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11.
Norbert I. K 《冰川冻土》2004,26(Z1):310-318
The exploration of ice sheets by melting vertical holes into the ground has some tradition in terrestrial glaciology. Such probes have been used since the 1960's to investigate the vertical structure of the ice in Greenland and Antarctica and in alpine glaciers. In this paper we look into the possibility to develop similar devices for use on extraterrestrial icy bodies, like e.g. the polar areas on Mars or the icy satellites of the outer solar system. We report on some basic experiments performed in the cryo-vacuum laboratory of the Space Research Institute of the Austrian Academy of Sciences, Graz. In these experiments the penetration of a simple melting probe into compact and porous water ice (with a snow-like texture) was monitored, both under vacuum conditions and under air pressure. The observed penetration speeds for a given power supply are compared with a simple mathematical model. We conclude that a miniature melting probe with small overall dimensions and a reasonable power demand could well be part of the payload of a future planetary mission, for example to the poles of Mars. Such missions are currently under discussion in several space agencies. Moreover such probes could also e? ectively be used in terrestrial environments. A possible design is presented at the end of the paper. 相似文献
12.
YAN Shouxun Laboratory of Remote Sensing Information Sciences Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing China 《中国科学D辑(英文版)》2004,47(9)
To examine the application potential of hyperspectral remote sensing techniques in classifying very low-grade metamorphic belts, the composition of clay minerals and the cyrstallinity of illite from mudstones were measured using XRD and VIS-SWIR (400-2500 nm) reflectance spectroscopy. Based on the illite cyrstallinity, Kubler Index (KI), the Early Triassic LuoLou Group and the Middle Triassic lower Baifeng Formation were classified as the lower Epizone with KI△2θ° ranging from 0.22 to 0.25, the upper Baifeng Formation as upper anchizone with KI△2θ°ranging from 0.26 to 0.33, and the Hekou Formation as lower anchizone with KI△2θ° ranging from 0.38 to 0.40. According to a KI△2θ° value of 0.43, it is possible that there may exist a local diagenetic zone in the upper strata. The illite cyrstallinity Kubler index and the metamorphic grade increase from the bottom to the top of the stratigraphic sequence. The metamorphic grade boundaries nearly match the stratigraphic boundaries, indicating a burial metamorphism nature for the stratigraphic sequence. From the bottom to the top of the sequence, the spectral absorption band center of clay minerals from fresh rocks is around 2200 nm. The absorption band centers change towards shorter wavelengths: the Luolou Group being at 2220 nm, the Baifeng Formation at 2217-2213 nm, the lower member of the Hekou Formation at 2214-2206 nm, and the upper member of the Hekou Formation at 2205-2197 nm. The spectral absorption band center of illite shows the same change pattern. These results indicate that very low-grade metamorphic belts can be subdivided using spectral indices of clay minerals, which are measured by using field portable spectroradiometers. However, it may not work well with satellite and airborne sensors. 相似文献
13.
KANG Shi chang QIN Da he YAO Tan dong PAUL A. Mayewski SALLIE Whitlow 《中国地理科学(英文版)》2000,10(3):218-225
Investigations of atmospheric composition in the Himalayas has been limited in both temporal and spatial scales, mainly due to difficult logistics. Ideal sites for monitoring atmospheric composition and its evolution should be free from local pollution and representative of the remote troposphere (HUEBERT et al., 1980). As the Himalayas are far removed from highly industrialized regions they provide suitable locations to monitor the chemistry of the remote troposphere and to study the evolu… 相似文献
14.
Geochemical Features of Ophiolite in Mianxian Lueyang Suture Zone,Qinling Orogenic Belt 总被引:10,自引:0,他引:10
GeochemicalFeaturesofOphioliteinMianxianLueyangSutureZone,QinlingOrogenicBeltLaiShaocong;ZhangGuowei(DepartmentofGeology,Nort... 相似文献
16.
新疆塔里木盆地西部晚白垩世—早第三纪的沟鞭藻及疑源类 总被引:3,自引:0,他引:3
一、前言 新疆塔里木盆地西缘上白垩统一下第三系含有丰富的沟鞭藻及疑源类,此外多种无脊椎动物化石也很丰富。余静贤和张望平已对该区晚白垩世的沟鞭藻和疑源类作过初步研究。郝诒纯和曾学鲁等则对该区晚白垩世—早第三纪的有孔虫作了详细的研究。 相似文献
17.
IntroductionEothrocytesedimentahonrateusSR)isanimportantindexofhemorheology.Atpresent,itisdifficulttoachieveaccuracyandcomparabilityinclinicalprachceandresearchbecauseoflackofaunifiedstandardofthereferencevalue(Wintrobe)ofhealthyPeople'sESRinChina.ManyresearchershavemeaSUredthelocalreferencevaluesofESR(Wintrobe)l'-:'l.Bymeansofcorrelationandregressionanalysis,researchontherelationshipbetweenthereferencevalue(Wintrobe)ofESRandgeographicalfactorsshowedthathlereareceylonregularPatternsbet… 相似文献
18.
CHEN Jisheng 《国际泥沙研究》1996,(2)
HYDROPOWERRESOURCESINUPPERYANGTZECHENJisheng(DirectorEmeritus,YangtzeRiverScientificResearchInstitute(YRSRI),23HuangpuRoad,Wu... 相似文献
19.
1INTRODUCTIONIrrigated ricefieldsarecharacterizedbylargespatialandtemporalvariationsin CH4 emissiontotheatmo-sphere.Accordingly,thereisagreatuncertaintyintheestimate ofCH4 emissionsfromricefields.GreateffortshavebeenmadetoestimatetheCH4 emissionsfromricefieldsandseveralapproacheshavebeendeveloped.TherepresentativemethodsincludetheIPCC(Inter-governmentPanelofClimateChange)region-specificemissionfactormethodandthemodelcalculationmethod.Toimprovethecalculationaccuracy,theIPCCmethodreq… 相似文献
20.
2015年是全面深化改革的关键之年,是全面推进依法治国的开局之年.国土资源部认真贯彻落实《国务院办公厅关于印发2015年政府信息公开工作要点的通知》(国办发[2015]22号,以下简称《通知》)精神,按要求对涉及我部的公开事项进行了认真梳理分解,将牵头落实事项(2项)、参与落实事项(4项)和普遍要求落实的事项(20项)纳入我部政府信息公开总体工作进行了安排部署,并明确了任务分工.一年来,我部紧紧围绕国土资源管理中心工作以及社会关切,着力推进征地、土地和矿业权出让、地质灾害预报预警,以及行政审批制度改革、以“三公”经费为重点的财政资金等重点领域信息公开,积极加强信息发布、政策解读和回应工作,不断增强政府信息公开实效,促进法治国土建设,服务经济社会发展. 相似文献