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The pseudospectrum and spectrum(in)stability of quantum corrected Schwarzschild black hole

Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 55-75页

作者： Li-Ming Cao Jia-Ning Chen Liang-bi Wu Libo Xie Yu-Sen Zhou School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China Peng Huanwu Center for Fundamental Theory Hefei 230026China Interdisciplinary Center for Theoretical Study and Department of Modern Physics University of Science and Technology of ChinaHefei 230026China

In this study,we investigate the pseudospectrum and spectrum(in)stability of quantum corrected Schwarzschild black ***,we use the hyperboloidal framework to cast the quasinormal mode(QNM)problem into an eigenvalue problem associated with a non-selfadjoint operator,and then the spectrum and pseudospectrum are ***,the invariant subspace method is exploited to improve the computational efficiency for *** investigation into the spectrum(in)stability entails two main *** the one hand,we calculate the spectra of the quantum corrected black hole,then by the means of the migration ratio,the impact of the quantum correction effect on the Schwarzschild black hole has been *** results indicate that the so-called“migration ratio instability”will occur for small black holes with small angular momentum number *** the eikonal limit,the migration ratios remain the same for each *** the other hand,we study the spectrum(in)stability of the quantum corrected black hole by directly adding some particular perturbations into the effective potential,where perturbations are located at the event horizon and null infinity,*** are two interesting observations under the same perturbation energy ***,perturbations at infinity are more capable of generating spectrum instability than those at the event ***,we find that the peak distribution can lead to the instability of QNM spectrum more efficiently than the average distribution.

关键词： quasinormal modes pseudospectrum hyperboloidal coordinate

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Computational Experiments for Complex Social Systems:Integrated Design of Experiment System

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1175-1189页

作者： Xiao Xue Xiangning Yu Deyu Zhou Xiao Wang Chongke bi Shufang Wang Fei-Yue Wang College of Intelligence and Computing Tianjin UniversityTianjin 300350China School of Software Shandong UniversityJinan 250101China School of Artificial Intelligence Anhui UniversityHefei 230601China School of Geographic and Environmental Sciences Tianjin Normal UniversityTianjin 300387China Institute of Automation Chinese Academy of Sciences Beijing 100190China

Powered by advanced information industry and intelligent technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).And human factors have become crucial in the operations of complex social *** mechanical analysis and social simulations alone are powerless for analyzing complex social *** this backdrop,computational experiments have emerged as a new method for quantitative analysis of complex social systems by combining social simulation(e.g.,ABM),complexity science,and domain ***,in the process of applying computational experiments,the construction of experiment system not only considers a large number of artificial society models,but also involves a large amount of data and *** a result,how to integrate various data,model and knowledge to achieve a running experiment system has become a key *** paper proposes an integrated design framework of computational experiment system,which is composed of four parts:generation of digital subject,generation of digital object,design of operation engine,and construction of experiment ***,this paper outlines a typical case study of coal mine emergency management to verify the validity of the proposed framework.

关键词： artificial system operations

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Spark Plasma Sintering of Boron Carbide Using Ti_(3)SiC_(2) as a Sintering Additive

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 645-650页

作者： Hülya biçer Mustafa Tuncer Hasan Göçmez Iurii Bogomol Valerii Kolesnichenko Andrey Ragulya Kutahya Dumlupinar University School of EngineeringDepartment of Metallurgical and Materials EngineeringKütahya 43100Tur-key Boron Based Advanced Ceramics Application and Research Center Kütahya Dumlupınar UniversityKütahya 43100Turkey Advanced Technologies Center(İLTEM) Kütahya Dumlupınar UniversityKütahya 43000Turkey Department of High-Temperature Ma-terials and Powder Metallurgy National Technical University of Ukraine“Igor Sikorsky Kyiv Polytechnic Institute”Kyiv 03056Ukraine Frantsevich Institute for Problems of Materials Science National Academy of Sciences of UkraineKyiv 03056Ukraine

Boron carbide has unique properties for wide application possibilities;however,poor sinterability limits its *** approach to overcome this limitation is the addition of secondary phases into boron *** carbide based composite ceramics are produced by the direct addition of secondary phases into the structure or via reactive sintering using a sintering *** present study investigated the effect of Ti_(3)SiC_(2) addition to boron carbide by reactive spark plasma sintering in the range of 1700-1900℃.Ti_(3)SiC_(2) phase decomposed at high temperatures and reacted with B4C to form secondary phases of TiB2 and *** results demonstrated that the increase of Ti_(3)SiC_(2) addition(up to 15 vol%)effectively promoted the densification of B4C and yielded higher ***,as the amount of Ti_(3)SiC_(2) increased further,the formation of microstructural inhomogeneity and agglomeration of secondary phases caused a decrease in hardness.

关键词： reactive sintering SPS boron carbide MAX phase

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Boosting spring runoff into the sea by reservoir regulation and its potential for estuarine fishery recovery

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Science China Earth Sciences 2024年第5期67卷 1591-1603页

作者： Xiao WU Houjie WANG Yongyong FAN Naishuang bi Chiyuan MIAO Jingping XU Zuosheng YANG College of Marine Geosciences Key Laboratory of Submarine Geosciences and Prospecting Technologyand Frontiers Science Center for Deep Ocean Multispheres and Earth SystemOcean University of ChinaQingdao 266100China Laoshan National Laboratory Qingdao 266061China Institute of the Yellow River Estuary and Coast Science Dongying 257000China State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Department of Ocean Science&Engineering Southern University of Science and TechnologyShenzhen 518055China

With global surge in reservoir construction over the past decades,river systems worldwide have been profoundly ***,flow manipulation by reservoirs has altered the natural hydrological processes,resulting in extensive modifications of fluvial-marine *** the adverse ecological consequences of reservoirs has become a global concern and has garnered increasing *** Yellow River,as one of the most extensively manipulated river systems globally,has experienced substantial changes in the amount and timing of water discharge due to the presence of numerous reservoirs scattered throughout its catchment *** alterations have caused physicochemical changes in the estuary and subsequent modifications to the estuarine *** recent years,the Yellow River Conservancy Committee initiated the release of water through the Xiaolangdi Dam during the major spawning period of fisheries,specifically in the spring,with the aim of improving the estuarine ecological *** 2011 to 2020,a total of 84.05 km^(3)of water was discharged from the Xiaolangdi Reservoir during spring seasons,of which 40%(33.16 km^(3))constituted water impounded within the reservoir during preceding ***,the spring water discharge from the Yellow River to the sea increased significantly from 1.50 km^(3)/yr to 3.46 km^(3)/yr in the past decade,leading to a decrease in estuarine salinity by 1.6 *** estuarine fishery resources,such as fish eggs in the Yellow River estuary,have demonstrated evident *** reservoir regulation in the Yellow River,which has successfully enhanced spring water discharge and subsequently restored estuarine fishery resources,presents an effective attempt for mitigating the adverse ecological effects associated with reservoirs.

关键词： Reservoir regulation Water release Spring runoff Estuarine ecosystem Yellow River

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Mechanism and application of feedback loops formed by mechanotransduction and histone modifications

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Genes & Diseases 2024年第5期11卷 198-218页

作者： Han Sun Yafang Gao Xinyu Ma Yizhou Deng Lintao bi Lisha Li Department of Hematology and Oncology China-Japan Union HospitalJilin UniversityChangchunJilin 130021China The Key Laboratory of Pathobiology Ministry of EducationCollege of Basic Medical SciencesJilin UniversityChangchunJilin 130021China

Mechanical stimulation is the key physical factor in cell *** acts as a fundamental regulator of cell behavior,regulating cell proliferation,differentiation,apoptosis,and exhibiting specific signature alterations during the pathological *** research continues,the role of epigenetic science in mechanotransduction is attracting ***,the molecular mechanism of the synergistic effect between mechanotransduction and epigenetics in physiological and pathological processes has not been *** focus on how histone modifications,as important components of epigenetics,are coordinated with multiple signaling pathways to control cell fate and disease ***,we propose that histone modifications can form regulatory feedback loops with signaling pathways,that is,histone modifications can not only serve as downstream regulators of signaling pathways for target gene transcription but also provide feedback to regulate signaling *** and epigenetic changes could be potential markers and therapeutic targets in clinical practice.

关键词： FAK Histone modifications MAPK Mechanotransduction RhoA WNT/b-catenin YAP/TAZ

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Transfer-free chemical vapor deposition graphene for nitride epitaxy: challenges, current status and future outlook

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Science China Chemistry 2024年第3期67卷 824-840页

作者： Xiang Gao Senlin Li Jingfeng bi Kaixuan Zhou Meng Li Zhongfan Liu Jingyu Sun College of Energy Soochow Institute for Energy and Materials InnovationsSUDA-BGI Collaborative Innovation CenterKey Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu ProvinceSoochow UniversitySuzhou 215006China Beijing Graphene Institute Beijing 100095China Xiamen Silan Advanced Compound Semiconductor Co.Ltd. Xiamen 361026China

Graphene, a two-dimensional material with outstanding electrical and mechanical properties, has attracted considerable attention in the field of semiconductor technologies due to its potential use as a buffer layer for the epitaxial Ⅲ-nitride growth. In recent years, significant progress has been made in the chemical vapor deposition growth of graphene on various insulating substrates for the nitride epitaxy, which offers a facile, inexpensive, and easily scalable methodology. However, certain challenges are still present in the form of producing high-quality graphene and achieving optimal interface compatibility with Ⅲ-nitride *** this review, we provide an overview of the bottlenecks associated with the transferred graphene fabrication techniques and the state-of-the-art techniques for the transfer-free graphene growth. The present contribution highlights the current progress in the transfer-free graphene growth on different insulating substrates, including sapphire, quartz, SiO_(2)/Si, and discusses the potential applications of transfer-free graphene in the Ⅲ-nitride epitaxy. Finally, it includes the prospects of the transfer-free graphene growth for the Ⅲ-nitride epitaxy and the challenges that should be overcome to realize its full potential in this field.

关键词： Transfer-free chemical vapor deposition graphene for nitride epitaxy challenges current status and future outlook graphene

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Development of SV2A Ligands for Epilepsy Treatment:A Review of Levetiracetam,Brivaracetam,and Padsevonil

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Neuroscience Bulletin 2024年第5期40卷 594-608页

作者： Peng-Peng Wu bi-Rong Cao Fu-Yun Tian Zhao-bing Gao Center for Neurological and Psychiatric Research and Drug Discovery Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai201203China University of Chinese Academy of Sciences Beijing100049China Zhongshan Institute for Drug Discovery Shanghai Institute of Materia MedicaChinese Academy of SciencesZhongshan528400China

Epilepsy is a common neurological disorder that is primarily treated with antiseizure medications(ASMs).Although dozens of ASMs are available in the clinic,approximately 30%of epileptic patients have medically refractory seizures;other limitations in most traditional ASMs include poor tolerability and drug-drug ***,there is an urgent need to develop alternative ***(LEV)is a first-line ASM that is well tolerated,has promising efficacy,and has little drug-drug *** it is widely accepted that LEV acts through a unique therapeutic target synaptic vesicle protein(SV)2A,the molecular basis of its action remains *** so,the next-generation SV2A ligands against epilepsy based on the structure of LEV have achieved clinical *** review highlights the research and development(R&D)process of LEV and its analogs,brivaracetam and padsevonil,to provide ideas and experience for the R&D of novel ASMs.

关键词： Levetiracetam Epilepsy Antiseizure medications Synaptic vesicle protein 2A Brivaracetam Padsevonil

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Functional properties of defatted chickpea flour heat-induced gels

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International Journal of Agricultural and biological Engineering 2024年第2期17卷 280-286页

作者： Chonghao bi Aoxue Qie Tong Zhou Yi Liu bin Tian School of Artificial Intelligence Beijing Technology and Business UniversityBeijing 100048China

Defatted chickpea flour(DCF),which is a by-product of chickpea oil extraction industry,is rich in nutrients that are beneficial to human *** this study,the effects of temperature and DCF variation on the rheological properties,water holding capacity,freeze-thaw stability and microstructure of DCF heat induced gels were *** results showed that the viscoelasticity,frequency dependence,and resistance strength of heat induced gels increased significantly with the increase of temperature and DCF *** degree of denaturation and water retention of heat induced gels increased significantly with increased variables within the temperature and variation windows of 75℃ to 95℃ and 13%to 21%.The CLSM results revealed that variations of both temperature and DCF variation could cause the proteins in the heat induced gels to aggregate gradually and to form protein *** temperature or variation exceeded certain value(85℃ or 17%),the protein aggregations broke up and the protein clusters became smaller and more ***,the heat induced gels presented better water holding capacity,viscoelasticity,structural stability and gel property at a temperature of 95℃ or a DCF variation of 21%within the present experimental range.

关键词： defatted chickpea flour rheological property freeze-thaw stability water holding capacity microstructure

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合金成分对GH4099合金激光选区熔化成形组织及性能的影响

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粉末冶金工业 2023年第6期33卷 45-52页

作者：楚瑞坤张熹雯霍俊美彭世清毕中南张少明常州钢研极光增材制造有限公司江苏常州213100 钢铁研究总院有限公司北京100081 北京钢研高纳科技股份有限公司北京100081

通过激光选区熔化成形工艺制备不同成分的GH4099合金试样,研究不同合金成分对组织形貌及其力学性能的影响规律。结果表明,三组成分GH4099合金打印成形态组织均无明显的缺陷,但经固溶热处理后晶粒等轴化程度有所差异,主要是由于C、Cr、Mo... 详细信息

通过激光选区熔化成形工艺制备不同成分的GH4099合金试样,研究不同合金成分对组织形貌及其力学性能的影响规律。结果表明,三组成分GH4099合金打印成形态组织均无明显的缺陷,但经固溶热处理后晶粒等轴化程度有所差异,主要是由于C、Cr、Mo、W、Ti等碳化物形成元素差异促使GH4099合金中碳化物特征差异所致。各成分GH4099合金900℃拉伸强度和塑性具有明显的差异,与各合金等轴化程度及其组织中碳化物的分布位置和形态有明显关联,等轴状晶粒晶界非连续分布的碳化物与晶内弥散分布的细小颗粒状M23C6型碳化物有利于保持较高的强度和塑性;初始组织中较高含量的MC型碳化物沿晶界连续分布,钉扎晶界导致晶粒等轴化程度较低,展现强度高、塑性低的特点,断口形貌呈现沿原始柱状晶晶界断裂。Ti元素等促MC型碳化物形成元素对晶粒等轴化不利,同时沿晶界连续分布的MC型碳化物不利于900℃拉伸塑性,Cr、Mo、W等促M_(23)C_6型碳化物形成元素,虽对晶粒等轴化有所影响,但可通过固溶强化提高高温强度,在900℃保持较好的塑性。

关键词：选区激光熔化 GH4099 合金成分碳化物 900℃拉伸

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Virtual source approach for maximizing resolution in high-penetration gamma-ray imaging

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Matter and Radiation at Extremes 2024年第3期9卷 19-30页

作者： Yuchi Wu Shaoyi Wang bin Zhu Yonghong Yan Minghai Yu Gang Li Xiaohui Zhang Yue Yang Fang Tan Feng Lu bi bi Xiaoqin Mao Zhonghai Wang Zongqing Zhao Jingqin Su Weimin Zhou Yuqiu Gu National Key Laboratory of Plasma Physics Laser Fusion Research CenterCAEPMianyangSichuan 621900China College of Physics Sichuan UniversityChengdu 610065China

High-energy gamma-ray radiography has exceptional penetration ability and has become an indispensable nondestructive testing(NDT)tool in various *** high-energy photons,point projection radiography is almost the only feasible imaging method,and its spatial resolution is primarily constrained by the size of the gamma-ray *** conventional industrial applications,gamma-ray sources are commonly based on electron beams driven by accelerators,utilizing the process of bremsstrahlung *** size of the gamma-ray source is dependent on the dimensional characteristics of the electron *** research has been conducted on various advanced accelerator technologies that have the potential to greatly improve spatial resolution in *** our investigation of laser-driven gamma-ray sources,a spatial resolution of about 90μm is achieved when the areal density of the penetrated object is 120 g/cm^(2).A virtual source approach is proposed to optimize the size of the gamma-ray source used for imaging,with the aim of maximizing spatial *** this virtual source approach,the gamma ray can be considered as being emitted from a virtual source within the convertor,where the equivalent gamma-ray source size in imaging is much smaller than the actual emission *** the basis of Monte Carlo simulations,we derive a set of evaluation formulas for virtual source scale and gamma-ray emission *** optimal conditions,the virtual source size can be as small as 15μm,which can significantly improve the spatial resolution of high-penetration imaging to less than 50μm.

关键词： resolution approach utilizing

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