Slope process change and colluvium deposition in Swaziland: An SEM analysis

Electron microscope analysis of sixty samples taken from six colluvium sites in Swaziland has shown that the quartz grains exhibit marked edge abrasion in the uppermost beds of exposures. This edge abrasion is lacking in the lower beds in all sections examined and indicates slope process change during colluvium deposition. A model of slope evolution is provided, in which slope erosion progressively brings about more channelling and causes greater surface roughness because of the exhumation of more core stones and differentially weathered rock. This roughness causes increased edge abrasion.     

Limestone weathering in Eastern Australia. Part 2: Surface micromorphology study

Results from long term microerosion meter (MEM) studies indicate that microenvironments are characterized by different erosion rates. A complementary study, carried out on the same sites, examines the microscale morphology in each environment. Optical and scanning electron microscopy were used to identify a range of features thought to reflect different processes. Under subaerial conditions micromorphology is dominated by biological weathering features owing to the presence of microflora. Sites permanently covered by soil or stream water have only dissolution etch features, though stream sites may exhibit microfractures. Sites with periodic exposure exhibit both dissolution and biological etch features. The natural environment is more accurately reflected by allowing some microflora colonization of MEM sites rather than preventing colonization by artificial means.     

岩体质量分级的风险分析方法

提出了基于RMR岩体质量分级系统的岩体质量研究风险分析方法。该方法分析步骤如下 :(1)通过岩芯样品的现场观测和实验室试验获得分类所需的变量 ;(2 )统计分析拟合得出各变量的分布函数及参数 ;(3)运用Monte Carlo模拟方法获得 2万个RMR值 ,并将结果绘成岩体质量描述图 ;(4)利用以上结果作出岩体质量风险分析评价。该方法用于润扬长江公路大桥岩体质量评价研究获得良好效果     

煤中显微裂隙的成因类型及其研究意义

分析、归纳了大量的扫描电子显微镜观测结果，以煤岩学、构造地质学研究为基础，依据煤中显微裂隙的形态，大小、排列组合等发育特征，将内生裂隙进一步划分为失水裂隙，缩聚裂隙、静压裂隙，将外生裂隙进一步划分为张性裂隙，压性裂隙，剪性裂隙，松弛裂隙，描述了各类隙的发育特征，探讨了裂隙的演化，识别和影响裂隙发育的因素，裂隙成因类型的研究，有助于判断不同裂隙对煤储层渗透率的贡献。     

The use of GPS arrays in detecting shock-acoustic waves generated during rocket launchings

This paper is concerned with the parameters of shock-acoustic waves (SAW) generated during rocket launchings. We have developed the interferometric method for determining SAW parameters (including angular characteristics of the wave vector, and the SAW phase velocity, as well as the direction towards the source) using GPS-arrays. Contrary to the conventional radio-probing techniques, the proposed method provides an estimate of SAW parameters without a priori information about the site and time of a rocket launching. The application of the method is illustrated by a case study of ionospheric effects from launchings of rockets PROTON, SOYUZ and SPACE SHUTTLE from Baikonur and Kennedy Space Center cosmodromes in 1998–2000. In spite of a difference of rocket characteristics, the ionospheric response for all launchings had the character of an N-wave corresponding to the form of a shock wave. The SAW period T is 270–360 s, and the amplitude exceeds the standard deviation of total electron content background fluctuations in this range of periods under quiet and moderate geomagnetic conditions by factors of 2–5 as a minimum. The angle of elevation of the SAW wave vector varies from 30° to 60°, and the SAW phase velocity (900–1200 m/s) approaches the sound velocity at heights of the ionospheric F-region maximum. The position of the SAW source, inferred by neglecting refraction corrections, corresponds to the segment of the rockets path at a distance no less than 200–900 km from the launch pad, and to the rocket flying altitude no less than 100 km. Our data are consistent with the existing view that SAW are generated during a nearly horizontal flight of the rocket with its engine in operation in the acceleration segment of the path at 100–130 km altitudes in the lower atmosphere.     

Quantitative description of electron precipitation during auroral absorption events in the morning/noon local-time sector

Flux-energy spectra of precipitating electrons are derived from electron density profiles measured by the EISCAT radar during auroral absorption events in the morning/noon local-time sector. The inversion technique uses effective recombination coefficient profiles computed on the basis of a previously validated theoretical model of the lower ionosphere. It is shown that flux-energy spectra for the energy range 30–200 keV are in reasonable agreement with those derived for the same events using trapped flux-energy spectra from geosynchronous satellite data and a model for diffusion of trapped electrons into the loss cone by scattering on whistler waves. During individual events, strongly varying precipitating fluxes are found to be due primarily to varying pitch-angle diffusion.     

利用水汽图象分析中尺度云团

利用ＮＯＡＡ卫星提供的水汽图（６．７μｍ），配合ＧＭＳ云图、多普勒雷达照片，分析了中尺度暴雨云团发生的位置、演变及其结构，最后给出了有关方法的预报框图。     

低地球轨道（LEO）的大型航天器充电

本文根据ＬＥＯ中等离子体温度低，密度高，德拜长度小的特点，采用薄鞘层近似，计算了离子收集电流；根据电流平衡方程，考虑表面二次电子发射，计算了大型航天器表面在沉降电子流辐照下的充电特性。     

秦皇岛市断裂断层泥的SEM特征与断裂活动性

在野外地质调查的基础上，通过研究秦皇岛市Ｆ１、Ｆ２、Ｆ３断裂断层泥中石英颗粒表面的ＳＥＭ特征，认为Ｆ１断裂最末一次活动时间在早更新世至中更新世；Ｆ２断裂最末一次活动时间在晚更新世中晚期；Ｆ３断裂最末一次活动时间在晚更新世末或全新世初。