Discussion on a paper by J. L. Beck and M. J. Dowling     

V. W. Lee  J. L. Beck  M. J. Dowling 《地震工程与结构动力学》1988,16(8):1227-1231

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Energy market failure in road transport: Is there scope for ‘no regrets’ greenhouse gas reduction?     

Barry Naughten  Bruce Bowen  Tony Beck 《Climatic change》1993,25(3-4):271-288

The Australian Government policy on reduction of greenhouse gas emissions announced in 1990 includes exploring the scope for immediate, low cost reductions. Such measures can be taken as including ‘no regrets’ policies: those that, in addition to mitigating potential climate change, confer economic gains (including other environmental benefits) which exceed their costs. Some possible ‘no regrets’ opportunities and policies are identified relevant to energy use by the road transport sector over the period to 2020. The MARKALMENSA multi-period linear programming model of the Australian energy sector is used to investigate the cost-effectiveness of these policies.  相似文献   

Continuous measurements of hydrographic and hydrochemical parameters in surface waters of the Baltic Sea and the North Sea in march and april 1991     

Dr. Christoph Osterroht 《Ocean Dynamics》1994,46(2):115-130

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Preface     

A.E. Beck 《Tectonophysics》1985,121(1):VII-IX

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Palaeozoic flysch series in the Coastal Cordillera of Northern Chile     

Dr. Christoph Breitkreuz  Heinrich Bahlburg Dipl.-Geol. 《International Journal of Earth Sciences》1985,74(3):565-572

A discontinuous outcrop of Palaeozoic rhythmic clastites appears in the North Chilean Coastal Cordillera. The Formación El Toco (21°15–22°15S) whose scarce flora points to a presumably Upper Devonian age forms the northernmost part of the outcrop. It is discordantly overlain by Lower Jurassic volcanics (Fm. La Negra), its base, however, is not exposed. Hercynian heteromorphous deformation led to predominantly NW trending folds strongly inclined mostly to the SW. Chevron-like folds of 0.1 to 30 m occur locally and seem to display properties transitional between synsedimentary-gravitational and early tectonic deformation.The series which is at least 2300 m thick consists of proximal, in parts pebbly turbidites with non-turbiditic finegrained intercalations. Incomplete BOUMA-sequences frequently begin with A-beds of grey to green immature, badly sorted coarse sandstones of up to 6 m thickness containing isolated quartz- and pelite-clasts.Measurements of flute casts and f oresets show palaeocurrents which came from NW and NNE. Along with petrographic observations they indicate southward directed transport of detritus from low metamorphic sedimentary and magmatic source areas into an Upper Devonian nonvolcanic basin.

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Zusammenfassung Die Formación El Toco ist der nördlichste Aufschluß einer Kette von Vorkommen paläozoischer rhythmischer Klastite in der nordchilenischen Küstenkordillere. Diese Formation (21°15–22°15S), deren spärliche Flora vorbehaltlich dem Oberdevon zuzuordnen ist, wird diskordant von unterjurassischen Vulkaniten (Fm. La Negra) überlagert —das Liegende ist nicht aufgeschlossen. Variszische heteromorphe Deformation führte zu vorherrschend NW-streichender Faltung, die meist starke SW-Vergenz zeigt. Lokal tritt eine scharfe Verfaltung im 0,1 bis 30 m-Bereich hinzu, die sowohl synsedimentär-gravitative als auch frühtektonische Deformationsmerkmale zeigt.Die mindestens 2300 m mächtige Serie ist ein proximaler Flysch mit z. T. kiesführenden Turbiditen, in die nichtturbiditische feinkörnige Partien eingeschaltet sind. Die unvollständigen BOUMA-Sequenzen beginnen häufig mit einer aus grauen bis grünen unreifen und schlechtsortierten Grobsandsteinen bestehenden A-Division von bis zu 6 m Mächtigkeit, die isolierte Quarz- und Pelitklasten enthalten kann.Flute cast- und Foreset-Messungen weisen auf Paläoströmungsrichtungen aus NW und NNO hin. Zusammen mit petrographischen Analysen läßt sich daraus ein südwärts gerichteter Transport von schwachmetamorphsedimentärem und magmatischem Detritus in ein oberdevonisches nicht-vulkanisches Becken ableiten.

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Résumén Ritmitas clásticas de edad paleozoica forman afloramientos discontinuos en la Cordillera de la Costa del Norte de Chile. La Formación El Toco (21°15–22°15S), que contiene una flora escasa de probable edad Devónico Superior, constituye la parte más septentrional de estos afloramientos. La base no se conoce, mientras que el techo infrayace discordantemente a volcanitas jurásicas inferiores (Fm. La Negra). Deformaciones hercínicas heteromórficas llevan a la formación de pliegues orientados predominantemente al NW inclinados fuertemente al SW. Localmente aparecen pliegues en forma de chevron de un tamano de 0.1 a 30 m que muestran caracteristicas de deformación transicional entre sinsedimentana-gravitativa y tectónica temprana.La serie que tiene una potencia de por lo menos 2300 m consiste en turbiditas proximales parcialmente con gravas e intercalaciones finas no-turbidíticas. Secuencias incompletas de BOUMA empiezan frecuentemente con capas de la division A (espesor maximo 6 m) los cuales se componen con frecuencia de areniscas gruesas gris-verdes, composicionalmente inmaduras y mal seleccionadas, con clastos aislados de cuarzo y pelita.Medidas de flute casts y foresets muestran paleocorrientes provenientes de NW y NNE. Junto con observaciones petrográficas, las paleocorrientes indican un transporte de material detrítico, originado de áreas con rocas sedimentarias, metamórficas de bajo grado e ígneas, dirigido al sur hacia una cuenca no volcánica de edad Devónico Superior.

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- , - . (21°15 - 22°15 ) , ; - ( -). . , . . NW , SW. 0,1 30 , , - , - . 2300 , . , . , NW a NNE. , , .

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Eliminierung und Rückgewinnung von Metallionen aus Abwässern — eine Übersicht     

R. Kümmel  F. Winkler  R. Beck 《洁净——土壤、空气、水》1984,12(3):227-237

The present state and the trends of the recovery of heavy metals from wastewaters are presented. The classical precipitation techniques are insatisfactory due to increases of solubility in the presence of impurity ions and/or complexing agents. At present, ion-exchange processes constitute the most frequently used method of metal recycling with an effective enrichment of metal ions. For the effective separation of metals from solutions of a low concentration the electrolytic reduction demands large electrode surface areas. In cells with fixed-bed or fluidized cathodes one can obtain specific electrode surface areas of some 10³ m²/m^m3. For the future, processes of extraction and especially membrane separation will gain in importance. In the past few years, a large number of highly selective metal extracting agents as well as the liquid membrane permeation with suitable carriers were developed. Combinations of membrane separation processes with chemical reactions may attain the same importance, as e.g. ultrafiltration in connection with the fixation of metal ions to watersoluble polymers. In the long run, especially techniques will prevail which will not only result in metal enrichment but also in the recovery of the raw material water.  相似文献   

Atmospheric effects from post-nuclear fires     

Paul J. Crutzen  Ian E. Galbally  Christoph Brühl 《Climatic change》1984,6(4):323-364

During a large nuclear war, the atmosphere would be loaded with huge quantities of pollutants, which are produced by fires in urban and industrial centers, cultivated lands, forests and grasslands. Especially detrimental are the effects of light absorbing airborne particles. An analysis of the amounts of the various types of fuels which could burn in a nuclear war indicates that more than 10¹⁴ g of black smoke could be produced by fires started by the nuclear explosions. Due to this, the penetration of sunlight to the earth's surface would be reduced greatly over extended areas of the northern hemisphere, maybe even globally. This could temporarily cause extreme darkness in large areas in midlatitudes and reduce crop growth and biospheric productivity.This situation would last for several weeks and cause very anomalous meteorological conditions. Much solar radiation would be absorbed in the atmosphere instead of at the earth's surface. The land areas and lower atmosphere would, therefore, cool and the overlying atmosphere warm, creating strong vertical thermal stability in a highly polluted atmosphere. For extended periods and in large parts of the world, weather conditions would be abnormal. The resulting cold, probably freezing, temperatures at the ground would interfere severely with crop production during the growing season and cause extreme conditions for large sections of the biosphere. The combination of lack of sunlight, frost and other adverse meteorological conditions would add enormously to the already huge problems of the survivors.  相似文献   

Further Studies Of Atmospheric Turbulence In Layers Near The Surface: Scaling The Tke Budget Above The Roughness Sublayer   总被引：2，自引：0，他引：2  

Paul Frenzen  Christoph A. Vogel 《Boundary-Layer Meteorology》2001,99(2):173-206

The second of two experimental studies of the TKE budget conducted on sites of different roughness is described, and results are compared. The first took place within a shallow layer above a small field of mostly bare, cultivated soil; the second was carried out above a roughness sublayer of significant depth on an extensive plain of tall dry grass. Budget terms observed in the second study were scaled with a modified u which compensated for effects of an unusually large stress gradient and ensured that the _m functions would be collinear. By showing that the modification becomes negligible in smaller gradients, it is demonstrated that in normal conditions, budgets observed above significant roughness sublayers should be normalized by scaling in terms of the unreduced Reynolds stress at the sublayer's upper surface. This procedure is shown to be consistent with the expectation that TKE budgets in layers near the surface all scale in fundamentally the same way.Other findings include: (1) the fact that most _m functions previously reported are not quite collinear is attributed to a type of overspeeding known to affect three-cup anemometers; (2) revised _m functions, collinear and largely free of the effects of overspeeding, are determined from a well-established characteristic of the linear _m relation for the stable case; (3) data that define collinear _m functions can also be represented with single hyperbolic curves; (4) dissipation is found to be 10 to 15% too small to balance total TKE production in unstable and neutral conditions and to decrease with increasing z/L in thestable regime; and (5) new relations for based on the observed behaviour of the dissipation deficit provide an improved closure for the set of equations that express the budget terms as functions of _m and z/L.  相似文献   

Parameterisation of the vertical transport in a small thermally stratified lake     

Christoph von Rohden  Karl Wunderle  Johann Ilmberger 《Aquatic Sciences - Research Across Boundaries》2007,69(1):129-137

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Conceptual examination of climate–soil controls upon rainfall partitioning in an open-fractured soil II: Response to a population of storms     

Iain Struthers  Christoph Hinz  Murugesu Sivapalan 《Advances in water resources》2007

A simple two-domain bucket model of fractured soil was coupled with a stochastic model of rainfall variability, in order to investigate the climate and soil controls upon the stochastic properties of the triggering of fracture flow and surface runoff, and the partitioning of rainfall between the matrix and fracture domains and surface runoff. Conventionally, soils are regarded as time domain filters between rainfall and hydrological response. This investigation highlights an additional type of threshold filtering especially important in understanding the infiltration behaviour of fractured soils, for which an event-based characterisation of rainfall in modelling is crucial. A priori-definable indices were derived which are capable of describing elements of this threshold filtering, by allowing the statistical properties of fracture flow- and surface runoff-triggering storms (i.e., mean and variance of storm duration, intensity and effective inter-storm period, as well as cumulative partitioning of rainfall), to be inferred directly from average storm and soil properties. Using these indices, the long-term response of fractured soils, including the long-term hydrological importance of fractures, can be estimated without simulation.  相似文献