6 resultados para 51-417

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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于2010-11-23批量导入

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本文主要研究了~(14)N+~(51)V(E_n = 94.6 MeV, 86.83 MeV, 79.2 MeV)的耗散碰撞,是上述系统性研究工作的一个重要组成部分。对N+~(51)V系统的DIC反应作了比较详细的研究,给出了类弹产物质心系维辛斯基图,不同出射道及不同TKEL下的角分布,以及不同TKEL不的电荷分布。从这些实验结果中提取全弛豫动能,相互作用时间,及电荷分布的一次矩,二次矩。讨论了~(14)N+~(51) 耗散碰撞随相互作用时间的推移的演化过程,定性分析了壳效应对N+V反应中电荷漂移的影响。同时还指出N+V反应中α集团效应的影响是不重要的,为~(16)O+~(27)Al 研究中提出的强α集团效应对其DIC过程有影响这一观点提供了旁证。最后提取了准弹截面,DIC截面,从而导出全熔合截面,讨论了DIC反应对轰击能的依赖关系

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利用近物所1.7米回旋加速器加速出的97MeV的~(16)O束流轰击~(51)V靶,九组不同的望远镜系统用于对~(16)O + ~(51)V反应中击射α粒子进行单举测量及α粒子与类弹产物符合测量。所有的探测器组号通过电子学线路和近物原的MODAS 1数据获取系统以事件方式记录在磁带上,实现了42参数同时获取。与此同时,利用所提供的束流,完成了CsI(Tl)晶体phoswich探测器的调试工作,得到了好的结果。在VAX/11-780计算机上用PAX数据分析程序对实验数据进行离线分析,得到了α粒子单举能谱、角分布,E-O平面内d~2σ/dEαΩ等高图和速度平面内d_2σ/PCdEdΩ截面等高图;得到了复合核蒸发和直接α粒子发射的截面值。同时也得到了α粒子——类弹产物符合的α粒子能谱和前方向击射α粒子与类弹产物符合的两维能量联图。为了对直接机制中予平衡发射α粒子的贡献有一估计,用激子模型对~(16)O + ~(51)V反应系统进行了理论计算,得到了复合核蒸发及予平衡发射α粒子产额占总产额中所占的比份。实验结果和理论分析表明:除复合核蒸发和予平衡发射的贡献外,还有其它反应机制的存在。通过二体和三体运动学对所得到的符合实际数据进行分析,证明了类弹、类靶跟随发射和弹核破裂(break-up)机制的存在。综合所有的实际结果,我们认为:~(16)O + ~(51)V反应系统中α粒子主要采源于复合核的蒸发和予平衡发射机制,除此而外还应包括类弹、类靶发射和弹核破裂等反应机制的贡献

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According to two times investigation on Scarabaeoidea of Huitong secondary Cunninghamia lanceolata forest in early spring,summer, the number of species Scarabaeoidea in early spring,and summer is 23 and 24,respectively; the Shannon diversity index is 2.067 and 2.417, respectivety; the Shannon evenness is 0.659 and 0.761.In early spring, the dominant species are Malatera horosericea,Melolontha frater and Granida albosparsa.In summer, The dominant species are Anomala vividana, Anomala alabopilosa and Anomala lucens.The species abundance distribution of Scarabaeoidea in two different seasons is fitted in to logarithmic series distribution. A small number of species often become dominant in different seasons.

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The two gadolinium (Gd) polyoxometalates, K-15[Gd(BW11O39)(2)] [Gd(BW11)(2)] and K-17[Gd(CuW11O39)(2)] [Gd(CuW11)(2)] have been evaluated by in vivo and in vitro experiments as the candidates of potential tissue-specific magnetic resonance imaging (MRI) contrast agents. T-1 relaxivities of 17.12 mM(-1) . s(-1) for Gd(BW11)(2) and 19.95 mM(-1) . s(-1) for Gd(CuW11)(2) (400MHz, 25 degrees C) were much higher than that of the commercial MRI contrast agent (GdDTPA). Their relaxivities in bovine serum albumin and human serum transferrin solutions were also reported. After administration of Gd(BW11)(2) and Gd(CuW11)(2) to Wistar rats, MRI showed longer and remarkable enhancement in rat liver and favorable renal excretion capability. The signal intensity increased by 37.63 +/- 3.45% for the liver during the whole imaging period (100 min) and by 61.47 +/- 10.03% for kidney within 5-40 min after injection at 40 +/- 1-mu mol . kg(-1) dose for Gd(CuW11)(2), and Gd(BW11)(2) induced 50.44 +/- 3.51% enhancement in the liver in 5-50-min range and 61.47 +/- 10.03% enhancement for kidney within 5-40 min after injection at 39 +/- 4 mu mol . kg(-1) dose. In vitro and in vivo study showed that Gd(BW11)(2) and Gd(CuW11)(2) are favorable candidates as tissue-specific contrast agents for MRI.

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由于MCS-51系列微控制器存在着硬件堆栈小的结构缺陷,无法满足多任务环境下进行任务切换的需求,因此很难将uC/OS—II移植到MCS-51系列微控制器上。本文给出的"堆栈映射"方式很好的解决了这个问题。同时还对uC/OS—II移植过程中一些关键性问题给予了详细的论述。包括:uC/OS—II可移植的条件、内核配置和裁剪以及内核调试。