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大功率电子加速器的辐射灭菌效果研究
在中国科学院近代物理研究所自行研制的大功率电子加速器上,研究了不同辐照剂量的电子束对大肠杆菌、金黄色葡萄球菌和变形杆菌3种微生物的杀灭效果,同时检测了辐照后菌体超氧化物歧化酶(SOD)活性的变化。结果显示:辐照剂量达到2.0 kGy时,可完全杀灭金黄色葡萄球菌,2.2 kGy时可完全杀灭大肠杆菌和变形杆菌;辐照对3种微生物的SOD活性有较显著的影响
气相色谱过程的蒙特卡罗模拟
用蒙特卡罗方法模拟了易挥发化合物的气相色谱微观动力学行为,描述了化合物随气流在固体色谱柱表面的迁移以及吸附-解吸等过程。按气相色谱微观动力学模型编译的计算机程序模拟了超重元素化合物在等温色谱及热色谱的动力学过程,并根据不同实验条件进行了大量计算。计算结果与实验数据较为吻合。讨论了超重元素的半衰期、吸附态的周期、载气流量以及化合物的质量密度等对实验结果的影响及该理论模型的优点和待改进的地方
碳离子束辐照对甜高粱主要性状的影响
利用兰州重离子加速器国家实验室(HIANLL)提供的100MeV/u碳离子束对甜高粱品种BJ0601和BJ0602进行了不同剂量的辐照处理,并用SPSS13.0软件分析了碳离子束辐照剂量和甜高粱主要性状节间数、株高、茎粗、含糖量及单秆重的相关性,试验结果表明:不同的辐照剂量对甜高粱节间数、株高、茎粗、含糖量及单秆重产生了明显的影响,表现出不同程度的相关性。另外,早熟突变株BJ0601-1M2代各节的平均含糖量高于BJ0601,说明碳离子束辐照可能引起甜高粱含糖量的提高
Investigation of excited states in 22Mg via resonant elastic scattering of 21Na+p and its astrophysical implications
The excited states in 22Mg have been investigated by the resonant elastic scattering of 21Na + p.A 4.0 MeV/nucleon 21Na beam was separated by the Center for Nuclear Study (CNS) radioactive ion beam separator (CRIB) and then used to bombard a thick (CH2)n target. The energy spectra of recoiled protons were measured at scattering angles of θc.m. ≈ 172◦, 146◦, and 134◦, respectively. A wide energy-range of excitation function in 22Mg (up to Ex ∼ 8.9 MeV) was obtained simultaneously with a thick-target method, and a state at 7.06 MeV was newly observed. The resonant parameters were deduced from an R-matrix analysis of the center-of-mass (c.m.) differential cross-section data with a SAMMY-M6-BETA code. The astrophysical resonant reaction rate for the 18Ne(α,p)21Na reactionwas recalculated based on the present parameters.Generally speaking,the present rates are much smaller than the previous ones
Research for HIRFL new improvement project
According to the newest matching mode between the two cyclotrons at HIRFL, the beam obit properties were researched, especially for the harm of existing ‘over-magnetic shim’ in SSC as well as the trajectory in the new mode. The results obtained are encouraging
Study of the aberrations of the IMP heavy ion microbeam irradiation system
A high energy heavy ion microbeam irradiation system is constructed at the Institute of Modern Physics (IMP) of the Chinese Academy of Sciences (CAS). A quadrupole focusing system, in combination with a series of slits, has been designed here. The IMP microbeam system is described in detail. The intrinsic and parasitic aberrations associated with the magnets are simulated. The ion beam optics of this microbeam system is investigated systematically. Then the optimized initial beam parameters are given for high spatial resolution and high hitting rates
The Software Design of a Multi-branch,Multi-point Remote Monitoring System for Temperature Measurement Based on MSP430 and DS18B20
This paper present that the system can acquire the remote temperature measurement data of 40 monitoring points,through the RS-232 serial port and the Intranet.System s hardware is consist of TI s MSP430F149 mixed-signal processor and UA7000A network module.Using digital temperature sensor DS18B20,the structure is simple and easy to expand,the sensors directly send out the temperature data.MSP430F149 has the advantage of ultra-low-power and high degree of integration.Using msp430F149,the multi-branch multi-p...中文文摘:文章论述了通过RS-232串口和Intranet网络,来实现对远端的40个温度测量点的监控。系统硬件由TI公司的MSP430F149混合信号处理器和UA7000A网络模块构成。传感器采用数字式温度传感器DS18B20,它将直接得到温度的数字量,结构简单,易于扩展。MSP430F149处理器具有超低功耗和高度集成等优点,利用它构建的多分支多通道温度测量系统功能强大,结构简单,可靠性高,抗干扰能力强。系统客户端软件采用Microsoft Visual C++6.0设计。本监控系统能够很好地完成对4个分支共40个温度测量点的远程实时监控
The guiding effect study of high-current and low-energy electrons through insulating capillary
带电粒子与绝缘体表面相互作用的研究揭示了很多新的物理现象和物理规律,目前该研究领域已拓展到原子物理,固体物理,等离子体物理等领域,特别是促进了纳米材料,超小尺寸半导体芯片制作,固体结构分析等应用领域的发展。本论文介绍了低能高流强电子束与绝缘体相互作用实验平台的建设,包括强流LaB6电子枪,64通道一维位置灵敏法拉第筒,电流电压转换放大器,基于Lab VIEW的数据获取软件系统等。研究了低能高流强电子束与锥形绝缘毛细管之间的相互作用。测量了出射电子的角分布与能谱,研究了入射电子能量、流强对电子传输效率的影响,分析了电子与高电荷态粒子同毛细管相互作用的区别。用低能高流强电子束与等内径弯曲绝缘管相互作用,测量了出射电子的角分布,研究了入射能量与流强对导向效应的影响。研究表明,与高点和态离子相比,电子与绝缘管相互作用有许多新的特性,电子传输效率较高电荷态粒子小1-2个数量级,且能量损失严重。量子反射和多次小角度散射是电子导向的主要原因带电粒子与绝缘体表面相互作用的研究揭示了很多新的物理现象和物理规律,目前该研究领域已拓展到原子物理,固体物理,等离子体物理等领域,特别是促进了纳米材料,超小尺寸半导体芯片制作,固体结构分析等应用领域的发展。本论文介绍了低能高流强电子束与绝缘体相互作用实验平台的建设,包括强流LaB6电子枪,64通道一维位置灵敏法拉第筒,电流电压转换放大器,基于Lab VIEW的数据获取软件系统等。研究了低能高流强电子束与锥形绝缘毛细管之间的相互作用。测量了出射电子的角分布与能谱,研究了入射电子能量、流强对电子传输效率的影响,分析了电子与高电荷态粒子同毛细管相互作用的区别。用低能高流强电子束与等内径弯曲绝缘管相互作用,测量了出射电子的角分布,研究了入射能量与流强对导向效应的影响。研究表明,与高点和态离子相比,电子与绝缘管相互作用有许多新的特性,电子传输效率较高电荷态粒子小1-2个数量级,且能量损失严重。量子反射和多次小角度散射是电子导向的主要原
Study of high-spin states in 165Er
利用能量为42MeV和45MeV的9Be束流轰击160Gd自支撑靶,通过160Gd(9Be,4n)165Er熔合蒸发反应研究了165Er核的高自旋态结构。基于实验测量结果,扩展了基于ν5/2−[523]和ν5/2+[642]准粒子组态的转动带,观测到了连接这两条具有不同宇称的转动带的强电偶极跃迁。利用跃迁分支比,提取了带间电偶极跃迁的约化跃迁概率,并讨论了强电偶极跃迁与八极关联之间的关系。提取了ν5/2−[523]和ν5/2+[642]转动带的顺排角动量和能级能量旋称劈裂值,并进行了简单讨论。</abstract>
<abstract_alternative>High-spin states of 165Er have been studied using the 160Gd(9Be, 4n)reaction at beam energies of 42 and 45 MeV. The previously known bands based on the ν5/2−[523] and ν5/2+[642] configurations have been extended to high-spin states, and electric-dipole transitions linking these two opposite parity bands were observed. Relatively large B(E1) values have been extracted experimentally from the branching ratios, and were attributed to octupole softness. Alignment and signature splitting in energies in the ν5/2−[523] and ν5/2+[642] bands have been extracted and discussed briefly.</abstract_alternative>
<keyword>熔合蒸发反应;高自旋态;电偶极跃迁;八极关联利用能量为42MeV和45MeV的9Be束流轰击160Gd自支撑靶,通过160Gd(9Be,4n)165Er熔合蒸发反应研究了165Er核的高自旋态结构。基于实验测量结果,扩展了基于ν5/2−[523]和ν5/2+[642]准粒子组态的转动带,观测到了连接这两条具有不同宇称的转动带的强电偶极跃迁。利用跃迁分支比,提取了带间电偶极跃迁的约化跃迁概率,并讨论了强电偶极跃迁与八极关联之间的关系。提取了ν5/2−[523]和ν5/2+[642]转动带的顺排角动量和能级能量旋称劈裂值,并进行了简单讨论。</abstract>
<abstract_alternative>High-spin states of 165Er have been studied using the 160Gd(9Be, 4n)reaction at beam energies of 42 and 45 MeV. The previously known bands based on the ν5/2−[523] and ν5/2+[642] configurations have been extended to high-spin states, and electric-dipole transitions linking these two opposite parity bands were observed. Relatively large B(E1) values have been extracted experimentally from the branching ratios, and were attributed to octupole softness. Alignment and signature splitting in energies in the ν5/2−[523] and ν5/2+[642] bands have been extracted and discussed briefly.</abstract_alternative>
<keyword>熔合蒸发反应;高自旋态;电偶极跃迁;八极关
The latent track and degradation properties of polymer films irradiated by high energy Kr ions
本文简要叙述了快重离子在固体材料,特别是聚合物材料中引起的强电子激发效应研究的基本理论、发展历史和研究现状。描述了在兰州重离子加速器上完成的25 MeV/u 86Kr离子辐照叠层聚对苯二甲酸乙二醇酯膜(PET)和聚碳酸酯(PC)膜的实验及结果分析。应用傅立叶红外变换光谱(FT-IR)及X-射线衍射分析(XRD)方法研究了在不同电子能损及不同注量辐照条件下,高能Kr离子在聚合物PET和PC潜径迹中引起的的损伤效应。结果表明:高能Kr离子在聚合物PET、PC膜引起的损伤主要是由于辐照引起的断键及键的重组产生的官能团的降解及非晶化过程,损伤截面存在电子能损阈值,且与官能团的结构有关。 对PET的傅立叶红外变换光谱分析结果给出,电子能损为7.25 keV/nm时,对应官能团吸收峰794 cm-1, 849 cm-1, 1021 cm-1, 1341 cm-1, 1410 cm-1, 1505 cm-1,的损伤截面半径分别为:3.63 nm, 4.70 nm, 4.58 nm, 3.54 nm, 5.17 nm, 5.32 nm。X-射线衍射分析结果表明,PET的非晶化转变截面随离子注量和电子能损的增大而增加,(100)衍射峰的相对强度I/I0随离子注量的增加而指数衰减,对应电子能损为6.62, 6.93, 7.25 keV/nm,其相应的非晶化半径分别为4.86, 5.64, 6.77 nm。 对PC的傅立叶红外变换光谱分析表明,当电子能损比较小,大多数官能团的红外吸收无明显变化,直到当辐照注量为2×1012 ions/cm2 且电子能损比较大时,其绝对吸收强度才发生明显的改变。电子能损为6.37 keV/nm 时,对应官能团吸收峰为519 cm-1, 605 cm-1, 724 cm-1, 1014 cm-1,其损伤截面分别为:13.12, 45.40, 50.21, 56.28 nm2本文简要叙述了快重离子在固体材料,特别是聚合物材料中引起的强电子激发效应研究的基本理论、发展历史和研究现状。描述了在兰州重离子加速器上完成的25 MeV/u 86Kr离子辐照叠层聚对苯二甲酸乙二醇酯膜(PET)和聚碳酸酯(PC)膜的实验及结果分析。应用傅立叶红外变换光谱(FT-IR)及X-射线衍射分析(XRD)方法研究了在不同电子能损及不同注量辐照条件下,高能Kr离子在聚合物PET和PC潜径迹中引起的的损伤效应。结果表明:高能Kr离子在聚合物PET、PC膜引起的损伤主要是由于辐照引起的断键及键的重组产生的官能团的降解及非晶化过程,损伤截面存在电子能损阈值,且与官能团的结构有关。 对PET的傅立叶红外变换光谱分析结果给出,电子能损为7.25 keV/nm时,对应官能团吸收峰794 cm-1, 849 cm-1, 1021 cm-1, 1341 cm-1, 1410 cm-1, 1505 cm-1,的损伤截面半径分别为:3.63 nm, 4.70 nm, 4.58 nm, 3.54 nm, 5.17 nm, 5.32 nm。X-射线衍射分析结果表明,PET的非晶化转变截面随离子注量和电子能损的增大而增加,(100)衍射峰的相对强度I/I0随离子注量的增加而指数衰减,对应电子能损为6.62, 6.93, 7.25 keV/nm,其相应的非晶化半径分别为4.86, 5.64, 6.77 nm。 对PC的傅立叶红外变换光谱分析表明,当电子能损比较小,大多数官能团的红外吸收无明显变化,直到当辐照注量为2×1012 ions/cm2 且电子能损比较大时,其绝对吸收强度才发生明显的改变。电子能损为6.37 keV/nm 时,对应官能团吸收峰为519 cm-1, 605 cm-1, 724 cm-1, 1014 cm-1,其损伤截面分别为:13.12, 45.40, 50.21, 56.28 nm