In order to improve the environmental performance of diesel engines, the use of renewable energy sources such as biofuels is justified. The factors influencing the processes of fuel combustion and ...issues allowing to properly provide the necessary conditions for the combustion of biofuels in the combustion chamber of diesel are considered. As a result of experimental studies developed biofuel for diesel engine consisting of methanol and methyl ester of rapeseed oil. Experimental studies of the efficiency and environmental performance of the diesel engine on this biofuel have been carried out.
The experience of solving the world's environmental problems from the use of diesel engines allowed us to develop numerous ways to solve them, including the transfer to work on alternative fuels. The ...article presents the classification of alternative fuels. The article discusses the use of biofuel for the diesel engine. The use of alternative biofuels with different chemical composition and local conditions leads to the distinctive performance of the diesel engine. Therefore, for the scientific representation of the actual picture of the power and economic indicators of the diesel engine, experimental studies were conducted when it was operated on methanol and methyl ether of rapeseed oil. According to the results of laboratory and bench studies of load working processes of a diesel engine running on methanol and methyl ether of rapeseed oil, important information about hourly and specific fuel consumption, filling coefficients and excess air, effective efficiency and exhaust gas temperature were obtained. At the same time dependences of influence of modes of operation of the diesel engine on characteristics of power and economic indicators are established and their numerical values are defined. The presented research performance and economic performance of diesel engine demonstrate the applicability of methanol and methyl ester of rapeseed oil as an alternative bio-fuel is not only to improve the excellent service standard and performance indicators, but also to reduce the toxicity and smoke opacity of the exhaust gases, since alcohol, with its more simple structure and small size of molecules is one of the determining factors for a more "clean burning" fuel.
Chronic rhinosinusitis (CRS) is an inflammatory disease of the nose and paranasal sinuses affecting 11% of the European population. Cyclamen europaeum plant extract (CE) has demonstrated efficacy in ...treating acute rhinosinusitis, but its role in CRS exacerbations remains unknown. In this real-life, prospective, epidemiological, observational study, a total of 317 patients with exacerbations of CRS without nasal polyps (CRSsNP) of moderate severity were treated using three different options: oral antibiotics, CE extract nasal spray, or the combination of oral antibiotic with CE extract. The main outcomes were the effect of treatment on sinonasal symptoms and endoscopic appearance after 6 weeks of therapy, and the number of recurrences of CRS exacerbations after 6 months of follow-up. On the top of oral antibiotics, CE extract significantly improved sinonasal symptoms and endoscopic findings and caused a 4-fold reduction of CRS recurrences. When administered in monotherapy, CE extract was at least as effective as antibiotic in monotherapy on relief of both symptoms and reduction of CRS recurrences. In patients with CRS exacerbation of moderate severity, CE extract nasal spray in monotherapy or added to standard antibiotic treatment significantly reduces sinonasal symptoms and CRS recurrences compared to antibiotics in monotherapy.
The remains of the white-toothed shrew
Crocidura kornfeldi
Kormos, 1934 (one skull fragment with almost complete dentition, the fragmental rostral part of a skull with the left upper incisor, a ...maxillary fragment, five mandibular fragments and an isolated upper incisor) from the Lower Pleistocene deposits of the Taurida cave in the central Crimea (Belogorsk district, Zuya village) are described. This earliest European species of the genus
Crocidura
was quite common in the Early Pleistocene of Central Europe and the Mediterranean; for the first time, it is described from Crimea and the entire Eastern Europe.
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•Pressure drop in gliding-flow cartridges with fiber–glass catalysts was studied.•Cartridge internal geometry influences the pressure drop significantly.•ΔP does not depend upon the ...cartridge external shape and catalyst fabric structure.•Equation for calculation of the pressure drop for different cartridges was proposed.•Partial hydraulic anisotropy of the cartridges was found and studied.
The pressure drop in the structured cartridges with fiber–glass catalysts, providing the gliding flow of the reaction mixture along the catalyst fabric layers was studied. It was found that unit hydraulic resistance of such cartridges significantly depends upon the size of the flow passages and the geometry of the structuring gauzes, at the same, practically not depending upon the structure of the fabric and upon the external shape of the cartridge. The dependence of the pressure drop ΔP upon flow velocity v in all cases is close to the second order: ΔP=ζρv2L, while pressure drop coefficient in the cartridges with corrugated gauze practically does not depend upon flow velocity and may be described by empiric equation ζ av=1744∗d−1.58 (m−1) where d – equivalent flow passage size (m). The structured fiber–glass cartridges with structuring gauzes were found to be partially anisotropic, with commensurable pressure drops in case of flow moving along the passages and across passages, but along the catalyst fabric planes, while the pressure drop for the flow perpendicular to the catalyst fabric planes is much higher.
Abstract
Currently, diesels are widely used as a power plant for the global automotive and tractor fleet. Undoubtedly, this cannot but affect the depletion of the world’s fossil fuel reserves and the ...rise in prices for oil and petroleum products. On the other hand, due to the constant increase in the number of power plants and the deteriorating environmental situation, it is no less important to maintain the required level of purity of diesel (D) exhaust gases (EG). This raises the question of finding new alternative energy sources and using them in existing engines. An important task in this case is to maintain the power and economic indicators at the level corresponding to the serial engine. The paper presents the results of studies of the working process of D using methanol (M) and rapeseed oil methyl ether (ROME). The minimum ignition portion of rapeseed oil methyl ether is set, which ensures stable operation of the D both at low loads and at idle, and over the entire load characteristic. The required composition of biofuels for the D under study is determined and recommended as optimal. The effective parameters of the D under load conditions when operating on M and ROME are studied in detail. At the same time, experimental characteristics of the effective indicators of a D running on these alternative fuels are established.
Bee-collected pollen is an essential protein source for honey bee and bumblebee colonies. Its quality directly affects bee health. We estimated the quality of pollen samples using bumblebee ...microcolonies and high-throughput sequencing for the presence of microorganisms. The tested samples of bee-collected pollen were of different quality, as estimated from their effect on the development of bumblebee microcolonies. Based on the pollen quality, we selected a subset of high-quality and low-quality pollen samples to further analyze them for the presence of microorganisms and pathogens. High-throughput sequencing revealed that the most common microorganisms in the bee-collected pollen were Acinetobacter spp. and bacteria of the genera Lactobacillus and Lactococcus. No pathogenic bacteria infectious for honey bees (e.g., those causing American and European foulbrood) or bumblebees have been identified in the analyzed pollen samples. Among potentially harmful microorganisms, there were bacteria from the Enterobacteriaceae family. The fungal pathogens Nosema apis and Nosema ceranae were detected in four samples; Ascosphaera sp. was found in six samples. Several viruses were found in the pollen samples, such as chronic bee paralysis virus, Israeli acute paralysis virus, deformed wing virus, sacbrood virus, and Kashmir bee virus. No correlation between the presence of these microorganisms or viruses and the impact of low-quality pollen samples on the bumblebee development was found. It is possible that factors affecting pollen quality are the absence of certain biologically active compounds or the presence of pesticides.
Abstract
While legal restrictions on the use of fossil fuels are applied to conserve natural resources, mixed alcohol fuels, vegetable oils and their esters are increasingly attracting attention as ...promising alternative sustainable energy sources for cars. The paper substantiates the need for the use of biofuels (BF) in diesel engines (DE) and studies such eco-friendly energy sources as methanol (M) and rapeseed oil methyl ether (ROME). M and ROME potentially lead to some solutions to environmental problems, because for their production, there are quite abundant resources and these energy sources are characterized by relatively low emissions of harmful substances during combustion. The paper presents the results of experimental studies of the toxicity of DE powered by M and ROME, and shows an improvement in its environmental performance.
400-GHz Continuous-Wave Clinotron Oscillator Ponomarenko, S. S.; Kishko, S. A.; Zavertanniy, V. V. ...
IEEE transactions on plasma science,
2013-Jan., 2013-01-00, 20130101, Volume:
41, Issue:
1
Journal Article
Peer reviewed
Experimental results of a 400-GHz clinotron, which is a modification of the backward-wave oscillator, are presented. Development of grating, focusing magnetic system, and electron gun is shown. The ...clinotron tube is designed to use a high-perveance electron gun and thereby enhance the output power and efficiency. An output power of 43 mW is demonstrated at 385 GHz.
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