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Selection of the best initial orbital elements of satellite based on fuzzy integration evaluation method

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Journal of Systems Engineering and Electronics 2006年第3期17卷 566-570页

作者： Yang Yong'an zhang hongwei Feng Zuren Luo Yongjin Xi'an Jiaotong Univ. Xi'an 710049 P. R. China Xi'an Satellite Control Center Xi'an 710043 P. R. China

The fuzzy integration evaluation method （FIEM） is studied in order to select the best orbital elements from the multi-group initial orbits determined by a satellite TT＆C （Tracking, Telemetry and Control） center with all kinds of data sources. By employing FIEM together with the experience of TT＆C experts, the index system to evaluate the selection of the best initial orbits is established after the data sources and orbit determination theories are studied. Besides, the concrete steps in employing the method are presented. Moreover, by taking the objects to be evaluated as evaluation experts, the problem of how to generate evaluation matrices is solved. Through practical application, the method to select the best initial orbital elements has been proved to be flexible and effective The originality of the method is to find a new evaluation criterion （comparing the actually tracked orbits） replacing the traditional one （comparing the nominal orbits） for selecting the best orbital elements.

关键词： system engineering fuzzy integration evaluation method satellite initial orbit TT&C system.

Migration and transformation of Sb are affected by Mn(Ⅲ/Ⅳ)associated with lepidocrocite originating from Fe(Ⅱ)oxidation

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Journal of Environmental Sciences 2022年第5期34卷 308-318页

作者： Yalu Shao Qian Sun Liangkai Wang Weiyong Zhan hongwei zhang Hua Zhong State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China School of Agriculture and Food The University of MelbourneVictoria 3010Australia College of Agricultural Sciences and Engineering Hohai UniversityNanjing 210098China

Antimony(Sb)is a recognized priority pollutant with toxicity that is influenced by its mi-gration and transformation *** of Fe(Ⅱ)to Fe(Ⅲ)oxides,which is a com-mon phenomenon in the environment,is often accompanied by the formation of Mn(Ⅲ/Ⅳ)and might affect the fate of *** this study,incorporated Mn(Ⅲ)and sorbed/precipitated Mn(Ⅲ/Ⅳ)associated with lepidocrocite were prepared by adding Mn(Ⅱ)during and after Fe(Ⅱ)oxidation,respectively,and the effects of these Mn species on Sb fate were *** results indicated that the association of these Mn species with lepidocrocite obviously enhanced Sb(Ⅲ)oxidation to Sb(V),while concomitantly inhibiting Sb sorption due to the lower sorption capacity of lepidocrocite for Sb(V)than Sb(Ⅲ).Additionally,Mn oxide equivalents increased in the presence of Sb,indicating that Sb oxidation by Mn(Ⅲ/Ⅳ)associated with lepidocrocite was a continuous recycling process in which Mn(Ⅱ)released from Mn(Ⅲ/Ⅳ)reduction by Sb(Ⅲ)could be oxidized to Mn(Ⅲ/Ⅳ)*** recycling pro-cess was favorable for effective Sb(Ⅲ)***,Sb(Ⅴ)generated from Sb(Ⅲ)ox-idation by Mn(Ⅲ/Ⅳ)enhanced Mn(Ⅱ)sorption at the beginning of the process,and thus favored Mn(Ⅲ/Ⅳ)formation,which could further promote Sb(Ⅲ)oxidation to Sb(V).Over-all,this study elucidated the effects of Mn(Ⅲ/Ⅳ)associated with lepidocrocite arisen from Fe(Ⅱ)oxidation on Sb migration and transformation and revealed the underlying reaction mechanisms,contributing to a better understanding of the geochemical dynamics of Sb.

关键词： Antimony Manganese Lepidocrocite Sorption Oxidation

Effects of a novel bimetallic catalytic biofilter-based pretreatment technique on the form of ultrafiltration membrane fouling

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Chinese Journal of Chemical Engineering 2020年第10期28卷 2513-2522页

作者： Songze Hao Xuehui Zhao hongwei zhang Yun Wu Cheng Fang Xujia Wang State Key Laboratory of Separation Membrane and Membrane Process Tiangong UniversityTianjin 300387China School of Materials Science and Engineering Tiangong UniversityTianjin 300387China School of Environmental Science and Engineering Tiangong UniversityTianjin 300387China

Pretreatments of influents using bimetallic catalytic biofilter(BC-biofilter)can help reduce transmembrane *** ultrafiltration membranes coupled with a conventional biofilter pretreatment,the cake layer resistance accounts for 25.0%of the total ***,for those coupled with BC-biofilter pretreatment,the cake layer resistance accounts only for 12.5%of the total *** laser scanning microscopy is employed to determine the porosity of cake *** is found that ultrafiltration membranes with BC-biofilter pretreatment show a cake layer porosity of up to 0.56 or greater,whereas those with a conventional biofilter pretreatment exhibit a cake layer porosity of only *** is because micro-flocculation occurs in the effluents of *** flocs generated through flocculation deposit on membrane surfaces to create highly porous cake ***,catalytic reduction can increase the zeta potentials of the biofilter *** makes the deposition of colloidal particles and flocs on membrane surfaces difficult under electrostatic ***,micro-flocculation after BC-biofilter pretreatment can remove colloidal particles with particle sizes of200–350 nm in *** can effectively prevent the blockage of ultrafiltration membrane ***,compared to conventional biofilter,BC-biofilter pretreatment can more effectively reduce the number of colloidal particles and the van der Waals forces of ultrafiltration *** can also change the action directions of electric double layers and thereby mitigate ultrafiltration membrane fouling.

关键词： Catalytic reduction Micro-flocculation Cake layer Membrane pore Membrane fouling

Biosynthetic CdS-Thiobacillus thioparus hybrid for solar-driven carbon dioxide fixation

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Nano Research 2023年第4期16卷 4531-4538页

作者： Guangyu Liu Feng Gao hongwei zhang Lei Wang Chao Gao Yujie Xiong Hefei National Laboratory for Physical Sciences at the Microscale and School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China Institute of Energy Hefei Comprehensive National Science Center350 Shushanhu Rd.Hefei 230031China State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Synergistically combining biological whole-cell bacteria with man-made semiconductor materials innovates the way for sustainable solar-driven CO_(2)fixation,showing great promise to break through the bottleneck in traditional chemical photocatalyst ***,most of the biohybrids require uneconomical organic nutrients and anaerobic conditions for the successful cultivation of the bacteria to sustain the CO_(2)fixation,which severely limits their economic viability and applicability for practical ***,we present an inorganic-biological hybrid system composed of obligate autotrophic bacteria Thiobacillus thioparus(***)and CdS nanoparticles(NPs)biologically precipitated on the bacterial surface,which can achieve efficient CO_(2)fixation based entirely on cost-effective inorganic salts and without the restriction of anaerobic *** optimized interface between CdS NPs and *** formed by biological precipitation plays an essential role for *** efficiently receiving photogenerated electrons from CdS NPs and thus changing the autotrophic way from chemoautotroph to *** a result,the *** biohybrid realizes the solar-driven CO_(2)fixation to produce multi-carbon glutamate synthase and biomass under visible-light irradiation with CO_(2)as the only carbon *** work provides significant inspiration for the further exploration of the solar-driven self-replicating biocatalytic system to achieve CO_(2)fixation and conversion.

关键词： biohybrids solar-driven CO_(2)fixation carbon cycle autotrophic bacteria Thiobacillus thioparus cadmium sulfide

Corrosion mechanisms of Zr-based bulk metallic glass in NaF and NaCl solutions

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Journal of Materials Science & Technology 2020年第11期42卷 33-43页

作者： zhangweijia Qiu Zhengkun Li Huameng Fu hongwei zhang Zhengwang Zhu Aimin Wang Hong Li Long zhang Haifeng zhang School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shenyang National Laboratory for Material Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Shenyang Amorphous Metal Manufacturing Co. LtdShenyang 110000China Dongguan Eontec Co. LtdDongguan 523662China

So far,some investigations related to the corrosion mechanism of Zr-based metallic glasses in solutions containing Cl-have been ***,few attentions have been paid to the situation in F--containing *** paper describes the corrosion behaviours of Zr52Al10Ni6Cu32 bulk metallic glass(BMG)in Na F and Na Cl aqueous *** corrosion mechanism of Zr-based BMG in F–containing solution was proposed for the first *** was found that in Na Cl solutions,Zr-based BMG samples underwent typical pitting *** dissolution of Zr,Al and enrichment of Cu were observed in corrosion ***,corrosion occurred in the form of general breakdown of passive film in Na F *** difference is interpreted in terms of the binding ability of anions to surrounding molecules,i.e.,Cl-with loose surrounding water passes through the passive film to cause pitting;F-with a tight surrounding molecules layer absorbs on passive film then coordinates with cations from matrix.

关键词： Metallic glass Zirconium Corrosion behavior Pitting corrosion Passivation

Simultaneous enhancement of strength and ductility of body-centered cubic TiZrNb multi-principal element alloys via boron-doping

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Journal of Materials Science & Technology 2021年第19期78卷 74-80页

作者： Jingyu Pang hongwei zhang Long zhang Zhengwang Zhu Huameng Fu Hong Li Aimin Wang Zhengkun Li Haifeng zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Material Science and Engineering University of Science and Technology of ChinaShenyang 110016 China Ji Hua Laboratory in Foshan China

Body-centered cubic(BCC)multi-principal element alloys(MPEAs)have intrinsic high strength but poor ductility,which greatly limits their potential *** we present the boron-doping strategy to enhance the strength and ductility of TiZrNb MPEAs *** yield strength and ductility of the TiZrNb MPEA with boron addition of 500 ppm are increased by 19.0%and 48.7%compared to the boron-free TiZrNb MPEA,***-doping induced high efficiency in grain refinement from~96.0μm to~16.2μm is the main factor for *** dominated deformation mechanism involving cross slip and dislocation pining in the TiZrNb containing 500 ppm boron serves to enhance the strain-hardening capacity,resultant the enhancement of ductility from 7.8%to 11.6%.While the planar slip of dislocations is the dominated deformation mechanism for the boron-free TiZrNb.

关键词： Boron-doping TiZrNb Grain refinement Strain-hardening capacity Deformation mechanism

Short‑Term Splitting and Long‑Term Stability of Cuboidal Nanoparticles in Ni_(44)Co_(22)Cr_(22)Al_(6)Nb_(6) Multi‑Principal Element Alloy

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Acta Metallurgica Sinica(English Letters) 2023年第6期36卷 999-1006页

作者： Yitong Yang Jingyu Pang hongwei zhang Aimin Wang Zhengwang Zhu Hong Li Guangquan Tang Long zhang Haifeng zhang Shi‑Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Material Science and Engineering University of Science and Technology of ChinaShenyang 110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Liaoning Zhongke Boyan Technology Co. Ltd.Fushun 113001China Foshan Huizhen Technology Co. Ltd.Foshan 528200China

Multi-principal element alloys(MPEAs)composed of thermally stable high-density cuboidal nanoparticles have revealed great potential for high-temperature *** this work,we systematically studied the growth behavior and coarsening kinetics of the cuboidal nanoparticles in Ni_(44)Co_(22)Cr_(22)Al_(6)Nb_(6) *** the initial stage of isothermal aging,the nanoparticles exhibit growth and split behavior,resulting in the improvement of mechanical performance,then the cuboidal nanoparticles retain superior thermal and mechanical stability during long-term isothermal *** 288 kJ/mol activation energy of Ni_(44)Co_(22)Cr_(22)Al_(6)Nb_(6) MPEA,which is higher than that in Ni-based superalloys,reveals the obvious elemental sluggish diffusion in Ni_(44)Co_(22)Cr_(22)Al_(6)Nb_(6) ***,coarsening rate constant determined by the volume diffusion mechanism in Ni_(44)Co_(22)Cr_(22)Al_(6)Nb_(6) MPEA is 1–2 orders of magnitude less than that of the traditional Ni-based *** shortterm regulation and long-term stability of the cuboidal nanoparticles endow the Ni_(44)Co_(22)Cr_(22)Al_(6)Nb_(6) MPEA with superior mechanical performance and thermal stability for high temperature applications.

关键词： Multi-principal element alloy L1_(2)nanoparticles Thermal stability Coarsening kinetics

Experimental study on moving boundaries of fluid flow in porous media

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Chinese Science Bulletin 2008年第16期53卷 2438-2445页

作者： ZHOU hongwei zhang YaHeng LI AiMin QIU DaYong Institute of Rock Mechanics and Fractals China University of Mining and Technology Beijing 100083 China

Researches on the boundary shape of fluid flow in porous media play an important role in engineering practices, such as petroleum exploitation, nuclear waste disposal and groundwater contamination. In this paper, six types of artificial porous samples (emery jade) with different porosities are manufactured. With the background of slow flow in porous media, laboratory experiments are carried out by observing the movement of five types of fluids with different dynamic viscosities in various types of porous media. A digital video recorder is employed to record the complete process of the fluid flow in the porous media. Based on the digital photos of the moving boundaries of fluid flow in porous media, the average displacement and fractal dimension of the moving boundary are estimated for different combinations of porosity and dynamic viscosity. Moreover, the evolution behavior of the average velocity and fractal dimension of the moving boundary with time is known. The statistical relations of the average velocity, the fractal dimension of the moving boundary and the porosity of porous media and the dynamic vis- cosity of fluids are proposed in this paper. It is shown that the front shape of the moving boundary of fluid flow in porous media is an integrated result of the porosity of porous media and the dynamic viscosity of fluids.

关键词：多孔渗水介质流程移动边界石油

Radar automatic target recognition based on feature extraction for complex HRRP

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Science in China(Series F) 2008年第8期51卷 1138-1153页

作者： DU Lan LIU hongwei BAO Zheng zhang JunYing National Laboratory of Radar Signal Processing Xidian University Xi'an 710071 China

Radar high-resolution range profile （HRRP） has received intensive attention from the radar automatic target recognition （RATR） community. Usually, since the initial phase of a complex HRRP is strongly sensitive to target position variation, which is referred to as the initial phase sensitivity in this paper, only the amplitude information in the complex HRRP, called the real HRRP in this paper, is used for RATR, whereas the phase information is discarded. However, the remaining phase information except for initial phases in the complex HRRP also contains valuable target discriminant information. This paper proposes a novel feature extraction method for the complex HRRP. The extracted complex feature vector, referred to as the complex feature vector with difference phases, contains the difference phase information between range cells but no initial phase information in the complex HRRR According to the scattering center model, the physical mechanism of the proposed complex feature vector is similar to that of the real HRRP, except for reserving some phase information independent of the initial phase in the complex HRRP. The recognition algorithms, frame-template establishment methods and preprocessing methods used in the real HRRP-based RATR can also be applied to the proposed complex feature vector-based RATR. Moreover, the components in the complex feature vector with difference phases approximate to follow Gaussian distribution, which make it simple to perform the statistical recognition by such complex feature vector. The recognition experiments based on measured data show that the proposed complex feature vector can obtain better recognition performance than the real HRRP if only the cell interval parameters are properly selected.

关键词： complex high-resolution range profile (HRRP) radar automatic target recognition (RATR) feature extraction minimum Euclidean distance classifier adaptive Gaussian classifier (AGC)