EXPERIMENTS ON FLOW AROUND A CYLINDER IN A SCOURED CRANNEL BED     

I. ISTIARTO  W.H. GRAF Res. Asst.  Lab. de recherches hydrauliques  Ecole Polytechnique Federale  Lausanne  Switzerland. E-mail: adhy.kurniawan@epfl.ch or istiarto@tsipil.ugm.ac.id Prof  Lab. de recherches hydrauliques  Ecole Polytechnique Federal 《国际泥沙研究》2001,(4)

1 INTRODUCTION'LOcal scour around a pier is a result of the interatiOn amongst the pier, the aPproach flow and theerodible bed. The Presence of a pier results in a stagnation pressure build-up in front of the pier and athree-dimensional tUrbulent flow echaracterized by the downward flow ahead of the pier and the so-called horseshoe vortex along the base of the Pier forms itself The flow modifies the erothe bed inthe vicinity of the pier when local scour takes place (Graf and AJhnakar l…  相似文献   

LABORATORY PROFILE THE LABORATORY FOR ANALYTICAL CHEMISTRY,UNIVERSITY OF NIJMEGEN,NIJMEGEN,THE NETHERLANDS     

HEAD OF THE LABORATORY:GERRIT KATEMAN 《地理学报(英文版)》1993,(2)

The city of Nijmegen is situated in the East of the Netherlands,close to where the river Rhineenters the country from Germany.It was already known as a strategic point of interest duringthe days of the Roman Empire.Nijmegen has always belonged to the Dutch part of theNetherlands,meaning that it never was occupied by Spain (as the South was).The identity ofa strategically important,fortified and walled city has long dominated Nijmegen and thisreputation remained even up to the second world war.For about a century,Nijmegen has been  相似文献   

Structural pattern of eastern Himalayan syntaxis in Namjagbarwa and its formation process   总被引：20，自引：4，他引：16  

ZHANG Jinjiang  Jl Jianqing  ZHONG Dalai  DING Lin & HE Shundong. Department of Geology  Peking University  Beijing  China  . Institute of Geology  Geophysics  Chinese Academy of Sciences  Beijing  China Correspondence should be addressed to Zhang Jinjiang 《中国科学D辑(英文版)》2004,47(2):138-150

The structural pattern of the eastern Himalayan syntaxis in Namjagbarwa consists of two series of structures with different styles. One series compiles the earlier ductile contrac-tional and lateral-slip deformation system, formed by nearly north-south shortening within the syntaxis, left-lateral and right-lateral slipping along its western and eastern boundaries respectively. They were possibly produced by the indentation of the Indian continent into Asian continent after India-Asia collision. The peak deformation-metamorphic ages in these structures are 62-60 Ma, -23 Ma and -13 Ma. The other series is composed of ductile-brittle normal faults distributing concentrically and dipping toward the outsides of Namjagbarwa Peak. They were probably the collapse structures caused by rapid uplift in a later time and the beginning ages for the normal faulting are about 7.3-6.3 Ma.  相似文献   

Typical basin-fill sequences and basin migration in Yanshan, North China ——Response to Mesozoic tectonic transition   总被引：6，自引：0，他引：6  

LI Zhong  LIU Shaofeng  ZHANG Jinfang & WANG Qingchen. Institute of Geology  Geophysics  Chinese Academy of Sciences  Beijing  China  . China University of Geosciences  Beijing  ChinaCorrespondence should be addressed to Li Zhong 《中国科学D辑(英文版)》2004,(2)

Basin-fill sequences of Mesozoic typical basins in the Yanshan area, North China may be divided into four phases, reflecting lithosphere tectonic evolution from flexure (T3), flexure with weak rifting (J1+2), tectonic transition (J3), and rifting (K). Except the first phase, the other three phases all start with lava and volcaniclastic rocks, and end with thick coarse clastic rocks and/or conglomerates, showing cyclic basin development rather than simple cyclic rift mechanism and disciplinary basin-stress change from extension to compression in each phase. Prototype basin analysis, based on basin-fill sequences, paleocurrent distribution and depositional systems, shows that single basin-strike and structural-line direction controlling basin development had evidently changed from east-west to northeast in Late Jurassic in the Yanshan area, although basin group still occurred in east-west zonal distribution. Till Early Cretaceous, main structural-line strike controlling basins just turned to northeast by  相似文献   

Detection of spheriodal free oscillation excited by Peru 8.2 M_s earthquake with five international superconducting gravimeter data     

LEI Xiang''''e  XU Houze & SUN Heping Key Laboratory of Dynamic Geodesy  Institute of Geodesy  Geophysics. Chinese Academy of Sciences  Wuhan  China Correspondence should be addressed to Lei Xiang''''e 《中国科学D辑(英文版)》2005,48(1)

In this paper, authors obtain the spectral peaks of the earth free oscillation and check all normal modes from 0S0 to 0S48 accurately, with the Fourier analysis and the maximum entropy spectrum method dealing jointly with six groups of the observational residual data from five international superconducting gravimeter stations. By comparing the observational results in this paper with three former groups of observations or models, authors notice an extra discrepancy between two observational 0S2 modes excited separately by Peru earthquake and Alaska earthquake, which probably mirrors the anisotropy of the Earth's inner core. The analysis on the splitting 1S2 mode shows that the asymmetric factor of rotationwise spectral splitting is possible to be different from that of anti-rotationwise spectral splitting.  相似文献