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111.
Production and expenditure rates in the terrestrial budget of various air properties (mass of precipitable water and carbon dioxide, zonal and root mean square momentum, heat, and entropy) are studied. The discussion is based on graphs and diagrams which illustrate the global radiation and heat budget, dynamical energy forms and conversions, hydrologic and carbon dioxide cycles, and meridional cross sections of mass, momentum, heat, and entropy budget terms. A comparison of atmospheric property holdings with expenditure rates results in a fictitious interval of time required to annull the holdings. For momentum, precipitable water, and heat this interval of time has the order of magnitude of 100, 101, and 102 days, respectively.
Zusammenfassung Es werden die Einnahme- und Ausgabeposten beim terrestrischen Haushalt verschiedener Eigenschaften der Luft (Wasserdampf und Kohlensäure als Beispiele von Masseneigenschaften, ferner zonal-vektorieller und skalarer Impuls, Wärme und Entropie) untersucht. Die Diskussion wird durch graphische Darstellungen und Diagramme unterstützt, welche folgende Größen veranschaulichen: den globalen Strahlungs- und Wärmehaushalt, dynamische Energieformen und ihre Umwandlungen, Wasserkreislauf und Kohlensäurekreislauf, sowie Bilanzposten der Massen-, Impuls-, Wärme- und Entropiebilanz in Meridionalschnitten. Eine Vergleichung des Gehalts der Atmosphäre an verschiedenen Eigenschaften mit ihren Verlusten liefert ein fiktives Zeitintervall, in welchem die Reserven aufgebraucht würden, wenn kein Ersatz nachgeliefert würde; die Größenordnung dieses Zeitintervalles ergibt sich zu 100, 101 und 102 Tagen für Impuls, Wasserdampf und Wärme.

Résumé L'auteur étudie la production et la dépense dans le bilan terrestre des différentes propriétés de l'air (la vapeur d'eau et le dioxyde de carbone comme exemples de propriétés de masse, puis la quantité de mouvement zonale-vectorielle et scalaire, la chaleur et l'entropie). Des graphiques illustrent la discussion qui représentent les grandeurs suivantes: économie globale de la radiation et de la chaleur, formes dynamiques de l'énergie et leurs transformations, cycles hydrologique et du dioxyde de carbone, ainsi que les composantes du bilan des masses, de la quantité de mouvement, de la chaleur et de l'entropie en coupes méridionales. La comparaison du contenu des diverses propriétés dans l'atmosphère avec leurs pertes est fournie par un intervalle de temps fictif, pendant lequel les réserves seraient épuisées, au cas où leur renouvellement ferait défaut; l'ordre de grandeur de cet intervalle résulte à 100, 101 et 102 jours respectivement pour la quantité de mouvement, la vapeur d'eau et la chaleur.


With 8 Figures.  相似文献   
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Results of seven dye tracing tests done from 1993–1997 to investigate the extent to which lakes and surface water interact with the underlying Triassic Piora Aquifer, Switzerland, are reported here. Two of the dye tracing tests showed that groundwater flows in the Piora Aquifer from the Piora Valley to springs in the adjacent Santa Maria Valley, and even further east to the di Campo Valley considerably outside of the Piora Valley surface water divide. Lake Ritom located in the Piora Valley loses water only to the Canaria Valley outside of the lake's surface-water watershed at the lake's western margin when lake levels are above 1,835 m above sea level. Dye tracing tests show that a major sinkhole in the Piora Valley, Calderoni Sinkhole, is located precisely on the water divide where subsurface flow in the Piora Valley and surface water diverge and move in opposite directions. The dye tracing results also showed no hydraulic connection between surface water in the Piora Valley and the famous Pertusio Spring, located in the upper Santa Maria Valley. Only a small amount of dye from the two dye tracing tests done in 1993 and 1997 entered an exploratory gallery built to test the viability of the AlpTransit tunnel, being built in competent rock under the Triassic Piora Aquifer, effectively perched above. Electronic Publication  相似文献   
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The ramifications of a particular type of causality constraint, namely so-called shadow-zones, are explored in the context of time-dependent boundary element methods. In particular, wave propagation problems in 2-D elastic soil media with a non-convex shape are analysed.  相似文献   
117.
From 1979 to 1984, the overall water balance of the Dead Sea was characterized by a water deficit. However, an excess of freshwater inflow during the 1979/80 rainy season resulted in a 3-year-long meromictic phase. This was followed by three consecutive overturns of the water column in December 1982, 1983 and 1984. The buildup and dissipation of the seasonal thermocline and halocline is followed throughout this period which covers a wide range of water balance situations. The gravitational stabilities of the summer pycnoclines, measured in terms of N2 3×10−2 s−2, are at least one order of magnitude greater than the values reported in freshwater lakes and oceans. The contributions of temperature and salinity to N2 and to the integrated stability W are examined separately, and their interdependence is pointed out. Two irreversible effects in the evolution of the properties of the water masses are identified: (1) a monotonic increase in the density of the deep waters; and (2) a monotonic shift of the NaCl saturation curve towards higher salinities.  相似文献   
118.
The Sun's limb darkening was observed repeatedly between the 1986 minimum and the 1990 maximum of solar activity.Systematic variations, which could depend either on the momentary activity and/or the phase in the solar cycle, werenot detectable, either at continuum wavelengths or in two broad-band spectral intervals. Completelyirregular variations, which concern not only individual, successive scans (due to granulation, etc.), but also thedaily andseasonal averages, are usually less than 1%, but can reach occasionally 2% or even more. Minoreast-west asymmetries even in the seasonal means seem to be well established, mainly for < 400 nm. Thefinal, mean limb-darkening coefficients agree basically with those published by Pierce and Slaughter (1977) and Pierce, Slaughter, and Weinberger (1977), but show a much lower scatter when plotted against wavelength.  相似文献   
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Wang  Fei  Konietzky  Heinz  Frühwirt  Thomas  Dai  Yajie 《Acta Geotechnica》2020,15(8):2259-2275

The knowledge about thermo-mechanical properties of granite is still limited to some extent. Individual measurements are necessary to obtain reliable properties for specific granite types. A reliable numerical model of thermal cracking behaviours of granite exposed to extreme high temperatures (e.g. 800–1000 °C) is missing. In this study, the impact of temperature up to 1000 °C on physical, mechanical, and thermal properties as well as thermo-mechanical coupled behaviour of Eibenstock granite was investigated by laboratory testing and numerical simulations. The physical properties including mineral composition, density, P-wave velocity, and open porosity are measured to be temperature dependent. Uniaxial compression and Brazilian tests were carried out to measure uniaxial compressive strength (UCS), Young’s modulus, stress–strain relationship, and tensile strength of Eibenstock granite before and after thermal treatment, respectively. Thermal properties including specific heat, thermal conductivity, thermal diffusivity, and linear thermal expansion coefficient are also measured and found to be temperature dependent, especially the expansion coefficient which shows a steep increase around 573 °C as well as at 870 °C. The numerical simulation code FLAC3D was used to develop a numerical scheme to simulate the thermal-induced damage of granite at high temperatures. Statistical methods combined with real mineral composition were used to characterize the heterogeneity of granite. The numerical model is featured with reliable temperature-dependent parameters obtained from laboratory tests. It can well reproduce the laboratory results in form of thermal-induced micro- and macrocracks, as well as the stress–strain behaviour and the final failure pattern of Eibenstock granite after elevated temperatures up to 1000 °C. The simulation results also reveal that the thermal-induced microcracks are randomly distributed across the whole sample. Although most thermal-induced damages are tensile failures, shear failure begins to develop quickly after 500 °C. The obvious UCS reduction in granite due to heating is mainly caused by the increase in shear failure. The simulation also shows that the dominant impact of αβ quartz transition is widening pre-existing cracks rather than the formation of new microcracks.

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