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1.
讨论在网络远程教育中用JavaApplet来模拟C语言程序的运行,对于给定的程序,用Applet来跟踪程序执行的各个步骤,观察变量的值的变化,显示程序的输出结果,学习者可以给出程序的输入值,观察对于不同输入值而导致的程序执行的流程,变量值和输出的变化,通过在网页中嵌入这种Applet,学习者可以像使用一个调试器一样观察程序的执行过程,在一定程度上实现基于Web的程序设计课程的实验。  相似文献   

2.
地球的脉动和现阶段的扩展   总被引:1,自引:0,他引:1  
脉动理论是本世纪初提出来的,最近该理论又得到了进一步的完善和发展,它可以更好地解释构造,岩浆,海平面变化,沉积作用之间的关系。地球的脉动以下列形式表现:火山作用强度,海进一步海退升,降旋回,挤压与扩展的交替、地磁场特征的变化等。  相似文献   

3.
在整个地质工作中,探矿工程所占人员最多,投资最大,施工时间最长。探矿工程效率的提高和质量的改善,主要依赖于技术的进步和组织管理工作,即采用先进的探矿技术和不断完善施工方法。  相似文献   

4.
关于尼格里的岩浆残余溶液的讨论   总被引:4,自引:0,他引:4  
季克俭  王高尚 《地质论评》1994,40(3):193-199
根据岩浆与水的有限混溶,含水岩浆结晶都以固相线温度告终或当固相线温度时未结晶的岩浆全部共结,且岩浆中超过饱和度的多余水在共结前均呈水气相释放,笔者认为,含水岩浆结晶时,在结晶期或结晶期前释放出水气相,并可能成为热液,但不生成由岩浆结晶逐渐演化而成以水为主的残余溶液,因此,尼格里推断的硅酸盐-水的二元相图依据不足,“残余溶液”是不存在的,所以岩浆期后热液成矿理论也是缺乏基础的。  相似文献   

5.
科学技术研究活动,是人类认识世界和能动地改造世界的过程,选题是进行科学技术活动的起始点,它是直接关系到科研工作的成败或者有无价值的具有重大意义的大事,选题正确是科研工作取得成功的必要条件,正如我国一位科学家所说的,选好课题就等于完成了课题的一半,  相似文献   

6.
从目前上海地区已经查明的矿产资源来看,除了金山张堰铜矿具有中等规模的储量之外,其他矿产无论在矿种上,或者储量上,都极其稀少,匮乏。但是,上海地区的地质资源:如地下水,地下含水层储能和地质景观等却十分丰富多采,有的还充满开拓开发潜力,特别是地质景观资源,它将成为上海发展又一个国民经济支柱产业的旅游事业的可靠物质基础之一。  相似文献   

7.
我国产出的砷铅矿族矿物的研究   总被引:3,自引:0,他引:3  
李艺  赖来仁 《矿产与地质》1997,11(5):336-341
砷铅矿族矿物是一族六方晶系的类质同象系列矿物,包括砷铅矿、钒铅矿和磷氯铅矿。砷铅矿呈淡黄色、浅黄绿色和灰白色六方柱状晶体产出,Hm=3.5,D≥6.75g/cm3,一轴晶负光性,N>2,晶胞参数为a0=1.0251nm,C0=0.744nm,Z=2。广西德保矿区产出的砷铅矿的化学成分为(wt.%):PbO74.94,As2O519.53,P2O52.31,CuO0.36,Cl2.41,总量为99.55。云南个旧矿区产出的钒铅矿呈桔红色至红褐色,六方短柱状自形晶,Hm=3.0,Dx=6.95g/cm3,一轴晶负光性,N>2,晶胞参数为a0=1.031nm,C0=0.743nm,Z=2,空间群为P63/m,其化学成分为(wt.%):PbO79.98,V2O518.94,Cl2.61,总量为101.53。广西阳朔产出的磷氯铅矿,呈暗绿色六方柱状晶体产出,Hm=3.5,D=6.98g/cm3,一轴晶正光性,N=2±,平均化学成分为(wt.%):PbO81.64,P2O515.08,As2O50.10,CuO0.20,Cl2.67,总量为99.69。  相似文献   

8.
准噶尔盆地的侏罗系   总被引:9,自引:2,他引:9  
简介了准噶尔盆地周边侏罗系各岩组的沉积特征及所含生物群面貌。根据生物群纵向演变规律和横向对比,将八道湾组的时代归于早侏罗世早期,不排除其底部为晚三叠世的可能;三工河组为早侏罗世晚期至中侏罗世早期;头屯河组与盆地东北缘五彩湾组相当,属中侏罗世晚期。早、中侏罗世准噶尔盆地气候温暖潮湿,盆地边缘以河流沼泽相为主,是重要成煤时期,中侏罗世晚期以后,盆地开始抬升,盆地边缘以河流相为主,气候变干热,除东北缘外,生物贫乏;晚侏罗世时,盆地受燕山运动影响,激烈抬升,边缘形成河流相或山麓河流相粗碎屑沉积,伴随有强烈的火山活动。  相似文献   

9.
钻进工业的技术发展和竞争,促使从事钻探工作的厂商和技术人员致力于钻进工作的高质量、高效率、低成本的探讨和研究,使得近代的钻探设备日臻完善,推广应用多工艺的钻进方法。如:潜孔式、液动式、气动式冲击回转,双管和多管反循环钻进,无岩心钻进等工艺在钻进工业上取到了卓有成效的经济效益,其中作为钻进技术中的主要工艺金刚石钻进,发展得更为迅速,其技术水平向更高阶段迈进。当前高技术水平金刚石钻进工艺,主要包括:长行程钻机,绳索取心钻具,定向钻进及孔内测试仪器和其他配套技术的使用,尤其是含金刚石的超硬材料的出现和金刚石钻头  相似文献   

10.
光合作用是绿色植物通过叶绿体,利用光能的催化反应把二氧化碳和水合成储存能量的一种过程,特别是水在光合作用下,若不能与二氧化碳保持一定比例的平衡,则光合作用不能继续进行,势必影响到作物的产量。因此,若施用抗旱肥料,不仅光合作用得到新的平衡,更由于光照强度大,时间也长,使合成有机物的丰度大为改观。所以,作物若施用新肥,不仅抗旱,还能保产与增收。  相似文献   

11.
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.  相似文献   

12.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.  相似文献   

13.
Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ1 roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003).  相似文献   

14.
HYDROGEOLOGY     
正20141756 Chen Ruige(Mathematical College,China University of Geosciences,Beijing100083,China);Zhou Xun Numerical Simulation of Groundwater Level Fluctuation in a Coastal Confined Aquifer with Sloping Initial Groundwater Level Induced by the Tide(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(7),2013,p.1099-1104,6 illus.,16 refs.) Key words:confined water,groundwater level  相似文献   

15.
正20141408 Cai Jia(Institute of Geology,Chinese Academy of Geological Sciences,Beijing100037,China);Liu Fulai Petrogenesis and Metamorphic P-T Conditions of Garnet-Spinel-Biotitebearing Paragneiss in Danangou Area,Daqingshan-Wulashan Metamorphic Complex Belt(Acta Petrologica Sinica,ISSN1000-0569,CN11-1922/P,29(7),  相似文献   

16.
17.
正20142386An Guoying(China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China)Application of Satellite Remote Sensing in Regional Hydrogeological Investigation:Taking Cenozoic Strata in Wenquan Sheet(1∶250 000)of Karakoram Range as an Example(Geosci-  相似文献   

18.
正20141016An Chengbang(Key Laboratory of Western China’s Environmental Systems,Ministry of Education,Lanzhou University,Lanzhou 730000,China);Zhao Yongtao Lake Records during the Last Glacial Maximum from Xinjiang,NW China and Their Climatic Impli-  相似文献   

19.
正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.)  相似文献   

20.
GEOCHEMISTRY     
正20142002 Wei Hualing(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang065000,China);Zhou Guohua Element Content and Mineral Compositions in Different Sizes of Soil in Tongling Area,Anhui Province(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(11),2013,p.1861  相似文献   

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