检索结果-内蒙古大学图书馆

International Conference on vacuum Electronics

作者： Gennadiy Churyumov Shuang Qiu Nan-nan Wang Vacuum Electronics Department O.Ya. Usikov Institute for Radiophysics and Electronics National Academy of Science of Ukraine Kharkiv Ukraine Applied Physics Department Tsinghua University Beijing China Microwave Engineering Department Harbin Institute of Technology Harbin China

This paper presents the theoretical and experimental results of the studies of the new designs of the magnetrons known as the magnetrons with two energy outputs (or dual-output magnetrons). The prototypes of the two magnetrons for X and Ku-bands are developed. The magnetrons produce the average maximum powers of ~ 18.6 W and ~ 15.5 W, frequency tuning of ~ 220 MHz and ~ 150 MHz, and frequency stability of $(3\ldots 5)10^{-6}$ , respectively. The results of computer modeling of the W-band magnetron are presented. Examples of applying the dual-output magnetrons in radar systems and communication are given.

关键词：

来源：评论

学校读者我要写书评

暂无评论

A Spiral Graphene Framework Containing Highly Ordered Graphene Microtubes for Polymer Composites with Superior Through-Plane Thermal Conductivity

引用

Chinese Journal of Chemistry 2022年第3期40卷 329-336页

作者： Jinrui Gong Xue Tan Qilong Yuan Zhiduo Liu Junfeng Ying Le Lv Qingwei Yan Wubo Chu Chen Xue Jinhong Yu Kazuhito Nishimura Nan Jiang Cheng-Te Lin Wen Dai Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and Engineering(NIMTE)Chinese Academy of SciencesNingboZhejiang 315201China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBejjing 100049China Centre for Quantum Physics Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement(MOE)Beijing Key Lab of Nonophotonics&Ultrafine Optoelectronic SystemsSchool of PhysicsBeijing Institute of TechnologyBeijing 100081China College of Materials Science and Engineering Hunan UniversityChangshaHunan 410082China Advanced Nano-processing Engineering Lob Mechanical Systems EngineeringKogakuin UniversityTokyo 192-0015Japan

As the power density of electronic devices increases,there has been an urgent demand to develop highly conductive polymer composites to address the accompanying thermal management *** to the ultra-high intrinsic thermal conductivity,graphene is considered a very promising filler to improve the thermal conductivity of ***,graphene-based polymer composites prepared by the conventional mixing method generally have limited thermal conductivity,even under high graphene loading,due to the failure to construct efficient heat transfer pathways in the polymer ***,a spiral graphene framework(SGF)containing continuous and highly ordered graphene microtubes was developed based on a modified CVD *** embedding into the epoxy(EP)matrix,the graphene microtubes can act as efficient heat pathways,endowing the SGF/EP composites with a high through-plane thermal conductivity of 1.35 W·m^(-1)·K^(-1) at an ultralow graphene loading of 0.86 wt%.This result gives a thermal conductivity enhancement per 1 wt%filler loading of 710%,significantly outperforming various graphene structures as *** addition,we demonstrated the practical application of the SGF/EP composite as a thermal interface material for efficient thermal man-agement of the light-emitting diode(LED).

关键词： Graphene Chemical vapor deposition Polymer Thermal conductivity Thermal management material

来源：评论

学校读者我要写书评

暂无评论

Simple yet clear local evidence for the tetrahedral triple-Q magnetic ground state in the triangular antiferromagnet Co1/3NbS2

引用

Physical Review B 2024年第9期109卷 094401-094401页

作者： Yiwen Dong Bo Zhang Yantao Cao Hanjie Guo Wei Ren Anmin Zhang ZhenHua Li Zhengqing Wei Haoliang Liu Liyun Tang Hua Pang Fashen Li Zhiwei Li Key Lab for Magnetism and Magnetic Materials of the Ministry of Education School of Physical Science and Technology Lanzhou University Lanzhou 730000 Gansu China Songshan Lake Materials Laboratory Dongguan 523808 Guangdong China Lanzhou Center for Theoretical Physics Key Laboratory of Quantum Theory and Applications of MOE Key Laboratory of Theoretical Physics of Gansu Province Lanzhou University Lanzhou 730000 Gansu China Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems School of Science Harbin Institute of Technology (Shenzhen) Shenzhen 518055 China

In this work, we demonstrate a simple yet effective procedure for identifying the exotic tetrahedral triple-Q magnetic ordering over the domain averaged collinear single-Q magnetic state for the triangular antiferromagnet Co1/3NbS2. Our density functional theory (DFT) calculations show that the hyperfine magnetic field exhibits a significant anisotropic dependence on the angle between the spin direction and the c-axis, which means that the atoms with different spin directions in the triple-Q state can be divided into two subgroups with a ratio of 1:3 that can be distinguished by local probing methods. Mössbauer spectroscopy measurements on (Co0.99Fe0.0157)1/3NbS2 crystals confirm exactly our DFT predictions and thus give possible evidence of the tetrahedral triple-Q magnetic state. These results provide important insights into the magnetic ground state of Co1/3NbS2, which shall shed light on the understanding of the anomalous Hall effect in Co1/3NbS2 and other related materials.

关键词： Magnetic order Micromagnetism 2-dimensional systems Antiferromagnets Chiral magnets Noncollinear magnets Single crystal materials Density functional theory Mössbauer spectroscopy

来源：评论

学校读者我要写书评

暂无评论

Hybrid Dirac semimetal-based photodetector with efficient low-energy photon harvesting

引用

Light(science & Applications) 2022年第3期11卷 107-116页

作者： Lin Wang Li Han Wanlong Guo Libo Zhang Chenyu Yao Zhiqingzi Chen Yulu Chen Cheng Guo Kaixuan Zhang Chia-Nung Kuo Chin Shan Lue Antonio Politano Huaizhong Xing Mengjie Jiang Xianbin Yu Xiaoshuang Chen Wei Lu State Key Laboratory for Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of Sciences500 Yu-tian RoadShanghai 200083China Department of Optoelectronic Science and Engineering Donghua UniversityShanghai 201620China College of Physics and Optoelectronic Engineering Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesNo.1Sub-Lane XiangshanXihu DistrictHangzhou 310024China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China The 50th Research Institute of China Electronics Technology Group Shanghai 200331China Research Center for Intelligent Network Zhejiang LabHangzhou 311121China Department of Physics Cheng Kung University1 Ta-Hsueh Road70101 TainanTaiwanChina INSTM and Department of Physical and Chemical Sciences University of L’Aquilavia Vetoio67100 L’Aquila(AQ)Italy CNR-IMM Istituto per la Microelettronica e Microsistemi VIII strada 5I-95121 CataniaItaly

Despite the considerable effort,fast and highly sensitive photodetection is not widely available at the low-photon-energy range(~meV)of the electromagnetic spectrum,owing to the challenging light funneling into small active areas with efficient conversion into an electrical ***,we provide an alternative strategy by efficiently integrating and manipulating at the nanoscale the optoelectronic properties of topological Dirac semimetal PtSe_(2)and its van der Waals ***,we realize strong plasmonic antenna coupling to semimetal states near the skin-depth regime(λ/10^(4)),featuring colossal photoresponse by in-plane symmetry *** observed spontaneous and polarization-sensitive photocurrent are correlated to strong coupling with the nonequilibrium states in PtSe_(2)Dirac semimetal,yielding efficient light absorption in the photon range below 1.24 meV with responsivity exceeding∼0.2 A/W and noise-equivalent power(NEP)less than~38 pW/Hz^(0.5),as well as superb ambient *** results pave the way to efficient engineering of a topological semimetal for high-speed and low-energy photon harvesting in areas such as biomedical imaging,remote sensing or security applications.

关键词： stability Dirac topological

来源：评论

学校读者我要写书评

暂无评论

Defect Passivation and Carrier Management Via a Multifunctional Additive for Efficient and Stable Wide-Bandgap Perovskite Solar Cells with High Fill Factor

SSRN

引用

SSRN 2024年

作者： Guo, Yaxiong Du, Shengjie Hu, Xuzhi Li, Guang Yu, Zhixi Guan, Hongling Wang, Shuxing Jia, Peng Zhou, Hai Li, Chun Ke, Weijun Fang, Guojia International School of Microelectronics Dongguan University of Technology Dongguan523808 China Key Lab of Artifcial Micro- and Nano-Structures of Ministry of Education of China School of Physics and Technology Wuhan University Wuhan430072 China School of Optoelectronic Science and Engineering University of Electronic Science and Technology of China Chengdu610054 China School of Electronic and Electrical Engineering Wuhan Textile University Wuhan430200 China

Wide-bandgap (WBG) Methylammonium (MA)-free based perovskite solar cells (PSCs) have attracted widespread research interests due to their broad applicability in multijunction tandem. Nevertheless, the efficiency of WBG PSCs is restricted by unfulfilled potential in fill factor and large deficits in open-circuit voltage. The imbalanced carrier mobility not only plays a critical role in bulk non-radiative recombination loss but also hinders efficient charge collection for mixed I/Br WBG perovskites. Herein, we introduced additive named 2,8-Diiododibenzothiophene to overcome above issues. Inverted devices with enhanced photostability and a record fill factor of 85.7% are demonstrated. Moreover, combining the semitransparent WBG PSCs with 1.25 eV-bandgap perovskite bottom cells, we realized 4-terminal tandem devices and a champion PCE of 28% is achieved. The multifunctional additive strategy demonstrated here, will open new avenues for improving WBG PSCs’ performance. © 2024, The Authors. All rights reserved.

关键词： Perovskite

来源：评论

学校读者我要写书评

暂无评论

Growth,coalescence,and etching of two-dimensional overlayers on metals modulated by near-surface Ar nanobubbles

引用

Nano Research 2022年第3期15卷 2706-2714页

作者： Wei Wei Jiaqi Pan Haiping Lin Chanan Euaruksakul Zhiyun Li Rong Huang Li Wang Zhujun Wang Qiang Fu Yi Cui Vacuum Interconnected Nanotech Workstation Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123China Synchrotron Light Research Institute Nakhon Ratchasima 30000Thailand School of Physical Science and Technology Shanghai Tech UniversityShanghai 200031China Scientific Center for Optical and Electron Microscopy ETH Zürich8093 ZürichSwitzerland State Key Laboratory of Catalysis iChEMDalian Institute of Chemical Physicsthe Chinese Academy of SciencesDalian 116023China

The synthesis of high-quality ultrathin overlayers is critically dependent on the surface structure of substrates,especially involving the overlayer–substrate *** using in situ surface measurements,we demonstrate that the overlayer–substrate interaction can be tuned by doping near-surface Ar *** interfacial coupling strength significantly decreases with near-surface Ar nanobubbles,accompanying by an“anisotropic to isotropic”growth *** the substrate containing near-surface Ar,the growth front crosses entire surface atomic steps in both uphill and downhill directions with no difference,and thus,the morphology of the two-dimensional(2D)overlayer exhibits a ***,the round-shaped 2D overlayers coalesce seamlessly with a growth acceleration in the approaching direction,which is barely observed in the synthesis of 2D *** can be attributed to the immigration lifetime and diffusion rate of growth species,which depends on the overlayer–substrate interaction and the surface ***,the“round to hexagon”morphological transition is achieved by etching-regrowth,revealing the inherent growth kinetics under quasi-freestanding *** findings provide a novel promising way to modulate the growth,coalescence,and etching dynamics of 2D materials on solid surfaces by adjusting the strength of overlayer–substrate interaction,which contributes to optimization of large-scale production of 2D material crystals.

关键词： two dimensional materials overlayer–substrate interaction near-surface Ar nanobubbles evolution behavior surface dynamics

来源：评论

学校读者我要写书评

暂无评论

Role of Water in Methanol Photochemistry on TiO₂Nanocrystals: An in Situ DRIFTS Study

引用

Journal of Physical Chemistry C 2022年第20期126卷 8615-8626页

作者： Fu, Cong Zhang, Yunshang Sun, Xiao Fang, Fei Huang, Weixin Hefei National Research Center for Physical Science at the Microscale Key Lab. of Surf. and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes Department of Chemical Physics University of Science and Technology of China Hefei 230026 China Dalian National Laboratory for Clean Energy Chinese Academy of Sciences Dalian 116023 China

Effects of adsorbed water on methanol photochemistry on TiO2surfaces is an interesting and important issue. In this paper, we have studied coadsorption and photochemistry of water and methanol on TiO2nanocrystals with... 详细信息

Effects of adsorbed water on methanol photochemistry on TiO₂surfaces is an interesting and important issue. In this paper, we have studied coadsorption and photochemistry of water and methanol on TiO₂nanocrystals with different predominantly exposed facets using in situ diffuse-reflectance infrared spectroscopy and an isotope labeling technique. Preadsorbed water on TiO₂exerts versatile influences on methanol photochemistry. Water competes with methanol for surface sites on TiO₂;meanwhile, surface OH groups are capable of assisting methanol decomposition to methoxy species. Surface OH groups can trap photoexcited electrons, which open up photocatalytic reactions of adsorbed methanol species in the absence of O₂;moreover, the acquiring surface ^•OH radicals can directly participate in photocatalytic conversions of adsorbed methanol species. In the presence of O₂, water influences photocatalytic oxidation of adsorbed methanol species on TiO₂NCs mainly by affecting methanol and O₂adsorption. All these effects vary sensitively with exposed facets and surface structures of TiO₂nanocrystals. These results unveil the complex nature of influences of adsorbed water on methanol photochemistry on TiO₂surfaces. © 2022 American Chemical Society. All rights reserved.

关键词： Adsorption Alcohols Electromagnetic radiation Oxidation Oxides

来源：评论

学校读者我要写书评

暂无评论

Machine learning in laser-induced breakdown spectroscopy:A review

引用

Frontiers of physics 2024年第6期19卷 225-252页

作者： Zhongqi Hao Ke Liu Qianlin Lian Weiran Song Zongyu Hou Rui Zhang Qianqian Wang Chen Sun Xiangyou Li Zhe Wang Key Laboratory of Nondestructive Testing(Ministry of Education) Nanchang Hangkong UniversityNanchang 330063China Wuhan National Laboratory for Optoelectronics(WNLO) Huazhong University of Science and TechnologyWuhan 430074China State Key Lab of Power System Department of Energy and Power EngineeringTsinghua-BP Clean Energy CentreTsinghua UniversityBeijing100084China School of Optics and Photonics Beijing Institute of TechnologyBeijing 100081China School of Physics and Astronomy Shanghai Jiao Tong UniversityShanghai 200240China School of Public Health Xinjiang Medical UniversityUrumqi 830054China The Second Medical College of Binzhou Medical University Yantai Affiliated Hospital of Binzhou Medical UniversityYantai264100China School of Electronic Engineering Naval University of EngineeringWuhan 430014China

Laser-induced breakdown spectroscopy(LIBS)is a spectroscopic analytic technique with great application potential because of its unique advantages for online/in-situ ***,due to the spatially inhomogeneity and drastically temporal varying nature of its emission source,the laser-induced plasma,it is difficult to find or hard to generate an appropriate spatiotemporal window for high repeatable signal collection with lower matrix *** quantification results of traditional physical principle based calibration model are unsatisfactory since these models were not able to compensate for complicate matrix effects as well as signal *** learning is an emerging approach,which can intelligently correlated the complex LIBS spectral data with its qualitative or/and quantitative composition by establishing multivariate regression models with greater potential to reduce the impacts of signal fluctuation and matrix effects,therefore achieving rela-tively better qualitative and quantitative *** this review,the progress of machine learning application in LIBS is summarized from two main aspects:(i)Pre-processing data for machine learning model,including spectral selection,variable reconstruction,and denoising to improve qualitative/quantitative performance;(ii)Machine learning methods for better quantification performance with reduction of the impact of matrix effect as well as LIBS spectra *** review also points out the issues that researchers need to address in their future research on improving the performance of LIBS analysis using machine learning algorithms,such as restrictions on training data,the disconnect between physical principles and algorithms,the low generalization ability and massive data processing ability of the model.

关键词： laser-induced breakdown spectroscopy machine learning repeatability matrix effects qualitative and quantitativeanalysis

来源：评论

学校读者我要写书评

暂无评论

The Lithosphere Structure and its Implication for Different Metallogenic Belts beneath the Eastern South China Block

引用

Acta Geologica Sinica(English Edition) 2024年第S01期98卷 2-5页

作者： CHEN Changxin LÜQingtian CHEN Ling SHI Danian YAN Jiayong AI Yinshuang Chinese Academy of Geological Sciences Beijing 100037China SinoProbe Center Chinese Academy of Geological Sciences and China Geological SurveyBeijing 100037China China MNR Lab of Deep Earth Science and Technology Beijing 100094China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China CAS Center for Excellence in Deep Earth Science Guangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The South China Block(SCB)was formed through the Neoproterozoic amalgamation of the Yangtze Block(YB),the Cathaysia Block(CB),and the accreted components of the Jiangnan orogenic belt(JNO),it is bounded by the Jiangshan–Shaoxing–Pingxiang fault(JSPF)and the Jiujiang–Shitai–Jishou fault(JSJF)(Yao et al.,2019).The SCB has undergone a series of complex geological events,including Paleozoic orogeny,Mesozoic collisions with the North China Craton(NCC)and the Indochina Block,as well as the intracontinental orogeny,leading to extensive lithospheric modifications and magmatic activities(Zhang H J et al.,2023;Fig.1).

关键词： lithosphere structure receiver function mineral system South China Block

来源：评论

学校读者我要写书评

暂无评论

Polar and layered wide-bandgap semiconductors WO2Cl2 and MoO2Br2 with giant birefringence, large second harmonic and ferroelectric photovoltaic effects

引用

Physical Review B 2024年第15期109卷 155421-155421页

作者： Hao Huo Xiao Jiang Lei Kang Functional Crystals Lab Key Laboratory of Functional Crystals and Laser Technology Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China Beijing Computational Science Research Center Beijing 100193 China

van der Waals (vdW) layered semiconductors exhibiting large nonlinear-optical (NLO) effects have substantial potential for developing nanoscale quantum optical devices. NbOCl2, an ultrathin quantum light source, has recently displayed a large second harmonic effect. However, its small bandgap (∼1.8 eV) impedes transparent light conversion across wide spectral regions, especially when utilizing practical 1-µm lasers. In this paper, we found that MO2X2 (M=W, Mo; X=Cl, Br) effectively widens the bandgap by using W6+ or Mo6+ instead of Nb4+ to eliminate in-gap nonbonding orbitals. Meanwhile, the octahedral [MO4X2] motifs display polar Jahn-Teller distortions as large as [NbO2X4] to demonstrate comparable NLO polarization effects. Based on first-principles calculations, WO2Cl2 and MoO2Br2 are predicted to possess wider bandgaps (2.9 and 2.2 eV), giant birefringence (0.5–0.7), and significant second harmonic and ferroelectric photovoltaic effects competitive with NbOX2. These findings provide strong incentives to explore new vdW materials with superior NLO properties.

关键词： Jahn-Teller effect Nonlinear optics Optoelectronics

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：