生物多样性保护与利用的主要研究方向

生物多样性是有机界一个无所不包的术语，系指一个生态系统、一个区域乃至整个地球物种（包括动物、植物和微生物）丰富和均匀的程度，它既包含生物之间以及生物与环境之间复杂的相互关系的含义，也反映一个区域的发展规划是否符合客观规律的重要标志。可从遗传样性和生态系统多样性三个不同水平来研究和分析其基本特点，当然，不同水平研究的关系是非常密切的。本文主要介绍其当前的基本情况，研究的战略思想，目标和主要研究内容，     

中国主要自然致灾因子的区域分异

依据１０２种自然致灾因子分布图，以县域为统计单元，建立了全国自然致灾因子数据库。在此基础上，绘制出中国自然致灾因子多度、相对强度、被灾指数图，进而分析了它们的区域分异，为进行中国自然灾害区划提供依据。     

自然电场法剧变场的起因初探及其应用

自然电场法剧变场的起因初探及其应用莫承彬，陈忠献，陆怀成（广西物探队，柳州５４５００５）１问题的提出自然电场法是一种效率高、成本低的简易电法勘探。近年来，自然电场法已由金属矿的普查发展到油气储集层勘探、地热开发及水文地质等新领域的应用［１．２］。广西...     

A Preliminary Study on Dust Grains in the Stratosphere

Collected by means of a high-altitude scientific balloon and a self-made automatic sample collector,a total of 276 dust grains were selected for the study of shape,grain size and optical property.Some of the grains were examined by X-ray diffraction and electrom microprobe techniques,The stratospheric dust grains can be classified as 6 types:cosmic dusts,cosmic dusts(?),microtektite,natural pollutants,artificial pollutants and the unknown substances.The different types of dust grains have different characters and distinguishing symbols.Widespread in the space of the solar system,cosmic dusts are the initial substances of the solar system and ,to some degree,have recorded a great wealth of information on the early history of the solar system.So they have become one of the important objects in the field of cosmochemistry at present time,Since the 1960‘s,scholars of many countries have collected cosmic dusts both in the space near the earth(using rock ets,space probes and space shuttles)and in the stratosphere (using high-altitude balloons or U-2air planes).According to the shape(the scanning electron microimage),element composition(the energy-dispersive X-ray spectrum)and optical properties of dust grains,the substances in the stratosphere can be classified as 5 types:cosmic dusts,alumina spheroids,terrestrial artificial pollutants,terrestrial natural pollutants and unknown substances(CDPET,1982).     

自然伽玛数字判别法研究沉积微相——以东濮盆地文留地区沙四段为例

本文主要讨论在油区取心井少的情况下,利用自然伽玛测井值研究沉积微相的平面分布的方法,并对中原油田文留区沙四段进行了实际的分析计算和划分,最后作出了该区沙四上段和沙四下段两张微相平面分布图。     

A New Variety of Mineral—Argentian Mercurian Gold

Argentian mercurian gold,golden-yellow in colour,is a variety of native gold containing Ag and Hg,coccurring as hexagonal and tetragonal crystals in hairy,milk-droplet or irregular forms.Its microhardness Hv=91kg/mm^2,equivalent to 3.04on Mons‘scale,and the reflectance is 70.35%(589nm).Chemical analysis gave:Au 56.05-67.33,Ag18.29-31.06 and Hg 10-14.82%,as well as minor Cu.In a few samples Bi or Fe was also detected.The simplified formula is (Au0.52Ag0.36Hg0.09Cu0.02)0.99.X-ray analysis suggests the mineral is of isometric system,with space group=Oh^5-Fm3m,a0=0.40803nm,V=0.06739nm^3,and Z=4.Argentian mercurian gold occurs in a Ag-multimetal deposit at Xiacun,Baiyu County,Sichuan Province,As observed in the mining district,the mineral is distributed along the fissures of the main metallic minerals pyrite,tetrahedrite,chalcopyrite,arsenopyrite,galena,sphalerite,etc.,or in the sulfide veinlets developed in the.fissures of these minerals.Also found in the mineral deposit are native gold,argentite,sulvanite,bournonite,boulangrite,etc.