In this research diacetyl production as a buttery flavor in food industries by Lactic Acid Bacteria (LAB), Lactococcus and Leuconostoc genus was investigated. Batch fermentation process accomplished on MRS (De Man, Rogosa and Sharpe medium) broth medium, medium based on whey powder and based on skim milk powder at different conditions of temperature, agitation speed, glucose as carbon source, tri-sodium citrate as precursor of diacetyl production, inoculum, catalase enzyme, bovin blood as heme protein source and CuCl2. Optimum conditions were determined for achivement of highest production yield. This research indicated that the optimum fermentation conditions for diacetyl production by LAB were: 32oC, 180 rpm, glucose 6 g/l, tri-sodium citrate 5g/l, inoculun 5%, catalase enzyme 6 ml/l, bovin blood 4 g/l, CuCl2 15 mg/l. Finally, for production of diacetyl, a fermenter was used with 10 liter volume, inoculum size 5% (v/v) with working volume of 6.5 liters. Agitation and temprature were maintained at 180 rpm and 320C, respectively. Diacetyl concentration under optimized condition in fermenter was obtained as 945 mg/l.

Biodesulfurization of coal has been carried out in batch culture of single strain and mixed culture of sulfur oxidizing bacteria. The pure cultures of Thiobacillus thiooxidans and Thiobacillus ferrooxidans utilized inorganic sulfur content of Malaysian coal. The chemolithotroph bacteria were able to grow on coal and metabolize the coal's sulfur content. The batch cultures of coal with 3-5 percent sulfur were used for growing microorganisms. A few species of bacteria and fungi had potential to utilize coal complex media, which were isolated from coal rice hulls and pharmaceutical wastewater. Asperigillus niger and Thiobacillus species isolated from coal, fungi from rice hulls and Saccharomyces species from wastewater, all microorganisms capable to grow on coal. The main concern was the sulfur oxidizing bacteria were screened out from all non-sulfur reducing bacteria. In the Batch cultures, the biooxidation coal's sulfur was affected by several parameters, such as pH, nutrients, agitation rate, growth stimulants and percentage coal. The trace amount of magnesium and cobalt ions, 200 rpm agitation rate with initial pH of2.6 for mixed culture of Thiobacillus thiooxidans and Thiobacillus ferrooxidans showed maximum growth rate and optimum batch operating conditions. The highest sulfur oxidation was obtained at the optimal Thiobacillus growth rate. Morethan 75 percent of sulfur was removed from coal. The biooxidation of coal, the kinetic model followed by Monod rate equation with specific growth rate,  mmax= 4.8 d-1 and rate constant, Ks = 16.7 g/L.

The biodegradation of Cypermethrin (20 to 125 mg/L) in effluent using batch activated sludge was studied. Degradation was found to occur to a great extent only in the presence of Pseudomonas (IES-Ps-1) culture. Under aerobic conditions using mechanical aerators, Cypermethrin (20 mg/L) was almost completely degraded in just over 48 h at ambient temperature. Further loading of organic compound in subsequent experiments demonstrated that IES-PS-1was capable to degrade 82 % Cypermethrin at 40 mg/L dose in approximately 48 h. When the concentration was increased to 80 mg/L, 50% degradation of this compound was observed. Over this time period the cells could utilize only 17 % of Cypermethrin when it was given 125 mg/L, respectively. These findings indicate that increased concentration of Cypermethrin has a marked effect on biodegradation performance of IES-Ps-1 with a modest increased in the duration of lag phase, but did not lead to complete inhibition or cell death. These results proved that IES-Ps-1 is responsible for Cypermethrin degradation. Such finding may be useful in designing a scale-up in situ or on-site hazardous waste bioremediation process for field application.      

Background and Objective: Considering the importance of environmental protection and necessity of using new energy sources and innovative fuels, using of renewable energies have been a great concern. Due to this necessity, in this study, mathematical modeling and simulation of a batch bioreactor to produce methane from livestock waste was investigated numerically. Method: The relationship between microorganism’ s growth rate and substrate concentration were established by Monod model. The equations of mathematical model were solved with fourth order Rung Kutta. The effect of initial microorganisms’ concentration on methane production was also investigated. Initial concentration of substrate and microorganisms are 51. 74 g/L and 1. 61 g/L, respectively. Findings: The results revealed that the mathematical model average deviation from experimental data is 8. 53%. The amount of methane produced after 70 days is equal to 10. 29 g/L. The substrate disintegration and methane production are a function of substrate retention time. Enhancement in the initial concentration of microorganisms causes methane gas production in less time. The amount of methane gas produced is independent of initial microorganisms’ concentration. Discussion and Conclusion: The model which presented in this study could be used to predict the time required to carry out the reaction, ooptimum performance of bioreactor, the relevant process equipment design, scale up of equipment such as digestive and appropriate control of operation to produce high-purity methane and higher volume of biogas in the bioreactor.

Mathematical modeling and simulation of microbial Polyhydroxybutyrate (PHB) production process is beneficial for optimization, design, and control purposes. In this study a batch model developed by Mulchandani et al., [1] was used to simulate the process in MATLAB environment. It was revealed that the kinetic model parameters were estimated off the optimal or at a local optimal point. Therefore, an optimization program was written using AM TLAB codes to estimate those parameters again. It resulted in a significant improvement in the accuracy of Mulchandanis kinetic model. The batch model was evaluated using two batch experiments performed in this work and also Mulchandanis batch data when kinetic model parameter values estimated in this work were used. Visual comparisons between the model profiles and experimental data indicate that the model represents the process reasonably. A goodness of fit criterion used in this work and some similar researches proved higher accuracy of Mulchandanis model using this works kinetic parameter values compared to other models. Theoretical model verification was also performed that lead to identification of the possible limitations of the model.

How to profoundly change the beliefs of the polytheists during the age of revelation from the denial of the Prophet (pbuh) to the certainty of his Message and the acceptance of his full guardianship is a question worthy of attention. The order of verses about prophecy based on the order of revelation is the reason to lead a transformative process and a special Quranic method in institutionalizing the belief of prophecy in the lives of Arabs. In the first stage, the Holy Quran in the first Makkī (Arabic: المکّیّ, suras revealed in Mecca) chapters has prepared the community from the motivational side to accept the truth of the Prophet’s (pbuh) prophecy and briefly stating the key issues surrounding it. The Holy Book of Quran at the time of the emergence of oppositions and doubts (the second stage) destroyed the arguments of the polytheists and explained the prophecy and proved its authenticity from a cognitive perspective in the second stage by presenting clear arguments. and the Holy Book of Quran in the third stage after Madanī (Arabic: المدنیّ, suras revealed in Medina) period has undertaken measures in order to fulfill the goals of the Massage by explaining the true position of the Prophet (pbuh) to deepen and operationalize the Prophetic belief through explaining practical duties for the Prophet (pbuh) and behavior based on the acceptance of Walaya (Arabic: ولایة, meaning “guardianship” or “governance”).

Backgrounds and Objectives: Direct biodegradation of landfill leachate is too difficult because of high concentrations of COD and NH3 and also the presence of toxic compounds. The main objective of this study was to application of Strurvite precipitation as a pretreatment stage, in order to remove inhibitors of biodegradation before the batch decant activated sludge process with addition of powdered activated carbon (PAC).Materials and Methods: Strurvite precipitated leachate was introduced to a bench scale batch decant activated sludge reactor with hydraulic retention times of 6 and 12 hour. PAC was added to aeration tank directly at the rate of 3.5 g/L.Results: TCOD, SCOD, NH3 and P removal efficiency with addition of PAC in HRT of 6 h were 90, 87, 98.3 and 94 % respectively and 96, 95, 99.2 and 98.7 5 in HRT of 12 h.Conclusion: According to obtained data from this work, it can be concluded that Strurvite precipitation before batch decant activated sludge process and simultaneous addition of PAC is promising technology for leachate treatment and can meet effluent standards for discharge to the receiving waters.

Open-celled foams are capable to allow the passage of fluids through their structure, because of interconnections between the open cells or bubbles and therefore these structures can be used as a membrane and filter. In this work, we have studied the production of polystyrene open-celled microcellular foam by using CO2 as blowing agent. To achieve such structures, it is necessary to control the stages of growth in such a way that the cells would connect to each other through the pores without any coalescence. The required processing condition to achieve open-celled structures is predictable by a model theory of opened-cell. This model suggests that at least a 130 bar saturation pressure and foaming time between 9 and 58 s are required for this system. The temperature range has been selected for to be both higher than polymer glass transition temperature and facilitating the foaming process. Experimental results in the batch foaming process has verified the model quite well. The SEM and mercury porousimetry tests show the presence of pores between the cells with open-celled structure. Experimental results show that by increasing the saturation pressure and the foaming temperature, there is a drop in the time required for open-celled structure formation. A 130 bar saturation pressure, 150o C foaming temperature and 60 s foaming time, suggest the attainment of open-celled microcellular foam based on polystyrene/CO2 system in the batch process

This paper deals with batch process control in presence of unmodeled dynamics. An estimator is designed to estimate unmodeled dynamics without need of output differentiation and then, a Global Linearized Control (GLC) law is developed. The overall controller-estimator shows a good behavior against various disturbances and uncertainties in the process as well as unmodeled dynamics.