检索结果-内蒙古大学图书馆

Electronegative warm plasma and material interaction under secondary electron emission

Materials Today: Proceedings 2022年 65卷 3483-3487页

作者： Prasad Jha, Yetendra Malik, Mayand Kumar, Mayank Malik, Hitendra K. Plasma Science and Technology Laboratory Department of Physics Indian Institute of Technology Delhi New Delhi 110016 India School of Engineering Indian Institute of Technology Mandi Himachal Pradesh Mandi 175075 India Department of Mechanical Engineering Indian Institute of Technology Delhi New Delhi 110016 India

Plasma-material interaction is examined in an electronegative warm plasma under secondary electron emission from the wall. The sheath formed during the interaction is evaluated and its thickness is compared for three different plasmas (C60plasma, Oxygenplasma and CF4,plasma) and the sheath thickness is found to be maximum in C60plasma and minimum in Oxygenplasma. The sheath potential, floating potential, and sheath thickness decrease when the secondary electrons are present in larger number. The density of secondary electrons increases with higher number of the negative ions at the sheath edge as well as inside the sheath for various values of density of multi-charged negative ions. © 2022

关键词： Negative ions

来源：评论

学校读者我要写书评

暂无评论

A Wideband Frequency Division Duplex High Temperature Resistant Antenna Based on Open-Ended Waveguide

A Wideband Frequency Division Duplex High Temperature Resist...

引用

IEEE International Conference on Electronics and Communication Engineering (ICECE)

作者： Cheng Zhang Jing-yang Sun Jian-yan Liu Hong-wei Deng College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics Nanjing China Science and Technology on Space Physics Laboratory Beijing China

ISBN: (数字)9798331517755

ISBN: (纸本)9798331517762

In this paper, a wideband frequency division duplex (FDD) high temperature resistant open-ended waveguide antenna with wide beam performance is designed. The antenna uses two coaxial probes to feed vertically at adjacent sides of the open-ended waveguide, enabling the antenna to achieve high isolation duplex communication with perpendicular polarization directions in different frequency bands. At the same time, the open-ended waveguide antenna with a metal floor is placed under thermal insulation material to realize high temperature resistance performance. The thermal protection shield is fixed to the metal floor through screws and filled with thermal insulation material. The simulation results show that the FDD high-temperature resistant antenna can achieve wide beam radiation from 3.5GHz to 4.5 GHz and 7GHz to 9 GHz, respectively. Under the continuous temperature of 1200°C for 2000s, the temperature at two feed ports is kept below 150°C.

关键词： Resistance Insulation Simulation Metals Directive antennas Frequency conversion Broadband antennas Probes Wideband Floors

来源：评论

学校读者我要写书评

暂无评论

Cryo-CMOS Model-Enabled 8-bit 32 MS/s SAR ADC with Split Capacitor Array

Cryo-CMOS Model-Enabled 8-bit 32 MS/s SAR ADC with Split Cap...

引用

Electronic Information Engineering and Computer Communication (EIECC), International Conference on

作者： Yajie Huang Changchun Zhou Guoping Guo Chao Luo Department of Physics University of Science and Technology of China Hefei China Department of Physics Hefei National Laboratory University of Science and Technology of China Hefei China

ISBN: (数字)9798331534622

ISBN: (纸本)9798331534639

This article presents a cryogenic 8-bit successive approximation register (SAR) analog-to-digital converter (ADC) using Nexchip 110 nm 1P6M CMOS technology for the readout of qubits. To mitigate the base freeze-out effect of bipolar junction transistors at cryogenic temperature and the resulting unavailable BJT-based bandgap voltage reference circuits, a VCM -based switching procedure through a capacitive DAC with top-plate sampling split capacitor array was employed. By the adoption of compact cryo-CMOS SPICE model and asynchronous control logic, the ADC achieves an SNDR of 41.56 dB and consumes 2.1 mW while maintaining the Walden FoM of 646 fJ/conv.-step at 4.2 K and 32 MS/s. The converter occupies an active area of 0.106 mm 2 .

关键词： Computers Power measurement Capacitors Qubit Cryogenics SPICE Registers Transistors Integrated circuit modeling Switching circuits

来源：评论

学校读者我要写书评

暂无评论

Effects of partial Eu filling in the unfilled skutterudite CoP3

引用

Physical Review B 2024年第3期110卷 035156-035156页

作者： Zicheng Tao Chao Zhang Jian Yuan Renjie Zhang Xia Wang Zhenhai Yu Wei Xia Yaobo Huang Shihao Zhang Yanfeng Guo School of Physical Science and Technology Tsung-Dao Lee Institute Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Beijing 100049 China Analytical Instrumentation Center School of Physical Science and Technology ShanghaiTech Laboratory for Topological Physics Shanghai 201210 China Shanghai Advanced Research Institute Shanghai Institute of Applied Physics School of Physics and Electronics

The unfilled skutterudite CoP3 hosts extremely large magnetoresistance (∼2 × 104% at 30 T and 2 K), large hole mobility (∼2 × 104 cm2V−1s−1, 2 K), and a fourfold quadratic contact point (QCP) above the Fermi level in the electronic structure. We unveil herein that the partial filling of Eu onto the icosahedral void sites of CoP3 can shift the QCP to lie below the Fermi level while retaining the high carrier mobility (∼1.6 × 104 cm2V−1s−1, 2 K). Unlike nonmagnetic CoP3, partially filled skutterudite Eu0.412Co4P12 is a soft ferromagnet with almost isotropic magnetism. Additionally, an intriguing topological Hall effect is observed, likely hinting an unusual spin texture. In this paper, we provide useful insights into the interplay between magnetism and the nontrivial feature of the electronic band structure, which would guide more efforts in studying this issue.

关键词： Magnetotransport Topological materials Skutterudites

来源：评论

学校读者我要写书评

暂无评论

Meteorological influences on co-occurrence of O_(3) and PM_(2.5)pollution and implication for emission reductions in Beijing-Tianjin-Hebei

引用

science China Earth sciences 2023年第6期66卷 1258-1267页

作者： Xiaoqing MA Zhicong YIN Bufan CAO Huijun WANG Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Co-occurrence of surface ozone(O_(3))and fine particulate matter(PM_(2.5))pollution(CP)was frequently observed in Beijing-Tianjin-Hebei(BTH).More than 50%of CP days occurred during April-May in BTH,and the CP days reached up to 11 in two months of *** PM_(2.5)or O_(3) concentration associated with CP was lower than but close to that in O_(3) and PM_(2.5)pollution,indicating compound harms during CP days with double-high concentrations of PM_(2.5)and O_(3).CP days were significantly facilitated by joint effects of the Rossby wave train that consisted of two centers associated with the Scandinavia pattern and one center over North China as well as a hot,wet,and stagnant environmental condition in *** 2018,the number of CP days decreased sharply while the meteorological conditions did not change ***,changes in meteorological conditions did not really contribute to the decline of CP days in 2019 and *** implies that the reduction of PM_(2.5)emission has resulted in a reduction of CP days(about 11 days in 2019 and 2020).The differences in atmospheric conditions revealed here were helpful to forecast the types of air pollution on a daily to weekly time *** reduction in PM_(2.5)emission was the main driving factor behind the absence of CP days in 2020,but the control of surface O_(3) must be stricter and deeper.

关键词： Co-occurrence pollution Ozone PM_(2.5) Meteorology Emission reduction

来源：评论

学校读者我要写书评

暂无评论

Plasmon-mediated photodecomposition of NH3 via intramolecular charge transfer

引用

Nano Research 2022年第5期15卷 3894-3900页

作者： Yimin Zhang Weite Meng Daqiang Chen Lili Zhang Shunfang Li Sheng Meng Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China Key Laboratory of Material Physics Ministry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450001China School of Chemical Engineering Anhui University of Science and TechnologyHuainan 232000China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China

As an excellent clean medium for hydrogen storage and fuel cell applications,the photolysis of ammonia via localized surface plasmon could be invoked as a promising route towards significantly reducing the temperature for conventional ***,we explore the underlying microscopic mechanism of ultrafast carrier dynamics in plasmon-mediated NH3 photodecomposition at the single-molecular level using real-time time-dependent density functional *** NH_(3)molecule adsorbed on the tip of archetypal magic metal clusters represented by tetrahedral Ag_(2)0 and icosahedral Ag147,splits within a hundred femtoseconds upon laser pulse *** found that the splitting of the first N-H bond is dominated by the intramolecular charge transfer driven by localized surface ***,the phase of laser pulse could modulate the dynamics of charge transfer and thus affect the plasmon-induced bond *** findings offer a new avenue for NH3 decomposition and provide in-depth insights in designing highly efficient plasmon-mediated photocatalysts.

关键词： ammonia photodecomposition localized surface plasmon intramolecular charge transfer time-dependent density functional theory

来源：评论

学校读者我要写书评

暂无评论

Balancing sub‐reaction activity to boost electrocatalytic urea synthesis using a metal‐free electrocatalyst

引用

Carbon Energy 2023年第10期5卷 40-49页

作者： Chen Chen Shuang Li Xiaorong Zhu Shuowen Bo Kai Cheng Nihan He Mengyi Qiu Chao Xie Dezhong Song Youzhen Liu Wei Chen Yafei Li Qinghua Liu Conggang Li Shuangyin Wang State Key Laboratory of Chem/Bio‐Sensing and Chemometrics Advanced Catalytic Engineering Research Center of the Ministry of EducationCollege of Chemistry and Chemical EngineeringHunan UniversityChangshaChina College of Chemistry and Materials Science Nanjing Normal UniversityNanjingChina National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefeiChina Key Laboratory of Magnetic Resonance in Biological Systems State Key Laboratory of Magnetic Resonance and Atomic and Molecular PhysicsNational Center for Magnetic Resonance in Wuhan Collaborative Innovation Center of Chemistry for Life SciencesWuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhanChina

Electrocatalytic urea synthesis via coupling of nitrate with CO_(2)is considered as a promising alternative to the industrial urea synthetic ***,the requirement of sub-reaction(NO_(3)RR and CO_(2)RR)activities for efficient urea synthesis is not clear and the related reaction mechanisms remain ***,the construction,breaking,and rebuilding of the sub-reaction activity balance would be accompanied by the corresponding regulation in urea synthesis,and the balance of sub-reaction activities was proven to play a vital role in efficient urea *** rational design,a urea yield rate of 610.6 mg h−1 gcat.−1 was realized on the N-doped carbon electrocatalyst,superior to that of noble-metal *** on the operando SRFTIR measurements,we proposed that urea synthesis arises from the coupling of^(*)NO and^(*)CO to generate the key intermediate of^(*)*** work provides new insights and guidelines into urea synthesis from the aspect of activity balance.

关键词： activity balance C-N coupling electrocatalysis metal‐free urea synthesis

来源：评论

学校读者我要写书评

暂无评论

A vacuum ultraviolet laser with a submicrometer spot for spatially resolved photoemission spectroscopy

引用

Light(science & Applications) 2021年第3期10卷 371-378页

作者： Yuanhao Mao Dong Zhao Shen Yan Hongjia Zhang Juan Li Kai Han Xiaojun Xu Chuan Guo Lexian Yang Chaofan Zhang Kun Huang Yulin Chen College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangshaHunan 410073China Department of Optics and Optical Engineering University of Science and Technology of ChinaHefeiAnhui 230026China College of Intelligence Science and Technology National University of Defense TechnologyChangshaHunan 410073China State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Department of Physics Clarendon LaboratoryUniversity of OxfordOxfordUK School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

Vacuum ultraviolet(VUV)lasers have demonstrated great potential as the light source for various spectroscopies,which,if they can be focused into a small beam spot,will not only allow investigation of mesoscopic materials and structures but also find application in the manufacture of nano-objects with excellent *** this work,we report the construction of a 177 nm VUV laser that can achieve a record-small(〜0.76 μm)focal spot at a long focal length(~45 mm)by using a flat lens without spherical *** size of the beam spot of this VUV laser was tested using a metal grating and exfoliated graphene flakes,and we demonstrated its application in a fluorescence spectroscopy study on pure and Tm3+-doped NaYF4 microcrystals,revealing a new emission band that cannot be observed in the traditional up-conversion *** addition,this laser system would be an ideal light source for spatially and angleresolved photoemission spectroscopy.

关键词： laser ultraviolet spatially

来源：评论

学校读者我要写书评

暂无评论

Possible molecules of triple-heavy pentaquarks within the extended local hidden gauge formalism

引用

Physical Review D 2024年第7期110卷 076014页

作者： Zhong-Yu Wang Chu-Wen Xiao Zhi-Feng Sun Xiang Liu School of Physical Science and Technology Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu Province and Key Laboratory of Quantum Theory and Applications of the Ministry of Education Department of Physics Guangxi Key Laboratory of Nuclear Physics and Technology School of Physics MoE Frontiers Science Center for Rare Isotopes Research Center for Hadron and CSR Physics

In this study, we explore the interactions between mesons and baryons in the open heavy sectors to identify potential triple-heavy molecular pentaquarks. We derive the meson-baryon interaction potentials using the vector meson exchange mechanism within the extended local hidden gauge formalism. The scattering amplitudes are computed by solving the coupled-channel Bethe-Salpeter equation, revealing several bound systems. By analyzing the poles of these amplitudes in the complex plane, we determine the masses and widths of these bound states. Additionally, we evaluate the couplings and compositeness of different channels within each bound system to assess their molecular characteristics. Our predictions include 4 Ωccc-like states, 4 Ωbbb-like states, 14 Ωbcc-like states, and 10 Ωbbc-like states, which could be targets for future experimental investigations.

关键词： Bethe-Salpeter equation Effective field theory Multiquark bound states Particle interactions

来源：评论

学校读者我要写书评

暂无评论

Kinetic analysis and modeling of maize straw hydrochar combustion using a multi-Gaussian-distributed activation energy model

引用

International Journal of Minerals,Metallurgy and Materials 2022年第3期29卷 464-472页

作者： Chunmei Yu Shan Ren Guangwei Wang Junjun Xu Haipeng Teng Tao Li Chunchao Huang Chuan Wang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Department of Physics University of Science and Technology BeijingBeijing 100083China Swerim AB LuleåSE-97125Sweden Thermal and Flow Engineering Laboratory Åbo Akademi UniversityÅbo FI-20500Finland

Combustion kinetics of the hydrochar was investigated using a multi-Gaussian-distributed activation energy model(DAEM)to ex-pand the knowledge on the combustion *** results demonstrated that the kinetic parameters calculated by the multi-Gaussian-DAEM accurately represented the experimental conversion rate ***,the feedstock combustion could be divided into four stages:the decomposition of hemicellulose,cellulose,lignin,and char *** hydrochar combustion could in turn be divided into three stages:the combustion of cellulose,lignin,and *** mean activation energy ranges obtained for the cellulose,lignin,and char were 273.7-292.8,315.1-334.5,and 354.4-370 kJ/mol,respectively,with the standard deviations of 2.1-23.1,9.5-27.4,and 12.1-22.9 kJ/mol,*** cellulose and lignin contents first increased and then decreased with increasing hydrothermal carbonization(HTC)temperature,while the mass fraction of char gradually increased.

关键词： hydrothermal carbonization maize straw combustion kinetics distributed activation energy model

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：