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Study on the energy level limitations of triplet-triplet annihilation upconversion with anthracene-isomerized dimers as annihilators
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作者 Shanshan Liu Tingting Gou +4 位作者 Xiaojuan Song Riming Hu Heyuan Liu Xiyou Li Xuchuan Jiang 《ChemPhysMater》 2024年第2期187-193,共7页
The enhancement in the efficiency of triplet-triplet annihilation upconversion(TTA-UC)is mainly determined by the triplet energy transfer(TET)and triplet-triplet annihilation(TTA)between the sensitizers and annihilato... The enhancement in the efficiency of triplet-triplet annihilation upconversion(TTA-UC)is mainly determined by the triplet energy transfer(TET)and triplet-triplet annihilation(TTA)between the sensitizers and annihilators.The TET process works efficiently by adjusting the concentration ratio of the sensitizers and annihilators.The efficiency of TTA is determined by the properties of the annihilator.Because TTA is a Dexter-type energy transfer and is affected by the diffusion rate,the energy levels of the excited states and the molecular size are both crucial in TTA.In this study,four isomerized dimers of 9,10-diphenlanthracene(DPA)and anthracene(An)were designed and prepared as annihilators for TTA-UC.The singlet and triplet energy levels could be adjusted by altering the connection position while maintaining the molecular weight and size.When PtOEP was used as the sensitizer,the maximum upconversion efficiency of 9-[4-(9-anthracenyl)phenyl]-10-phenylanthracene(9DPA-9An)was~11.18%.This is four times higher than that of 9,10-diphenyl-2,9-bianthracene(2DPA-9An,2.63%).The calculation of the energies of T_(1)and the higher triplet state(T_(3),because E(T_(2))is similar to the E(T)of these dimers)for these dimers has provided insights into the underlying reasons.These indicated that the energy gap value of 2×E(T_(1))-E(T_(3))is the determining factor for TTA efficiency.This work may provide a better understanding of the excited-state energy levels,which is crucial for designing novel annihilators to enhance the TTA-UCefficiency. 展开更多
关键词 UPCONVERSION annihilATOR Triplet-triplet annihilation energy levels
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Cold Fusion Based on Matter-Antimatter Plasma Formed in Molecular Crystals 被引量:1
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作者 Mohamed Assaad Abdel-Raouf Abdelfattah T. Elgendy Amr Abd Al-Rahman Youssef 《Journal of High Energy Physics, Gravitation and Cosmology》 2022年第1期56-66,共11页
The main purpose of this work is to shed light on the possibility of producing huge amount of energy based on the construction matter-antimatter plasma in a molecular crystal. It is assumed that two beams of isotherma... The main purpose of this work is to shed light on the possibility of producing huge amount of energy based on the construction matter-antimatter plasma in a molecular crystal. It is assumed that two beams of isothermal hydrogen and antihydrogen are injected into a palladium crystal leading to a plasma state composed of particles and antiparticles. The collapse of this state releases a huge amount of energy which can be used as fuel for space shuttles. Thus, the novel system of isothermal pressure interaction enhances the energy power carried out by the quantum ion acoustic soliton (QIAS). In addition to the energy power released from the particle-antiparticle annihilation. The probability of merging the energy from these two cases is available at certain condition. The released energy may be a significant step in solving the energy scape of Tokomak to produce fusion energy. The study starting from the one-dimensional quantum hydrodynamic model (in which the term of electron-positron and proton-antiproton for hydrogen-antihydrogen is included), a Korteweg de Vries equation (kdv) is derived, the QIAS energy experiences and the annihilation energy power are calculated. It is found that the total energy of QIAS and the energy resulting from hydrogen-antihydrogen annihilation are important step towards the establishment of a cold fusion power station. 展开更多
关键词 Cold Fusion annihilation energy Plasma energy Ion-Acoustic Plasma Cold and Hot Plasma matter-antimatter Plasma in Molecular Crystals Fuel for Space Shuttles in Palladium Crystals
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STUDY OF RECOVERY IN DEFORMED Ni-Cr-Co SUPERALLOYS USING POSITRON ANNIHILATION
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作者 DENG Wen XIONG Liangyue LONG Qiwei Institute of Metal Research International Centre for Materials Physics,Academia Sinica,Shenyang,China Associate Professor,Institute of Metal Research,Academia Sinica,Shenyang 110015,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1992年第9期214-218,共5页
The recovery recrystallization of 3 deformed Ni-Cr-Co superalloys with different Co con- tents has been studied using positron annihilation technique and TEM.The alloys with low Co content have more defects occurred t... The recovery recrystallization of 3 deformed Ni-Cr-Co superalloys with different Co con- tents has been studied using positron annihilation technique and TEM.The alloys with low Co content have more defects occurred than ones with high Co content,and the former may be faster in dislocation recovery than the latter.Thus,the apparent activation energy of recrystallization increases with the increase of their Co content in alloys.The relationship be- tween apparent activation energy and stacking fault energy together with their effect on re- covery were also discussed. 展开更多
关键词 positron annihilation stacking fault apparent activation energy recrystallization RECOVERY
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The Electromagnetic Nature of Gravitation and Matter-Antimatter Antigravity. Surmise on Quantum Vacuum Gravitation and Cosmology
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作者 Constantin Meis 《Journal of Modern Physics》 2022年第6期949-968,共20页
We show that the electromagnetic quantum vacuum derives directly from Maxwell’s theory and plays a primary role in quantum electrodynamics, particle physics, gravitation and cosmology. It corresponds to the electroma... We show that the electromagnetic quantum vacuum derives directly from Maxwell’s theory and plays a primary role in quantum electrodynamics, particle physics, gravitation and cosmology. It corresponds to the electromagnetic field ground state at zero frequency, a zero-energy cosmic field permeating all of space and it is composed of real states, called kenons (κενο = vacuum). Photons are local oscillations of kenons guided by a non-local vector potential wave function with quantized amplitude. They propagate at the speed imposed by the vacuum electric permittivity ε<sub>0</sub> and magnetic permeability μ<sub>0</sub>, which are intrinsic properties of the electromagnetic quantum vacuum. The electron-positron elementary charge derives naturally from the electromagnetic quantum vacuum and is related to the photon vector potential. We establish the masse-charge equivalence relation showing that the masses of all particles (leptons, mesons, baryons) and antiparticles are states of the elementary charges and their magnetic moments. The equivalence between Newton’s gravitational law and Coulomb’s electrostatic law results naturally. In addition, we show that the gravitational constant G is expressed explicitly through the electromagnetic quantum vacuum constants putting in evidence the electromagnetic nature of gravity. We draw that G is the same for matter and antimatter but gravitational forces should be repulsive between particles and antiparticles because their masses bear naturally opposite signs. The electromagnetic quantum vacuum appears to be the natural link between quantum electrodynamics, particle physics, gravitation and cosmology and constitutes a basic step towards a unified field theory. Dark Energy and Dark Matter might originate from the electromagnetic quantum vacuum fluctuations. The calculated electromagnetic vacuum energy density, related to the cosmological constant considered responsible for the cosmic acceleration, is in good agreement with the astrophysical observations. The cosmic acceleration may be due to both “quantum vacuum fluctuations” and “matter-antimatter gravitational repelling”. All the above results are established without stating any assumptions or postulates. Next, we advance two hypotheses with cosmological impact. The first is based on the possibility that gravitation is due to the electromagnetic quantum vacuum density of states fluctuations giving rise to a photon pressure at the characteristic collective oscillation frequencies of the charge densities composing the bodies (Electromagnetic Push Gravity). The second advances that energy, matter and antimatter in the universe emerge spontaneously from the quantum vacuum fluctuations as residues that remain stable in space and we present the main principles upon which a new cosmological model may be developed overcoming the well-known Big Bang issues. 展开更多
关键词 Photons Electromagnetic Waves Electromagnetic Quantum Vacuum Dark Light Kenons GRAVITATION matter-antimatter Antigravity Electromagnetic Push Gravity Dark energy Cosmological Constant Dark Matter Elementary Charges Mass-Charge Relation Cosmology Unified Field Theory
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Origin of the Universe, Dark Energy, and Dark Matter 被引量:1
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作者 T. R. Mongan 《Journal of Modern Physics》 2018年第5期832-850,共19页
This explanation of the origin of the universe, dark energy, and dark matter is based on quantum mechanics, general relativity, thermodynamics, and Shannon information theory. It envisions our universe beginning with ... This explanation of the origin of the universe, dark energy, and dark matter is based on quantum mechanics, general relativity, thermodynamics, and Shannon information theory. It envisions our universe beginning with a quantum fluctuation from nothing into an unstable closed space with our familiar three space dimensions accompanied by seven extra space dimensions, the four basic forces unified, and initial radius of the order of the proton wavelength. The compact extra dimensions collapsed to their ground state with radius of the order of today’s Planck length, injecting most of the entropy (information) in the extra dimensions into our three space dimensions and inflating them by a factor of about e58&asymp;1025. The constant ground state energy of the compact extra dimensions is related to the dark energy (vacuum energy) driving today’s accelerating expansion of our three-dimensional universe. With the usual values of G, , c, and Hubble constant? h0=0.65, the dark energy fraction is &asymp;0.7. Immediately after inflation, the strong force acting only on matter was an effective “strong gravity” (about 1038 times stronger than gravity today) causing 83% of matter to coalesce into small impenetrable closed systems interacting only by gravity and constituting most of the dark matter. Other universes may have formed similarly in the infinite sweep of cosmic time, but are of no practical significance because they are profoundly elsewhere. The holographic principle (a consequence of quantum mechanics, general relativity, thermodynamics, and Shannon information theory) indicates only a finite number (about 10122) of bits of information encoded on the event horizon will ever be available to describe all physics within our universe. There are no sources or sinks of information outside the universe, so the universe must be described as a closed system. Matter dominance over anti-matter relates to the finite number of bits of information in the universe, as does the fact that theories involving continuum mathematics only approximate an underlying theory involving discrete mathematics. Ordinary matter constitutes only about 5% of the energy density of the universe. Holographic analysis of large scale structures composed of stars accounts for: minimum stellar mass as a function of time;the hierarchy of star clusters, galaxies, and galaxy clusters;and supermassive black holes. It identifies configurations of spiral and elliptical galaxies consistent with conservation of mass and angular momentum accounting for the 15% of bulgeless disks found in the survey of 15,000 spiral galaxies in the sixth SDSS data release. The smallest scale structures are usually described by the Standard Model of elementary particles, based on local quantum field theory. The Standard Model cannot be the final theory of elementary particles because: it incorrectly assumes neutrinos are massless;it cannot account for the bizarre mass spectrum of three generations of four Standard Model fermions;and does not provide the necessary non-local discrete theory of elementary particles. A holographic (and therefore non-local) preon theory involving strands with finite energy density instead of point particles can be outlined, but calculation in such a framework is difficult and gives no insight into the fermion mass spectrum. 展开更多
关键词 Quantum COSMOLOGY DARK energy DARK MATTER matter-antimatter Asymmetry
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Accelerated Expansion of Space, Dark Matter, Dark Energy and Big Bang Processes
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作者 Auguste Meessen 《Journal of Modern Physics》 2017年第2期251-267,共17页
The accelerated expansion of our universe results from properties of dark matter particles deduced from Space-Time Quantization. This theory accounts for all possible elementary particles by considering a quantum of l... The accelerated expansion of our universe results from properties of dark matter particles deduced from Space-Time Quantization. This theory accounts for all possible elementary particles by considering a quantum of length a in addition to c and h. It appears that dark matter particles allow for fusion and fission processes. The resulting equilibrium enables the cosmic dark matter gas to produce dark energy in an adaptive way. It keeps the combined matter-energy density at a constant level, even when space is expanding. This accounts for the cosmological constant &Lambda;and the accelerated expansion of space without requiring any negative pressure. The Big Bang is related to G, c, h and a. It started with a “primeval photon” and led to the cosmic matter-antimatter asymmetry as well as inflation. 展开更多
关键词 Accelerated Expansion DARK MATTER DARK energy SPACE-TIME Quantization Big Bang INFLATION matter-antimatter Asymmetry
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以BAlq为主体的高效高色纯度的红色有机电致磷光器件 被引量:10
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作者 申霖 徐昊 +3 位作者 叶丹琴 吴晓明 华玉林 印寿根 《发光学报》 EI CAS CSCD 北大核心 2008年第1期51-55,共5页
以铱配合物红色磷光体Ir(piq)2(acac)为掺杂剂,制备了基于BAlq材料的红色电致磷光器件,其结构为ITO/NPB(30nm)/Ir(piq)2(acac)∶BAlq(25nm)/BCP(13nm)/Alq3(35nm)/LiF(1nm)/Al(1000nm),当掺杂浓度为8%的时候,器件发光的色坐标为(x=0.67,... 以铱配合物红色磷光体Ir(piq)2(acac)为掺杂剂,制备了基于BAlq材料的红色电致磷光器件,其结构为ITO/NPB(30nm)/Ir(piq)2(acac)∶BAlq(25nm)/BCP(13nm)/Alq3(35nm)/LiF(1nm)/Al(1000nm),当掺杂浓度为8%的时候,器件发光的色坐标为(x=0.67,y=0.32),基本满足了全色显示对红色发光的要求。在电压为16V时,器件达到最高亮度9380cd/m2。在电流密度为5.45mA/cm2时,外量子效率达到最大5.7%。由于磷光体Ir(piq)2(acac)的磷光寿命较短,所以器件在高电流密度下,仍然保持较高的外量子效率。电流密度为100mA/cm2时,外量子效率仍然维持在4.7%。进一步研究表明在器件中短程的Dexter能量传递以及红光染料对空穴的直接捕获两种机制同时存在。 展开更多
关键词 磷光体 二线态 能量传递 T—T湮灭
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卟啉钯敏化剂构效性质与三线态-三线态湮灭上转换性能研究 被引量:2
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作者 叶常青 于雪 +3 位作者 陈硕然 梁作芹 周宇扬 王筱梅 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2021年第1期71-79,共9页
上转换发光是一种将长波长的激发光转化为短波长发射的反斯托克斯发光现象,三线态-三线态湮灭上转换(TTA-UC)能够在较低密度能量下被激发,且上转换量子产率高,因此获得研究者们广泛关注。关于敏化剂分子结构与上转换发光性能相关性的研... 上转换发光是一种将长波长的激发光转化为短波长发射的反斯托克斯发光现象,三线态-三线态湮灭上转换(TTA-UC)能够在较低密度能量下被激发,且上转换量子产率高,因此获得研究者们广泛关注。关于敏化剂分子结构与上转换发光性能相关性的研究一直是TTA-UC研究领域的重要热点,选择两种代表性的卟啉钯光敏剂[PdOEP-八乙基卟啉钯(Ⅱ)和PdBrTPP-四溴苯基卟啉钯(Ⅱ)]与蒽衍生物9,10-(4-羟甲基)苯基蒽p-DHMPA发光剂组合上转换体系作为研究模型,通过一系列合成工作获得材料分子后,进一步比较两种敏化剂的光谱性质与体系最终上转换性能之间关系。通过细致研究敏化剂和发光剂的荧光发射和寿命等光谱性质对敏化剂系间窜越,三线态-三线态能量转移及三线态-三线态湮灭等能量传递过程的影响后,发现在532 nm处的摩尔吸光系数PdBrTPP(10.8 cm^-1·mmol^-1)大于PdOEP(3.0 cm^-1·mmol^-1);三线态寿命PdBrTPP(173.13μs)大于PdOEP(109.21μs)。但与p-DHMPA配对时光敏剂与发光剂的三线态能级差ΔE TT,PdOEP(0.140 eV)却高于PdBrTPP(0.062 eV),通过Stern-Volmer方程得到Stern-Volmer猝灭常数K SV和双分子猝灭常数k q值也是PdOEP略高,最终表现出上转换阈值PdOEP/p-DHMPA(22.40 mW·cm^-2)小于PdBrTPP/p-DHMPA(29.78 mW·cm^-2),上转换发光效率ΦUC,PdOEP/p-DHMPA(28.3%)大于PdBrTPP/p-DHMPA(26.8%)。因此,卟啉钯敏化剂的构效对三重态湮灭上转换发光效率影响最为重要的决定因素是敏化剂三线态高低。对于不同的敏化剂,在分子主体结构、摩尔吸光系数与三线态寿命等光谱参数差别不大的情况下,敏化剂的三线态能级越高,就将会具有更大的上转换发光效率。然而如果以总上转换能力指标来评价,PdBrTPP的共轭结构能够提升其在激发波长处吸收更多光子的能力,具有比PdOEP更高的摩尔吸光系数,造成其总上转换能力η比PdOEP高3.4倍。因此从上转换总效能指标来评价,通过敏化剂分子设计调控其在激发光波长处的摩尔吸光系数也不失为一种简单易行的方法。 展开更多
关键词 三线态-三线态湮灭 上转换 敏化剂 构效关系 三线态能级 摩尔吸光系数
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LaCl_3:Ce^(3+)闪烁体正电子湮没寿命谱仪 被引量:2
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作者 高鑫 白雪宁 +1 位作者 陈宜保 何元金 《核电子学与探测技术》 CAS CSCD 北大核心 2007年第2期243-245,249,共4页
对国内最新研制出的LaCl3:Ce3+闪烁晶体时间特性进行了测试,用该种晶体尝试组建了正电子湮没寿命谱仪,时间分辨率达到了350ps。由于LaCl3:Ce3+探头在具有快速时间响应特性的同时还具有较高的能量分辨率,用该探头组建正电子湮没寿命谱仪... 对国内最新研制出的LaCl3:Ce3+闪烁晶体时间特性进行了测试,用该种晶体尝试组建了正电子湮没寿命谱仪,时间分辨率达到了350ps。由于LaCl3:Ce3+探头在具有快速时间响应特性的同时还具有较高的能量分辨率,用该探头组建正电子湮没寿命谱仪将具有许多潜在的优势。 展开更多
关键词 LaCl3:Ce^3+闪烁体 正电子湮没寿命谱仪 能量分辨率 时间分辨率
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TATB基PBX纳米孔隙的正电子湮没寿命谱 被引量:1
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作者 杨仍才 田勇 +1 位作者 张伟斌 杜宇 《含能材料》 EI CAS CSCD 北大核心 2011年第2期200-203,共4页
为研究压制参数对TATB基高聚物粘结炸药(PB X)微观结构的影响,压制了密度为1.6~1.9 g·cm-3的PBX,采用了正电子湮没寿命谱(PALS)技术表征了其微观结构,讨论了不同压制密度PBX的纳米孔隙的变化。结果显示:压制密度越大,PBX中纳... 为研究压制参数对TATB基高聚物粘结炸药(PB X)微观结构的影响,压制了密度为1.6~1.9 g·cm-3的PBX,采用了正电子湮没寿命谱(PALS)技术表征了其微观结构,讨论了不同压制密度PBX的纳米孔隙的变化。结果显示:压制密度越大,PBX中纳米孔隙浓度越小,平均尺寸越大,这表明压制过程中,PBX界面孔隙不断减小,TATB晶体内部孔隙却不断增大。 展开更多
关键词 高能物理学 TATB基PBX 压制 纳米孔隙 正电子湮没寿命谱
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正电子能量转换研究进展 被引量:4
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作者 王少阶 《原子核物理评论》 CAS CSCD 北大核心 2004年第4期284-285,305,共3页
简要介绍了正电子能量转换的原理、优点、重要应用前景及主要研究领域.
关键词 正电子 能量转换 研究进展 优点
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低能V^(+)注入花生种子引起生物体的微结构变化及其机理 被引量:2
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作者 陆挺 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 2000年第6期788-790,共3页
以植物干种子花生为生物体材料 ,注入 2 0 0keV的低能V+离子 .采用正电子湮没技术(PAT)测定了经离子注入和未经离子注入的 2类花生生物样品的正电子湮没寿命谱 (PAL) .实验结果表明 ,在花生种子生物体内存在着大量微小的孔洞 ,孔洞的直... 以植物干种子花生为生物体材料 ,注入 2 0 0keV的低能V+离子 .采用正电子湮没技术(PAT)测定了经离子注入和未经离子注入的 2类花生生物样品的正电子湮没寿命谱 (PAL) .实验结果表明 ,在花生种子生物体内存在着大量微小的孔洞 ,孔洞的直径为 0 .7nm .经低能离子注入以后 ,这些孔洞的大小会有所变化 . 展开更多
关键词 低能离子注入 生物效应 正电子湮没
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正负电子三光子湮灭中光子能谱的Monte Carlo计算 被引量:1
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作者 程锦荣 许强 《计算物理》 CSCD 北大核心 1991年第1期30-36,共7页
用Monte Carlo方法计算正负电子三光子湮灭的光子能谱,并与量子电动力学(QED)理论谱及实验结果进行了比较,三种结果符合甚好。
关键词 电子 三光子湮灭 光子能谱
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类金刚石薄膜的慢正电子分析
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作者 程宇航 吴一平 +4 位作者 邹柳娟 陈建国 乔学亮 谢长生 翁惠民 《无机材料学报》 SCIE EI CAS CSCD 北大核心 1998年第2期214-218,共5页
采用射频-直流等离子化学气相沉积法制备类金刚石薄膜,用慢正电子湮灭技术研究了类金刚石薄膜中缺陷的深度分布,并系统研究了工艺参数对类金刚石薄膜中缺陷浓度的影响.实验结果表明,单晶Si衬底具有很高的缺陷浓度,类金刚石薄膜中... 采用射频-直流等离子化学气相沉积法制备类金刚石薄膜,用慢正电子湮灭技术研究了类金刚石薄膜中缺陷的深度分布,并系统研究了工艺参数对类金刚石薄膜中缺陷浓度的影响.实验结果表明,单晶Si衬底具有很高的缺陷浓度,类金刚石薄膜中的缺陷浓度较低.且缺陷均匀分布,薄膜表面存在一缺陷浓度较高的薄层,而膜一基之间存在一很宽的界面层,界面层内缺陷浓度随离衬底表面距离的增加而线性降低,到达薄膜心部后,缺陷浓度趋于稳定.类金刚石薄膜的缺陷浓度和膜-基界面层宽度都随负偏压的升高呈先降低、后增加再降低的变化趋势.薄膜中的缺陷浓度随混合气体中C2H2含量的升高而单调增大,但C2H2含量对界面层宽度没有影响. 展开更多
关键词 类金刚石薄膜 缺陷 慢正电子束 薄膜
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a-C:H(N)薄膜的慢正电子分析
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作者 程宇航 吴一平 +4 位作者 邹柳娟 陈建国 乔学亮 谢长生 翁惠民 《功能材料》 EI CAS CSCD 北大核心 1999年第1期54-56,共3页
采用C2H2和N2的混合气体在单晶Si衬底上用射频一直流等离子化学气相沉积法制备a-C:H(N)薄膜,用Fourier红外谱研究了a-C:H(N)薄膜的结构。用慢正电子湮没技术研究了类金刚石薄膜中缺陷的深度分布以及N的百分含量对薄膜中缺陷浓... 采用C2H2和N2的混合气体在单晶Si衬底上用射频一直流等离子化学气相沉积法制备a-C:H(N)薄膜,用Fourier红外谱研究了a-C:H(N)薄膜的结构。用慢正电子湮没技术研究了类金刚石薄膜中缺陷的深度分布以及N的百分含量对薄膜中缺陷浓度和缺陷类型的影响。Fourier红外测试结果表明,a-C:H(N)薄膜中氮含量随混合气体中N2百分含量的升高而增大,薄膜中碳氮原子形成C≡N键。慢正电子分析表明.单晶Si衬底具有很高的缺陷浓度,类金刚石薄膜中的缺陷浓度较低,且缺陷均匀分布,薄膜表面存在一缺陷浓度较高的薄层,而膜一基之间存在一很宽的界面层。a-C:H(N)薄膜的缺陷浓度随N含量的增加而增大,但含饲量不改变薄膜中的缺陷类型。 展开更多
关键词 a-C:H(N)薄膜 缺陷 慢正电子束 正电子湮没
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Ni-Cr-Co高温合金回复行为的正电子湮没研究
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作者 邓文 熊良钺 龙期威 《金属学报》 SCIE EI CAS CSCD 北大核心 1991年第6期B433-B437,共5页
用正电子湮没技术及透射电镜研究了三种不同Co含量的 Ni-Cr-Co高温合金经室温形变后的回复再结晶过程.结果表明,在相同的形变量下,Co含量低的合金比 Co含量高的合金产生的缺陷多;在回复过程中,Co含量低的合金其位错回复比Co含量高的合金... 用正电子湮没技术及透射电镜研究了三种不同Co含量的 Ni-Cr-Co高温合金经室温形变后的回复再结晶过程.结果表明,在相同的形变量下,Co含量低的合金比 Co含量高的合金产生的缺陷多;在回复过程中,Co含量低的合金其位错回复比Co含量高的合金快,而且合金的表观再结晶激活能随Co含量的增加而增加.讨论了Co含量,表观再结晶激活能和层错能之间的关系以及它们对回复过程的影响。 展开更多
关键词 镍基合金 高温 正电子湮没 层错能
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正电子湮没诱发俄歇电子能谱装置的物理设计
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作者 秦秀波 王平 +3 位作者 姜小盼 于润升 王宝义 魏龙 《核技术》 CAS CSCD 北大核心 2009年第4期264-268,共5页
与X射线、高能电子或中子激发俄歇电子能谱相比,正电子湮没诱发俄歇电子能谱(PAES)具有极表面选择性、高信噪比、低辐照损伤等特点。本文介绍北京慢正电子强束流的PAES装置,采用4×10-3T磁场对正电子和俄歇电子进行输运,强弱磁场梯... 与X射线、高能电子或中子激发俄歇电子能谱相比,正电子湮没诱发俄歇电子能谱(PAES)具有极表面选择性、高信噪比、低辐照损伤等特点。本文介绍北京慢正电子强束流的PAES装置,采用4×10-3T磁场对正电子和俄歇电子进行输运,强弱磁场梯度对俄歇电子进行平行化,法拉第筒对俄歇电子的能量进行调制,使得整个系统的能量分辨优于2eV。 展开更多
关键词 俄歇电子能谱 正电子湮没 飞行时间 能量分辨 法拉第筒
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正电子湮没辐射多普勒展宽谱的处理及其应用
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作者 郑万辉 彭郁卿 +1 位作者 张怡萍 王景成 《核技术》 CAS CSCD 北大核心 1991年第4期200-206,共7页
用迭代法对湮没辐射的Doppler展宽谱去卷职,获取湮没辐射的本征分布。用高斯—牛顿法将本征分布拟合为一个高斯函数(心电子贡献)和抛物线函数(传导电子贡献)之和。从本征分布和抛物线函致可以算出电子的动量分布信息和估测费米能。用纯G... 用迭代法对湮没辐射的Doppler展宽谱去卷职,获取湮没辐射的本征分布。用高斯—牛顿法将本征分布拟合为一个高斯函数(心电子贡献)和抛物线函数(传导电子贡献)之和。从本征分布和抛物线函致可以算出电子的动量分布信息和估测费米能。用纯Ge探测器测量了Al、Ag、Cu、Co、Ni、Sa、In、Mo、W、Zr,Ti、Ge、Si等13种材料的多普勒展宽谱,算出它们的动量分布和费米能,显示各种材料的动量分布明显不同,由实验测得的费米能值与由自由电子气模型计算的理论值很好符合。对Fe Si B非晶和晶态合金的研究表明:两者的动量分布差异甚小,但费米能略有不同。 展开更多
关键词 正电子湮没 多普勒展宽谱 费米能
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均匀磁场中带电粒子运动的代数解法
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作者 刘建军 齐向红 裴晓林 《河北师范大学学报(自然科学版)》 CAS 1995年第4期52-55,共4页
把均匀磁场中带电粒子的哈密顿用产生、湮灭算符表示出来,并利用产生、湮灭算符的性质得到了朗道能级及相应的波函数。
关键词 均匀磁场 带电粒子 量子力学 代数解法
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用正电子湮没方法研究氦离子等离子体辅助分子束外延InP( InGaAsP)/InP结构
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作者 白人骥 赵杰 《核技术》 CAS CSCD 北大核心 2001年第2期102-106,共5页
用氦离子等离子体辅助分子束外延(PAMBE)方法生长了InP(InGaAsP)/InP结构。研究 结果发现,PAMBE外延层具有很高的电阻率和很快的光反应特性。用慢正电子湮没方法研究了 这一外延层,测量结果说明这些特性... 用氦离子等离子体辅助分子束外延(PAMBE)方法生长了InP(InGaAsP)/InP结构。研究 结果发现,PAMBE外延层具有很高的电阻率和很快的光反应特性。用慢正电子湮没方法研究了 这一外延层,测量结果说明这些特性与等离子体造成的缺陷及缺陷随温度变化有直接关系。 展开更多
关键词 慢正电子湮没 氦离子等离子体 分子束外延 磷化铟半导体 掺杂 缺陷
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