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Growth process,defects,and dopants of bulkβ-Ga_(2)O_(3)semiconductor single crystals

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China Foundry 2024年第5期21卷 491-506页

作者： Yan-shen Wang ming-zhi Zhu Yuan Liu School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) Beijing 100084China

β-gallium oxide(β-Ga2O3),as the typical representative of the fourth generation of semiconductors,has attracted increasing attention owing to its ultra-wide bandgap,superior optical properties,and excellent tolerance to high temperature and *** to the single crystals of other semiconductors,high-quality and large-sizeβ-Ga_(2)O_(3)single crystals can be grown with low-cost melting methods,making them highly *** this review,the growth process,defects,and dopants ofβ-Ga_(2)O_(3)are primarily ***,the growth process(e.g.,decomposition,crucible corrosion,spiral growth,and development)ofβ-Ga_(2)O_(3)single crystals are summarized and compared in ***,the defects ofβ-Ga_(2)O_(3)single crystals and the influence of defects on Schottky barrier diode(SBD)devices are emphatically ***,the influences of impurities and intrinsic defects on the electronic and optical properties ofβ-Ga_(2)O_(3)are also briefly *** this comprehensive analysis,the article offers a concise summary of the current state,challenges and prospects ofβ-Ga_(2)O_(3)single crystals.

关键词： β-Ga_(2)O_(3) single-crystal growth defects dopants semiconductor

Vortex identification based on the Liutex method and its effect on fish passage upstream

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Journal of Hydrodynamics 2024年第1期36卷 130-141页

作者： Chun-ying shen Rui-guo Yang Xiao-tao Shi ming-ming Wang Shi-hua He Faculty of Electrical Power Engineering Kunming University of Science and TechnologyKunming650500China Hubei International Science and Technology Cooperation Base of Fish Passage China Three Gorges UniversityYichang443002China Shanghai Investigation Design and Research Institute Co.LtShanghai200434China

Fishway research is important for mitigating the fragmentation of river habitats caused by hydraulic *** vertical slit fishway is a broadly used fishway type because of its high efficiency and adaptability to water ***,the resulting vortex current disrupts the fish passage hence directly affecting fish *** study aims to accurately capture the vortex structure in the fishway and analyze the effect of vortex elements(vortex structure,vortex intensity,etc.)on *** conducted an analysis of the 3-D current flow field in the fishway through the utilization of an experimental model and the large eddy simulation(LES)***,we captured the vortex information in the fishway at different flow rates using the Liutex vortex identification method and investigated the effect of the vortex on fish *** results revealed that the structures inside the fishway pool occupy most of the room,however,the areas with higher vortex strength were primarily located in the vortex near the vertical seam and the mainstream,the vortex strength inside the fishway gradually increases with increasing flow,suppressing fish *** experienced significantly increased resistance when encountering strong *** suggests that the vortex may act as a physical barrier to fish *** findings highlight the potential negative effects of vortex on fish movement and reiterate the importance of understanding vortex dynamics for aquatic environmental *** an effective tool for identifying vortices in fluid flow,the Liutex method demonstrates features of vortex within the fishway,thereby providing important insights into the interaction between fluid dynamics and aquatic organisms.

关键词： Vertical slit fishway vortex identification method Liutex large eddy simulation(LES) fish experiment computational fluid dynamics

Weakly Approximate Diagonalization of Homomorphisms into Finite von Neumann Algebras

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2187-2194页

作者： Wen Hua QIAN Jun Hao shen Wen ming WU School of Mathematical Sciences Chongqing Normal UniversityChongqing 401331P.R.China Department of Mathematics and Statistics University of New HampshireDurhamNH 03824USA

Let A be a unital C^(∗)-algebra and B a unital C^(∗)-algebra with a faithful traceτ.Let n be a positive *** give the definition of weakly approximate diagonalization(with respect toτ)of a unital homomorphismφ:A→Mn(B).We give an equivalent characterization of McDuff Ⅱ_(1) *** show that,if A is a unital nuclear C^(∗)-algebra and B is a type Ⅱ_(1) factor with faithful traceτ,then every unital^(∗)-homomorphism φ:A→M_(n)(B)is weakly approximately *** B is a unital simple infinite dimensional separable nuclear C^(∗)-algebra,then any finitely many elements in Mn(B)can be simultaneously weakly approximately diagonalized while the elements in the diagonals can be required to be the same.

关键词： Weakly approximately diagonalizable McDuff factors nuclear hyperfinite

Solid-state NMR study on sodium intercalation at low voltage window for Na_(3)V_(2)(PO_(4))_(3) as an anode

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Magnetic Resonance Letters 2024年第2期4卷 40-45页

作者： Yuxin Liao Fushan Geng ming shen Bingwen Hu Shanghai Key Laboratory of Magnetic Resonance State Key Laboratory of Precision SpectroscopySchool of Physics and Electronic ScienceEast China Normal UniversityShanghai200241China

In-situ XRD,^(31)P NMR and ^(23)Na NMR were used to analyze the interaction behavior of Na_(3)V_(2)(PO_(4))_(3) at low voltage,and then a new intercalation model was *** the transition from Na_(3)V_(2)(PO_(4))_(3) to Na_(4)V_(2)(PO_(4))_(3),Na ions insert into M1,M2 and M3 sites ***,during the transition of Na_(4)V_(2)(PO_(4))_(3)to Na_(5)V_(2)(PO_(4))_(3),Na ions mainly insert into M3 site.

关键词： Na_(3)V_(2)(PO_(4))_(3) Anode Low voltage NMR Sodium ion battery

Exploring the Spatiotemporal Changes and Driving Forces of Ecosystem Services of Zhejiang Coasts,China,Under Sustainable Development Goals

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Chinese Geographical Science 2024年第4期34卷 647-661页

作者： ZHANG Shu SUN Chao ZHANG Yixin HU ming shen Xingru Department of Geography and Spatial Information Techniques Ningbo UniversityNingbo 315211China Donghai Academy Ningbo UniversityNingbo 315211China Zhejiang Collaborative Innovation Center&Ningbo Universities Collaborative Innovation Center for Land and Marine Spatial Utilization and Governance Research Ningbo UniversityNingbo 315211China Xiangshan High School Ningbo 315700China

Ecosystem services(ESs)refer to the continuous provisioning of ecosystem goods and services that benefit human *** recent decades,rapid urbanization has exerted significant pressure on coastal ecosystems,resulting in biodiversity and habitat loss,environmental pollution,and the depletion of natural *** response to these environmental challenges,the Sustainable Development Goals(SDGs)were *** the pressing need to address these issues,understanding the changes in ESs under the SDGs is crucial for formulating specific ecological *** this study,we first analyzed land use and cover change in the Zhejiang coasts of China during 2000–***,we investigated the spatiotemporal configuration of ESs by integrating carbon storage(CS),soil retention(SR),habitat quality(HQ)and water yield(WY)using the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)*** driving mechanisms of ESs,which varied by space and time,were also explored using the Geo-detector *** results revealed that,over the past two decades:1)the Zhejiang coasts have experienced a significant increase of 2783.72 km^(2) in built-up land areas and a continuous decrease in farmland areas due to rapid urbanization;2)owing to higher precipitation,extensive vegetation cover,and reduced anthropogenic disturbances,forests emerge as a crucial land use type for maintaining ecosystem services such as HQ,CS,WY,and SR;3)ESs have generally declined across the entire Zhejiang coasts,with a significant decrease observed in the northern areas and an increase in the southern areas spatially;4)the expansion of built-up land areas emerged as the primary factor affecting ecosystem services,while the vegetation factor has been increasingly significant and is expected to become predominant in the near *** study provides insights of understanding of ecosystem service theory and emphasizing the importance of preserving biodiversity for long-term sustainable development

关键词： ecosystem services(ESs) Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model Geo-detector land use and cover change(LUCC) Zhejiang coasts China

Local Torrential Rainfall Event within a Mei-Yu Season Mesoscale Convective System:Importance of Back-Building Processes

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Advances in Atmospheric Sciences 2024年第5期41卷 847-863页

作者： Honglei ZHANG ming XUE Hangfeng shen Xiaofan LI Guoqing ZHAI Zhejiang Institute of Meteorological Sciences Hangzhou 310017China Center for Analysis and Prediction of Storms and School of MeteorologyUniversity of OklahomaNormanOklahoma 73072USA Department of Atmospheric Science School of Earth SciencesZhejiang UniversityHangzhou 310027China Hangzhou Weather Bureau Hangzhou 310007China

An extreme rainfall event occurred over Hangzhou,China,during the afternoon hours on 24 June *** event occurred under suitable synoptic conditions and the maximum 4-h cumulative rainfall amount was over 150 *** rainfall event had two major *** was caused by a quasi-stationary convective line,and the other by a backbuilding convective line related to the interaction of the outflow boundary from the first rainband and an existing low-level mesoscale convergence line associated with a mei-yu frontal *** rainfall event lasted 4 h,while the back-building process occurred in 2 h when the extreme rainfall center *** far,few studies have examined the back-building processes in the mei-yu season that are caused by the interaction of a mesoscale convergence line and a convective cold *** two rainbands are successfully reproduced by the Weather Research and Forecasting(WRF)model with fourlevel,two-way interactive *** the model,new cells repeatedly occur at the west side of older cells,and the backbuilding process occurs in an environment with large CAPE,a low LFC,and plenty of water *** from older cells enhance the low-level convergence that forces new *** precipitation efficiency of the back-building training cells leads to accumulated precipitation of over 150 *** experiments without evaporation of rainwater show that the convective cold pool plays an important role in the organization of the back-building process in the current extreme precipitation case.

关键词： torrential rainfall back-building processes numerical simulation trigger mechanism convergence line convective cold pool

Quantum support vector machine for multi classification

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Communications in Theoretical Physics 2024年第7期76卷 57-62页

作者： Li Xu Xiao-yu Zhang ming Li Shu-qian shen College of Science China University of PetroleumQingdao 266580China

Classical machine learning algorithms seem to be totally incapable of processing tremendous data,while quantum machine learning algorithms could deal with big data unhurriedly and provide exponential acceleration over classical *** this paper,we propose two quantum support vector machine algorithms for multi *** is the quantum version of the directed acyclic graph support vector *** other one is to use the Grover search algorithm before measurement,which amplifies the amplitude of the phase storing of the classification *** k classification,the former provides quadratic reduction in computational complexity when *** latter accelerates the training speed significantly and more importantly,the classification result can be read out with a probability of at least 50%using only one *** conduct numerical simulations on two algorithms,and their classification success rates are 96%and 88.7%,respectively.

关键词： quantum support vector machine quantum feature mapping Grover search algorithm

Recovery and in-situ reduction of precious metals by graphdiyne and graphdiyne oxide for antibacterial use

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Rare Metals 2024年第4期43卷 1747-1757页

作者： ming-Ji Jiang Ya-Na Zhang Ling-shen Meng Jing Kang Yong-Jun Li Alideertu Dong College of Chemistry and Chemical Engineering Inner Mongolia UniversityHohhot010021China Engineering Research Center of Dairy Quality and Safety Control Technology Ministry of EducationInner Mongolia UniversityHohhot010021China Department of Chemistry University of ZurichCH-8057ZurichSwitzerland Laboratory of Organic Solids and Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing100190China

Based on the in-situ self-reduction and chemical stability,graphdiyne(GDY)and graphdiyne oxide(GDYO)are used as trapping agents to investigate the ability for recovering Au^(3+),Ag^+,and Pd^(2+)under different pH values and interfering *** strong acidity at pH=1,these two agents demonstrate high select recovery towards the three precious metal ions,which could be insitu reduced to nanoparticles(NPs).In addition,superparamagnetic Fe_(3)O_(4)NPs are deposited on the surfaces of GDY and *** magnetic responses enable GDYFe_(3)O_(4)to recover precious metals conveniently and efficiently by the aid of an external magnetic *** study also confirms the antibacterial activity of the as-recovered NPs deposited on GDY and GDYO against Escherichia coli and Staphylococcus aureus(1×10^(5)colony-forming unit(CFU)·mL^(-1)),and the antibacterial rates are 100%.This strategy of recovering precious metals and subsequently reusing to combat pathogens will be of great significance for environmental remediation and biomedical applications.

关键词： Graphdiyne In-situ reduction Recovery Precious metals Antibacterial

Microphysical Characteristics of Rainfall Based on Long-Term Observations with a 2DVD in Yangbajain,Tibet

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Advances in Atmospheric Sciences 2024年第9期41卷 1721-1734页

作者： ming LI Yongheng BI Yonghai shen Yinan WANG Ciren Nima Tianlu CHEN Daren LYU Key Laboratory for Cosmic Rays of the Ministry of Education Tibet UniversityLhasa 850000China Key Laboratory of Middle Atmosphere and Global Environment Observation(LAGEO) Institute of Atmospheric PhysicsChinese Academy of ScienceBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Raindrop size distribution(DSD)plays a crucial role in enhancing the accuracy of radar quantitative precipitation estimates in the Tibetan Plateau(TP).However,there is a notable scarcity of long-term,high-resolution observations in this *** address this issue,long-term observations from a two-dimensional video disdrometer(2DVD)were leveraged to refine the radar and satellite-based algorithms for quantifying precipitation in the hinterland of the *** was observed that weak precipitation(R1,mm h-1)accounts for 86%of the total precipitation time,while small raindrops(D<2 mm)comprise 99%of the total raindrop ***,the average spectral width of the DSD increases with increasing rain *** DSD characteristics of convective and stratiform precipitation were discussed across five different rain rates,revealing that convective precipitation in Yangbajain(YBJ)exhibits characteristics similar to maritime-like *** constrained relationships between the slopeΛand shapeμ,D_(m)and N_(w)of gamma DSDs were ***,we established a correlation between the equivalent diameter and drop axis ratio and found that raindrops on the TP attain a nearly spherical ***,the application of the rainfall retrieval algorithms of the dual-frequency precipitation radar in the TP is improved based on the statistical results of the DSD.

关键词： Tibetan Plateau raindrop size distribution 2DVD dual frequency radar microphysical features