The shortage of freshwater resources and the increasing demand for water have highlighted the need for efficient wastewater treatment and water reuse. In this regard, industrial wastewater containing dyes requires effective treatment methods due to the presence of various dye compounds and other pollutants. Membrane processes, particularly nanofiltration, are considered promising options owing to their suitable separation performance, relatively low energy consumption, and lower environmental impact. However, challenges such as membrane fouling, flux decline, and the need to achieve both high separation efficiency and stable performance limit the application of conventional polymeric membranes. In the present study, a pristine polyethersulfone (PES) control membrane and mixed-matrix nanofiltration membranes containing graphene oxide (GO) and a silver-based metal–organic framework/graphene oxide nanocomposite (Ag-MOF@GO) were fabricated to improve membrane performance and enhance antifouling properties. First, mixed-matrix membranes containing 0.03, 0.05, 0.07, and 0.09 wt.% GO were fabricated, and their performance was evaluated in terms of water flux, fouling behavior, and dye rejection. Based on the results, the membrane containing 0.05 wt.% GO was selected as the optimal membrane at this stage. Subsequently, to investigate the effect of incorporating a silver-based metal–organic framework into graphene oxide, Ag-MOF@GO nanocomposites were synthesized using three ligand-to-silver mass ratios (1:0.5, 1:1, and 1:1.5). Mixed-matrix membranes containing 0.05 wt.% of each synthesized nanocomposite were then fabricated. The performance of the prepared membranes was evaluated in terms of pure-water flux, rejection of synthetic dyes, treatment of real wastewater, and fouling properties. Evaluation of the modified membranes revealed that the membrane containing 0.05 wt.% Ag-MOF@GO nanocomposite with a silver-to-ligand mass ratio of 1:1 exhibited better performance than the control membrane and the other nanocomposite-containing membranes and was therefore selected as the optimal membrane. The optimal membrane exhibited a lower water contact angle (54.2°) than the control membrane (77°), indicating enhanced surface hydrophilicity. Furthermore, pure-water flux increased from 18 to 50.1 kg m?² h?¹. The flux recovery ratio following fouling with bovine serum albumin (BSA) increased from 68.1% for the control membrane to 95.9% for the optimal membrane. The irreversible fouling resistance decreased from 31.8% for the control membrane to 4% for the optimal membrane. In addition, Congo red rejection increased from 97% to 99.3%, while methylene blue rejection increased from 91% to 97% for the control and optimal membranes, respectively. Finally, the performance of the selected membrane was evaluated using real industrial wastewater. The results showed that the optimal membrane achieved COD removal and color removal efficiencies of greater than 95% and 99.8%, respectively, and reduced turbidity to 2 NTU, compared with 52% COD removal, 96.7% color removal, and a turbidity of 7 NTU for the control membrane.    Keywords: Nanofiltration, polyethersulfone, graphene oxide, silver-based metal–organic framework, Ag-MOF@GO nanocomposite, membrane fouling, dye rejection, industrial wastewater.   

آنزيم‌ها يكي از مهم‌ترين دسته‌هاي پروتئيني در سامانه‌هاي زيستي به شمار مي‌روند و شناسايي درست عملكرد آن‌ها اهميت زيادي در حوزه‌هايي نظير زيست‌فناوري، مهندسي آنزيم، كشف دارو و زيست‌شناسي محاسباتي دارد. روش‌هاي آزمايشگاهي سنتي براي تعيين عملكرد پروتئين‌ها زمان‌بر و پرهزينه‌اند و توان پاسخگويي به حجم عظيم داده‌هاي پروتئيني كه اين روزها توليد مي‌شود را ندارند. از همين رو، روش‌هاي محاسباتي و مبتني بر هوش مصنوعي به گزينه‌اي جذاب براي پيش‌بيني سريع و در مقياس بزرگ عملكرد پروتئين‌ها تبديل شده‌اند. در اين پژوهش تلاش شده است مدلي هوشمند طراحي و توسعه داده شود كه بتواند صرفاً بر اساس توالي اسيدهاي آمينه، كلاس اصلي عملكردي هر آنزيم را پيش‌بيني كند.

   Abstract: Economic Load Dispatch (ELD) is one of the fundamental operational problems in power systems. Its objective is to determine the optimal power generation of generating units while minimizing fuel costs and satisfying operational constraints. In this study, a hybrid GWO-HPSO algorithm is developed to improve the balance between exploration and exploitation. To enhance the search capability of the proposed method, three mechanisms, including nonlinear inertia weight reduction, adaptive Cauchy mutation, and SQP-based local search, are incorporated into the algorithmic framework. The performance of the proposed method is evaluated on standard 3-, 13-, and 40-unit systems under various operating conditions, including the valve-point effect, transmission losses, and the Combined Economic and Emission Dispatch (CEED) problem. The results for the 40-unit system show that the improved algorithm achieves a best cost of $121,595.63/h and a mean cost of $122,584.98/h, outperforming PSO, GWO, and the original hybrid algorithm. Compared with the standard GWO algorithm, the proposed method achieves an approximately 1.744% reduction in the best cost. Furthermore, in a direct comparison with the WHOA algorithm reported in the reference study, the obtained cost is approximately 0.0165% lower. In the environmental analysis, emission coefficients are explicitly reported, while the actual generation cost and emissions are calculated independently. The CEED analysis indicates that moving from a purely economic operating condition to a condition with full environmental priority reduces emissions by approximately 14.98%, 87.88%, and 52.33% in the 3-, 13-, and 40-unit systems, respectively. The results demonstrate that the proposed method has a strong capability to solve non-convex, multimodal, and large-scale optimization problems and can provide an appropriate trade-off between economic and environmental objectives. Keywords Economic Load Dispatch (ELD); Hybrid Optimization; PSO-GWO; Multi-objective Optimization   

   Abstract The use of passive control systems, such as metallic yielding dampers, is an efficient solution for improving the seismic resilience of structures and concentrating damage in sacrificial fuse components. The present research investigates the numerical and analytical seismic behavior of three-branch U-shaped metallic dampers. In the first stage, a valid experimental specimen was validated in the Abaqus finite element software to ensure the accuracy of the modeling process, and the results showed good agreement between the numerical and experimental hysteresis curves. Subsequently, a parametric study was conducted on 81 numerical models with geometric variables including arc radius (70, 90, and 110 mm), thickness (15, 20, and 25 mm), and width (40, 60, and 80 mm) under loading angles of 0, 15, and 30 degrees. All models were subjected to displacement-controlled cyclic loading to extract performance indicators such as effective stiffness, ultimate strength, and energy dissipation capacity. The results of the analysis indicated that increasing the thickness and width of the plate has a direct relationship with increased stiffness and energy absorption, while increasing the arc radius leads to a decrease in these parameters. It was also found that changing the loading angle, particularly when combined with variations in section width, influences the area enclosed by the hysteresis curve. In the final part of the research, based on the extracted data, new analytical relationships were proposed to predict initial stiffness and yield displacement with high accuracy. The validation of these relationships with numerical data confirms their efficiency in estimating the mechanical characteristics of the damper without the need for complex analysis. Keywords: Three-branch metallic damper, Parametric study, Energy dissipation, Effective stiffness, Finite element modelingt:

Shear ductility of reinforced concrete beams, due to the sudden and brittle nature of shear failure, is one of the fundamental challenges in structural design. Despite extensive research, simultaneous investigation of the interaction among four key parameters, including concrete compressive strength, tensile reinforcement ratio, shear reinforcement ratio, and shear span to effective depth ratio, over a wide parametric range has received less attention. The aim of this study is to quantitatively and qualitatively evaluate the influence of these parameters on load carrying capacity and the shear ductility indices ?? and ??, and to develop accurate predictive models based on a data?driven approach. In this research, 1260 reinforced concrete beams were modeled using the nonlinear finite element method in ANSYS software. The Menetrey?Willam yield surface was employed to simulate the behavior of concrete, while an elastoplastic model with isotropic hardening and the Voce hardening law was used for the reinforcement. The design variables included five levels of concrete compressive strength, six levels of tensile reinforcement ratio, seven levels of shear reinforcement ratio, and six levels of shear span to effective depth ratio. The obtained data were analyzed using advanced machine learning and deep learning techniques, including neural networks. The results show that increasing the tensile reinforcement ratio has the greatest effect on increasing load carrying capacity, but significantly reduces ductility; at the minimum tensile reinforcement ratio, the ductility indices reach their highest values, while at the maximum and beyond, the ?? index approaches approximately 1. Shear reinforcement has no significant effect on ultimate capacity (about 3% increase) but is the most important factor for improving ductility; at the maximum shear reinforcement ratio, ?? increases by about 3% and ?? by about 8%. Increasing concrete compressive strength from normal to high-strength reduces ?? by about 13.4% and ?? by about 7.9%. The shear span to effective depth ratio has an inverse relationship with load carrying capacity and a direct relationship with ductility; at a ratio of 5 compared to 3, ?? increases by about 12.7% and ?? by about 6.2%. There is no direct linear relationship between load carrying capacity and ductility; the behavior of reinforced concrete beams is multi?parametric, and by optimally combining the design parameters, both adequate strength and ductility can be achieved simultaneously.

  In this study, the effects of various pretreatment methods on cellulase enzyme production from wheat straw using solid-state fermentation and the fungus *Trichoderma reesei* ATCC 26921 were investigated. Wheat straw, as a significant agricultural waste in Iran, has high potential for producing industrial enzymes and bio-products. The main objective was to find the optimal pretreatment method for maximizing cellulase production. Through Box-Behnken design, the best fermentation conditions were found at 30°C, 80% humidity, over 6 days. The study explored acidic, alkaline, combined, and deep eutectic solvent pretreatments, revealing that the deep eutectic solvent calcium carbonate-glycerol improved enzymatic activity by 38% compared to untreated samples. FTIR analysis showed enhanced lignin and hemicellulose degradation, improving cellulose accessibility. This research emphasizes sustainable development and optimal use of agricultural waste, offering new pathways for industrial enzyme production and reduced environmental pollution.

The design and construction of water wells are unfamiliar to many engineers. Due to this unfamiliarity, their design is often done inappropriately or completely ignored. In the mechanical design of ground source heat pump systems, we should be familiar with the terminology of water wells and key issues related to their construction. In wells, the still water level and the pumping level are two different states, and in case of low water or no water, sensors and automatic cut-offs can remove the float from the circuit. In this research, we have designed a circuit that differs from existing circuits in that the circuit we have designed can be adjusted at any water level.   

   The sharp decline in fossil fuels, as well as the increase in the emissions of harmful air pollutants and greenhouse gases from this burning, which also includes a large percentage of energy, have reduced the acceptance of these fuels. As a safe, renewable and non-toxic fuel, biodiesel is a good alternative to petroleum diesel. The study used cattle slaughterhouse fat waste as cheap raw materials to produce biodiesel fuel by homogeneous game Trans-sterification. From the design of experiments with the design expert software to the response level method (RSM) the effects related to temperature operating parameters, potassium hydroxide catalyst concentration and molecular ratio of methanol to oil were examined individually at three different levels. A total of 17 experiments were designed and conducted individually to investigate the effects of these parameters on reaction efficiency. The results obtained are confirmed by preparing the sample in the predicted conditions of the model. The highest yield related to the molecular ratio of methanol to oil was 6: 1, the catalyst concentration was 1.25% by weight of potassium hydroxide and the reaction temperature was 62 ° C with a reaction time of 1.5 hours of 8.97% by weight. There was a good match between the data from the experiments and the statistical model for the yield of biodiesel produced. The properties of biodiesel produced were determined by the quality in terms of fuel characteristics such as density, gravity, ignition point, sulfur value, humidity and combustion point, and were well matched by the use of EN and ASTM standards. The study shows that cattle slaughterhouse fat waste can be used as a raw material for the production of biodiesel by the Trans-sterification method with the catalyst of homogeneous play of potassium hydroxide and methanol solvent.

   One of the relatively accurate methods for determining the seismic response of structures is the use of inelastic dynamic time history analysis. Due to the time-consuming nature of this type of analysis, the large amount of calculations and the need for seismic engineering knowledge, the inelastic static analysis method (Pushover) has been the focus of civil engineers. In general, this analysis method can be >In this thesis, in order to examine the rules of regulations in the discussion of higher modes, three buildings with a special RC-Moment resisting frame system and with the number of floors from 15 to 21, which have an irregular plan, were selected and modeled for analysis and design in the environment of the ETABS program. Linear static and spectral dynamic analyzes were performed on the structures. Then, based on the criteria of Article 9 of the National Regulations of Iran and Iranian Standard 2800, they were designed for the area with high seismic risk and soil type 3. After the design, the structures were inelastically modeled in the SeismoStruct program environment, and inelastic dynamic analysis was performed under three pairs of record’s far from the fault and three pairs of record’s near the fault, which were scaled according to the 2800 standard criteria. Inelastic static analysis (Pushover) was also performed under three lateral load patterns of the first mode, triangular and spectral. The structural displacement responses were extracted and used to check the criteria. By examining and controlling the inter-story drift ratio of structures, it was observed that the first mode lateral load pattern, in estimating the maximum ratio of inter-story displacement of structures, has better accuracy than other lateral load patterns and is closer to the results of inelastic dynamic analysis, although there are differences. This model estimates the need to displacement structures in upper floors more than other models. In the lower floors of structures, the triangular lateral load pattern estimates the need for displacement more than other patterns. Regarding the distribution pattern of inter-story displacement ratio, it seems that the main problem and the biggest difference is in the lower floors of the structures. However, it is concluded that the criteria of standard 2800 are justified in the discussion of pushover analysis and the effect of higher modes, and it is better to use inelastic dynamic analysis if the effect of higher modes dominates the structure.

In this research, biological plasticizer   were made based on edible oil waste using epoxidation and esterification reactions. The purpose of this study is to evaluate the effects of adding these bioplasticizers in PVC as a plasticizer and compare its properties with dioctyl phthalate (petroleum-based plasticizer). In this evaluation, FTIR, TGA, DSC analyses, brittleness test during stretching, hardness testing, and migration and fugacity resistance testing were performed. By performing the TGA test, it was found that the PVC sample synthesized with our bioplasticizer has a higher degradation temperature, which means more heat resistance compared to other samples. The tensile test analysis showed that the PVC produced with bioplasticizer in Compared with dioctyl phthalate, it has good tensile stability and the failure graph during stretching was close to the graph of dioctyl phthalate, which results showed that it has almost the same behavior as dioctyl phthalate and this softener can improve the flexibility of PVC.Then, by examining the dissolution of different synthesized samples in different solvents (polar and non-polar), we came to the conclusion that the reduction in the mass of the sample synthesized with this biological softener in non-polar solvents was significantly less and more stable, but in Polar solvents were more reducing the mass of the sample due to the polar structure of the bioplasticizer. Also, compared to other samples, it showed lower volatility and higher thermal stability in the volatility test.

  Heavy metal pollution is one of the concerns that has become a global concern, and cadmium is one of the types of metals that are very dangerous and carcinogenic. Bioremediation is one of the environmentally friendly methods that is a suitable alternative to chemical methods. Biomineralization is one of its subcategories, which is a process during which microorganisms make mineral from the biological mineral environment and eliminate its risk.The aim of this research is to work on the biological mineralization process and test this process in the bacterial culture environment.The microorganism used is Bacillus persicus and the desired metal is cadmium, which by preparing the required solid and liquid culture medium, the defined process for three operational parameters: pH (6.5-8.5), temperature (25-35°C) and the concentration is 1500-200 ppm.The findings indicate that the highest removal rate is 57.17%. In relation to pH, the process of removal increased gradually with the increase of pH from 6.5 to 8.5 and we reached the maximum amount of removal at 8.5. In relation to the temperature, with the increase in temperature from 25 to 35 degrees, the removal status is increasing, and then from 35 to 45 degrees, we have seen a decrease in the amount of removal, and at 45 degrees, we have had the minimum amount of removal. Also, in relation to the concentration, we have seen an increase in the removal rate by increasing the concentration from 200 to about 1240, and after that, a slight decrease has occurred up to the concentration of 1500.The simultaneous state of pH and concentration had the greatest effect on the amount of removal, followed by temperature, concentration and pH respectively.

Connections in precaststructures are of great importance and their design requires great precision totransfer lateral loads such as earthquakes and wind. On the other hand, everyyear, a large number of buildings catch fire and cause a lot of financial andhuman losses. In other words, fire in buildings is one of the serious threatsto the life and financial security of society. Therefore, the necessity ofresearch related to connections in precast structures and the importance ofstudying their behavior after fire is felt more than ever.The resistance ofstructural members against fire is one of the important parameters for having asafe building. Buildings of medium importance and high importance should bestable for at least 90 minutes in fire. Based on this, many researchers havestudied the behavior of beam-to-column connections after fire, but none of themhave investigated the behavior of precast concrete beam-to-column connectionswith metal-yielding dampers under the effect of fire with different diversions.Have not given so, this research is an attempt to fill this scientific gap,that if we have a metal-yielding damper in the connection of the prefabricatedbeam to the column, what is the effect of fire duration on its post-firebehavior?Therefore, in thisresearch, the first goal is to propose a new beam-to-column connection with ametal-yield damper in precast structures, and the second goal is to provide amethod to protect it against fire. The third goal, which is the main goal ofthis research, is to investigate the effect of duration of exposure to fire onits behavior.For this purpose, firstthe new articles were studied and then validation was done in ABAQUS software,and in the next step, several precast beam-to-column connections withmetal-yield dampers were analyzed, and one of them, which had better hysteresisbehavior, was selected to continue this research. In the next step, accordingto past studies, the use of concrete cover was used to protect the connectionin fire conditions. In the next step, after performing the heat transferanalysis, the mechanical analysis was performed. Finally, resistance afterfire, stiffness after fire, heat distribution were discussed in numericalmodels.The results of hysteresisanalysis of beam-to-column connection in pre-fire conditions show that theproposed beam-to-column connection has good seismic behavior. Also, afterthermal analysis and based on TEMP contour, in numerical models with 10 cmthick concrete cover, increasing the duration of the fire from 60 to 120minutes has caused more fire heat to reach the beam-to-column connection, asthe temperature of the coldest connection point of the beam to the column is about237 degrees Celsius in the 60 minute diversion, and in the 120 minutediversion, the temperature of the coldest connection point of the beam to thecolumn is about 394 degrees Celsius.Also, this research showsthat placing the beam-to-column connection exposed to fire with deflection of60, 90, and 120 minutes, on average, reduces the bending moment by 40, 50, and60 percent, respectively, and reduces the bending stiffness, respectively, byThe value is 39, 47 and 65 percent.  

  Color is one of the most important quality properties of the product that is first visible to the consumer. Color is an effective factor in attracting attention and selecting the food that is received through the sense of sight, and its presence in the rapid diagnosis and final acceptance of each product will be due to its attractiveness. According to the FDA (Food and Drug Administration) definition, food coloring is: "A color additive contains any dye, pigment, or other substance made by a synthetic process or similar method, or from a plant, animal, "Minerals and other sources or intermediates have been extracted, isolated and derived, and when used for food, medicine, cosmetics or any other part, can create and add color to it." Which will be added to food, beverages and cosmetics for human consumption in order to create color. According to this definition, colors are divided into two categories: licensed for consumption (ie, for food consumption, a license is required, such as dyes of natural origin) and non-licensed for consumption (ie, it is not necessary to obtain a license for consumption). Fabrics and carpets are used) are divided. With the passage of time and the increasing need of various cosmetic, health, textile, food, etc. industries for more and more diverse colors, humans began to prepare and mass-produce dyes in an industrial way, the production and consumption of which in non-food industries caused Air pollution, groundwater aquifers, running water, pollution of agricultural lands and pastures in the food, cosmetics and health industries have caused deep concern about the safety of chemical or synthetic dyes in the health of the body (1). Due to the allergic effects of some artificial colors in foods such as azerobin or tartrazine, their use in various food industries is limited (8). Some synthetic dyes also show carcinogenic and mutagenic effects, for example dye used in the meat industry to form nitrosamines. This substance combines with nitrate and nitrite to form an amino agent (9) in order to To counteract these harmful effects, there is a global trend towards the production of pigments from natural sources. Natural dyes are derived from two important sources of plants and microorganisms. In the meantime, dyes derived from fungal sources have wide and very important applications in the nutrition and economy of human society and are able to create a profit of about $ 30 billion per year in the industrial process. The number of different colors in fungi is more than a thousand species that are not found in other organisms or are very small (1). Permissible edible and natural pigments of plant origin will cause many problems such as instability against light, heat, low or high acidity, low solubility and often lack of easy access throughout the year (2).

 the aim of this study was to investigate liquid-liquid equilibria for 2-propanol+ trisodium citrate/ sodium acetate/ sodium potassium tartrate + water systems at room temperature and different pH values ( 5,6,7/6,8/6/9/30/10/25) . the binodal curves of these systems were measured and compared at the mentioned pHs. accordinglyU experimental binodal data were correlated using MerchukU Hu and Pirdashti equations. as a resultU for all three equations R2 value was greater than 0/99 which shows a good correlation of bindol data. Hu equation model with lower RMSE value had optimal condition for binodal data fitting. Tie-line compositions were correlated by Othmer-Tobias and Bancroft equations. R2 value was greater than 0/99 for both equations. In addition, the effect of pH, salt and alcohol type on phase separation ability was studied. According to the results, an increase in pH value, hydrophobicity of salt and alcohol carbon number at room temperature leads to an expansion of biphasic region and approaching the binodal curve to the origin. on the other handU it was observed that kosmotropic ions with higher surface charge density and lower solubility in water are able to form a wider biphasic region.

   Abstract In resent years, FRP composites have broadly and successfully been used to improve seismic behavior of the structures. Great resistance of these materials against erosion together with the high ratio of strength to weight in these materials are the reasons why strengthening the structure by using these materials do not impose extra weight to the structure, unlike the traditional methods in which shotcrete or ferrocement are used. Beam-column connections in reinforced concrete moment frames are critical points in performance of reinforced concrete moment frame during the earthquake. Many studies have done on reinforcement of beam-column connections in reinforced concrete frames using FRP materials. Most of these studies are done in micro scale on shear strength and ductility of connection, and some solution are provided for its improvement, and little studies have done on seismic parameters such as behavior factor of reinforced concrete frame, the amount of energy absorption, and loading and displacement capacity of the frame reinforced with FRP in connection point in macro scale. In this thesis to numerically investigate the behavior of beam-column connection in reinforced concrete buildings in macro scale using finite element theorem, and some solutions are recommended for reinforcing and improving their seismic performance using FRP composites. In contrast of experimental samples which have many constrains for observing and obtaining results, in finite element modeling, these constrains are fewer, and it is easier to model a sample nearer to reality.   

Numerical Study of Magnetic Field Effect on Convection Heat Transfer of Nanofluid Flow in a Microchannel  

  Abstract Early agricultural production of lignocellulose, available at a significant quantity and low cost, can be an additional source of income for farmers without adversely affecting the fertility of the soil for industrial applications. Wheat straw is one of the most abundant agricultural lignocellulosic biomass, partly Organic Wheat Plant. Wheat straw is used after harvest as a feed for livestock and in cattle-breeding buildings, as well as a large amount of it is burned, while it contains high amounts of cellulose and It can be used as an inexpensive early raw material for the production of valuable cellulose derivatives. In this research, the possibility of producing valuable carboxy methyl cellulose material was investigated using cellulose extracted from wheat straw. Wheat straw contains approximately 33-40% cellulose, which together with hemicellulose and lignin make up its main components. In this research, cellulose in wheat straw was first extracted by sodium hydroxide 10% w / w and sodium hypochloride in two stages. The extracted cellulose was converted to Carboxy methyl cellulose using the Williamson ether process, which the FTIR spectrophotometry used to identify the substituted carboxy methyl groups on the cellulose. The degree of substitution (DS) is the most important factor influencing the solubility and application of carboxy methyl cellulose, and its production efficiency is an important factor in the economic process of production, so the etherification process over operating factors, including: a weight ratio of monochloroacetic acid to cellulose, the concentration of sodium hydroxide, the temperature and reaction time were, at three levels (1, 1.4, 1.8), (20, 30, 40% w / w), (30, 50, 70 ° C) and (1, 3, 5 hours) were optimized with design expert software called MODDE by CCF method using response surface methodology in order to achieve the highest DS and an economical efficiency. The optimization results showed that at a weight ratio of monochloroacetic acid to cellulose 1.3 to 1, the concentration of sodium hydroxide was 20% w / w, temperature 70 ° C and reaction time 1 hour, obtained the highest degree of substitution   0.975 and the yield under these conditions was 1.37 g CMC / g cellulose. Keywords: Wheat straw, Cellulose, design expert software, Carboxy methyl cellulose, Degree of substitution   

طراحي و ساخت ماشين نورد نامتقارن ورق هاي فلزي

In recent years, widespread use of synthetic plastics has led to an increase in the volume of non-degradable waste and environmental pollution. To cope with this problem, researchers have sought to find a suitable alternative to these materials. Biopolymers are materials that come from renewable sources and are completely degraded in the environment, and thus can be a promising alternative to synthetic plastics. Polyhydroxybutyrate (PHB) is the most famous member of the family of polyhydroxyalkanates (PHA), which is produced in the context of nutrient restriction as a source of carbon and energy as granules in the cytoplasm of some bacteria.In this research, a biopolymer producing bacterium was isolated from rhizosphere soils of oak forests of norabad, located in Lorestan province. The use of various carbon sources such as glucose, glycyrrone and rice shell extract separately and in combination for the growth of microorganisms and PHB production was investigated. In order to optimize the production of biopolymer, the method of designing experiments CCD with five factors (temperature, carbon content, C/N ratio , Extract amount ) was used in three levels. To identify and validate the   PHB, the Fourier Transform Infrared   (FTIR), Gas Chromatography- Mass spectrometry(GC-MS)   and Nuclear Magnetic Resonance spectroscopy (NMR) were performed. The maximum efficiency of PH   production in this study was obtained at 35 ° C, pH = 5, 20 g / l of carbon source, C / N : 4 and the amount of rice shell extract of 150 ml per liter of medium. Maximum cell dry weight (CDW), PHB content and production efficiency were obtained in 3000 mg / l, 1870 mg / l and 63.5% respectively.

  Recently with respect to the environmental problem caused by synthetic polymer, more consideration was attentive on biopolymer. Among the biopolymers, polyhydroxyalkanoate (PHA) get more attentions due to their properties such as environmental friendly and biodegradability. Many microorganism are able to produce and accumulate PHA in their cells. In this research the bacteria was isolated from Roodbar olive and Dallahoo oak forest soils. Between the isolated bacteria, one of them which was able to produce and accumulate more PHA was selected. Glucose and glycerol used as carbon sources, while wheat straw extract used as an additive carbon source. FT-IR, HNMR and GC-mass analysis confirmed that produced biopolymer was polyhydroxybutyrate-co- hydroxylvalerate with 19.92% valarate. Experimental design with 5 factors (carbon source amount, C/N, pH, temperature and extract amount) at 3 levels were used to model and optimized the biopolymer production. The optimum condition was 25 g/l of carbon, ratio of C/N of 10, pH=9, T=34 °C, Extract = 300 ml/l.In this condition the produced biopolymer amount was 2620 mg/l. SEM Image confirm the nanosize of nanoparticles in polyhydroxyalkanoate-cellulose nanocomposite with average size of 80 nm.   

<  gt;پيش بيني وقوع عيوب مركزي در فرآيند اكستروژن ميله</P>

مدلسازي تحليلي بار ضربه اي سرعت پايين روي صفحات ساندويچي مدور گلار – فوم

  AbstractIn this study, it was investigated the use of nano-silica heterogeneous catalyst in biodiesel production from canola oil. This catalyst was synthesized from wheat bran during acidic processing under controlled conditions. Wheat bran is an agriculture by-product which its burning is accompanied by environmental pollutants. This by-product contains high much amorph silica. Acidic processing of wheat bran and then thermal treating under controlled conditions in 700 C caused to nano-silica production with high area and with amorph structure. Nano-silica had high amount acidic sites. XRD analysis approved the synthesized nano-silica structure. The results for SEM showed that particles had spherical structure, regular and homogenous. The effects of four parameters including reaction temperature, catalyst concentration, molar ratio of methanol/oil and reaction time on biodiesel conversion was evaluated by response surface method. Molar ratio of methanol/oil was 99.01% under optimum conditions including 70 C, 3% catalyst weight and for 5 hours. The data for catalyst recovery showed that the prepared catalyst has renewability for 5 times which can be used as sustainable and economical catalyst for biodiesel production. Key words: wheat bran, nanosilica, biodiesel, canola oil, RSM optimization       

High-value chemical production using nanostructure catalysts

  In this thesis two new compact size high selective microstrip bandpass filters for X- and Ku-band are proposed. The presented structure uses T-shaped resonators with direct connected orthogonal feed lines. The T-shaped resonator provides high selectivity for the proposed filter and reduces the overall size of the filter, compared with conventional uniform stub. Due to its symmetrical structures, it can be analysed with the odd and even mode. Two filters at X- and Ku-band, respectively with fractional bandwidth of 30.3 % and 37 % were realized on a Roger 5880 substrate with dielectric constant of 2.2 and 15mil thickness. Simulation and experimental results demonstrate good agreement.