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International Journal of Minerals,Metallurgy and Materials 2022年第2期29卷 256-262页

作者： Huixiang Yu Dexin Yang jiaming zhang Guangyuan Qiu Ni zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The effect of Al content(0.035 wt%,0.5 wt%,1 wt%,and 2 wt%)on the composition change of steel and slag as well as inclusion transformation of high manganese steel after it has equilibrated with Ca O-Si O_(2)-Al_(2)O_(3)-Mg O slag was studied using the method of slag/steel *** experimental results showed that as the initial content of Al increased from 0.035 wt%to 2 wt%,Al gradually replaced Mn to react with Si O_(2)in slag to avoid the loss of Mn due to the reaction;this process caused both Al_(2)O_(3)in slag and Si in steel to increase while Si O_(2)and Mn O in slag to *** addition,the type of inclusions also evolved as the initial Al content *** evolution route of inclusions was Mn O→Mn O-Al_(2)O_(3)-Mg O→Mg O→Mn O-Ca O-Al_(2)O_(3)-Mg O and Mn O-Ca O-Mg *** shape of inclusions evolved from spherical to irregular,became faceted,and finally transformed to *** average size of inclusions presented a trend that was increasing first and then *** transformation mechanism of inclusions was *** the initial content of Al increased,Mg and Ca were reduced from top slag into molten steel in sequence,which consequently caused the transformation of inclusions.

关键词： medium/high manganese steel Al content steel composition slag composition non-metallic inclusion slag/steel reaction

Weapon configuration, allocation and route planning with time windows for multiple unmanned combat air vehicles

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Journal of Systems Engineering and Electronics 2018年第5期29卷 953-968页

作者： zhang jiaming LIU Zhong SHI Jianmai CHEN Chao Science and Technology on Information Systems Engineering Laboratory National University of Defense Technology

Unmanned combat air vehicles(UCAVs) mission planning is a fairly complicated global optimum problem. Military attack missions often employ a fleet of UCAVs equipped with weapons to attack a set of known targets. A UCAV can carry different weapons to accomplish different combat missions. Choice of different weapons will have different effects on the final combat effectiveness. This work presents a mixed integer programming model for simultaneous weapon configuration and route planning of UCAVs, which solves the problem optimally using the IBM ILOG CPLEX optimizer for simple missions. This paper develops a heuristic algorithm to handle the medium-scale and large-scale problems. The experiments demonstrate the performance of the heuristic algorithm in solving the medium scale and large scale problems. Moreover, we give suggestions on how to select the most appropriate algorithm to solve different scale problems.

关键词： unmanned combat air vehicles(UCAVs) mission planning route planning weapon configuration time windows

Early-Middle Paleozoic Andes-type Continental Margin in the Chifeng Area, Inner Mongolia: Framework, Geochronology and Geochemistry and Implications for Tectonic Evolution of the Central Asian Orogenic Belt

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Acta Geologica Sinica(English Edition) 2020年第1期94卷 57-74页

作者： YAN Linjie XU Bei zhang jiaming WANG Yanyang Key Laboratory of Orogenic Belts and Evolution Peking UniversityBeijing 100871China Key Laboratory of Regional Geology and Mineralization Hebei GEO UniversityShijiazhuang 050031China

Three tectonic units have been recognized in the Chifeng area, Inner Mongolia, from north to south, including the Qiganmiao accretionary prism, Jiefangyingzi arc belt and Sidaozhangpeng molasse basin, which formed an Andeantype active continent margin during the early to middle Paleozoic. The Qiganmiao accretionary prism is characterized by a mélange that consists of gabbro, two-mica quartz schist and basic volcanic rock blocks and heterogeneously deformed marble matrix. Two zircon U-Pb ages of 446.0±6.3 Ma and 1104±27 Ma have been acquired and been interpreted as the metamorphic and forming ages for the gabbro and two-mica quartz schist, respectively. The prism formed during the early to middle Paleozoic southward subduction of the Paleo Asian Ocean(PAO) and represents a suture between the North China craton(NCC) and Central Asian Orogenic Belt(CAOB). The Jiefangyingzi arc belt consists of pluton complex and volcanic rocks of the Xibiehe and Badangshan Formations, and Geochronology analysis indicates that the development of it can be divided into two stages. The first stage is represented by the Xibiehe Formation volcanic rocks, which belong to the subalkaline series, enriched LREE and LILE and depleted HFSE, with negative Eu anomalies, and plot in the volcanic arc field in discrimination diagrams. These characters indicate that the Xibiehe Formation results from to the continental arc magmatic activity related to the subduction of the PAO during 400–420 Ma. Magmatism of the second stage in 380–390 Ma consists of the Badangshan Formation volcanic rocks. Geochemistry analysis reveals that rhyolite, basaltic andesite and basalt of the Badangshan Formation were developed in continental margin arc setting. Moreover, the basaltic andesite and basalt display positive Sr anomalies, and the basalt have very low Nb/La values, suggesting that fluid is involved in magma evolution and the basalts were contaminated by continental crust. The sequence of Sidaozhangpeng molasse ba

关键词： Chifeng area andes-type continental margin early-middle paleozoic tectonic evolution Central Asian Orogenic Belt

Effect of wire mesh casing treatment on axial compressor performance and stability

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Chinese Journal of Aeronautics 2024年第3期37卷 60-76页

作者： Ming zhang jiaming zhang Jiahao HU Xu DONG Dakun SUN Xiaofeng SUN School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beihang Hangzhou Innovation Institute Yuhang Hangzhou 310023China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 100191China

In this paper,a kind of Wire Mesh Casing Treatment(WMCT)is proposed to improve the stable operating range of the *** contrast to the traditional circumferential groove,as for WMCT,a layer of wire mesh is laid on the surface of the circumferential *** studies were conducted on the low-speed axial flow compressor,including the groove width,axial location,and mesh *** optimum axial location for WMCT is related to its groove width.A higher wire mesh count results in a smaller compressor stall margin *** simulations were carried out to study the effect of WMCT on the flow structure of the *** wire mesh in the WMCT has a certain flow resistance,which restricts the flow into and out of the *** to the WMCT,the flow parameter in the tip region of the rotor is less sensitive to changes in the operating conditions of the *** WMCT causes the rotor tip blade loading to shift backward,inhibiting the formation of spill forward of the leakage flow,and thus improving the stability of the *** flow resistance on the groove surface is a new degree-of-freedom for the casing treatment designer.

关键词： Axial compressor Wire mesh casing treatment Tip clearance flow Stall margin Blade loading

Joint mission and route planning of unmanned air vehicles via a learning-based heuristic

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Journal of Systems Engineering and Electronics 2023年第1期34卷 81-98页

作者： SHI Jianmai zhang jiaming LEI Hongtao LIU Zhong WANG Rui College of Systems Engineering National University of Defense TechnologyChangsha 410073China

Unmanned air vehicles(UAVs) have been regularly employed in modern wars to conduct different missions. Instead of addressing mission planning and route planning separately,this study investigates the issue of joint mission and route planning for a fleet of UAVs. The mission planning determines the configuration of weapons in UAVs and the weapons to attack targets, while the route planning determines the UAV’s visiting sequence for the targets. The problem is formulated as an integer linear programming model. Due to the inefficiency of CPLEX on large scale optimization problems, an effective learningbased heuristic, namely, population based adaptive large neighborhood search(P-ALNS), is proposed to solve the model. In P-ALNS, seven neighborhood structures are designed and adaptively utilized in terms of their historical performance. The effectiveness and superiority of the proposed model and algorithm are demonstrated on test instances of small, medium and large sizes. In particular, P-ALNS achieves comparable solutions or as good as those of CPLEX on small-size(20 targets)instances in much shorter time.

关键词： unmanned air vehicle(UAV) mission planning routing adaptive large neighborhood search

New measurements on hydrodynamics in a gas-liquid-solid expanded bed

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Particuology 2021年第5期19卷 276-284页

作者： Xiuhong Zhou Yongli Ma Mingyan Liu Yixian Zhu jiaming zhang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China State Key Laboratory of Chemical Engineering Tianjin UniversityTianjin 300350China China Energy Longyuan Environmental Protection Co. Ltd.Beijing 100039China

The solid holdup,in a 150 mm-ID×2460 mm-height gas-liquid-solid expanded bed with air,water and glass beads(the diameter of particles is 0.6-0.8 mm)was firstly investigated based on the immersion-type online multiphase measuring instrument,and bubble behavior was studied via the BVW-2 double electrical conductivity *** effect of the superficial gas velocity and liquid velocity on the expanded ratio,the transition ratio,the bubble rising velocity,the gas holdup and the solid holdup was *** is discovered that compared with the gas velocity,the liquid velocity has stronger impact on the expanded ratio,but it is opposite for the transition *** average gas holdup and solid holdup increase linearly as the superficial gas velocity goes *** it,the gas holdup increases greater in the center,while the solid holdup increases greater near the *** with it,when the superficial liquid velocity rises,the average gas holdup hardly changes,but the average solid holdup keeps decreasing,especially the solid holdup distributes flatter with the increase of the superficial liquid velocity.

关键词： Phase holdup Gas-liquid-solid expanded bed Immersion-type online multiphase measuring instrument BVW-2 double electrical conductivity probe

Quantumness protection for open systems in a double-layer environment

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Science China(Physics,Mechanics & Astronomy) 2020年第5期63卷 47-58页

作者： YuLong Qiao jiaming zhang YuSui Chen Jun Jing ShiYao Zhu Zhejiang Province Key Laboratory o f Quantum Technology and Device Department of PhysicsZhejiang UniversityHangzhou 310027China Department of Physics New York Institute of TechnologyOld Westbury NY 11568USA

We study the dynamics of two-level atomic systems(qubits) subject to a double-layer environment that consists of a network of single-mode cavities coupled to a common reservoir. A general exact master equation for the dynamics of a qubit system can be obtained by the quantum-state-diffusion(QSD) approach, which is extended to our spin-cavity-boson model. The quantumness of the atoms comprising coherence and entanglement is investigated for various configurations of the double-layer *** findings indicate that parametric control is available for the preservation and generation of system-quantumness by regulating the cavity network. Moreover the underlying physics is profoundly revealed by an effective model obtained by a unitary transformation. Therefore, our work provides an interesting proposal to protect the quantumness of open systems in the framework of a double-layer environment containing bosonic modes.

关键词： quantum-state-diffusion equation open quantum systems decoherence quantum noise

17~45岁肥胖门诊患者的6分钟步行试验距离参考方程研究

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中国全科医学 2025年第3期28卷 330-334,345页

作者：张家鸣王欣宇王道荣孙晓芳扬州大学医学院江苏省扬州市225009 江苏省苏北人民医院内分泌科江苏省扬州市225001

背景目前6分钟步行试验(6MWT)已经被广泛用于评估肥胖人群的运动能力,并为制订干预措施提供了参考依据。国外已有研究提出了其他人群的6MWT距离参考方程,但中国17~45岁且BMI≥30 kg/m^(2)肥胖受试者的6MWT距离参考方程研究较少。目的 ... 详细信息

背景目前6分钟步行试验(6MWT)已经被广泛用于评估肥胖人群的运动能力,并为制订干预措施提供了参考依据。国外已有研究提出了其他人群的6MWT距离参考方程,但中国17~45岁且BMI≥30 kg/m^(2)肥胖受试者的6MWT距离参考方程研究较少。目的为17~45岁门诊肥胖受试者制订6MWT距离参考方程,并评估其影响因素。方法根据美国胸科学会指南,前瞻性选取2022年6月—2023年9月于江苏省苏北人民医院内分泌科肥胖门诊部就诊的143名年龄17~45岁且BMI≥30 kg/m^(2)的成年人(71名男性和72名女性),进行人体测量和6MWT。采用逐步多元回归模型建立6MWT距离参考方程,将新建立的6MWT距离参考方程与现有的预测方程进行比较。结果 143名受试者的平均6MWT距离为(506.1±49.8)m,其中男性平均6MWT距离为(515.7±50.1)m,大于女性的平均6MWT距离(496.6±47.9)m(P<0.05)。在年龄段17~23岁、24~30岁、31~37岁以及38~45岁中,男性与女性6MWT距离比较,差异均有统计学意义(P<0.05)。男性受试者的体质量、BMI、最大心率(HR_(max))、心率差(ΔHR)、腰围、舒张压差(ΔDBP)、Borg量表评分差(ΔBorg)与6MWT距离相关(P<0.05),女性受试者的体质量、BMI、腰围与6MWT距离相关(P<0.05)。以步进的方法将潜在的影响因素纳入多元线性回归方程中,最终建立6MWT距离参考公式:男性y=494.463+1.414×ΔHR-3.903×BMI+0.874×HR_(max),R^(2)=0.429,女性y=670.448+0.299×ΔHR-4.342×BMI-0.195×HR_(max),R^(2)=0.312。结论 17~45岁门诊肥胖受试者中,男性的平均6MWT距离长于女性,且在不同年龄段均有显著差异。男性的体质量、BMI、HR_(max)、ΔHR、腰围、ΔDBP、ΔBorg与6MWT距离相关,女性的体质量、BMI、腰围、ΔSBP与6MWT距离相关。通过多元线性回归分析,为男性和女性分别建立了预测6MWT距离的参考方程,这些公式可能为评估个体的体能水平提供有价值的参考。

关键词：肥胖症步行试验距离方程 17~45岁 6分钟步行试验影响因素分析

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Effect of Zr on phase separation,mechanical and corrosion behavior of heterogeneous CoCrFeNiZr_(x) high-etropy alloy

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Journal of Materials Science & Technology 2022年第14期109卷 76-85页

作者： Wu Qi Wenrui Wang Xiao Yang Lu Xie jiaming zhang Dongyue Li Yong zhang School of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of Fluid Interaction with Material Ministry of EducationBeijing 100083China Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

CoCrFeNi high entropy alloy(HEA)has attracted extensive attention due to its excellent corrosion resistance,but the low strength limits its engineering application *** order to develop CoCrFeNi based HEAs with high strength,ductility and corrosion resistance,the effects of Zr content on the microstructure,mechanical properties and corrosion resistance of heterogeneous CoCrFeNiZr_(x)(x=0,0.25,0.5 and 1)HEAs were investigated in this *** results indicate that the increase of Zr content can significantly affect the phase stability of the alloy,and promote the formation of intermetallic compounds(Ni_(7)Zr_(2)and/or Laves phase)and the transformation of solid solution from face-centered cubic(FCC)structure(x=0,0.25 and 0.5)to body-centered cubic(BCC)structure(x=1).Reasonable control of the Zr content can endow the alloy excellent comprehensive ***,for CoCrFeNiZr_(0.25) alloy,composed of FCC matrix and a small amount of Ni_(7)Zr_(2)phases,the yield strength(~655 MPa)is increased by nearly four times higher than that of Zr-free alloy,and it also has good ductility(fracture stain>50%).Meanwhile,the corrosion resistance of CoCrFeNiZr_(0.25) alloy is better than that of *** EIS results show that the addition of Zr reduces the stability of the passive film on the alloy,which can be related to the content of the beneficial oxide in the passive film and the thickness of the passive film through XPS ***,the work functions of different phases in CoCrFeNiZr_(x)alloys were obtained by firstprinciples calculations,which further confirmed the selective corrosion mechanism of the CoCrFeNiZr_(x) alloy combining the experimental results.

关键词： High-entropy alloy Microstructure Corrosion resistance First-principles Work function

NH_(4)Cl-assisted synthesis of TaON nanoparticle applied to photocatalytic hydrogen and oxygen evolution from water

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Journal of Energy Chemistry 2024年第7期94卷 541-550页

作者： Yao Xu Kaiwei Liu Jifang zhang Boyang zhang jiaming zhang Ke Shi Haifeng Wang Guijun Ma School of Physical Science and Technology Shanghaitech UniversityShanghai 201210China

Oxynitride semiconductors are promising photocatalyst materials for visible light-driven water splitting,while the synthesis of well crystalized oxynitride still remains *** present work,narrow-bandgap TaON nanoparticles are synthesized via heating a vacuum-sealed mixture of KTaO_(3),Ta and NH_(4)*** method possesses multiple advantages in terms of lower calcination parameter,higher N conversion efficiency and superior photocatalytic activity in comparison with the traditional thermal ammonolysis using NH_(3) gas as a nitrogen *** the analysis of intermediates produced upon the elevation of heating temperature,a gas-solid-phase reaction between TaCl_(5) and Ta_(2)O_(5) is demonstrated as the final step,which is conducive to decreasing thermal energy barrier and accelerating nitridation *** control of preparation conditions,including calcination temperature and duration,allows for the regulation of surface O/N ratio of TaON particles to unity,resulting in optimized photocat-alytic *** assessment and intensity modulated photocurrent spectroscopy provide convincing evidence for improved charge transfer effciency of photoexcited holes at TaON surface.A Z-scheme overall water splitting is accomplished by employing the TaON as an effective oxygen evolution photocatalyst,SrTiO_(3):Rh as a hydrogen evolution photocatalyst,and reduced graphene oxide(rGO)as a solid-state electron *** work presents a promising strategy for the synthesis of high-quality oxynitride materials in application to photocatalytic water splitting.

关键词： TaON Oxynitride synthesis Photocatalyst Water splitting,Hydrogen Z-scheme