to control the condenser pointing toward the sun while maintaining the transmitting antenna toward the ***,a high-efficiency heat radiator design method based on bionics and topology optimization was ***,a method for improving the rectenna array’s reception,rectification,and direct current(DC)power synthesis efficiencies is ***,high-precision measurement technology for high-accuracy beam-pointing control was ***,a smart mechanical structure was designed and ***,the developed SSPS ground demonstration and verification system has the capacity for sun tracking,a high concentration ratio,photoelectric conversion,microwave conversion and emission,microwave reception,and rectification,and thus satisfactory results were obtained.

关键词： OMEGA-SSPS Full-link and full-system Beam collection efficiency Circular stepped beam shape Smart structure Field coupling theoretical model `Beam pointing control

Fault DiagnosisMethod of Energy Storage Unit of Circuit Breakers Based on EWT-ISSA-BP

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Energy Engineering 2024年第7期121卷 1991-2007页

作者： Tengfei Li Wenhui zhang Ke mi Qingming lin Shuangwei Zhao Jiayi Song Puneng Electric Power Technology Engineering Branch Shanghai Hengnengtai Enterprise Management Co.Ltd.Shanghai200437China School of Electrical Engineering Sichuan UniversityChengdu610065China

Aiming at the problem of energy storage unit failure in the spring operating mechanism of low voltage circuit breakers(LVCBs).A fault diagnosis algorithm based on an improved Sparrow Search Algorithm(ISSA)optimized Backpropagation Neural Network(BPNN)is proposed to improve the operational safety of *** the 1.5kV/4000A/75kA LVCB as an *** to the current operating characteristics of the energy storage motor,fault characteristics are extracted based on Empirical Wavelet Transform(EWT).Traditional BPNN has problems such as difficulty adjusting network weights and thresholds,being sensitive to initial weights,and quickly falling into local optimal *** Sparrow Search Algorithm(SSA)with self-adjusting weight factors combined with bidirectional mutations is added to optimize the selection of BPNN *** results show that the ISSA-BPNN can accurately and quickly distinguish six conditions of motor voltage reduction:motor voltage increase,motor voltage decrease,energy storage spring stuck,transmission gear stuck,regular state and energy storage spring not *** is suitable for fault diagnosis and detection of the energy storage part of LVCB.

关键词： Low voltage circuit breakers energy storage motor current sparrow search algorithm empirical wavelet transform fault diagnosis

A fast forward computational method for nuclear measurement using volumetric detection constraints

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Nuclear Science and Techniques 2024年第2期35卷 47-63页

作者： Qiong zhang lin-Lv lin University of Electronic Science and Technology of China Chengdu 610000China

Owing to the complex lithology of unconventional reservoirs,field interpreters usually need to provide a basis for interpretation using logging simulation *** the various detection tools that use nuclear sources,the detector response can reflect various types of information of the *** Monte Carlo method is one of the primary methods used to obtain nuclear detection responses in complex ***,this requires a computational process with extensive random sampling,consumes considerable resources,and does not provide real-time response ***,a novel fast forward computational method(FFCM)for nuclear measurement that uses volumetric detection constraints to rapidly calculate the detector response in various complex environments is ***,the data library required for the FFCM is built by collecting the detection volume,detector counts,and flux sensitivity functions through a Monte Carlo ***,based on perturbation theory and the Rytov approximation,a model for the detector response is derived using the flux sensitivity function method and a one-group diffusion *** environmental perturbation is constrained to optimize the model according to the tool structure and the impact of the formation and borehole within the effective detection ***,the method is applied to a neutron porosity tool for *** various complex simulation environments,the maximum relative error between the calculated porosity results of Monte Carlo and FFCM was 6.80%,with a rootmean-square error of 0.62 *** field well applications,the formation porosity model obtained using FFCM was in good agreement with the model obtained by interpreters,which demonstrates the validity and accuracy of the proposed method.

关键词： Nuclear measurement Fast forward computation Volumetric constraints

Fabrication of Al-Coated Mg-Li Alloy Sheet and Investigation of Its Properties

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Acta Metallurgica Sinica(English Letters) 2019年第2期32卷 169-177页

作者： Tian-Long zhang Toko Tokunaga Munekazu Ohno mi-lin zhang Kiyotaka Matsuura Graduate School of Engineering Hokkaido University Faculty of Engineering Hokkaido University College of Materials Science and Chemical Engineering Harbin Engineering University

An Al-coated Mg-8 mass% Li alloy rectangular bar was fabricated by hot extrusion, and then, it was hot-rolled into a thin sheet. The Al coating was uniform in thickness and had good bonding with the substrate during all the processing. This Alcoated Mg–Li alloy exhibited a good corrosion resistance in a 0.5 mass% HCl aqueous solution. No intermetallic compound was observed at the Al/Mg–Li interface after the extrusion and the rolling. The Al-coated Mg–Li alloy sheet exhibited an elongation to fracture of 35% at room temperature at a strain rate of 0.001 s(-1)without any debonding between the coating and the substrate. When tensile tested at 573 K at 0.001 s(-1)in the air, the Al coating remained undamaged even until an elongation of about 150%. Further elongation generated cracks on the coating and the specimen fractured at an elongation of about 200%. In an Ar atmosphere, the specimen exhibited a fracture elongation of over 400% under the same conditions at 573 K at 0.001 s(-1), although a large number of cracks generated on the Al coating.

关键词： Mg–Li alloy Composite material Coating Mechanical properties Superplasticity

Progress in preparation of rare earth metals and alloys by electrodeposition in molten salts

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Rare Metals 2016年第11期35卷 811-825页

作者： Wei Han Mei Li mi-lin zhang Yong-De Yan Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering University

Rare earth（RE） metals and their alloys have attracted considerable practical interests due to their functional properties. Because of their negative deposition potentials, RE metals cannot be electrochemically deposited from aqueous media. Using molten salt as medium provides a unique opportunity for the electrowinning and electrorefining of high-purity RE metals, as well as for the electrochemical formation of their alloys and intermetallic compounds. Certainly, the electrochemical behaviors of RE metals and their alloys have been investigated in a number of different molten salts comprising all-fiuorides,all-chlorides and mixed chloride-fiuoride media. Based on the results, RE and their alloys were produced by molten salt electrolysis. In this paper, the developments of preparation of RE metals and their alloys by electrolysis in molten salts in recent years were systematically summarized on both the local and international levels. Attention was paid mainly to the electrodeposition of RE metals and their alloys, including RE-Mg, RE-Al, RE-Ni, RE-Co,RE-Cu, RE-Fe and RE-Zn alloys.

关键词： Electrochemical formation Molten salts Electrolysis Rare earth Alloys

Preparation and characterization of LiAl_xMn_(2-x)O_4 for a supercapacitor in aqueous electrolyte

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International Journal of minerals,Metallurgy and Materials 2009年第1期16卷 112-118页

作者： Yun Xue Ye Chen mi-lin zhang Yong-de Yan College of Materials Science and Chemical Engineering Harbin Engineering University Harbin 150001 China

LiAlxMn2-xO4 （0≤x≤0.5） was synthesized by high temperature solid-state reaction. The structure and morphology of LiAlxMn2-xO4 were investigated by X-ray diffraction and scanning electron microscopy （SEM）. The results indicate that all samples show spinel phase. The polyhedral particles turn to club-shaped, then change to small spherical, and finally become agglomerates with increasing Al content. The supercapacitive performances of LiAlxMn2-xO4 were studied by means of galvanostatic charge-discharge, cyclic voltammetry, and alternating current （AC） impedance in 2 mol·L^-1 （NH4）2SO4 aqueous solution. The results show that LiAlxMn2-xO4 represents rectangular shape performance in the potential range of 0-1 V. The capacity and cycle performance can be improved by doping Al. The composition of x=0.1 has the maximum special capacitance of 160 F·g^-1, which is 1.37 times that of LiMn2O4 electrode. The capacitance loss of LiAlxMn2-xO4 with x=0.1 is only about 14% after 100 cycles.

关键词： supercapacitor electrode materials aqueous electrolyte spinel

Multidimensional coupled structure-activity relationship models for replacement of SF_(6)

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High Voltage 2024年第2期9卷 484-494页

作者： mi zhang Hua Hou Baoshan Wang College of Chemistry and Molecular Sciences Wuhan UniversityWuhanChina

Computational screening of single gases to replace SF_(6)for electrical insulation has been challenged by the difficulty in combining various mutually exclusive properties especially for dielectric performance with liquefaction and environmental *** reveal the inherent correlations between dielectric strength(Er),boiling point(Tb),and global warming potential(GWP)of dielectric materials,a coupled structure-activity relationship(CSAR)model has been proposed for the first *** means of the generic descriptors,as deduced from the electrostatic potentials,and the specific descriptors,as introduced from the respective microscopic mechanisms,the complex interdependence between Er,Tb,and GWP of the insulation gases is quantitatively characterised by the 3-D coupling *** coupling mechanism for the right balance of properties is uncovered in terms of the first-principle *** CSAR model outperforms the previous SAR models in predicting Er,Tb,and GWP simultaneously in a self-consistent *** importantly,the concept of CSAR could be extended readily to any multidimensional macroscopic *** replacement compounds have been identified tentatively to be the promising candidates to replace SF_(6)using the CSAR model.

关键词： properties. dielectric insulation

The role of vitamin E in polyunsaturated fatty acid synthesis and alleviating endoplasmic reticulum stress in sub-adult grass carp(Ctenopharyngodon idella)

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Animal Nutrition 2024年第1期16卷 275-287页

作者： Ke Yao lin Feng Wei-Dan Jiang Yang Liu Lu zhang Hai-Feng mi Xiao-Qiu Zhou Pei Wu Animal Nutrition Institute Sichuan Agricultural University Fish Nutrition and Safety Production University Key Laboratory of Sichuan Province Sichuan Agricultural University Key Laboratory of Animal Disease-Resistance Nutrition Ministry of Education Ministry of Agriculture and Rural Affairs Key Laboratory of Sichuan Province Tongwei Co. Ltd. Healthy Aquaculture Key Laboratory of Sichuan Province

Vitamin E(VE) is an essential lipid-soluble vitamin that improves the fish flesh quality. However, the underlying molecular mechanisms remain unclear. This study aimed to investigate the effects of VE on growth performance and flesh quality in sub-adult grass carp(Ctenopharyngodon idella). A total of 450fish(713.53 ± 1.50 g) were randomly divided into six treatment groups(three replicates per treatment)and fed for nine weeks with different experimental diets(dietary lipid 47.8 g/kg) that contained different levels of VE(5.44, 52.07, 96.85, 141.71, 185.66, and 230.12 mg/kg diet, supplemented as dl-a-tocopherol acetate). Notably, the treatment groups that were fed with dietary VE ranging from 52.07 to230.12 mg/kg diet showed improvement in the percent weight gain, special growth rate, and feed efficiency of grass carp. Moreover, the treatment groups supplemented with dietary VE level of 141.71,185.66, and 230.12 mg/kg diet showed enhancement in crude protein, lipid, and a-tocopherol contents in the muscle, and the dietary levels of VE ranging from 52.07 to 141.71 mg/kg diet improved muscle pH24h and shear force but reduced muscle cooking loss in grass carp. Furthermore, appropriate levels of VE(52.07 to 96.85 mg/kg diet) increased the muscle polyunsaturated fatty acid content in grass carp. Dietary VE also increased the mRNA levels of fatty acid synthesis-related genes, including fas, scd-1, fad,elovl, srebp1, pparγ, and lxra, and up-regulated the expression of SREBP-1 protein. However, dietary VE decreased the expression of fatty acid decomposition-related genes, including hsl, cpt1, acox1, and ppara,and endoplasmic reticulum stress-related genes, including perk, ire1, atf6, eif2a, atf4, xbp1, chop, and grp78, and down-regulated the expression of p-PERK, p-IRE1, ATF6, and GRP78 proteins. In conclusion,dietary VE increased muscle fatty acid synthesis, which may be partly associated with the alleviation of endoplasmic reticulum stress, and ultimately improves fish fles

关键词： Vitamin E Flesh quality Muscle polyunsaturated fatty acid level Endoplasmic reticulum stress Growth performance Grass carp

Impacts of Roof/Ground mitigation Strategies on Improving the Urban Thermal Environment and Human Comfort over the Yangtze River Delta, China

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Journal of Meteorological Research 2024年第1期38卷 108-125页

作者： Hongyun MA mi zhang Haishan CHEN Yan WANG Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)/Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC)Nanjing University of Information Science&TechnologyNanjing 210044 School of Atmospheric Sciences Nanjing UniversityNanjing 210023 Experimental Teaching Center for Meteorology and Environment Nanjing University of Information Science&TechnologyNanjing 210044

The combined effects of global warming and the urban heat islands exacerbate the risk of urban heat stress. It is crucial to implement effective cooling measures in urban areas to improve the comfort of the thermal environment. In this study, the Weather Research and Forecasting Model(WRF), coupled with a single-layer Urban Canopy Model(UCM), was used to study the impact of heat mitigation strategies. In addition, a 5-km resolution land-cover dataset for China(ChinaLC), which is based on satellite remote sensing data, was adjusted and used, and 18 groups of numerical experiments were designed, to increase the albedo and vegetation fraction of roof/ground parameters. The experiments were conducted for four heatwave events that occurred in the summer of 2013 in the Yangtze River Delta urban agglomeration of China. The simulated results demonstrated that, for the single roof/ground schemes, the mitigation effects were directly proportional to the albedo and greening. Among all the experimental schemes, the superposed schemes presented better cooling effects. For the ground greening scheme, with similar net radiation flux and latent heat flux, its storage heat was lower than that of the roof greening scheme, resulting in more energy flux into the atmosphere, and its daytime cooling effect was not as good as that of the roof greening scheme. In terms of human thermal comfort(HTC), the improvement achieved by the ground greening scheme was better than any other single roof/ground schemes, because the increase in the relative humidity was small. The comprehensive evaluation of the mitigation effects of different schemes on the thermal environment presented in this paper provides a theoretical basis for improving the urban environment through rational urban planning and construction.

关键词： urban heat island human thermal comfort urban canopy mitigation strategies Yangtze River Delta Weather Research and Forecasting Model(WRF) Urban Canopy Model(UCM)