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Energy instability strongly affects the state and the beam size of the single ion microbeam. A facility based on the Generating Voltmeter was developed to improve the energy stability of the CAS-LIBB (Chinese Academy of Sciences, key laboratory of ion beam bioengineering) single ion microbeam. This paper presents the analysis of the energy' instability of the single ion microbeam. A simplified theoretical model is set up to calculate the relationship between the energy instability and the beam spot size. By using this technique, the energy instability is adjusted to about 1%. Stable run-time is over 6 hours. The radius of the single ion beam is reduced by 10% compared to the previous olin. 相似文献
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经济的发展在于革新和转型,大学的发展也在于改革和创新。大学发展的内涵是转型发展,在转型的过程中,会遇到各种各样的问题,其中包括多元文化冲击。除了主流文化,非主流文化在学生的生活中占据很重要的位置。从多元文化出发,探讨网络文化,学习手段文化和休闲文化等对大学生心理的影响。笔者通过110份抽样调查问卷,把2013级和2015级学生这三方面调查结果进行比对,找出差异,提出在大学转型发展中应对大学生进行正确的思想及心理引导的建议及对策。 相似文献
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四平山岩金矿地质特征与找矿标志探讨 总被引:2,自引:2,他引:0
四平山岩金矿赋存于白垩系上统四平山组地层内由热泉作用形成的硅化带中。矿床根据所产出的标高可分为上、中、下三个含矿层。矿体呈层状、似层状、透镜状,水平产出,为一低品位中型矿床。其矿床成因类型为与火山机制有关的热泉型金矿床。 相似文献
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From the physical changes of an organism and by combining the dissipative structure with the entropy theory we study the entropy variation of organism lying in the opennonequilibrium native state under ion implantation. The result indicates that the ion implantation increases the conformational entropy, restricts the process of the organism's ordering, and leads to a new bio-effect. 相似文献