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Science China(Physics,Mechanics & Astronomy) 2023年第6期66卷 87-93页

作者： Xinpeng Wang Ying-li Zhang Rampei Kimura Masahide Yamaguchi School of Physics Science and Engineering Tongji UniversityShanghai200092China Institute for Advanced Study of Tongji University Shanghai200092China Kavli Institute for the Physics and Mathematics of the Universe(wpi) Chiba277-8583Japan Center for Gravitation and Cosmology Yangzhou UniversityYangzhou225009China Waseda Institute for Advanced Study Waseda UniversityTokyo169-8050Japan Department of Physics Tokyo Institute of TechnologyTokyo152-8551Japan

As a candidate bound for the Binary Black Hole(BBH) merger events detected by LIGO/Virgo, Primordial Black Holes(PBHs)provide a useful tool to investigate the primordial curvature perturbations on small scales. Using the GWTC-1 to GWTC-3 catalogs, under the scenario that PBHs originate from large primordial curvature perturbations on small scales during infiationary epoch, we for the first time reconstruct the power spectrum of primordial curvature perturbations on small scales. It is found that the value of the amplitude of the primordial power spectrum is enhanced to O(10-2)on scales O(1) pc. This may imply the validity of PBH as a possible BBH merger candidate.

关键词： primordial black hole primordial curvature perturbation gravitational wave inflation

基于高维多属性决策过程的复杂地表初至波识别与走时检测方法

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石油物探 2022年第4期61卷 599-608,704页

作者：李康丽冯波王华忠波现象与智能反演成像研究组(wpi) 同济大学海洋与地球科学学院上海200092

波动理论初至波走时层析速度反演及建模成为当今陆上地震波成像中关键步骤之一、“两宽一高”地震数据采集技术的逐渐普及使得人工进行海量数据的初至波识别及走时检测变得不再可行、复杂地表区的油气勘探越来越成为常规、各种机器学习... 详细信息

波动理论初至波走时层析速度反演及建模成为当今陆上地震波成像中关键步骤之一、“两宽一高”地震数据采集技术的逐渐普及使得人工进行海量数据的初至波识别及走时检测变得不再可行、复杂地表区的油气勘探越来越成为常规、各种机器学习算法的出现,所有这些因素都要求人们必须进一步深入探索高精度的初至波识别及走时检测方法。将问题定位为弱初至波掩埋在(较)强噪声中,提出了一套复杂地表区初至波识别及走时检测的自动化智能化处理技术流程,主要步骤包括炮集中与初至波相关的预处理、高维特征空间的构建、多属性加权K均值聚类划分初至波分布区域、多属性约束的马尔可夫决策过程(Markov decision process,MDP)进行初至走时检测等。在MDP理论框架下,选择合理的基准面消除初至波高频道间时差,将三维(或二维)炮集中的初至波场视为一个有机的整体,提取高维特征属性,引入多属性加权K均值聚类划分出初至波分布区域,缩小拾取范围,利用多属性约束构建马尔可夫最优演化算法,充分考虑初至信息之间的横向连续性,进行初至波走时检测。实际数据测试结果表明,该方法能够自动地以较高的精度和稳健性进行初至走时的拾取,在中等复杂度情形下有较好的实用效果。

关键词：初至波识别走时检测高维特征空间 K均值聚类马尔可夫决策多属性约束

A dynamic database of solid-state electrolyte(DDSE)picturing all-solid-state batteries

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Nano Materials Science 2024年第2期6卷 256-262页

作者： Fangling Yang Egon Campos dos Santos Xue Jia Ryuhei Sato Kazuaki Kisu Yusuke Hashimoto Shin-ichi Orimo Hao Li Advanced Institute for Materials Research(wpi-AIMR) Tohoku UniversitySendai980-8577Japan Key Laboratory of Radiation Physics and Technology Ministry of EducationCollege of PhysicsSichuan UniversityChengdu610065People's Republic of China Institute for Materials Research(IMR) Tohoku UniversitySendai980-8577Japan Tohoku Forum for Creativity Tohoku UniversitySendai980-8577Japan

All-solid-state batteries(ASSBs)are a class of safer and higher-energy-density materials compared to conventional devices,from which solid-state electrolytes(SSEs)are their essential *** date,investigations to search for high ion-conducting solid-state electrolytes have attracted broad ***,obtaining SSEs with high ionic conductivity is challenging due to the complex structural information and the less-explored structure-performance *** provide a solution to these challenges,developing a database containing typical SSEs from available experimental reports would be a new avenue to understand the structureperformance relationships and find out new design guidelines for reasonable ***,a dynamic experimental database containing>600 materials was developed in a wide range of temperatures(132.40–1261.60 K),including mono-and divalent cations(e.g.,Li^(+),Na^(+),K^(+),Ag^(+),Ca^(2+),Mg^(2+),and Zn^(2+))and various types of anions(e.g.,halide,hydride,sulfide,and oxide).Data-mining was conducted to explore the relationships among different variates(e.g.,transport ion,composition,activation energy,and conductivity).Overall,we expect that this database can provide essential guidelines for the design and development of high-performance SSEs in ASSB *** database is dynamically updated,which can be accessed via our open-source online system.

关键词： Solid-state electrolyte(SSE) All-solid-state battery(ASSB) Ionic conductivity Dynamic database Machine learning

Ultrasonic Image Registration for Multi-Frequency Analysis

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Open Journal of Acoustics 2013年第3期3卷 1-8页

作者： Naomi Yagi Tomomoto Ishikawa Yutaka Hata Graduate School of Engineering University of Hyogo Himeji Japan Ishikawa Hospital Himeji Japan wpi Immunology Frontier Research Center Osaka University Osaka Japan

This paper describes ultrasonic image registration for multi-frequency analysis. The goal of our research is the portable and real time brain diagnosis under the thick-skull. The choice of ultrasonic frequency is a trade-off between spatial image resolution and imaging depth. This study shows the usability of data synthesis by employing two different frequency ultrasounds. In the first part of this study, using Fast Fourier Transform, we conclude that the synthesized image was produced from two ultrasonic images of individual objects. The purpose of the second approach of the data synthesis is to investigate three methods of ultrasonic imaging. This approach is particular interest for the design of further study intending to visualize any defects by ultrasonic methods. As the results, the synthesized image with Wavelet transform has higher efficiency than the other synthesized ones for the bone and the sulcus. In summary, this study indicates that the ultrasonic synthesized image is useful to visualize the imitated brain area. This observation is encouraging for further studies of evaluating brain for patients.

关键词： Ultrasound Human Brain Data Synthesis Fourier Transform Wavelet Transform

Investigation of energy-efficient solid desiccant system for wheat drying

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International Journal of Agricultural and Biological Engineering 2019年第1期12卷 221-228页

作者： Shazia Hanif Muhammad Sultan Takahiko Miyazaki Shigeru Koyama Interdisciplinary Graduate School of Engineering Sciences Kyushu UniversityFukuoka 816-8580Japan Department of Agricultural Engineering Bahauddin Zakariya UniversityMultan 60800Pakistan Faculty of Engineering Sciences Kyushu UniversityFukuoka 816-8580Japan International Institute for Carbon-Neutral Energy Research(wpi-I2CNER) Kyushu UniversityFukuoka 819-0395Japan

The study investigates the applicability of solid desiccant system for drying of freshly harvested wheat grains in order to reduce the moisture content to an optimum *** and low-temperature drying systems are required by today’s drying industries in order to provide economical and safe ***,comparison of desiccant drying has been made with the conventional method in terms of drying kinetics,allowable time for safe storage,the total time for drying cycle,and overall energy *** has been found that the air conditions of proposed desiccant drying system provides a high drying rate and longer allowable storage time for safe *** the desiccants possess water adsorbing ability by means of vapor pressure deficit,therefore,the desiccant system successfully provides low-temperature drying which ensures the quality of wheat *** energy consumption is estimated for both conventional hot air drying and desiccant drying *** has been found that the desiccant system requires less energy as drying is accomplished at minimum level of air flow and within allowable storage *** addition,the overall performance index of the desiccant system is higher at all *** study is useful for developing a low-cost and sustainable drying technology for various agricultural products.

关键词： desiccant solid desiccant system drying grain wheat performance evaluation

Spatially-controlled porous nanoflake arrays derived from MOFs:An efficiently long-life oxygen electrode

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Nano Research 2019年第10期12卷 2528-2534页

作者： Hao Gong Tao Wang Hairong Xue Xueyi Lu Wei Xia Li Song Songtao Zhang Jianping HeRenzhi Ma College of Materials Science and Technology^Jiangsu Key Laboratory of Materials and Technology for Energy Conversion Nanjing University(rf Aeronautics and AstronauticsNanjing 210016China International Center for Materials Nanoarchitectonics(wpi-MANA) National Institute for Materials Science(NIMS)1-1 NatnikiTsukubaIbaraki 305-0044Japan School of Chemistry and Chemical Engineering South China University of TechnologyWushan Road 381Guangzhou 510641China Testing Center Yangzhou UniversityYangzhou 225009China

The urge nt expectati on of the n ext-ge neratio n en ergy storage devices for electric vehicles has drive n researchers'atte ntion to the lithium-oxyge n(Li-O2)batteries due to the satisfied specific energy ***,spatially-controlled CO3O4 nanoflake arrays with three-dimensional networked morphology are adopted as flexible and self-sta nding oxyge n cathodes in L1-O2 *** spin el-phase CO3O4 nano flakes were con verted from two dimensi on metal-orga nic frameworks with abundant available cha nnels and large specific surface *** open-structure nano flake arrays possess sufficie nt Li2O2/cathode contact interface,great bifunctional catalytic performa nee and adequate Li2O2 accommodation,leading to the enhanced electrochemical performance of the L1-O2 *** expected,the binder-free porous CO3O4/CT cathode delivers a high capacity of 6,509 mAh·g^-1(200 mA·g^-1)and enhanced stability over 100 cycles(limited by 1,000 mAh·g^-1).In additi on,pouch-type Li-O2 batteries were successfully desig ned and cycled with CO3O4/CT cathode as oxyge n electrodes,dem on strating its potential application for flexible electronics and wearable energy storage devices.

关键词： two-dimension metal-organic frameworks mesoporous CO3O4 flexible oxygen electrode lithium-oxygen batteries

Texture adjustment approach of magnesium alloys via variable strain path calculated by an integrated finite element-viscoplastic self-consistent model

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Journal of Materials Science & Technology 2024年第17期184卷 15-31页

作者： Wenjie Wu Wenzhen Chen Xiaoyu Wang Wenke Wang Wencong Zhang Xinhua Liu Hyoung Seop Kim School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory for Advanced Materials Processing(MOE) Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China Graduate Institute of Ferrous&Energy Materials Technology(GIFT) Pohang University of Science and Technology(POSTECH)Pohang 37673South Korea Advanced Institute for Materials Research(wpi-AIMR) Tohoku UniversitySendai 9808577Japan

An integrated calculated approach based on weakly coupled finite element(FEM)-viscoplastic selfconsistent(VPSC)model was established to simulate the texture evolution during the variable strain path extrusion process of magnesium *** spiral die extrusion(SDE)process with additional circumferential shear deformation was applied to investigate the effect of path control on texture adjustment and verify the accuracy of the *** results indicated that the additional spiral shear resulting from the overall inclined flow path effectively reduced the intensity of the{0002}//ED fiber texture by suppressing basal slip activation in the core area,while the local shear deformation along the spiral equal channel strain path led to the formation of an inclined{0002}//ND plane texture on the *** the modified Hall-Petch relationship,the correlation between texture and yield strength was ***,the weakening of the texture effectively suppressed{10-12}tensile twinning,which compensated for the deficiency of compressive yield strength without significantly sacrificing tensile yield strength,and thus improved the tension-compression ***,the strongly inclined{0002}//ND plane texture inhibited the widespread activation of basal slip during tensile yielding,thereby enhancing the yield strength.

关键词： Integrated calculated approach Strain path control Texture adjustment Spiral die extrusion Viscoplastic self-consistent

Mass Distribution of Black Holes with Effects of Convective Carbon Shell Burning on Pair-instability Pulsation and Fe Core Collapse

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Research in Astronomy and Astrophysics 2023年第1期23卷 153-160页

作者： Wenyu Xin Ken’ichi Nomoto Gang Zhao Xianfei Zhang CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Kavli Institute for the Physics and Mathematics of the Universe(wpi) The University of Tokyo Institutes for Advanced StudyThe University of TokyoKashiwaChiba 277-8583Japan Department of Astronomy Beijing Normal UniversityBeijing 100875China

Motivated by the determination of black hole masses with gravitational-wave observations,we calculate the evolution of massive stars through presupernova stages and obtain the mass distribution of black *** the first part,we calculate the evolution of He stars with masses of 30-120 M_(⊙).We study in detail how convective carbon shell burning controls pair-instability pulsations before and during oxygen burning and determine their final *** the second part,we calculate the evolution of H-rich stars with initial masses of 13-80 M_(⊙) until Fe core collapse and obtain the possible black hole mass range by applying the criterion of the compactness *** these models,we predict the mass distribution of black holes for stars that undergo Fe core collapse and pair-instability *** predicted masses for black holes range from 4.2 to 46 M_(⊙),which are consistent with the gravitational-wave observations.

关键词： gravitational waves-stars black holes-stars evolution-stars massive-(stars:)supernovae general

Féeton(B-L gauge boson)dark matter for the 511-keV gamma-ray excess and the prediction of low-energy neutrino flux

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Chinese Physics C 2024年第8期48卷 76-82页

作者： Jie Sheng Yu Cheng Weikang Lin Tsutomu T.Yanagida Tsung-Dao Lee Institute&School of Physics and Astronomy Shanghai Jiao Tong UniversityChina Key Laboratory for Particle Astrophysics and Cosmology(MOE)&Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai Jiao Tong UniversityShanghai 200240China South-Western Institute For Astronomy Research Yunnan UniversityKunming 650500China Kavli IPMU(wpi) UTIASUniversity of TokyoKashiwa277-8583Japan

The féeton is the gauge boson of the U(1)_(B−L) gauge *** the gauge coupling constant is extremely small,the féeton becomes a candidate for dark *** show that its decay to a pair of an electron and a positron explains the observed Galactic 511-keV gamma-ray excess in a consistent *** féeton dark matter decays mainly into pairs neutrino and *** low-energy experiments with improved directional capability will enable capturing these neutrino *** seesaw-motivated parameter space predicts a relatively short féeton lifetime that is comparable to the current cosmological constraint.

关键词： feeton 511-keV gamma-ray excess low-energy neutrino

Direct Observation of High-Temperature Superconductivity in One-Unit-Cell FeSe Films

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Chinese Physics Letters 2014年第1期31卷 156-160页

作者：张文号孙袆张金松李坊森郭明华赵弇斐张慧敏彭俊平邢颖王慧超 FUJITA Takeshi HIRATA Akihiko 李志丁浩汤辰佳王萌王庆艳何珂季帅华陈曦王俊峰夏正才李亮王亚愚王健王立莉陈明伟薛其坤马旭村 State Key Lab of Low-Dimensional Quantum Physics Department of Physics Tsinghua University Beijing 100084 International Center for Quantum Materials School of Physics Peking University Beijing 100871 Collaborative Innovation Center of Quantum Matter Beijing Institute of Physics Chinese Academy of Sciences Beijing 100190 wpi Advanced Institute for Materials Research Tohoku University Sendai 9808577 Japan Wuhan National High Magnetic Field Center Huazhong University of Science and Technology Vguhan 430071

We prepared one-unit-ceil （1-UC） thick FeSe films on insulating SrTiOa substrates with non-superconducting FeTe protection layers by molecular beam epitaxy for ex situ studies. By direct transport and magnetic measurements, we provide definitive evidence for high temperature superconductivity in the 1-UC FeSe films with an onset Tc above 40 K and an extremely large critical current density fie Jc-1.7× 106 A/cm2 at 2K, which are much higher than Tc-8K and Jc-104 A/cm^2 for bulk FeSe, respectively. Our work may pave the way to enhancing and tailoring superconductivity by interface engineering.

关键词： Selenium compounds