993 resultados para 115-716A


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测量了 3 0MeV/u40 Ar束流轰击115 In反应靶时出射的中等质量碎片(IMF)的能谱 .通过比较在不同出射角度发射的同一种IMF的能谱 ,得到了IMF的发射机制随出射角的演化关系 .在假定运动源速度和出射离子库仑位垒不随出射角变化的条件下 ,通过改变发射源的强度和核温度参量完成了对实验测得能谱的运动源拟合 ,并详细讨论了 3个发射源所占份额和源强随出射角的演化关系 .

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从 2 5MeV/u4 0 Ar+115In反应前中角区出射碎片的能谱、角分布和Z电荷分布出发 ,讨论了碎片发射机制随出射角和核电荷数Z的渐进变化 ;用改进的量子分子动力学 (MQMD)模型研究了碎片角分布及Z电荷分布 ,理论计算和实验值整体上符合较好 ,但在前角区MQMD模型低估了碎片的产额 ,在中角区对于Z接近弹核的碎片 ,理论计算比实验值偏高 ;碎片产物的角分布及Z电荷分布还与统计模型GEMINI进行了比较 ,发现在前角区平衡蒸发的成分所占比例很小 ,中角区所占的比例有所增加 ,但仍然是较小的比例 .随着碎片核电荷数Z的减小 ,平衡核的蒸发成分逐渐减少 ,非平衡的中速成分逐渐占主导地位

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测量了 25MeV/u40 Ar+115 In,58 Ni,27 A1反应前中角区出射碎片的角分布和 元素 Z分布.用改进的量子分子动力学(MQMD)模型研究了碎片的角分布和 Z 分布.理论计算值和实验值整体上符合得很好,但在前角区,MQMD模型低估 了碎片的产额,在中角区对于Z接近弹核的碎片,理论计算值比实验值偏高.碎 片产物的角分布和Z分布还与统计蒸发模型GEMINI进行了比较,结果表明,在 前角区平衡蒸发成份所占的比例很小,中角区所占的比例有所增加,但仍然是较 小的比例.同时发现平衡蒸发成份随着出射碎片核电荷数Z的减小而逐渐减 少.

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The properties of the nuclei belonging to the newly observed nuclei starting from (288)115 have been studied with the generalized liquid drop model connected with WKB approximation. The calculated results have been compared with the results of the DDM3Y theory and the experimental data. The half lives of this new alpha decay chain have been well tested from the consistence of the macroscopic, microscopic and the experimental data.

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本实验使用放射化学方法测定了42 MeV/u (12)C与~(115)In相互作用靶余核的生成截面。借助高斯电荷分布的假设得到了靶余核的质量分布。将实验得到的质量分布与熔合碎裂模型和级联的两体衰变模型进行了比较。特别值得注意的是,使用统计的两体衰变模型Monte Carlo GEMINI程序计算第一次与实验结果符合得非常满意。同时计算结果也表明:在42MeV/u的轰击能量下,完全熔合对靶余核的产物仍然有很大的贡献。在同样的假设下,得到了靶余核的同位素分布。可以看到,同位素分布的宽度随靶余核原子序数的增加而增加,在此对利用中能重离子反应生成新的远离β稳定线的缺中子核素进行了讨论

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用能量密度公式及小液滴模型给出的费米密度分布,并引入中子皮及中子分布弥散度随中子过剩自由度增加而增加这一因素,计算了重离子反应在相互作用势及熔合位垒。熔合位垒的计算值和实验值符合很好,特别是在中重核区域,改善了以前的计算结果。详细研究了亲近势标度,发现用中子皮及中子分布弥散度的变化能较好地解释中子过剩自由度对新近势标度偏离的影响。本工作对奇异核结构与核反应性质的研究无疑是有用的。我们利用HIRFL提供的46.7MeV/u ~(12)C束轰击~(58)Ni、~(115)In、~(197)Au研究了反应中发射的α粒子角分布和能谱。从速度表象中洛仑兹不变截面等高图中明显看到发射α粒子的三个源。用这三个源的运动模型成功拟合了α粒子能谱,所提取的参数符合费米气体模型计算结果,并讨论了能谱及拟合参数对靶的依赖关系。认为快速源实质上来自弹核碎裂或类弹核碎裂

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论文分为两个部分。第一部分:研究在25MeV/u ~(40)Ar+~(115)In反应中轻粒子发射机制。实验中,利用研制的轻粒子探测器测量了发射的P、#alpha#能谱。用三源模型拟合了轻粒子能谱,所提取的参数与费米气体模型的计算结果进行比较,分析了发射源形成和衰变的一些特点。第二部分:研制一种大面积幅度、时间、位置灵敏闪烁探测器。它是HIRFL上建成的第一阶段放射性核束物理实验终端的主要设备之一,在首次放射性核束调试中收到良好的效果。本文的目的是用经典理论研究了热核形成及衰变的一些性质,在即将开展的放射性核束物理研究中, 利用研制的大型探测器对经典理论普适性进行检验

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高原115(原代号96-115号)是中国科学院西北高原生物研究所于1992年以(太谷核不育系*91-233)F_1为母本,{加拿大11号*[繁6*(R211*苦瓜)F_4]F_5}F_5紫黑色小麦为父本进行杂交,采用系谱法选育而成的春小麦品种。2001年12月通过青海省农作物品种审定委员会审定。

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Mammalian group-II phospholipases A2 (PLA2) of inflammatory fluids display bactericidal properties, which are dependent on their enzymatic activity. This study shows that myotoxins II (Lys49) and III (Asp49), two group-II PLA2 isoforms from the venom of Bothrops asper, are lethal to a broad spectrum of bacteria. Since the catalytically inactive Lys49 myotoxin II isoform has similar bactericidal effects to its catalytically active Asp49 counterpart, a bactericidal mechanism that is independent of an intrinsic PLA2 activity is demonstrated. Moreover, a synthetic 13-residue peptide of myotoxin II, comprising residues 115-129 (common numbering system) near the C-terminal loop, reproduced the bactericidal effect of the intact protein. Following exposure to the peptide or the protein, accelerated uptake of the hydrophobic probe N-phenyl-N-naphthylamine was observed in susceptible but not in resistant bacteria, indicating that the lethal effect was initiated on the bacterial membrane. The outer membrane, isolated lipopolysaccharide (LPS), and lipid A of susceptible bacteria showed higher binding to the myotoxin II-(115-129)-peptide than the corresponding moieties of resistant strains. Bacterial LPS chimeras indicated that LPS is a relevant target for myotoxin II-(115-129)-peptide. When heterologous LPS of the resistant strain was present in the context of susceptible bacteria, the chimera became resistant, and vice versa. Myotoxin II represents a group-II PLA2 with a direct bactericidal effect that is independent of an intrinsic enzymatic activity, but adscribed to the presence of a short cluster of basic/hydrophobic amino acids near its C-terminal loop.

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This article focuses on a type of prognostication that bases its predictions on the behavior of the wind during the twelve nights of Christmas and in particular on the relationship between the Old English version in Oxford, Bodleian, Hatton 115, and a fourteenth/fifteenth-century English text in Latin of the same prognostication, which appears in Oxford, Bodleian, Ashmole 345, fol. 69r. The wind prognostication in Ashmole 345 is remarkably similar to the twelfth-century OE version in Hatton 115, fol. 149v, to the extent that one might be tempted to argue for direct transmission, if it were not for the large temporal gap between the two manuscripts and for the fact that the two texts are being transmitted in two different languages. Interestingly the Latin text in A contains an Old English word that may make us reconsider the relationship between the two manuscripts and may shed light on the reception and transmission of Old English and prognostication by the wind between the end of the fourteenth and the beginning of the fifteenth centuries in English monastic centers.

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den Dunnen et al. [den Dunnen, W.F.A., Brouwer, W.H., Bijlard, E., Kamphuis, J., van Linschoten, K., Eggens-Meijer, E., Holstege, G., 2008. No disease in the brain of a 115-year-old woman. Neurobiol. Aging] had the opportunity to follow up the cognitive functioning of one of the world's oldest woman during the last 3 years of her life. They performed two neuropsychological evaluations at age 112 and 115 that revealed a striking preservation of immediate recall abilities and orientation. In contrast, working memory, retrieval from semantic memory and mental arithmetic performances declined after age 112. Overall, only a one-point decrease of MMSE score occurred (from 27 to 26) reflecting the remarkable preservation of cognitive abilities. The neuropathological assessment showed few neurofibrillary tangles (NFT) in the hippocampal formation compatible with Braak staging II, absence of amyloid deposits and other types of neurodegenerative lesions as well as preservation of neuron numbers in locus coeruleus. This finding was related to a striking paucity of Alzheimer disease (AD)-related lesions in the hippocampal formation. The present report parallels the early descriptions of rare "supernormal" centenarians supporting the dissociation between brain aging and AD processes. In conjunction with recent stereological analyses in cases aged from 90 to 102 years, it also points to the marked resistance of the hippocampal formation to the degenerative process in this age group and possible dissociation between the occurrence of slight cognitive deficits and development of AD-related pathologic changes in neocortical areas. This work is discussed in the context of current efforts to identify the biological and genetic parameters of human longevity.