陕西蓝田公王岭黄土古土壤序列的磁组构特征及其古环境意义

IEECAS SKLLQG

4π硅球探测器研制的初步结果

简要介绍了4π硅球探测器的设计结构、探测器的制备工艺及性能。

西安地区不同厚度土层土壤co2释放量的差异研究

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在相对论平均场框架下Pr同位素链中滴线核的确定

在相对论平均场框架下研究了Pr同位素链中中子和质子滴线核的可能位置及相关性质 .对效应的处理采用了BCS方法 ,并使用了与同位素有关的对力常数 ,对不成对的核子采用了‘阻塞法’ ,考虑了核的轴对称形变 .计算结果表明 ,对不同物理量的研究都可得到185 Pr为同位素链中丰中子边最后一个稳定核 .而在丰质子边 ,采用本方法很难确定质子滴线核的位置 .原因是由于在丰质子边随着A的减少 ,费米面比丰中子边的费米面更快地趋于连续态 ,BCS方法不再成立 ,并须考虑束缚态和连续态的耦合 .

Void swelling in a 9Cr ferritic/martensitic steel irradiated with energetic Ne-ions at elevated temperatures

In this work the void swelling behavior of a 9Cr ferritic/martensitic steel irradiated with energetic Ne-ions is studied. Specimens of Grade 92 steel (a 9%Cr ferritic/martensitic steel) were subjected to an irradiation of Ne-20-ions (with 122 MeV) to successively increasing damage levels of 1, 5 and 10 dpa at a damage peak at 440 and 570 degrees C, respectively. And another specimen was irradiated at a temperature ramp condition (high flux condition) with the temperature increasing from 440 up to 630 degrees C during the irradiation. Cross-sectional microstructures were investigated with a transmission electron microscopy (TEM). A high concentration of cavities was observed in the peak damage region in the Grade 92 steel irradiated to 5 dpa, and higher doses. The concentration and mean size of the cavities showed a strong dependence on the dose and irradiation temperature. Enhanced growth of the cavities at the grain boundaries, especially at the grain boundary junctions, was observed. The void swelling behavior in similar 9Cr steels irradiated at different conditions are discussed by using a classic void formation theory. (c) 2008 Elsevier B.V. All rights reserved.

Unified fission model for proton emission

The unified fission model (UFM) combining with the phenomenological assault frequency has been carried out to investigate the proton-radioactivity half-lives of spherical proton emitters. The results are in good agreement with the experimental data and other theoretical values, and newly observed spherical proton emitters have been analyzed. Finally, the effect of angular momentum transfer on half-life of proton emission has been discussed in detail and a formula can be used to describe this relationship.

He喷嘴带传输及X-γ符合测量装置

本文介绍了He喷嘴带传输及X-γ符合测量装置对重缺中子远离核作活性分离鉴别的基本原理和技术路线，以及该装置首次在本所在线完成的实验结果。通过对110 MeV ~(16)O+~(185)Re实验主要反应产物的测量，指定出~(195)Bi，~(196)Bi，~(192)Tl的半衰期分别为3.11 ± 0.30，4.39 ± 0.53和10.8 ± 1.8 Min，与文献报道一致，并根据母子体衰变平衡拐点Tm初步分析了~(195)Pb；在110 MeV ~(16)O+~(142)Nd实验中，首次测量了~(153)Er的EC/β~+衰变，得到其下列四条新γ线：188.6，352.3，400.0，451.6 KeV(±0.3KeV)，并指定其寿命值T_(1/2) = 35.3 ± 1.6 Sec，与文献报道的根据α衰变测得的半衰期36 ± 2 Sec一致

FORESTAR:东北地区多目标森林经营的决策支持系统(英文)

我国林业过去曾经实行过大砍大造的方针,导致全国范围的生态灾难和林区的经济困境。当前正在实施的天然林保护工程和退耕焕还林工程是在我国山地森林应用生态系统管理的良好时机。针对长白山地区天然林的保护与经营,我们建立了一个决策支持系统,简称为FORESTAR。它是以林业局为单位、用GIS框架下的森林资源清查数据建立的。最初的版本包括两个子模块:森林采伐设计和森林恢复经营。在每个子模块下,用户可以比较各种决策条件下的效果,以便从中选优。这个决策支持系统可以用来帮助各级林业工作者实现上下一致的、多目标的森林经营管理规划。图2参17。

白喉毒素越膜机理研究进展

白喉毒素与细胞膜上的受体结合后,在受体个导的内吞作用下进入胞内体。综述了20世纪90年代后期至今,有关白喉毒素在胞内体的酸性环境中的特性研究。在酸性环境下,白喉毒素发生变构,T区疏水基团暴露并插入膜中,形成粘性孔道。T区形成的粘性孔道与白喉毒素结合,象分子伴侣一样,保持C区的线性结构,并使C区进入细胞膜。由于对白喉毒素作用机理的理解深入,逐渐产生一些新的应用前景。

长白山北坡主要建群种种群结构及重要值沿海拔梯度的变化(英文)

在长白山北坡海拔700m至1300m,海拔每上升100m设置一样地,共计13个海拔梯度,研究主要建群种种群结构及重要值沿海拔梯度的变化。结果表明:除落叶松之外,其它树种在其核心分布区更新良好,均表现出一个健康发展种群的结构特征。落叶松的重要值沿海拔梯度变化不明显,表现出沿海拔梯度很强的适应性。随着海拔的上升,进入主林层的树种越来越少, 海拔高于1800m时, 岳桦是唯一可以成为建群种的树种,形成了单优势种群落。红松和色木的重要值沿海拔梯度表现出相似的变化规律,表明二者有近的生态适应性。图2表1参10。

Study of a high power density sodium polysulfide/bromine energy storage cell

Nickel catalyst supported on carbon was made by reduction of nickelous nitrate with hydrogen at high temperature. Ni/ C catalyst characterization was carried out by XRD. It was found that the crystal phase of NiS and NiS2 appeared in the impregnated catalyst. Ni/ C and Pt/ C catalysts gave high performance as the positive and negative electrodes of a sodium polysulfide/ bromine energy storage cell, respectively. The overpotentials of the positive and negative electrodes were investigated. The effect of the electrocatalyst loading and operating temperature on the charge and discharge performance of the cell was investigated. A power density of up to 0.64 W cm(-2) ( V = 1.07 V) was obtained in this energy storage cell. A cell potential efficiency of up to 88.2% was obtained when both charge and discharge current densities were 0.1 A cm(-2).