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Journal of Environmental Sciences 2024年第2期136卷 213-225页

作者： Bowen Xu Jiaxin Qu Xueqian Wang Langlang Wang Yu Pu Ping Ning Yibing Xie Yixing Ma Qiang Ma Faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming 650500China school of Architecture and Civil Engineering Chengdu UniversityChengdu 610106China

To investigate the enhancing effect of Mn on the performance of simultaneous catalytic oxidation of AsH_(3)and PH_(3)by CuO-Al_(2)O_(3)in a reducing atmosphere under micro-oxygen conditions,Cu-Mn modifiedγ-Al_(2)O_(3)catalysts were prepared.The characteristics of the catalysts showed that Mn reduced the crystallinity of the active CuO component,increased the number of oxygen vacancies and acidic sites on the catalyst surface,enhanced the mobility of surface oxygen,and the interaction between copper and manganese promoted the redox cycling ability of the catalysts and improved their oxidation performance,which increased the conversion frequency(TOF)by 2.54×10^(-2)to 3.07×10^(-2)sec^(-1).On the other hand,the introduction of Mn reduced the production of phosphate and As_(2)O_(3)on the catalyst surface by30.96%and 44.9%,which reduced the coverage and inerting of the active sites by phosphate and As_(2)O_(3),resulting in an 8 hr(6 hr)improvement in the stability of PH_(3)(AsH_(3))removal.

关键词： AsH_(3)-PH_(3)removal Oxygen activation Mn doping Stability enhancement

Rare variants in FANCJ induce premature ovarian insufficiency in humans and mice

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Journal of Genetics and Genomics 2024年第2期51卷 252-255页

作者： Xi Yang Shuting Ren Jialin Yang Yuncheng Pan Zixue Zhou Qing Chen Yunzheng Fang Lingyue Shang Feng Zhang Xiaojin Zhang Yanhua Wu State Key Laboratory of Genetic Engineering at school of Life Sciences Human Phenome InstituteObstetrics and Gynecology HospitalFudan UniversityShanghai 200438China Obstetrics and Gynecology Hospital Institute of Reproduction and DevelopmentState Key Laboratory of Genetic Engineering at School of Life SciencesFudan UniversityShanghai 200011China Human Phenome Institute Zhangjiang Fudan International Innovation CenterFudan UniversityShanghai 201203China Obstetrics and Gynecology Hospital Institute of Reproduction and DevelopmentFudan UniversityShanghai 200011China State Key Laboratory of Genetic Engineering at school of Life Sciences Obstetrics and Gynecology HospitalFudan UniversityShanghai 200438China National Demonstration Center for Experimental Biology Education School of Life SciencesFudan UniversityShanghai 200433China

Premature ovarian insufficiency(POI)is a severe female reproductive disorder that affects 1%of women in general populations(European Society for Human Reproduction and Embryology[ESHRE]Guideline Group on POI et al.,2016).An increasing prevalence up to 3.7%has been reported in a recent meta-analysis(Golezar et al.,2019).POl can lead to infertility or subfertility,as well as a range of complex complications suffering multi-organ systems,seriously threatening women's health and reducing the life quality.By contrast,POl is a representative heterogeneous disease with multiple etiologies.While more than 70 causative POI genes have been identified,the etiology of more than half of the POI patients is still ambiguous(Jiao et al.,2018).Unreported POI causative genes,therefore,remain to be identified.

关键词： insufficiency fertility

Experimental realization of fractal fretwork metasurface for sound anomalous modulation

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Chinese Physics B 2024年第5期33卷 473-478页

作者：何佳杰于书萌江雪他得安 Department of Biomedical Engineering School of Information Science and TechnologyFudan UniversityShanghai 200433China Academy for Engineering and Technology Fudan UniversityShanghai 200433China

Natural creatures and ancient cultures are full of potential sources to provide inspiration for applied sciences.Inspired by the fractal geometry in nature and the fretwork frame in ancient culture,here we design the acoustic metasurface to realize sound anomalous modulation,which manifests itself as an incident-dependent propagation behavior:sound wave propagating in the forward direction is allowed to transmit with high efficiency while in the backward direction is obviously suppressed.We quantitatively investigate the dependences of asymmetric transmission on the propagation direction,incident angle and operating frequency by calculating sound transmittance and energy contrast.This compact fractal fretwork metasurface for acoustic anomalous modulation would promote the development of integrated acoustic devices and expand versatile applications in acoustic communication and information encryption.

关键词： acoustic metasurface fractal geometry sound anomalous modulation

Design study of charge-stripping scheme of heavy ion beams for HIAF-BRing

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Nuclear Science and Techniques 2024年第5期35卷 30-41页

作者： Jun-Jie Zhang Zhi-You Xu Jin-Quan Zhang Wen-Wen Ge Liang-Ting Sun Huan-Yu Zhao Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China school of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Charge strippers play an essential role in heavy-ion accelerators by stripping the projectile ions to higher charge states to enhance the acceleration efficiency downstream of the stripper.In the high-energy mode of the booster ring(BRing)of the high-intensity heavy-ion accelerator facility,the pre-accelerated ions from the iLinac will be stripped by a carbon foil to higher charge states and then injected into the BRing.The key parameters of the stripper and stripped ions were calculated,and the influence of stripping on the beam quality was discussed.To get high stripping efficiencies,the foil thicknesses and resultant charge state distributions for the typical ions were determined by the code ETACHA.The equilibrium thickness was obtained for the U beam,while the stripper thicknesses for the Xe and Kr beams were determined based on a compromise between the stripped charge states and the stripping efficiency.The energy loss,energy straggling,and emittance growth due to stripping have a non-negligible impact on the transport of the stripped beams and the injection of the ring.Therefore,these parameters were simulated by GEANT4.In addition,the foil’s temperature evolution,which greatly affects the foil lifetime,was simulated by ANSYS.The maximum temperature of the foil bombarded by the U and Xe beams with the nominal parameters will exceed the safe value in terms of the impact of evaporation on the foil’s lifetime.Given the foil temperature constraint,the highest tolerable beam intensity and the injected ion number into the ring were derived for different beam sizes.The results of this paper will present important reference data for the optimization design and commissioning of the beamline and injection to the BRing for the stripped ions.

关键词： High-intensity heavy-ion accelerator facility Charge stripper Energy spread Thermal analysis Emittance growth Injection turns

Space debris environment engineering model 2019:Algorithms improvement and comparison with ORDEM 3.1 and MASTER-8

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Chinese Journal of Aeronautics 2024年第5期37卷 392-409页

作者： Yuyan LIU Runqiang CHI Baojun PANG HU Diqi Wuxiong CAO Dongfang WANG school of Astronautics Harbin Institute of TechnologyHarbin 150001China College of Safety Science&Engineering Civil Aviation University of ChinaTianjin 300300China

As an essential tool for realistic description of the current or future debris environment,the Space Debris Environment Engineering Model(SDEEM)has been developed to provide support for risk assessment of spacecraft.In contrast with SDEEM2015,SDEEM2019,the latest version,extends the orbital range from the Low Earth Orbit(LEO)to Geosynchronous Orbit(GEO)for the years 1958-2050.In this paper,improved modeling algorithms used by SDEEM2019 in propagating simulation,spatial density distribution,and spacecraft flux evaluation are presented.The debris fluxes of SDEEM2019 are compared with those of three typical models,i.e.,SDEEM2015,Orbital Debris Engineering Model 3.1(ORDEM 3.1),and Meteoroid and Space Debris Terrestrial Environment Reference(MASTER-8),in terms of two assessment modes.Three orbital cases,including the Geostationary Transfer Orbit(GTO),Sun-Synchronous Orbit(SSO)and International Space Station(ISS)orbit,are selected for the spacecraft assessment mode,and the LEO region is selected for the spatial density assessment mode.The analysis indicates that compared with previous algorithms,the variable step-size orbital propagating algorithm based on semi-major axis control is more precise,the spatial density algorithm based on the second zonal harmonic of the non-spherical Earth gravity(J_(2))is more applicable,and the result of the position-centered spacecraft flux algorithm is more convergent.The comparison shows that SDEEM2019 and MASTER-8 have consistent trends due to similar modeling processes,while the differences between SDEEM2019 and ORDEM 3.1 are mainly caused by different modeling approaches for uncatalogued debris.

关键词： SDEEM2019 Space debris propagating algorithm Spatial density algorithm ORDEM 3.1 MASTER-8

Effects of iron oxide on crystallization behavior and spatial distribution of spinel in stainless steel slag

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 292-300页

作者： Zihang Yan Qing Zhao Chengzhi Han Xiaohui Mei Chengjun Liu Maofa Jiang Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education Northeastern UniversityShenyang 110819China school of Metallurgy Northeastern UniversityShenyang 110819China

Chromium plays a vital role in stainless steel due to its ability to improve the corrosion resistance of the latter.However,the re-lease of chromium from stainless steel slag(SSS)during SSS stockpiling causes detrimental environmental issues.To prevent chromium pollution,the effects of iron oxide on crystallization behavior and spatial distribution of spinel were investigated in this work.The results revealed that FeO was more conducive to the growth of spinels compared with Fe2O3 and Fe3O4.Spinels were found to be mainly distrib-uted at the top and bottom of slag.The amount of spinel phase at the bottom decreased with the increasing FeO content,while that at the top increased.The average particle size of spinel in the slag with 18wt%FeO content was 12.8μm.Meanwhile,no notable structural changes were observed with a further increase in FeO content.In other words,the spatial distribution of spinel changed when the content of iron oxide varied in the range of 8wt%to 18wt%.Finally,less spinel was found at the bottom of slag with a FeO content of 23wt%.

关键词： stainless steel slag spinel chromium waste remediation ferrous oxide

Extraction of Valuable Metals from Titanium-bearing Blast Furnace Slag by Acid Leaching

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 376-385页

作者：刘燕 CHEN Xuegui MAO Shuaidong XIAO Yadong LI Jiacong school of Metallurgy Northeastern UniversityShenyang 110819China Key Laboratory of Ecological Metallurgy of Multi-metal Intergrown Ores of Ministry of Education Shenyang 110819China

To realize the resource utilization of the valuable metals in the titanium-containing blast furnace slag,the process route of “hydrochloric acid leaching-electrolysis-carbonization and carbon dioxide capture-preparation of calcium carbonate” was proposed.In this study,the influences of process conditions on the leaching rates of calcium,magnesium,aluminum,and iron and the phases of the leaching residue were investigated for the leaching process.The experimental results show that the HCl solution could selectively leach the elements from the titanium-containing blast furnace slag.The better leaching conditions are the HCl solution concentration of 4 mol/L,the leaching time of 30 min,the ratio of liquid volume to solid gas of 10 mL/g,and the stirring paddle speed of 300 r/min.Under the conditions,the leaching rates of calcium,magnesium,aluminum,and iron can reach 85.87%,73.41%,81.35%,and 59.08%,and the leaching rate of titanium is 10.71%.The iron and the aluminum are removed from the leachate to obtain iron-aluminum water purification agents,and the magnesium is removed from the leachate to obtain magnesium hydroxide.The leaching residue phase is dominated by perovskite,followed by magnesium silicate and tricalcium aluminate,and the titaniumrich material could be obtained from the leaching residue by desiliconization.

关键词： titanium-containing blast furnace slag acid leaching valuable metals comprehensive utilization

Parametric formation control of multiple nanosatellites for cooperative observation of China Space Station

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Astrodynamics 2024年第1期8卷 77-95页

作者： Hao Zhou Bohan Jiao Zhaohui Dang Jianping Yuan school of Astronautics Northwestern Polytechnical UniversityXi’an710072China National Key Laboratory of Aerospace Flight Dynamics Northwestern Polytechnical UniversityXi’an710072China

This study proposes a parametric formation control method for the cooperative observation of the China Space Station(CSS)using multiple nanosatellites.First,a simplified geometrical model of the CSS is constructed using fundamental solids,such as the capsule body and cuboid.Second,the spacecraft formation configuration for the observation mission is characterized by a three-dimensional(3D)Lissajous curve using related design parameters under the full-coverage observation requirements of specific parts,such as the CSS connecting section and collision avoidance constraints.Third,a double-layer control law is designed for each nanosatellite,in which the upper layer is a distributed observer for recognizing the target formation configuration parameters,and the lower layer is a trajectory-tracking controller to make the nanosatellite converge to its temporary target position calculated from the upper layer’s outputs.The closed-loop control stability is proven under the condition that the communication network topology of the nanosatellite cluster contains a directed spanning tree.Finally,the control method is verified by numerical simulation,where the CSS connecting section is selected as the observation target,and ten small nanosatellites are assumed to perform the cooperative observation mission.The simulation results demonstrate that the double-layer control law is robust to single-point communication failures and suitable for the accompanying missions of large space objects with multiple nanosatellites.

关键词： China Space Station(CSS) cooperative observation parametric formation 3D Lissajous curve double-layer system

Effects of conductive agent type on lithium extraction from salt lake brine with LiFePO_(4) electrodes

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 678-687页

作者： Zhen Zhang Pan Luo Yan Zhang Yuhan Wang Li Liao Bo Yu Mingshan Wang Junchen Chen Bingshu Guo Xing Li school of New Energy and Materials Southwest Petroleum UniversityChengdu 610500China Energy Storage Research Institute Southwest Petroleum UniversityChengdu 610500China

Electrochemical lithium extraction from salt lakes is an effective strategy for obtaining lithium at a low cost.Nevertheless,the elevated Mg:Li ratio and the presence of numerous coexisting ions in salt lake brines give rise to challenges,such as prolonged lithium extraction periods,diminished lithium extraction efficiency,and considerable environmental pollution.In this work,Li FePO4(LFP)served as the electrode material for electrochemical lithium extraction.The conductive network in the LFP electrode was optimized by adjusting the type of conductive agent.This approach resulted in high lithium extraction efficiency and extended cycle life.When the single conductive agent of acetylene black(AB)or multiwalled carbon nanotubes(MWCNTs)was replaced with the mixed conductive agent of AB/MWCNTs,the average diffusion coefficient of Li+in the electrode increased from 2.35×10^(-9)or 1.77×10^(-9)to 4.21×10^(-9)cm^(2)·s^(-1).At the current density of 20 mA·g^(-1),the average lithium extraction capacity per gram of LFP electrode increased from 30.36 mg with the single conductive agent(AB)to 35.62 mg with the mixed conductive agent(AB/MWCNTs).When the mixed conductive agent was used,the capacity retention of the electrode after 30 cycles reached 82.9%,which was considerably higher than the capacity retention of 65.8%obtained when the single AB was utilized.Meanwhile,the electrode with mixed conductive agent of AB/MWCNTs provided good cycling performance.When the conductive agent content decreased or the loading capacity increased,the electrode containing the mixed conductive agent continued to show excellent electrochemical performance.Furthermore,a self-designed,highly efficient,continuous lithium extraction device was constructed.The electrode utilizing the AB/MWCNT mixed conductive agent maintained excellent adsorption capacity and cycling performance in this device.This work provides a new perspective for the electrochemical extraction of lithium using LFP electrodes.

关键词： salt lake brine lithium extraction electrochemical lithium extraction conductive agent extraction efficiency adsorption capacity

Singular optical propagation properties of two types of one-dimensional anti-PT-symmetric periodic ring optical waveguide networks

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Chinese Physics B 2024年第3期33卷 355-362页

作者：樊阳龙杨湘波练华达陈润楷朱蓬勃邓冬梅刘宏展韦中超 Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices School of Information and Optoelectronic Science and EngineeringSouth China Normal UniversityGuangzhou 510006China

Two types of one-dimensional(1D)anti-PT-symmetric periodic ring optical waveguide networks,consisting of gain and loss materials,are constructed.The singular optical propagation properties of these networks are investigated.The results show that the system composed of gain materials exhibits characteristics of ultra-strong transmission and bidirectional reflection.Conversely,the system composed of loss materials demonstrates equal transmittance and reflectance at some frequencies.In both the systems,a new type of total reflection phenomenon is observed.When the imaginary part of the refractive indices of waveguide segments is smaller than 10-5,the system shows bidirectional transparency with the transmittance tending to be 1 and reflectivity to be smaller than 10-8 at some bands.When the refractive indices of the waveguide segments are real,the system will be bidirectional transparent at the full band.These findings may deepen the understanding of anti-PT-symmetric optical systems and optical waveguide networks,and possess potential applications in efficient optical energy storage,ultra-sensitive optical filters,ultra-sensitive all-optical switches,integrated optical chips,stealth physics,and so on.

关键词： anti-PT-symmetric waveguide networks bidirectional transparent