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1.
The energy balance of a solid subject to fracture has been explored using heat and mass transfer equations with regard to the volumetric and superficial components. In the suggested model, brittle fracture of a cracked solid considered as a heterogeneous two-phase medium is described by an equation analogous to the Griffith’s criterion for propagation of a single crack. The derived equation is used, together with estimates of relative change in specific interface area, to study the respective change of free strain energy and pressure in rocks associated with failure. 相似文献
2.
The paper proposes a method for studying long-term anomalies of the radon concentration that are produced by an impulse generated in a fracture source over a finite time interval. Using this method, experimental data are interpreted numerically in order to determine the space-time characteristics of the fracture region and parameters of fluid migration. 相似文献
3.
N. E. Chubarova E. I. Nezval’ I. B. Belikov E. V. Gorbarenko I. D. Eremina E. Yu. Zhdanova I. A. Korneva P. I. Konstantinov M. A. Lokoshchenko A. I. Skorokhod O. A. Shilovtseva 《Russian Meteorology and Hydrology》2014,39(9):602-613
Analyzed are the results of meteorological and environmental measurements performed over the 60-year period (1954–2013) at the Meteorological Observatory of Lomonosov Moscow State University. The significant positive temperature trend (0.04°C/year for 1954–2013) was obtained; it increased up to 0.07°C/year in 1976–2012. Considered are the features of seasonal variations of different atmospheric characteristics. Discussed are the type and causes of low-frequency changes in meteorological parameters, radiation balance components, radiation in different spectral ranges, and chemical composition of precipitation. Demonstrated are possible mechanisms of the more significant increase observed in air temperature in Moscow as compared with that in Central Federal District and their connection with the greenhouse effect in the urban atmosphere. 相似文献
4.
Developed is a new mechanism of photochemical reactions taking account of the dipole interaction between the molecules and the ??sharp?? inhomogeneities of electrified ice crystals in polar stratospheric clouds. This mechanism enables to explain the ozone depression formation during the winter-spring period in the polar stratosphere. 相似文献
5.
Numerical Hydrodynamic 2D-Simulation of the Inundation of Tulun Town on the Iya R. during Flood 2019
Water Resources - Detail 3D digital elevation model with a high-accuracy efficient software for 2D-modeling STREAM 2D CUDA and actual data on high-water marks and the dynamics of water level... 相似文献
6.
Moiseenko K. B. Berezina E. V. Vasileva A. V. Shtabkin Yu. A. Skorokhod A. I. Elanskii N. F. Belikov I. B. 《Doklady Earth Sciences》2019,487(2):981-985
Doklady Earth Sciences - Estimates of the photochemical ozone generation rate, PQ, and the ozone production efficiency (OPE) per molecule of NOx (=NO + NO2), ∆P, are obtained for the region... 相似文献
7.
The mathematical model for simulating deformations of river channels composed of heterogeneous alluvium has been developed. The combination of shallow water equations and a three-layer model is used to describe the fluid flow and non-uniform sediment transport in bed (layer II) and suspended (layer III) loads. Changes in the fractional composition of unerodible bottom sediments (layer I) are also considered. The algorithm provides mass conservation for each fraction. The comparison of calculations results and experimental data (hydraulic washing of a desilting basin from sediments and armoring processes in heterogeneous soils) confirms the operability of the model. The model is applied to calculate the silting and hydraulic washes of the reservoir of a hydroelectric power station on a mountain river. 相似文献
8.
The underwater vocalizations of the beluga whale summering in Onega Bay (64°24′N, 35°49′E) were recorded in June–July of 2008.
The vocalizations were classified into five major whistle types, four types of pulsed tones, click series, and noise vocalizations.
To determine the relationship between the behavioral activity and the underwater vocalizations, a total of fifty-one 2 minute-long
samples of the audio records were analyzed in the next six behavioral contexts: directional movements, quiet swimming, resting,
social interactions, individual hunting behavior, and the exploration of hydrophones by beluga whales. The overall vocalization
rate and the percentage of the main types of signals depend on the behavior of the belugas. We suggest that one of the whistle
types (the “stereotype whistle”) is used by belugas for long-distance communications, while other whistle types (with the
exception of “squeaks”) and three types of pulsed tones (with the exception of “vowels”) are used for short distance communication.
The percentage of “squeaks” and “vowels” was equally high in all the behavioral situations. Thus, we assume that “squeaks”
are contact signals. “Vowels” have a specific physical structure and probably play a role in identification signals. A high
rate of the click series was observed in the process of social interactions. 相似文献
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10.
A. M. Zvyagintsev I. B. Belikov N. F. Elanskii I. N. Kuznetsova Ya. O. Romanyuk M. G. Sosonkin O. A. Tarasova 《Russian Meteorology and Hydrology》2010,35(12):806-812
The comparison is represented of the results of surface ozone concentration measurements in two megalopolises, Moscow and
Kiev. A temporal course of ozone concentration and temperature in both cities is close by the shape and is typical of medium-polluted
plain stations. In both megalopolises, two maxima are observed within the seasonal ozone concentration variability, in spring
and summer, and during the day, a usual ozone concentration maximum (approximately in 2–3 hours after the local noon) and
the night one being typical of big cities. An average ozone concentration and an average temperature in corresponding periods
are higher in Kiev than in Moscow. Evidently, the summer maximum is associated with photochemical ozone generation processes,
and the spring one, with dynamic processes of its transport in the atmosphere. In both megalopolises, the episodes are observed
in the warm period under meteorological conditions being unfavorable for the pollutant scattering in the atmosphere when the
ozone concentration exceeds the threshold limit value and is dangerous for health. The repeatability of such episodes is the
highest one in July-August. In Kiev, such episodes are more frequent than in Moscow. An effective statistical model is constructed
for both megalopolises in which the observed ozone concentration is represented in the form of regression function of temperature
and relative humidity. 相似文献