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Influence and determinative factors of ion-to-atom arrival ratio in unbalanced magnetron sputtering systems 被引量:8
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作者 Jun Zhou Zhe Wu Zhanhe Liu 《Journal of University of Science and Technology Beijing》 CSCD 2008年第6期775-781,共7页
Low pressure sputtering with a controlled ratio of ion flux to deposited atom flux at the condensing surface is one of the main directions of development of magnetron sputtering methods. Unbalanced magnetron sputterin... Low pressure sputtering with a controlled ratio of ion flux to deposited atom flux at the condensing surface is one of the main directions of development of magnetron sputtering methods. Unbalanced magnetron sputtering, by producing dense secondary plasma around the substrate, provides a high ion current density. The closed-field unbalanced magnetron sputtering system (CFUBMS) has been established as a versatile technique for high-rate deposition high-quality metal, alloy, and ceramic thin films. The'key factor in the CFUBMS system is the ability to transport high ion currents to the substrate, which can enhance the formation of full dense coatings at relatively low value homologous temperature. The investigation shows that the energy of ions incidenced at the substrate and the ratio of the flux of these ions to the flux of condensing atoms are the fundamental parameters in determining the structure and properties of films produced by ion-assisted deposition processes. Increasing ion bombardment during deposition combined with increasing mobility of the condensing atoms favors the formation of a dense microstructure and a smooth surface. 展开更多
关键词 magnetron sputtering closed-field unbalanced magnetron sputtering system (CFUBMS) ion-to-atom ratio unbalancedmagnetron sputtering
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Experimental study of cross-section ratios in the collisions of C^(q+) and O^(q+) (q=1-4) on atomic helium in strong-interaction region 被引量:1
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作者 陈熙萌 江丽娟 +12 位作者 周鹏 周春林 高志民 邱玺玉 崔莹 王兴安 娄凤君 吕学阳 贾娟娟 陈林 邵剑雄 吕瑛 王幡 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期322-327,共6页
We have measured the cross-section ratios of helium induced by Cq+ and Oq+ (q = 1-4) in an energy range from 20 keV/amu to 500 keV/amu, and obtained the two-dimensional spectra by employing the coincidence method ... We have measured the cross-section ratios of helium induced by Cq+ and Oq+ (q = 1-4) in an energy range from 20 keV/amu to 500 keV/amu, and obtained the two-dimensional spectra by employing the coincidence method combined with the MPA-3 data acquisition system. Hence, we obtain the ratios of total single-ionization cross-sections (SI, SC, SLSI, and DLSI), total double-ionization cross-sections (DI, DC, TI, SLDI, and DLDI) and cross-sections of every process (SI, SC, SLSI, DLSI, DI, DC, TI, SLDI, and DLDI), which induce the single-ionization and double-ionization, to the total cross sections respectively. The competitive relations between the reaction-channels and the experimental data law of each reaction-channel are revealed explicitly, and the qualitative explanations involved in those results are also presented accordingly. 展开更多
关键词 ion-atom collisions strong-interaction region cross-section ratios competitive relation
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Ground-based Investigations of Atomic Oxygen Erosion Behaviors of Silver and Ion-implanted Silver 被引量:2
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作者 DUO Shu-wang LI Mei-shuan +2 位作者 YIN Xiao-hui LI Wen-kui LI Ming-sheng 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第B12期252-256,共5页
Silver foils and ion-implanted silver foils exposed to atomic oxygen (AO) generated in a ground simulation facility were investigated by the quartz crystal microbalance (QCM), the scanning electron microscopy (SE... Silver foils and ion-implanted silver foils exposed to atomic oxygen (AO) generated in a ground simulation facility were investigated by the quartz crystal microbalance (QCM), the scanning electron microscopy (SEM) and the X-ray photoelectron spectroscopy (XPS). The experimental results show the presence of Ag2O and AgO in an oxidation process of the silver foil having exposure to AO. As soon as silver comes under the bombardment of atomic oxygen, the oxidation process starts with a thick film forming on the silver surface. Because of the development of stresses, the oxide layer gets cracked and spalled, which leads to appearance of a new silver surface intensifying further oxidation. At last, AgO begins to form on the outer surface of the oxide film. The analytical results of the XPS and the AES attest to formation of a continuous high-quality protective oxide-based layer on the surface of ion-implanted silver films after exposure to AO. This layer can well protect materials in question from erosion. 展开更多
关键词 atomic oxygen ion-implantation SILVER OXIDATion
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On-line Preconcentration and Determination of Trace Metals in Water Samples by Flow Injection Combined with Flame Atomic Absorption Spectrometry via Calix[4]arene Carboxylic Acid Packed Micro-column 被引量:1
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作者 GUO Da-wang, ZHAO Xiao-wei, JIA Qiong and ZHOU Wei-hong College of Chemistry, Jilin University, Changchun 130012, P. R. China 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第1期26-30,共5页
An adsorbent calix[4]arene carboxylic acid was employed as the adsorption material for on-line flow in jection(FI) micro-column preconcentration coupled with flame atomic absorption spectrometry(FAAS) determinatio... An adsorbent calix[4]arene carboxylic acid was employed as the adsorption material for on-line flow in jection(FI) micro-column preconcentration coupled with flame atomic absorption spectrometry(FAAS) determination of trace heavy metals(Cu, Pb, Co, Ni and Cd). Parameters such as the pH, loading time and flow rate of sample, and the concentration, volume and flow rate of eluent were optimized. The enrichment factors are 50.0, 56.5, 11.6, 12.1 and 19.1 for Cu, Pb, Co, Ni, and Cd, respectively, and a sample throughput of 20 h–1 was obtained. The limits of de tection for Cu, Pb, Co, Ni, and Cd were in a range of 1.56―3.91 μg/L, and the relative standard deviations(RSDs) were less than 2.76%(n=7). Furthermore, the proposed method was successfully applied to the determination of Cu, Pb, Co, Ni, and Cd in certified reference materials and various water samples. 展开更多
关键词 arene carboxylic acid PRECONCENTRATion Flow injection Metal ion Flame atomic absorptionspectrometry(FAAS)
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ACCELERATOR-BASED ATOMIC PHYSICS AT THE LAWRENCE BERKELEY LABORATOTY:COLLISIONS OF FAST,HIGHLY-CHARGED IONS WITH ATOMS
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作者 AlfredS.Schlachter 《Nuclear Science and Techniques》 SCIE CAS CSCD 1990年第Z1期32-39,共8页
Research on accelerator-based atomic physics at the Lawrence Berkeley Laboratory super-HILAC and Bevalac accelerators is described. This research covers several important topics in collisions of fast, highly charged i... Research on accelerator-based atomic physics at the Lawrence Berkeley Laboratory super-HILAC and Bevalac accelerators is described. This research covers several important topics in collisions of fast, highly charged ions with atoms: charge transfer, ionization, and excitation. Multiple - electron processes are emphasized. Electron correlation is important in some of these processes, e.g., resonance transfer and excitation (RTE) multiple-electron capture in close collisions. A variety of experiments and results for energies from 1 to 420 MeV/u are presented. 展开更多
关键词 ACCELERATOR atomIC physics COLLISionS of ionS with atomS
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EXPERIMENTS OF MeV ION BEAM INDUCED ATOMIC MIXING
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作者 赵国庆 任月华 +2 位作者 周筑颖 汤国魂 汤家镛 《Nuclear Science and Techniques》 SCIE CAS CSCD 1990年第3期143-148,共6页
An experimental apparatus for studies of MeV ion beam modification of materials has been established on a 3 MV tandem accelerator at Fudan university. A system of X-Y electrostatic scanning implantation of MeV heavy i... An experimental apparatus for studies of MeV ion beam modification of materials has been established on a 3 MV tandem accelerator at Fudan university. A system of X-Y electrostatic scanning implantation of MeV heavy ions and in situ Rutherford. backscattering analysis was included in it. The uniformity of scanning implantation was checked by the RBS measurement of a Si wafer implanted with 1 MeV Au ions. MeV ion beam mixing of Au/Si, Au/Ge and Ag/Si systems was preliminarily studied. The samples were irradiated by certain fluences of 1 MeV Ag ions at room temperature. The mixed layers were analyzed in situ using the glancing RBS technique with 2 MeV 4He+ ions. For Au/Si system, a uniformly mixed layer with a defined composition is obtained, and the intermixing is much less for Ag/Si system than for Au/Si system. 展开更多
关键词 MEV Ag+ ionS atomIC MIXING Au/Si Au/Ge and Ag/Si systems
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Intrinsic Decoherence of a Two-Atom System with Dipole-Dipole Interaction
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作者 齐琳娜 朱爱东 张寿 《Chinese Physics Letters》 SCIE CAS CSCD 2008年第4期1183-1186,共4页
We investigate the effect of dipole-dipole interaction on the intrinsic decoherence of a system which consists of two two-level atoms and an optical cavity. The entanglement of the system is calculated by making use o... We investigate the effect of dipole-dipole interaction on the intrinsic decoherence of a system which consists of two two-level atoms and an optical cavity. The entanglement of the system is calculated by making use of concurrence. Our results show that the appropriate choice for the coupling constant Ω of dipole-dipole interaction can restrain the intrinsic deeoherenee of the system. We also find a special phenomenon. No matter what the value of γ is, the concurrence of system slowly increases and cannot exceed 0.71 when Ω= 1. 展开更多
关键词 JAYNES-CUMMINGS MODEL TRAPPED ion 2 atomS ENTANGLEMENT CAVITY WAVE
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Comparison of Simulation Methods of Ion-Atomic Collisions in PIC-MC
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作者 Valeriy Sysun Alexander Sysun +2 位作者 Vladimir Ignakhin Viktor Titov Alexander Tikhomirov 《Journal of Applied Mathematics and Physics》 2014年第13期1233-1241,共9页
The main ion-atomic collision treatment methods based on Monte-Carlo simulation are considered and discussed. We have proposed an efficient scheme for simulation of time between collisions taking into account cross-se... The main ion-atomic collision treatment methods based on Monte-Carlo simulation are considered and discussed. We have proposed an efficient scheme for simulation of time between collisions taking into account cross-section dependence on ion velocity and random generation of ion velocities and scattering angles after collisions. The developed algorithm of simulation of interval between collisions takes into account the change of relative velocity of ion-atom pair as well as the change of cross-section of collision and atomic concentration. At the same time, unlike the widely used “null-collision” method, both the probability of collision and change of particles’ state which determines this probability are taken into consideration for each particle independently in time. The simulation results according to the techniques proposed are found to be close to the theoretical values of ion drift velocities. It is revealed that the “null-collision” method results in exceeding of drift velocity in strong and intermediate fields. At the same time the proposed method of accumulation of probability under the same conditions gives values close to theoretical ones. In weak fields calculated values of drift velocity in both methods exceed theoretical values to some small extent. 展开更多
关键词 PIC-MC Simulation ion-atomic COLLISionS DISCHARGE Plasma
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THE STUDIES OF SURFACE LAYER ATOMIC STRUCTURE OF AL(100) BY MEV ION SCATTERING
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作者 承焕生 崔志祥 +2 位作者 徐洪杰 要小未 杨福家 《Nuclear Science and Techniques》 SCIE CAS CSCD 1990年第Z1期105-112,共8页
A UHV system specially designed for studying surface and interface atomic structure by MeV ion scattering and channeling is described. The vacuum in the UHV chamber is 133.332×10-10Pa. The chamber is equipped wit... A UHV system specially designed for studying surface and interface atomic structure by MeV ion scattering and channeling is described. The vacuum in the UHV chamber is 133.332×10-10Pa. The chamber is equipped with an ion gun used for sample cleaning, a translatable four-grid LEED-Auger system used for characterization of the crystal surface, and a three dimensional goniometer. The crystal preparation and cleaning procedure of Al(100) are presented. The surface peak intensity of Al(100)-【100】 and Al(100)- 【100】 has been measured by MeV ion channeling and scattering. The measured surface peak intensity was compared with that of Monte-Carlo simulation. The experimental results indicate that the thermal vibration amplitude of Al(100) surface atoms is 1.2 -1.3 times that of bulk atoms. The relaxation of first layer for Al(100) is less than -0.005nm. 展开更多
关键词 MEV ion SCATTERING Surface LAYER atomIC structure AL
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Semiclassical Approach to Non-Sequential Double Ionization of Diatomic Molecules in Strong Laser Field
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作者 刘杰 陈京 《Chinese Physics Letters》 SCIE CAS CSCD 2006年第1期91-94,共4页
We develop a semiclassical model to describe the non-sequential double ionization of diatomic molecules in an intense linearly polarized field, achieving insight into the two-electron correlation effect in the ionizat... We develop a semiclassical model to describe the non-sequential double ionization of diatomic molecules in an intense linearly polarized field, achieving insight into the two-electron correlation effect in the ionization dynamics. Compared to the experimental data of nitrogen molecules, our model shows a good agreement in the tunnelling regime and a qualitative agreement in the over-barrier regime. We find that the classical collisional trajectories are the main source of the double ionization in the tunnelling regime. As a prediction of our theory, we also calculate the double ionization ratios of H2^2+/H2^+ for hydrogen molecules and predict a ratio less than that of nitrogen molecules. 展开更多
关键词 HELIUM PULSES atomS DEPENDENCE MECHANISM DYNAMICS ionS
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Numerical Investigation of the Tri-Atomic Ions Formation during Laser Ionization Based on Resonance Saturation
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作者 M. A. Abdelati M. A. Mahmoud Y. E. E. Gamal 《Journal of Applied Mathematics and Physics》 2014年第12期1123-1129,共7页
We present a theoretical investigation of plasma generation in sodium vapor induced by laser radiation tuned to the first resonance line (3S-3P) at λ = 589 ns. A set of rate equations that describe the rate of change... We present a theoretical investigation of plasma generation in sodium vapor induced by laser radiation tuned to the first resonance line (3S-3P) at λ = 589 ns. A set of rate equations that describe the rate of change of the ground and excited states population as well as the temporal variation of the electron energy distribution function (EEDF), beside the formed atomic ion Na+, molecular ion ?and tri-atomic ions are solved numerically. The calculations are carried out at different laser energy and different sodium atomic vapor densities under the experimental conditions of Tapalian and Smith (1993) to test the existence of the formed tri-atomic ions. The numerical calculations of the electron energy distribution function (EEDF) show that a deviation from the Maxwellian distribution due to the super elastic collisions effect. In addition to the competition between associative ionization (3P-3P), associative ionization (3P-3D) and Molnar-Horn- beck ionization processes for producing , the calculations have also shown that the atomic ions Na+ are formed through the Penning ionization and photoionization processes. These results are found to be consistent with the experimental observations. 展开更多
关键词 Plasma Laser COLLISionAL ionIZATion Association ionIZATion Tri-atomic ions PHOTOionIZATion Electron Energy Distribution Function
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Modified Atomic Orbital Theory of the O+ Ion Originating from 2D0 and 4S0 Metastable States
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作者 Malick Sow Fatou Ndoye +3 位作者 Babou Diop Alassane Traoré Abdou Diouf Boubacar Sow 《Journal of Applied Mathematics and Physics》 2022年第6期1873-1886,共14页
We report in this paper energy positions of the 2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>F);2D<sup>0</sup>_2s<... We report in this paper energy positions of the 2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>F);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>D);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>P);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)ns(<sup>2</sup>D);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>3</sup>(<sup>3</sup>D)np(<sup>2</sup>P);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>3</sup>(<sup>3</sup>D<sup>0</sup>)np(<sup>2</sup>F), and 4S<sup>0</sup>_2s<sup>2</sup>2p<sup>3</sup>(<sup>5</sup>S<sup>0</sup>)np(<sup>4</sup>P) Rydberg series in the photoionization spectra originating from 2D<sup>0</sup> and 4S<sup>0</sup> metastable states of O<sup>+</sup> ion. Calculations are performed up to n = 20 using the Modified Orbital Atomic Theory (MAOT) [1]. The present results are compared to the experimental data of Aguilar et al. [2] which are the only available values. The accurate data presented in this work may be a useful guideline for future experimental and other theoretical studies. 展开更多
关键词 Semiempirical Calculations Modified Orbital atomic Theory Electron Correlation Calculations atoms and ions Rydberg Series Quantum Defect
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Motion Characteristics of Single Electrons of Atoms of Atomic Gas of Hydrogen and Single Electrons of Hydrogen-Like Ions in Form Gas or Vapour during Decays of Such Atoms and Ions. Emission Line Spectra
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作者 Ivan Antonovych Strilets 《Journal of Modern Physics》 2014年第14期1302-1320,共19页
For the first time the vector differential equation of central motion of single electron in electric field of an atomic nucleus as in external central electric field is set up and solved. Here the following findings a... For the first time the vector differential equation of central motion of single electron in electric field of an atomic nucleus as in external central electric field is set up and solved. Here the following findings are reported. Each of single electrons of a part of atoms of atomic gas of hydrogen and a part of hydrogen-like ions in the form of a gas or a vapour revolves around corresponding atomic nucleus in a flat spiral which has an interior maximum of turns density. The distance between each of these single electrons and corresponding atomic nucleus increases while a speed of single electron decreases. Such motion of single electrons takes place with no expenditures of external energy and points to decays of foregoing parts of atoms and ions. The electric field strength of the atomic nuclei of atoms of atomic gas of hydrogen and hydrogen-like ions in the form of a gas or a vapour is inversely proportional to the distance between the atomic nucleus and the corresponding single electron by greater than the power of 3. Calculated cyclic frequency (rough value 3.5×1014 s-1) of revolution of the electron around the nucleus of atom of atomic gas of hydrogen (in interior maximum of turns density of the flat spiral), which moves at speed 2.2×106 ms-1, and central cyclic frequency of α-line of Balmer series (4.5×1014 s-1) have the same order of magnitude. This fact and line structure of experimental emission line spectra confirm the formation of all lines of these spectra by continuous slight emission of light front by single electrons. The formation of series of lines of emission line spectra is linked to repeated creations of atoms of atomic gas of hydrogen and hydrogen-like ions in the form of a gas or a vapour. 展开更多
关键词 atomic GAS of HYDROGEN Hydrogen-Like ionS Slight EMISSion of Light Front by Single Electron EMISSion Line Spectra
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Determination of Atomic Fraction of Isotope Carbon-13 Directly in Urea, Benzophenone, Nitrobenzene, Benzoic Acid and 2-Hydroxybenzoic Acid
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作者 Lamzira Parulava Levani Eliashvili +1 位作者 Vakhtang Betlemidze Natia Mzareulishvili 《American Journal of Analytical Chemistry》 2022年第6期195-205,共11页
The possibility of determining atomic fractions of the isotopes of carbon directly in urea, nitrobenzene, benzophenone, benzoic acid and 2-Hydroxybenzoic acid in compounds isotopically modified by all carbon centers, ... The possibility of determining atomic fractions of the isotopes of carbon directly in urea, nitrobenzene, benzophenone, benzoic acid and 2-Hydroxybenzoic acid in compounds isotopically modified by all carbon centers, as well as by one or several identical carbon centers is considered. The mass peaks of the mass spectrum that allows determining the atomic fraction of carbon isotopes are selected. The respective formulas are proposed. Until now, isotope analysis of these compounds has been carried out by converting them to carbon monoxide or dioxide, and it has been impossible to determine the atomic fraction of carbon at individual centers. 展开更多
关键词 atomic Fraction Isotopically Modified Centers Monoisotopic Form Molecular ions Mass Spectrometer Mass Spectrum
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深化普通化学教学中对离子晶体的认识
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作者 聂晶晶 方文军 《大学化学》 2025年第1期362-368,共7页
晶体分类是普通化学课程的基本内容之一。本文展现了不同离子晶体中阴、阳离子间的相互作用包含了离子键、氢键或范德华力等类型,说明“离子晶体是阴、阳离子通过离子键结合而成”的表述并不合适。因此,在普通化学教学中,需要重新审视... 晶体分类是普通化学课程的基本内容之一。本文展现了不同离子晶体中阴、阳离子间的相互作用包含了离子键、氢键或范德华力等类型,说明“离子晶体是阴、阳离子通过离子键结合而成”的表述并不合适。因此,在普通化学教学中,需要重新审视离子晶体的定义和离子间相互作用类型对离子晶体的熔、沸点等性质的影响。 展开更多
关键词 原子间距 离子间相互作用 离子键 氢键 范德华力
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Z=6—51间类锂离子等电子序列激发能及辐射跃迁速率
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作者 赵嘉勋 武晨晟 宋庆和 《物理学报》 北大核心 2025年第15期151-168,共18页
本文基于多组态Dirac-Fock方法(multi-configuration Dirac-Fock,MCDF)和组态相互作用方法(configuration interaction,CI)系统计算了类锂等电子序列Z=6-51间C^(3+),F^(6+),Mg^(9+),P^(12+),Ar^(15+),Sc^(18+),Cr^(21+),Co^(24+),Zn^(27... 本文基于多组态Dirac-Fock方法(multi-configuration Dirac-Fock,MCDF)和组态相互作用方法(configuration interaction,CI)系统计算了类锂等电子序列Z=6-51间C^(3+),F^(6+),Mg^(9+),P^(12+),Ar^(15+),Sc^(18+),Cr^(21+),Co^(24+),Zn^(27+),As^(30+),Kr^(33+),Y^(36+),Mo^(39+),Rh^(42+),Cd^(45+),Sn^(37+),Sb^(38+)共17种离子1s2nl(n≤4,l≤3)对应的15个能级激发能以及能级间的所有电偶极(E1)、磁偶极(M1)和电四极(E2)跃迁速率.将所得计算结果与NIST数据库及先前的一些理论结果进行对比,当前的绝大部分激发能计算结果与NIST数据的差异在0.02%以内,且显著优于先前同样采用MCDF+CI方法得到的理论结果.而大部分跃迁速率计算结果与NIST数据的差异亦在5%以内,部分与NIST数据差异较大的激发能以及跃迁速率数据,当前的结果与先前同样采用MCDF+CI方法得到的理论结果相符,这一结果提示未来需对这些跃迁进行更加深入的理论和实验研究.本研究可为未来天体和实验室等离子体的实验诊断和理论模拟提供了精确的数据支撑. 展开更多
关键词 类锂离子 原子结构 多组态DIRAC-FOCK方法 辐射跃迁速率
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电子/离子成像技术在冷原子分子及相关领域中的应用
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作者 刘洋 沈镇捷 +1 位作者 王新成 江玉海 《物理学报》 北大核心 2025年第15期80-97,共18页
随着激光冷却原子分子技术和全空间电子离子成像技术的日益成熟与发展,运用动量成像技术研究冷原子特征属性和碰撞动力学是一个新兴方向,并且发展了一系列高分辨的电子离子探测装置,在冷分子反应、里德伯原子、核衰变、玻色-爱因斯坦凝... 随着激光冷却原子分子技术和全空间电子离子成像技术的日益成熟与发展,运用动量成像技术研究冷原子特征属性和碰撞动力学是一个新兴方向,并且发展了一系列高分辨的电子离子探测装置,在冷分子反应、里德伯原子、核衰变、玻色-爱因斯坦凝聚光电离与冷等离子体、冷原子与离子/电子碰撞、冷原子相干控制、强场超快等研究方向取得一系列创新成果.本文综述了相关领域具有代表性的仪器以及相应的重要成果,最后对成像技术在冷原子上述各相关研究领域中的应用进行相应的总结,并展望了未来的发展趋势. 展开更多
关键词 电子/离子成像 冷原子 磁光阱速度成像谱仪 磁光阱反应显微成像谱仪
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金属单原子在钠离子电容器中的应用进展
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作者 张文武 张熊 +3 位作者 李晨 孙现众 王凯 马向东 《石油化工高等学校学报》 2025年第1期1-10,共10页
钠离子电容器是一种兼具钠离子电池和双电层电容器特点的新型储能器件。然而,钠离子电容器正负极动力学不匹配会导致其功率密度低、循环稳定性差。自单原子催化剂概念出现以来,由于其具备强大的催化活性、高原子效率、高选择性和稳定性... 钠离子电容器是一种兼具钠离子电池和双电层电容器特点的新型储能器件。然而,钠离子电容器正负极动力学不匹配会导致其功率密度低、循环稳定性差。自单原子催化剂概念出现以来,由于其具备强大的催化活性、高原子效率、高选择性和稳定性,因此在储能器件领域受到广泛关注。首先,阐述了钠离子电容器电极材料所面临的挑战,分析了钠离子电容器的储能机制;其次,介绍了单原子催化剂的特性和碳载金属单原子材料的制备方法;然后,总结了金属单原子材料在钠离子电容器中的应用进展;最后,对金属单原子在钠离子电容器中的应用前景进行了展望。 展开更多
关键词 钠离子电容器 单原子催化剂 金属单原子 合成方法
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碳原子和离子轫致辐射过程中电子屏蔽效应研究
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作者 闫彤 刘爱华 焦利光 《物理学报》 北大核心 2025年第3期40-50,共11页
轫致辐射作为原子物理中重要的辐射过程,在天体物理、等离子体物理、磁约束和惯性约束核聚变等领域具有重要研究意义.本文基于相对论分波展开方法研究了中高能电子碰撞中性碳原子以及各价态碳离子的轫致辐射过程,并探讨电子屏蔽效应对... 轫致辐射作为原子物理中重要的辐射过程,在天体物理、等离子体物理、磁约束和惯性约束核聚变等领域具有重要研究意义.本文基于相对论分波展开方法研究了中高能电子碰撞中性碳原子以及各价态碳离子的轫致辐射过程,并探讨电子屏蔽效应对轫致辐射截面及角分布的影响.利用Dirac-Hartree-Fock理论构建靶原子波函数,在中心场近似下建立电子-靶原子相互作用势,基于相对论分波展开方法通过数值求解Dirac方程得到电子连续态波函数,对不同价态碳离子的轫致辐射单重、双重微分截面以及角分布函数进行详细计算,分析电子屏蔽效应在不同入射电子能量和出射光子能量下的作用.结果表明,电子屏蔽效应会使轫致辐射单重和双重微分截面降低,在较低能电子入射时以及软光子区域抑制效果显著,而随着入射电子能量和出射光子能量的增加,电子屏蔽效应不断减弱.电子屏蔽效应对轫致辐射角分布的影响则较不明显. 展开更多
关键词 轫致辐射 碳原子及离子 微分截面 形状函数 电子屏蔽效应
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一种用于MCP的新型防离子反馈膜 被引量:1
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作者 张妮 孙超 +7 位作者 杨凯莉 朱宇峰 焦岗成 邱洪金 李朋博 郝子恒 黄武军 王江浩 《红外技术》 北大核心 2025年第1期115-120,共6页
传统技术制备的MCP防离子反馈膜在一定程度上会影响像管的信噪比,长时间的工作条件下也会降低像管的可靠性,基于传统防离子反馈膜缺陷导致的像管信噪比和可靠性性能亟需改善和提高的迫切需求,开展一种用于MCP的新型防离子反馈膜研究。... 传统技术制备的MCP防离子反馈膜在一定程度上会影响像管的信噪比,长时间的工作条件下也会降低像管的可靠性,基于传统防离子反馈膜缺陷导致的像管信噪比和可靠性性能亟需改善和提高的迫切需求,开展一种用于MCP的新型防离子反馈膜研究。采用原子层沉积技术(Atomic Layer Deposition,ALD)在有较高长径比的MCP通道内壁及输入端的通道孔处制备一层连续的高质量U型结构的防离子反馈膜,经MCP综合检测装置测试,与传统技术制备的MCP部件性能相比,新型防离子反馈膜致密,增益值较高,部件含碳量低,新型防离子反馈膜的MCP部件经制管后像管信噪比高,寿命可靠性高,此技术制备的新型防离子反馈MCP部件对与像增强器信噪比和可靠性性能的提升具有重要意义。 展开更多
关键词 新型防离子反馈膜 原子层沉积技术 高长径比 信噪比 长寿命
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