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A. A. Sorokin O. A. Girina E. A. Lupyan S. I. Mal’kovskii I. V. Balashov V. Yu. Efremov L. S. Kramareva S. P. Korolev I. M. Romanova E. V. Simonenko 《Russian Meteorology and Hydrology》2017,42(12):759-765
Ash clouds resulting from explosive volcanic eruptions pose a real threat to human life (for aircraft flights, airport operations, etc.); therefore, the detection, monitoring, and forecast of their movement is an urgent and important issue. The features and examples of application of the new tool developed on the basis of "Monitoring of Active Volcanoes of Kamchatka and the Kurile Islands" information system (VolSatView) are described. It allows the integrated monitoring and forecasting of ash cloud transport using the data of remote sensing and mathematical modeling as well as the assessment of the parameters of explosive events. 相似文献
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A. K. Mal 《Pure and Applied Geophysics》1962,51(1):47-58
Summary Generally Love-wave is absent in the corresponding spectrum of the phase in the low period range when the path tranversed is oceanic. ButOliver, Ewing & Press were able to observe this phase in seismograms of volcanic islands like Honolulu, Bermuda and others. Here, it has been attempted to explain why these waves could be recorded at volcanic stations and not elsewhere. It has been supposed that the lava settles down to form a transversely isotropic layer. Green's Function technique has been adopted to solve the problem of propagation of Love-waves through a crust whose thickness gradually decreases towards the ocean. 相似文献
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The pre‐calibrated and validated physically based watershed model, water erosion prediction project (WEPP) was used as a modelling tool for the identification of critical watersheds and evaluation of best management practices for a small hilly watershed (Karso) of India. The land use/cover of the study area was generated using IRS‐1C LISS‐III (linear imaging self scanner) satellite data. The watershed and sub‐watershed boundaries, drainage, slope and soil map of the study area were generated using ARC/INFO geographic information system (GIS). The WEPP model was finally applied to the Karso watershed which lies within Damodar Barakar catchment of India to identify the critical sub‐watersheds on the basis of their simulated average annual sediment yields. Priorities were fixed on the basis of ranks assigned to each critical sub‐watershed based on the susceptibility to erosion. The sub‐watershed having the highest sediment yield was assigned a priority number 1, the next highest value was assigned a priority number 2, and so on. Subsequently, the model was used for evaluating the effectiveness of best management practices (crop and tillage) for conservation of soil for all the sub‐watersheds. On the basis of this study, it is realized that cash crops like soyabean should be encouraged in the upland portion of the sub‐watersheds, and the existing tillage practice (country plough/mould board plough) may be replaced by a field cultivation system for conservation of soil and water in the sub‐watersheds. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Zusammenfassung Im Verlauf der anaeroben Fermentation des Kl?rschlammes kommt es zu ?nderungen der chemischen Eigenschaften. Die organischen
Stoffe werden in wasserl?sliche Verbindungen mit niedrigerem Molekülgewicht, diese dann weiter in Mineralkomponenten CH4, CO2, NH3 und H2S zersetzt. In der vorliegenden Arbeit sind diese ?nderungen quantitativ ausgewertet, und die Kinetik ihres Verlaufes wurde
verfolgt. Die erzielten Ergebnisse sind in Tabellen und Abbildungen zusammengefasst.
Summary The anaerobic methane fermentation of sewage sludge caused changes of its chemical properties. Organic matter is decomposed into water soluble compounds of minor molecular weight, and subjected to further decomposition into mineral components CH4, CO2, NH3 and H2S. This paper deals with these changes in a quantitative evaluation, the kinetics of their course being followed as well. The attained results are summarized into tables and graphs.相似文献
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Summary In batch fermentation tests the effect of the substrate concentration on the methane fermentation process of the sewage sludge
was controlled. In the range of 1.5 up to 6.5 percent of dry solids content in the raw sludge no changes could be demonstrated
in the fermentation course, digestion of the organic substance, sludge gas production and in the organic compounds decomposition.
The ratio of the solid phase concentration to the water content determined the ion concentration of the solution, which during
the fermentation process would increase. The ion concentration affects the enzymatic activity of the bacteria and their metabolic
process as well. The increase of the concentration of some ions, e.g. of ammonia-ions, above the given limit would inhibit
the fermentation course. At conditions of the tests this limit would not be exceeded so that the inhibition of the fermentation
could not be observed. In accordance with the composition of the mineral and organic part of the sludge particles the buffer
capacity of media would result which is considered to be most significant for preserving the pH value in suitable limits for
the bacteria, participating on the methane fermentation of organic substrate.
Zusammenfassung In Schichtfermentations-Versuchen wurde der Einfluss der Subtratkonzentration auf die Methanfermentation von Kl?rschlamm bestimmt. Es wurde nachgewiesen, dass im Bereich von 1,5 bis 6,5% Trockensubstanz keine ?nderungen im Verlaufe der Fermentation, in der Digestion organischer Stoffe, in der Faulgasproduktion und im Abbau der Kohlenstoffverbindungen auftreten. Das Konzentrationsverh?ltnis der festen Phase des Schlammes zu seinem Wassergehalt bestimmt aber die Ionenst?rke des Milieus, die w?hrend der Fermentation erh?ht wird. Die Ionenkonzentration beeinflusst die enzymatische T?tigkeit der Bakterien und dadurch auch ihre metabolischen Vorg?nge. Die Erh?hung von Ionenkonzentration (z.B. Ammoniumionen) über eine gewisse Grenze inhibiert den Fermentationsverlauf. Unter den Bedingungen der angeführten Versuche, wo die Substratkonzentration die bei dem Betrieb der Faulbeh?lter üblichen Werte nicht überschritten hat, wurde denn auch keine Inhibition der Methanfermentation beobachtet. Die Zusammensetzung des organischen und anorganischen Anteils des Schlammes bestimmt die Pufferkapazit?t des Milieus, die für die Erhaltung des pH-Wertes in den für die Bakterient?tigkeit geeigneten Grenzen wichtig ist.
Résumé L'on a, dans des essais de fermentation par couches, étudié l'effet de la concentration du substrat sur le processus de fermentation des boues d'épuration au méthane. On constata que, lorsque les boues ont une teneur en matière sèche entre 1,5 et 6,5%, il ne se produit aucun changement dans la fermentation, dans la digestion des substances organiques, dans la production de gaz de digestion, ni dans la décomposition des carbures. C'est toutefois du rapport entre la phase solide des boues et leur teneur en eau que dépend la concentration du milieu en ions, concentration qui augmente au cours de la fermentation. La concentration en ions influe sur l'activité enzymatique des bactéries et, de ce fait, aussi sur leur métabolisme. L'augmentation des concentrations de certains ions (ions d'ammonium par exemple) au-delà d'une certaine limite freine le processus de fermentation. Dans les conditions qui régnaient pendant les essais en question, les concentrations du substrat ne dépassèrent pas les valeurs observées dans la pratique, de sorte qu'il ne se produisit aucune inhibition de la fermentation au méthane. La composition de la fraction organique et celle de la fraction inorganique des boues détermine la capacité tampon du milieu, capacité qui est très importante pour le maintien de la valeur pH dans les limites favorables à l'activité bactérienne.相似文献
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L. A. Rukhovets G. P. Astrakhantsev A. N. Mal’gin V. N. Poloskov A. Yu. Terzhevik N. N. Filatov 《Water Resources》2006,33(5):511-522
The results of numerical modeling of Onega Lake climatic circulation are presented. The model used in this study was developed earlier and successfully applied to the reproduction of large-scale hydrodynamical processes in Ladoga Lake. The obtained results are of importance for the development of both models of nonreactive pollutant transport and ecosystem models of the water body. The developed model can be used to calculate currents and temperature fields for individual scenarios of external impacts on the water body, and the results of calculation of the climatic circulation can serve as initial approximations for scenario-based calculations. 相似文献
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O. S. Ermakova Yu. A. Mal’kov D. A. Sergeev Yu. I. Troitskaya 《Izvestiya Atmospheric and Oceanic Physics》2009,45(6):791-798
This is an experimental study of the mixing induced by coincident surface waves in a liquid. The main mechanism leading to
the emergence of mixing was shown to be the middle currents generated by coincident waves. The regime of these currents strongly
depends on the amplitude of surface waves. For waves of near-critical amplitudes, an intense turbulization of middle currents
is observed. Patterns of the velocity field were obtained using the Particle Imaging Velocimetry (PIV) technique for different
amplitudes of surface waves. The results obtained can be used to estimate mixing in the near-surface oceanic layer. 相似文献
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