Medium and small embankment dams on permafrost: A discussion of current concepts     

Rudolf V. Zhang 《寒旱区科学》2014,6(4):0340-0347

This article discusses the current concepts of dam design and construction in permafrost regions. It is demonstrated that embankment dams often change their state from frozen to thawed and back during the operation period. It is shown that these transitions are not always attributable to observed climate warming. Where geotechnical, hydrogeological, and permafrost conditions are complicated, proper performance of embankment dams can only be provided by adhering to a selected thermal design for, as an example, a frozen state.  相似文献   

Using Optical Properties to Quantify Fringe Mangrove Inputs to the Dissolved Organic Matter (DOM) Pool in a Subtropical Estuary     

Kaelin M. Cawley  Youhei Yamashita  Nagamitsu Maie  Rudolf Jaffé 《Estuaries and Coasts》2014,37(2):399-410

Dissolved organic carbon (DOC) concentration and dissolved organic matter (DOM) optical properties were analyzed along two estuarine river transects during the wet and dry seasons to better understand DOM dynamics and quantify mangrove inputs. A tidal study was performed to assess the impacts of tidal pumping on DOM transport. DOM in the estuaries showed non-conservative mixing indicative of mangrove-derived inputs. Similarly, fluorescence data suggest that some terrestrial humic-like components showed non-conservative behavior. An Everglades freshwater-derived fluorescent component, which is associated with soil inputs from the Northern Everglades, behaved conservatively. During the dry season, a protein-like component behaved conservatively until the mid-salinity range when non-conservative behavior due to degradation and/or loss was observed. The tidal study data suggests mangrove porewater inputs to the rivers following low tide. The differences in quantity of DOM exported by the Shark and Harney Rivers imply that geomorphology and tidal hydrology may be a dominant factor controlling the amount of DOM exported from the mangrove ecotone, where up to 21 % of the DOC is mangrove-derived. Additionally, nutrient concentrations and other temporal factors may control DOM export from the mangroves, particularly for the microbially derived fluorescent components, contributing to the seasonal differences. The wet and dry season fluxes of mangrove DOM from the Shark River is estimated as 0.27?×?10⁹ mg C d^?1 and 0.075?×?10⁹ mg C d^?1, respectively, and the Harney River is estimated as 1.9?×?10⁹ mg C d^?1 and 0.20?×?10⁹ mg C d^?1.  相似文献   

MONITORING POLYNUCLEAR AROMATIC HYDROCARBONS IN SEDIMENT POREWATER BY SPMD   总被引：1，自引：0，他引：1  

朱亚先张勇  庄一廷Ka-FaiPoon MichaelH.W.Lam 洪华生 RudolfS.S.Wu 《中国海洋湖沼学报》2001,19(4):382-388

A new mimic biological Semi-permeable Membrane Device (SPMD) introduced for sampling organic pollutants yielded satisfactory results when it was frrst used as a passive sampler to concentrate and determine 16 kinds of polynuclear aromatic hydrocarbons (PAHs) by means of capillary GC on an HP 5890 GC-FID in coastal sediment perewater. The concentration of PAHs in sediment porewater for naphthalene(N), acenaphthlene(AL), acenaphthene (AE), fluorene (F), phenaphthene(P), anthracene(A), fluoranthene(FA), pyrene(Py), benzo[a]anthracene(B[a]A), chrysene(Chr), benzo[b] fluor- anthene(B[b]F), benzo[k]fluoranthene(B[k]F), benzo[a]pyrene(B[a]P),indeno[1,2,3,-cd]-Pyrene(I[123]P), dibenz[a,h]anthracene(D[ab]A) and benzo[g,h,i] perylene(B[ghi]P) were:50.36, under detection limits(UD), 18.19, 8.41, 8.40, 1.44, UD, 8.01, 524.15, 168.47, 50.13,123.66, 63.48, 27.40, 82.04 and 58,81 ng/L, respectively.  相似文献   

A normal and superoutburst study of the eclipsing SU UMa star: DV Ursae Majoris     

Daisaku Nogami  †  Taichi Kato  Hajime Baba  Rudolf Novák  J. J. Lockley  M. Somers 《Monthly notices of the Royal Astronomical Society》2001,322(1):79-84

We report on time-resolved photometry carried out during the 1995 short outburst and the 1997 long outburst in the eclipsing dwarf nova DV UMa. The revised orbital period is 0.0858526172 (67) d. We detected gigantic superhumps with an amplitude of ∼0.6 mag in the mid-phase of the 1997 outburst, revealing the SU UMa nature of DV UMa. The superhump period is 0.0887 (4) d. The superhumps became less clear during the late phase of the superoutburst, and we found two possible periods of 0.0885 (15) and 0.0764 (15). During both outbursts, the eclipse was wide and shallow near the maximum, and then became narrower and deeper, which is qualitatively well explained by the current disc instability theory.  相似文献   

Statistical Mechanics of Stable States Far from Equilibrium: Thermodynamics of Turbulent Plasmas     

Rudolf A. Treumann 《Astrophysics and Space Science》2001,277(1-2):81-95

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Deductions from the Indication of Eclipses of Nova V1493 Aql     

Michael Friedjung  Andrej Dobrotka  Alon Retter  Ladislav Hric  Rudolf Novák 《Astrophysics and Space Science》2006,304(1-4):317-319

Our mainly R band photometry of V1493 Aql (1999) during its outburst, indicates periodic variations with a period of 0.156 days, seen only 5 days after the maximum in V. This period can be orbital. The light curve indicates in addition, the presence of a faint eclipse like feature. We try to explain its extremely low amlitude, as being due to the eclipse of an expanded white dwarf component of the binary below an optically thick wind. We discuss what conditions would be required for such an interpretation to work.  相似文献   

The Sixth International Geological Congress： Zürich, 1894     

Sibylle Franks Rudolf Triimpy 《《幕》》2005,28(3):187-192

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The stability of the terrestrial planets with a more massive 'Earth'     

Áron Süli  Rudolf Dvorak  Florian Freistetter 《Monthly notices of the Royal Astronomical Society》2005,363(1):241-250

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Some effects of long-term fumigations with ozone on spruce (Picea abies [L.] Karsten)     

Theodor Keller Dr.  Rudolf Häsler Dr. 《GeoJournal》1988,17(2):277-278

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Spherically symmetric attenuation within the Earth from normal mode data   总被引：3，自引：0，他引：3  

Rudolf Widmer  Guy Masters  Freeman Gilbert 《Geophysical Journal International》1991,104(3):541-553

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