检索结果-内蒙古大学图书馆

Performance Enhancement Mechanisms and Optimization of Multi-Pass Parallel Flow Condensers with Liquid-Vapor Separation

学校读者我要写书评

暂无评论

SSRN 2024年

作者： Pu, Jin Huan Hua, Nan Jian, Xiaodong Chen, Ying Li, Yongliang Yang, Tong Wang, Hua Sheng Shandong Institute for Advanced Technology Shandong University Shandong Jinan250061 China Ningbo Institute of Technology Beihang University Zhejiang Ningbo315832 China School of Engineering and Materials Science Queen Mary University of London LondonE1 4NS United Kingdom The Science and Technology on Reliability Physics Application of Electronic Component Laboratory The 5th Electronics Research Institute The Ministry of Industry and Information Technology Guangdong Guangzhou510610 China School of Material and Energy Guangdong University of Technology Guangdong Guangzhou510006 China School of Chemical Engineering University of Birmingham BirminghamB15 2TT United Kingdom Faculty of Science and Technology Middlesex University LondonNW4 4BT United Kingdom

This study employed a distributed-parameter model developed by the authors to investigate the mechanisms of condensation heat transfer enhancement using liquid-vapor separation (LS) in multi-pass parallel flow condensers (MPFCs). Additionally, tube pass arrangements for MPFCs with LS were optimized. Simulations characterized relationships among refrigerant flow rate, vapor quality, flow patterns, heat-transfer coefficient and pressure drop at tube level, along with heat-transfer coefficient and tube-wall temperature distributions at the segment level. An entropy analysis based on the second law of thermodynamics quantified contributions from heat transfer and pressure drop. The results demonstrate that introducing LS leads to (1) a 9.1% increase in the average heat-transfer coefficient, (2) a 50.4% reduction in pressure drop, (3) similar entropy generation numbers due to heat transfer for both MPFC and MPFC-LS, (4) significantly higher entropy generation numbers due to pressure drop in the last two tube passes, and (5) a 51.4% lower average entropy generation number for MPFC-LS compared to MPFC. Compared to a baseline serpentine condenser, MPFCs-LS reduced pressure drop by 84% to 98% while maintaining nearly the same heat transfer rate, resulting in an overall performance improvement of 5% to 9%. The optimal tube-pass arrangement for MPFCs-LS was identified as 3-3-2-2-2-2-2-1-1-1-1. © 2024, The Authors. All rights reserved.

关键词： Parallel flow

Portable Intelligent Sensor Based on Chemically Induced Silver Nanoparticles Colorimetric Response for Visual Monitoring Nitride/Sulfide Gases

学校读者我要写书评

暂无评论

SSRN 2025年

作者： Yang, Lihua Qin, Yingxi Zhao, Xiayan Liao, Dongliang Li, Fuli Jiang, Li Wen, Bo Lei, Yubin Pang, Aihua Liao, Lei Qin, Aimiao Key Laboratory of New Processing Technology for Nonferrous Metal & Materials Ministry of Education Guangxi Key Laboratory of Optical and Electronic Materials and Devices College of Material Science and Engineering Guilin University of Technology Guilin541004 China Guilin Electrical Equipment Scientific Research Institute Co. Ltd. Guilin541004 China College of Natural Resources and Environment Northwest A&F University Yangling712100 China College of Physics and Electronic Information Engineering Key Laboratory of Low-Dimensional Structural Physics and Application Education Department of Guangxi Zhuang Autonomous Region Guilin University of Technology Guilin541004 China Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology College of Environmental Science and Engineering Guilin University of Technology Guilin541004 China

Nitride/sulfide gases possess hypertoxicity and carcinogenicity. Trace H₂S/SO₂/NO₂ gases were incapable of being recognized and detected by the naked eyes in advance and caused a serious threat to human health. Based on the mechanism of chemically induced silver nanoparticles to produce colorimetric response, a paper-based colorimetric sensor array with an integrated smartphone was proposed to achieve visual detection and distinction of three trace H₂S/SO₂/NO₂ gases. The silver nanoparticles were capped by long-chain hydrophobic molecules and high molecular hydrophilic polymer and immobilized on a porous hydrophobic paper substrate, presenting excellent stability and ability to resist humidity. The fabricated sensor array exhibits excellent classifying capability, selectivity, and sensitivity for these three gases, with limits of detection (LODs) of 12.8 ppb for H2S, 131.8 ppb for SO2, and 23.1 ppb for NO2, respectively, only exposure for 5 min. Importantly, these LODs are all comfortably below their respective permissible exposure limits. TEM and density functional theory (DFT) reveal that the colorimetric responses were induced by the changes of nanoparticle morphology or size, which attributed to the electrostatic or hydrogen bonding interaction among the analytical gases, nanoparticles, and cap agents. Additionally, the fabricated sensor array integrated smartphone was capable of visually monitoring freshness of chicken during the sale. This portable intelligent colorimetric sensor based on solid-state AgNPs offers a novel approach for the continuous, ultrasensitive, rapid and visual detection of trace toxic gases and meat freshness. © 2025, The Authors. All rights reserved.

关键词： Silver nanoparticles

Threshold Voltage Instability Mechanisms of SiC Power MOSFETs under Different Gate Preconditon Durations

学校读者我要写书评

暂无评论

Threshold Voltage Instability Mechanisms of SiC Power MOSFET...

7th International Forum on Wide Bandgap Semiconductors&18th China International Forum on Solid State Lighting (第七届国际第三代半导体论坛暨第十八届中国国际半导体照明论坛)

作者： Yunliang Rao Yuan Chen Zhiyuan He Yiqiang Chen Xinbing Xu Yang Liu School of Electronics and Information Technology Sun Yat-sen University510006GuangzhouChina Scien Science and Technology on Reliability Physics and Application of Electronic Component Laboratory No. School of Electronics and Information Technology Sun Yat-sen University510006GuangzhouChina

在这项工作中，研究了不同栅极预偏置条件持续时间下SiC功率 MOSFETs的阈值电压不稳定性及其机理.这项工作中使用的SiC功率MOSFETs来自三个供应商，即某国产半导体公司、罗姆半导体和英飞凌，他们的产品分别地代表了具有平面栅极、双沟...

在这项工作中，研究了不同栅极预偏置条件持续时间下SiC功率 MOSFETs的阈值电压不稳定性及其机理.这项工作中使用的SiC功率MOSFETs来自三个供应商，即某国产半导体公司、罗姆半导体和英飞凌，他们的产品分别地代表了具有平面栅极、双沟槽栅极和非对称沟槽栅极的最先进的MOSFETs.

关键词：

High-Pressure Magnetic Properties and Electrical Transport Behaviors of Half-Metallic Ferromagnet Cro2

学校读者我要写书评

暂无评论

SSRN 2022年

作者： Zhang, Guozhao Cui, Shouxin Zhang, Haiwa Feng, Zhenbao Wang, Guangyu Wang, Qinglin Li, Yinwei Liu, Cailong Shandong Key Laboratory of Optical Communication Science and Technology School of Physical Science Information Technology of Liaocheng University Liaocheng252059 China Laboratory of Quantum Functional Materials Design and Application School of Physics and Electronic Engineering Jiangsu Normal University Xuzhou221116 China

The magnetic properties and electrical transport behaviors of half-metallic ferromagnet chromium dioxide (CrO2) powders under high pressure have been investigated by in situ electrical resistivity, magneto-resistivity and hall-effect measurements. Our results reveal that the Hall coefficient, carrier concentration and mobility all show discontinuous changes from 11.7 GPa to 14.9 GPa which can be attributed to the second-order structural transition from rutile-type to CaCl2-type. However, the resistivity decreases monotonically from ambient pressure to 16.5 GPa. This is due to, firstly, the decreased carrier concentration and the increased carrier mobility cancel the effects of each other on the resistivity;secondly, according to the calculation results, the bandgap of CrO2 decreased gradually with the pressure, and the bandgaps of rutile-type phase and CaCl2-type phase are extremely similar. CrO2 exhibits a linear and negative magnetoresistance with the applied magnetic field (0~±15 KOe). As the pressure increases, the magnetoresistance remains negative, but becomes nonlinear and less symmetry. This suggests that pressure has an appreciable impact on the double exchange mechanism leading to ferromagnetism in CrO2 . © 2022, The Authors. All rights reserved.

关键词： Chromium compounds

Nonequilibrium transport and the fluctuation theorem in the thermodynamic behaviors of nonlinear photonic systems

学校读者我要写书评

暂无评论

arXiv

arXiv 2024年

作者： Liu, Yang Lu, Jincheng Xiong, Zhongfei Wu, Fan O. Christodoulides, Demetrios Chen, Yuntian Jiang, Jian-Hua School of Physical Science and Technology Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow University 1 Shizi Street Suzhou215006 China Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application School of Physical Science and Technology Suzhou University of Science and Technology Suzhou215009 China School of Optical and Electronic Information Huazhong University of Science and Technology Wuhan430074 China CREOL College of Optics and Photonics University of Central Florida OrlandoFL32816-2700 United States Ming Hsieh Department of Electrical and Computer Engineering University of Southern California Los AngelesCA90089 United States School of Biomedical Engineering Suzhou Institute for Advanced Research University of Science and Technology of China Suzhou215123 China School of Physics University of Science and Technology of China Hefei230026 China

Nonlinear multimode optical systems have attracted substantial attention due to their rich physical properties. Complex interplay between the nonlinear effects and mode couplings makes it difficult to understand the collective dynamics of photons. Recent studies show that such collective phenomena can be effectively described by a Rayleigh–Jeans thermodynamics theory which is a powerful tool for the study of nonlinear multimode photonic systems. These systems, in turn, offer a compelling platform for investigating fundamental issues in statistical physics, attributed to their tunability and the ability to access negative temperature regimes. However, to date, a theory for the nonequilibrium transport and fluctuations is yet to be established. Here, we employ the full counting statistics theory to study the nonequilibrium transport of particle and energy in nonlinear multimode photonic systems in both positive and negative temperature regimes. Furthermore, we discover that in situations involving two reservoirs of opposite temperatures and chemical potentials, an intriguing phenomenon known as the loop current effect can arise, wherein the current in the positive energy sector runs counter to that in the negative energy sector. In addition, we numerically confirm that the fluctuation theorem remains applicable in optical thermodynamics systems across all regimes, from positive temperature to negative ones. Our findings closely align with numerical simulations based on first-principles nonlinear wave equations. Our work seeks to deepen the understanding of irreversible non-equilibrium processes and statistical fluctuations in nonlinear many-body photonic systems which will enhance our grasp of collective phenomena of photons and foster a fruitful intersection between optics and statistical physics. © 2024, CC BY-NC-ND.

关键词： Temperature

Λc(2910) and Λc(2940) as conventional baryons dressed with the D*N channel

学校读者我要写书评

暂无评论

Physical Review D 2023年第3期107卷 034036-034036页

作者： Zi-Le Zhang Zhan-Wei Liu Si-Qiang Luo Fu-Lai Wang Bo Wang Hao Xu School of Physical Science and Technology Lanzhou University Lanzhou 730000 China Research Center for Hadron and CSR Physics Lanzhou University and Institute of Modern Physics of CAS Lanzhou 730000 China Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Province and Frontiers Science Center for Rare Isotopes Lanzhou University Lanzhou 730000 China School of Physical Science and Technology Hebei University Baoding 071002 China Key Laboratory of High-precision Computation and Application of Quantum Field Theory of Hebei Province Baoding 071002 China Research Center for Computational Physics of Hebei Province Baoding 071002 China Institute of Theoretical Physics College of Physics and Electronic Engineering Northwest Normal University Lanzhou 730070 China Lanzhou Center for Theoretical Physics Lanzhou University Lanzhou 730000 China

In this work, we treat Λc(2910)+ and Λc(2940)+ as the conventional udc cores dressed with the D*N channel. We provide a possible interpretation to both Λc(2910)+ and Λc(2940)+ within the same framework. In the study, we consider not only the effects between the conventional triquark core and the D*N channel but also the D*N−D*N interactions. The mass of the Λc state with JP=1/2− is larger than that with JP=3/2− in this unquenched picture, which is very different from the prediction of the conventional quenched quark model. Based on the mass spectrum, the spin parity of Λc(2940)+ is more likely to be 1/2−, while Λc(2910)+ prefers 3/2−. We look forward to the future experiments that can test our results with more precise experimental data.

关键词： Quark model Baryons Mass

Thickness-dependent atomic structures of two-dimensional few-layer ZnO: A density functional theory study

学校读者我要写书评

暂无评论

Physical Review B 2024年第1期109卷 014105-014105页

作者： Dong Han Xian-Bin Li Nian-Ke Chen Dan Wang Sheng-Yi Xie Xue-Jiao Chen De-Zhen Shen State Key Laboratory of Luminescence and Applications Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 People's Republic of China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and Engineering Jilin University Changchun 130012 People's Republic of China School of Materials Science and Engineering Beijing Institute of Technology Beijing 100081 People's Republic of China School of Physics and Electronics Hunan University Changsha 410082 People's Republic of China CAS Key Laboratory of Magnetic Materials Devices and Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Ningbo 315201 People's Republic of China

The thickness-dependent atomic structures of two-dimensional (2D) few-layer (FL) ZnO are systematically investigated by the first-principles calculations. It is found that the structural transformation between thinner FL ZnO with graphitic structure (FL gZnO) and thicker FL ZnO with wurtzite structure (FL wZnO) takes place at the critical thickness of 9–12 Zn-O atomic layers. At the thickness of 9–12 layers, both graphitic and wurtzite structures can coexist at room temperature. In FL gZnO, the interlayer interaction is a long-range Coulomb interaction, and the charge population of Zn and O inside does not change during the structural transformation. Moreover, we demonstrate that the structural transformation of FL ZnO originates from the competition between the high energy of the O 2pz orbital in the graphitic structure and the polar-surface-induced dipole energy in the wurtzite structure. Our microscopic understanding guides a clear direction of regulating the atomic structure of FL ZnO, further optimizing its electronic properties, which benefits developing function-advanced 2D stacked devices.

关键词： Crystal structure II-VI semiconductors Multilayer thin films Density functional calculations

Surface Properties and Work Function of ZrB2 Single Crystal

学校读者我要写书评

暂无评论

SSRN 2024年

作者： Chen, Zhixuan Hao, Lingjuan Li, Chenming Gao, Qi Xu, Jun He, Julong Yuan, Zhikang Yu, Dongli Center for High Pressure Science State Key Laboratory of Metastable Materials Science and Technology Yanshan University Hebei Province Qinhuangdao066004 China Handan key Laboratory of Intelligent Awareness and Application Handan University Hebei Province Handan056001 China College of Physics and Electronic Information Luoyang Normal University Henan Province Luoyang471934 China School of Materials Engineering Shanxi College of Technology Shanxi Province Shuozhou036000 China

In this study, the surface convergence, surface energy, and work function on various crystal facets of ZrB2 were investigated by using the density functional theory calculations. Zr-terminated surface exhibits is more stable than the B-terminated surface. The electronic structure calculation reveals that ZrB2 exhibits metallic property, and the high density of states near the Fermi level is mainly composed of Zr-d and B-p orbitals. The work function values of the Zr-terminated (0001), (1010), (1120), and (11 21) surfaces of ZrB2 are 4.52, 3.83, 4.00, and 2.56 eV, respectively. We found that the surface energy and work function of ZrB2 (1121) are the lowest compared to ZrB2 (0001), (1010) and (1120) surfaces, exhibiting good surface energy stability and providing excellent electron emission performance. This work provides valuable theoretical guidance for the exploration of ZrB2 as a novel cathode material for electron emission. © 2024, The Authors. All rights reserved.

关键词： Work function

Two-party entanglement distribution in XXZ spin chains with the exponential and power-law long-range interactions

学校读者我要写书评

暂无评论

arXiv

arXiv 2025年

作者： Li, Na Zhao, Yang Ma, Wen-Long Wang, Z.D. Bai, Yan-Kui College of Physics Hebei Key Laboratory of Photophysics Research and Application Hebei Normal University Hebei Shijiazhuang050024 China State Key Laboratory of Semiconductor Physics and Chip Technologies Institute of Semiconductors Chinese Academy of Sciences Beijing100083 China Center of Materials Science and Opto-Electronic Technology University of Chinese Academy of Sciences Beijing100049 China Department of Physics HK Institute of Quantum Science & Technology Guangdong-Hong Kong Joint Laboratory of Quantum Matter The University of Hong Kong Pokfulam Road Hong Kong Quantum Science Center of Guangdong-Hong Kong-Macau Great Bay Area 3 Binlang Road Shenzhen518045 China

Entanglement distribution is a fundamental property in quantum many-body physics, but the effect of long-range interactions on the distribution has not been fully understood. Here, we study long-range two-party entanglement (TPE) and explore its distribution properties in XXZ spin chains with the exponential and power-law long-range interactions(ELRIs and PLRIs). In the thermodynamic limit case with the ELRIs, the TPE quantified by two-qubit concurrence decays exponentially along with two-site distance and the long-range concurrences can indicate the paramagnetic-ferromagnetic phase transition. We present a fine-grained entanglement distribution relations among the entanglement truncation length, total concurrences and two-tangles in the infinite spin chains. Moreover, in the finite XXZ chain with the more common PLRIs, the TPE decays algebraically along with the two-spin distance, and the total concurrence can exhibit a piecewise function with respect to total two-tangles. These new presented TPE distribution relations can be regarded as the generalization of Koashi-Bužek- and-Imoto bound for the long-range quantum models, and have potential applications in quantum information processing. © 2025, CC BY.

关键词： Quantum entanglement