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Reduction of fossil fuel reservoirs along with the environmental crisis associated with the fossil fuel combustion cause find the renewable and green resource of energies. Ethanol is an alternative fuel that is used as fuel in combination with other fuels and improves combustion efficiency and exhaust gasses properties. In this paper, combustion in automotive engines using different blends of gasoline-ethanol are studied to investigate the emissions of pollutants such as carbon monoxide, carbon dioxide, nitrogen oxides, and sulfur oxides. The simulation results showed that the blend of ethanol - gasoline significantly reduces exhaust emissions contain carbon dioxide, and sulfur oxides. The highest percentage of reduction in emission of greenhouse gasses is observed for 10% (V/V) of ethanol; however, by increasing engine speed, emission of carbon dioxide increases due to increased fuel consumption, while, unburned hydrocarbons and carbon monoxide emissions initially increases with increasing engine speed, and decreases by increasing the engine speed and temperature. Therefore, a mixture of gasoline-ethanol can be used as a substitute for fossil fuels.

Introduction: Evapotranspiration (ET) is an important component of the hydrological cycle, energy equations at the surface and water balance. ET estimation is needed in various fields of science, such as hydrology, agriculture, forestry and pasture, and water resources management. Conventional methods used to estimate evapotranspiration from point measurements. Remote sensing models have the capability to estimate ET using surface albedo, surface temperature and vegetation indices in larger scales. Surface Energy Balance Algorithm for Land (SEBAL) estimate ET at the moment of satellite path as a residual of energy balance equation for each pixel. In this study Hargreaves-Samani (HS) and SEBAL models ET compared to an alfalfa lysimeter data’s, located in Shahrekord plain within the Karun basin. Satellite imageries were based on Landsat 7 ETM+ sensor data’s in seven satellite passes for path 164 and row 38 in the World Reference System, similar to lysimeter sampling data period, from April to October 2011. SEBAL uses the energy balance equation to estimate evapotranspiration. Equation No. 1 shows the energy balance equation for an evaporative surface: λET=Rn–G–H [1] In this equation Rn, H, G and λET represent the net radiation flux input to the surface (W/m2), Sensible heat flux (W/m2), soil heat flux (W/m2), and latent heat of vaporization (W/m2), respectively. In this equation the vertical flux considered and the horizontal fluxes of energy are neglected. The above equation must be used for large surfaces and uniformly full cover plant area. SEBAL is provided for estimating ET, using the minimum data measured by ground equipment. This model is applied and tested in more than 30 countries with an accuracy of about 85% at field scale, and 95 percent in the daily and seasonal scales. In Borkhar watershed (East of Isfahan, IRAN) ASTER and MODIS satellite imageries were used for SEBAL to compare Penman-Monteith model. Results showed that estimated ET of SEBAL were about 20% less than sugar beet ET and about 15% more for maize ET by Penman-Monteith. He concluded the differences may be due to the limited number of satellite imageries which extrapolated ET through the entire growth period and the data obtained from the weather station far from 24 km in the studied area. In another study at Zayanderud Basin, the different irrigation networks were examined using Landsat 7 imageries to increase the spatial resolution of NOAA satellite to determine the energy balance components and actual evapotranspiration. In this study, data from a lysimeter to a depth of 2.5 m and a diameter of 3 meters planted with alfalfa in the Chahar-Takhteh agricultural research station (Agricultural and natural resources research center of Shahrekord, IRAN) was used. The lysimeter (LYS_REF) located in the in the middle of 25 × 40 m (1000 square meter) alfalfa cultivated farm, surrounded by other planted area. The lysimeter used to measure the reference evapotranspiration (ETr) and around alfalfa was used as cold pixels. Materials and Methods: This study was conducted to evaluate SEBAL and Hargreaves-Samani estimated ET models against evapotranspiration measured by lysimeter within the Shahrekord plain. Meteorological data required for a period of 185 days (according to the lysimeter data period) includes minimum and maximum relative humidity (RHmax and RHmin), maximum and minimum air temperature (Tmax and Tmin), wind speed at two meters (U2), precipitation, evaporation rate, sunshine hours, air pressure and dew point temperature obtained from a weather station nearby lysimeter. In order to assess reference evapotranspiration (ETr) models, statistical indices such as the coefficient of determination (R2), mean absolute error (MAE), mean bias error (MBE), root mean square error (RMSE) and index of agreement (d) were used. Results and Discussion: The results showed that RMSE, MAE and MBE for SEBAL model over the lysimeter data were 1.782, 1.275 and -0.272 mm/day and 0.700 for the d index, respectively. Similar indices for the Hargreaves-Samani model were 1.003, 0.580 and 0.290 mm/day and 0.917 for the d index. For HS model results show that RMSE, MAE and MBE values were 0.813, 0.477 and 0.206 mm/day, and 0.930 for the index of d, during the entire growing period (185 days). Conclusion: However, results showed that the efficiency and reliability of the SEBAL model by processing satellite visible, near infrared and thermal infrared bands. The need for irrigation water requirements and ET estimation are noteworthy, during the growth of various plants, which vary and thus the complete time series of satellite imageries is required to estimate the total and annual evapotranspiration.

Due to the importance of limited energy resources in the world, researchers and policy makers pay more attention to energy intensity. The purpose of the paper is to study the effect of structural break on factors influencing energy intensity in Iran during the period of 1979-2013. The Fully Modified Ordinary Least Squares (FMOLS) method was used to estimate co-integrating relationships among variables under study. The results showed that energy price and foreign direct investment had negative effects, and share of industrial value added had a significant positive effect on energy intensity. Then structural break was included in the model as a dummy variable. Findings indicate that 1987’s structural break has reduced the impact of energy price and industrial value added, which points to a decrease in the price elasticity of energy intensity and an increase in productivity of the industrial sector after structural break. However, such break had no significant effect on the relationship between direct foreign investment and energy intensity.

A study on the impacts of soil humidity and artificial shading on growth, biomass production and its allocation to different organs of wild pistachio (Pistacia atlantica Desf.)saplings was carried out in Alborz research station complex (Karaj, Iran). One year seedlings were treated by soil humidity (20, 50 and 100 percent of field capacity) and shading (100, 70 and 50 percent of full sunlight) factors in a split plot experiment based on a randomized complete block design from June to December 2014. Results showed significant impact of oil humidity on height, collar diameter, fresh and dry biomass of leaves and stem as well as on total fresh biomass. Shade significantly decreased height, root and total dry biomass and root to shoot fresh biomass ratio. Moreover, wild pistachio saplings with different soil humidity treatments show different responses to shade. In particular, shade significantly decreases height, fresh leaves biomass and R/S fresh biomass ratio for well-irrigated saplings and increases these parameters for saplings under drought stress. Response trends of different parameters under humidity × shade treatments showed that shade can reduce undesirable effects of drought stress on wild pistachio saplings.

The present article has it's roots in a survey research aiming at investigating the role and position of Iranian National Media(IRIB) in Sustainability Governance Model. In such a model different section of the society should have the necessary balance. The population of the research consists of managers and senior experts of organizations connected with sustainable development of the country. A sample of 573 subjects was selected through Stratified Sampling. Questionnaire instruments and Delphi Method was applied to test the conceptual model. The results show that the Government interferes in society more than any other section and the media section Private Sector and Public Sector are next respectively. Between them the Media interests more with the government and less with Public Sector. Finally the article proposes a sustainability governance model in which all the sectors are balanced and the national media has a key role in the interaction between the sectors. Some solutions are also proposed for the sake of sustainability governance with an emphasis on the role of National Media.

In order to investigate the amount of biomass in Oak (Quercus macranthera) coppice stand, an area of 278 hectare of Khalkhal forest locating at the northeast of Ardebil was selected as the study area. After combining slope, aspect and altitude maps, the number of land form units (polygons) as well as their areas were determined. Then 63 stump sprouts were selected in such a way that all environmental and typological conditions were taken into account. After determining the overall weight of different parts of trees to measure the dry weight as well as the amount of biomass, different parts of trees were delivered to kiln. The woody debris was collected and weighted in an area of 400 cm2 under each stump sprouts. For determining the soil properties and evaluating its relationships with the amount of biomass, soil samples were taken from depth of 0 –10 and 10-30 cm. The mean amount of biomass was 23.4 tons per hectare of which 65.2% were stored in aerial organs, 29.2% in underground organs and 5.6% in woody debris. There was a significant difference between the amount of biomass in different densities of crown cover. Among the physiographic factors, only the altitude had a significant relationship with the biomass. Basal area and diameter at breast height (DBH) exhibit the highest correlation with the biomass.

Energy besides Other factors production is considered the main factor in the growth and economic development and in the performance of different sectors economic can play beneficial roles. Hence, the country authorities should try to predict anything more precise energy consumption in the proper planning and guidance consumption, to control the way they desired energy demand and supply parameters. The aim of this paper reviews Comparison of Neuro-Fuzzy, Artificial Neural Network and Multivariate Regression for Prediction energy consumption in the country. Case study is energy consumption in transportation sector of Iran. So for this review, were used the annual data energy consumption of transport as a variable output of forecast models and data from the entire country's annual population, GDP and the number of vehicle as the input variables. The end results were assessed with of different models (RSE), (ME) and (RMSE). Models evaluation results showed that Neuro-Fuzzy (ANFIS), compared to other models with the highest accuracy is in predicting energy consumption.

In this study, the effect of some soil parameters on the life forms and total aboveground net primary production (ANPP) in meadow rangelands in Fandoghlou region of Namin county in Ardabil Province were investigated. ANPP in 180 plots of 12 by harvesting and weighting method were measured. Eighteen soil samples were collected along transects. Some physical and chemical attributes of the soil were measured by standard methods. The relationship between these parameters and ANPP was performed using multivariate regression (enter) method. To determine the effects of important soil parameters on ANPP variation, principal component analysis (PCA) was used. The results of regression analysis showed that electrical conductivity (EC), magnesium (Mg), spreadable clay (WDC), volumetric moisture content (VM), organic carbon (OC), soluble potassium (KS), exchangeable potassium (Kexch), sodium (Na) and phosphorus (P) were the effective parameters on the life forms and total ANPP (p<0.01). The accuracy of obtained equations for grasses, forbs and total ANPP were calculated 79, 76 and 70%, respectively. Moreover, results of PCA showed that soil parameters justify 84.52 percent of total ANPP variation and in comparison, with regression results with 28% it provides better results.

In the current study, the environmental impacts of tomato paste production were investigated based on the total life cycle of tomato including cultivation, processing, packaging and transportation, using the Centrum voor Milieuwetenschappen Leiden Impact Assessment, (CML-IA) method in Kermanshah regions. The required information was obtained through interviews, questionnaires and, Ecoinvent, LCA Food DK and IDMAT databases. Results showed that among the influential groups, during the production process of one kg of canned tomato paste, the ozone layer depletion and the reduction of organic resources were least effected and the open waters ecotoxicity received the highest impact. In the cultivation process, electricity consumption had the greatest impact on open waters ecotoxicity followed by the nitrogen fertilizer. The factory processing phase had the lowest impact among the influential groups (except open waters ecotoxicity). The energy efficiency was calculated as 0.63 kg/MJ. The net energy gain and the total energy consumption in the tomato farm were -42700 and 44.86 MJ/ha, respectively. The consumption of electricity and chemical fertilizers were the highest amount of input energies with 75.43 and 16.94% respectively. According to the results, the cultivation phase has the adequate potential to reduce the environmental impacts during the tomato paste production through the improvement of irrigation systems to reduce electricity consumption.

In this paper a new magnetic-solar engine for vehicles is proposed. Each cylinder of this engine includes two permanent magnets, which their magnetic forces drive the piston. One of these two permanent magnets acts as the piston of the corresponding cylinder. The other permanent magnet of each cylinder rotates cyclically such that the same and opposite poles of the two magnets are placed against each other periodically. The attraction/repulsion forces generated in this way inside the cylinders are coordinated to drive the crankshaft of the engine. The rotatable permanent magnet of each cylinder is rotated by a DC motor, which is fed by the solar panels of the proposed magnetic-solar engine. One of important advantages of the proposed engine is elimination of expensive and heavy induction motors and their associated equipment. The proposed engine is also equipped with batteries to store/retrieve solar power, which increases the useable time of the engine. The constructed solar-magnetic engine is registered as a patent in the Iran’s patent office with the number of 85138.