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Quantum dynamics study for reaction of h.2 + OD→h.+ h.D

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Ch.nese Science Bulletin 1997年第2期42卷 116-120页

作者： zhang Yici, zhang Yanbing, zhang Desh.ngzhang Qinggang, dong h. zhang and Joh. Z. h. zhang1. Department of Ph.sics, Sh.ndong Teach.rs University, Jinan 250014, Ch.na 2. Department of Ch.mistry, New York Uni versity, New York 10003, USA Department of Ph.sics Shandong Teachers University Jinan 250014 China

TIME-dependent （TD） quantum wave packet th.ory, with.a relatively small amount of computational effort, h.s been widely used in quantum dynamics calculation of atom and molecule reaction scattering. Many computational scaling advantages of th. TD meth.d can be found apparently in polyatomic system. In th.s note, by using th. TD quantum wave packet meth.d with.th. potential-averaged 5D model （PA5D）, we give th. calculated results of reaction probabilities, cross sections and rate constants for th. h.sub>2 + OD reaction. Th. energyprojection meth.d is used to transform th. TD wave function into th. TI (energy-indepen-

关键词： propagation probability cross section rate constant.

Differential Cross Sections for th. h.D2O→h.＋OD Reaction： a Full Dimensional State-to-State Quantum Dynamics Study

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Ch.nese Journal of Ch.mical Ph.sics 2017年第1期30卷 16-24,I0001页

作者： Zh.-qiang Zh.o Sh. Liu dong h. zhang State Key Laboratory of Molecular Reaction Dynamics and Center for Th.oretical Computational Ch.mistry Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 China University of Ch.nese Academy of Sciences Beijing 100049 China

Th. time-dependent wave-packet meth.d was employed to calculate th. first full-dimensional state-to-state differential cross sections （DCS） for th. title reaction with.D2O in th. ground and th. first symmetric （100） and asymmetric stretch.ng （001） excited states. Th. calculated DCSs for th.se th.ee initial states are strongly backward peaked at low collision energies. With.th. increase of collision energy, th.se DCSs become increasingly broader with.th. peak position sh.fting gradually to a smaller angle, consistent with.th. fact th.t th. title reaction is a direct reaction via an abstraction mech.nism. It is found th.t th. （100） and （001） states not only h.ve rough.y th. same integral cross sections, but also h.ve essentially identical DCS, wh.ch.are very close to th.t for th. ground state at th. same total energy of reaction. Th. reaction produces a small fraction of OD in th. v=1 state, with.th. population close to th. relative reactivity between th. ground and vibrationally excited states, th.refore confirming th. experimental result of Zare et al. and th. local mode picture [J. Ph.s. Ch.m. 97, 2204 （1993）]. Unexpectedly, th. stretch.ng excitation reduces th. rotation excitation of product h. at th. same total energy.

关键词： State-to-state Differential cross section Time-dependent wave-packet meth.d

Snap-th.ough.beh.viors and nonlinear vibrations of a bistable composite laminated cantilever sh.ll:an experimental and numerical study

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Applied Math.matics and Mech.nics(English.Edition) 2024年第5期45卷 779-794页

作者： Lele REN Wei zhang Ting dong Yufei zhang State Key Laboratory of Mech.nical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Department of Mech.nics Guangxi UniversityNanning 530004China Beijing Key Laboratory of Nonlinear Vibrations and Strength.of Mech.nical Structures College of Mechanical EngineeringBeijing University of TechnologyBeijing 100124China Sch.ol of Mech.nical Engineering Beijing Institute of TechnologyBeijing 100081China

Th. snap-th.ough.beh.viors and nonlinear vibrations are investigated for a bistable composite laminated cantilever sh.ll subjected to transversal foundation excitation based on experimental and th.oretical *** improved experimental specimen is designed in order to satisfy th. cantilever support boundary condition,wh.ch.is composed of an asymmetric region and a symmetric *** symmetric region of th. experimental specimen is entirely clamped,wh.ch.is rigidly connected to an electromagnetic sh.ker,wh.le th. asymmetric region remains free of *** motion path. are realized for th. bistable cantilever sh.ll by ch.nging th. input signal levels of th. electromagnetic sh.ker,and th. displacement responses of th. sh.ll are collected by th. laser displacement *** numerical simulation is conducted based on th. establish.d th.oretical model of th. bistable composite laminated cantilever sh.ll,and an off-axis th.ee-dimensional dynamic snap-th.ough.domain is *** numerical solutions are in good agreement with.th. experimental *** nonlinear stiffness ch.racteristics,dynamic snap-th.ough.domain,and ch.os and bifurcation beh.viors of th. sh.ll are quantitatively *** to th. asymmetry of th. boundary condition and th. sh.ll,th. upper stable-state of th. sh.ll exh.bits an obvious soft spring stiffness ch.racteristic,and th. lower stable-state sh.ws a linear stiffness ch.racteristic of th. sh.ll.

关键词： bistable composite laminated cantilever sh.ll snap-th.ough.beh.vior nonlinear vibration nonlinear stiffness ch.racteristic ch.os and bifurcation

Analysis and experimental study on resistance-increasing beh.vior of composite h.gh.efficiency autonomous inflow control device

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Petroleum Science 2024年第2期21卷 1290-1304页

作者： Liang-Liang dong Yu-Lin zhang Sch.ol of Mech.tronic Engineering Southwest Petroleum UniversityChengdu610500SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina Oil and Gas Equipment Tech.ology Sharing and Service Platform of Sichuan ProvinceChengdu610500SichuanChina

Bottom water coning is th. main reason to reduce th. recovery of h.rizontal bottom water reservoir. By water coning, we mean th. oil-water interface ch.nges from a h.rizontal state to a mound-sh.ped cone and breaks th.ough.to th. wellbore. Autonomous inflow control device(AICD) is an important instrument maintain normal production after bottom water coning, h.wever, th. resistance increasing ability of th. swirl type AICD is insufficient at present, wh.ch.seriously affects th. water control effect. Aiming th.s problem, th.s paper designs a multi-stage resistance-increasing and composite type AICD. Th. separation mech.nism of oil-water two ph.ses in th.s structure, th. resistance form of oil-water single ph.se and th. resistance-increasing principle of water ph.se are analyzed. Establish.ng th. dual-ph.se multi-stage separation and resistance-increasing model, and verified by measuring th. th.ottling pressure drop and oil-water volume fraction of th. AICD, it is found th.t th. composite type AICD h.s th. effect of ICD and AICD at th. same time, wh.ch.can balance th. production rate of each.well section at th. initial stage of production, delay th. occurrence of bottom water coning. In th. middle and later stages of production, water-blocking can be effectively increased to ach.eve water control and stable *** structural sensitivity analysis, th. influence law of various structural parameters on th. water control performance of composite AICD was obtained. Th. simulation calculation results sh.w th.t,compared with.th. existing swirl type AICD, composite AICD h.s h.gh.r sensitivity to moisture content,th. water ph.se th.ottling pressure drop is increased by 4.5 times on average. Th. composite AICD is suitable for th. entire stage of h.rizontal well production.

关键词： Water control Flow separation Flow resistance-increasing AICD device Simulation and experiment

Combustion ch.racteristics of millimeter-sized aluminum particles in fluidized bed under various O_(2)/CO_(2)/h.(2)O atmosph.res Auth.r links open overlay panel

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Particuology 2024年第8期91卷 315-322页

作者： Jialing Zh.u Rui zhang dong Liu Key Laboratory of Th.rmal Control of Electronic Equipment Ministry of Industry and Information TechnologyNanjing210094China Advanced Combustion Laboratory School of Energy and Power EngineeringNanjing University of Science and TechnologyNanjing210094China

Aluminum is an attractive alternative fuel,but it burns very inefficiently due to th. formation of a dense Al_(2)O_(3)layer wh.ch.prevents O_(2)from diffusion to th. surface of Al *** previous experiments,th. combustion of millimeter-sized Al(mAl)particles in th. fluidized bed h.s ach.eved a substantial increase in th. combustion efficiency,but furth.r improvements are still *** th.s study,th. effects of reaction atmosph.re on th. fluidized combustion of mAl particles were *** experiments with.different O_(2)/h.(2)O/CO_(2)concentrations were *** experimental results indicate th.t th. combustion efficiency of mAl particles in fluidized bed increases as th. mole fraction of O_(2),h.(2)O or CO_(2)increases,and th. h.gh.st combustion efficiency can reach.38.7%.After th. analysis of th. oxide film on th. surface of aluminum particles,it was found th.t it is easier to generate th. unstableθ-Al_(2)O_(3)under CO_(2)atmosph.re,and it is easier to generate th. unstableγ-Al_(2)O_(3)andθ-Al_(2)O_(3)under h.(2)O *** unstable Al_(2)O_(3)film is more likely to be abraded in th. fluidized bed,wh.ch.leads to th. effective improvement of th. combustion efficiency.

关键词： Al combustion Fluidized bed Atmosph.re Combustion efficiency

Meta-path.reasoning of knowledge graph.for commonsense question answering

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Frontiers of Computer Science 2024年第1期18卷 49-59页

作者： Miao zhang Tingting h. Ming dong National Engineering Research.Center for E-Learning Central China Normal UniversityWuhan 430079China h.bei Provincial Key Laboratory of Artificial Intelligence and Smart Learning Central China Normal UniversityWuhan 430079China National Language Resources Monitoring&Research.Center for Network Media Central China Normal UniversityWuhan 430079China Sch.ol of Computer Central China Normal UniversityWuhan 430079China

Commonsense question answering(CQA)requires understanding and reasoning over QA context and related commonsense knowledge,such.as a structured Knowledge Graph.KG).Existing studies combine language models and graph.neural networks to model ***,traditional knowledge graph.are mostly concept-based,ignoring direct path.evidence necessary for accurate *** th.s paper,we propose MRGNN(Meta-path.Reasoning Graph.Neural Network),a novel model th.t compreh.nsively captures sequential semantic information from concepts and *** MRGNN,meta-path. are introduced as direct inference evidence and an original graph.neural network is adopted to aggregate features from both.concepts and path. *** conduct sufficient experiments on th. CommonsenceQA and OpenBookQA datasets,sh.wing th. effectiveness of ***,we conduct furth.r ablation experiments and explain th. reasoning beh.vior th.ough.th. case study.

关键词： question answering knowledge graph graph.neural network meta-path.reasoning

A SIMPLE ITERATIVE ALGORITh. FOR MAXCUT

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Journal of Computational Math.matics 2024年第5期42卷 1277-1304页

作者： Sih.ng Sh.o dong zhang Weixi zhang CAPT LMAM and School of Mathematical SciencesPeking UniversityBeijing 100871China LMAM and Sch.ol of Math.matical Sciences Peking UniversityBeijing 100871China

We propose a simple iterative(SI)algorith. for th. maxcut problem th.ough.fully using an equivalent continuous *** does not need rounding at all and h.s advantages th.t all subproblems h.ve explicit analytic solutions,th. cut values are monotonically updated and th. iteration points converge to a local optima in finite steps via an appropriate subgradient *** experiments on G-set demonstrate th. *** particular,th. ratios between th. best cut values ach.eved by SI and th.se by some advanced combinatorial algorith.s in[***.,248(2017),365-403]are at least 0.986 and can be furth.r improved to at least 0.997 by a preliminary attempt to break out of local optima.

关键词： Maxcut Iterative algorith. Exact solution Subgradient selection Fractional programming

Metal-based inorganic nanocrystals for biological sonodynamic th.rapy applications:recent progress and perspectives

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Rare Metals 2024年第2期43卷 413-430页

作者： dong Wang Jia-Tao zhang Institute of Medical-Industrial Integration Beijing Key Laboratory of Structurally Controllable Advanced Functional Materials and Green ApplicationsSchool of Materials Science and EngineeringBeijing Institute of TechnologyBeijing100081China Key Laboratory of Medical Molecule Science and Ph.rmaceutics Engineering Ministry of Industry and Information TechnologySchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing100081China

With.th. fast development of tech.ology for th. treatment of tumor and bacteria,ph.to-th.rapeutic strate-gies emerge as a kind of h.gh.y effective and common treatment,but th. low tissue penetration depth.of ligh. limits th.ir *** th.rapy(SDT),as an efficient and non-invasive treatment,attracts more people's attention due to th. inh.rent property of h.gh.tissue *** soft tissue penetration depth.of ultrasound(US)can even reach.more th.n 10 cm,wh.ch.h.s great advantage over th.t of ***,many sonosensitizers are studied and applied to SDT-based ***-based inorganic nanocrystals are able to generate more reactive oxygen species(ROS)due to th. special composition and band *** representative ach.evements and th. specific functions of th. nanocrystals sonosensitizers are summarized in th.s work,and th. relationsh.p of structure/composition-SDT performance and th. internally regulated composite is ***-gistic effects of SDT in combination with.oth.r th.rapeutic modalities are mainly *** th. same time,th. critical and potential issues and future perspectives are addressed.

关键词： Metal-based inorganic nanocrystals Sonodynamic th.rapy(SDT) Tumor treatment Antibacteria

Multi-modal visual tracking:Review and experimental comparison

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Computational Visual Media 2024年第2期10卷 193-214页

作者： Pengyu zhang dong Wang h.ch.an Lu Faculty of Electronic Information and Electrical Engineering Dalian University of TechnologyDalian 116024Chin

Visual object tracking h.s been drawing increasing attention in recent years,as a fundamental task in computer *** extend th. range of tracking applications,research.rs h.ve been introducing information from multiple modalities to h.ndle specific scenes,with.promising research.prospects for emerging meth.ds and *** provide a th.rough.review of multi-modal tracking,different aspects of multi-modal tracking algorith.s are summarized under a unified taxonomy,with.specific focus on visibledepth.RGB-D)and visible-th.rmal(RGB-T)***,a detailed description of th. related bench.arks and ch.llenges is *** experiments were conducted to analyze th. effectiveness of trackers on five datasets:PTB,VOT19-RGBD,GTOT,RGBT234,and ***,various future directions,including model design and dataset construction,are discussed from different perspectives for furth.r research.

关键词： visual tracking object tracking multi-modal fusion RGB-T tracking RGB-D trackin