Introduction: Kojic acid with the chemical structure of 5-hydroxy-2-hydroxymethyl-ˠ-Piron is an organic acid that is biologically produced through aerobic fermentation process by using various substrates and via the function of variety of fungi. This study was aimed to study the optimization of Kojic acid production by Locally Isolated Fungi Aspergillus sp., using ‘Response surface Methodology’.Materials and Methods: Kojic acid was produced by fermentation of isolated strain of genus Aspergillus in submerged culture medium. Initial investigation in Kojic acid production process was performed via Plackett-Burman method and by using different nitrogen sources such as yeast extract, peptone, ammonium sulfate, ammonium chloride, urea as well as different carbon sources, including fructose, sucrose, glucose, lactose and maltose.Results: Based on our study, peptone and glucose were the most effective factors with carbon and nitrogen sources in production of kojic acid (P<0.05). The next step was production of 34.4g/L kojic acid by optimizing the effect of environmental factors such as temperature, pH, glucose and peptones, such as carbon and nitrogen sources, used in production of kojic acid and by employing ‘Response surface Methodology’.Conclusion: Based on the results of this study, the maximum production of kojic acid can be achieved by using; glucose (%8.71), peptone (37.4%), temperature (29.9oC) and adjusting pH to 6.75 in the production process.

Introduction: Micropropagation is important for both multiplication and preservation of a wide range of nursery plants, including many fruit crops. A number of studies exist on optimization of growth in in vitro condition for one or two cultivars, but often these results cannot be used for the other genotypes because individual cultivars may differ greatly in their requirements. Therefore, genotype-specific medium are usually empirically developed for many plants including pear. Pear cultivars and species are often recalcitrant to tissue culture manipulations and Murashige and Skoog (23) (MS) basal nutrient medium at full or half strength or with slight modifications is the most media were used. The QL, DKW, and WPM media are also used and they differ mostly in types or amounts of calcium and nitrogen in compared with MS. Developing growth media for specific and unique cultivars is complex and time-consuming. Currently, improved experimental design and using statistical softwares allow much more efficient approaches to be utilized for the improvement of micropropagation media and conditions. Improving of growth medium for in vitro propagation of plants depends on type and quantities of mineral nutrients and plant growth regulators as important ones. The existence of statistical softwares to manage effective factors is very needed to access an optimized growth medium for in vitro propagation of plants. Design Expert is used as auxiliary software to identify essential factors in in vitro culture. Since the in vitro proliferation parameters of Pyrus communis cv. ʽ Shekariʼ need to optimize for growth better, we were designed and performed a multifactor surface Response experiment by Design Expert software to following two goals. First, to find optimized amount of some elements in medium and second, to show the Response surface method can be useful for improving in vitro culture. Materials and Methods: One experiment was designed by Design Expert software and was performed to improve in vitro proliferated shoots of Pyrus communis cv. ʽ Shekariʼ . Shoots were grown in a modified MS medium (supplement with 1 mg l-1 of N6-benzyladenine) were used for this experiment. The experiment was included 20 model points randomly based on three nutritional factors: NH4NO3 (0. 5-1. 5×), Fe (0. 5-1. 5×) and micro nutrients (1-2×) in different concentration of their MS amounts. Media enriched with sucrose (30 g l-1) and agar (8 g l-1) after pH adjustment at 5. 7. Cultures were grown at 25° C under a 16-h photoperiod with 70– 90 μ M m-2 s-1 irradiance provided by a combination of cool-and warm-white fluorescent bulbs and were transferred to new medium every 3 weeks. Several Responses were recorded after two months: Proliferated shoot number, proliferated shoot length (cm), total leaf number, leaf chlorophyll a (mg g-1), leaf carotenoids (mg g-1), and vegetative growth (cm). Responses for each point were the mean of 5 replicates. Experimental design, model evaluation, and analysis were done by Design-Expert® 8 (2010) software and the highest-order polynomial model that was significant for each Response was used for ANOVA. Results and Discussion: Factors statistically were significant for Responses according to ANOVA in linear, 2FI and quadratic models. Reduced NH4NO3 (×0. 5) and enhanced Fe (×1. 5) induced the higher number of proliferated shoots up to 4. 43 folds of control according a quadratic model. NH4NO3 and Fe×Micro had negative liner relationships with shoot length, while leaf number negatively was affected by micros. Fe and NH4NO3 were effective factors on leaf chlorophyll a and carotenoids contents. Increasing Fe (×1. 5) and decreasing NH4NO3 (×0. 5) led to 2 folds higher production of chlorophyll a and carotenoids. Vegetative growth of Pyrus communis cv. ʽ Shekariʼ in a quadratic-order method (negatively controlled by NH4NO3 and micros) increased by high values of proliferated shoot number and shoot length induced by reduced NH4NO3 (×0. 5). Optimized amount of three studied factors based on two important Responses, maximum amount of proliferated shoot number and length, were 0. 9, 1 and 0. 5× for Fe, micro and NH4NO3 in MS medium, respectively. Conclusions: Design Expert software and Response surface method were used successfully for in vitro optimizing of Pyrus communis cv. ʽ Shekariʼ regenerated shoots. Fe, Micro and NH4NO3, were the effective factors for shoot regeneration Responses in linear, 2FI and quadratic models. The multifactor investigation in surface Response design will enable us to predict an optimal medium for several effective factors and estimate suitable Responses. Outputs of these types of experiments provide a suitable background to increase optimization accuracy for future experiments.

Zeolite were formed through agar gelcasting method.Response surface methodology ( RSM ) is proposed as a tool for rapidly optimizing the activation parameters in order to obtain the highest porosity of samples. 40 % of zeolite and 1 wt %  of agar was selected as optimal conditions. porous bodies with an optimal combination of 54.4% porosity , density 0.9 g / cm3 , and compressive strength of 6.67MPa  were made and observed that there is a slight difference between predicted values by the software and the measured values.  Longer time to mixing from 1 / 5 min to 3 min , the porous body has 67.17 % porosity , density 0.69 g / cm3 , and compressive strength of 5 / 3 MPa .XRD and SEM analysis was used to investigate the phase and structural changes at 800 C. The highest percentage of adsorption of methylene blue at 4ppm concentration after 72 h was 98.94 %.

In this research, in order to separate germanium from an aqueous solution containing tartaric acid, liquid-liquid extraction (LLX) and supported liquid membrane (SLM) were employed. In these systems, polytetrafluoroethylene (PTFE) as the membrane and Alamine 336 as the carrier/extractant were used. In the LLX system, the effect of concentrations of extractant, tartaric acid, and HCl as a strippant was studied. As a result, the germanium extraction efficiency increased 100% after reaching Alamine 336 concentration to 10 %v/v. At the tartaric acid concentration of 0. 275 mM, the highest germanium extraction (98. 6%) was obtained. According to the SLM experiments, the carrier concentration of 15 %v/v was enough for the efficient transport of germanium from feed to strip phase. In comparison with LLX system, despite transportation of all germanium species in the SLM system, the time of this process (20 h) is higher than that of the LLX system.

In this paper, a novel structure of a axial flux switching machines for use in wind speed turbines at low speeds has been proposed, which in addition to the previous advantages, has a simple and economical design for the production of this type of machines. In this proposed machine, the magnets are placed on the surface of stator, and the three-phase winding is located in the space between the magnets. After designing according to the criteria like increasing electromotive force, reducing the cogging torque and reducing the total harmonic distortion, using the design of experiments and the surface Response method combined with the finite element software, the appropriate dimensions are selected and the machine is optimized. To test the design accuracy, a prototype model is also made.

Background and Aims: When composite resin polymerizes, shrinkage stresses tend to produce gaps at the tooth/ restoration interfaces. surface sealants may reduce or avoid problems related to the marginal interface. The aim of this study was to evaluate the effect of two different surface sealants (Fortify and Optiguard) on the microleakage of class V resin composite restorations.Materials and Methods: Twenty three sound noncarious molars were collected. Totally, 45 Class V cavities with the occlusal margins in enamel and cervical margins in cementum were prepared in both buccal and lingual surfaces. The specimens were randomly assigned in three groups (15 cavities in each group) and then restored with a resin composite. After the finishing and polishing procedures, the restorations in each group were covered with a specific surface sealant, except for the control samples, which were not sealed. After placing restorations, the specimens were thermocycled and then immersed in a 50% silver nitrate solution (tracer agent) for four hours, sectioned longitudinally and analyzed for leakage using a stereomicroscope in a blind manner. The marginal microleakage was evaluated at the occlusal and cervical interfaces and compared among the three groups using the Kruskall-Wallis and the Mann-Whitney U tests.Results: Microleakage was found in all groups at both occlusal and cervical margins. Significantly greater leakage was observed at the cervical margins compared to the enamel margins of the material groups (P=0.005).There was no statistically significant difference among the groups at occlusal margins (P=0.66). In the cervical region, Fortify showed improved results and statistically presented the lowest degree of microleakage (P=0.003).Conclusion: The used sealant materials presented different rates of effectiveness and Fortify decreased marginal microleakage significantly.

The automobile workshop queue system has been optimized using various approaches, such as queuing theory, simulation, and probability. The utilization of Response surface methodology (RSM) for optimizing automobile workshop queue systems is not yet established. The utilization of RSM with direct observation enables the detection of patterns of correlations between variables and Responses, which are then represented through mathematical equations. The optimization process involves numerous factors that impact queue performance, which can be categorized into two parts. The number of servers, number of phases, number of workers, worker experience, and layout are classified in inner design. This study examines the relationship between two components of the outer design, specifically the arrival rate and the interarrival time. The Responses analyzed are queue cost, service time, average customer waiting time, and number of customers. The findings indicate that queue costs are not reliable for establishing the optimum value due to the significant impact of the cost structure on the structure of the optimal location. This study discovered that the number of leaving customers is related to queue costs and is relevant in selecting the optimal point. This study also formulates mathematical equations for predicting the optimal point. This study emphasizes the necessity for further investigation to uncover alternative mathematical equations that can precisely predict the optimal conditions for various types of services.

Laser surface hardening is one of the modern technology used to improve the surface of materials in order to modification of tribological properties. This paper investigate the ability of laser surface hardening of AISI 410 martensitic stainless steel using a continuous high power diode laser with a maximum power of 1600w. Laser power, scanning speed and focal plane position are variable parameters in this research. The effect of the process parameters on the hardness, depth and width of the hardened layer has been investigated. The results show that with increasing laser power and reducing the scanning speed, higher hardness and hardening depth are obtained. Results also reveal that width of hardened layer increases by increasing in focal plane position and reduction the laser power. Modeling of controllable variables (laser power, scanning speed and focal plane position) by Response surface Methodology method to study the effect of process input parameters on how to change Responses, and analysis of ANOVA tables, providing regression equation for output parameters, analysis The surface Plots, Interaction Plots of the input parameters, were investigated. The results show that in RSM modeling method, the effect of laser power parameter on the results of maximum hardness, depth and width of hardness is more than the parameters of the focal plane position and scanning speed. Due to percentage of coverage of the parameters by the regression equations the RSM method is a suitable model for investigating the effects of the surface hardening process by diode laser.