检索结果-南通市图书馆

Coexistence of Zero-Dimensional Electride State and Superconductivity in AlH_(2)Monolayer

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2023年第10期40卷 95-100页

作者：杨秋萍蒋雪赵纪军 key laboratory of materials modification by Laser Ion and Electron Beams(Ministry of Education)Dalian University of TechnologyDalian 116024China

Elect rides,which confine"excess anionic electrons"in subnanometer-sized cavities of a lattice,are exotic ionic *** propose a non-stoichiometric strategy to realize intrinsic two-dimensional(2D)superconducting elect ***_(2)monolayer,which is structurally identical to 1H-MoS_(2),possesses zero-dimensionally confined anionic electrons in the interstitial sites of A1 triangles,corresponding to a chemical formula of[AlH_(2)]^(+)e^(-).The interaction between interstitial anionic electrons(IAEs)and host cation lattice mainly accounts for stabilization of 1H-AlH_(2)***,1H-AlH_(2)monolayer is an intrinsic Bardeen-Cooper-Schrieffer superconductor with T_(c)=38 K,which is the direct consequence of strong coupling of the H-dominated high electronic states with Al acoustic branch vibrations and mid-frequency H-derived phonon softening modes caused by Kohn *** tensile strain,IAEs transform into itinerant electrons,favoring the formation of stable Cooper ***,T_(c)reaches up to 53 K at a biaxial fracture strain of 5%.Our findings provide valuable insights into the correlation between non-stoichiometric electrides and superconducting microscopic mechanisms at the 2D limit.

关键词： monolayer intrinsic superconductor

Optical Emission Spectroscopic Studies of ICP Ar Plasma

在线全文

学校读者我要写书评

暂无评论

Plasma Science and Technology 2007年第5期9卷 578-581页

作者：齐雪莲任春生张健马腾才 State key laboratory of materials modification by Laser Ion and Electron BeamsDalian University of TechnologyDalian 116024China

The ion line of 434.8 nm and atom line of 419.8 nm of Ar plasma produced by an inductively coupled plasma （ICP） were measured by optical emission spectroscopy and the influences from the working gas pressure, radio-frequency （RF） power and different positions in the discharge chamber on the line intensities were investigated in this study. It was found that the intensity of Ar atom line increased firstly and then saturated with the increase of the pressure. The line intensity of Ar^＋, on the other hand, reached a maximum value and then decreased along with the pressure. The intensity of the line in an RF discharge also demonstrated a jumping mode and a hysteresis phenomenon with the RF power. When the RF power increased to 400 W, the discharge jumped from the E-mode to the H-mode where the line intensity of Ar atom demonstrated a sudden increase, while the intensity of Ar^＋ ion only changed slightly. If the RF power decreased from a high value, e.g., 1000 W, the discharge would jump from the H-mode back to the E-mode at a power of 300 W. At this time the intensities of Ar and Ar^＋ lines would also decrease sharply. It was also noticed in this paper that the intensity of the ion line depended on the detective location in the chamber, namely at the bottom of the chamber the line was more intense than that in the middle of the chamber, but less intense than at the top, which is considered to be related to the capacitance coupling ability of the ICP plasma in different discharge areas.

关键词： optical emission spectroscopy inductively coupled plasma spectral line intensity Ar

Grafting Silane onto Silicate Glass Surface Treated by DBD in Air

在线全文

学校读者我要写书评

暂无评论

Plasma Science and Technology 2008年第5期10卷 556-559页

作者：任春生王德真王友年 State key laboratory for materials modification by Electron Ion and Laser BeamsDalian University of TechnologyDalian 116023China

Dielectric barrier discharge plasma in air was used to modify glass surface to induce the graft of silane onto the treated surface to increase the possibility of biomolecule immobilization. The plasma treated glass had been characterized by scanning electron microscopy （SEM）, Fourier transform infrared attenuated total reflection spectroscopy, X-ray photoelectron spectroscopy （XPS） and surface water contact angle measurement. The validity of grafting silane onto glass surface was approved by the analysis of water contact angle measurement, SEM and XPS. The grafted silane content was measured by visible absorption spectroscopy using acid Orange-7. It is shown that the grafting density of silane for glass samples increases significantly after plasma treatment.

关键词： dielectric barrier discharge plasma biomolecule immobilization silane graft

Quantitative relationship between the maximum streamer length and discharge voltage of a pulsed positive streamer discharge in water

在线全文

学校读者我要写书评

暂无评论

Plasma Science and Technology 2017年第8期19卷 76-79页

作者：温小琼李倩李井森任春生 key laboratory of materials modification by Laser Ion and Electron Beams (Ministry of Education)School of PhysicsDalian University of Technology

A linear relationship has been realized between the maximum streamer length and discharge voltage of a pulsed positive streamer discharge by measuring the streamer length in water with conductivity of 100 μS cm-1using high-speed photography. Based on Ohm＇s law, a quantitative equation has been derived for the dependence of the maximum streamer length on the discharge voltage of a pulsed positive streamer discharge in water. According to the equation, our results suggest that the streamers spontaneously stop propagating through water due to the voltage at the streamer head dropping below the ignition voltage of a pulsed positive streamer discharge.

关键词： length pulsed ignition spontaneously photography camera propagating realized correspondence captured

Three-Dimensional Dust Crystal

在线全文

学校读者我要写书评

暂无评论

Plasma Science and Technology 2006年第2期8卷 176-180页

作者：张宇刘金远刘悦王晓钢 State key laboratory of materials modification by Laser Ion and Electron Beams Dalian University of Technology Dalian 116024 China

Dust plasmas have received considerable attention in recent years due to the fact that a kind of crystal could be established, which is a typical example of an ideal material. In this system, the dust particles are often confined upon a three-dimensional sheath of an axissymmetric concave electrode, where the axial electrostatic force balances the gravitation and the radial electrostatic force keeps the dust from running away horizontally. In this paper, a threedimensional sheath structure is simulated through a liquid model, and the movement of the dust particles is simulated via the dynamic method. The crystals are obtained self consistently. The effect of both the electrode size and the mass of dust particles on the crystals are discussed. The simulation result demonstrates that two kinds of dust crystals could be established by varying the sheath diameter, and some proper conditions are necessary for the formation of a double layer dust crystal.

关键词： dust crystal three-dimensional

Mathematical model of electromagnetic elimination in tubule with high frequency magnetic field

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2006年第B01期16卷 47-51页

作者：郭庆涛金俊泽李廷举王同敏张琦曹志强 State key laboratory of materials modification by Laser Ion and Electron BeamsSchool of Materials Science and EngineeringDalian University of TechnologyDalian 116024China State key laboratory of materials modification by Laser Ion and Electron BeamsSchool of Materials Science and EngineeringDalia n University of TechnologyDalian 116024China

In order to find the ways to improve the elimination efficiency with high frequency magnetic field, a mathematical model of electromagnetic elimination (EME) in the tubule with high frequency magnetic field was set up. The calculated results show that by ignoring the flow of molten metal, when the surface magnetic induction intensity of the metal (B0) is 0.03 T and the diameter of the tubule is 8 mm, the non-metallic inclusions with 30 μm diameter can be wiped off in 7 s from the center of the molten aluminum, whereas the elimination time of the 5 μm non-metallic inclusions is more than 240 s. When B0 is 0.03 T, the diameter of the tubule is 8 mm and elimination time is more than 30 s, the elimination efficiency of 5μm, 10 μm and 30 μm non-metallic inclusions is about 60%, 90% and 100%, respectively, the elimination efficiency increases with the decreasing diameter of the tubule. It can be concluded that increasing the magnetic induction intensity or decreasing the diameter of the tubule can decrease the elimination time and improve the elimination efficiency in EME with high frequency magnetic field.

关键词：电磁消除管道消磁高频磁场数学模型非金属包含体

Low-dimensional non-metal catalysts:principles for regulating p-orbital-dominated reactivity

在线全文

学校读者我要写书评

暂无评论

npj Computational materials 2021年第1期7卷 1699-1732页

作者： Si Zhou Wei Pei Yanyan Zhao Xiaowei Yang Nanshu Liu Jijun Zhao key laboratory of materials modification by Laser Ion and Electron Beams(Dalian University of Technology)Ministry of EducationDalian 116024China

Activation of p-block elements to replace the rare and precious transition metals for renewable energy applications is highly *** this review,we go over recent experimental and theoretical progress on the low-dimensional non-metal materials for clean energy production,including carbon,silicon,oxide,boron,and phosphorus-based nanostructures,with the p-block elements serving as active *** aim to elucidate the mechanism for triggering activity in different kinds of non-metal systems,and extract general principles for controlling the p-orbital-mediated reactivity from a theoretical point of *** perspectives and challenges for developing high-efficiency non-metal catalysts are provided in the end.

关键词： reactivity orbital principles

The Electrostatic Cylindrical Sheath in a Plasma

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Plasma Science and Technology 2004年第2期6卷 2247-2249页

作者：王春华孙晓霞白冬雪 State key laboratory of materials modification by Laser Electron and Ion Beams Dalian University of Technology Dalian 116024 China

The electrostatic sheath with a cylindrical geometry in an ion-electron plasma is investigated. Assuming a Boltzmann response to electrons and cold ions with bulk flow, it is shown that the radius of the cylindrical geometry do not affect the sheath potential significantly. We also found that the sheath potential profile is steeper in the cylindrical sheath compared to the slab sheath. The distinct feature of the cylindrical sheath is that the ion density distribution is not monotonous. The sheath region can be divided into three regions, two ascendant regions and one descendant region.

关键词： plasma sheath ion-electron plasma

Kinetic Study on Channelling of Protons in Metallic Carbon Nanotubes

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2008年第7期25卷 2588-2591页

作者：赵丹宋远红王友年 State key laboratory of materials modification by beams School of Physics and Optoelectronic Technology Dalian University of Technology Dalian 116024

Based on the kinetic model and the dielectric response theory, a theoretical model is put forward to describe the transport of protons along nanotube axes. With the introduction of electron band structure for different nanotubes like zigzag and armchair nanotubes of metallic properties, the collective excitation of electrons on the cylinders induced by the incident ions is studied, showing several distinct peaks in the curves of the energy loss function. Furthermore, the stopping power and the self-energy are calculated as functions of ion velocities, especially taking into account the influence of damping coefficients. It is conceivable from the results that, in the kinetic formulation, plasmon excitation plays a major role in the stopping. And as the damping increases, the peaks of the stopping power shift to the lower velocities, with the broadening of the plasmon resonance.

关键词： the power-law exponents precipitation durative abrupt precipitation change