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101.
MATHEMATICAL MODELS FOR LIQUID-SOLID TWO-PHASE FLOW 总被引:2,自引:0,他引:2
Weiming Wu Sam S.Y. Wang National Center for Computational Hydroscience Engineering The University of Mississippi MS U.S.A. 《国际泥沙研究》2000,(3)
I INTRODUCTIONTurbulence models for single-phase fluid flows have been developed and widely applied in mechanical,aeronautical, environmental and hydraulic engineering, and other fields. The closure techniques for theReynolds-averaged Navier-Stokes equations for various levels of models including the simple turbulencemodel, one-equation turbulence model, k-s turbulence model and turbulence stress/flux model have beenverified to be physically reasonable and have acceptable accuracy in app… 相似文献
102.
近10余年来,特别是2000年召开第三届地层会议后,中国年代地层研究得到很快发展。首先,在全国地层委员会主持下,经各断代工作组专家们的共同努力,编制完成了《中国区域年代地层(地质年代)表》,系统建立了从震旦系至第四系中共102个阶(其中包括52个陆相地层区的阶)和新建3个系级单位。从2001年开始,在中国地质调查局的大力支持下,由全国地层委员会主持,组织全国知名地质科研院所、高校和部分地质调查院的专家,围绕中国区域年代地层表,开展了系统的建阶研究。5年来,共涉及45个阶,9个界线层型和2个新建系及2个统级单位的研究,取得重要进展。先后已有4个全球界线层型(GSSPs)被国际地质科学联合会批准建立在中国,还有3~4个全球界线层型正待国际地质学科学联合会批准建立在中国,另有3~4个界线层型剖面有望争取成为全球的界线层型。其他研究所涉及到的阶、系、统等单位,也有明显进展,成熟度明显提高,为《中国区域年代地层(地质年代)表》的广泛应用奠定了重要基础。 相似文献
103.
PENG Zicheng LEUNG Po Lau YU Peter CHENG Peikai LI Mai 《《地质学报》英文版》2006,80(5):759-762
The microprobe EDXRF equipment was used for analysis of the major and trace elements in glaze layer-transitive layer-body layer of the celadon from the Altar Yao (Kiln) and Laohudong Yao in the Southern Song Dynasty (1127-1279 A.D.), Zhejiang, China. The K values of the discriminant factor for the celadon wares are larger than 8, which means the celadon of the Altar Yao and Laohudong Yao are different from that of the Longquan Yao. The former two belong to the Guan Yao system (the Chinese imperial kilns), but the latter to the Min Yao system (the Chinese popular kilns). The principle component analysis shows their relationship between the Altar and Laohudong wares with provenance postulation. The thickness of the transitive layer in the Altar and Laohudong wares is obviously different, which reveals the microstructure characteristics of the celadon even though both kinds of wares belong to the imperial kiln system. 相似文献
104.
Ahmet Ruhi Mermut 《山地科学学报》2009,(2):I0002-I0002
Soils, the Earth's Critical Zone, play a vital and fundamental role in the Earth's terrain eco- environment system and human life. Although the concepts of soil/quality and sustainable development have been introduced for decades, we are still failing to understand how well soils function and they need tobe cared and protected. We have been increasingly witnessing and becoming the victim of shrinking forests, 相似文献
105.
1Preface Todescribeoceanicintermediatewatermasses,itis necessarytohaveawell definedstudyframeorsurfacebecauseofthefluctuationnatureofintermediatewa ters.Itiswellunderstoodthatoceanicwater mass mixingdoesnotalignwitheitheraconstantgeopoten tialdepthorapropertysurfacesuchastemperature,salinity,pressureanddensitysurfacesbutfollowsa neutraldensitysurface.Thisisbecauseawaterparcelmovesasmalldistanceisentropicallyandadiabaticallyontheneutraldensitysurfacewithoutdoingworka gainstabuoyantrestoringforc… 相似文献
106.
我国蛇绿岩分布广泛。蛇绿岩中有着成因上和时空上紧密联系的一系列非金属矿床,它们构成了蛇绿岩建造非金属矿床成矿系列。这一成矿系列中的主要非金属矿有橄榄岩、玄武岩、蛇纹岩、石棉、滑石、玉石类等等,主要的成矿作用有岩浆作用、接触变质作用、交代蚀变作用等。其成矿作用和矿床分布模式有明显规律,这些规律对于地质勘查、资源开发等都具有重要的意义。 相似文献
107.
本文分析了八家子多金属矿田的地质构造特征,提出该区的构造型式为一个滑脱—逆冲推覆构造。它是在北西问南东方向的侧向挤压作用下,由八家子附近的中上元古界与古生界地质块体,沿着与基底花岗岩的界面自北西向南东滑移造成的。主要表现特征是:在前缘形成了呈铲式的收缩型滑脱断层、逆冲断层等挤压性构造,在后缘则出现张裂带并陷落成盆地,两侧发育具有转换断层性质的走滑断层。逆冲断层及边界走精断层是区内主要控矿构造。八家子滑脱—逆冲推覆构造的主要活动时期为三叠纪晚期,结束于早侏罗世。 相似文献
108.
太阳物理学中的分形和混沌 总被引:1,自引:0,他引:1
对非线性科学的两个重要分支;分形和混沌在太阳物理学中的应用情况作了综述信要内容包括;太阳活动混沌性的揭示;对太阳活动混沌性的可能解释-太阳非线性发电机理论;一些太阳现象的分形描述;耀斑的自组织临界行为研究,最后给出了作者对这一领域工作前景的展望。 相似文献
109.
110.
D. Kesten M. Weber Ch. Haberland Ch. Janssen A. Agnon Y. Bartov I. Rabba The DESERT Group 《International Journal of Earth Sciences》2008,97(1):153-169
The left-lateral Dead Sea Transform (DST) in the Middle East is one of the largest continental strike-slip faults of the world.
The southern segment of the DST in the Arava/Araba Valley between the Dead Sea and the Red Sea, called Arava/Araba Fault (AF),
has been studied in detail in the multidisciplinary DESERT (DEad SEa Rift Transect) project. Based on these results, here,
the interpretations of multi-spectral (ASTER) satellite images and seismic reflection studies have been combined to analyse
geologic structures. Whereas satellite images reveal neotectonic activity in shallow young sediments, reflection seismic image
deep faults that are possibly inactive at present. The combination of the two methods allows putting some age constraint on
the activity of individual fault strands. Although the AF is clearly the main active fault segment of the southern DST, we
propose that it has accommodated only a limited (up to 60 km) part of the overall 105 km of sinistral plate motion since Miocene
times. There is evidence for sinistral displacement along other faults, based on geological studies, including satellite image
interpretation. Furthermore, a subsurface fault is revealed ≈4 km west of the AF on two ≈E–W running seismic reflection profiles.
Whereas these seismic data show a flower structure typical for strike-slip faults, on the satellite image this fault is not
expressed in the post-Miocene sediments, implying that it has been inactive for the last few million years. About 1 km to
the east of the AF another, now buried fault, was detected in seismic, magnetotelluric and gravity studies of DESERT. Taking
together various evidences, we suggest that at the beginning of transform motion deformation occurred in a rather wide belt,
possibly with the reactivation of older ≈N–S striking structures. Later, deformation became concentrated in the region of
today’s Arava Valley. Till ≈5 Ma ago there might have been other, now inactive fault traces in the vicinity of the present
day AF that took up lateral motion. Together with a rearrangement of plates ≈5 Ma ago, the main fault trace shifted then to
the position of today’s AF. 相似文献