检索结果-内蒙古大学图书馆

Effect of order–disorder transition on thermodynamic and electronic properties of σ and χ phases in W–Re alloy: the first-principles calculation

引用

Tungsten 2025年第1期7卷 195-213页

作者： Zhi-Peng Zhu Dian Jia William Yi Wang Jun-Lei Yin Xing-Yu Gao Shu-Feng Yang Hai-Feng Song Jin-Shan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The Tungsten-Rhenium(W-Re) alloys,celebrated for their high melting point,strength at elevated temperatures,electrical resistivity,and radiation resistance,have been widely utilized in high-temperature components,aerospace,electronics,and nuclear *** constituents of the topologically close-packed(TCP) phases,the sigma phase(σ) and chi phase(χ) formed within W-Re alloys wield considerable influence on the mechanical properties and the stability of the *** calculations were utilized in the present work to explore the structural,thermodynamic,and electronic properties of both ordered and disordered configurations within the σ and χ phases,culminating in a systematic elucidation of the higher phase stability exhibited by the ordered *** is found that the bulk modulus of these two phases is directly proportional to the concentration of Re in the alloy,while the equilibrium volume is inversely *** thermodynamic parameters of the σ and χ phases are calculated via the mean-field potential *** similar trends observed in the isobaric heat capacity,enthalpy increment,and entropy change curves for these two phases suggest they possess comparable thermodynamic *** is noteworthy that the contribution of ionic vibrations predominantly affects the isobaric heat capacity,while the contribution of thermal electronic excitations increases linearly with *** the structure and thermodynamic properties of TCP phases in W-Re alloys at low temperatures has profound significance for optimizing material performance,microstructures features,establishing theoretical foundations,and predicting material behavior.

关键词： First-principles calculations Phase stability Thermodynamic properties W-Re alloy TCP phases

来源：评论

学校读者我要写书评

暂无评论

Review of bumper materials for spacecraft shield against orbital debris hypervelocity impact

引用

Defence technology(防务技术) 2025年第3期45卷 137-177页

作者： Siyuan Ren Pinliang Zhang Qiang Wu Qingming Zhang Zizheng Gong Guangming Song Renrong Long Liangfei Gong Mingze Wu Beijing Institute of Spacecraft Environment Engineering China Academy of Space TechnologyBeijing100094China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China School of Civil Engineering Chongqing Jiaotong UniversityChongqing400074China

It is widely known that the hypervelocity impact of orbital debris can cause serious damage to spacecraft,and enhancing the impact resistance is the great concern of spacecraft shield *** paper provides a comprehensive overview of advances in the development of bumper materials for spacecraft shield *** particular,the protective mechanism and process of the bumper using different materials against hypervelocity impact are reviewed and *** advantages and disadvantages of each material used in shield were discussed,and the performance under hypervelocity impact was given according to the specific *** review provides the useful reference and basis for researchers and engineers to create bumper materials for spacecraft shield applications,and the contemporary challenges and future directions for bumper materials for spacecraft shield were presented.

关键词： Orbital debris spacecraft shield Hypervelocity impact Bumper materials Protective mechanism

来源：评论

学校读者我要写书评

暂无评论

M^(2)CS:A microwave measurement and control system for large-scale superconducting quantum processors

引用

Chinese physics B 2024年第12期33卷 67-78页

作者： Jiawei Zhang Xuandong Sun Zechen Guo Yuefeng Yuan Yubin Zhang Ji Chu Wenhui Huang Yongqi Liang Jiawei Qiu Daxiong Sun Ziyu Tao Jiajian Zhang Weijie Guo Ji Jiang Xiayu Linpeng Yang Liu Wenhui Ren Jingjing Niu Youpeng Zhong Dapeng Yu Shenzhen Institute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518048China International Quantum Academy Shenzhen 518048China Guangdong Provincial Key Laboratory of Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518048China Department of Physics Southern University of Science and TechnologyShenzhen 518048China Shenzhen Branch Hefei National LaboratoryShenzhen 518048China

As superconducting quantum computing continues to advance at an unprecedented pace,there is a compelling demand for the innovation of specialized electronic instruments that act as crucial conduits between quantum processors and host ***,we introduce a microwave measurement and control system(M^(2)CS)dedicated to large-scale superconducting quantum processors.M^(2)CS features a compact modular design that balances overall performance,scalability and *** tests of M^(2)CS show key metrics comparable to commercial *** tests on transmon superconducting qubits further show qubit coherence and gate fidelities comparable to state-of-the-art results,confirming M^(2)CS's capability to meet the stringent requirements of quantum experiments running on intermediate-scale quantum *** compact and scalable nature of our design holds the potential to support over 1000 qubits after upgrade in stability and *** M^(2)CS architecture may also be adopted to a wider range of scenarios,including other quantum computing platforms such as trapped ions and silicon quantum dots,as well as more traditional applications like microwave kinetic inductance detectors and phased array radar systems.

关键词： superconducting quantum computation superconducting qubit arbitrary waveform generator(AWG) data acquisition board(DAQ)

来源：评论

学校读者我要写书评

暂无评论

Characteristic Mode Analysis for Thin Dielectric Sheets with Alternative Surface Integral Equation

引用

Chinese Journal of Electronics 2022年第6期31卷 1181-1188页

作者： JIA Chunlai HE Zi DING Dazhi GUAN Ling AI Xia LIU Jiaqi CHEN Xuewen Department of Communication Engineering Nanjing University of Science and Technology Science and Technology on Electromagnetic Scattering Laboratory Beijing Institute of Environmental Features National Key Laboratory of Science and Technology on Test Physics and Numerical Mathematics School of Physics and Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology

When the dielectric sheet is electrically thin in the normal direction, the conventional volume integral equation(VIE) can be approximately simplified to the surface one. On this basis, a novel surface integral equation-based formulation is presented for analyzing characteristic mode(CM) of thin dielectric sheets. The resultant CMs are expressed with tangential and normal components of electric volume currents, which are more intuitive than the conventional VIE-based one. Due to the application of volume equivalence principle, the proposed formulation is immune to non-physical modes. The CMs of typical thin dielectric bodies, including the dielectric substrate and radome, are analyzed to show that the proposed formulation is computationally efficient with encouraging accuracy.

关键词： normal components alternative surface integral equation thin dielectric sheets normal direction electric volume currents dielectric sheet radome radomes dielectric bodies surface integral equation-based formulation volume equivalence principle thin dielectric bodies tangential components nonphysical modes electromagnetic wave scattering conventional volume integral equation integral equations characteristic mode analysis dielectric substrate

来源：评论

学校读者我要写书评

暂无评论

The Multi-parameter Test of Gravitational Wave Dispersion with Principal Component Analysis

引用

Research in Astronomy and Astrophysics 2024年第5期24卷 140-150页

作者： Zhi-Chu Ma Rui Niu Wen Zhao CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

In this work, we consider a conventional test of gravitational wave(GW) propagation which is based on the phenomenological parameterized dispersion relation to describe potential departures from General Relativity(GR)along the propagation of GWs. But different from tests conventionally performed previously, we vary multiple deformation coefficients simultaneously and employ the principal component analysis(PCA) method to remedy the strong degeneracy among deformation coefficients and obtain informative posteriors. The dominant PCA components can be better measured and constrained, and thus are expected to be more sensitive to potential departures from the waveform model. Using this method we analyze ten selected events and get the result that the combined posteriors of the dominant PCA parameters are consistent with GR within 99.7% credible intervals. The standard deviation of the first dominant PCA parameter is three times smaller than that of the original dispersion parameter of the leading order. However, the multi-parameter test with PCA is more sensitive to not only potential deviations from GR but also systematic errors of waveform models. The difference in results obtained by using different waveform templates hints that the demands of waveform accuracy are higher to perform the multiparameter test with PCA. Whereas, it cannot be strictly proven that the deviation is indeed and only induced by systematic errors. It requires more thorough research in the future to exclude other possible reasons in parameter estimation and data processing.

关键词： gravitational waves-gravitation-black hole physics

来源：评论

学校读者我要写书评

暂无评论

Nonanalytic magnetic response and intrinsic ferromagnetic clusters in a kagome spin-liquid candidate

引用

Physical Review B 2024年第12期110卷 L121105页

作者： B. S. Shivaram Joseph C. Prestigiacomo Aini Xu Zhenyuan Zeng Trevor D. Ford Itamar Kimchi Shiliang Li Patrick A. Lee Department of Physics Materials Science and Technology Division School of Physical Sciences Beijing National Laboratory for Condensed Matter Physics School of Physics Dongguan Guangdong 523808 China

Finding distinct signatures of a quantum spin liquid (QSL) is an ongoing quest in condensed matter physics, invariably complicated by the presence of disorder in real materials. In this regard the two-dimensional kagome system YCu3(OH)6[(ClxBr(1−x))3−y(OH)y] (YCOB−Cl), where the vast mismatch in size of Y and Cu avoids substitutional disorder, otherwise present in kagome materials, has emerged as a favorable candidate. In crystals of this system, with x<0.4 and no long-range order, we report an unusual field-dependent magnetization M(B), where M/B changes linearly with |B|, the absolute value of the field, in contrast to the expected quadratic behavior. Model calculations with a distribution of ferromagnetic (FM) clusters faithfully capture the observed features. YCOB-Cl exhibits a field-enhanced T2 heat capacity expected in certain spin-liquid models. However, a concomitant linear T behavior in the spin susceptibility has been lacking. Our work suggests that FM clusters, by dominating the contribution to the susceptibility, mask the true underlying behavior.

关键词： Exotic phases of matter Fractionalization Magnetic order Magnetic susceptibility Methods in magnetism Quantum phase transitions Spin dynamics Spinon

来源：评论

学校读者我要写书评

暂无评论

Photophysics of metal-organic frameworks:A brief overview

引用

Chinese physics B 2024年第1期33卷 122-133页

作者：刘晴硕余俊宏胡建波 State Key Laboratory for Environment-Friendly Energy Materials Southwest University of Science and TechnologyMianyang 621010China Laboratory for Shock Wave and Detonation Physics Institute of Fluid PhysicsChina Academy of Engineering PhysicsMianyang 621900China

Metal-organic frameworks(MOFs),which are self-assembled porous coordination materials,have garnered considerable attention in the fields of optoelectronics,photovoltaic,photochemistry,and photocatalysis due to their diverse structures and excellent ***,the performance of MOF-based optoelectronic applications currently falls short of the industry *** enhance the performance of MOF materials,it is imperative to undertake comprehensive investigations aimed at gaining a deeper understanding of photophysics and sequentially optimizing properties related to photocarrier transport,recombination,interaction,and *** utilizing femtosecond laser pulses to excite MOFs,time-resolved optical spectroscopy offers a means to observe and characterize these ultrafast microscopic *** approach adds the time coordinate as a novel dimension for comprehending the interaction between light and ***,this review provides a comprehensive overview of the recent advancements in the photophysics of MOFs and additionally outlines potential avenues for exploring the time domain in the investigation of MOFs.

关键词： metal-organic framework(MOF) ultrafast spectroscopy photophysics carrier dynamics

来源：评论

学校读者我要写书评

暂无评论

Site selective 5f electronic correlations inβ-uranium

引用

Chinese physics B 2023年第1期32卷 421-426页

作者：邱睿智谢刘桦黄理 Institute of Materials China Academy of Engineering PhysicsMianyang 621907China School of Physical Science and Technology Southwest UniversityChongqing 400715China Science and Technology on Surface Physics and Chemistry Laboratory Mianyang 621908China

We investigate the electronic structure ofβ-uranium,which has five nonequivalent atomic sites in its unit cell,by means of the density functional theory plus Hubbard-U correction with U from linear response *** is found that the 5f electronic correlations inβ-uranium are *** interestingly,their strengths are site selective,depending on the local atomic environment of the present uranium *** a consequence,the occupation matrices and partial 5f density of states ofβ-uranium manifest site *** addition,the complicate experimental structure ofβ-uranium could be well reproduced within this theoretical framework.

关键词： uranium low-symmetry crystal structure 5f electronic correlation site-selectivity density-functional theory

来源：评论

学校读者我要写书评

暂无评论

Thermal and ignition properties of hexanitrostilbene(HNS) microspheres prepared by droplet microfluidics

引用

Defence technology（防务技术） 2023年第7期25卷 166-173页

作者： Rui-shan Han Fei-peng Lu Fang Zhang Yan-lan Wang Mi Zhou Guo-sheng Qin Jian-hua Chen Hai-fu Wang En-yi Chu State Key Laboratory of Explosion and Technology Beijing Institute of TechnologyBeijing100081China Science and Technology on Applied Physical Chemistry Laboratory Shaanxi Applied Physics-Chemistry Research InstituteXi'an710061ShaanxiChina

HNS-IV(Hexanitrostilbene-IV) is the main charge of the exploding foil initiators(EFI), and the microstructure of the HNS will directly affect its density, flowability, sensitivity, and stability. HNS microspheres were prepared using droplet microfluidics, and the particle size, morphology, specific surface area, thermal performance, and ignition threshold of the HNS microspheres were characterized and tested. The results shown that the prepared HNS microspheres have high sphericity, with an average particle size of 20.52 μm(coefficient of variation less than 0.2), and a specific surface area of 21.62 m^(2)/g(6.87 m^(2)/g higher than the raw material). Without changing the crystal structure and thermal stability of HNS-IV, this method significantly enhances the sensitivity of HNS-IV to short pulses and reduces the ignition threshold of the slapper detonator to below 1000 V. This will contribute to the miniaturization and low cost of EFI.

关键词： Microfluidics HNS microspheres Thermal stability Ignition threshold

来源：评论

学校读者我要写书评

暂无评论

Ultralow-Temperature Heat Transport in Quantum Spin Liquid Candidates:A Brief Review

引用

Chinese physics Letters 2024年第12期41卷 173-180页

作者： Na Li Xia Zhao Xue-Feng Sun Anhui Provincial Key Laboratory of Magnetic Functional Materials and Devices Institutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601China School of Physics Sciences University of Science and Technology of ChinaHefei 230026China

Heat in solids can be transported by various quasiparticles, making low-temperature heat transport a powerfultool for probing charge-neutral excitations in quantum materials. In recent years, ultralow-temperature heattransport has been instrumental in detecting exotic excitations in quantum spin liquids (QSLs). A non-zeroresidual thermal conductivity, κ0/T, serves as compelling evidence for the presence of itinerant spinons andthe gapless nature of a disordered state. Additionally, the thermal Hall effect (THE) in QSLs can arise fromcontributions by spinons or Majorana fermions. In this review, we summarize key thermal conductivity findingsfrom various QSL candidates, focusing on the role of spinons in both heat transport and phonon *** also examine different experimental observations and the underlying mechanisms of THE in QSL candidateswith three-dimensional pyrochlore structures, as well as two-dimensional honeycomb and triangular lattices. Thisreview offers valuable insights and guidance for understanding ultralow-temperature heat transport in QSLs.

关键词： excitation quantum triangular

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：