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1.
Causes and consequences of cryolitozone environmental contamination by technogenous mercury have been studied in the paper. Measures have been elaborated and methods for increasing ecological safety of the territories affected by mercury- containing mining wastes have been suggested. It has been proved that comprehensive utilization of mercury-containing heaps allows to solve problems of ecological safety with the least economical expenses.  相似文献   

2.
The lunar sample (70017-291) has been examined using TL technique. Its natural TL glow curve has been established. The effective storage temperature and the sunning degree of this sample have been estimated by comparing ours with the results determined by Dr. S. A. Durrani.  相似文献   

3.
辽西义县组发现一新的翼手龙类化石   总被引:6,自引:0,他引:6       下载免费PDF全文
吕君昌  张宝堃 《地质论评》2005,51(4):458-462,i0004
根据产自中国辽宁省西部早白垩世义县组上部、具有不完整头骨的翼手龙类骨架确立一新属新种:李氏始无齿翼龙Eopteranodon lii(gen.et sp.nov.)。从它窄长的头骨且其上、下颌尖长而没有牙齿,短的颈椎椎体上来看,显示了该翼龙与无齿翼龙类相似。始无齿翼龙的肱骨没有像其他无齿翼龙类那样具有弯曲的肱骨三角嵴,而且几乎所有的无齿翼龙类均个体较大。始无齿翼龙的个体较小,两翼展宽约为1.1m左右。腕骨没有愈合,肱骨三角嵴较平直以及第Ⅳ翼掌骨稍微长于尺骨显示了它的原始性,它代表一新的、较原始的、类似无齿翼龙的翼手龙类。  相似文献   

4.
本文记述了一件采自辽西北票四合屯义县组下部东方翼龙的新标本。通过与正型标本的比较,证明东方翼龙为一有效的属,隶属于梳颌翼龙科。根据对新标本的研究,东方翼龙的修订特征应为:两翼展宽不超过1.25m,尺骨与飞行指的第二指节及胫骨几乎等长,第三足庶骨与胫骨长度之比约为0.40。论杨氏东方翼龙在翼手龙类的系统位置@吕君昌$中国地质科学院地质研究所!北京,100037 @高春玲$大连自然博物馆!116023 @孟庆金$大连自然博物馆!116023 @刘金远$大连自然博物馆!116023 @季强$中国地质科学院地质研究所!北京,100037…  相似文献   

5.
1. Introduction The uplift and evolution of the Qinghai Tibet Plateau has been the most important projects for studying the dynamic process of the plateau, and the uplift mechanism and history are the essential problems. Researches have been done extensively in terms of tectonics, sedimentology, geophysics, paleontology, paleoclimate and paleomagnetism for several tens of years. Many evolution models have been suggested but so far none of them have been explained perfectly. In recent years,…  相似文献   

6.
傅慧芳  朱成明 《地球化学》1980,(1):23-30,i001
Crystal. habit and morphological peculiarities of synthetic diamond have been studied at various temperatures and. pressures.A diagram has been proposed based on experimental data for different erystal morphology with respect to different P.T conditions, Preliminary discussion has been given to the field of fine diamond crystal growth and a principle is presented for the optimum P-T conditions for fine diamond synthesis.  相似文献   

7.
本文记述了一件采自辽西北票四合屯义县组下部东方翼龙的新标本。通过与正型标本的比较,证明东方翼龙为一有效的属,隶属于梳颌翼龙科。根据对新标本的研究,东方翼龙的修订特征应为:两翼展宽不超过1.25m,尺骨与飞行指的第二指节及胫骨几乎等长,第三足庶骨与胫骨长度之比约为0.40。论杨氏东方翼龙在翼手龙类的系统位置@吕君昌$中国地质科学院地质研究所!北京,100037 @高春玲$大连自然博物馆!116023 @孟庆金$大连自然博物馆!116023 @刘金远$大连自然博物馆!116023 @季强$中国地质科学院地质研究所!北京,100037…  相似文献   

8.
Pterosaur skulls were shaped by a host of selective pressures and because of the great number of variables they present a dizzying array of morphologies. These permutations present functional suites that can be analyzed allowing for a greater appreciation of pterosaur paleobiology.  相似文献   

9.
The Zarshuran arsenic deposit has been exploited for more than one thousand years. During this period of time, trace element pollutants have been transported downstream via natural agents, however this process has been exacerbated by human interferences, …  相似文献   

10.
Glass and gas inclusions have been observed in olivine and other minerals in 30 doubly polished tin sections of Jilin meteorites, indicating that there must have been melting And condensation stages during the process of meteorite formation. Temperatures of formation have been determined by homogenization and quenching runs,giving 1050-200℃ and 502℃ for glass and gas inclusions respectively, Meanwhile,the fibrous radial crystals of pyroxene have been notieed to grow when heated over 800℃. These observations are in general agreement with the available experimental data and theoretical calculations regarding meteorite.  相似文献   

11.
近年来国家对钛的需求越来越大,从钛铁矿中选钛成为急需解决的的问题。莒县天宝钛铁矿通过重磁联合选矿方法从尾矿中选钛,有效地回收了钛资源,增加了产品品种,拉长了产业链,实现了资源的综合利用,减少了污染和土地占用,保护了环境。  相似文献   

12.
Fundamental data on the residual saturation of incompressible filter cakes which have been drained by vacuum have been measured. The effects of varying particle size, shape and distribution, type of wetting fluid and cake size have been assessed. A modified ‘threshold pressure’, below which dewatering will not occur, has been defined and an index reflecting the nature of the particles and their packing has been used to represent reduced saturation data. Irreducible saturation levels have been correlated against a capillary number, and by careful definition of the driving force term data scatter have been substantially reduced.  相似文献   

13.
刘树亮 《山东地质》2011,(12):46-49
潍坊市坚持以科学发展观为指导,不断加强矿产资源执法监管力度,严格治理整顿矿产资源开发秩序,强化地质勘查和保护治理,科学调整矿业结构,优化开发布局,全面提高矿产资源综合利用水平,取得了较好的社会效益、经济效益和生态效益。  相似文献   

14.
兴隆庄煤矿近井网和井筒十字中线破坏严重,为了保障煤矿正常的生产需求,利用GPS技术建立了D级GPS近井网,利用三等水准测量确定了近井网各GPS点的正常高程,并利用高精度全站仪恢复了井筒十字中线,进行了垂直度检测,埋设了基桩点。  相似文献   

15.
莒县积极探索农村宅基地登记发证工作方式,通过简化确权表格,做好变更、注销登记等工作,提高了工作效率和质量,进一步明晰了农村土地产权,维护了农民和农村集体经济组织的合法权益,促进了社会和谐和新农村建设的顺利开展。  相似文献   

16.
Most deposited sands exhibit anisotropic behaviour. A plasticity model has been proposed with the capacity for simulating such anisotropic behaviour. The proposed model contains a number of coefficients of anisotropy. Methodology for determination of the coefficients of anisotropy has been discussed. Using experimental data, the coefficients of anisotropy have been determined for a number of well-known sands. Stress-dilatancy has been modelled by using the ‘normalized work’ and it has been shown that the normalized work is independent of inherent anisotropy. Finally, some reasonably close comparisons between experimental results and model simulations have been reported.  相似文献   

17.
The present article reports studies to develop a univariate model to forecast the summer monsoon (June–August) rainfall over India. Based on the data pertaining to the period 1871–1999, the trend and stationarity within the time series have been investigated. After revealing the randomness and non-stationarity within the time series, the autoregressive integrated moving average (ARIMA) models have been attempted and the ARIMA(0,1,1) has been identified as a suitable representative model. Consequently, an autoregressive neural network (ARNN) model has been attempted and the neural network has been trained as a multilayer perceptron with the extensive variable selection procedure. Sigmoid non-linearity has been used while training the network. Finally, a three-three-one architecture of the ARNN model has been obtained and after thorough statistical analysis the supremacy of ARNN has been established over ARIMA(0,1,1). The usefulness of ARIMA(0,1,1) has also been described.  相似文献   

18.
Choosing a municipal landfill site by analytic network process   总被引:2,自引:1,他引:2  
In this study, analytic network process (ANP), one of the multi-criteria decision making (MCDM) tools has been used to choose one of the four alternative landfill sites for the city of Eskisehir, Turkey. For this purpose, Super Decision Software has been used and benefit opportunity cost and risk (BOCR) analysis has been done to apply ANP. In BOCR analysis, each alternative site has been evaluated in terms of its benefits, costs and risks; the opportunity cluster has been examined under the benefit cluster. In this context, technical, economical and social assessments have been done for the site selection of sanitary landfill. Also, results have been compared with analytic hierarchy process (AHP) which is another MCDM technique used in the study conducted before. Finally, the current site has been determined as the most appropriate site in both methods. These methods have not been commonly used in the discipline of environmental engineering but it is believed to be an important contribution for decision makers.  相似文献   

19.

Aspects of riverbed evolution including bank erosion in the Ural River basin have been considered in this paper. The natural morphodynamic types of riverbeds have been described. The spatial features of their genesis have been characterized within the Ural River basin. To study the riverbed processes, decoding of remote sensing data of the water surface has been used. The risks for the infrastructure facilities and for the residential districts have been analyzed in terms of the bank erosion in the Ural River basin. The issues concerning the border between the Russian Federation and the Republic of Kazakhstan due to riverbed reconfiguration of the Ural River have been outlined. Maps of the development of bank erosion in the Ural River basin have been created. A way to solve the problem of riverbed evolution along the border area has been proposed by organizing an Intergovernmental Specially Protected Natural Zone.

  相似文献   

20.
Fields of the Planck cosmic-microwave background maps in the regions of radio sources of the RCR catalog have been studied. Using measurements from the Planck catalog, calibration curves have been plotted in order to determine the objects’ luminosities. The flux densities at millimeter and submillimeter wavelengths of 83 objects with normal radio spectra have been estimated for the first time; their spectra have also been constructed, they have been optically identified, and information available in various databases has been collected. A statistical comparison with a sample of sources with steep radio spectra has been carried out. Faint, difficult to characterize microwave sources make an additional contribution to the secondary anisotropy on angular scales < 7′. An algorithm for selecting candidate objects with the Sunyaev–Zel’dovich effect has been proposed, based on the use of data on the radio spectral indices and the signal in cosmic-microwave background maps.  相似文献   

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