CSR注入引出高压静电偏转板设计

　利用3维电磁场计算程序MAFIA对CSR注入引出静电偏转板的物理结构进行了理论设计。该偏转板高压电极材料采用表面经过阳极氧化处理的锻铝板材,倒角半径为20mm,电极半宽度60mm,其几何形状能够同时满足电场均匀性、耐压性及机械强度的要求,切割板电极采用半钨丝半钽板的结构,入口厚度不大于0.1mm。在设计基础上制造了偏转板模型,并对之进行了真空模拟试验,结果证明该高压静电偏转板的设计方案是合理的,基本满足物理实验要求。

薛定谔猫佯谬与重离子耗散反应激发函数的测量

<正> 量子力学的建立与相对论的提出,是20世纪物理学最伟大的成就,它们构成了现代科学的理论基础,也是当代人类物质文明的理论基础。有趣的是,一方面量子理论已经为无数的实验事实所证实,到目前为止甚至还找不到一个与它的预言相悖的实际事例;另一方面,量子力学的基本概念又与人们对现实宏观世界的传统认知极不协调。这种不协调实质上是对量子理论的根基的质疑。所以,从量子力学诞生前后一直到现在的近百年间,对量子理论的争议一天也没有停止过。其中,最著名的议题之一就是所谓的薛定谔猫佯谬。

Microscopic Three-Body Force Effect on Nucleon-Nucleon Cross Sections in Symmetric Nuclear Matter

We provide a microscopic calculation of neutron-proton and proton-proton cross sections in symmetric nuclear matter at various densities, using the Brueckner-Hartee-Fock approximation scheme with the Argonne V-14 potential including the contribution of microscopic three-body force. We investigate separately the effects of three-body force on the effective mass and on the scattering amplitude. In the present calculation, the rearrangement contribution of three-body force is considered, which will reduce the neutron and proton effective mass, and depress the amplitude of cross section. The effect of three body force is shown to be repulsive, especially in high densities and large momenta, which will suppress the cross section markedly.

A Comparison of the Contribution of Various Gases to the Greenhouse Effect

The current concern about an anthropogenic impact on global climate has made it of interest to compare the potential effect of various human activities. A case in point is the comparison between the emission of greenhouse gases from the use of natural gas and that from other fossil fuels. This comparison requires an evaluation of the effect of methane emissions relative to that of carbon dioxide emissions. A rough analysis based on the use of currently accepted values shows that natural gas is preferable to other fossil fuels in consideration of the greenhouse effect as long as its leakage can be limited to 3 to 6 percent.

喀斯特高原山区的景观格局变化垂直分异性——以贵州省普定后寨地下河流域中下游为例

利用多时相多数据源遥感影像数据(航片、TM影像及SPOT-5影像),采用GIS空间分析技术和数理统计分析相结合的方法,以贵州省普定县后寨地下河流域中下游地区为例,从海拔和坡位2个方面来探讨喀斯特地区的景观格局变化的垂直分异特征。结果表明:林地斑块在海拔范围为1300~1350 m及1450~1550 m的区域内,变化是最大的;水田和旱地斑块在海拔范围为1219~1300 m及1350~1450 m的区域内,变化最大。景观格局在山脊和谷底内变化相对较大,其中变化最大的是林地斑块;景观格局在陡坡和缓坡地区的变化相对较小,但是也存在一定的变化,该区域中变化较大的为水田和旱地斑块。在海拔范围为1300~1500 m的山脊和谷底区域内,景观斑块类型发生的变化较大。该区域应作为喀斯特高原山区的生态环境保护特别关注的区域。

辽西半干旱地区主要作物耗水规律的初步研究

辽西半干旱地区主要作物耗水规律的初步研究王仕新刘作新赵焕胤庄季屏（中国科学院沈阳应用生态研究所，１１００１５）ＡＰｒｅｌｉｍｉｎａｒｙＳｔｕｄｙｏｆＷａｔｅｒＣｏｎｓｕｍｐｔｉｏｎｏｆＭａｉｎＣｒｏｐｓｉｎｔｈｅＳｅｍｉａｒｉｄＡｒｅａｏｆＷｅｓｔＬ...

林业与水土保持专家吴钦孝先生论 黄土高原生态环境建设中植被建造的基本原则

黄土高原地处我国东部经济区向西部经济区扩展的一个中间地带 ,在西部大开发中处于开发的前沿。但长期以来 ,因受人为活动的干扰和其特殊的地质地貌和生物气候条件限制 ,生态系统处于极不稳定的状态。改善生态环境 ,治理水土流失 ,离不开林草植被。为了使该区的植被建设能在较快的时间内取得最好的效果 ,我们根据其自然和社会特征 ,结合长期工作的实践和经验 ,提出如下基本原则。1　人工造林种草为主 ,人工种植与飞播、封禁结合原则实行人工造林种草为主 ,人工种植与飞播、封禁结合 ,符合当地林草生产实际 ,有利于尽早实现山川秀美。鉴于黄土高原植被破坏现状 ,显然 ,目前的林草地数量和质量 ,远不足以保护好生态环境 ,因此 ,必须加快植被建设 ,这是提高其整体功能的基础。大力进行植树种草是迅速重建该区植被的主要途径 ,它既可提高植被生产力 ,也有利于对天然林草的保护 ,可在全区各地进行。飞播造林种草可在该区地广人稀或交通不便、有大面荒山荒沙的地方开展。黄土丘陵区和毛乌素沙地飞播已取良好的结果 ,并在同类地区获得较大面积的推广。封山育林育草虽需时稍长 ,但如条件选择适当 ,也可在该区取得较好的效果 ,关键在于选择适宜的地段 ,并在...

文冠果果壳中脂肪酸成分的研究

目的　研究我国特有的药用植物文冠果的果壳中脂肪酸成分。方法　采用气相色谱 -质谱联用技术。结果　确定 2 1种脂肪酸的结构和含量。结论　其中有 8种脂肪酸在该植物中为首次报道

Progress in electrochemiluminescent analysis

The recent progress in electrochemiluminescent (ECL) assay is reviewed. This review begins with the fundamental researches in ECL, including the discovery of new ECL-active species, such as biochemical, organic and metallorganic materials, digital modeling of ECL process, the flow cells used in ECL assay, and electrochemiluminescent sensor. The application of ECL in environmental analysis, immunoassay, nucleotide acid hybridization sensor. The applications of ECL in environmental analysis, immunooassay, nucleic acid hybridization assay, and other aspects are reviewed with the latest references in detail. Finally, the main problems in the further investigation are outlooked, so are its prospects.

电化学发光分析的新进展

电化学发光技术作为一种新的痕量生化分析手段越来越引人注目.介绍了电化学发光基础研究的最新进展,并评述了电化学发光技术的环境分析、免疫分析、核酸杂交分析及其它生化物质测定中的一些最新应用.

Spontaneous assembly of the inclusion complexes of viologen-attached alkanethiols and alpha-, beta-cyclodestrin on gold electrode

Electroactive self-assembled monolayers (SAMs) with well-defined electrochemical responses were prepared by spontaneous assembly of the inclusion complexes (CD/C8VComegaSH) of viologen-attached alkanethiols (C8VComegaSH) and alpha- and beta-cyclodextrin (CD). They were characterized by X-ray photoelectron spectroscopy and cyclic voltammetry. The results demonstrate that the chemisorption process of CD/C8VComegaSH on gold substrate occurs through S-Au bonds, and that the redox sites in SAMs of CD/C8VComegaSH are in a much more uniform environment than those in SAMs of C8VComegaSH.

Antioxidative principals of Jussiaea repens: an edible medicinal plant

Jussiaea repens L. (JRL) is an edible medicinal plant and is also used as a vegetable by the local people in southwestern China. The crude extract and its four fractions derived from JRL were evaluated for the 1,1-diphenyl-2-picrylhydrazyl radical-scavenging ability, hydroxyl radical-scavenging capacity and the potassium ferricyanide reduction property. The ethyl acetate-soluble fraction (EAF) and EAF6 (a subfraction derived from EAF) were the most valuable fraction and subfraction, respectively. Furthermore, bioactivity-guided chromatographic fractionation revealed that three pure compounds greatly contributed to the antioxidant activities. Qualitative and quantitative analyses of the major antioxidant constituents in the extract were systematically conducted by NMR, mass spectral analyses and RP-HPLC. The result demonstrated that rosmarinic acid (2.00 mg g(-1) JRL dry weight) quercetin 3-O-beta-D-glucopyranoside (9.88 mg g(-1) JRL dry weight), and kaempferol 3-O-beta-D-glucopyranoside (1.85 mg g(-1) JRL dry weight) were the major antioxidative constituents in JRL. These compounds are reported for the first time from this plant.