大渡河丹巴水电站长大深埋软岩各向异性及宏观力学参数研究

研究了层状岩体各向异性以及宏观力学参数分析方法,提出基于大型岩土分析软件ADINA各向异性材料模块,采用分区分级宏观力学参数模拟分析方法,结合“代表单元体”理论思想,对丹巴水电站二云片岩进行了各向异性模拟和宏观力学参数分析,研究得到丹巴片岩不同片理倾角宏观力学参数以及各向异性特征变化规律。研究结果显示,丹巴二云片岩尺度增加,平行片理向、垂直片理向变形模量 、 收敛幅度不同步, 变化幅度随倾角增大而增大,收敛速率更高,水平向变形模量 趋势较平缓,泊松比的变化规律恰好与之相反;随片理面倾角增大,丹巴二云片岩力学参数趋于极限值规律明显。     

安徽地区地震波衰减、场地响应及震源新参数的测定

根据安徽数字地震台网7个地震台的143条波形资料,研究了安徽地区的衰减模型和各台站的场地响应。采用三段几何衰减模型拟合,得到了安徽及邻近地区的几何衰减函数,得到安徽地区非弹性衰减Q值随频率f的关系为Q(f)=235.3×f0.616;7个台站的场地响应均无明显的放大效应,这与它们均处于岩石地基相符;并在本地区地震预测研究中尝试使用新参数,进行了初步的应用。     

98.7特大暴雨低涡的螺旋度和动能诊断分析

“98．7”特大暴雨过程与700hPa低涡切变线的强烈发展以及丰沛的水汽和强垂直运动密切相关。螺旋度的诊断结果揭示,与强暴雨区和切变线低涡相应的是一对符号相反而又紧邻的螺旋度带。它们的垂直结构是一对符号相反而又互伴的螺旋度柱;螺旋度及其诸分量的量级是相同的。这表明,垂直运动的水平切变和水平速度的垂直切变以及水平速度的水平切变对螺旋度有相同大小的员献,也意味着强垂直运动和低空急流对暴雨的发生和发展极其重要。动能的诊断结果显示。强动能区与暴雨区和低涡切变线有很好的对应关系,在中、低空的强动能中心也正是强降雨中心;动能最强的700hPa也是低涡切变线发展最强的层面。强动能及其强梯度区和强螺旋度区基本一致。表明强动能及其强梯度对螺旋度变率及其通量有重要贡献。     

天津地区覆盖层土动力学参数统计分析

收集天津地区近年来有代表性的具有完整土动力学参数作为实验数据的地震安全性评价报告66份,用两种统计方法按不同深度统计分析粉质黏土、黏土、粉土、砂土、淤泥质土等的实测土动力学参数,给出动剪切模量比和阻尼比平均值。选取2个典型工程场地,构建土层分析模型,进行土层地震反应分析计算。结果表明,本文得到的统计2值在天津地区具有一定的代表性和适用性,与实测值结果更为接近。对于获得原状土样困难的场地,特别是对于较薄的夹层土,可参照统计2结果进行分析计算。     

Genetic Programming Approach for Predicting Surface Subsidence Induced by Mining

INTRODUCTIONThe study of surface subsidence resulting fromunderground mining holds significance in view ofbeneficial effects on national economy and people’sliving conditions.As is known,a large quantity ofminerals need to be exploited for modernization con-struction.Mining leads to surface subsidence,someunderground engineering and production facilities aredestroyed accordingly,which blocks the developmentof production and retards people’s living standard.To solve this contradiction,su…     

Dark haloes of spiral galaxies: ISO photometry

We exclude hydrogen-burning stars, of any mass above the hydrogen-burning limit and any metallicity, as significant contributors to the massive haloes deduced from rotation curves to dominate the outer parts of spiral galaxies. We present and analyse images of four nearly edge-on bulgeless spiral galaxies (UGC 711, NGC 2915, UGC 12426, UGC 1459) obtained with ISOCAM (The CAMera instrument on board the Infrared Space Observatory ) at 14.5 and 6.75 μm. Our sensitivity limit for detection of any diffuse infrared emission associated with the dark haloes in these galaxies is a few tens of μJy per 6 × 6 arcsec² pixel, with this limit currently set by remaining difficulties in modelling the non-linear behaviour of the detectors. All four galaxies show zero detected signal from extended non-disc emission, consistent with zero halo-like luminosity density distribution. The 95 per cent upper limit on any emission, for NGC 2915 in particular, allows us to exclude very low mass main-sequence stars ( M  > 0.08 M⊙) and young brown dwarfs (≲1 Gyr) as significant contributors to dark matter in galactic haloes. Combining our results with those of the Galactic microlensing surveys, which exclude objects with M  < 0.01 M⊙, excludes almost the entire possible mass range of compact baryonic objects from contributing to Galactic dark matter.     

The abundance and radial distribution of satellite galaxies

Using detailed mock galaxy redshift surveys (MGRSs) we investigate the abundance and radial distribution of satellite galaxies. The mock surveys are constructed using large numerical simulations and the conditional luminosity function (CLF), and are compared against data from the Two Degree Field Galaxy Redshift Survey (2dFGRS). We use Monte Carlo Markov chains to explore the full posterior distribution of the CLF parameter space, and show that the average relation between light and mass is tightly constrained and in excellent agreement with our previous models and with that of Vale & Ostriker. The radial number density distribution of satellite galaxies in the 2dFGRS reveals a pronounced absence of satellites at small projected separations from their host galaxies. This is (at least partly) owing to the overlap and merging of galaxy images in the 2dFGRS parent catalogue. Owing to the resulting close-pair incompleteness we are unfortunately unable to put meaningful constraints on the radial distribution of satellite galaxies; the data are consistent with a radial number density distribution that follows that of the dark matter particles, but we cannot rule out alternatives with a constant number density core. Marginalizing over the full CLF parameter space, we show that in a ΛCDM concordance cosmology the observed abundances of host and satellite galaxies in the 2dFGRS indicate a power spectrum normalization of  σ₈≃ 0.7  . The same cosmology but with  σ₈= 0.9  is unable to match simultaneously the abundances of host and satellite galaxies. This confirms our previous conclusions based on the pairwise peculiar velocity dispersions and the group multiplicity function.     

金刚石定位排布钻头设计

对孕镶金刚石钻头中的金刚石定位排布方式和参数进行了分析,设计、制造出40/45目和50/60目金刚石定位排布钻头。在广西横县孟村矿区的钻进试验中,40/45目金刚石钻头的寿命是普通钻头的1.84倍;50/60目金刚石钻头的寿命是普通钻头的2.74倍,时效提高19.7%。     

不同pH值下的珊瑚养殖实验

本文建立了一种科研用室内珊瑚养殖中新生长珊瑚的培植方法,解决了养殖珊瑚中新生长珊瑚样品的培植和采集问题。按照所改进的珊瑚养殖技术和建立的新生长珊瑚的培植方法完成了在不同海水pH值环境下的珊瑚养殖实验,同时达到对养殖中研究参数控制的简化和有效地目的。测定了在养殖过程中各水化学参数的变化,获得了新生长的珊瑚样品,为利用硼同位素组成指示海洋环境的变化提供载体。