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A LEVEL SET METHOD FOR SIMULATION OF RISING BUBBLE

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Journal of Hydrodynamics 2004年第4期16卷 379-385页

作者： huangjun-tao zhanghui-sheng DepartmentofMechanicsandEngineeringSciences FudanUniversityShanghai200433China

A level set method, the TVD scheme of second-order upwind procedure coupledwith flux-limiter, and SIMPLE algorithm were incorporated to simulate the flow and interfacialmotion of immiscible two-fluids with large density ratio and viscosity ratios, large topologydistortion and surface tension. As a numerical example axi-symmetric rising bubbles wereinvestigated. It is found that the method is numerically stable and has good convergence propertyand the results are in good agreement with other works.

关键词： level set method high-resolution scheme SIMPLE algorithm rising bubble

Assessment of the induced radioactivity in the treatment room of the heavy-ion medical machine in Wuwei using PHITS

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Nuclear Science and Techniques 2023年第2期34卷 153-166页

作者： Ying Luo sheng‑Cong huang hui zhang Hai‑jun Mao Qiang Li Zhong‑Ying Dai Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Science Lanzhou 730000China Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine Lanzhou 730000China Lanzhou University Lanzhou 730000China

Carbon-ion radiotherapy(CIRT)offers unique physical and biological advantages over photon ***,some materials and devices in the CIRT treatment room become radioactive under bombardment by therapeutic carbon-ion beams due to nuclear reactions,thereby leading to possible radiation hazards to medical staff and additional and unwanted doses to *** study assessed the level of induced radioactivity in the treatment room of the Heavy-Ion Medical Machine(HIMM)in *** Carlo simulations using PHITS were performed for a conservative case under the conditions of maximum beam energy and intensity provided by the HIMM *** geometry and configuration of Treatment Room 2 of the HIMM facility in Wuwei were *** evaluated the activation of air,the phantom,and the components of the beamline,such as the primary collimator(PC),ridge filter(RF),and multileaf collimator(MLC).For air activation,we calculated the medical staff immersion external exposure and inhalation internal exposure caused by the corresponding *** phantom activation,we estimated the additional dose to the patient’s family members owing to secondary photons after *** addition,the exemption or non-exemption of the component material activation was *** results showed that external radiation caused by air activation was the main source of the annual effective dose at approximately 0.5 mSv/*** induced radioactivity exposure to family members of a patient after CIRT was approximately 40μSv,sufficiently lower than the public dose limit of 1 mSv/*** induced radioactivity of the PC,RF,and MLC was all above the exempt levels after the devices were retired,whereas the induced radioactivity of the RS and compensator could reach the exempt levels after one patient *** study indicated that medical staff engaged in CIRT should stay away from the high-dose-rate area of induced radioactivity along the beam direction,shorten the residence time in

关键词： activation approximate thereby

Monte Carlo study of the neutron ambient dose equivalent at the heavy ion medical machine in Wuwei

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Nuclear Science and Techniques 2022年第9期33卷 111-125页

作者： sheng-Cong huang hui zhang Kai Bai Ying Luo Hai-jun Mao Zhong-Ying Dai University of Chinese Academy of Sciences Beijing 100049China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China

The use of carbon-ion radiotherapy(CIRT)is gradually *** to the generation of high-energy secondary neutrons during CIRT,its use presents new challenges in radiation ***,secondary neutron dose distributions must be explored and evaluated under clinical scenarios based on different treatment ***,neutron dose and energy spectrum measurements are often *** can be primarily attributed to the inherent limitations of most neutron detectors,such as their unsuitability for spectral measurements and inaccurate responses to neutrons with energies above 20 *** calculation methods based on probabilistic statistical theory are fast and convenient for neutron dose *** this study,external secondary neutron doses at the heavy ion medical machine in Wuwei,which is equipped with a passive beam delivery system,were calculated using the Monte Carlo *** dependence of neutron doses on various treatment parameters(incident carbon-ion beam energy,spatial location,field size,and spread-out Bragg peak(SOBP)width)was ***,the feasibility of applying an analytical model to predict the ambient dose equivalent was *** the combination involving an energy of 400 MeV=u and SOBP width of 6 cm,the ambient dose equivalent per therapeutic dose(H=D)at the isocenter was 79.87 mSv=Gy:The H=D value decreased rapidly with increasing spatial distance and slightly with increasing aperture size and SOBP *** H=D values derived from the Monte Carlo simulations were in good agreement with the results reported in the *** analytical model could be used to quickly predict the H=D value along the incidence direction of the beam with an error of less than 20%.Thus,our study contributes to the understanding of the relationship between neutron radiation and treatment configuration parameters,which establishes a basis for predicting non-therapeutic radiation doses in CIRT.

关键词： Carbon-ion radiotherapy Passive beam delivery Secondary neutrons Monte Carlo method

Fractionation characteristics of magnesium isotope in the ancient weathering crust

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Petroleum Science 2023年第3期20卷 1446-1457页

作者： Jia-Qi Yang jun-tao zhang Zhi-Liang He Ni-Na Luo Xiao-hui Jjin tao zhang Ning Gu Kang-jun huang jian Gao School of Energy Resources China University of GeosciencesBeijing100083China SINOPEC Exploration and Production Research Institute Beijing100083China China Petrochemical Corporation Ltd. Beijing100728China Key Laboratory of Deep Geology and Resources SINOPECBejing102206China Chongqing Gas Field of Petro China Southwest Oil and Gas Field Company Chongqing400021China Shaanxi Key Laboretory of Early Life and Environments Department of GeologyNorthwest UniversityXi'anShaanxi710069China

Weathering has always been a concerned around the world,as the first and most important step in the global cycle of elements,which leads to the fractionation of isotopes on the scale of geological *** Middle Ordovician Majiagou Formation in Daniudi area of the Ordos Basin had experienced weathering for>130 *** thin section observation,major and trace element analysis,carbon,oxygen,and magnesium isotopes composition analysis,the dolomitization modes and weathering of ancient dolo-mite in Daniudi area were analyzed in *** results showed that the Sabkha and brine-reflux dolomitization modes had developed,and the Mg isotopes in different layers of the karst crust were fractionated by various *** vertical vadose zone was affected by weathering,the Mg isotope of dolomite(δ^(26)Mgdol)showed a downward decreasing trend;the horizontal underflow zone was controlled by diagenesis and formation fluid,δ^(26)Mgdol showed a vertical invariance and negative;the main reason for Mg isotope fractionation in the deep slow-flow zone was the brine-reflux dolomitization mode during early burial period,which showed a vertical downward ***,the Mg isotope characteristic data of the ancient weathering crust were provided and the process of Mg isotope frac-tionationinthekarstcrust was explained.

关键词： Magnesium isotope Dolomitization mode Weathering Ancient weathering crust Ordos Basin

Enhanced sulfide chemisorption by conductive AI-doped ZnO decorated carbon nanoflakes for advanced Li-S batteries

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Nano Research 2018年第1期11卷 477-489页

作者： Yangbo Kong Jianmin Luo Chengbin Jin Huadong Yuan Ouwei sheng Liyuan zhang Cong Fang Wenkui zhang hui huang Yang Xia Chu Liang jun zhang Yongping Gan Xinyong tao College of Materials Science and Engineering Zhejiang University of Technology Hangzhou 310014 China

Lithium-sulfur batteries have attracted significant attention recently due to their high theoretical capacity, energy density and cost effectiveness. However, sulfur cathodes suffer from issues such as shuttle effects, uncontrollable deposition of lithium sulfides species, and volume expansion of sulfur, which result in rapid capacity fading and low Coulombic efficiency. In recent years, metal-oxide nanostructures have been widely used in Li-S batteries, owing to their effective inhibition of the shuttle effect and controlled deposition of lithium sulfide. However, the nonconductive metal-oxides used in Li-S batteries suffer from extra diffusion process, which slows down the electrochemical reaction kinetics. Herein, we report the synthesis of carbon nanoflakes decorated with conductive aluminium-doped zinc oxide （AZO@C） nanoparticles, through a facile biotem- plating method using kapok fibers as both the template and carbon source. A sulfur cathode based on the AZO@C nanocomposites shows better electrochemical performance than those of cathodes based on ZnO and A1203 with poor conductivity, with a stable capacity of 927 mAh.g-1 at 0.1C （1C = 1,675 mA.g-1） after 100 cycles. A reversible capacity of 544 mAh.g-1 after 300 cycles was obtained even after increasing the current density to 0.5C, with a 0.039% capacity decay per cycle under a sulfur loading of 3.3 mg-cm-2. Moreover, a capacity of 466 mAh.g-1 after 100 cycles at 0.5C could still be obtained when the sulfur loading was increased to 6.96 ***-2. The excellent electrochemical performance of the AZO@C/S composite can be attributed to its high conductivity of the polar AZO host, which suppresses the shuttle effect while simultaneously improving the redox kinetics in the reciprocal transformation of lithium sulfide species.

关键词： lithium-sulfur battery aluminium-doped zincoxide conductive nanostructure biotemplate carbon nanoflakes

Three New Silver Alkylenediphosphonates with Pillar-like Open-frameworks

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Chinese Journal of Structural Chemistry 2005年第11期24卷 1231-1241页

作者： FU Rui-Biao HU sheng-Min zhang hui-Shuang WANG Long-sheng LI Ya-Min huang Xi-He WU Xin-tao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Science Fuzhou Fujian 350002 China

Three new silver alkylenediphosphonates, [Ag2（HO3PCH2CH2CH2CH2PO3H）] 1, [Ag4（O3PCH2CH2CH2CH2PO3）] 2 and [Ag4（O3PCH2CH2CH2PO3（H2O）] 3, have been hydrotherreally synthesized and characterized by X-ray single-crystal and powder diffraction, elemental analyses, IR and thermogravimetric analyses （TGA）. The structures of these compounds are all threedimensional pillar-like open-frameworks with 18-membered [Ag2O4P4C8] channels for compound 1 and 2, and 16-member [Ag2O4P4C6] channels for compound 3. Both 2 and 3 contain interesting twodimensional Ag（Ⅰ） networks based on Ag...Ag interactions. 1,4-Butylene- and 1,3-propylene diphosphonate groups of 2 and 3 bond the first and second maximum metal atoms among metal organodiphosphonates with linking sixteen and fifteen silver（Ⅰ） atoms, respectively. In addition, the coordinated water molecules of 3 can be reversibly removed and recovered.

关键词： hydrothermal syntheses silver diphosphonate pillar-like single crystal

A critical review on composite solid electrolytes for lithium batteries:Design strategies and interface engineering

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Journal of Energy Chemistry 2023年第9期84卷 189-209页

作者： Tianqi Yang Cheng Wang Wenkui zhang Yang Xia hui huang Yongping Gan Xinping He Xinhui Xia Xinyong tao jun zhang College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014ZhejiangChina

The rapid development of new energy vehicles and 5G communication technologies has led to higher demands for the safety,energy density,and cycle performance of lithium-ion batteries as power ***,the currently used liquid carbonate compounds in commercial lithium-ion battery electrolytes pose potential safety hazards such as leakage,swelling,corrosion,and *** electrolytes can be used to mitigate these risks and create a safer lithium ***,high-energy density can be achieved by using solid electrolytes along with high-voltage cathode and metal lithium *** types of solid electrolytes are generally used:inorganic solid electrolytes and polymer solid *** solid electrolytes have high ionic conductivity,electrochemical stability window,and mechanical strength,but suffer from large solid/solid contact resistance between the electrode and *** solid electrolytes have good flexibility,processability,and contact interface properties,but low room temperature ionic conductivity,necessitating operation at elevated *** solid electrolytes(CSEs) are a promising alternative because they offer light weight and flexibility,like polymers,as well as the strength and stability of inorganic *** paper presents a comprehensive review of recent advances in CSEs to help researchers optimize CSE composition and interactions for practical *** covers the development history of solid-state electrolytes,CSE properties with respect to nanofillers,morphology,and polymer types,and also discusses the lithium-ion transport mechanism of the composite electrolyte,and the methods of engineering interfaces with the positive and negative ***,the paper aims to provide an outlook on the potential applications of CSEs in solid-state lithium batteries,and to inspire further research aimed at the development of more systematic optimization strategies for CSEs.

关键词： Inorganic solid electrolytes Polymer solid electrolytes Composite solid electrolytes Interface engineering

Synthesis and Crystal Structure of a Novel Heptanuclear Ruthenium- and Sodium-containing Polyoxomolybdate [{Na(H_2O)_3}_2{Ru(dmso)_3}_2(MoO_4)_3]·_3H_2O

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Chinese Journal of Structural Chemistry 2006年第7期25卷 783-788页

作者： huang Xi-He XIANG sheng-Chang FU Rui-Biao sheng Tian-Lu zhang Jian-jun LI Ya-Min WANG Long-sheng WU Xin-tao State Key Laboratory of Structural Chemistry Fujian Institute of Research on theStructure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

The title compound, [{Na（H2O）3}2lRu（dmso）3}2（MoO4）3]·3H2O, has been obtained by the reaction of Na2MoO4·2H2O with cis-Ru（dmso）4Cl2 in aqueous solution. Its crystal structure was determined by single-crystal X-ray diffraction method. The crystal crystallizes in the triclinic system, space group PI^- with a = 12.3333（3）, b = 12.6289（3）, c = 32.0284（14） A, α = 79.873（7）, β= 87.549（9）, γ = 64.500（4）°, V = 4429.5（2） A^3, Z = 4, Mr = 1358.85, Dc = 2.038 g/cm^3, F（000） = 2696 and μ = 1.874 mm^-1. The compound contains a novel pentanuclear triangle bipyramidal core, [{ Ru（dmso）3 } 2（MoO4）3]^2-, which consists of two { Ru（dmso）3 } ^2＋ fragments and three {μ2-MoO4}^2- units. Furthermore, the dmso ligands bridge the pentanuclear [Ru2Mo3] core and two [Na（H2O）3]^＋ fragments together, forming a neutral heptanuclear ruthenium- and sodiumcontaining polyoxomolybdate.

关键词： synthesis crystal structure ruthenium sodium polyoxomolybdate

Effects of long-term grazing exclusion on vegetation structure,soil water holding capacity,carbon and nitrogen sequestration capacity in an alpine meadow on the Tibetan Plateau

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Journal of Mountain Science 2023年第3期20卷 779-791页

作者： YANG Yong-sheng zhang Fa-wei XIE Xian-rong WANG jun-bang LI Ying-nian huang Xiao-tao LI hui-ting ZHOU Hua-kun Key Laboratory of Adaptation and Evolution of Plateau Biota and Key Laboratory of Restoration Ecology in Cold Region of Qinghai Province Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008China Qinghai Haibei National Field Research Station of Alpine Grassland Ecosystem Xining 810008China Xi Ning Municipal Beishan Forestry Farm Xining 810003China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

Grazing exclusion is one of the primary management practices used to restore degraded grasslands on the Tibetan ***,to date,the effects of long-term grazing exclusion measures on the process of restoring degraded alpine meadows have not been *** this study,moderately degraded plots,in which the vegetation coverage was approximately 65%and the dominant plant species was Potentilla anserina L,with grazing exclusion for 2 to 23 years,were selected in alpine meadows of Haibei in Qinghai-Tibet *** coverage,plant height,biomass,soil bulk density,saturated water content,soil organic carbon(SOC)and total nitrogen(TN)were *** results were as follows:(1)With aboveground biomass and total saturated water content at 0-40 cm depth,the average SOC and TN contents in moderately degraded alpine meadows increased as a power function,and the plant height increased as a log function.(2)The average soil bulk density at 0-40 cm depth first decreased and then increased with increasing grazing exclusion duration,and the minimum value of 0.90 g·cm^(-3) was reached at 15.23 *** plant coverage,total belowground biomass at 0-40 cm depth,total aboveground and belowground biomass first increased and then decreased,their maximum values(80.49%,2452.92g·m^(-2),2891.06 g·m^(-2))were reached at 9.41,9.46 and 10.25 years,***-term grazing exclusion is apparently harmful for the sustainable restoration of degraded alpine *** optimal duration of grazing exclusion for the restoration of moderately degraded alpine meadows was 10 *** research suggests that moderate disturbance should be allowed in moderately degraded alpine meadows after 10years of grazing exclusion.

关键词： Long-term grazing exclusion Soil water holdingcapacity Soilcarbonand nitrogen sequestration Biomass Alpine meadow