air conditioning refrigerant r134a has value of global warming potential (gwp) 1300, which is much higher than mac directive (gwp below 150) passed in july 2006. this prompted a search for alternative refrigerant with gwp value less than 150. r1234yf is a new refrigerant which has lower gwp value of 4. effect of blower speed has been compared and flammability issue of r1234yf has been addressed...

In recent years, increasing the awareness on the environmental problems, especially global warming, has increase the concerns about the impact of emissions on the global climate. The current study was conducted to evaluate and analyze the environmental effects of rapeseed production in the form of life cycle using SimaPro software with the aim concentration on climate changes and impact of acid...

by increasing crops yield due to intensive use of agricultural machinery and energy inputs, utilizedenergy in agriculture has been increasing rapidly which negative environmental impacts on water,air and soil are its consequences. in this paper, potato production in isfahan province was studiedusing life cycle assessment approach from the standpoint of energy consumption and environmentalimpact...

Transportation is an important part of modern community life as well as one of the largest sources of greenhouse gas emissions in urban communities, the population growth of which can increase transportation capacity. Monorail systems are relatively new rail transportation systems which are currently being designed and constructed in different countries. We have applied the Intergovernmental Pa...

Transportation is an important part of modern community life as well as one of the largest sources of greenhouse gas emissions in urban communities, the population growth of which can increase transportation capacity. Monorail systems are relatively new rail transportation systems which are currently being designed and constructed in different countries. We have applied the Intergovernmental Pa...

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original article   introduction: direct sunlight and increased heat load influence mental and physical health of workers negatively and result in performance impairment. activity reduction is a natural body response to increase in internal body temperature, and a compensatory mechanism to make body balanced. this study was carried out to estimate productivity loss due to heat exposure among ira...

climate change disturbs the distribution of precipitation patterns and affects water resources. a lot of evidences imply that the increased atmospheric concentration of greenhouse gasses in turn increases the precipitation changes around the world. thus, since iran is located in an arid zone of the earth, identifying the effects of co2 concentrations on iran precipitation rate is highly importa...