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1.
Environ Pollut ; 285: 117390, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34049129

RESUMEN

This paper presents the results of experimental research into the component composition of gases and ash residue from the combustion of a set of high-potential coal-water slurries containing petrochemicals. We have established that the use of slurry fuels provides a decrease in the CO2, CH4, SO2, and NOx concentrations as compared to those from coal combustion. The content of carbon monoxide and hydrogen in the gas environment from the combustion of slurries is higher due to the intense water evaporation. It is shown that adding biomass allows a further 5-33% reduction in the emissions of nitrogen and sulfur oxides as compared to the coal-water slurry and the composition with added waste turbine oil and a 23-68% decrease as compared to coal (per unit mass of the fuel burnt). The mechanisms and stages of CO2, SO2, and NOx formation are explained with a view to controlling gaseous anthropogenic emissions and ash buildup. The values of the relative environmental performance indicator are calculated for slurry fuels. It is shown to exceed the same indicator of bituminous coal by 28-56%.


Asunto(s)
Contaminantes Atmosféricos , Carbón Mineral , Contaminantes Atmosféricos/análisis , Carbón Mineral/análisis , Gases , Pirólisis , Agua
2.
Environ Pollut ; 258: 113682, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31812529

RESUMEN

The active use of solid fossil fuels (coal) in the production of heat and electricity has led to significant pollution, climate change, environmental degradation, and an increase in morbidity and mortality. Many countries (in particular, European ones, China, Japan, the USA, Canada, etc.) have launched programs for using plant and agricultural raw materials to produce heat and electricity by burning them instead of or together with traditional fuels. It is a promising solution to produce slurry fuels, based on a mixture of coal processing, oil refining and agricultural waste. This paper presents the results of experimental research into the formation and assessment of the most hazardous emissions (sulfur and nitrogen oxides) from the combustion of promising coal slurry fuels with straw, sunflower and algae additives, i.e. the most common agricultural waste. A comparative analysis has been carried out to identify the differences in the concentrations of sulfur and nitrogen oxides from the combustion of typical coal, coal processing waste, as well as fuel slurries with and without plant additives. It has been shown that the concentration of sulfur and nitrogen oxides can be reduced by 62-87% and 12-57%, respectively, when using small masses of plant additives (no more than 10 wt%) and maintaining high combustion heat of the slurry fuel. However, the use of algae and straw in the slurry composition can increase the HCl emissions, which requires extra measures to fight corrosion. A generalizing criterion of slurry fuel vs. coal efficiency has been formulated to illustrate significant benefits of adding plant solid waste to coal-water slurries containing petrochemicals. Straw and sunflower waste (10 wt%) were found to be the best additives to reduce the air pollutant emissions.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/prevención & control , Carbón Mineral , Óxidos de Nitrógeno/análisis , Azufre/análisis , Canadá , China , Helianthus , Japón , Tallos de la Planta , Agua
3.
J Colloid Interface Sci ; 553: 557-566, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31238226

RESUMEN

HYPOTHESIS: Contact line movement over laser-textured metal alloy surfaces depends on the texture, droplet state, inversion of wettability, and liquid flow rate. EXPERIMENTS: Ordered and anisotropic textures were created by a nanosecond pulse laser on aluminum-magnesium alloy surfaces. Microrelief was studied on a profilometer and scanning electron microscope. Changes in wetting properties and the characteristics of spreading were obtained. To implement wetting cycles, liquid was dispensed with a syringe pump using the bottom-up method. FINDINGS: The results provide new, in-depth knowledge to understand the mechanisms of the contact line movement on laser-textured metal surfaces. We have shown that by creating a texture with given parameters (ordered or anisotropic), it is possible to predict a change in wettability from superhydrophilic to hydrophobic, as well as a droplet state. In this paper, we have demonstrated that the contact angle hysteresis determines not only the deviation of the contact angle from equilibrium, but also the adhesion force between the droplet and the surface, a droplet state (Wenzel or Cassie-Baxter), and the wetting anisotropy of local areas on laser-textured alloy. We have recorded two states of the droplet on formed textures: the Wenzel with air cushions on anisotropic and the Wenzel with complete filling of cavities with water on ordered textures.

4.
Vestn Otorinolaringol ; 82(4): 60-63, 2017.
Artículo en Ruso | MEDLINE | ID: mdl-28980600

RESUMEN

This article was designed to report the clinical case of the radicular cyst localized in the maxillary sinus of the 23 year-old man that had been detected before the surgical intervention was undertaken for its treatment. In the preceding visits of the patient to other medical settings, this condition was misinterpreted as a genuine (rhinogenic) cyst. It accounted for the choice of the inadequate surgical strategy for the management of this pathology. As a result, the patient experienced two relapse episodes of the disease. The thorough analysis of the patient's medical history and CT images of the sinus obtained during the 4 year follow up period allowed to establish the definitive diagnosis of odontogenic cyst of the upper jaw. The authors present a brief overview of the relevant scientific literature concerning etiology and pathogenesis as well as the methods of diagnostics and treatment of radicular cyst of the upper jaw.


Asunto(s)
Periodontitis Crónica , Seno Maxilar , Procedimientos Quírurgicos Nasales/efectos adversos , Enfermedades de los Senos Paranasales , Quiste Radicular , Extracción Dental/métodos , Adulto , Periodontitis Crónica/complicaciones , Periodontitis Crónica/diagnóstico , Periodontitis Crónica/cirugía , Diagnóstico Diferencial , Humanos , Masculino , Seno Maxilar/diagnóstico por imagen , Seno Maxilar/patología , Sinusitis Maxilar/diagnóstico , Sinusitis Maxilar/etiología , Sinusitis Maxilar/cirugía , Procedimientos Quírurgicos Nasales/métodos , Enfermedades de los Senos Paranasales/diagnóstico , Enfermedades de los Senos Paranasales/etiología , Enfermedades de los Senos Paranasales/fisiopatología , Enfermedades de los Senos Paranasales/cirugía , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/cirugía , Quiste Radicular/diagnóstico , Quiste Radicular/etiología , Quiste Radicular/fisiopatología , Quiste Radicular/cirugía , Recurrencia , Reoperación/métodos , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento
5.
Izv Akad Nauk Ser Biol ; (4): 441-8, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-26415285

RESUMEN

This paper studies morphometric parameters (body weight, weight of internal organs, body size, etc.) in 170 elk of various sex and age obtained in the Vyatka taiga area in winter. A number of physiological parameters (specific metabolism and thermal conductivity, heat loss rate, etc.) characterizing the metabolic rate and energy balance in the body were calculated for model animals (calf, male, and female). It is noted that in the transition from the first to the second half of winter the specific metabolism in model animals decreased from 20.6, 16.9, and 15.9 to 18.7, 15.4, and 14.5 kcal/(kg day), respectively. It is shown that changes in the rhythm of motor activity of elk are synchronized with the daily air temperature and the maximum flight distance depends on the amount of energy received by the body with food.


Asunto(s)
Aclimatación/fisiología , Adaptación Fisiológica , Metabolismo Energético/fisiología , Rumiantes/fisiología , Animales , Tamaño Corporal , Frío , Femenino , Masculino , Estaciones del Año , Temperatura
6.
Urologiia ; (2): 11-3, 2010.
Artículo en Ruso | MEDLINE | ID: mdl-20967989

RESUMEN

Clinical experience with administration of extracorporeal shock wave lithotripsy (ESWL) in an outpatient clinic demonstrates feasibility of urolith fragmentation in some patients using certain lithotriptors. Concrements can be removed from about 97.0% patients without their hospitalization.


Asunto(s)
Atención Ambulatoria/métodos , Litotricia/métodos , Urolitiasis/terapia , Adolescente , Adulto , Anciano , Femenino , Humanos , Litotricia/instrumentación , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Ultrasonografía , Urolitiasis/diagnóstico por imagen , Adulto Joven
7.
Izv Akad Nauk Ser Biol ; (5): 597-606, 2008.
Artículo en Ruso | MEDLINE | ID: mdl-18956739

RESUMEN

The abundance, species diversity, and spatial distribution of small mammals were studied in two localities in southern Vietnam: the Cat Tien National Park and the Binh Chau Nature Reserve. Rodents were trapped on the ground and in the tropical forest canopy (2-12 m above the ground), marked, and released on the spot. Species diversity of small mammals in undisturbed tropical forest (9 species) was higher than in disturbed tropical forest (14 species). The rat Maxomys surifer and the squirrel Callosciurus flavimanus were dominant. In undisturbed forest, the frequencies of rodent occurrence on the ground and in the canopy were of the same order; in disturbed forest, rodents occurred in the canopy an order of magnitude less frequently than on the ground.


Asunto(s)
Biodiversidad , Murinae/fisiología , Sciuridae/fisiología , Árboles , Clima Tropical , Animales , Vietnam
9.
Izv Akad Nauk Ser Biol ; (4): 442-54, 2001.
Artículo en Ruso | MEDLINE | ID: mdl-11525125

RESUMEN

The architectonics of spines and hair was studied in Neacomys spinosus, Arvicanthis somalicus, Leopoldamys sabanus, L. edwardsi, Maxomys moi, M. surifer, Niviventer fulvescens, N. confucianus, N. cremoriventer, Acomys cahirinus, A. somalica, Hystrix indica, H. cristata, Atherurus macrourus, Erethizon dorsatum, Proechimys steerei, and Lonchotrix emiliae. The presence of a dorsal longitudinal furrow covered by a modified cuticle is a common structural feature of spines in all studied species except E. dorsatum, H. indica, and the frontal surface of the mosaic (scales located side by side) and terrace cuticle (steps between scales) varies in different species from smooth to rib-folded. A terminology has been proposed to describe the main structures of spine and hair. The adaptive significance of the spine architectonics in rodents is discussed.


Asunto(s)
Cabello/ultraestructura , Roedores/anatomía & histología , Animales , Especificidad de la Especie
10.
Naturwissenschaften ; 88(3): 123-5, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11402841

RESUMEN

The controversial phylogenetic position of the recently described South-East Asian endemic bovid, Pseudonovibos spiralis, was evaluated on the basis of phylogenetic analyses of originally obtained nearly complete 12S mitochondrial rDNA sequences for this species and Bubalus bubalis and 26 sequences of Bovidae from the Genbank using Cervus elaphus (Cervidae) as outgroup. In most of the phylogenetic analyses performed using PAUP 4.0 (maximum parsimony, maximum likelihood and neighbour-joining), Bovidae consisted of two major clades: Bovinae including the tribes Bovini, Tragelaphini and Boselaphini, and Antilopinae + Caprinae, incorporating all other bovids. In most trees P. spiralis fell within the buffalos (subtribe Bovina) between Bubalus and Syncerus. Therefore, our phylogenetic analyses of bovid mitochondrial 12S rRNA gene sequences suggest the close relationship of this enigmatic species with the buffalos and its placement within the subtribe Bovina.


Asunto(s)
Búfalos/clasificación , Filogenia , Rumiantes/clasificación , Animales , Artiodáctilos/clasificación , Asia Sudoriental , Búfalos/anatomía & histología , Cuernos/anatomía & histología , Funciones de Verosimilitud , Rumiantes/anatomía & histología
14.
Kardiologiia ; 18(1): 37-43, 1978 Jan.
Artículo en Ruso | MEDLINE | ID: mdl-628142

RESUMEN

The article discusses the 10-year experience in the use of radioisotop diagnosis in the practice of an intensive therapy department. The results of the examination of over 300 patients who had been operated on under conditions of extracorporeal circulation are analyzed. With the use of radioactive indicators some new aspects of the pathophysiology of acute circulatory disorders were revealed, among others those related to the problem of blood deposition, the correlation between the functioning of the right and left parts of the heart; the diagnostic possibilities in appraising the causes of the disorders of circulation, functioning of the parenchymatous organs, and tissue blood flow were widened; the therapeutic tactics in the development of hypovolemia, acute cardiac failure, and disturbances in tissue perfusion could be elaborated.


Asunto(s)
Cuidados Críticos/métodos , Cardiopatías/diagnóstico por imagen , Velocidad del Flujo Sanguíneo , Volumen Sanguíneo , Determinación del Volumen Sanguíneo/métodos , Diagnóstico Diferencial , Circulación Extracorporea , Cardiopatías/fisiopatología , Cardiopatías/cirugía , Humanos , Complicaciones Posoperatorias/fisiopatología , Cintigrafía , Albúmina Sérica Radioyodada
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