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Nuclear Science and Techniques 2023年第1期34卷 33-42页

作者： jun‑Hua Luo jun‑cheng liang Li Jiang Fei Tuo liang Zhou Long He Institute of New Energy Hexi UniversityZhangye 734000China School of Physics and Electromechanical Engineering Hexi UniversityZhangye 734000China National Institute of Metrology Beijing 100029China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China China CDC National Institute for Radiological ProtectionBeijing 100088China

A lead-shielded HPGe detector and offlineγ-ray spectra of the residual product were used to measure the cross section(CS)and ratios of isomeric CS(σm/σg)in^(134)Xe(n,2n)^(133m),gXe reactions at different energies(13.5 MeV,13.8 MeV,14.1 MeV,14.4 MeV,14.8 MeV)relative to the^(93)Nb(n,2n)^(92)mNb reaction *** target was high-purity natural Xe gas under high *** T(d,n)4He reaction produces *** code(version 1.95)for nuclear reactions was used for calculations,with default parameters and nuclear level density *** uncertainties in the measured CS data were thoroughly analyzed using the covariance analysis *** results were compared with theoretical values,evaluation data,and previous experimental *** data of the 134Xe(n,2n)133mXe and 134Xe(n,2n)133gXe reactions and the corresponding isomeric CS ratios at 13.5 MeV,13.8 MeV,and 14.1 MeV neutron energies are reported for the first *** research advances our knowledge of pre-equilibrium emission in the(n,2n)reaction channel by resolving inconsistencies in the Xe data.

关键词： ^(134)Xe(n,2n)reactions 14-MeV neutrons Cross sections(CSs) Isomeric ratios(IRs) Covariance analysis

Bose–Einstein condensates with tunable spin–orbit coupling in the two-dimensional harmonic potential: The ground-state phases, stability phase diagram and collapse dynamics

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Frontiers of physics 2022年第6期17卷 219-233页

作者： Chen Jiao jun-cheng liang Zi-Fa Yu Yan Chen Ai-Xia Zhang Ju-Kui Xue College of Physics and Electronics Engineering Northwest Normal UniversityLanzhou 730070China School of Physics and Electromechanical Engineering Hexi UniversityZhangye 734000China

We study the ground-state phases,the stability phase diagram and collapse dynamics of Bose–Einstein condensates(BECs)with tunable spin–orbit(SO)coupling in the two-dimensional harmonic potential by variational analysis and numerical *** we propose the theory that the collapse stability and collapse dynamics of BECs in the external trapping potential can be manipulated by the periodic driving of Raman coupling(RC),which can be realized *** the high-frequency approximation,an effective time-independent Floquet Hamiltonian with two-body interaction in the harmonic potential is obtained,which results in a tunable SO coupling and a new effective two-body interaction that can be manipulated by the periodic driving *** the variational method,the phase transition boundary and collapse boundary of the system are obtained analytically,where the phase transition between the spin-nonpolarized phase with zero momentum(zero momentum phase)and spin-polarized phase with non-zero momentum(plane wave phase)can be manipulated by the external driving and sensitive to the strong external trapping ***,it is revealed that the collapsed BECs can be stabilized by periodic driving of RC,and the mechanism of collapse stability manipulated by periodic driving of RC is clearly *** addition,we find that the collapse velocity and collapse time of the system can be manipulated by periodic driving strength,which also depends on the RC,SO coupling strength and external trapping ***,the variational approximation is confirmed by numerical simulation of Gross–Pitaevskii *** results show that the periodic driving of RC provides a platform for manipulating the ground-state phases,collapse stability and collapse dynamics of the SO coupled BECs in an external harmonic potential,which can be realized easily in current experiments.

关键词： spin-orbit coupled Bose-Einstein condensates stability collapse dynamics

A Fluorine-Functionalized 3D Covalent Organic Framework with Entangled 2D Layers

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Chinese Journal of Polymer Science 2024年第8期42卷 1210-1216页

作者： Li-Bang Xiao Zi-Han Wu jun-Jie Xin Yuan-Peng cheng Bo Gui jun-liang Sun cheng Wang College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China College of Chemistry and Molecular Engineering Beijing National Laboratory for Molecular SciencesPeking UniversityBeijing 100871China

Constructing three dimensional(3D)covalent organic frameworks(COFs)through the entanglement of two dimensional(2D)nets is a promising but underdeveloped ***,we report the design and synthesis of a fluorine functionalized 3DCOF(3D-An-COF-F)formed by entangled 2D sql *** structure of 3D-An-COF-F was determined by the combination of continuous rotation electron diffraction technique and modelling based on the chemical information from real ***,compared to the isostructural 3D-An-COF without F atom s,3DAn-COF-F showed an improved CO_(2)sorption ability and higher CO_(2)/N_(2)*** study not only demonstrated the generality of constructing 3D COFs with entangled 2D nets by introducing bulky groups vertically in planar building blocks,but also will expand the diversity of 3D COFs for various applications.

关键词： 3D covalent organic frameworks Fluorine Entangled 2D layers Electron diffraction CO_(2)adsorption

Enhanced thermoelectric performance enabled by compositing ZrO_(2)in n-type SiGe alloy with low thermal conductivity

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Rare Metals 2024年第3期43卷 1167-1176页

作者： Meng-Fei Wang Hua-jun Lai Ji-Sheng liang jun-liang Chen Wang-Yang Ding Qi Zhou Ying Peng cheng-Yan Liu Lei Miao Guangxi Key Laboratory for Relativity Astrophysics State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite StructuresSchool of Physical Science and TechnologyGuangxi UniversityNanning530004China Guangxi Academy of Sciences Nanning530007China Key Laboratory of Information Material Engineering Research Center of Electronic Information Materials and DevicesGuilin University of Electronic TechnologyMinistry of EducationGuilin541004China Guangxi Key Laboratory of Precision Navigation Technology and Application School of Information and CommunicationGuilin University of Electronic TechnologyGuilin541004China

SiGe-based thermoelectric(TE)materials have gained increasing interests due to their low maintenance costs,environmental friendliness and long ***,the intrinsically high thermal conductivity of Si-based materials also results in poor TE *** this investigation,a zirconia(ZrO_(2))composite strategy was applied to an n-type SiGe alloy,tremendously elevating its TE *** mechanical alloying and spark plasma sintering(SPS)processes,the ZrO_(2)induced the formation of nanopores in the SiGe matrix via phosphorus ***,such increase in porosity enhanced the phonon scattering and dramatically suppressed lattice thermal conductivity,from 2.83 to 1.59 W·m^(-1)·K^(-1)at 873 ***,reduced phosphorus doping led to an increase in Seebeck coefficients and a relatively minor decrease in electrical conductivity,The power factor didn't deteriorate significantly,either,as its maximum of~3.43 mW·m^(-1-)K^(-2)was achieved at 873 K with(Si_(0.8)Ge_(0.2))_(0.097)P_(0.03)(ZrO_(2))_(0.003).In short,a peak figure of merit(ZT)of~1.27 at 873 K and an average ZT~0.7 from 323 to 873 K were *** study demonstrates that the electrical and thermal transportation of SiGe material can be synergistically tuned by compositing ZrO_(2),illustrating a novel strategy to optimize the TE properties of bulk materials.

关键词： Thermoelectric SiGe alloy ZrO2 composting P element adsorption nanopores

Effect of multiple coulomb scattering on the beam tests of silicon pixel detectors

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Nuclear Science and Techniques 2024年第4期35卷 200-207页

作者： Lan-Kun Li Ming-Yi Dong Ze Gao liang-cheng-Long Jin Shu-jun Zhao School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Particle Detection and Electronics(Institute of High Energy Physics CAS)Beijing 100049China University of Chinese Academy of Science Beijing 100049China University of South China Hengyang 421001China

In the research and development of new silicon pixel detectors,a collimated monoenergetic charged-particle test beam equipped with a high-resolution pixel-beam telescope is crucial for prototype verification and performance *** the beam energy is low,the effect of multiple Coulomb scattering on the measured resolution of the Device Under Test(DUT)must be considered to accurately evaluate the performance of the pixel chips and *** study aimed to investigate the effect of multiple Coulomb scattering on the measured resolution,particularly at low beam *** were conducted using Allpix^(2) to study the effects of multiple Coulomb scattering under different beam energies,material budgets,and telescope *** simulations also provided the minimum energy at which the effect of multiple Coulomb scattering could be *** with the results of a five-layer detector system tested with an electron beam at DESY,the simulation results were consistent with the beam test results,confirming the reliability of the simulations.

关键词： Silicon Pixel Detectors Beam Telescope Multiple Coulomb Scattering Spatial Resolution

Thermoelectric transport properties of p-type Bi2Se3-Sb2Se3-In2Se3 high entropy compounds

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Rare Metals 2024年第7期43卷 3415-3421页

作者： Feng Jiang cheng-liang Xia Yong-Bin Zhu jun Li Yue Chen Wei-Shu Liu Department of Materials Science and Engineering Southern University of Science and Technology Department of Mechanical Engineering The University of Hong Kong Guangdong Provincial Key Laboratory of Functional Oxide Materials and Devices Southern University of Science and Technology

The introduction of entropy concept into thermoelectric materials recently has attracted broad ***,we showed the phase diagram of the ternary systems of *** the high entropy compounds （HECs）,we have identified an in... 详细信息

关键词： Selenium compounds

Imaging and pathological findings of AIDS complicated by pulmonary Rhodococcus equi infection

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Chinese Medical Journal 2011年第7期124卷 968-972页

作者： LI Hong-jun cheng Jing-liang Department of Diagnostic Radiology the Frist Affiliated Hospitalof Zhengzhou University Zhengzhou Henan 450052 China

Background Rhodococcus equi （R. equl） infection commonly occurs in grazing areas, especially in patients with AIDS or with T-lymphocyte immuno-deficiencies. Literature reviews revealed that cases radiologically and pathologically diagnosed of AIDS complicated by R. equi infection are rare. This study aimed to investigate the imaging features and Datholoqical basis of AIDS complicated by pulmonary R. equi infection.

关键词： AIDS Rhodococcus equi pulmonary infection radiological demonstrations pathology

The higher-order topological pumping explored in the 2D acoustic crystal

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 127-133页

作者： Yanqiu Wang Bin liang Jianchun cheng Key Laboratory of Modern Acoustics Ministry of EducationInstitute of AcousticsDepartment of PhysicsNanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

The topological pumping has been instrumental in advancing our understanding of topological phase transitions in various physical systems,which can be extended to uncover intriguing higher-order topological phases in the lower-dimensional ***,we propose a theoretical exploration of topological dipole pumping on an acoustic square superlattice by cyclically modulating intracell couplings,which shares the topological nature of an extended three-dimensional system with chiral hinge *** the multipole chiral numbers,we characterize the higher-order topological phases that arise during the *** evolution of topological phase transitions is verified by numerical simulations and shows corner states are transferred across the *** findings can inspire the construction of chiral hinge states in artificial crystals,opening up new possibilities for the design of devices allowing the unidirectional propagation of sound.

关键词： topological phases of matter Thouless pumping acoustic metamaterial

Transition edge sensor-based detector:from X-ray to γ-ray

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Nuclear Science and Techniques 2022年第7期33卷 61-72页

作者： Shuo Zhang Jing-Kai Xia Tao Sun Wen-Tao Wu Bing-jun Wu Yong-liang Wang Robin Cantor Ke Han Xiao-Peng Zhou Hao-Ran Liu Fu-You Fan Si-Ming Guo jun-cheng liang De-Hong Li Yan-Ru Song Xu-Dong Ju Qiang Fu Zhi Liu Center for Transformative Science ShanghaiTech UniversityShanghai201210China Shanghai Institute of Microsystem and Information Technology Chinese Academy of SciencesShanghai200050China STAR Cryoelectronics 25-A Bisbee CourtSanta FeNM87508-1338USA Shanghai Laboratory for Particle Physics and Cosmology INPAC and Department of Physics and AstronomyShanghai Jiao Tong UniversityShanghai200240China School of Physics Beihang UniversityBeijing100191China Division of Ionizing Radiation National Institute of MetrologyNIMNo.18 Bei San Huan Dong LuChaoyang DistBeijing100029China

A transition edge sensor(TES)is extremely sensitive to changes in temperature,and combined with a high-Z metal of a certain thickness,it can realize high-energy resolution measurements of particles such as X-rays.X-rays with energies below 10 keV have a weak penetrating ability,hence,only gold or bismuth of a few micrometers in thickness can guarantee a quantum efficiency higher than 70%.Therefore,the entire structure of the TES X-ray detector in this energy range can be realized using a microfabrication ***,for X-rays or γ-rays from 10 keV to 200 keV,submillimeter absorber layers are required,which cannot be realized using the microfabrication *** paper first briefly introduces a set of TES X-ray detectors and their auxiliary systems,and then focuses on the introduction of the TES γ-ray detector with an absorber based on a submillimeter lead-tin alloy *** detector achieved a quantum efficiency above 70% near 100 keV and an energy resolution of approximately 161.5 eV at 59.5 keV.

关键词： Synchrotron radiation instrumentation X-ray spectrometers Cryogenic detectors Transition edge sensor

A compact route for efficient production of high-purity β-Ga2O3 powder

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Rare Metals 2024年第9期43卷 4573-4584页

作者： Xiao-Wei Zhou Gao-Jie Chen liang Xu Zhi-jun Shao cheng Yang Yong-Pan Tian Zhuo Zhao School of Metallurgical Engineering Anhui University of Technology Low-Carbon Research Institute Anhui University of Technology

The present study has proposed a compact process for the production of high-purity β-Ga2O3powder by simply using gallium metal and water as the raw materials. The process basically consists of two essential steps including hydrothermal synthesis of Ga OOH and calcination of Ga OOH for the production of the target product of β-Ga2O3. Thermodynamic evaluation and systematic experiments were conducted for process parameter optimization. X-ray diffractometer（XRD）, scanning electron microscopy（SEM）, thermogravimetryDdifferential scanning calorimetry（TG-DSC） and X-ray photoelectron spectroscopy（XPS） were utilized to clarify the reaction mechanisms of the hydrothermal synthesis and transformation of Ga OOH to β-Ga2O3by calcination. Chemical analysis of the final product of β-Ga2O3obtained under the optimal conditions was carried out with inductively coupled plasma mass spectrometry（ICP-MS）, and the results showed that the contents of the representative impurities such as Ni, Cu, In, Mn, Co, Zn and Cr are obviously lower than the requirement of 5N β-Ga2O3standard, exhibiting excellent application prospect of the proposed process to produce high-purity β-Ga2O3.

关键词： Calcination Hydrothermal synthesis Purity Reaction mechanism β-Ga2O3