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Astrodynamics 2024年第2期8卷 261-269页

作者： zhixiong Ji Gefei shi School of Aeronautics and Astronautics Sun Yat-sen UniversityGuangzhou 510275China Shenzhen Campus of Sun Yat-sen university Shenzhen 518107China Shenzhen Key Laboratory of Intelligent Microsatellite Constellation Shenzhen 518107China

This study proposes a novel adaptive neural dynamic-based hybrid control strategy for stable subsatellite retrieval of two-body tethered satellite *** retrieval speed is given analytically,ensuring a libration-free steady *** mitigate the potential libration motion,a general control input signal is generated by an adaptive neural-dynamic(AND)algorithm and executed by adjusting the retrieval speed and thruster on the *** address the limited retrieval speed and improve the control performance,the thruster controller is manipulated according to a novel advanced state fuzzy control law based on higher-order libration states,whereas the remaining control input is allocated to the speed *** Lyapunov stability of the control strategy is demonstrated *** simulations validate the proposed control strategy,demonstrating well-allocated control inputs for both controllers and good control performance.

关键词： tethered satellite system(TSS) stable retrieval hybrid control adaptive neural-dynamic (AND)control fuzzy control

Your personal choices in transportation and food are important for lowering carbon emissions

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Frontiers of Environmental science & engineering 2024年第6期18卷 27-32页

作者： Bruce Logan fang Zhang Wulin Yang Le shi Institute of Energy and the Environment The Pennsylvania State UniversityUniversity ParkPA 16802USA School of Environment Tsinghua UniversityBeijing 100084China college of Environmental sciences and engineering Peking UniversityBeijing 100871China college of Environmental and resource sciences Zhejiang UniversityHangzhou 310058China

There is a global need to reduce greenhouse gas emissions to limit the extent of climate change.A better understanding of how our own activities and lifestyle influence our energy use and carbon emissions can help us enable changes in activities that can lead to reductions in carbon *** we discuss an approach based on examining carbon emissions from the perspective of the unit C,where 1 C is the CO_(2)from food a person would on average eat every *** approach shows that total CO_(2)emissions in china,normalized by the population,is 22.5 C while carbon emissions for a person in the US is 43.9 C.A better appreciation of our own energy use can be obtained by calculating carbon emissions from our own activities in units of C,for example for driving a car gasoline or electric vehicle a certain number of kilometers,using electricity for our homes,and eating different *** this information,we can see how our carbon emissions compare to national averages in different countries and make decisions that could lower our personal CO_(2)emissions.

关键词： Carbon dioxide Climate change Daily energy Greenhouse gas

Decabromodiphenyl ether induces the chromosome association disorders of spermatocytes and deformation failures of spermatids in mice

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Journal of Environmental sciences 2024年第4期138卷 531-542页

作者： Jinglong Xue Xiangyang Li Yafei Chi Leqiang Gao Yue Zhang Yan Wang Moxuan Zhao Jialiu Wei zhixiong shi Xianqing Zhou Department of Toxicology and Hygienic Chemistry School of Public HealthCapital Medical UniversityBeijing 100069China Beijing Key Laboratory of Environmental Toxicology Capital Medical UniversityBeijing 100069China Laboratory Animal Center Capital Medical UniversityBeijing 100069China Key Laboratory of Cardiovascular Epidemiology&Department of Epidemiology Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China

The environmental presence of decabromodiphenyl ether(BDE-209),which is toxic to the male reproductive system,is *** current study investigated its mechanism of toxicity in *** results showed,that BDE-209 induced DNA damage,decreased the expression of the promoter of meiosis spermatogenesis-and oogenesis-specific basic helix-loop-helix 1(Sohlh1),meiosis related-factors Lethal(3)malignant brain tumor like 2(L3MBTL2),pIWI-like protein 2(MILI),Cyclin-dependent kinase 2(CDK2),Cyclin A,synaptonemal complex protein 1(SYCp1)and synaptonemal complex protein 3(SYCp3),and caused spermatogenic cell apoptosis,resulting in a decrease in sperm quantity and ***,BDE-209 downregulated the levels of anaphase-promoting complex/cyclosome(ApC/C),increased the expression of pIWI-like protein 1(MIWI)in the cytoplasm of elongating spermatids,and decreased the nuclear levels of rING finger protein 8(rNF8),ubiquitinated(ub)-H2A/ub-H2B,and protamine 1(prM1)/protamine 2(prM2),while increasing H2A/H2B nuclear levels in *** reproductive toxicity was persistent for 50 days following the withdrawal of BDE-209 *** results suggested that BDE-209 inhibits the initiation of meiosis by decreasing the expression of ***,the reduced expression of L3MBTL2 inhibited the formation of chromosomal synaptonemal complexes by depressing the expression of meiosis regulators affecting the meiotic progression and also inhibited histone ubiquitination preventing the replacement of histones by protamines,by preventing rNF8 from entering nuclei,which affected the evolution of spermatids into mature sperm.

关键词： BDE-209 Meiosis L3MBTL2 Sperm rNF8 Histone ubiquitination

Facet-dependent activation of oxalic acid over hematite nanocrystals under the irradiation of visible light for efficient degradation of pollutants

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Journal of Environmental sciences 2024年第8期142卷 204-214页

作者： zhixiong Yang Yuan Li Xiaotian Wang Jiaming Li Jiquan Wang Gaoke Zhang Hubei Key Laboratory of Mineral resources processing and Environment State Key Laboratory of Silicate Materials for ArchitecturesWuhan University of TechnologyWuhan 430070China Hubei engineering Consulting Co. Ltd.Wuhan 430071China

Naturally occurring hematite has been widely studied in the Fenton-like system for water pollutant remediation due to its abundance and ***,its inadequate catalytic activity results in difficulty in effectively degrading pollutants in the catalytic degradation system that it ***,we constructed a photochemical system composed of hematite with{001}facet of high activity facet and low-cost and non-toxic oxalic acid(OA)for the removal of various types of *** removal rate for the degradation of metronidazole,tetracycline hydrochloride,rhodamine B,and hexavalent chromium by hematite nanoplate with the exposed{001}facet activating OA under visible light irradiation was 4.75,2.25,2.33,and 2.74 times than that by the exposed{110}facet,*** functional theory(DFT)calculation proved that the OA molecule was more easily adsorbed on the{001}facet of hematite than that on the{110}facet,which would favor the formation of the more Fe(Ⅲ)-OA complex and reactive *** addition,the reactive site of metronidazole for the attraction of radicals was identified on the basis of the DFT calculation on the molecular occupied orbitals,and the possible degradation pathway for metronidazole included carbon chain fracture,hydroxyethyl-cleavage,denitrogenation,and ***,this finding may offer a valuable direction in designing an efficient iron-based catalyst based on facet engineering for the improved activity of Fenton-like systems such as OA activation.

关键词： Hematite Facet exposure Oxalic acid activation Fenton-like system pollutant removal

Long-wave infrared emission properties of strain-balanced InAs/InxGa1-xAsySb1-y type-Ⅱ superlattice on different substrates

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rare Metals 2024年第7期43卷 3194-3204页

作者： Chao shi Xuan fang Hong-Bin Zhao Deng-Kui Wang Xi Chen Dan fang Dong-Bo Wang Xiao-Hua Wang Jin-Hua Li State Key Laboratory of High power Semiconductor Lasers School of PhysicsChangchun University of Science and Technology State Key Laboratory of Advanced Materials for Smart Sensing China General Research Institute for Nonferrous Metals Department of Opto-Electronic Information science School of Materials Science and EngineeringHarbin Institute of Technology

High-performance type-Ⅱ superlattices of Ⅲ-Ⅴsemiconductor materials play an important role in the development and application of infrared optoelectronic *** the quality of epitaxial materials and clarifying the luminescent mechanism are of great significance for practic al applic *** this work,strain-balanced and high-quality In As/InxGa1-xAsySb1-ysuperlattices without lattice mismatch were achieved on InAs and GaSb substrates *** grown on In As substrate could exhibit higher crystal quality and surface flatness based on high-resolution X-ray diffraction（HrXrD） and atomic force microscopy（AFM） measurements' ***,the strain distribution phenomenon from geometric phase analysis indicates that fluctuations of alloy compositions in superlattices on GaSb substrate are more *** addition,the optical properties of superlattices grown on different substrates are discussed *** of the difference in fluctuations of element composition and interface roughness of superlattices on different substrates,the superlattices grown on In As substrate would have higher integral intensity and narrower full-width at half maximum of long-wave infrared ***,the thermal quenching of emission intensity indicates that the superlattices grown on the In As substrate have better recombination ability,which is beneficial for increasing the operating temperature of infrared optoelectronic devices based on this type of superlattices.

关键词： photoluminescence Alloy compositions fluctuations InAs(Sb)/In x Ga 1− x As y Sb 1− y Type-II superlattice Substrate

Effect of electrical parameters and slag system on macrostructure of electroslag ingot

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china Foundry 2024年第1期21卷 44-50页

作者： Bing-jie Wang Yu Wang Meng-jun Wang Lei Zhao Li-zhong Chang Xiao-fang shi School of Metallurgy engineering Anhui University of TechnologyMa'anshan 243002AnhuiChina

To investigate the influence of electric parameters and slag system on the solidification quality of electroslag ingot during electroslag remelting,different power supply modes,current strengths and remelting slag systems were used to conduct electroslag remelting experiments on 304L austenitic stainless steel,and the macrostructure of electroslag ingots was *** results indicate that the depth of the metal pool decreases with the reduction of remelting frequency in the low frequency power supply *** effects of different power supply modes,such as low-frequency,direct current straight polarity(DCSp),and direct current reverse polarity(DCrp),on reducing the depth of the metal pool increase in that *** reducing the remelting current strength in the same power supply mode,the depth of metal pool is *** compared to the binary slag system of 70%CaF2+30%Al2O3,the ternary slag system of 60%CaF2+20%Al2O3+20%CaO is more effective in reducing the depth of the metal pool during *** the 60%CaF2+20%Al2O3+20%CaO ternary slag system results in a shallower and flatter metal pool,with columnar crystal growth occurring closer to the axial *** effect is observed for both low frequency and direct current(DC)power supply modes.

关键词： electroslag remelting frequency slag system solidification quality

A biased edge enhancement method for truss-based community search

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Frontiers of Computer science 2024年第3期18卷 251-253页

作者： Yuqi LI Tao MENG zhixiong HE Haiyan LIU Keqin LI School of Computer and Information engineering Central South University of Forestry and TechnologyChangsha 410082China School of Business Central South University of Forestry and TechnologyChangsha 410082China college of Information engineering Changsha Medical UniversityChangsha 410219China Department of Computer science State University of New YorkNew York 12561USA

1 Introduction A related study called community search,whose target is to find dense subgraphs containing the given node,has drawn a growing amount of attention recently[1].To explore the higher-order structure of complex networks,truss-based community search methods[2]have been ***,the truss-based hypergraph constructed from the original graph is frequently fragmented and consists of numerous subgraphs and isolated nodes[3],which boils down to the fact that these methods often pay only attention to the truss connections but ignore the lower-order connectivity of the original graph.

关键词： graph. truss connectivity

Dynamic recrystallization behavior and strengthening mechanism of a novel Mo-Ti3AlC2 alloy at ultrahigh temperature

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rare Metals 2024年第8期43卷 3946-3960页

作者： Lu Yang Xin-Yuan Zheng Yang Zhao Xi-ran Wang fang-Nao Xiao shi-Zhong Wei School of Materials science and engineering Henan University of Science and Technology National Joint engineering research Center for Abrasion Control and Molding of Metal Materials Henan University of Science and Technology Department of Applied Mechanics Univ.Bourgogne FrancheComteFEMTO-ST InstituteCNRS/UF/ENSMM/UTBM

Increasing the recrystallization temperature to achieve better high-temperature performance is critical in the development of molybdenum alloys for ultrahightemperature applications,such as the newest generation of multitype high-temperature nuclear *** this study,an innovative strategy was proposed to improve the performance of molybdenum alloys at high temperature by using the two-dimensional MAX（where M is an early transition metal,A is an A-group element and X is C or N）ceramic material *** relationships between flow stress,strain rate and temperature were *** microstructure,distribution of misorientation and evolution of dislocations in the Mo-Ti3AlC2alloy were *** microscopic mechanism of the Ti3AlC2phase in the molybdenum alloy at high temperatures was *** experimental results showed that the peak flow stress of Mo-Ti3AlC2at 1600℃ reached 155 Mpa,which was161.8% greater than that of pure *** activation energy of thermal deformation of Mo-Ti3AlC2was as large as537 kJ·mol-1,which was 17.6% more than that of pure *** recrystallization temperature reached 1600℃ or even *** topological reaction of the Ti3AlC2phase consumed a large amount of energy at high temperatures,resulting in increases in the deformation activation *** structures of AlTi3and Ti-O Magneli-phase oxides(Ti_nO2n-1) were formed in-situ,which relied on kink bands and interlayer slip,resulting in many dislocations during ***,the special two-dimensional of the structure Ti3AlC2ceramic inhibited the recrystallization behavior of the Mo *** results of this study can provide theoretical guidance for the development of a new generation of molybdenum alloys for use in ultrahigh-temperature environments.

关键词： Mo alloy Two-dimensional reinforcement Dynamic recrystallization behavior Hot deformation Mechanical properties

A NOVEL INTErprETATION OF CONCENTrATION DEpENDENCE OF VISCOSITY OF DILUTE pOLYMEr SOLUTION

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Chinese Journal of polymer science 2000年第1期18卷 57-67页

作者： Yan pan rong-shi Cheng college of Material science and engineering, south china university of technology, guangzhou 510641, china college of Chemistry and Chemical engineering, Nanjing university, Nanjing 210093, china 华南理工大学广东广州

The concentration dependence of the reduced viscosity of dilute polymer solution is interpreted in the light of a new concept of the self-association of polymer chains in dilute solution. The apparent self-association constant is defined as the molar association constant divided by the molar mass of individual polymer chain and is numerically interconvertible with the Huggins coefficient. The molar association constant is directly proportional to the effective hydrodynamic volume of the polymer chain in solution and is irrespective of the chain architecture. The effective hydrodynamic volume accounts for the non-spherical conformation of a short polymer chain in solution and is a product of a shape factor and hydrodynamic volume. The observed enhancement of Huggins coefficient for short chain and branched polymer is satisfactorily interpreted by the concept of self-association. The concept of self-association allows us to predict the existence of a boundary concentration C-s(dynamic contact concentration) which divides the dilute polymer solution into two regions.

关键词： self-association polymer solution viscosity concentration dependence