ОңТҮстік қазақстан медицина академиясы, хабаршы №4 942, 2021 жыл, том 2
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| nitrogen oxides
(NO x ) are generally minor, and can either be increased or decreased, depending on conditions. NO x emission from combustion of ethanol blends range from a 10% decrease to a 5% increase over emissions from gasoline (OECD/IEA 2004 p. 114). However, if the full life cycle of ethanol is considered, NO x emissions can be significantly higher mainly due to emissions from feedstock production. NO x is released from fertilizers used to grow bioenergy crops, and is emitted mostly outside urban areas. When gasoline is blended with ethanol, emissions of most toxic air pollutants decrease. This is primarily due to the dilution effect of ethanol which substitutes some part of gasoline, which emits toxic air pollutants. For instance, toxic emissions of benzene , 1,3-butadiene , toluene and xylene decrease when ethanol is added. Benzene is a carcinogen, while olefins and some aromatics which are emitted by the combustion of fossil fuels as well, are precursors to ground-level ozone. While few studies have looked at the impacts on pollution levels from high blends, it appears that impacts are similar to those from low blends. The above mentioned toxics benzene, 1.3-butadiene, toluene and xylene, which are emitted by the combustion of fossil fuels, are considered to be more dangerous than emissions of ethanol combustion. During ethanol fuel combustion, emissions of the toxic air pollutants acetaldehyde , formaldehyde , and peroxyacetyl nitrate (PAN) increase relative to straight gasoline. Acetaldehyde is emitted most, but it is a less-reactive and less-toxic pollutant than formaldehyde. PAN is an eye irritant and is harmful to plants. No one of these pollutants is present in the unburned fuel, as they are only created as byproducts of incomplete combustion . Nevertheless, impacts of acetaldehyde and PAN seem to be minor as emissions are relatively low compared to other sources and as they can be efficiently removed by a vehicle’s catalytic converter. References 1. Isaeva A.U., Dayrabaeva A.Zh., Zhaksybek K.K The influence of pesticides on soil micro- organisms, ТМНПК «Ауэзовские чтения – 18: к 175-летию Абая Кунанбаева Шымкент:ЮКГУ им. М.Ауэзова 2020, C. 133-139. 2. Dairabaeva A., Abduova A., Dusenova S. , Askerbekova A. Momin Saya Optimization and organization agrolandscapes sustainable agroecosystems.: Materiály XVI Mezinárodní vĕdecko-praktická konference «Zprávy výdecké ideje - 2020», Volume 5: Praha. Publishing House «Education and Science» - 7-9 s. жүктеу/скачать 3,39 Mb. Достарыңызбен бөлісу:
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