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This paper develops a dynamic general equilibrium model (DGEMI) for evaluating energy policies in Iran’s economy. DGEMI provides a detailed multisector framework for analyzing economic transition, removal of energy subsidy, and technological change policies. The results show that eliminating energy subsidies (once- for -all or gradually) in the absence of technological progress is in itself insufficient to stimulate the investment and economic growth. Although the energy intensity along with this policy declines over time, its decline can not be attributed to the energy efficiency, since the economy falls into the lower level of new steady state after removing the energy subsidies. On the other hand, the combination of eliminating energy subsidies and technological progress policies provide a strong growth stimulus accompanied by a pronounced increase in productive efficiency and a decline in intensive energy.

Abstract Background and Aim: Increasing energy consumption has created an energy crisis in the world. Fossil fuels are limited and depleting. Biogas is considered a fuel that has attracted the attention of researchers. To increase biogas production, different pretreatments have been utilized. The purpose of this study was to investigate the optimal mixing ratio of Municipal Solid Waste (MSW) and Sewage Sludge (SS), as well as the effects of various conditions of alkaline pretreatment on biodegradability of wastes and the amount of biomethane production. Materials and Methods: This study was done in a laboratory digester with 1 L volume at 37 °C with different concentrations of NaOH in a completely randomized design. Biogas volume, methane volume, and changes in pH were measured daily. Measurement parameters in the anaerobic digestion including total solids, volatile solids, and carbon and nitrogen content in the feedstock were determined according to the APHA standard methods. Results: The optimal mixing ratio of MSW to SS was 60:40 with the highest methane yield of 254.87 mL/g VS. Next, the effects of 2, 6, and 10% NaOH concentrations were evaluated on the amount of gas produced, indicating that 6% NaOH concentration significantly improved waste decomposition. Methane production, VS, and TS removal were compared to the control treatment, and there were increases of 30, 27.94, and 27.25%, respectively. Conclusion:The results showed that the mixing ratio of MSW to SS at 60:40 with 6% NaOH improves the decomposition of organic wastes and increases biomethane production. Keywords: Alkaline Pretreatment; Anaerobic Digestion; Biogas; Municipal Solid Waste; Sewage Sludge

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 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.

Background and Objective: In recent years, management and disposal of municipal solid waste has become a global problem and the most important environmental concern. Anaerobic digestion is a cost-effective solution for treatment of both solid waste and wastewater. The aim of this study was to investigate the positive or negative effects of calcium chloride content in anaerobic digestion process of municipal solid waste and leachate on biogas production. Materials and Methods: Experiments with 8 levels of calcium chloride on co-digestion of municipal solid waste and leachate were investigated in 500 ml digesters under mesophilic conditions in a completely randomized design with three replications. Reactors with a ratio of substrate to inoculum of 2 (on VS basis) were operated and the volume of the biogas was measured daily. Volatile and total solids, carbon/nitrogen of waste, COD, BOD and heavy metals were measured by following APHA. Results: The results of the experiment showed that the pH was decreased with increasing calcium chloride concentration. The highest amount of cumulative biogas production was obtained in CaCl2 of 2 g/L with the highest VS and TS reduction. Higher concentrations of CaCl2 (≥3 g/L) caused a reduction in the degradability of volatile and total solids and, as a result, a decreased performance of the digester. Conclusion: The results clearly confirmed that the addition of calcium chloride was an effective solution to improve biodegradability in co-digestion of the MSW and leachate and consequently to reduce the total and volatile solids and to increase the amount of‌ biogas.

This study investigates the Granger causality relationship between energy consumption, carbon emission and industrial value added, including labor and gross fixed capital formation in the model. We found that energy consumption is Granger cause of carbon dioxide emission and industrial value added. Also results of variance analysis model suggests that the long term effects of variables on their own swings gradually declines, and share of other variables increases.

The main objective of this study is to design and construct the new, spouted bed dryer, for food drying sensitive foods specially. For this purpose, firstly a new design of dryer was planned to achieve the maximum efficiency and flexibility for liquids and solids drying. After constructing and initial setup of spouted bed, basic experiments such as investigation of an inert particles motion, pressure drop, energy consumption were conducted and optimal system requirements for two particle size (5.8 & 7.8 mm) were determined. The results indicated that changes in pressure drop in the dryer chamber containing inert particles are followed from the Ergun equation. Energy consumption in this system is variable in the range of 3-8 kW per hour. Also results reveals that the energy consumption of the new design of spouted bed dryer is less than the spray dryer for liquid foods drying.

Today’s world faces two major crises including environmental pollution due to fossil fuels and the reduction of these fuels, so energy supply through renewable energies has been considered a sustainable solution. The purpose of this study was to assess factors affecting the tendency to use biofuels among villagers. Heads of households in rural areas in Chavarzagh district, Tarom township, Zanjan province formed the statistical population of the study (N=2742). The sample size was estimated using the Cochrane formula (n=161) and samples were selected using multi-stage cluster sampling method. The descriptive and correlational research method was used in this study. The validity of the questionnaire was approved by a panel of related faculty members. Cronbach's alpha coefficient was used to confirm the reliability of the questionnaire (0.70-0.83). Data was analyzed using SPSS 21. Regression analysis showed that risk, attitudes towards biofuels, self-efficacy, training, eliminating subsidies for fossil fuels and encouraging the use of biofuels, increasing public awareness about the benefits of biofuels and perceived barriers explained 40.6 percent of the variation of villagers’ tendency to use biofuels.

The higher levels of essential elements in soil may be caused in optimum yields and crop quality. So it seems to be necessary to examine different levels of nutrients like Fe and Zn on plants and their productivity. To evaluate effects of iron and zinc application on yield and yield components of Pimpinella anisum an experiment was conducted at the research farm of Urmia University in 2009. Treatments, iron application (0, 0.2, 0.4 and 0.6%) and zinc (0, 0.2, 0.4 and 0.6%), were arranged as factorial based on randomized complete block design with 3 replications. Results showed the significant effect of interaction between iron and zinc on the number of seed in per plant,1000 seed weight, biomass yield, seed yield and harvest index (HI). The maximum value of the 1000 seed weight (2.22 g) was obtained from 0% of Fe and 0.2% of Zn, whereas the minimum value of the 1000 seed weight (1.92 g) belonged to 2% of iron and 0% of zinc. The highest number of seed per plant (762), maximum value of biomass yield (2652 kg/ha) and highest of seed yield (1372 kg/ha) were obtained from 0.6 and 0.4 percent of Fe and Zn and the lowest number of seed per plant (272), maximum value of biomass yield (716 kg/ha) and highest of seed yield (470 kg/ha) were obtained from 0 and 0.6 percent of Fe and Zn, respectively. The highest HI (66.18) was obtained at control treatment and the lowest one (46.67) at both 0.4 percent of Fe and Zn. The essential oil percent increase in average values of Fe and Zn spraying. But accumulation of Fe and Zn were the maximum in higher levels of spraying.

Abstract Background & Objective: Agriculture is one of the most important activities, whereas observing ethical dimensions (human, environment, animals, society, economy and policy) are necessary. Therefore the purpose of this study was develop strategies to apply ethics in agricultural in Sonqor County. Materials &Methods: This study is a Qual-Quan research. The study population consisted of experts and farmers producing healthy products in the city of Sonqor (n = 32) who were selected purposefully. Results: Based on results, comprehensive government attention to Agricultural ethic and financial, technical, and legal support from the farm food to the table ( ) as a first strategy and evelopment of good agricultural production for all products, regional, national, international contracts and agreements in order to meet the needs of healthy consumer markets ( ) as a second important strategy was recognized which both of them are among the aggressive strategies. Also result showed that considering ethical actions towards development of sustainable agricultural, allocation of annual budgets, leading agricultural education to ethical agriculture (WO) are the most important conservative startegies. Conclusion: in the current situation in study the, aggressive strategies should be prioritized. This means that with considering the factors affecting the non-observance of ethics in agriculture, instutational development in this area, amend the rules, guidelines and most important social institutions and ethicl norms in the community of farmers need to be addressed in this county. In this regard the approach of farmers and related organizations should be changed toward appliying manifest of ethic in agriculture.