The knowledge related to the methodology of the Field trial study as a type of intervention studies, yet for many of our researchers is not fully understood. The aim of the current study was a better understanding of conducting this type of research. Field trial studies are done on healthy individuals and aim to prevent. These types of studies such as clinical trials are performed on both individual and collective levels. One type of these studies is Community Intervention Trial which is usually done on a large scale population. Field trial study should be carried out in stages, such as the formulation of hypotheses, selection of the population (reference population, study population, and sampling), measuring the baseline variables (before conducting preventive intervention), random allocation of subjects to intervention and control groups, doing interventions and measuring outcome. The methodology of Field trial studies is very similar to clinical trials. The difference is that Field trials are conducted on healthy individuals and aim to prevent and also the sample size required to this type of study is relatively more, and these studies are usually time consuming and costly.

Combustion of sulfur containing fuels will lead to formation of air pollutants such as SO2 and acid rains. It is not possible to desulfurize all the sulfur-containing compounds of the fuels by the existing sulfur removal methods (such as hydrodesulfurization). Therefore, many researchers have focused on biological sulfur removal. Varios parameters have a great role in isolating biodesulfurizing microorganisms, which are explained in this paper. These papmeters have been considered and as the result, three biodesulfurizing microorganisms have been isolated: BS1 thermophilic bacterium, MS1-1 mesophilic bacterium and WS4 fungus (Stachybotlys sp.). They are able to desulfurize the heavy crude Oil of Soroush Oil Field with 82% (in 6 days), 76% (in 6 days) and 76% (in 3 days), respectively. They are able to remove sulfur and nitrogen from the heavy crude Oil, selectively. Heavy crude Oil biodesulfurization project was initiated by Petroleum Engineering Development Company (PEDEC), a subsidiary of National Iranian Oil Company.

Several emulsions were synthesized using a crude Oil sample named Nowruz as the Oil phase، the deionized water as the water phase and Span 40-type surfactant as the emulsifier and parameters affecting the rheological properties of emulsions were studied. In order to investigate the quality of emulsions، their stability was monitored in a three month period. A power-law model was used for the dependence of emulsion viscosity on shear rate and Liu، Richardson، Mooney، and Krieger-Dougherty models were used for the dispersed phase volume fraction dependency. It was observed that the data obtained from modeling were consistent with the experimental data. The results obtained by microscopic analysis revealed that the phase inversion phenomenon took place in the range of 40 to 50% of the dispersed phase (water) content. Temperature was found to be a significantly effective factor in all the samples including the crude Oil and its emulsions. It was observed that an increase in temperature could cause a considerable decrease in viscosity، shear stress، and dynamic moduli. An increase in water volume fraction caused an increase in viscosity and dynamic moduli up to the phase inversion point and resulted in a reverse trend beyond this point. The investigation of shear rate effect demonstrated a Newtonian behavior for the crude Oil and shear-thinning effect for the emulsions over a wide range of shear rates. The shear-thinning effect increased with an increase in water content and surfactant concentration. The results showed a decrease in loss tangent and a notable increase in viscosity، shear stress، dynamic moduli، and elasticity of emulsions with an increase in surfactant concentration.

The authors discuss the technology for dual pumping technology of Oil-producing wells and show its advantages and shortages. It is concluded that the simultaneous-separate Oil production project proposed is economically attractive due to increment in Oil production, high-income terms, and short pay-off period even in small and depleted reservoirs. Furthermore, the potential of the proposed project is evaluated in terms of the required facilities and incremental Oil production. Dual pumping technology becomes of ever-more use today since the unified well-spacing pattern envisioned for multilayer Field development and operation ensures the feasibility of multiple-zone production, and, as a consequence, ramp-up of reserves recovery and Oil drainage amount as well. At the same time, the practicability of multiple-zone production depends on a number of fraught factors and requires thereof appropriate inventory and current status analyses to be fulfilled with regard to reserves recovery operations. As influx performance study and fluid-bearing characteristics of reservoirs are often incomplete due to Field situation, the authors, therefore, follow the task to carry out an efficient analysis of multi-zone productions based on dual completion technologies.

Because of increasing demand for Oil and gas, it is necessary to properly manage the production in Oil Fields which can be performed through optimization. Azadegan Oil Field has a large volume of Oil reserves shared with Iraq and requires special attention. The main goal of this paper is to introduce and develop mathematical modeling for Azadegan Oil Field to optimize the Oil production using Real-Time Production Optimization (RTPO). Therefore, 13 wells were considered in Manifold No. 7 of Azadegan Oil Field. Due to the nonlinearity nature of Oil production and pressure drop equations in production facilities, Mixed Integer Linear Programming (MILP) was examined to convert nonlinear equations to the linear ones. By solving the equations simultaneously, optimum wellhead pressures were obtained to achieve maximum Oil production. The results showed a 27. 7% increase in Oil production.

To investigate the effect of vermicompost, N fertilizer and their integration on growth, biological and essential yields Oil and its components in two populations (Varamin and Isfahan), an experiment was conducted in a randomized complete block design with three replications in the Field of Isfahan Medicinal Plants Research Center in 2016. Fertilizer treatments including 100% urea, vermicompost 33.3 and urea 66.6%, vermicompost 66.6 and urea 33.3%, 100% vermicompost and control treatment (without fertilizer) as the first factor and Varamin and Isfahan populations as the second factor were selected. The results showed that the interaction effects of nitrogen fertilizer and populations on all studied traits were significant. In both populations, nitrogen fertilizer improved height, biological and essential Oil yields, content of essential Oil compounds (d-Carvone and its yield, α-phellandrene and linalool; except p-Cymene and Limonene in Isfahan population). Since in medicinal plants, the quantity (biological yield) and quality (essential Oil and d-Carvone; the most important ingredient and the highest amount of essential Oil in this experiment), 66.6% vermicompost + 33.3% urea in Varamin population, was the best treatment in the experiment. In addition an in the direction of human health and sustainable agriculture, it is possible to reduce 33% of chemical fertilizers application and pollution; however, in terms of other essential Oil contents (α-phellandrene, Linalool and p-Cymene), 100% vermicompost fertilizer treatment was superior in Isfahan population.