A THEORETICAL APPROACH TO P_(co_2) EVOLUTION IN THE ATMOSPHERE BASED ON ASSOCIATIONS OF SEDIMENTARY MINERALS

Based on the theory of pH evolution of sea water and the balance between the seawater and the atmosphere the authors discussed the problems about (i) the method ofcalculating P_(CO_2) in the ancient atmosphere with the associations of sedimentary miner-als; (ii) the evolution of P_(CO_2) values in the geologic history; (iii) the relations of thepH evolution of sea water with carbonate precipitations; and (iv) calculation of the pHlimit for some associations of sedimentary minerals and its corresponding P_(CO_2) valuesin the atmosphere. The authors pointed out that though carbonates had deposited little in the Archaean,the content of CO_2 gas in the Archaean atmosphere was very high and was gradually go-ing up to form a thick CO_2 atmosphere. Up to 2600 Ma ago, the P_(CO_2) had reached a gradeof 10- 50 atm. There was a general trend of evolution that from the early Proterozoicera to the present the depositional horizon of carbonate layers was gradually risingand finally surpassed the horizons of clay min     

THE CHEMICAL COMPOSITIONS OF MINERALS IN QINGZHEN METEORITE AND ITS GEOCHEMISTRY SIGNIFICANCE

The chemical compositions of silicate minerals, sulphide minerals and metal Fe-Ni in theQingzhen meteorite were measured by the microprobe analyses. Based upon these chemicalcompositions, the cosmochemical behaviour and characteristics of the existing forms of themajor elements in the Qinzhen meteorite have been discussed. These characteristics show thatunder the S-rich, O-poor, and strongly reducing conditions, the light metal elements, such asCa, Mg, K, Na may form sulphide, and metal Fe-Ni may contain Si and P. However, we con-sider that the light metal-sulphide can be stable in the lower mantle and there are some Siand P in the Fe-Ni core. Finally, an earth core-mantle model is established, where the Fe-Ni core contains some Si and P; the lower mantle is composed of Mg-rich silicate, SiO_2 andsulphide; the upper mantle, of silicate and oxide.     

电子探针自动连续分析硅酸盐中存在问题的研究

目前,电子探针已成为分析硅酸盐样品的一种重要仪器,新型仪器都可以自动连续分析,大大提高了工作效率,可是定量分析的准确度往往不太高,尤其SiO_2经常偏低。我们以剖析SiO_2分析存在问题出发,讨论了造成误差较大的原因并提出克服的方法     

以合成包裹体为腔体进行高温下流体的拉曼光谱原位分析

在冷封口的水热高压容器中 ,合成了组成分别为H2 O 4 2 0wt%CO2 和H2 O 8 4 2wt%CO2 的两种流体包裹体。以此合成的包裹体作为腔体 ,用显微激光拉曼探针测量了其中液态流体在 2 90 0～ 380 0cm-1范围的高温拉曼光谱 ,对其中液态水的氢键随温度的变化进行了讨论。研究结果表明 ,随着温度升高 ,流体中水分子的氢键作用不断减弱。组成为H2 O 4 2 0wt%CO2 的包裹体 ,在 372℃均一为液体 ,均一时 ,水分子的氢键发生了突变 ,均一后 ,氢键受温度的影响比较小 ,到 5 5 0℃它还存在着比较强的氢键作用。组成为H2 O 8 4 2wt%CO2 的流体在 6 0 6℃时由气液两相变为纯气相 ,一直到拉曼光谱测量的最高温度 5 80℃ ,液态水还保持着比较强的氢键作用。     

Increase the Degradation Efficiency of Organic Pollutants with a Radical Scavenger （Cl^-） in a Novel Photoelectrocatalytic Reactor

Photoelectrocatalytic degradation performance of quinoline in saline water was investigated using a new-designed continuous flow three-dimensional electrode-packed bed photocatalytic reactor.It is interesting to find that chloride ion has an obvious enhancement effect rather than a scavenging effect on the photoelectrocatalytic degradation of quinoline,and create a kinetic synergetic effect in the photoelectrocatalytic reactor.     

Ⅰa型金刚石中水的显微红外光谱研究

天然Ⅰa型金刚石在垂直于（100），（110）和（111）三个方面上定向显微红外光谱的定量比较分析表明：水、片晶和C－C键在以上三个方向上所测得的浓度是不相同的。不同方向上水和片晶浓度的变化趋势基本相同，表明样品中水与处晶具有密切伴生的特征。     

Chronology and origin of Au-Cu deposits related to Paleozoic intracontinental rifting in West Tianshan Mountains, NW China

Located between the Tarim platform and Junggar massif, the West Tianshan intraconti-nental rift abuts against the China-Kazakhstan boundary in the west part, borders on the Yilianha-bierga late Paleozoic relic ocean basin and the South Tianshan late Paleozoic ocean basin re-spectively in the northeast separated by the Aibi Lake fault and in the southeast by the fault alongthe southern margin of the Yili massif. During the development and after the close of the WestTianshan intracontinental rifting in the Carboniferous-Permian period, a series of nonferrous andprecious metal mineralizations occurred with the Au-Cu deposits being the most important. Isotopicchronologic study of representative deposits of different types shows that gold-copper mineraliza-tion in the West Tianshan intracontinental rift zone mainly happened during the middle-late Her-cynian Period, among which the Axi volcanic hydrothermal type gold deposit was formed duringthe Carboniferous with a fluid inclusion Rb-Sr isochron age of (339 ± 28) Ma; the Qiabukanzhuotaquartzolite type gold deposit has a Rb-Sr isochron age of (312 ± 46) Ma; the Tawuerbieke por-phyry type gold deposit has a Rb-Sr isochron age of (295 ± 16) Ma; the Jingbulak magmatic liqua-tion Cu-Ni deposit and the Musizaote porphyry type Cu deposit have the forming ages of 300 Ma ±and 250 Ma±, respectively. Analyses of crustal evolution and metallogenetic geological back-grounds of Au-Cu mineralizations in the studied area shows a close correlation with the rifting.     

RAMAN SPECTROSCOPY OF C,H,L AND LL CHONDRITES AND ITS SIGNIFICANCE IN EXPLORING THE FORMATION ENVIRONMENTS OF METEORITES AND THEIR TAXONOMY

The comparison of Raman spectra of the chondrites (C, H, L, LL) has confirmed thatthere exist two types of meteorite carbon: one is the primary carbon present in carbonaceouschondrites (c) and the other is the secondary carbon contained in ordinary chondrites (H, L,LL). The parameter of order (I_G/I_D intensity ratio, similarly hereinafter) of primary car-bon tends to decrease with increasing petrologic type and it can reflect the temperature ofdust carrier at the time plasma gases in the early nebula were condensed to form primarycarbonaceous material and the hydrogen content in primary carbonaceous material. This kindof primary carbonaceous material maybe has not experienced late stage thermometamorphismwithin the parent body of chondrites, indicating that the carbonaceous chondrites wereformed and retained in the low temperature region of the solar system. The parameter oforder of the secondary carbon tends to increase with increasing petrologic type and it can re-flect the degree of graphitization o     

PRELIMINARY STUDY ON MECHANISM OF PLANT ROOTS TO INCREASE SOIL ANTISCOURIBILITY ON THE LOESS PLATEAU

The effects of the root system of trees, shrubs and grasses on the hydraulic andphysical properties of soil and their interrelation with increasing soil anti--scouribility byroots are quantitatively demonstrated in this paper for the first time. Based on the analysisof the leading factors of roots to increase the soil anti--scouribility, a mathematical modelon increasing soil anti-scouribility by roots is established. The value in application of themodel is to explain the mechanism of roots to increase the soil anti-scouribility and toevaluate the increasing effects of soil anti-scouribility by roots in different layers of soilThe calculated results of the values in soil anti--scouribility intensified by roots at variousintensities of rainfall and slopes of the model have higher precision, all of the meanmaximum deviations between the estimated and observed values being less than 1.417 s/g.     

硅藻土表面羟基的漫反射红外光谱(DRIFT)研究

运用傅里叶变换漫反射红外光谱（DRIFT）及氘化技术,研究了硅藻土的表面羟基结构及其在热处理中的变化。