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1.
本文综述了我国核农学的研究领域及国际上的研究现况,并介绍了我们在这一领域内取得的成果和发展前景。The research status of nuclear agronomy in our country and its development in othercountries are summaried in this paper. The results obtained in nuclear agronomy and its prospect arealso introduced.  相似文献   

2.
简要介绍了 SHIM物理及其近 1 0年来国际研究的最新进展 ,重点介绍了中国科学院近代物理研究所在该学科研究中所获得的部分最新研究结果 ,展望了 SHIM物理的发展趋势.Swift Heavy Ion in Matter(SHIM) physics and its new progresses of research in the world in recent ten years were briefly introduced. The results obtained on SHIM physics including strong electronic excitation effect in solid materials and its applications, as well as highly charged state atomic physics, obtained by Institute of Modern Physics, the Chinese Academy of Sciences were mainly introduced. The tendency of the discipline in future was presented.  相似文献   

3.
金属材料中氦的扩散与氦泡的形核生长研究   总被引:4,自引:1,他引:3  
简述了金属材料中氦聚集行为的研究概况 ,特别是本课题组近年来对奥氏体不锈钢中氦扩散及氦泡形核生长机制的研究结果 ,并提出了这个领域有待解决的问题. Studies of diffusion and aggregation behaviour of helium in metallic materials are very important to solve the problem of helium embrittlement in structural materials used in the environment of nuclear power. Experimental studies on helium diffusion and aggregation in austenitic stainless steels in a wide temperature range have been performed in our research group and the main results obtained are briefly summarized. The mechanism of nucleation growth of helium bubbles has been...  相似文献   

4.
核子结构研究半世纪   总被引:1,自引:0,他引:1  
评述了近半个世纪来核子结构研究的主要进展,着重评述了近十年来用极化轻子深度非弹散射研究核子自旋、磁矩结构的进展.也还评述了当前核子结构研究中的重要问题. The essential developments of the nucleon structure studies in the last half century are reviewed. The nucleon spin and magnetic moment structure studies with the polarized lepton nucleon deep inelastic scattering in the recent years are specially analyzed. The important topics in the contamporary studies of the nucleon structure is discussed.  相似文献   

5.
6.
评述和分析了磁约束核聚变理论研究、数值模拟和实验研究等方面最近几年共同关心的一个重要问题——寻找托卡马克等离子体湍流中的带状剪切流(zonal flows)。简要介绍了作者最近对电阻性-重力模湍流中的带状剪切流的研究结果。 Progress of the research on the zonal flows in tokamak plasma turbulence is surveyed, especially it is reviewed that the zonal flows observed in the experiments and numerical simulations on atmosphere turbulence and ocean turbulence and the discovery of H-mode in tokamak experiments how lead the researchers in magnetic confinement fusion community to find out the existence of the zonal flow in tokamak plasma turbulence and subsequently give the experimental verification of its existence. Finally, the results of our research on zonal flow generation and evolution in resistive-g mode turbulence are presented in brief.  相似文献   

7.
重离子辐射植物的诱变效应研究及应用   总被引:5,自引:0,他引:5  
重离子生物技术已引起人们的广泛关注, 植物育种是重离子生物技术研究和应用的热点之一。 简要介绍了重离子的基本特征和在育种应用中的优势, 综述了重离子辐射对植物分子、 细胞、 个体3个水平的诱变效应研究及重离子辐射育种取得的进展。 Heavy ion biotechnology has received much attention since the mid 1980s, when the first mutagenic effect of heavy ion beams was found in rice. Since then, plant breeding is one of the focuses in heavy ion biotechnology. In this paper we outlined the recent developments in plant breeding by heavy ion beams. We introduced briefly the essential characteristics and superiority of heavy ion beams applied in plant breeding, and reviewed further the mutagenic research in three levels(e.g., molecular, cell and individual) of plants. At last, we summarized artificial mutants obtained in plants irradiated by heavy ion beams.  相似文献   

8.
本文概要介绍了近几年来国防上关于核少体问题研究方面的进展状况及新动向. The current status and progress are outlined in few-body nuclear physics research. Latest trends in this field are reviewed as well.  相似文献   

9.
评述了磁性多层膜中磁层、界面和非磁层的结构及磁性的穆斯堡尔谱研究的新进展,并展望了今后的研究方向.A new progress in Mssbauer study on the magnetic structure and magnetic properites of the magnetic layer, interface layer and nonmagnetic layer in the magnetic multilayers is reviewed.Further research trend is also discussed.  相似文献   

10.
简要介绍了当前强作用物理研究的基本目标 .对其中QCD的参数和强子谱研究的问题做了较细致的讨论 ,特别是讨论了北京正负电子对撞机 /北京谱仪可以开展的强子物理实验研究.The basic goals for the study of hadronic physics are briefly discussed. The determination of the QCD parameters and the study of the hadron spectroscopy are discussed in more detail. It is shown that BEPC/BES can play a role in the study of hadron physics.  相似文献   

11.
Results of radionuclide activity concentration measurements in deposition and ground-level air conducted at the station of the Institute of Physics situated 3.5 km from the Ignalina Nuclear Power Plant (Ignalina NPP) in 2005 are analyzed. Atmospheric depositional fluxes of 7Be, 60Co and 137Cs are estimated. Radionuclide particle deposition rates are calculated. The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model of the global dispersion and deposition is used to explain variations in the 137Cs activity concentration in the ground-level air in the Ignalina NPP region in 2005. An increase in the 137Cs activity concentration of up to 17.4 μBq m−3 on 30 October-5 November is studied. Modelling results show that the Chernobyl NPP Unit 4 Sarcophagus and the radiocaesium resuspension from the Chernobyl NPP accident polluted regions are sources of 137Cs to the environment of the Ignalina NPP. Results on solubility in water of aerosols — carriers of 137Cs — are discussed.  相似文献   

12.
This paper offers a review of the contributions of German research groups in the field of fibre-optical communications until now. Since the latest publications are also taken into account which in part are not yet printed, a survey is given at the same time of current activities in this field in Germany.  相似文献   

13.
The solutions of a renormalized BCS equation are studied in three space dimensions in s, p and d waves for finite-range separable potentials in the weak to medium coupling region. In the weak-coupling limit, the present BCS model yields a small coherence length and a large critical temperature, , appropriate for some high- materials. The BCS gap, , and specific heat as a function of zero-temperature condensation energy are found to exhibit potential-independent universal scalings. The entropy, specific heat, spin susceptibility and penetration depth as a function of temperature exhibit universal scaling below in p and d waves. Received: 18 July 1997 / Revised: 8 September 1997 / Accepted: 29 September 1997  相似文献   

14.
It is shown that bulk semiconductors exhibit strongly asymmetric Fano-type resonance profiles in magnetoabsorption processes involving the formation of hot electron-hole pairs (EHPs) and accompanied by the scattering of the EHPs by defects. This result is valid for transitions to electronic states with large Landau quantum numbers, when the Coulomb interaction plays a small role. The physical reason for such a sharp change in the magnetoabsorption coefficient as compared with the expected result for the ordinary density of states in a quantizing magnetic field is that the electronic excitations are quasi-one-dimensional. The form of the resonance absorption is in good qualitative agreement with the experimental data. Pis’ma Zh. éksp. Teor. Fiz. 63, No. 8, 619–622 (25 April 1996)  相似文献   

15.
We present the action and transformation laws of supergravity in 11 dimensions which is expected to be closely related to the O(8) theory in 4 dimensions after dimensional reduction.  相似文献   

16.
张金松  吴懿平  王永国  陶媛 《物理学报》2010,59(6):4395-4402
高工作电流在集成电路微互连结构中产生大量焦耳热,引起局部区域的温升、形成高温度梯度,金属原子沿着温度梯度反向运动发生热迁移.热迁移是集成电路微互连失效的主要原因之一.阐述了热迁移原理、失效模式及原子迁移方程.综述和分析了在单纯温度场、电场和温度场耦合等不同载荷条件下金属引线和合金焊料的热迁移研究.归纳并提出了集成电路微互连结构热迁移研究亟待解决的问题. 关键词: 集成电路 微互连 热迁移  相似文献   

17.
The thermal instability of a layer of Rivlin-Ericksen elastico-viscous fluid in porous medium acted on by a uniform magnetic field is considered. For stationary convection, Rivlin-Ericksen elastico-viscous fluid behaves like a Newtonian fluid. The magnetic field is found to have stabilizing effect whereas medium permeability has destabilizing effect. The magnetic field introduces oscillatory modes in the system, A sufficient condition for the non-existence of overstability is also obtained.  相似文献   

18.
The concepts of uncertainty in prediction and inference are introduced and illustrated using the diffraction of light as an example. The close relationship between the concepts of uncertainty in inference and resolving power is noted. A general quantitative measure of uncertainty in inference can be obtained by means of the so-called statistical distance between probability distributions. When applied to quantum mechanics, this distance leads to a measure of the distinguishability of quantum states, which essentially is the absolute value of the matrix element between the states. The importance of this result to the quantum mechanical uncertainty principle is noted. The second part of the paper provides a derivation of the statistical distance on the basis of the so-called method of support.  相似文献   

19.
The role of strong absorption of particles in intermediate and final states has been considered. The range of applicability of phenomenological models of absorption has been studied. This model is nonuniversal. Its applicability depends on the type of interaction Hamiltonian and matrix element used. We also demonstrate that the violation of the unitarity condition can produce a qualitative error in the results. The absorption (decay) in the final state does not tend to suppress the total process probability as well as the probability of the channel corresponding to absorption. This is true for the reactions, decays and nˉ conversion in the medium.  相似文献   

20.
We prove the existence of chaos in temperature in the Sherrington-Kirkpatrick model. The effect is exceedingly small, namely, of the ninth order in perturbation theory. The equations describing two systems at different temperatures constrained to have a fixed overlap are studied analytically and numerically, yielding information about the behavior of the overlap distribution function PT1(,T2)(q) in finite-size systems.  相似文献   

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