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Background and Objectives: As a green fuel and environmentally friendly energy, biodiesel has recently attracted much attention and efforts are ongoing to optimizing biodiesel production from microalgae’s. The aim of this study was to determine the appropriate method of dewatering and drying biomass and selecting a suitable organic solvent for extraction lipids from biomass. Materials and Methods: After culturing Nannochloropsis Oculata in Gillard F/2 medium and reaching at the end of the stationary growth phase, algal biomass was separated from aqueous by centrifuge and drying in three methods: fore, air-dried and lyophilized. Lipid extractions of each sample was performed using soxhlet apparatus and three solvents including diethyl ether, n-hexane and n-pentane. At each stage, the quantity and quality of the extracted lipids was determined by gas chromatography. Results: In all three drying methods, palmitic acid and palmitoleic acid were significantly the main fatty acid composition of microalgae. The fatty acid composition of palmitic acid extracted by diethyl ether was significantly more than the other two solvents. Maximum production of triglyceride was observed in air dried and lyophilized (using diethyl ether solvent) microalgae as 75.03 and 76.72 % of fatty acid respectively. Conclusion: The use of lyophilized method for dewatering and drying of biomass and diethyl ether as solvent for the extraction of lipids from biomass yielded more compared with other methods studied in this paper and would be more efficient in research works related to the production of biodiesel from microalgae’s lipid.

Due to the growing demand for electricity it is inevitable to have new power plants. Given the large share of electricity production in thermal power plants, construction of gas burning power plants have particular importance. Because of the high construction cost of the new plants, it is advisable to start with improvement of the efficiency in the existing and plates. One important index in electricity industry, is the efficiency of power plants which concerns all the powerplants in the world. In order to increase it as much as possible, and reduce the loss of energy to a reasonable degree, this paper examined the performance impact of plant life and obtained 0.07 of electricity coefficient for the variable. We also examined other factors related to efficiency. Among the factors influencing efficiency of this type of power plants, the cost of fuel and average plant life and volume of production of electricity were also important. In this study a panel data from 34 gasplants in Iran was used for a period of 4 years (2008-2011).

Background and aims: Fossil fuels Emission and their limited resources make to use renewable energy with more sustainable energy sources and less minimal environmental impacts. One of the most appropriate renewable energies considered lots of advantages including being renewable and environmentally friendly and containing social and economical interests, is Biomass. “Biomass” means a power source that is comprised of, but not limited to, combustible residues or gases from forest products manufacturing, waste, byproducts, or products from agricultural and orchard crops, waste or co-products products from livestock and poultry operations, waste or byproducts from and food processing, urban wood waste, municipal solid waste, municipal liquid waste treatment operations, and landfill gas. Due to the wide availability of biomass worldwide, mainly because it can be obtained as a by-product of many industrial and agricultural processes, biomass represents a growing renewable energy source with high growth potential. Biomass helps reduce the amount of GHG that give more impact to global warming and climate change. The biomass emissions level is far smaller compared to fossil fuels. The basic difference between biomass and fossil fuels when it comes to amount of carbon emissions is: all the CO2 which has been absorbed by plant for its growth is going back in the atmosphere during its burning for the production of biomass energy. While the CO2 produced from fossil fuels is going to atmosphere where it increases greenhouse effect. Another great advantage of biomass energy is that it is an indigenous fuel. The fuels from biomass materials can be produced locally and no high technology is required. Producing fuel from biomass materials reduces the dependence of a country on foreign resources for their fuel requirements. Moreover, since this indigenous fuel is labor intensive, it can contribute to the generation of new jobs, particularly in rural and farming communities. The number of employed workers required is 3-6 times greater than the fossil energy production in the associated processes. This study was aimed to identification and green grading of environmental management in that’s jobs. Some other socio-economic benefits can be counted such as slowing down the migration from the rural areas to cities, decreasing the issues associated with rapid urbanization, and developing a biodiesel production industry. Among its great benefits is the forest use of the territory, which would also serve to clean the forest and thus prevent forest fires, and the ability to generate jobs. Biomass generates continuous employment such as the extraction of raw materials from the countryside and the bush. This study was aimed to identification and green grading of environmental management in that’s jobs. The research questions are: 1. What are green job indicators? and 2. has renewable energy biomass business indicators of green jobs? Methods: This study was qualitative – quantitative, first according to the grounded theory qualitative method semi-deep interviewed with 50 environmental experts in the Environmental Protection Agency, the municipality, faculty members of the universities, the natural resources and watershed management, agriculture ministry and NGOs active in the environment conducted a with purposeful sampling (snowball). Regarding qualitative data validation were used constant data comparison, reviewing the observers and handwriting by participants and use of foreign and expert researchers familiar with qualitative research as an observer. Then, data was analyzed using the grounded theory of open, axial and selective coding analyzed in MAXQDA software. Once coding categories emerge, the next step is to link them together in theoretical models around a central category that hold everything together. In order to explain the grounded theory, green jobs are considered as the central variable, and the main line of research is defined using reminders and diagrams around it, and finally the green indicators derived from it are developed. Based on them, researcher-made questionnaire was designed in a combination, closed response with 5-rate likert scale. In order to determine the validity of the questionnaire, the content validity was used with the lawshe model and with reviewing previous studies was determined, the scope of the questionnaire in greenness of the job, and the reliability of the questionnaire was obtained using Cronbachchr('39')s alpha coefficient for internal consistency. Cronbachchr('39')s alpha value for each research question was more than 0.7, the reliability of the questionnaire was approved. Also, the Cronbachchr('39')s alpha coefficient of the questionnaire was 0.890. In order to estimate the repeatability, the retest method and the ICC index were used that index was 0.996 (p <0.001), indicating its high repeatability. For estimating the results of greenness and its degree in the jobs of renewable energy biomass, were used statistical analysis of Kolmogrov-Smirnov test, single-sample t-test and Friedman test in SPSS software. Result: Findings of the qualitative research on the structure of green job identification and prioritization were discussed in six categories including establishment in accordance with the legal and technological infrastructure of the green job as context, green job as a phenomenon, environmental pollution elimination and the health risks reduction of the community as causal conditions, green management as operational strategies, environmental empowerment of jobs as an intermediary conditions and economic and environmental benefits as a consequence. The results of quantitative to showed that jobs studied are considered green jobs and their green grading are as follows: 1. Maintenance (mean=5/61), 2. System Design (mean=4/83), 3. Training (mean=4/22), 4. Quality Monitoring and Quality (mean=4/03), 5. Collection (mean=3/64), 6. Manufacturer (mean=3/61) and 7. Worker and System Administrator (mean=2/06). According to the results, components of green jobs are defined including: (1. explaining Green Jobs, Productivity of Occupations, 2. environmental Protection and Health, 3. Green potentials and incentives, 4. environmental Standards and Indices of Health and Green Management, 5. environmental and health challenges and solving energy crisis with the help of green jobs, 6. environmental education and green culture, 7.environmental empowerment through a variety of environmental and health education, informing and accompanying NGOs, 8. economic-ecological profitability and the optimistic approach to economic interests (green economy) and impact of economic issues, profitability, financial support, market regulation, and return on investment in the process of greening and green expanding businesses). Results show that green indices of occupations are 1- environmental and health of profile occupational, 2- strengths and weaknesses, threats and opportunities green jobs, 3- green supply chain management of businesses, 4- impact of green jobs on sustainable development and community health, 5- effect of environmental education on the green performance of occupations, the impact of environmental advertising on green performance and 6- reduce employee costs and increase business profits through environmental management. These green jobs literature extols the virtues of generating energy using “wood waste and other byproducts, including agricultural byproducts, ethanol, paper pellets, used railroad ties, sludge wood, solid byproducts, and old utility poles. Several waste products are also used in biomass, including landfill gas, digester gas, municipal solid waste, and methane. Conclusion: The green features of the biomass business are included solving the problem of fossil fuels, caused by fossil energy and renewable energy sources. identification and green grading jobs diversifying energy sources, sustainable development, securing energy, removing environmental and health problems would help to managers and policy makers for identifying and providing executive solutions and identifying multifaceted priorities for green management. Despite the high potential of bio-economy in renewable energy (biomass) and high amounts of raw materials in the agricultural waste and sewage has not been fully realized. To achieve of developing a competitive economy, low-carbon resources with efficient resources, global economic markets have shifted strategy towards renewable energies, so as to create green jobs in order to reduce environmental problems (waste and climate change). For performance of macroeconomic policy in notification Supreme Leader on the restructuring of the countrychr('39')s economic structure has proposed policies to change reducing dependencies on fossil fuels and external resources towards the creation and development of green jobs in the field of renewable energy, especially biomass, because there are a lot of raw materials in the country, especially in the villages and without necessary to high technologies. Biomass development increase energy efficiency, the use of renewable energy resources and the creation of a favourable environment for investment in energy efficiency measures and the generation of ‘green’ jobs. The rural development prospects for green job growth are mixed. Rural areas contain biomass feedstocks which will be increasingly relied upon to offset fossil fuel dependencies. The distribution of those feedstocks, however, is not uniform across rural areas. Furthermore, the technologies to convert those feedstocks into fuels and other uses are yet to be demonstrated at commercially successful scales. Both policy development and research activities should be focused on the efficient utilization of rural natural resources, human capital, and rural infrastructure in achieving national green policies. The green economy appears to be fertile ground for unbiased, academic research to examine some of the regional consequences of green jobs growth and green jobs policies, to include an examination of rural opportunities, but going well beyond that dimension to include the integration of statewide and multi-state regional development opportunities as well as consequences. This study was not about raw materials (waste and sewage) to produce renewable energy biomass, and it is possible that this section may also be effective in the creation and development of green jobs, then there may be restrictions on the generalized findings, interpretations, and attributes of the causation of variables. Therefore, it is suggested that future research into this part of the process of producing renewable energy biomass should be considered.

Iran is located in the dry belt of the earth and is predicted to face water stress in the next half-century. Currently, the area of sugarcane cultivation in Khuzestan is over 85,000 hectares and due to the high water needs of sugarcane and drought conditions, optimization of water consumption and irrigation management is necessary to continue production. Therefore, in this study, the values of soil moisture, canopy cover, biomass yield in five treatments and irrigation levels (start of irrigation at 40%, 50%, 60%, 70%, and 80% soil moisture discharge) during 2 planting dates in the crop year 2015-2016 on sugarcane cultivar CP69-1062 in Amirkabir sugarcane cultivation and industry located in the south of Khuzestan was simulated by AquaCrop model. The measured data on the first culture date (D1) and the second culture date (D2) were used to calibrate and validate the model. The results of NRMSE statistics in canopy cover simulation in calibration and validation sets with values of 2.1 to 15.6% and 3.8 to 18.3%, respectively, and in biomass simulation with values of 6.2 to 15.2%, and 9.5 to 12.6%, respectively and coefficient of determination (R2), range 0.98 to 0.99 indicated that the high ability of the AquaCrop model in simulation canopy cover and biomass yield. whereas, the values of NRMSE of soil depth moisture in the calibration and validation sets ranged from 11.6 to 23.8, and 12.2 to 22.7, respectively, with a coefficient of determination (R2), 0.73 to 0.96 (calibration) 0.8 to 0.93 (validation) showed less accuracy of the model in the simulation. The best scenario is related to the third proposal that water consumption, water use efficiency, and yield are 1710 mm, 1.53, and 42.27 tons per hectare, respectively, which shows a reduction in water consumption of 360 mm.

Climate change is a serious challenge to human interest by its adverse effect on various sectors, such as water sources, agriculture, and energy. According to IPCC report, the average annual temperature of the earth has been raised between 0.3 to 0.6º because of the spread of the greenhouse gases, and this report predicts this amount will increase between 1 to 3.5º until 2100(Boberg et al ,2010). To study the effect of greenhouse gases in the atmosphere and the oceanic-atmospheric, general circulation model in regional scale is the most efficient vehicle. These models have been developed to simulate the current climate. They also performed well in predicting future changes in the climate and simulating interactions of soil, atmosphere, and oceans (IPCC, 2007). The effect of climate change on water sources is assessed using rainfall-runoff models by simulating hydrological processes. Studying future climate change and its likely events will help planners and water sources administrators to cope with the future challenge. Considering these likely changes will contribute to objective planning toward optional operations. Predicting future runoff value is one of the most important factors about dam construction, water transferring, agricultural growth and industrial activities.  Semenov (2008) assessed LARS-WG performance by data from 20 representative stations. Babaeian et al, (2004) and Khaliliaqdam, et al( 2013), studied the effect of climate change on the hydroelectric reservoir of Jor Dam by the microclimate model LARS-WG and scenarios B1, B2, and A1B. Output results of the model showed that Tmin and Tmax will increase to the amount of o.3-0.6 degrees. As a result, available water reservoirs of behind the dams for hydroelectric generation are affected by the decreased rainfall. BaniHabib et al, (2016), simulated the input flow of Shahcheraghi Dam using the generator LARS-WG, data downscaling, and the function of artificial neural networks on output of LARS. They found that nightly and daily temperatures rise 1.1 and 1.2 degrees from 2015 to 2040, and rainfall will decrease by 9% during January. By simulating artificial neural networks, it was determined that the input flow will experience 2.4-4.1 % decrease based on different scenarios.

Introduction and purpose: Energy consumption is on a rapidly growing trend in the world. Accordingly, the non-renewable energy sources are expected to be run out in the future. This issue has resulted in the establishment of efforts targeted toward the development of new energy-generating methods around the world. Biogas energy is one of the new and clean energies that is produced from the anaerobic digestion of biomass wastes. Anaerobic digestion is a cost-effective and environment-friendly method, which facilitates fertilizer and biogas production as well as landfill leachate treatment. Given the high environmental hazards of leachate and its mixture with animal wastes, the present study aimed to estimate the possibility of producing biogas in various mixture ratios. Methods: In this pilot-scale experimental study, the landfill leachate of Mashhad, Iran, were mixed with caw fresh dung in different ratios, but same conditions, under anaerobic digestion. This was conducted to consider the ability to produce methane gas in different proportions and landfill leachate. At the beginning and end of the project, the parameters of EC, pH, VS, TS, COD, TOC, P, K, N, and Na were measured. Additionally, the composition of the gases produced under different operating conditions was analyzed using gas chromatography mass spectrometry. Results: Gas production began three weeks after uploading and continued for five weeks. The analysis of gas production in three ratios was indicative of the CH4 production in all three proportions. In this regard, 1/1 ratio produced the highest percentage of CH4. No gas production was observed in the two months of study. Other physical and chemical parameters, such as COD, TS, TKN, and TOC were reduced in the given mixtures during the biogas production procedure. For instance, the case with 1/1 ratio, which showed the best results, had almost 80% decrease in the given parameters. However, no gas production or change of parameters were observed in the control sample (leachate), which was examined for two months. Conclusion: The findings of the study revealed the possibility of producing biogas out of the mixture of waste leachate and animal wastes. Biogas reduces the risk of waste leachate disposal to the environment and facilitates the production of fertilizers containing nutrients (e.g., Na, K, N, and P), which are standard regarding such parameter as pH, EC, C/N, and reduced VS. Moreover, these gases are cost-effective and environment-friendly.

As wind power continues its rapid growth worldwide, Offshore Wind Turbines (OWTs) are likely to comprise a significant portion of the total production of wind energy. These kinds of wind turbines cause of their placement environment should resist in great stormy conditions, which cause fatigue failures. Fatigue loads are one of the main failure reasons in offshore structures. One of the best ways for decreasing these kinds of loads is reducing the structure vibration. In this research application of a tuned mass damper with different masses, in an offshore Tension Leg Platform (TLP) is investigated. Tuned Mass Dampers (TMDs) modeled in a developed code FAST-SC. Results show that using TMD in the nacelle can reduce the moments in the base of the tower and turbine vibration. This reduction can also increase time until failure factor of the OWTs.