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defence Technology（防务技术） 2024年第7期37卷 1-13页

作者： Guangbo Xu Bingting Zha Hailu Yuan Zhen zheng He zhang Ministerial Key Laboratory of ZNDY Nanjing University of Science and TechnologyNanjing 210094China Science and Technology on Electromechanical Dynamic Control Laboratory Beijing 100081China Shanghai Radio Equipment Research Institute Shanghai 201109China

The phenomenon of a target echo peak overlapping with the backscattered echo peak significantly undermines the detection range and precision of underwater laser *** overcome this issue,we propose a four-quadrant dual-beam circumferential scanning laser fuze to distinguish various interference signals and provide more real-time data for the backscatter filtering *** enhances the algorithm loading capability of the *** order to address the problem of insufficient filtering capacity in existing linear backscatter filtering algorithms,we develop a nonlinear backscattering adaptive filter based on the spline adaptive filter least mean square(SAF-LMS)*** also designed an algorithm pause module to retain the original trend of the target echo peak,improving the time discrimination accuracy and anti-interference capability of the ***,experiments are conducted with varying signal-to-noise ratios of the original underwater target echo *** experimental results show that the average signal-to-noise ratio before and after filtering can be improved by more than31 d B,with an increase of up to 76%in extreme detection distance.

关键词： Laser fuze Underwater laser detection Backscatter adaptive filter Spline least mean square algorithm Nonlinear filtering algorithm

Numerical simulation of transient characteristics in a bulb turbine during the load rejection process

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Journal of Hydrodynamics 2024年第1期36卷 170-183页

作者： Yue Lu Yu-quan zhang Zhong-wei He Yuan zheng College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China College of Energy and Electrical Engineering Hohai UniversityNanjing210098China Huadong Engineering Corporation Ltd. Hangzhou311122China

To evaluate the safety of the bulb tubular turbine,the dynamic hydraulic characteristics of a hydropower station system during the load rejection process are studied through numerical simulations and a prototype *** the developed model,a dynamic grid technology(DGT)controls the closure of the guide vane and the blade,whilst the moment balance equation and the user-defined function(UDF)provide the runner’s rotation *** 3-D transient simulation method can well predict the rotation speed and mass flow curves in the state of load *** simulation outcomes of the system performance are basically consistent with the measurement data of the *** observed,the runner is subjected to the reversely increased torque and axial force,the system is in a braking phase,and the maximum speed peaks at 144.6%of the rated ***,the internal flow of the runner is greatly affected by the closure of the guide vane,and the draft tube forms an eccentric spiral vortex *** breaks downstream,aggravating the instability of the draft ***,the transient characteristics span for the first five seconds,demonstrating the importance of establishing an efficient governing *** obtained results are useful for designing the turbine’s flow channel with a double regulating function and comprehending the turbine’s transient characteristics.

关键词： Bulb tubular turbine load rejection numerical simulation dynamic grid prototype test

12.6μm-Thick Asymmetric Composite Electrolyte with Superior Interfacial Stability for Solid-State Lithium-Metal Batteries

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Nano-Micro Letters 2024年第9期16卷 397-409页

作者： zheng zhang Jingren Gou Kaixuan Cui Xin zhang Yujian Yao Suqing Wang Haihui Wang Beijing Key Laboratory for Membrane Materials and Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084People’s Republic of China School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou 510000People’s Republic of China

Solid-state lithium metal batteries(SSLMBs)show great promise in terms of high-energy-density and high-safety ***,there is an urgent need to address the compatibility of electrolytes with high-voltage cathodes/Li anodes,and to minimize the electrolyte thickness to achieve highenergy-density of ***,we develop an ultrathin(12.6μm)asymmetric composite solid-state electrolyte with ultralight areal density(1.69 mg cm^(−2))for *** electrolyte combining a garnet(LLZO)layer and a metal organic framework(MOF)layer,which are fabricated on both sides of the polyethylene(PE)separator separately by tape *** PE separator endows the electrolyte with flexibility and excellent mechanical *** LLZO layer on the cathode side ensures high chemical stability at high *** MOF layer on the anode side achieves a stable electric field and uniform Li flux,thus promoting uniform Li^(+)*** to the well-designed structure,the Li symmetric battery exhibits an ultralong cycle life(5000 h),and high-voltage SSLMBs achieve stable cycle *** assembled pouch cells provided a gravimetric/volume energy density of 344.0 Wh kg^(−1)/773.1 Wh L^(−1).This simple operation allows for large-scale preparation,and the design concept of ultrathin asymmetric structure also reveals the future development direction of SSLMBs.

关键词： Solid-state lithium metal batteries Composite solid-state electrolyte Ultrathin asymmetric structure Pouch cells

Efficient and reversible separation of NH_(3) by deep eutectic solvents with multiple active sites and low viscosities

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Chinese Journal of Chemical Engineering 2024年第3期67卷 97-105页

作者： Jiayin zhang Lu zheng Siqi Fang Hongwei zhang Zhenping Cai Kuan Huang Lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst(NERC-CFC) College of Chemical EngineeringFuzhou UniversityFuzhou 350002China Qingyuan Innovation Laboratory Quanzhou 362801China

The efficient separation and collection of ammonia(NH_(3))during NH_(3) synthesis process is essential to improve the economic efficiency and protect the *** this work,ethanolammonium hydrochloride(EtOHACl)and phenol(PhOH)were used to prepare a novel class of deep eutectic solvents(deSs)with multiple active sites and low *** NH_(3) separation performance of EtOHACl+PhOH deSs was analyzed *** is figured out that the NH_(3) absorption rates in EtOHACl+PhOH deSs are very *** NH_(3) absorption capacities are very high and reach up to 5.52 and 10.74 mol·kg1 at 11.2 and 100.4 kPa under 298.2 K,*** addition,the EtOHACl+PhOH deSs present highly selective absorption of NH_(3) over N_(2) and H_(2) and good regenerative properties after seven cycles of absorption/*** intrinsic separation mechanism of NH_(3) by EtOHACl+PhOH deSs was further revealed by spectroscopic analysis and quantum chemistry calculations.

关键词： Separation Absorption Ionic liquid deep eutectic solvent Multiple active site Low viscosity

Mechanism of acupuncture in attenuating cerebral ischaemia-reperfusion injury based on nuclear receptor coactivator 4 mediated ferritinophagy

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Journal of Traditional Chinese Medicine 2024年第2期44卷 345-352页

作者： zhang Xinchang HUANG zheng HUANG Peiyan YANG Mengning zhang Zhihui NI Guangxia College of Acupuncture-Moxibustion and Tuina Nanjing University of Chinese MedicineNanjing 210023China Key Laboratory of Acupuncture and Medicine Research of Ministry of Education Nanjing University of Chinese MedicineNanjing 210023China

OBJECTIVE:To explore the effect of acupuncture treatment on cerebral ischaemia-reperfusion injury(CIRI)and reveal the underlying mechanism of the effect based on nuclear receptor coactivator 4(NCOA4)mediated ***:Sprague-Dawley male rats were divided into four groups:the sham group,model group,acupuncture group,and sham acupuncture *** 2 h of middle cerebral artery occlusion(MCAO),reperfusion was performed for 24 h to induce *** rats were treated with acupuncture at the Neiguan(PC6)and Shuigou(GV26)*** neurological function was evaluated by taking their Bederson scores at 2 h after ischaemia and 24 h after *** chloride staining was applied to assess the cerebral infarct volume at 24 h after *** malondialdehyde(MDA)and ferrous iron(Fe^(2+))levels were observed after 24 h of reperfusion using an assay *** blotting was performed to detect the expression of NCOA4 and ferritin heavy chain 1(FTH1)at 24 h after ***,the colocalization of ferritin with neurons,NCOA4 with microtubule-associated protein 1 light chain 3(LC3),and NCOA4 with ferritin was visualized using immunofluorescence ***:Acupuncture significantly improved neurological function and decreased cerebral infarct volume in the acupuncture *** CIRI,the expression of NCOA4,LC3 and FTH1 was increased,which enhanced ferritinophagy and induced an inappropriate accumulation of Fe^(2+)and MDA in the ischaemic ***,acupuncture dramatically downregulated the expression of NCOA4,LC3 and FTH1,inhibited the overactivation of ferritinophagy,and decreased the levels of MDA and Fe^(2+).CONCLUSIONS:Acupuncture can inhibit NCOA4-mediated ferritinophagy and protect neurons against CIRI in a rat model.

关键词： acupuncture ferritinophagy ferroptosis ferritin nuclear receptor coactivator 4 cerebral ischaemia-reperfusion injury

Molecular regulation of the key specialized metabolism pathways in medicinal plants

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Journal of Integrative Plant Biology 2024年第3期66卷 510-531页

作者： Min Shi Siwei zhang Zizhen zheng Itay Maoz Lei zhang Guoyin Kai Zhejiang Provincial International S&T Cooperation Base for Active Ingredients of Medicinal and Edible Plants and Health Zhejiang Provincial Key TCM Laboratory for Chinese Resource Innovation and TransformationSchool of Pharmaceutical SciencesJinhua AcademyZhejiang Chinese Medical UniversityHangzhou 310053China department of Postharvest Science Agricultural Research OrganizationVolcani CenterRishonLeZion 7505101Israel department of Pharmaceutical Botany School of PharmacyNaval Medical UniversityShanghai 200433China

The basis of modern pharmacology is the human ability to exploit the production of specialized metabolites from medical plants,for example,terpenoids,alkaloids,and phenolic ***,in most cases,the availability of these valuable compounds is limited by cellular or organelle barriers or spatio-temporal accumulation patterns within different plant *** factors(TFs)regulate biosynthesis of these specialized metabolites by tightly controlling the expression of biosynthetic ***-edge technologies and/or combining multiple strategies and approaches have been applied to elucidate the role of *** this review,we focus on recent progress in the transcription regulation mechanism of representative high-value products and describe the transcriptional regulatory network,and future perspectives are discussed,which will help develop high-yield plant resources.

关键词： biosynthesis medicinal plants omics secondary metabolism transcription factors

Special issue on electrochemical conversion and utilization of hydrogen energy

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Frontiers in Energy 2024年第3期18卷 263-264页

作者： Yun zheng Bo YU Xiaogang FU Jiujun zhang Institute of New Energy Materials and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China State Key Laboratory of Solidification Processing Atomic Control&Catalysis Engineering LaboratorySchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China

The concerns over energy crisis and climate change caused by the excessive consumption of fossil fuels and the associated emission of greenhouse gases, have driven many countries to develop policies for an energy transition into zero-carbon energy sources, essentially aiming at decarbonizing their energy systems. Among various renewable sources, hydrogen has been hailed as an ideal alternative to provide secure, cost-effective, and non-polluting energy. In recent years, there has been noteworthy progress in hydrogen electrochemical conversion and utilization techniques and devices, including water electrolyzers, proton-exchange membrane fuel cells (PEMFCs), solid oxide fuel cells (SOFCs), etc. Each of these technologies has yielded a series of encouraging advances. To showcase these recent advances, Frontiers in Energy is launching a special issue titled “electrochemical conversion and utilization of hydrogen energy”.

关键词： hydrogen energy. electrochemical

A new scheme of climate-vegetation regionalization in the Hengduan Mountains Region

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Science China Earth Sciences 2024年第3期67卷 751-768页

作者： Xueqin zhang Xiaoming XU Xiang LI Peng CUI Du zheng Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China China-Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences-Higher Education Commission of PakistanIslamabad 45320Pakistan

The Hengduan Mountains Region(HMR) is essential for the future ecological protection, clean energy production,Sichuan-Xizang and Yunnan-Xizang railways, and other major infrastructure projects in China. The distributions of climate and vegetation exhibit significant regional differentiation and vertical zonality due to the rugged longitudinal ranges and gorges and the complex disaster-prone environments in HMR. Therefore, it is urgent to develop the climate-vegetation regionalization in HMR to effectively satisfy the national requirements such as agricultural production and ecological protection, mountain disaster risk prevention, and major project construction. We here develop a new scheme of climate-vegetation regionalization with the latest demarcation outcome of HMR, the ground observation from 122 meteorological stations in HMR and its surrounding areas during 1990–2019, and the high-precision remote sensing data of land cover types. The new scheme first constructs the regionalization index system, fully considering the extraordinarily complicated geomorphic pattern of mountains and valleys, the scarcity of meteorological observations, and the remarkable differentiation of climate and vegetation in HMR. The system consists of three primary regionalization indices(i.e., days with daily average temperature steady above 10°C, aridity index, and main vegetation types, dividing the temperature zones, moisture regions, and vegetation subregions, respectively) and three auxiliary indices of the accumulated temperature above 10°C, and the temperatures in January and July. Then, the HMR is divided into five temperature zones, 20 moisture regions, and 55 vegetation subregions. Compared with previous regionalization schemes, the new scheme optimizes the climate spatial interpolation model of thin plate smoothing spline suitable for the unique terrain in HMR. Moreover, the disputed division index threshold between different climatic zones(regions) is scientifically clarifi

关键词： Climate-vegetation regionalization Thin plate smoothing spline(TPSS) Geodetector Stepwise downscaling pane division method Hengduan Mountains Region

Variational quantum algorithms for scanning the complex spectrum of non-Hermitian systems

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Frontiers of physics 2024年第4期19卷 275-285页

作者： Xu-Dan Xie zheng-Yuan Xue Dan-Bo zhang Key Laboratory of Atomic and Subatomic Structure and Quantum Control(Ministry of Education) Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matterand School of PhysicsSouth China Normal UniversityGuangzhou 510006China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials Guangdong–Hong Kong Joint Laboratory of Quantum Matterand Frontier Research Institute for PhysicsSouth China Normal UniversityGuangzhou 510006China

Solving non-Hermitian quantum many-body systems on a quantum computer by minimizing the variational energy is challenging as the energy can be ***,we propose a variational quantum algorithm for solving the non-Hermitian Hamiltonian by minimizing a type of energy variance,where zero variance can naturally determine the eigenvalues and the associated left and right ***,the energy is set as a parameter in the cost function and can be tuned to scan the whole spectrum efficiently by using a two-step optimization *** numerical simulations,we demonstrate the algorithm for preparing the left and right eigenstates,verifying the biorthogonal relations,as well as evaluating the *** also investigate the impact of quantum noise on our algorithm and show that its performance can be largely improved using error mitigation ***,our work suggests an avenue for solving non-Hermitian quantum many-body systems with variational quantum algorithms on near-term noisy quantum computers.

关键词： quantum algorithm non-Hermitian physics quantum manybody systems

Magnetism of NaYbS_(2):From finite temperatures to ground state

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 92-104页

作者： Weizhen Zhuo zheng zhang Mingtai Xie Anmin zhang Jianting Ji Feng Jin Qingming zhang School of Physical Science and Technology Lanzhou UniversityLanzhou 730000China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

Rare-earth chalcogenide compounds ARECh_(2)(A=alkali or monovalent metal,RE=rare earth,Ch=O,S,Se,Te)are a large family of quantum spin liquid(QSL)candidate ***2is a representative member of the *** key issues on NaYbS_(2),particularly how to determine the highly anisotropic spin Hamiltonian and describe the magnetism at finite temperatures and the ground state,remain to be *** this paper,we conducted an in-depth and comprehensive study on the magnetism of NaYbS_(2) from finite temperatures to the ground ***,we successfully detected three crystalline electric field(CEF)excitation energy levels using low-temperature Raman scattering *** them with the CEF theory and magnetization data,we worked out the CEF parameters,CEF energy levels,and CEF *** further determined a characteristic temperature of~40 K,above which the magnetism is dominated by CEF excitations while below which the spinexchange interactions play a main *** characteristic temperature has been confirmed by the temperature-dependent electron spin resonance(ESR)***-temperature ESR experiments on the dilute magnetic doped crystal of NaYb_(0.1)Lu_(0.9)S_(2) further helped us to determine the accurate ***,we quantitatively obtained the spin-exchange interactions in the spin Hamiltonian by consistently simulating the magnetization and specific heat ***,the above studies allow us to explore the ground state magnetism of NaYbS_(2) by using the density matrix renormalization *** combined numerical calculations and experimental results to demonstrate that the ground state of NaYbS_(2) is a Dirac-like QSL.

关键词： rare-earth chalcogenide anisotropic spin Hamiltonian quantum spin liquid