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Preparation of Ga_2O_3 thin film solar-blind photodetectors based on mixed-phase structure by pulsed laser deposition

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Chinese Physics B 2019年第1期28卷 171-177页

作者： y M Lu C Li X H Chen S Han P J Cao F Jia y X Zeng X K Liu w y xu w J Liu D L Zhu College of Materials Science and Engineering Shenzhen Key Laboratory of Special Functional MaterialsShenzhen Engineering Laboratory for Advanced Technology of CeramicsGuangdong Research Center for Interfacial Engineering of Functional MaterialsShenzhen UniversityShenzhen 518060China

Gallium oxide(Ga_2O_3) thin films were deposited on a-Al2O3(1120) substrates by pulsed laser deposition(PLD) with different oxygen pressures at 650?C. By reducing the oxygen pressure, mixed-phase Ga_2O_3 films with α and β phases can be obtained, and on the basis of this, mixed-phase Ga_2O_3 thin film solar-blind photodetectors(SBPDs) were *** the responsivities of the mixed-phase Ga_2O_3 SBPDs and the single β-Ga_2O_3 SBPDs at a bias voltage of 25 V,it is found that the former has a maximum responsivity of approximately 12 A/w, which is approximately two orders of magnitude larger than that of the latter. This result shows that the mixed-phase structure of Ga_2O_3 thin films can be used to prepare high-responsivity SBPDs. Moreover, the cause of this phenomenon was investigated, which will provide a feasible way to improve the responsivity of Ga_2O_3 thin film SBPDs.

关键词： Ga2O3 mixed-phase solar-blind photodetector pulsed laser deposition

The magnetic local time distribution of ring current during the geomagnetic storm

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The magnetic local time distribution of ring current during ...

Conventional and micro scale finite element modeling for metal cutting process:A review

中国科学院地质与地球物理研究所2013年度（第13届）学术年会

作者： X.D.Zhao A.M.Du w.y.xu Institute of Geology and Geophysics Chinese Academy of Sciences Institute of Geophysics China Earthquake Administration

The magnetic local time distribution of the ring current during 879 geomagnetic storms(identified by SyMH < -30 nT) in the 23rd solar cycle(1996-2006) was investigated by using 23 mid-low latitude ground-based *** sto... 详细信息

The magnetic local time distribution of the ring current during 879 geomagnetic storms(identified by SyMH ycle(1996-2006) was investigated by using 23 mid-low latitude ground-based *** storms are divided into eight different classes with a step of 20 nT for the statistical *** each class,the dusk side events,for which the H component minimum located in the dusk sector is mostly corresponding to the UT of minimum SyMH index,are about 59.5% of the total *** the noon side events are about 20.0%,the night side events are about 18.7%, and the dawn side events are about 1.8%.The H component distributions with MLT indicate that the magnetic field disturbance during the magnetic storm events is not only related to the symmetrical ring current,but also to the other current,mainly the partial current.A further statistical study of the dusk side events shows that both the symmetric and partial ring currents enhance accompanied by the increase in the storm class during the main *** the partial ring current makes a greater contribution to the main phase of the *** to the interplanetary parameters,the distinction of the solar wind velocity V is more obvious than the interplanetary magnetic field B for the dusk side events in different *** comparisons between dusk side and other side events in the same class indicate that besides the solar wind velocity V,the interplanetary magnetic field B also affects on the disturbance of ring current on the ground in MLT.

关键词： Ring current Storm Magnetic local time Magnetic field

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Chinese Journal of Aeronautics 2024年第2期37卷 199-232页

作者： Le wANG Caixu yUE Xianli LIU Ming LI yongshi xu Steven y.LIANG Key Laboratory of Advanced Manufacturing and Intelligent Technology Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China George w.woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlanta 30332USA

The metal cutting process is accompanied by complex stress field,strain field,temperature *** comprehensive effects of process parameters on chip morphology,cutting force,tool wear and residual stress are complex and *** element method(FEM)is considered as an effective method to predict process variables and reveal microscopic physical phenomena in the cutting ***,the finite element(FE)simulation is used to research the conventional and micro scale cutting process,and the differences in the establishment of process variable FE simulation models are distinguished,thereby improving the accuracy of FE *** reliability and effectiveness of FE simulation model largely depend on the accuracy of the simulation method,constitutive model,friction model,damage model in describing mesh element,the dynamic mechanical behavior of materials,the tool-chip-workpiece contact process and the chip formation *** this paper,the FE models of conventional and micro process variables are comprehensively and up-to-date reviewed for different materials and machining *** purpose is to establish a FE model that is more in line with the real cutting conditions,and to provide the possibility for optimizing the cutting process *** development direction of FE simulation of metal cutting process is discussed,which provides guidance for future cutting process modeling.

关键词： Conventional and micro scale Finite element simulation Metal cutting process Micro cutting Modeling

Optimal Coordination of Transportable Power Sources and Repair Crews for Service Restoration of Distribution Networks Considering Uncertainty of Traffic Congestion

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 189-201页

作者： Zhao Shi yan xu Dunjian Xie Shiwei Xie Amer M.y.M.Ghias Nanyang Technological University Singapore the School of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108China

This paper proposes a new method for service restoration of distribution network with the support of transportable power sources(TPSs)and repair crews(RCs).Firstly,a coupling model of distribution networks and vehicle routing of TPSs and RCs is proposed,where the TPSs serve as emergency power supply sources,and the RCs are used to repair the faulted *** the uncertainty of traffic congestion,the probability distribution of the travel time spent on each road is derived based on the Nesterov user equilibrium model,and a two-stage stochastic program is formulated to determine the optimal routings of TPSs and *** efficiently solve the proposed stochastic mixed-integer linear program(MILP),a two-phase scenario reduction method is then developed to scale down the problem size,and an adaptive progressive hedging algorithm is used for an efficient *** effectiveness of the proposed methods and algorithms has been illustrated in a modified IEEE 33-bus system.

关键词： Service restoration distribution network traffic uncertainty transportable power source repair crew stochastic program

Cognition on oxidation behavior of Ni-based superalloy GH4742 when exposed to water vapor

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Journal of Materials Science & Technology 2024年第7期174卷 15-22页

作者： H.xu S.F.yang E.H.wang C.y.Guo y.S.Liu X.M.Hou y.L.Zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China

The oxidation behavior of Ni-based superalloy GH4742 exposed to water vapor was investigated at 900-1100℃for 50 h in Ar+20%H_(2)O,with Ar+20%O_(2)included for *** presence of H_(2)O is adverse to formation of continuous Cr_(2)O_(3)oxide layer but contributes to generation of big *** on this,Ni^(2+)and Co^(2+)are more easily to diffuse towards the outermost oxide layer(OOL),forming non-protective Ni-and Co-rich oxides with high *** leads to a higher weight gain in Ar+20%H_(2)O than that in Ar+20%O_(2).At elevated temperatures,the spallation of oxide scale occurs while the consumption of Cr is reduced in Ar+20%H_(2)O,and the contents of Ni-and Co-rich oxides at this moment are reduced in the *** oxidation mechanism was also discussed.

关键词： GH4742 Superalloy H_(2)O Diffusion Oxidation Mechanism

Solar wind dependence of energy coupling between solar wind and magnetosphere during intense northward IMFs

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Solar wind dependence of energy coupling between solar wind ...

Experimental study of corner separation and unsteady characteristics in linear compressor cascades with and without sweeping jet actuator

中国科学院地质与地球物理研究所2013年度（第13届）学术年会

作者： H.Luo G.X.Chen A.M.Du w.y.xu Beijing National Observatory of Space Environment Institute of Geology and GeophysicsChinese Academy of Sciences

we statistically study the solar wind dependence of the magnetospheric activities during intense northward interplanetary magnetic fields(IMFs) events(Bz > 10 nT,last over 3 h).It was found that the energy coupling between solar wind and magnetosphere during intense northward IMFs was mainly controlled by solar wind velocity and IMF clock angle(θ).A northward IMF coupling function was derived based on the dimensional analysis and quantitative analysis of the solar wind parameters and the geomagnetic *** was shown that whenθ>～45°,the energy input increases obviously asθ*** importantly,it was also found that the relative importance between the viscous interaction and the IMF |By| effect in controlling the energy input into the magnetosphere during intense northward IMFs mainly depends on IMF clock *** viscous interaction will outweigh the IMF |By| effect in the northward IMF events with 0 ward IMF events withθ>～75°,the IMF \By\ effect may be more important than the viscous interaction.

关键词： Energy coupling Northward interplanetary magnetic field Viscous interaction IMF |By| effect

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Propulsion and Power Research 2024年第3期13卷 360-374页

作者： S.w.Chen w.H.Li C.xu Q.H.Meng School of Energy Science and Engineering Harbin Institute of TechnologyHarbinHeilongjiang 150001China AVIC Shenyang Aircraft Design and Research Institute Shenyang 110035China

Sweeping jet actuator(SJA)has been widely applied for activeflow control in *** this paper,the SJA character in compressor cascade and its performance for separation control in innerflows are ***-averaged and transientflowfield measurement,together with visualization methods are *** is found that endwall effects are important for both SJA behaviors and SJA performance for separation control in compressor *** is a maximum of 12.7%total pressure loss reduction with SJA placed near the separation position,close to the endwall and under *** characteristic frequencies in theflowfield contribute to the capture of influence regions of vortices and excitation *** concentrated shedding vortices and SJA jets impact region helped to judge that SJA energizes low momentumfluids in a large region and matches the high loss core *** be concrete,theflow separation control mechanism of SJA lies on the interruption of the blade suction surface boundary layer development and the restriction of the lifting of the boundary layer from end-wall towards blade suction surface.

关键词： Compressor cascade Activeflow control Sweeping jet actuator Corner separation Oilflow visualization

Riverine sulfate sources and behaviors in arid environment,Northwest China:Constraints from sulfur and oxygen isotopes

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Journal of Environmental Sciences 2024年第3期137卷 716-731页

作者： yifu xu wenjing Liu Bing xu Zhifang xu Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

The fate of riverine sulfate ion (SO_(4)^(2-)) and its environmental effects in arid environment are difficult to evaluate due to its complicated sources and strongly coupled behaviors with water cycle which is significantly modified by *** understand the sulfur cycle in aquatic systems in arid environment,the chemical and sulfur and oxygen isotopic compositions (δ^(34)S_(SO4)and δ^(18)O_(SO4)) of major rivers around the Badain Jaran Desert,northwestern China,were *** rivers had averaged SO_(4)^(2-)content at 1336μmol/L,over 10times higher than the global *** δ^(34)S_(SO4)and δ^(18)O_(SO4)values ranged from-5.3‰to+11.8‰and+1.6‰to+12.8‰,*** end-member analysis and the inverse model showed that riverine sulfate was mainly derived from evaporites dissolution (0-87%),sulfide oxidation (13%-100%) and precipitation (0-33%),indicating heterogeneity in sulfur sources and behaviors along the river drainage with the lithology variations and climate *** isotopic tools combining with hydro-chemistry compositions could be applied to reveal sulfur cycle in arid *** on the calculation,sulfide oxidation plays the primary role in the headwater and upstream in the Qilian-Mountains area,where sulfide is widely *** the proportion of evaporites dissolution contributing to riverine sulfate is much higher in downstream in a drier ***,less precipitation and higher temperature can lead to more intensive evaporation,affecting the process of sulfide oxidation and enhancing the rates of evaporites dissolution and sulfate precipitation in the basin.

关键词： Sulfur and oxygen isotopes Source apportionment Inverse model Arid environment Inland rivers Northwestern China

Mineral-mediated stability of organic carbon in soil and relevant interaction mechanisms

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Eco-Environment & Health 2024年第1期3卷 59-76页

作者： Zibo xu Daniel C.w.Tsang Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyClear Water BayHong KongChina

Soil,the largest terrestrial carbon reservoir,is central to climate change and relevant feedback to environmental *** are the essential components that contribute to over 60%of soil carbon ***,how the interactions between minerals and organic carbon shape the carbon transformation and stability remains poorly ***,we critically review the primary interactions between organic carbon and soil minerals and the relevant mechanisms,including sorption,redox reaction,co-precipitation,dissolution,polymerization,and catalytic *** interactions,highly complex with the combination of multiple processes,greatly affect the stability of organic carbon through the following processes:(1)formation or deconstruction of the mineral–organic carbon association;(2)oxidative transformation of the organic carbon with minerals;(3)catalytic polymerization of organic carbon with minerals;and(4)varying association stability of organic carbon according to the mineral *** pieces of evidence related to the carbon turnover and stability during the interaction with soil minerals in the real eco-environment are then *** also highlight the current research gaps and outline research priorities,which may map future directions for a deeper mechanismsbased understanding of the soil carbon storage capacity considering its interactions with minerals.

关键词： Carbon stability Mineral transformation Carbon sequestration Bio-geochemistry Soil carbon management Sustainable waste management