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Fluid Dynamics & Materials Processing 2024年第10期20卷 2183-2204页

作者： Zhenhua jiang Xi Deng Xin zhang Chao Yan Feng Xiao Jian Yu College of Aeronautics science and Engineering Beijing University of Aeronautics and AstronauticsBeijing100191China department of Chemical Engineering Imperial College LondonLondonSW72AZUK department of Engineering University of CambridgeCambridgeCB21PZUK department of Mechanical Engineering Tokyo Institute of TechnologyTokyo152-8550Japan

Shock waves,characterized by abrupt changes in pressure,temperature,and density,play a significant role in various materials science processes involving *** high-energy phenomena are utilized across multiple fields and applications to achieve unique material properties and facilitate advanced manufacturing *** simulations of these phenomena require numerical schemes that can represent shock waves without spurious oscillations and simultaneously capture acoustic waves for a wide range of wavelength *** work suggests a high-order discontinuous Galerkin(DG)method with a finite volume(FV)subcell limiting strategies to achieve better subcell resolution and lower numerical diffusion *** switching to the FV discretization on an embedded sub-cell grid,the method displays advantages with respect to both DG accuracy and FV shock-capturing *** FV scheme utilizes a class of high-fidelity schemes that are built upon the boundary variation diminishing(BVD)reconstruction *** method is therefore able to resolve discontinuities and multi-scale structures on the subcell level,while preserving the favorable properties of the high-order DG *** have tested the present DG method up to the 6th-order accuracy for both smooth and discontinuous noise problems.

关键词： Discontinuous Galerkin finite volume subcell limiting shock associated noise computational aeroacoustics

Relative position determination of a lunar rover using high-accuracy multi-frequency same-beam VLBI

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science china.Physics,Mechanics & Astronomy) 2010年第3期53卷 571-578页

作者： LIU QingHui1, CHEN Ming1, XIONG WeiMing2. QIAN ZhiHan1, LI JinLing1, HAO WangHong1,4, WANG GuangLi1, ZHENG WeiMin1, GUAN Di3. ZHU RenJie1, WANG WeiHua1, zhang XiuZhong1, jiang DongRong1, SHU FengChun1, PING JinSong1 & HONG XiaoYu11 Shanghai Astronomical Observatory, Chinese Academy of {2.s, Shanghai 2.003., china.2.Center for Space {2. and Applied Research, Chinese Academy of {2.s, beijing 100190, china.3.Lunar Explorer Engineering General department, Chinese Academy of {2.s, beijing 100012. china.4 beijing Institute of Tracking and Telecommunications Technology, beijing 100094, china 1. Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China2. Center for Space Science and Applied Research Chinese Academy of Sciences Beijing 100190 China4. Beijing Institute of Tracking and Telecommunications Technology Beijing 100094 China3. Lunar Explorer Engineering General Department Chinese Academy of Sciences Beijing 100012 China

Multi-frequency same-beam VLBI means that two explorers with a small separation angle are simultaneously observed with the main beam of receiving antennas. In the same-beam VLBI, the differential phase delay between two explorers and two receiving telescopes can be obtained with a small error of several picoseconds. The differential phase delay, as the observable of the same-beam VLBI, gives the separation angular information of the two explorers in the celestial sphere. The two-dimensional relative position on the plane-of-sky can thus be precisely determined with an error of less than 1 m for a distance of 3.8×105 km far away from the earth, by using the differential phase delay obtained with the four Chinese VLBI stations. The relative position of a lunar rover on the lunar surface can be determined with an error of 10 m by using the differential phase delay data and the range data for the lander when the lunar topography near the rover and the lander can be determined with an error of 10 m.

关键词： same-beam VLBI differential phase delay relative position determination lunar rover

Multiuser detection algorithm based on belief propagation in multiple-input multiple-output systems

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science in china.Series F) 2004年第3期47卷 384-393页

作者： jiang Wei XIANG Haige department of Electronics, Peking University, {2. 100871, {3. 1. department of Electronics Peking University 100871 Beijing China

In MIMO (multiple-input, multiple-output) systems, signals from differenttransmitting antennas interfere at each receiving antenna and multiuser detection (MUD)algorithms may be adopted to improve the system performance. This paper proposes anovel multiuser detection algorithm in MIMO systems based on the idea of 'beliefpropagation' which has achieved great accomplishment in decoding of low-densityparity-check codes. The proposed algorithm has a low computation complexityproportional to the square of transmitting/receiving antenna number. Simulation resultsshow that under low signal-to-noise ratio (SNR) circumstances, the proposed algorithmoutperforms the traditional linear minimum mean square error (MMSE) detector while itencounters a 'floor' of bit error rate under high SNR circumstances. So the proposedalgorithm is applicable to MIMO systems with channel coding and decoding. Although inthis paper the proposed algorithm is derived in MIMO systems, obviously it can be appliedto ordinary code-division multiple access (CDMA) systems.

关键词： multiple-input multiple-output belief propagation multiuser detection

Evaluation of laboratory and environmental exposure systems for protein modification upon gas pollutants and environmental factors

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Journal of Environmental sciences 2024年第9期143卷 213-223页

作者： Zhiwei Pan ShiyiWu Qiaoze Zhu Fobang Liu Yongjian Liang Chenglei Pei Haoyu jiang Yingyi zhang Senchao Lai The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationSchool of Environment and EnergySouth China University of TechnologyGuangzhou 510006China department of Environmental science and Engineering Xi’an Jiaotong UniversityXi’an 710049China Guangzhou Sub-branch of Guangdong Ecological and Environmental Monitoring Center Guangzhou 510006China State Key Laboratory of Organic Geochemistry Guangdong Key Laboratory of Environmental Protection and Resources Utilizationand Joint Laboratory of the Guangdong-Hong Kong-Macao Greater Bay Area for the EnvironmentGuangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China school of Marine sciences Sun Yat-sen UniversityZhuhai 519082China

Chemical modifications of proteins induced by ambient ozone(O_(3.)and nitrogen oxides(NOx)are of public health concerns due to their potential to trigger respiratory *** laboratory and environmental exposure systems have been widely used to investigate their relevant mechanism in the *** bovine serum albumin(BSA)as a model protein,we evaluated the two systems and aimed to reduce the uncertainties of both the reactants and products in the corresponding kinetic *** the laboratory simulation system,the generated gaseous pollutants showed negligible *** layers of BSA were coated on the flow tube with protein extraction recovery of 87.4%.For environmental exposure experiment,quartz fiber filter was selected as the upper filter with low gaseous O_(3.(8.0%)and NO_(2.(1.7%)losses,and cellulose acetate filter was appropriate for the lower filter with protein extraction efficiency of 95.2..The protein degradation process was observed without the exposure to atmospheric oxidants and contributed to the loss of protein monomer mass fractions,while environmental factors(e.g.,molecular oxygen and ultraviolet)may cause greater protein monomer *** on the evaluation,the study exemplarily applied the two systems to protein modification and both showed that O_(3. promotes the protein oligomerization and nitration,while increased temperature can accelerate the oligomerization and increased relative humidity can inhibit the nitration in the environmental exposure *** developed laboratory and environmental systems are suitable for studying protein modifications formed under different atmospheric conditions.A combination of the two will further reveal the actual mechanism of protein modifications.

关键词： Protein modification Laboratory simulation Environmental exposure Oligomerization Nitration

Tunning the bandgap of MnO_(2.homojunction by building active high-index facet to achieve rapid electron transfer for enhanced photocatalytic sterilization

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Journal of Materials science & Technology 2024年第1期168卷 265-275页

作者： Tao zhang Bo Li Chaofeng Wang Shuilin Wu Shengli Zhu Hui jiang Yufeng Zheng Zhaoyang Li Zhenduo Cui Yu zhang Paul K Chu Xiangmei Liu Biomedical Materials Engineering Research Center Hubei Key Laboratory of Polymer MaterialsMinistry-of-Education Key Laboratory for the Green Preparation and Application of Functional MaterialsSchool of Materials Science and Engineering Hubei UniversityWuhan 430062China school of Health science&Biomedical Engineering Hebei University of TechnologyTianjin 300401China school of Materials science&Engineering Peking UniversityBeijing 100871China school of Materials science&Engineering the Key Laboratory of Advanced Ceramics and Machining Technology by the Ministry of Education of ChinaTianjin UniversityTianjin 300072China department of Orthopedics Guangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhou 510080China department of Physics Department of Materials Science and Engineering and Department of Biomedical EngineeringCity University of Hong KongHong Kong 999077China

Photocatalysis has been a research hotspot in recent years,and the design and modification of photocat-alysts have been the key *** methods for designing photocatalysts,including constructing heterojunctions and homojunctions,have been developed on the basis of *** this study,two homojunctions of manganese dioxide(MnO_(2.),including a high-index crystal plane homojunction and a general homojunction,are prepared using a stepwise hydrothermal *** a capping agent,the high-index crystal surface of the MnO_(2.is *** is found that the electron transport efficiency be-tween the two components of the homojunction with high-index planes is higher and the adsorption capacity of the oxygen is stronger,which leads to higher photocatalytic *** addition,the newly designed high-index homojunction is used for the treatment of bacterial infections,and it kills Staphy-lococcus aureus(***)and Escherichia coli(***)at rates of 99.95%±0.04%and 99.3.%±0.2.%,*** also has excellent therapeutic effects on mouse wounds,which implies superb practical application *** work provides a new strategy for the improved design of homojunctions and the application of photocatalytic materials.

关键词： Photocatalysis Homojunction Bandgap High-index facet Antibacterial

Thermodynamic modeling of the La-Mg-Y system and Mg-based alloys database

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Rare Metals 2006年第5期25卷 492-500页

作者： DU Zhenmin GUO Cuiping LI Changrong zhang Weijing department of Materials science and Engineering University of Science and Technology Beijing Beijing 100083 China

As an example of the La-Mg-Y system, the method how to set up the themaodynamic model of individual phases was introduced in the process of thermodynamic optimization. The solution phases （liquid, body-centered cubic, face-centered cubic, hexagonal close-packed and double hexagonal close-packed） were modeled with the Redlich-Kister equation. The compound energy model has been used to describe the thermodynamic functions of the intermetallic compounds in the La-Mg-Y systems. The compounds Mg2., Mg2.Y5, Mg12.a, Mg17La2. Mg41Las, Mg3.a and Mg2.a in the La-Mg-Y system were treated as the formulae （Mg,Y）2.La,Mg,Y）, Mg2.（La,Mg,Y）4Y, Mg12.La, Y）, Mg17（La,Y）2. Mg41（La,Y）5, Mg3.La,Mg,Y） and Mg2.La, Y）, respectively. A model （La, Mg,Y）0.5（La,Mg,Y）0.5 was applied to describe the compound MgM formed by MgLa and MgY in order to cope with the order-disorder transition between body-centered cubic solution （A2. and MgM with CsCl-type structure （B2. in the La-Mg-Y system. The Gibbs energies of individual phases were optimized in the La-Mg, La-Y and La-Mg-Y systems by CALPHAD technique. The projection of the liquidus surfaces for the La-Mg-Y system was predicted. The Mg-based alloys database including 3. binary and 15 ternary systems formed by Mg, Al, Cu, Ni, Mn, Zn and rare earth elements was set up in SGTE standard.

关键词： La-Mg-Y system thermodynamic modeling CALPHAD technique order-disorder transition Mg-based alloys database

The numbers of periodic orbits hidden at fixed points of 2.dimensional holomorphic mappings

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science china.Mathematics 2010年第3期53卷 863-886页

作者： zhang GuangYuan department of Mathematical {2.s, Tsinghua University, {3. 100084, china 1. department of Mathematical sciences Tsinghua University Beijing 100084 China

Let △n be the ball |x| < 1 in the complex vector space C n , let f :△n→ C n be a holomorphic mapping and let M be a positive integer. Assume that the origin 0 = (0, . . . , 0) is an isolated fixed point of both f a... 详细信息

Let △n be the ball |x| 2. For a 2.× 2.matrix A that is arbitrarily given, the goal of this paper is to give a necessary and sufficient condition for A, such that O M (f, 0)≥2.for all holomorphic mappings f :△2.→ C 2.such that f(0) = 0, Df(0) = A and that the origin 0 is an isolated fixed point of f M .

关键词： complex dynamical systems periodic points fixed point indices

Large-Scale Carbon Dioxide Storage in Salt Caverns:Evaluation of Operation,Safety,and Potential in china

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Engineering 2024年第9期40卷 226-246页

作者： Wei Liu Xiong zhang Jifang Wan Chunhe Yang Liangliang jiang zhangxin Chen Maria Jose Jurado Xilin Shi Deyi jiang Wendong Ji Qihang Li State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044China china.Energy Digital Technology Group Co.Ltd. Beijing 100044China Institute of Rock and Soil Mechanics Chinese Academy of SciencesWuhan 430064China department of Chemical and Petroleum Engineering University of CalgaryCalgaryAB T2N 1N4Canada Eastern Institute of Technology Ningbo 315200China Geosciences Barcelona CSIC Spanish National Research CouncilBarcelona 08028Spain

Underground salt cavern CO_(2. storage(SCCS)offers the dual benefits of enabling extensive CO_(2. storage and facilitating the utilization of CO_(2. resources while contributing the regulation of the carbon *** economic and operational advantages over traditional carbon capture,utilization,and storage(CCUS)projects make SCCS a more cost-effective and flexible *** the widespread use of salt caverns for storing various substances,differences exist between SCCS and traditional salt cavern energy storage in terms of gas-tightness,carbon injection,brine extraction control,long-term carbon storage stability,and site selection *** distinctions stem from the unique phase change characteristics of CO_(2. and the application scenarios of ***,targeted and forward-looking scientific research on SCCS is *** paper introduces the implementation principles and application scenarios of SCCS,emphasizing its connections with carbon emissions,carbon utilization,and renewable energy peak *** delves into the operational characteristics and economic advantages of SCCS compared with other CCUS methods,and addresses associated scientific *** this paper,we establish a pressure equation for carbon injection and brine extraction,that considers the phase change characteristics of CO_(2.,and we analyze the pressure during carbon *** comparing the viscosities of CO_(2. and other gases,SCCS’s excellent sealing performance is *** on this,we develop a long-term stability evaluation model and associated indices,which analyze the impact of the injection speed and minimum operating pressure on *** countermeasures to ensure stability are *** selection criteria for SCCS are established,preliminary salt mine sites suitable for SCCS are identified in china.and an initial estimate of achievable carbon storage scale in china.is made at over 51.8-77.7 million tons,utilizing only 2.%-3.%volume

关键词： Carbon-neutrality Salt cavern Large-scale CO_(2.storage Injection and withdrawal Stability analysis

Spatially discontinuous ionization phenomenon in inhomogeneous soil

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science china.Technological sciences) 2010年第4期53卷 918-921页

作者： zhang BaoPing,HE JinLiang & ZENG Rong State Key Lab of Power systems,{2. of Electrical Engineering,Tsinghua University,{3. 100084,china 1. State Key Lab of Power systems Department of Electrical Engineering Tsinghua University Beijing 100084 China

By using X-ray film imaging technology,a phenomenon of discontinuous ionization was observed in the inhomogeneous soil around the grounding electrode on which a surge voltage was applied.A simplified two-phase solid-gas model was built to study the electric field distribution in the soil to explain the discontinuous ionization *** showed the differences of the dielectric properties,the shapes and sizes of soil particles can cause discontinuous ionization in the soil.

关键词： discontinuous ionization inhomogeneous soil X-ray film porous medium electric field distribution

Sustainable development of unconventional resources: Analysis of the transient linear flow oriented straight-line analysis technique

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Energy Reviews 2024年第1期3卷 49-75页

作者： Dan Xue Liangliang jiang Zixiang Wei Maojie Chai jiang Liu Peng Deng Fuhe Lin Jian Li Jiansheng {2. {2.xing Chen department of Chemical and Petroleum Engineering University of CalgaryCalgaryAlbertaCanada Guangdong University of Petrochemical and Technology MaomingChina school of Mathematics and Data science Shaanxi University of Science and TechnologyXi'anChina department of Energy and Power Engineering Tsinghua UniversityBeijingChina Eastern Institute for Advanced Study NingboChina china.University of Petroleum(beijing) BeijingChina

On the backdrop of dwindling conventional reserves,unconventional reservoirs have emerged as a pivotal chapter in resource *** their challenges,such as low permeability,complex fluid storage,and flow mechanisms,hydraulic fracturing technology has underpinned the development of unconventional ***,this has brought about a shift in the sequence of flow regimes,e.g.,the transient radial flow regime has been largely shortened by the lengthy transient linear flow regime due to the low permeability of unconventional ***,straight-line analysis(SLA),the simplest technique in rate transient analysis(RTA),is a fundamental and potent tool for swiftly extracting reservoir and hydraulic fracture information,estimating oil and gas reserves,and furnishing crucial initial data for subsequent historical matching ***,there is currently a dearth of review papers pertaining to a necessary guide of applying SLA in various transient linear flow(TLF)regimes and different unconventional ***,this paper commences by elucidating the classification of TLF regimes,commonly used methods for recognizing flow regimes,and the diverse SLA methods used for different TLF ***,it delves into a discussion of different modification techniques for variable rate/flowing pressure,gas phase,complex reservoir characteristics in unconventional reservoirs,and dynamic drainage area concepts ***,the application of SLA in specific domains,namely core analysis and the flowback period,is *** culminates by surveying the advancements through an integration of novel technologies to enhance estimation *** paper also highlights certain drawbacks of current SLA technology and proposes new research ***,this paper would serve as an indispensable resource,offering foundational knowledge for the application of SLA in TLF to promote the production of global unconventional resources in a c

关键词： Unconventional reservoirs Straight-line analysis(SLA) Transient linear flow(TLF) Oil/gas reserves Hydraulic fracture information