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Chinese physics Letters 2024年第9期41卷 93-106页

作者： Yunqi Ji Xiaohan Wang Xiaohe Li Wenting Tang Xinyang Li Xin Wang Fangfei Li Liang Li Qiang Zhou Synergetic extreme condition User Facility State Key Laboratory of Superhard MaterialsCollege of PhysicsJilin UniversityChangchun 130012China

La_(2)NiO_(4)has a similar structure to La_(2)CuO_(4)and was proposed as a high-temperature superconductor based on magnetic-moment measurements decades ***,with the exception for electrical resistance drop behavior of about 4 orders of magnitude that is claimed to originate from the superconductivity ever observed in Sr-doped La_(N)iO_(4),most electrical data reported to date in La_(N)iO_(4)system exhibit a trivial insulating ground ***,we definitively identify the similar electrical resistance drop behavior of more than 3 orders of magnitude in La_(2)NiO_(4+δ).However,our extensive investigations reveal that this phenomenon is a novel insulatorto-metal transition,distinct from ***,compared to the weak magnetic-field effects,pressure can significantly suppress the transition and transform from the metallic to an insulating ground state,accompanied by an isostructural phase *** work not only elucidates the fundamental properties of the metallic conducting ground state in La_(N)iO_(4)+δ,but also critically challenges the notion of superconductivity in single-layer lanthanum nickelates.

关键词： resistance electrical metallic

Pressure effects on metal/covalent-organic frameworks:structural and optical properties

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Science China Chemistry 2024年第9期67卷 2890-2903页

作者： Yixuan Wang Yunfeng Yang Xinyi Yang Bo Zou Synergetic extreme condition High-Pressure Science Center State Key Laboratory of Superhard MaterialsCollege of PhysicsJilin UniversityChangchun 130012China

Metal-organic frameworks(MOFs)and covalent organic frameworks(COFs)with highly ordered porous structure,tunable bandgap,large specific surface area and structural diversity,provide an appealing platform for the development of stimulus response,sensing,imaging and *** various tuning methods,pressure engineering using the diamond anvil cell is a highly powerful in-situ technique,which can efficiently modulate the structural and optical properties of MOFs/*** is beyond the realization of traditional chemical *** review outlines the research progress in the experimentoriented discovery of new phases or unique properties under high pressure,including phase transition,abnormal compression,photoluminescence(PL)discoloration and ***,the improvement of PL quantum yield in MOFs could be achieved by pressure-treated engineering and hydrogen-bonding cooperativity *** also propose and establish the relationship between structure and optical properties under high ***,the challenge and outlook of the current fields are *** hope that this review will supply guidance for comprehending the development of high-pressure MOF/COF-related research fields,and offer novel strategies for designing more high-performance MOF/COF materials to ultimately expand their applications.

关键词： metal/covalent-organic frameworks pressure engineering phase transition abnormal compressive behaviors piezochromic behaviors emission enhancement

Ultrasonic Properties of the MgB_(2) Superconductor

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Chinese physics Letters 2001年第10期18卷 1369-1370页

作者： LI Shao-Chun WANG Ru-Ju LI Feng-Ying LIU Zhen-Xing ZHU Jia-Lin YU Ri-cheng JIN Chang-Qing laboratory for extreme condition physics Institute of Physicsand Center for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080 Beijing Center for High Pressure Research Chinese Academy of SciencesBeijing 100080

The sound velocities of longitudinal and shear waves are measured on a polycrystalline MgB_(2) superconductor with Tc of 39 K. The specimen used in the experiments is pressed and heated using the MgB_(2) powder. The elastic moduli, Debye temperature and specific heat at room temperature are obtained based on sound velocity data. The results indicate that the velocities are much higher than those in the usual materials, while elastic constants remain reasonably soft, which may be due to the high transition temperature of the MgB2 superconductor.

关键词： heated Superconductor superconductor

The detection, extraction and parameter estimation of extreme-mass-ratio inspirals with deep learning

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Science China(physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 86-96页

作者： Qianyun Yun Wen-Biao Han Yi-Yang Guo He Wang Minghui Du Hangzhou Institute for Advanced Study University of Chinese Academy of Sciences Shanghai Astronomical Observatory Chinese Academy of Sciences School of physics and Astronomy Shanghai Jiao Tong University School of Astronomy and Space Science University of Chinese Academy of Sciences Taiji laboratory for Gravitational Wave Universe (Beijing/Hangzhou) University of Chinese Academy of Sciences Lanzhou Center for Theoretical physics Key Laboratory of Theoretical Physics of Gansu Province Key Laboratory of Quantum Theory and Applications of MoE Lanzhou University Institute of Theoretical physics & Research Center of Gravitation Lanzhou University International Centre for Theoretical physics Asia-Pacific (ICTP-AP) University of Chinese Academy of Sciences (UCAS) Center for Gravitational Wave Experiment National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences

One of the primary goals of space-borne gravitational wave detectors is to detect and analyze extreme-mass-ratio inspirals(EMRIs). This task is particularly challenging because EMRI signals are complex, lengthy, and faint. In this work, we introduce a2-layer convolutional neural network(CNN) approach to detect EMRI signals for space-borne detectors, achieving a true positive rate(TPR) of 96.9% at a 1% false positive rate(FPR) for signal-to-noise ratio(SNR) from 50 to 100. Especially, the key intrinsic parameters of EMRIs such as the mass, spin of the supermassive black hole(SMBH) and the initial eccentricity of the orbit can also be inferred directly by employing a neural network. The mass and spin of the SMBH can be determined at 99% and 92% respectively. This will greatly reduce the parameter spaces and computing cost for the following Bayesian parameter *** model also has a low dependency on the accuracy of the waveform model. This study underscores the potential of deep learning methods in EMRI data analysis, enabling the rapid detection of EMRI signals and efficient parameter estimation.

关键词： gravitational wave EMRIs deep-learing

Low Temperature Specific Heat of Superconducting MgB_(2)

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Chinese physics Letters 2001年第6期18卷 820-822页

作者： LUO Jian-Lin ZHANG Jie CHEN Zhao-Jia BAI Hai-Yang WANG Yu-Peng MENG Ji-Bao JIN Duo REN Zhi-An CHE Guang-Can ZHAO Zhong-Xian laboratory of extreme condition physics Institute of Physics and Center for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080 National laboratory for Superconductivity Institute of Physics and Center for Condensed Matter PhysicsChinese Academy of SciencesBeijing 100080 Department of physics Chongqing UniversityChongqing 400044

The specific heat of the recently discovered superconductor MgB_(2) has been measured at temperatures ranging from 4.5 to 80 *** anomalyΔC at Tc is clearly *** total specific heat in normal state can be well fitted by electronic and phonon *** Debye temperatureθD is obtained to be 737 K,much larger than other intermetallic *** state electronic specific heat coefficientγis found to be 2.48±0.5 mJ/mol.K^(2) andΔC/γTc is between 1.41 and 2.15.

关键词： intermetallic superconductor electronic

High-pressure and high-tem-perature synthesis of MgB_2 and its superconductivity

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Chinese Science Bulletin 2001年第22期46卷 1932-1934页

作者： ZHU Jialin, LI Shaochun, YU Richeng, LI Fengying LIU Zhengxing & JIN Changqinglaboratory for extreme condition physics, Institute of physics, Center for Condensed Matter Physcis and Beijing High Pressure Research Center, Chinese Academy of Sciences, Beijing 100080, China laboratory for extreme condition physics Institute of Physics Center for Condensed Matter Physcis and Beijing High Pressure Research Center Chinese Academy of Sciences Beijing China

The single-phase sample of MgB2 was prepared successfully at the temperature of 900℃ and under the pressure of 3 GPa. The structure of the sample was investigated using powder X-ray diffraction and Rietveld analysis. The results show that the structure of the sample belongs to the hexagonal structure with space group of P6/mmm, a=3.0861(5) A, c=3.5222(8) A. The magnetic and resistance measurements indicate that the superconducting transition temperature Tc is 39 K.

关键词： superconductivity magnetization resistance.

Influence of Weave Structures on the Tribological Properties of Hybrid Kevlar/PTFE Fabric Composites

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Chinese Journal of Mechanical Engineering 2012年第5期25卷 1044-1051页

作者： GU Dapeng YANG Yulin QI Xiaowen DENG Wei SHI Lei Key laboratory of Fundamental Science of Mechanical Structure and Material Science under extreme condition for National Defence Yanshan UniversityQinhuangdao 066004China

The existing research of the woven fabric self-lubricating liner mainly focus on the tribological performance improvements and the service life raised by changing different fiber type combinations, adding additive modification, and performing fiber surface modification. As fabric composites, the weave structures play an important role in the mechanical and tribological performances of the liners. However, hardly any literature is available on the friction and wear behavior of such composites with different weave structures. In this paper, three weave structures （plain, twill 1/3 and satin 8/5） of hybrid Kevlar/PTFE fabric composites are selected and pin-on-flat linear reciprocating wear studies are done on a CETR tester under different pressures and different frequencies. The relationship between the tensile strength and the wear performance are studied. The morphologies of the worn surfaces under the typical test conditions are analyzed by means of scanning electron microscopy （SEM）. The analysis results show that at 10 MPa, satin 8/5 performs the best in friction-reduction and antiwear performance, and plain is the worst. At 30 MPa, however, the antiwear performance is reversed and satin 8/5 does not even complete the 2 h wear test at 16 Hz. There is no clear evidence proving that the tensile strength has an influence on the wear performance. So the different tribological performance of the three weave structures of fabric composites may be attributed to the different PTFE proportions in the fabric surface and the different wear mechanisms. The fabric composites are divided into three regions： the lubrication region, the reinforced region and the bonding region. The major mechanisms are fatigue wear and the shear effects of the friction force in the lubrication region. In the reinforced region fiber-matrix de-bonding and fiber breakage are involved. The proposed research proposes a regional wear model and further indicates the wear process and the wear mechanism o

关键词： hybrid Kevlar/PTFE fabric composite friction wear weave structure scanning electron microscopy

High-pressure new phases of V–N compounds

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Chinese physics B 2023年第5期32卷 560-565页

作者：时旭含李志慧刘媛媛王元元刘冉胡阔姚震 Synergetic extreme condition High-Pressure Science Center State Key Laboratory of Superhard MaterialsCollege of PhysicsJilin UniversityChangchun 130012China Aviation University of Air Force Changchun 130022China

The high-pressure diagram of V–N compounds is enriched by proposed seven new stable high-pressure *** P-1-VN_4with the armchair N-rich structure may be quenched to ambient *** formed N–N covalent bond plays an important role for the structural stability of *** charge transfer results in a V–N ionic bond interaction,which further improves the stability of N-chain *** P-1-VN_4,P4mnc-VN_8,and Immm-VN_(10)with the outstanding detonation properties have potential application in explosive field.

关键词： high-pressure N-rich V–N compounds phase diagram stability DFT calculation

Quantum public-key crypto via EPR pairs

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Science China(physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 58-63页

作者： Xiang-Qun Fu Hong-Wei Li Jian-Hong Shi Tan Li Wan-Su Bao Henan Key laboratory of Quantum Information and Cryptography Information Engineering University Synergetic Innovation Center of Quantum Information and Quantum physics University of Science and Technology of China

With the development of quantum computing technology, quantum public-key cryptography is gradually becoming an alternative to the existing classical public-key cryptography. This paper designs a quantum trapdoor one-way function via EPR pairs and quantum measurements. Based on this, a new quantum public-key cryptosystem is presented, which offers forward security,and can resist the chosen-plaintext attack and chosen-ciphertext attack. Compared with the existing quantum public-key cryptos,eavesdropping can be automatically detected in this new quantum public-key cryptosystem under a necessary condition, which is also detailed in the paper.

关键词： quantum public-key crypto trapdoor one-way function EPR pairs

Pressure generation under deformation in a large-volume press

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Chinese physics B 2024年第9期33卷 622-626页

作者： Saisai Wang Xinyu Zhao Kuo Hu Bingtao Feng Xuyuan Hou Yiming Zhang Shucheng Liu Yuchen Shang Zhaodong Liu Mingguang Yao Bingbing Liu State Key laboratory of Superhard Materials Synergetic Extreme Condition User FacilityCollege of PhysicsJilin UniversityChangchun 130012China College of Earth Sciences Jilin UniversityChangchun 130012China

Deformation can change the transition pathway of materials under high pressure,thus significantly affects physical and chemical properties of ***,accurate pressure calibration under deformation is challenging and thereby causes relatively large pressure uncertainties in deformation experiments,resulting in the synthesis of complex multiphase ***,pressure generations of three types of deformation assemblies were well calibrated in a Walker-type largevolume press(LVP)by electrical resistance measurements combined with finite element simulations(FESs).Hard Al_(2)O_(3) or diamond pistons in shear and uniaxial deformation assemblies significantly increase the efficiency of pressure generation compared with the conventional quasi-hydrostatic *** uniaxial deformation assembly using flat diamond pistons possesses the highest efficiency in these deformation *** finding is further confirmed by stress distribution analysis based on *** this deformation assembly,we found shear can effectively promote the transformation of C60 into diamond under high pressure and realized the synthesis of phase-pure diamond at relatively moderate pressure and temperature *** present developed techniques will help improve pressure efficiencies in LVP and explore the new physical and chemical properties of materials under deformation in both science and technology.

关键词： shear/uniaxial deformation pressure calibration finite element simulations large-volume press high pressure