جستجوی مقالات مرتبط با کلیدواژه "سوخت فسیلی" در نشریات گروه "پزشکی"

One of the most important energy sources is non-renewable sources, including fossil fuels, the release of which causes many harmful consequences, including respiratory diseases, growth disorders, etc. On the other hand, renewable energies, including water, wind, sun, etc., are sustainable energy sources and compared to traditional fossil fuels, they have less adverse environmental effects due to the minimal emission of greenhouse gases. Due to the need to use renewable energy to reduce greenhouse gas emissions and combat climate change, the widespread use of these resources will bring about sustainable development. Therefore, creating the necessary infrastructure to use renewable energy as an important solution plays a key role in preserving natural resources. The purpose of this study is to review green and renewable fuels; Their sources, applications, advantages, and limitations. In this narrative review study, review articles, research articles, and cross-sectional descriptions were published until the beginning of February 2023 in English and Persian related to green and renewable fuels; Sources, applications, advantages, and limitations were investigated. These articles were searched in ScienceDirect, PubMed, Google Scholar, Web of Science, Scopus, and SID databases, using keywords such as renewable energy, fossil fuel, green fuel, and non-renewable energy with the aim of better understanding green fuels; Their sources, application, advantages, and limitations were obtained. After searching the databases with the mentioned keywords, 78 articles were included in the study. After removing duplicate articles, studying the abstract, and finally the full text of the articles, 35 related articles were included in the study. Endnote X7 resource management software was also used to organize, study titles and abstracts, and identify duplicate articles. Gren fuel is a non-toxic fuel that is essentially free of sulfur and aromatic compounds and is produced through various technologies such as biological and thermochemical processes. All the reviewed articles in the direction of producing green fuels such as biodiesel, natural gas, and hydrogen have pointed to the reduction of greenhouse gas emissions, improvement of air quality, stability of combustion in engines with dual fuel performance, and reduction of the negative effects of air pollution on health. Green fuel production is promising, but it faces limitations and challenges such as the need for land, water, and other resources, which can lead to changes in land use patterns, deforestation, and biodiversity loss. Also, the costs of producing biofuels depend on important factors such as raw materials, land, agricultural inputs, subsidies, and production technology. Biofuels are usually more expensive than fossil fuels and their production requires initial investment and maintenance costs. Considering the limitations and challenges of producing or using green fuel, using these renewable energy sources requires environmental planning and policy. Green fuels and renewable energy sources have emerged as promising solutions to deal with the environmental challenges caused by traditional fossil fuels. In general, green fuels offer a glimpse of a more sustainable future. However, their environmental effects need to be carefully investigated. Hence, a comprehensive understanding of diverse green fuel production methods and renewable energy technologies, along with their potential ecological impacts, is necessary to ensure the alignment of these alternative energy sources to achieve sustainable development.

Transportation sector generates the largest share of greenhouse gas emissions (CO2 and CH4) which causes global warming. “Stop-and-go” driving and congested traffic flow results in a decrease in average car speeds, an increase in traffic incidents, and finally escalates GHGs emissions. Hence, congestion is directly related to carbon emissions. The objective of this study was to estimate the GHGs emissions of urban transportation sector using the congestion index.

The traffic flow in the main street of Hamadan city was continuously monitored in 8 time periods from 8 am to 12 pm in August 2018. Then, a traffic congestion map was prepared. Subsequently the surface area and weight coefficient of each road were obtained based on the traffic assignment model. Finally, the amount of GHGs emissions from transportation sector, CO2 emission per capita, and annual amount of CO2 and CH4 release in each street were calculated and estimated.

Results showed that the total CO2 and CH4 emissions from the transportation sector of Hamadan city are 776000 and 396 ton/year, respectively. Imam Khomeini Highway (29166 ton CO2/year) and Mirzadeh Eshghi Street (24453 ton CO2/year) recorded the highest level of carbon emission due to the highespeed and more width “stop and go” driving conditions.

The conformity of the congestion index with the traffic assignment model can be used to estimate the amount of urban traffic pollution. Finally, because of the high growth rate of CO2 and CH4 and the role of forests in maximizing carbon sequestration, it is imperative to manage and increase green spaces to reduce CO2.