用FY85－Ⅲ型立体定向仪和PHOENIX计算器实行颅内异物定位

本文阐述了应用ＦＹ８５－Ⅲ型立体定向仪辅以ＥＬ－５０６Ｈ计算器对颅内异物的三维空间坐标值进行逻辑编程处理实行颅内异物定位的方法。     

Physical Model Tests on the Effect of Anchoring on the Splitting Failure of Deep Large-Scale Underground Rock Cavern

Geotechnical and Geological Engineering - A set of splitting cracks often occur in the high side wall of the deep underground hydropower station due to the excavation-induced unloading during the...     

中国钼矿资源特征及其成矿规律概要

中国钼矿资源丰富,是我国的优势矿种之一.近年来钼矿找矿成果突出,钼矿在我国遍地开花,呈现出“面型”分布的特征.从地理分布上看,总体集中在中国东部地区,其中河南省钼储量居首;从矿床规模看,查明的超大型钼矿床约占全国钼资源量的53％,大型钼矿床约占30％,中型钼矿床约占14％,小型钼矿床和钼矿(化)点仅占约3％;从矿床类型来看,主要有斑岩型、矽卡岩型、热液(脉)型和沉积(变质)型,分别占钼总资源量的85.75％,8.83％,2.79％,2.63％.根据辉钼矿Re-Os同位素年龄将中国钼成矿期划分为六个阶段:前寒武纪(＞800Ma)、寒武纪—志留纪(540～415Ma,加里东期)、泥盆纪—二叠纪(400～290Ma,海西期)、三叠纪(260～200Ma、印支期)、侏罗纪—白垩纪(195～70Ma、燕山期)和古近纪—新近纪(65～10Ma、喜马拉雅期),其中燕山期是最主要的成矿期,形成了约76.69％钼资源,其次为喜马拉雅期.本文初步总结了中国钼矿的时空分布特征及其成矿规律,将全国钼矿划分为41个Ⅲ级成钼带,13个Ⅱ级成钼省,4个Ⅰ级成钼域,建立了中国钼矿成矿谱系,探讨了不同类型钼矿的时空演化、钼成矿作用与构造演化的关系,并认为钼是反映中国地壳演化的有效示踪剂.     

Geochemical mechanism of alkali metasomatism and formation of iron deposits

Discussed in this paper are the processes of albitization and iron activation during the formation of iron deposits, the transport and hydrolysis of iron, chemical reaction characteristic of wall-rock alteration responsible for the localization of iron deposits, the dynamic factors affecting these reactions and systematic variations in pH of ore-forming solutions. A metasomatic series of Na→ Ca→ Fe is noticed when diorite and dark minerals + anorthite + quartz react with 1–3m NaCl solutions at 400°–500°C. Hydrolysis of FeCl₂ has been experimentally studied as a function of temperature and pressure. It is suggested that the pH of ore-forming solutions varies in the direction of alkalic→intermediate→acid→intermediate←kalic from early to late stages.     

A new model for analyzing nonlinear torsion behavior of concrete filled steel tube columns with rectangular section

An experimental study on concrete filled steel tube columns with rectangular section subjected to compressionflexure-torsion combined action has been carried out. The failure modes and load-deformation hysteretic relations were obtained. Based on the principles of classical material mechanics, the relations between the torsion curvature of the section and the shear strain of the fiber on the section were established. Then the strain distribution on the rectangular section of concrete filled steel tube columns subjected to torsion was analyzed. The three-dimensional refined finite element model was also built, in order to make the precision verification. The matrix forms of the relation between the torsion curvature of the section and the shear strain of the fiber on the section were derived, and introduced into the fiber beam model considering nonlinear torsion effect on the section. The comparison between test results and calculation results showed that the fiber beam model considering nonlinear torsion effect had high modeling efficiency and solution precision for predicting the torsion behavior of concrete filled steel tube columns with rectangular sections, and was suitable for analyzing the dynamic response of various structures subjected to the combined cyclic load caused by the earthquake load.     

Characterization of the mechanical properties of a claystone by nano-indentation and homogenization

Based on the analyses of mineralogical compositions by X-ray diffraction and microstructure by optical microscopy, the Young’ modulus and hardness of a claystone were characterized by the nano-indentation technique and homogenization method. Three distinct microstructural zones are identified in the claystone: clay matrix, a composite matrix of clay and small mineral grains and imbedded quartz grains. The elastic modulus and hardness of different zones were determined by nano-indentation testing. Based on the statistical analysis of nano-indentation results, the spatial mappings and frequency distributions of elastic modulus and hardness of the different zones were obtained. The elastic moduli of main constituent phases of the claystone are then estimated from the nano-indentation tests. These values were further used for the determination of the macroscopic elastic modulus of the claystone using two different homogenization schemes: the dilute scheme and Mori–Tanaka scheme. The predicted values by the homogenization schemes are compared with experimental data obtained from conventional uniaxial compression tests.     

塔里木盆地北部油气运移二维二相数值模拟分析

油气运移和聚集过程实际上是油（气）水饱和度知疏导层的变化过程，盆地中油（气）二相流动问题的研究就是对这一过程的定量描述，本项研究是在前人工作基础上，考察压实作用造成骨架变形来推导新的二维二相流动方程，它容描述异常压力演化与二相流动于一式，在模拟方法上采用有限分析的数值方法，这应用于新疆塔里木盆地北部地区，展示了该区异常压力、含水饱和度弥散状扩散效应以及流速场在地质历史时期动态模拟演化特征；指出了该     

Magnetostratigraphy of the Red Beds in the Hengyang Basin

Abstract This paper discusses the Cretaceous-Tertiary magnetic polarity sequence of the the Hengyang Basin on the basis of magnetostratigraphic study. The age of each stratigraphic unit has been determined with the magnetic polarity time scale combined with ³⁹Ar/⁴⁰Ar dating, thus providing evidence for determining the geological ages of different formations. The authors assign the age of the Dongjing Formation of the Hengyang Basin to Early Cretaceous, the Shenhuangshan Formation to Early-Late Cretaceous, the Daijiaping Formation to Late Cretaceous, and the Dongtang and Xialiushi formations to Palaeocene.