草原垦荒行星边界层的数值研究

本文主要用修改的Nickerson等(1986)提出的中尺度模式,研究了在我国北方(49°19′N,119°55′E)草原开垦地所形成的行星边界层。其基本结果是:1)正午开垦地的“热岛”强度达4—6℃。下垫面的热力扰动可达700m高度,而对流扰动可达行星边界层顶,对流速度为1-2cm·s~(-1);2)一旦草原被大范围开垦,其边界层气候就会朝干热方向演变;3)灌溉可以减轻开垦地的“热岛”强度和旱情,但不能阻止气候的干热化过程,4)行星边界层内局地环流的方向在一昼夜内保持不变,即低层150—200m高度以下的气流由草原吹向开垦地,风速达2m·s~(-1)左右,上层为返回气流,速度略小于下层。草原上的湿气流在水平方向伸入开垦地可达30-50km。     

新疆头屯河地区侏罗系砂岩成分变化及构造环境的探讨

对砂岩矿物成分的定量研究,发现砂岩矿物成熟度的变化与该区构造运动相吻合,源区构造环境为再旋回造山带和岩浆岛弧。     

贺兰山群变质杂岩主期变质作用的温压环境研究

分布于贺兰山脉北部的贺兰山群变质杂岩的主期变质作用达角闪麻粒岩相,其矿物组合特征与低压相系麻粒岩相似、利用共生矿物组合和矿物对的温度计、压力计估算主期变质温度740—764(?),压力460—501MPa。温度压力条件与低压相系的地热梯度线较接近,变质作用强度具面型分布的特征,与东部密云、冀东等地的麻粒岩相区相似,但变质压力明显低,压力类型也不同,应属不同构造背景下的变质产物。     

测站偏心引起垂直角的改正计算

当测站偏心线元素较大时,不仅水平方向需要改正,天顶距也要改正。     

太阳能热水器防雷技术探讨

太阳能热水器因其节能环保，受到人们的青睐。但如果安装不当，在雷雨季节，太阳能热水器很可能会变成“引雷器”。     

Deformation Mechanism and Stability of a Rocky Slope

A high slope is located on the side of the spillway at a hydropower station in Southwest China, which has some weak inter-layers inclining outwards. Parts of the slope show heavy weathering and unloading. There appeared deformation and tensile crack either on the surface or on the afteredge of the slope during excavation, and under a platform （elev. 488 m）, two levels of slopes collapsed on the downriver side. Based on the investigation in situ and the analysis of the geological structure, the conceptual model of deformation and failure mechanism was erected for this slope. Furthermore, the deformation characteristics were studied with FLAC^3D numerical simulation. Comprehensive analysis shows that the whole deformation of the slope is unloading rebound in certain depth scope and the whole body does not slide along any weak interlayer. In addition, two parts with prominent local deformation in the shallow layer of the slope show the models of ＂creep sfiding-tensile cracking＂ and ＂slidlng-tensile cracking＂, respectively. Based on the above analysis, the corresponding project of support and reinforcement is proposed to make the slope more stable.