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1.
自从20世纪50年代开始利用微束辐照生物活细胞以来,由于微束独特的辐照特征, 其在生物学、 材料学、 生物医学、航空航天科学、环境科学、地质学、微加工等领域得到了广泛的应用。 在前人大量研究的基础上, 对微束装置及其应用进行总结概括。 展望了微束的发展趋势并简单介绍中国科学院近代物理研究所正在兴建的中高能重离子微束辐照装置。 Collimated proton microbeam has been used to irradiate the biological living cells since 1850s. Due to its unique characteristic in irradiation, microbeam has been extensively applied to many research fields,such as biology, material science, biomedicine,aeronautics and stronautics, environmental science, geology,micromachining and so on. Based on the much research of predecessors, the microbeam facilities and their corresponding applications are summarized in this paper. At last,prospects on the development trend of microbeam are made, and the intermediate energy and high energy heavy ion microbeam irradiation facility being constructed at the Institute of Modern Physics of Chinese Academy of Sciences is briefly introduced.  相似文献   

2.
聚合物材料的快重离子辐照效应   总被引:1,自引:0,他引:1  
简要介绍了快重离子辐照损伤的特点,通过与低电离辐射粒子辐照在聚合物材料中产生的效应的类比论述了快重离子辐照在聚合物材料中产生的效应及其研究现状 ,并结合快重离子辐照效应的应用展望了该领域未来的发展.The irradiation effects in polymers induced by swift heavy ions were reviewed in comparison with that induced by low ionization particles based on the characteristics of swift heavy ion irradiations. It is shown that bond breaking and cross linking, gas releasing, amorphization and carbonization of polymers depend strongly on the electronic energy loss. Besides special effects such as alkynes production, can be induced under swift heavy ion irradiation. The perspectives...  相似文献   

3.
利用高能离子模拟研究反应堆结构材料中的辐照效应   总被引:1,自引:0,他引:1  
简要介绍了载能粒子辐射损伤对反应堆结构材料性能的影响,阐述了载能粒子束特别是高能离子束开展模拟研究的优势,并举例说明了国内利用高能重离子模拟研究反应堆结构材料辐射效应取得的进展。实验结果和理论分析表明,载能离子特别是高能离子辐照非常适合用于模拟研究反应堆结构材料中由粒子辐射引起的材料微观结构和宏观性能变化,是模拟研究反应堆结构材料辐射效应的非常有效的手段。 Radiation damage in structural materials of fission/fusion reactors is mainly attributed to the evolution of intensive atom displacement damage induced by energetic particles ( n, α and/or fission fragments) and highrate helium doping by direct α particle bombardments and/or (n, α) reactions. It can cause severe degradation of reactor structural materials such as surface blistering, bulk void swelling, deformation, fatigue, embrittlement, stress erosion corrosion and so on that will significantly affect the operation safety of reactors. However, up to now, behavior of structural materials at the end of their service can hardly be fully tested in a real reactor. In the present paper, damage process in reactor structural materials is briefly introduced, then the advantages of energetic ion implantation/irradiation especially high-energy heavy ion irradiation are discussed, and several typical examples on simulation of radiation effects in reactor candidate structural materials using high-energy heavy ion irradiations are introduced. Experimental results and theoretical analysis suggested that irradiation with energetic particles especially high-energy heavy ions is a very useful technique for simulating the evolution of microstructures and macro-properties of reactor structural materials.  相似文献   

4.
载能重离子与高能中子在材料中能够产生相似的级联碰撞损伤,加之重离子具有大的离位损伤截面和在材料样品中低的感生放射性,载能重离子束成为模拟先进核能装置内部结构材料辐照损伤的重要手段。HIRFL能区的重离子在结构材料中的射程一般远大于晶粒尺寸,因此能够产生材料体损伤,借助小样品技术可以获得材料力学性能变化(尤其辐照脆化)的有用信息,为探讨材料辐照损伤微结构和宏观力学性能变化的关联提供了重要条件。本文简要介绍了近年来我们基于HIRFL高能离子束开展的聚变堆候选材料辐照损伤的研究,包括低活化钢的辐照脆化行为、氧化物弥散强化(ODS)铁素体钢的结构优化对于抗辐照性能的影响、不同载能粒子辐照条件下铁素体/马氏体钢的辐照肿胀数据的关联,以及高能重离子辐照的钨材料中氢同位素的滞留行为。研究表明,结合特殊的测试技术及数据分析方法,高能重离子可作为核能结构材料辐照损伤研究及评估的有效手段。Because of the similarity in cascade damage structure in materials produced by energetic heavy ions and by fast neutrons, and the high displacement rate and low induced radioactivity of samples by heavy ions, heavy ion beam becomes an important tool to simulate radiation damage by energetic neutrons in materials in advanced nuclear energy systems. The ranges of heavy ions provided by HIRFL (Heavy Ion Research Facility in Lanzhou) are generally much larger than the mean dimensions of grains in alloys candidate to advanced nuclear reactors, and is capable of producing radiation damage in bulk scale. It therefore makes possible the evaluation of change of mechanical properties including the radiation induced embrittlement from the irradiated specimens by using miniaturized specimen techniques. In the present paper, we provide an introduction of our recent studies of radiation damage of materials candidate to future fusion reactors by utilizing heavy ion beams in HIRFL.The studies include issues as follows:ductility loss of RAFM steels causes by high-energy Ne ions, impact of oxide dispersoids on the radiation resistance of ODS ferritic steels, correlation of void swelling of ferritic/martensitic steels under different particle irradiation, and behavior of deuterium retention in tungsten under irradiation with high-energy heavy ions. The results show that high-energy heavy ions can be used as a tool to efficiently investigate or evaluate radiation damage in structure materials if combined with some special test techniques and data analysis.  相似文献   

5.
先进核能系统结构材料辐照性能研究   总被引:2,自引:0,他引:2  
首先简要介绍第一代到先进的第四代核能系统的发展、与核能系统发展密切的抗辐照结构材料研发进展、第四代核能系统结构材料辐照性能研究新方法。第四代核能系统发展中,辐照引起材料性能退化是一个需要研究和解决的瓶颈问题。现有中子源都不能满足第四代核能系统结构材料高剂量中子辐照性能研究的要求。为此,发展了用于核能系统结构材料高剂量辐照性能快速检测加速器重离子辐照方法和第四代核能系统实际辐照工况模拟的重离子与氢和氦三束同时辐照新方法,文中进行了详细的介绍。最后介绍了中国原子能科学研究院核能系统结构材料辐照性能研究现状和近期发展计划。该院在HI-13串列加速器器上建立了多种不同用途的重离子辐照装置、三个独立加速器构成的重离子与氢和氦三束同时辐照实验平台,开展了一系列核能结构材料,例如国产改进型奥氏体钢、CLAM钢、1515钢、钽、钨等的辐照性能的系统测试和研究。为了更好地开展核能结构材料性能研究,从国外引进了一台超导直线加速器和一台可变能量重离子回旋加速器。结合现有2×13 MeV,2×1.7 MV串列加速器、30 MeV和100 MeV质子回旋加速器、高压倍加器,中国实验快堆、中国先进研究堆、微堆等,CIAE将建成一个比较完整和先进的核能系统结构材料辐照实验平台系统供国内外用户使用。This paper introduces briefly the development of nuclear energy systems from the GEN I to the advanced GEN IV, the progress of manufacturing radiation resistant materials associated with the development of nuclear energy systems and the new methods of investigating radiation properties of the structural materials for the GEN IV nuclear energy systems at first. Irradiation induced deterioration of materials properties is a bottle neck problem, which must be investigated and solved for the development of the GEN IV nuclear energy systems. Unfortunately, all the currently available neutron sources cannot meet the requirements of investigating radiation properties of structural materials irradiated by high dose neutron irradiation in the GEN IV nuclear energy systems. Therefore, two new methods of the accelerator heavy ion irradiation that simulates the high-dose neutron irradiation and the triple beam irradiation that mimics the real neutron irradiation environment in the GEN IV nuclear energy systems have been developed. These two methods are introduced in this paper. The present status of the study on radiation properties of structural materials for nuclear energy systems of the new generation and the near future development plan at China Institute of Atomic Energy (CIAE) are described also. The accelerator heavy ion irradiation facilities for different applications and the simultaneous triple beam irradiation platform with three separate accelerators or implanters have been established at the HI-13 tandem accelerator of CIAE. A series of structural materials for nuclear energy systems, such as the home-made modified austenic steel, CLAM steel, 1515 steel, Tantalum, Tungsten, etc. have been tested and investigated systematically. A superconducting linear accelerator and a variable energy heavy ion cyclotron have been imported from abroad for a better performance of the study. Combined with the currently existing facilities of 2×13 MeV and 2×1.7 MV tandem accelerators, 30 and 100 MeV proton cyclotrons, China experimental fast reactor, China advance research reactor, Miniature neutron source reactor, etc. a comprehensive and advanced system of experimental irradiation platform for structural materials of nuclear energy systems will be established in the near future for both domestic and foreign users.  相似文献   

6.
针对未来先进核能装置候选结构材料在高温和应力等条件下抗辐照性能的评价与快速筛选的需求,基于兰州重离子研究装置( HIRFL ) 可提供的离子束流条件,设计制作了国内第一套高温应力材料载能离子辐照装置。该装置由束流扫描及探测系统、高温系统、应力系统、真空冷却系统和远程控制系统等5 部分组成,可以同时提供高温和拉/ 压应力下材料的离子束均匀辐照件,温区覆盖了室温至1 200 °C范围,拉/ 压应力范围为0 ~1176 N,x-y 方向均匀扫描面积可大于40 mmx40 mm。利用该装置,已经成功进行了多次高温和应力条件下载能离子辐照先进核能装置候选材料的实验研究,并取得了初步成果。In order to expedite the evaluation of properties of irradiated materials and the selection of candidate materials for future nuclear energy systems, we developed a specific ion irradiation equipment installed on the Heavy Ion Research Facility of Lanzhou ( HIRFL ) for materials under high temperature and stress. This equipment consists of ion beam scanning and detector system, high temperature load system, stress load system, water cooling system as well as telecommunication and control system. It can supply a wide range of temperature (from room temperature to 1 200 °C ) and stress ( pull / push from 0 to 1 176 N) simultaneously for materials under ion irradiation. The x-y scanning area with high uniformity is larger than 40 mm40 mm. This is the first suit of ion irradiation equipment made in China that can be used to study co-operating effects of high temperature and stress in an irradiated material. It has been successfully used several times for materials irradiations under high temperatures and stress, which proved that the new equipment has very good performances in experiments.  相似文献   

7.
简要介绍了高能重离子在金属材料中引起辐照效应的主要理论 ,特别是与电子能损引起的缺陷产生与演化、离子潜径迹形成、辐照相变以及各向异性塑性形变等效应相应的理论描述.Experimental results showed that, for high energy heavy ion irradiations, electronic energy loss could play a dominant role in damage process in solid materials. In order to explain the experimental phenomena and results, a series of theoretical models based on Coulomb explosion or thermal spike mechanisms have been proposed. In the present paper, more attention was paid to theoretical expressions of high energy heavy ion irradiation induced effects in metallic materials ...  相似文献   

8.
本文系统地评述了中能重离子在铁氧体材料小辐照效应的国际国内研究概况.并指出了利用兰州重离子研究装置(HIRFL)可进一步开展的工作.This paper gives a systemic review on the recent progress in the study of irradiation effects in ferrite induced by energetic heavy ions, and also gives a suggestion thatsome experiments in this field can be carried out further by Heavy Ion Reseach Facility ofLanzhou(HIRFL ).  相似文献   

9.
A state-of-the-art high energy heavy ion microbeam irradiation system is constructed at the Institute of Modern Physics of the Chinese Academy of Sciences. This microbeam system operates in both full current intensity mode and single ion mode. It delivers a predefined number of ions to pre-selected targets for research in biology and material science. The characteristic of this microbeam system is high energy and vertical irradiation. A quadrupole focusing system, in combination with a series of slits, has been designed to optimize the spatial resolution. A symmetrically achromatic system leads the beam downwards and serves simultaneously as an energy analyzer. A high gradient quadrupole triplet finally focuses a C^6+ ion beam to 1 μm in the vacuum chamber within the energy range from 10 MeV/u to 100 MeV/u. In this paper, the IMP microbeam system is described in detail. A systematic investigation of the ion beam optics of this microbeam system is presented together with the associated aberrations. Comparison is made between the IMP microbeam system and the other existing systems to further discuss the performance of this microbeam. Then the optimized initial beam parameters are given for high resolution and high hitting efficiency. At last, the experiment platform is briefly introduced.  相似文献   

10.
离子束辐照通常被认为导致材料产生缺陷, 形成无序结构, 从而破坏材料的性能。 但是, 最近利用离子束辐照碳纳米管的实验显示离子束辐照碳纳米管形成无定形的过程不能用传统的离子束辐照材料的机制来解释, 离子束辐照可导致碳纳米管形成一些自组装结构, 如无定形碳纳米结和碳纳米管连接结等。 研究还发现离子束辐照的碳纳米管薄膜在导电性和场发射性能方面都能得到明显的增强。 Ion beam irradiation is usually thought to induce defects and disordered structures in materials and then to destroy the properties of the materials. However, our recent experiments about the ion beam irradiation on carbon nanotubes(CNTs) indicate that the ion beam modification mechanism of CNTs is completely different from traditional one of bulk materials, and ion beam irradiation can lead to self organized structures in CNTs, such as amorphous junctions and CNT junctions. Moreover, the irradiated CNTs exhibit a improved conductivity and an enhanced field emission.  相似文献   

11.
高压电场浓缩液体物料技术的研究及进展   总被引:3,自引:0,他引:3  
丁昌江  杨军  梁运章 《物理》2004,33(6):435-437
高压电场干燥技术是一种全新的干燥技术 .文章对高压电场浓缩液体的机理进行了探讨 ,认为是内部离子注入、非均匀电场和外部离子风吹动三合一的结果 .通过以自来水、葡萄糖酸钠溶液等液体物料为样品 ,首次在高压电场下进行浓缩实验 ,表明高压电场能够加速水分子的脱出 .文章对当前的研究状况进行了介绍  相似文献   

12.
Swift heavy‐ion irradiations of a wide variety of materials have been used to modify and manipulate the properties of solids at the nanoscale. Recently, these high‐energy irradiations have been successfully combined with high‐pressure experiments. Based on results obtained for zircon (ZrSiO4), this paper introduces this new experimental approach involving diamond anvil cells and large ion‐accelerator facilities. This technique provides a wide spectrum of geoscience applications from nanoscale simulations of fission‐track formation under crustal conditions to phase transitions of radiation‐damaged minerals resulting from meteorite impact.  相似文献   

13.
Intense beams of protons and heavy ions have been observed in ultra-intense laser-solid interaction experiments. Thereby, a considerable fraction of the laser energy is transferred to collimated beams of energetic ions (e.g. up to 50 MeV protons; 100 MeV fluorine), which makes these beams highly interesting for various applications. Experimental results indicate very short pulse duration and an excellent beam quality, leading to beam intensities in the TW range. To characterize the beam quality and its dependence on laser parameters and target conditions, we performed experiments at several high-power laser systems. We found a strong dependence on the target rear surface conditions allowing to tailor the ion beam by an appropriate target design. We also succeeded in the generation of heavy ion beams by suppressing the proton amount at the target surface. We will present recent experimental results demonstrating a transverse beam emittance far superior to accelerator-based ion beams. Finally, we will discuss the prospect of laser-accelerated ion beams as new diagnostics in laser-solid interaction experiements. Special fields of interest are proton radiography, electric field imaging, and relativistic electron transport inside the target.  相似文献   

14.
温压结合超高压处理对芽孢杀灭作用的研究进展   总被引:3,自引:0,他引:3       下载免费PDF全文
 详细介绍了温压结合超高压杀菌技术的优点,指出其独特的应用优势,深入完整地综述了温压结合超高压处理对各类细菌芽孢的杀灭作用及动力学研究成果,并对温压结合超高压处理杀灭芽孢的机理做了初步总结。在此基础上,分析了该研究领域尚存在的问题,提出了未来的研究重点和方向。  相似文献   

15.
实现室温超导一直是人们长期追寻的梦想,寻找和合成出具有室温超导性的新材料已成为 凝聚态物理学家和材料物理学家的“圣杯”。近年来,随着理论和实验相继发现超导临界温度高于 200 K 的 H3S 和 LaH10,氢基超导体已逐渐成为实现室温超导的最佳候选,成为物理学、材料科 学等多学科研究的热点领域之一。在本文中,我们将概述超导材料的发展历史和几种典型超导材 料,重点介绍当前高压下氢基超导体的研究进展及面临的挑战,详细讨论中低压力范围氢基高温 超导体的设计思路,展望氢基超导体在低压甚至常压下实现高温乃至室温的可能性。  相似文献   

16.
Bubble detectors which are commonly used as neutron detectors have been demonstrated through this study to be good detectors for registration of high energy heavy ion tracks. Large size bubble detectors made in China Institute of Atomic Energy were irradiated to heavy ions Ar and C up to 650 MeV/u and 400 MeV/u, respectively. Very clear features of stringy tracks of high energy heavy ions and their fragmentations are manifested and distinguishable. A single track created by a specific high energy heavy ion is composed of a line of bubbles, which is visible by naked eyes and retained for months wihhout reduction in size. The creation of heavy ion tracks in bubble detectors is governed by a threshold whose essence is approximately a critical value of energy loss rate (dE/dX)c similar to that of etch track detectors. Ranges of heavy ions in bubble detectors are apparent and predictable by existing formulas. Identification of high energy heavy ions and the applications to heavy ion physics, cosmic rays, exotic particles and cancer therapy monitoring are obviously promising. The experimental and theoretical aspects of high energy heavy ion tracks in bubble detectors as well as the expectable applications are presented and discussed.  相似文献   

17.
空间辐射尤其是高能重离子辐射可造成生物机体的严重损伤, 所以对高能重离子进行恰当的辐射屏蔽, 成为实现载人航天的关键性因素之一。 研究表明, 由于高能重离子与不同屏蔽材料发生相互作用, 所产生的核碎片等次级粒子, 直接影响空间辐射屏蔽材料的屏蔽性能研究和屏蔽结构设计。 介绍了太空辐射的分类与组成, 综述了国际地基辐射屏蔽材料与实验现状。 根据文献中的地基实验数据, 重点描述了被动式屏蔽方法: 以相近能量多种重离子, 不同能量的56Fe和28Si重离子分别与C, H, Al和Cu材料相互作用的总反应截面和碎片产生截面, 并结合510 MeV/u 56Fe与不同厚度CH2相互作用产生的碎片通量分布、 碎片平均LET分布和不同厚度CH2的单位入射离子剂量减少量等方面, 系统讨论分析了C, H, Al, Cu和CH2等常用空间辐射屏蔽材料的屏蔽性能。 Cosmic radiation, particularly the high energy heavy ion radiation, may cause serious injury on living organism. Therefore, it is one of critical restriction factor in Manned Spaceflight. Studies show that high energy heavy ions interacting with the shielding materials can produce numerous kinds of fragments and secondaries. These particles have a direct impact on evaluation of shielding properties of different shielding materials, the optimal shielding structure design and low dose evaluation after shielding materials. From perspectives of divisions of cosmic rays and passive shielding methods, this paper introduces the ground based research of shielding materials. The passive shielding method was discussed, based on the experimental data of the total cross sections and fragment(production) cross sections of the aspects of different heavy ions with approximately same energy and 56Fe, 28Si heavy ions with different energies on H, C, CH2, Al and Cu radiation shielding materials. In addition, the fragment fluency distribution, the average LET distribution and the dose reduction per particle of 510 MeV/u 56Fe in different depth of CH2 material were also discussed.  相似文献   

18.
 指出Johnson-Cook(J-C)、Zerilli-Armstrong(Z-A)、Bodner-Parton(B-P)本构方程在一定条件下的适用性,表明对于低压、高应变率实验,单一曲线假定似乎可以采用。通过等效应力、等效应变,可以将不同应力状态下的流动应力函数采用统一的方程描述。然而,这些本构方程的确立,并不包括平面冲击波实验。对适合于平面冲击波实验的Steinberg-Cochran-Guinan(SCG)本构方程,讨论了其方程中所包含的高压与高应变率耦合效应。指出,以剪切模量度量的流动应力具有应变率相关性。基于温度效应的新发现以及直接测量平面冲击波流动应力的新进展,分别用J-C本构及SCG本构方程估算了钨材料在高压、高应变率加载下的流动应力。结果表明,采用J-C本构估算的流动应力仅在压力为10 GPa以下才能与实验数据相近,当压力高于10 GPa时,流动应力只能采用SCG本构估算。也指出了高压、高应变率本构方程与低压、高应变率本构方程所对应的不同物理背景。  相似文献   

19.
Abstract

The effect of pressure on the luminescence spectrum of the weak field system Cr3+ : LiTaO3 is presented. By using pressure to induce a low to high crystal field strength transition, we demonstrate the ability of pressure to identify distinct dopant bonding environments in luminescent materials.  相似文献   

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