Exact solution for long-term size exclusion suspension-colloidal transport in porous media

Long-term deep bed filtration in porous media with size exclusion particle capture mechanism is studied. For monodispersed suspension and transport in porous media with distributed pore sizes, the microstochastic model allows for upscaling and the exact solution is derived for the obtained macroscale equation system. Results show that transient pore size distribution and nonlinear relation between the filtration coefficient and captured particle concentration during suspension filtration and retention are the main features of long-term deep bed filtration, which generalises the classical deep bed filtration model and its latter modifications. Furthermore, the exact solution demonstrates earlier breakthrough and lower breakthrough concentration for larger particles. Among all the pores with different sizes, the ones with intermediate sizes (between the minimum pore size and the particle size) vanish first. Total concentration of all the pores smaller than the particles turns to zero asymptotically when time tends to infinity, which corresponds to complete plugging of smaller pores.Z. You, P. Bedrikovetsky and L. Kuzmin

Exact Solution for Long-Term Size Exclusion Suspension-Colloidal Transport in Porous Media

Long-term deep bed filtration in porous media with size exclusion particle capture mechanism is studied. For monodispersed suspension and transport in porous media with distributed pore sizes, the microstochastic model allows for upscaling and the exact solution is derived for the obtained macroscale equation system. Results show that transient pore size distribution and nonlinear relation between the filtration coefficient and captured particle concentration during suspension filtration and retention are the main features of long-term deep bed filtration, which generalises the classical deep bed filtration model and its latter modifications. Furthermore, the exact solution demonstrates earlier breakthrough and lower breakthrough concentration for larger particles. Among all the pores with different sizes, the ones with intermediate sizes (between the minimum pore size and the particle size) vanish first. Total concentration of all the pores smaller than the particles turns to zero asymptotically when time tends to infinity, which corresponds to complete plugging of smaller pores

Биохимические и молекулярно-генетические механизмы развития профессиональной бронхолегочной патологии

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Controlling Explosive Sensitivity of Energy-Related Materials by Means of Production and Processing in Electromagnetic Fields

The present work is one of the world first attempts to develop effective methods for controlling explosive sensitivity of energy-related materials with the help of weak electric (up to 1 mV/cm) and magnetic (0.001 T) fields. The resulting experimental data can be used for purposeful alternation of explosive materials reactivity, which is of great practical importance. The proposed technology of producing and processing materials in a weak electric field allows forecasting long-term stability of these materials under various energy impacts

Drought resistance of introgressive spring common wheat lines with genetic material of tall wheatgrass

Background. To breed drought-resistant cultivars of common wheat1 (Triticum aestivum L.), it is important to use the gene pools of its relatives, including tall wheatgrass Thinopyrum ponticum (Podpěra) Z.-W. Liu & R.- C. Wang (= Agropyron elongatum (Host) Beauv.).   Materials and methods. The introgressive lines of spring common wheat with T. ponticum genetic material and standard cultivars were studied in the field in the southern forest-steppe of Western Siberia using generally recognized methods. The ecological plasticity of cultivars and introgressive lines by grain yield and yield components was calculated according to the method of S. A. Eberhart and W. A. Russell. During the research period, there was a prolonged drought in 2012, and irregular short severe droughts occurred in 2013, 2014, and 2017.   Results. An analysis of the ecological plasticity of standard cultivars adapted to the regional conditions showed that cv. ‘Pamyati Azieva’ corresponded to the extensive type, and cvs. ‘Duet’, and ‘Erythrospermum 59’ corresponded to the intensive type. Under drought conditions, the grain yield of cv. ‘Pamyati Azieva’ was determined by the stable development of productive tiller number, seed number and grain yield per main ear, but plasticity in 1000 grain weight was observed. Cvs. ‘Duet’ and ‘Erythrospermum 59’ showed ecological plasticity due to the adaptive development of two or three yield components. Introgressive lines exceeded the standard cultivars in grain yield (1.1–2.2 times) in dry seasons. Five lines were similar to cv. ‘Pamyati Azieva’ in plasticity and stability, and under drought conditions they demonstrated high and stable development of three or four yield components. The intensive lines formed their yield due to the compensatory development of three yield components in different combinations.   Conclusion. Introgressive lines with T. ponticum genetic material are valuable for breeding spring common wheat cultivars with various drought-adaptation mechanisms

Role of homocysteine metabolism in the development of endothelial dysfunction and hypertension in patients with multiple myeloma

The article is devoted to the modern understanding of endothelial dysfunction development, the role of hyperhomocysteinemia, and, as a consequence, hypertension in patients with multiple myeloma receiving multiagent chemotherapy. Considering that the potential of a standard examination does not allow identifying subclinical endothelial dysfunction, using specific techniques is necessary, in particular, to determine the homocysteine level to monitor the endothelial function.The aim of this review was to summarize the current understanding of hypertension etiology and prospects for detecting early, subclinical endothelial changes, including in patients with multiple myeloma.Assessment of endothelial dysfunction can be useful for detecting precisely the subclinical cardiovascular disease in order to stratify the risk of developing cardiovascular events in patients receiving multiagent chemotherapy

Paleontological records indicate the occurrence of open woodlands in a dry inland climate at the present-day Arctic coast in western Beringia during the Last Interglacial

Permafrost records, accessible at outcrops along the coast of Oyogos Yar at the Dmitry Laptev Strait, NE-Siberia, provide unique insights into the environmental history of Western Beringia during the Last Interglacial. The remains of terrestrial and freshwater organisms, including plants, coleopterans, chironomids, cladocerans, ostracods and molluscs, have been preserved in the frozen deposits of a shallow paleo-lake and indicate a boreal climate at the present-day arctic mainland coast during the Last Interglacial. Terrestrial beetle and plant remains suggest the former existence of open forest-tundra with larch (Larix dahurica), tree alder (Alnus incana), birch and alder shrubs (Duschekia fruticosa, Betula fruticosa, Betula divaricata, Betula nana), interspersed with patches of steppe and meadows. Consequently, the tree line was shifted to at least 270. km north of its current position. Aquatic organisms, such as chironomids, cladocerans, ostracods, molluscs and hydrophytes, indicate the formation of a shallow lake as the result of thermokarst processes. Steppe plants and beetles suggest low net precipitation. Littoral pioneer plants and chironomids indicate intense lake level fluctuations due to high evaporation. Many of the organisms are thermophilous, indicating a mean air temperature of the warmest month that was greater than 13 °C, which is above the minimum requirements for tree growth. These temperatures are in contrast to the modern values of less than 4 °C in the study area. The terrestrial and freshwater organism remains were found at a coastal exposure that was only 3.5. m above sea level and in a position where they should have been under sea during the Last Interglacial when the global sea level was 6-10. m higher than the current levels. The results suggest that during the last warm stage, the site was inland, and its modern coastal situation is the result of tectonic subsidence. © 2010 Elsevier Ltd