First find of PGE minerals in sulfide ores related to ultrabasic rocks of the IIsk-Kuksher trough,southern Siberia     

A. S. Mekhonoshin  T. B. Kolotilina  L. A. Pavlova 《Doklady Earth Sciences》2008,419(2):435-437

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The influence of geochemical processes in the near-bottom layer on the hydrochemical characteristics of the waters of the Sea of Japan     

P. Ya. Tishchenko  L. D. Talley  V. B. Lobanov  A. P. Nedashkovskii  G. Yu. Pavlova  S. G. Sagalaev 《Oceanology》2007,47(3):350-359

According to the results of the international expedition aboard the R/Vs Roger Revelle and Professor Khromov in the summer 1999, areas with low oxygen contents (below 210 μM/kg) and those with increased contents of dissolved inorganic carbon and phosphates were found that roughly coincided with one another. These areas are located near the bottom on the southwestern slope of the Tsushima Basin in the region of the Korea Strait and on the continental slope in the region of the Tatar Strait in the northern part of the sea at about 46° N. The set of hydrochemical data points to a high geochemical activity in the near-bottom layer of the areas noted. This activity is confirmed by direct observations of the composition of the interstitial water in the sediments collected in the northern part of the sea during the expedition of R/V Akademik M.A. Lavrent’ev in 2003. It was supposed that the main cause of the increased geochemical activity is the runoff of suspended and dissolved matter from the Korea and Tatar straits. In the areas mentioned, the near-bottom waters are characterized by low values of the nitrogen-phosphorus ratio (below 10), which is geochemical proof of the denitrification process occurring under the conditions of high oxygen concentrations characteristic of the Sea of Japan. Based on the value of the annual production in the Sea of Japan, a rate of denitrification equal to 3.4 × 10¹² gN/year was calculated. Hence, it is confirmed that the geochemical processes in the near-bottom layer have a direct influence on the spatiotemporal characteristics of the hydrochemical properties of the waters of the Sea of Japan.  相似文献   

Climate of Russia in the 21st century. Part 1. New evidence of anthropogenic climate change and the state of the art of its simulation     

V. P. Meleshko  V. M. Kattsov  V. M. Mirvis  V. A. Govorkova  T. V. Pavlova 《Russian Meteorology and Hydrology》2008,33(6):341-350

This is the first of three papers devoted to the study of climate change in Russia in the 20th and 21st centuries using ensembles of CMIP3 Atmosphere-Ocean General Circulation Models. Current studies of observed global and regional climate changes are briefly reviewed based on the analysis of the Intergovernmental Panel on Climate Change (IPCC). The anthropogenic nature of climate change is emphasized. It is also noted that the observed warming in Russia is significantly larger than global warming. Alternative hypotheses on causes of global climate changes discussed in some Russian publications are reviewed and their groundlessness is shown. The paper discusses some characteristics of ensembles of CMIP3 models that participated in the preparation of the IPCC Fourth Assessment Report. A model quality index is introduced. The dependence of simulated climate change in Russia on the choice of model ensembles and emission scenarios is considered. It is shown that the climate change in Russia does not depend significantly on the emission scenario choice until the middle of the 21st century.  相似文献   

Modes of Ag occurrence in the loose deposits of dispersal trains at Au-Ag mineral deposits     

R. G. Kravtsova  L. A. Pavlova  Yu. I. Rogozina 《Geochemistry International》2010,48(7):731-736

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First data on forms of gold occurrence in lithochemical sedimental streams of the Gold-Silver Dukat deposit (Northeastern Russia)     

R. G. Kravtsova  L. A. Pavlova  Yu. I. Rogozina  A. S. Makshakov 《Doklady Earth Sciences》2010,434(1):1184-1191

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Stanniferrous granites of Vietnam: Rb-Sr and Ar-Ar isotope age,composition, sources,and geodynamic formation conditions     

Anh  Phan Luu  Vladimirov  A. G.  Kruk  N. N.  Polyakov  G. V.  Ponomarchuk  V. A.  Hoa  Tran Trong  Phuong  Ngo Thi  Kuibida  M. L.  Annikova  I. Yu.  Pavlova  G. G.  Kiseleva  V. Yu. 《Doklady Earth Sciences》2010,432(2):839-845

Doklady Earth Sciences - Stanniferrous granite-leucogranite massifs in Vietnam to which the bedrock and placer commercial deposits of cassiterite are associated (Timtuc etc.) are of late Cretaceous...  相似文献   

An intercomparison of observed and simulated extreme rainfall and temperature events during the last half of the twentieth century: part 2: historical trends   总被引：1，自引：1，他引：0  

Jose A. Marengo  Matilde Rusticucci  Olga Penalba  Madeleine Renom 《Climatic change》2010,98(3-4):509-529

We analyze historical simulations of variability in temperature and rainfall extremes in the twentieth century, as derived from various global models run informing the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC-AR4). On the basis of three indices of climate extremes, we compare observed and modeled trends in time and space, including the direction and significance of the changes at the scale of South America south of 10° S. The climate extremes described warm nights, heavy rainfall amounts and dry spells. The reliability of the GCM simulations is suggested by similarity between observations and simulations in the case of warm nights and extreme rainfall in some regions. For any specific extreme temperature index, minor differences appear in the spatial distribution of the changes across models in some regions, while substantial differences appear in regions in the interior of tropical and subtropical South America. The differences are in the relative magnitude of the trends. Consensus and significance are less strong when regional patterns are considered, with the exception of the La Plata Basin, where observed and simulated trends in warm nights and extreme rainfall are evident.  相似文献   

Origin of REE-rich ferrocarbonatites in southern Siberia (Russia): implications based on melt and fluid inclusions     

Ilya R. Prokopyev  Alexander S. Borisenko  Andrey A. Borovikov  Galina G. Pavlova 《Mineralogy and Petrology》2016,110(6):845-859

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Electron Probe Microanalysis of Environmental Samples: Preparation of Reference Materials, Correction for Particle Size Effects and Representative Results on Sediments Recovered from Snow, Power Station Fly Ash and Bone Samples     

Ludmila A. Pavlova  Ludmila Ph. Paradina  Olga Yu. Belozerova 《Geostandards and Geoanalytical Research》2001,25(2-3):333-344

In this paper we report the results of electron probe X-ray microanalysis (EPMA) that was used to study environmental materials. The mode of preparation and certification of reference samples based on a basaltic glass matrix for environmental applications of EPMA is described. These samples were prepared containing scandium, strontium and barium (from 0.03 up to 7% m/m) and an evaluation was made of homogeneity, their stability to local heating, followed by analysis by independent methods for certification of composition. Matrix correction procedures for the EPMA technique have been developed for particles having a size commensurable with the volume of X-ray generation. An analytical equation for the size factor is proposed and two techniques for selecting optimum conditions for the analysis of environmental samples by EPMA are reported. These procedures provided satisfactory results when utilized in analysing sediments recovered from snow, coal fly ash and the bones of animals and fish, results from which can be used as indicators for evaluating the pollution level of the lower atmosphere, surface and ground water, as well as revealing pollution mechanisms.  相似文献   

Influence of the spatial distribution of energy-dissipating bracing elements on the seismic response of multistorey frames     

Sonia E. Ruiz  Olga E. Urrego  Francisco L. Silva 《地震工程与结构动力学》1995,24(11):1511-1525

Several reinforced concrete frames with different dissipator distributions, and a conventional moment-resisting frame, are compared in order to select the best dissipator distribution from the point of view of seismic response and structural design. The structures with dissipators are designed according to a criterion proposed in the present paper. Each frame is excited with a set of eleven simulated accelerograms. The choice of the best dissipation distribution is based mainly on the differences between the mean of the maximum overturning moments developed at the base of the frames and between the weights of steel reinforcement and concrete resulting from the structural design of each frame. A comparison of initial construction costs of a building with dissipators and a conventional building shows that the former is 3·5 per cent more expensive.  相似文献