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Scattering model of Ce3+–doped high gadolinium fluoro–oxide glass in scintillation progress

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Ceramics International 2025年第17期51卷 23367-23373页

作者： Hua, Zhehao Li, Weichang Qian, Sen Tao, Haizheng Chen, Danping Cai, Hua Han, Jifeng Huang, Feng Jia, Jinsheng Qiao, Xvsheng Ren, Jing Sun, Xin-Yuan Tang, Gao Yin, Shenghua Yuan, Huiping Zhang, Minghui State Key Laboratory of Silicate Materials for Architectures Wuhan University of Technology Wuhan430070 China Institute of High Energy Physics Chinese Academy of Sciences Beijing100049 China China Building Materials Academy Beijing100024 China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai201800 China Key Lab of Radiation Physics and Technology of MOE Sichuan University Chengdu610065 China Key Laboratory of Rare Earths Ganjiang Innovation Academy Chinese Academy of Sciences Ganzhou341003 China State Key Laboratory of Silicon and Advanced Semiconductor Materials & Department of Materials Science and Engineering Zhejiang University Hangzhou310027 China College of Physics and Optoelectronic Engineering Harbin Engineering University Harbin150001 China Department of Physics and Key Laboratory of Jiangxi Province for Special Optoelectronic Artificial Crystal Materials Jinggangshan University Ji'an343009 China College of Materials and Chemistry China Jiliang University Hangzhou310018 China Nuclear Instrument CO. LTD. Beĳing100176 China Beijing Glass Research Institute Beijing101111 China Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai201899 China

High density Gd2O3–GdF3–Al2O3–B2O3–SiO2–CeF3 (GFOx) glass scintillators with different dimensions were synthesized. The glasses have a ∼75 % transmittance in visible range with a cut off wavelength of 373 nm. With the dimension increases, the energy transfer efficiency of GFOx glasses decreases from 77.0 % to 28.3 %. And the photoluminescence quantum yield (PL QY) of all glasses exceeds 56 % with a maximum of 68.4 %. GFOx glass scintillators exhibit a X–ray excitation luminescence (XEL) spectrum in 300–600 nm, and the XEL intensity decreases with increasing dimension. Under γ–ray excitation, a scattering model was established based on the light yield and aspect ratio of the glasses. The accuracy of the model was verified by measurement of commercial BGO crystal. In GFOx glass scintillator system, the intrinsic light yield of at 10 mm thickness is 1318 ph/MeV, while light loss coefficient is −0.12. With the aspect ratio increases, the formation and transport efficiency of excitons improve due to a larger surface area and more interfaces, resulting in a faster rise time. Meanwhile, all glasses exhibit a double exponential decay, including a fast component (∼100 ns) and a slow component (∼520 ns), and shows same trend as the rise time. In addition, the photon collection efficiency of SiPM coupled with the glasses decreased from 96.2 % to 31.8 %. Because the scattered photons can hardly reach the SiPM due to poor actual light attenuation length. © 2025

关键词： Aspect ratio

Exploring the effects of phase modulation on the dynamics of the kicked rotor systems

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Physical Review E 2022年第1期105卷 014212-014212页

作者： Mengyao Li Yingying Xiao Yongchun Tao Yi Gao Peiqing Tong Center for Quantum Transport and Thermal Energy Science Jiangsu Key Lab on Opto-Electronic Technology School of Physics and Technology Nanjing Normal University Nanjing 210023 China. School of Physics and Technology Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal University Nanjing 210023 China.

Inspired by the recent experimental progress in the time-driven phase transition in quantum chaos, we investigate comprehensively the energy diffusion of a kicked rotor in the presence of phase modulation. In the classical case, we found that there always exists anomalous diffusion as long as the phase is modulated periodically and changes by 0 or π from kick to kick. On the contrary, for quasiperiodic and random phase modulation, anomalous diffusion is suppressed. On the other hand, in the quantum case, there exist only ballistic energy diffusion and dynamical localization in the standard and periodically shifted cases, while random phase modulation destroys the quantum coherence and totally suppresses the dynamical localization. Furthermore, the quasiperiodic phase modulation is an intermediate phase between the standard case and the random one. In both the classical and quantum cases, quasiperiodic phase modulation is inequivalent to random phase modulation at large kicking times (>103), thus caution has to be taken when dealing with these two kinds of phase modulation in experiments.

关键词： Cold atoms & matter waves 1-dimensional systems

Impact of Black Swan Events on Ethereum Blockchain ERC20 Token Transaction Networks

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arXiv 2023年

作者： Pradeep, Moturi Dyapa, Uday Kumar Reddy Jalan, Sarika Pradhan, Priodyuti Department of Physics & Astrophysics University of Delhi India Department of Computer Science & Engineering Indian Institute of Information Technology Karnataka Raichur584135 India Complex Systems Lab Department of Physics Indian Institute of Technology Indore Khandwa Road Simrol Indore453552 India

The Ethereum blockchain and its ERC20 token standard have revolutionized the landscape of digital assets and decentralized applications. ERC20 tokens developed on the Ethereum blockchain have gained significant attention since their introduction. They are programmable and interoperable tokens, enabling various applications and token economies. Transaction graphs, representing the flow of the value between wallets within the Ethereum network, have played a crucial role in understanding the system’s dynamics, such as token transfers and the behavior of traders. Here, we explore the evolution of daily transaction graphs of ERC20 token transactions, which sheds light on the trader’s behavior during the Black Swan Events – 2018 crypto crash and the COVID-19 pandemic. By using the tools from network science and differential geometry, we analyze 0.98 billion of ERC20 token transaction data from November 2015 to January 2023. Our analysis reveals that ERC20 financial ecosystem has evolved from a localized wealth formation period to a more mature financial ecosystem where wealth has dispersed among the traders in the network after the crypto crash and during the pandemic period. Before the crash, most sellers only sell the tokens, and buyers only buy the tokens. However, after the crash and during the pandemic period, sellers and buyers both performed buying and selling activities. In addition, we observe no significant negative impact of the COVID-19 pandemic on user behavior in the financial ecosystem. © 2023, CC BY.

关键词： Blockchain

Reconstruction of Poloidal Magnetic Fluxes on EAST based on Neural Networks with Measured Signals

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arXiv 2024年

作者： Long, Feifei Xia, Xiangze Liu, Jian Liu, Zixi Wu, Xiaodong Wu, Xiaohe Wan, Chenguang Gao, Xiang Li, Guoqiang Luo, Zhengping Qian, Jinping Department of Plasma Physics and Fusion Engineering University of Science and Technology of China Hefei230031 China Advanced Algorithm Joint Lab National Supercomputing Center in Jinan Shandong Jinan250014 China

The accurate construction of tokamak equilibria, which is critical for the effective control and optimization of plasma configurations, depends on the precise distribution of magnetic fields and magnetic fluxes. Equilibrium fitting codes, such as EFIT relying on traditional equilibrium algorithms, require solving the Grad–Shafranov equation by iterations based on the least square method constrained with measured magnetic signals. The iterative methods face numerous challenges and complexities in the pursuit of equilibrium optimization. Furthermore, these methodologies heavily depend on the expertise and practical experience, demanding substantial resource allocation in personnel and time. This paper reconstructs magnetic equilibria for the EAST tokamak based on artificial neural networks through a supervised learning method. We use a fully connected neural network to replace the Grad-Shafranov equation and reconstruct the poloidal magnetic flux distribution by training the model based on EAST datasets. The training set, validation set, and testing set are partitioned randomly from the dataset of poloidal magnetic flux distributions of the EAST experiments in 2016 and 2017 years. The accuracy of reconstructions is evaluated using a variety of indices, such as the mean squared error (MSE), peak signal-to-noise ratio (PSNR), and structural similarity index measure (SSIM), and similarity (S) with Fréchet distance. The feasibility of the neural network model is verified by comparing it to the offline EFIT results. It is found that the neural network algorithm based on the supervised machine learning method can accurately predict the location of different closed magnetic flux surfaces at a high efficiency. The similarities of the predicted X-point position and last closed magnetic surface are both 98%. The Pearson coherence of the predicted q profiles is 92%. Compared with the target value, the model results show the potential of the neural network model for practical use

关键词： Iterative methods

Moiré pattern assisted geometric resonant tunneling in disordered twisted bilayer graphene

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arXiv 2023年

作者： Hou, Zhe Hu, Ya-Yun Yang, Guang-Wen Research Center for Intelligent Supercomputing Zhejiang Lab Hangzhou311100 China School of Physics and Technology Nanjing Normal University Nanjing210023 China Department of Computer Science and Technology Tsinghua University Haidian Beijing China

We investigate the mesoscopic transport through a twisted bilayer graphene (TBG) consisting of a clean graphene nanoribbon on the bottom and a disordered graphene disc on the top. We show that, with strong top-layer disorder the transmission through such a device shows a sequence of resonant peaks with respect to the rotation angle θ, where at the resonance angles θc the disc region contains one giant hexagonal moiré supercell. A further investigation shows that the value of θc shows negligible dependence on the disorder strength, the Fermi energy, and the shape distortion, indicating the resonance is a robust geometric feature of the moiré supercell. We explain this geometric resonance based on the bound states formed inside the moiré supercell, with their averaged local density of states dominating at the AA stacking region while minimizing at the AB stacking region. By increasing the interlayer distance, the peak becomes less pronounced which further confirms the role of interlayer coupling. The results presented here suggest a new mechanism to tune the quantum transport signal through the twist angle in disordered moiré systems. Copyright © 2023, The Authors. All rights reserved.

关键词： Resonant tunneling

Brain Cortical Surface Can Predict Fiber Trajectories

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Brain Cortical Surface Can Predict Fiber Trajectories

IEEE International Symposium on Biomedical Imaging

作者： Tianle Han Yifan Lv Mengshen He Yiheng Liu Tianming Liu Bao Ge School of Physics & Information Technology Shaanxi Normal University Xi'an China Department of Computer Science and Bioimaging Research Center Cortical Architecture Imaging and Discovery Lab The University of Georgia GA USA

ISBN: (数字)9798350313338

ISBN: (纸本)9798350313345

Gray matter and white matter are fundamental constituents of the brain, and exploring the relationship between them is for gaining insights into the intricate architecture of the brain. This study utilizes information extracted from the gray matter surface of the brain to predict the trajectories of white matter fibers. Specifically, it predicts the coordinates of fiber trajectories by utilizing both fiber endpoints and reference points on the cortical surface. Both qualitative analysis and extensive quantitative experiments confirm that information derived from the brain's cortical surface can be employed to predict fiber trajectories. Furthermore, this conclusion remains robust across diverse fiber tracking and surface reconstruction techniques. The study introduces a novel perspective, elucidating the fundamental principles of fiber connectivity and the intricate relationship between gray matter and white matter.

关键词： Surface reconstruction Brain Pathology Nerve fibers Magnetic resonance imaging Grey matter Streaming media

Overexpression of Sirt6 ameliorates sleep deprivation induced-cognitive impairment by modulating glutamatergic neuron function

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Neural Regeneration Research 2023年第11期18卷 2449-2458页

作者： Jinpiao Zhu Chang Chen Zhen Li Xiaodong Liu Jingang He Ziyue Zhao Mengying He Binbin Nie Zili Liu Yingying Chen Kuanpin Su Xiang Li Juxiang Chen Hongbing Xiang Fuqiang Xu Kangguang Lin Zongze Zhang Jie Wang Department of Anesthesiology Brain Research CenterDepartment of NeurosurgeryZhongnan HospitalWuhan UniversityWuhanHubei ProvinceChina Department of Anesthesiology and Pain Medicine Tongji Hospital of Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Anesthesia and Intensive Care Peter Hung Pain Research InstituteThe Chinese University of Hong KongHong Kong Special Administration RegionChina Key Laboratory of Magnetic Resonance in Biological Systems State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsNational Center for Magnetic Resonance in WuhanWuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of Sciences-Wuhan National Laboratory for OptoelectronicsWuhanHubei ProvinceChina Key Laboratory of Nuclear Radiation and Nuclear Energy Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijingChina The Brain Cognition and Brain Disease Institute(BCBDI) NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal ProductsShenzhen Key Laboratory of Viral Vectors for BiomedicineShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research InstitutionsShenzhenGuangdong ProvinceChina Mind-Body Interface Research Center(MBI-Lab) China Medical University HospitalTaichungTaiwanChina An-Nan Hospital China Medical UniversityTainanTaiwanChina Department of Neurosurgery Changhai HospitalNaval Medical UniversityShanghaiChina Department of Affective Disorders The Affiliated Brain Hospital of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Institute of Neuroscience and Brain Diseases Xiangyang Central HospitalAffiliated Hospital of Hubei University of Arts and ScienceXiangyangHubei ProvinceChina University of Chinese Academy of Sciences BeijingChina

Sleep benefits the restoration of energy metabolism and thereby suppo rts neuronal plasticity and cognitive ***6 is a NAD+-dependent protein deacetylase that has been recognized as an essential regulator of energy metabolism because it modulates various transcriptional regulators and metabolic *** aim of this study was to investigate the influence of Sirt6 on cerebral function after chronic sleep deprivation(CSD).We assigned C57BL/6J mice to control or two CSD groups and subjected them to AAV2/9-CMV-EGFP or AAV2/9-CMV-Sirt6-EGFP infection in the prelimbic cortex(PrL).We then assessed cerebral functional connectivity(FC) using resting-state functional MRI,neuron/astrocyte metabolism using a metabolic kinetics analysis;dendritic spine densities using sparse-labeling;and miniature excitato ry postsynaptic currents(mEPSCs) and action potential(AP) firing rates using whole-cell patchclamp *** addition,we evaluated cognition via a comprehensive set of behavioral *** with controls,Sirt6 was significantly decreased(P<0.05) in the PrL after CSD,accompanied by cognitive deficits and decreased FC between the PrL and accumbens nucleus,piriform cortex,motor co rtex,somatosensory co rtex,olfactory tubercle,insular cortex,and ***6 ove rexpression reve rsed CSD-induced cognitive impairment and reduced *** analysis of metabolic kinetics using [1-13C] glucose and [2-13C] acetate showed that CSD reduced neuronal Glu4and GABA2synthesis,which could be fully restored via forced Sirt6 ***,Sirt6 ove rexpression reversed CSD-induced decreases in AP firing rates as well as the frequency and amplitude of mEPSCs in PrL pyramidal *** data indicate that Sirt6 can improve cognitive impairment after CSD by regulating the PrL-associated FC network,neuronal glucose metabolism,and glutamatergic ***,Sirt6 activation may have potential as a novel strategy for treating sleep disorder-related diseases.

关键词： chronic sleep deprivation cognitive impairment functional connectivity glutamatergic neurons metabolic kinetics neuronal-astrocytic glucose metabolism prelimbic cortex REM sleep Sirt6 synaptic function

Enhanced quantum frequency estimation by nonlinear scrambling

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arXiv 2025年

作者： Montenegro, Victor Dornetti, Sara Ferraro, Alessandro Paris, Matteo G.A. Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Chengdu611731 China Key Laboratory of Quantum Physics and Photonic Quantum Information Ministry of Education University of Electronic Science and Technology of China Chengdu611731 China Quantum Technology Lab Applied Quantum Mechanics Group Dipartimento di Fisica "Aldo Pontremoli" Università degli Studi di Milano MilanoI-20133 Italy

Frequency estimation, a cornerstone of basic and applied sciences, has been significantly enhanced by quantum sensing strategies. Despite breakthroughs in quantum-enhanced frequency estimation, key challenges remain: static probes limit flexibility, and the interplay between resource efficiency, sensing precision, and potential enhancements from nonlinear probes remains not fully understood. In this work, we show that dynamically encoding an unknown frequency in a nonlinear quantum electromagnetic field can significantly improve frequency estimation. To provide a fair comparison of resources, we define the energy cost as the figure of merit for our sensing strategy. We further show that specific higher-order nonlinear processes lead to nonlinear-enhanced frequency estimation. This enhancement results from quantum scrambling, where local quantum information spreads across a larger portion of the Hilbert space. We quantify this effect using the Wigner-Yanase skew information, which measures the degree of noncommutativity in the Hamiltonian structure. Our work sheds light on the connection between Wigner-Yanase skew information and quantum sensing, providing a direct method to optimize nonlinear quantum probes. Copyright © 2025, The Authors. All rights reserved.

关键词： Hamiltonians

First-principles calculations to investigate Electronic, Optical, Mechanical, and transport characteristics of novel A₂BAuCl₆ (A = K/Rb/Cs;B = Sc/Y)

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Results in physics 2024年 66卷

作者： Israr, Nabeel Alresheedi, Faisal Saeed, Muhammad Rasool Chaudhry, Aijaz Awais Jehangir, Muhammad Murtaza, G. Materials Modeling Lab Department of Physics Islamia College Peshawar Pakistan Department of Physics College of Science Qassim University Buraidah 51452 Saudi Arabia Yangtze Delta Region Institute (Huzhou) University of Electronic Science and Technology of China Huzhou 313001 China School of Physics University of Electronic Science and Technology of China Chengdu 610054 China Department of Physics College of Science University of Bisha P.O. Box 551 Bisha 61922 Saudi Arabia

By utilizing FP-LAPW, the structure, electronic, optical, mechanical and Transport characteristic of A2BAuCl6 (A = K/Rb/Cs, B = Sc/Y) were examined by using DFT. The analysis to the band structure plot of the Halide d... 详细信息

By utilizing FP-LAPW, the structure, electronic, optical, mechanical and Transport characteristic of A₂BAuCl₆ (A = K/Rb/Cs, B = Sc/Y) were examined by using DFT. The analysis to the band structure plot of the Halide double perovskites (HDP's) being studied indicated the existence of indirect band-gaps. The compounds A₂BAuCl₆ (A = K/Rb/Cs, B = Sc/Y) exhibit anisotropic properties, except one compound as seen by their respective shear anisotropy readings of 0.629, 0.532, 1.006, 0.682, 0.803 and 0.977. The materials have inherent ductility, as indicated by their calculated Poisson's ratios in the range of 0.30 to 0.35. The examined (HDP's) materials appear to possess indirect band-gaps, as indicated by the band structure plots. The functional inorganic perovskites A₂BAuCl₆ (A = K/Rb/Cs, B = Sc/Y) haven't similar band-gap values, as determined using the TB-mBJ (modified Becke Johnson) and TB-mBJ + Soc (Spin orbital coupling) assumptions. The visible and ultraviolet domain have prominent peaks, suggesting potential applications of the compounds in solar cells. Moreover, examination of additional optical characteristics such as reflectivity, conductivity, electron energy loss, and absorption coefficients suggest that it possesses the inherent features of a semiconductor. The maximum figure of merit for all the student compounds is above 0.74. The simulated output forms the foundation for A₂BAuCl₆ (A = K/Rb/Cs, B = Sc/Y) and are of practical importance for multijunction solar cells. © 2024 The Author(s)

关键词： Elastic properties Electronic structure Gold based perovskites Optical properties Thermos power conversion