Iranian Journal of Chemistry and Chemical Engineering
Volume:42 Issue: 5, May 2023

In this work, an easy method was employed to successfully develop La3+-doped ZnO nanoflowers and Guar-Gum (GG) modified screen printed electrode (La3+/ZnO/GG/SPE), and La3+/ZnO/GG/SPE was applied for the electrochemical detection of Ascorbic Acid (AA). The electrochemical methods, such as Cyclic Voltammetry (CV), chronoamperometry (CHA), and Differential Pulse Voltammetry (DPV) were used to evaluate the electrochemical performances toward ascorbic acid on the La3+/ZnO/GG/SPE. Good linear-ship was observed for ascorbic acid in the ranges of 1.0–700.0 μM, with the detection limits of 0.03 μM. Moreover, this sensor proved favorable to simultaneously determine ascorbic acid and acetaminophen. Finally, the modified electrode has fairly good performance during the employment of real sample analysis to determine the content of ascorbic acid. These results indicate that the La3+-doped ZnO nanoflowers are supposed to be a promising material in the electrochemical determination of ascorbic acid and acetaminophen in real samples.

Ag-doped TiO2/PVA nanofibers have many potential applications as a photoanode of dye-sensitized solar cells (DSSCs). In this study, we report the fabrication of DSSCs based on Ag-doped TiO2/PVA nanofibers as photoanode, graphene oxide as a Pt-free counter electrode catalyst, and natural dye sensitizer. Ag-doped TiO2/PVA nanofibers were fabricated using an electrospinning method. The electrospun nanofibers were characterized by a scanning electron microscope, X-ray diffraction, Fourier transform infrared spectroscopy and thermogravimetric analysis. The nanoparticle content of lower 100 mg/mL, and the electrospun nanofibers were uniform. Based on the results of the characterization analysis, the electrospun Ag-doped TiO2/PVA nanofibers were successfully prepared with diameters from 100 to 400 nm. They were used as photoanodes of DSSCs using a natural dye sensitizer extracted from the leaf of the magenta plant. The highest power conversion efficiency of DSSCs with Ag-doped TiO2/PVA nanofibers was 0.6% from the J-V curves. This approach would be a potential application for fabricating a solar cell based on composite fiber, Pt-free catalyst, and natural dye sensitizer.

In this research, MNPs were fabricated and coated by the co-precipitation method. The study of this process was performed in a two-level factorial design framework. The effect of a polymeric agent, the strength of the alkaline solution, and the temperature on the magnetic properties MNPs were studied in this design. the structure, morphology, size, appearance, and magnetic behavior of modified MNPs were investigated using XRD, FT-IR, TEM, and VSM. The results obtained from the spectra show the modified MNPs have superparamagnetic behavior with high saturation magnetization (𝑀𝑠) and small coercivity (𝐻𝑐). The mean size of coated MNPs was determined 10 nm, saturation magnetization 60.98 emu/g, and magnetic coercivity 8.26 G.

Dextrin nanoparticles are usually applied as biocompatible biopolymers. Natural catalysts such as nanodextrin have high catalytic activity. Dextrin has attracted researchers' attention because of its unique chemical structure, water-solubility, biodegradability, biocompatibility, abundance, affordability, and availability to produce the applied materials. On the other hand, dextrin is a suitable substrate for trifluoride ions and some metal ions due to its hydroxyl groups. Thus, the nano-Fe3O4@dextrin/BF3 catalyst was synthesized with readily available, unique, and efficient capability. The synthesized catalyst was characterized by different techniques such as Energy-Dispersive X-ray (EDX) analysis, Fourier Transforms Infrared (FT-IR) spectroscopy, X-Ray Diffraction (XRD) pattern, Scanning Electron Microscopy (SEM) image, and Thermo Gravimetric Analysis (TGA). Then the effect of adding nano-Fe3O4@dextrin/BF3 to the reaction of aldehydes, ethyl acetoacetate, and urea was studied on the synthesis of 3,4-dihydropyrimidin-2(1H)-ones derivatives under solvent-free conditions using an electrical mortar-heater. The synthesis of 3,4- dihydropyrimidin-2(1H)-one derivatives was carried out at 70 ˚C using a negligible amount (30 mg) of catalyst, in a short time of 20 min with a very suitable yield of 80-92%.

Recent advances in the development of magnetic nanoparticles modified with biodegradable polymers have shown promise in the improvement of therapeutic approaches for the clinical management of cancer patients. In this study, polycaprolactone -polyethylene glycol – polycaprolactone (PCL-PEG-PCL) copolymers modified with magnetic nanoparticles were used for encapsulation of doxorubicin (DOX) and chrysin (Chr) anticancer drugs by dual emulsion (W / O / W). The effect of temperature and pH on drug release was investigated. The release of the doxorubicin drug in pH 7.4 and 5.8 were 26.5% and 30.6%, respectively after 144 h. In chrysin drug, the release of drug in pH 7.4 and 5.8 was equal to 45% and 49%, respectively after 144 h. The kinetics of the drug's release was also studied based on zero-order, first-order, Higuchi, and Korsmeyer-Peppas models. From the kinetic models, based on the correlation coefficient, Higuchi (R2=0.9017) and Korsmeyer-Peppas (R2=0.9639) models were found to be the best models for doxorubicin and chrysin, respectively. After performing kinetic studies, the diffusion coefficient of drug release was also studied. The drug distribution was considered uniform, and the system was investigated in Cartesian and spherical coordinates. The results showed that the diffusion coefficient of drug release followed Fick's law. The diffusion coefficient decreased with increasing time due to decreasing the concentration difference.

Inhibition of glycogen synthase kinase-3 (GSK-3), β-secretase 1 (BACE-1) and acetylcholinesterase (AChE) could block one of the initial pathological events of Alzheimer's disease (AD). Recently, a new class of drugs has been developed with significant potential for GSK-3 inhibition. In this research, to the discovery of the new ligand as the potential multi-target drug with effective anti-Alzheimer's action a detailed computational investigation has been carried out on the effect of one of the most important drugs of such class on BACE-1 and AChE enzymes. The results of the binding free energies (ΔGBind) showed that the binding of this drug to AChE (-67.77 kJ/mol) is thermodynamically more favorable than BACE-1 (-22.35 kJ/mol). Examination of dynamic properties such as the root mean square fluctuation (RMSF) and the propensity for the secondary structure demonstrated that due to the decrease in the β-sheet and β-bridge content as well as the increase in the random coil content of BACE-1 in the presence of the drug, this enzyme was completely more flexible than AChE. The free-energy landscape (FEL) based on the first and second motion modes (PC1 and PC2) indicated that the large concerted motions of BACE-1 found in the simulations were particularly more sensitive to this drug than AChE.

Graphene Oxide has been synthesized using Hummer’s method by the oxidation of graphite powder using reagents like potassium permanganate, Sulphuric acid, hydrogen peroxide, and distilled water at low temperatures. The filtered suspension of graphene oxide was changed to a dry powder at room temperature. Synthesized Graphene oxide was further modified by functionalizing using diamine 2,6-bis(4-aminophenoxy)benzonitrile (BAAP) by ultrasonication and reflux methodology, air-cooled mixture was washed with the equimolar ratio of ethanol and water which was dried at room temperature and followed by drying in the oven at 80 oC. The sample was characterized by Fourier Transform InfraRed (FT-IR) spectroscopy which confirmed all required functional groups and proved the functionalization and modification of Graphene Oxide. Further, UV-Visible spectroscopy confirmed the slight reduction of graphene oxide by the redshift which is due to the chromophoric effect of diamine. X-ray diffraction also confirmed the expected d-spacing due to the covalent reduction of graphene oxide by shifting the peak position towards higher 2θ values. The cyclic voltammetry results are in a quasi-rectangular shape, due to the pseudocapacitance behaviour of diamine functionalized graphene oxide; successfully synthesised and functionalized graphene oxide showed electrochemical stability and an increase in capacitance with an increase in scan rates which is the promising property for supercapacitance to ensure energy storage and conservation.

Three amine-functionalized resins were prepared by suspension polymerization of vinyl-benzyl chloride, divinylbenzene, and subsequent amination process. The effect of chain length and cyclic amine on the performance of resins was investigated in a multicomponent system (Re & Mo). Different amines were used in the investigation. Different analyses such as Scanning Electron Microscopy (SEM), Fourier Transform InfraRed (FT-IR) spectroscopy, Inductively Coupled Plasma- Optical Emission Spectrometry (ICP-OES), Kiejdahl’s and Volhard’s methods were used to characterize the synthesized resins. The synthesized resins then were assayed in a batch mode using binary solutions of Re(VII) and Mo to evaluate their efficiency in the selective sorption of rhenium ions. Among all investigated resins, resin C revealed better separation properties in acidic solution (pH=1) with the highest sorption capacity up to 46.4 mg Re/g and a distribution coefficient of 870 that is more attributed to a steric barrier created against the polymeric molybdenum ions that are larger than objective ions in the studied system.

Heterogeneous CuO-ZnO/Al2O3 is widely used in various petrochemical plants to synthesize a low-temperature water gas shift reaction. Six different synthesis routes, co-precipitation, deposition-precipitation, ultrasonic deposition precipitation, incipient wetness impregnation, ureaco- precipitation gelation method, and combined incipient wetness impregnation-urea combustion, were compared for the synthesis of a catalyst with 20/5/75 weight ratios for CuO-ZnO/Al2O3. The products were analyzed and compared through XRD, SEM, BET analysis, and an activity test. The catalyst prepared by the incipient wetness impregnation-combustion urea method (IWI-Urea) showed the highest activity for CO conversion (47%) among the other synthesized products, with CO conversion ranging from 1.3 to 39%, and a commercial catalyst with 8.8% CO conversion. Additionally, the optimum operational condition for the activity test, including reaction temperature, space velocity, and steam-to-CO ratio, was studied on the catalyst with the highest activity (synthesized through the IWI-Urea method). Experimental results also indicated that at lower temperatures, a feed space velocity of 30000 h−1 or higher led to the greatest CO conversions. Steam to CO ratio of 4 was also found to be optimum over the range of experimental conditions employed in this study. Reaction temperature was found to have the most significant effect on CO conversion compared with other operation factors employed in this study.

Studies on the epoxidation of fatty acids have garnered much interest in recent years due to the rising demand for eco-friendly epoxides derived from vegetable oils. This study aims to optimize the process parameters of epoxidation of palm oleic acid via an in situ peracid mechanism with an applied homogenous catalyst. Oleic acid was epoxidized using performic acid-generated in situ through the reaction between hydrogen peroxide and formic acid when sulfuric acid was applied as a catalyst. The optimum reaction condition of epoxide was at the temperature of 45°C, the molar ratio of formic acid to oleic acid at 1.64:1 and the molar ratio of hydrogen peroxide to oleic acid at 2:1. Lastly, a mathematical model was developed using the numerical Runge Kutta-4th Order method. In the model, the method was applied with a genetic algorithm optimization to determine the process model that fit the experimental data using MATLAB software. After 100 iterations, the reaction rate constant for epoxidized oleic acid production was: k11 = 1.9305 L/mol. min, k12 =15.2284 L/mol. min, k21 = 0.0570 L/mol. min, k31 = 0.0106 L/mol. min. Overall, epoxidized oleic acid was successfully produced by in situ performic acid mechanism with 80% relative conversion to oxirane.

One of the main challenges in uranium extraction treatment is how to improve the adsorption performance of uranium with high adsorption capacity by using a simple and environmentally friendly technique. To tackle this challenge, in this study, effective eco-friendly adsorbents were synthesized based on chitosan-tannic acid (TACH) via a solution mixing technique. The chemical structures of the obtained adsorbents were characterized using Fourier transmutation InfraRed (FT-IR) spectroscopy, Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray (EDX) analysis. The effect of pH, temperature, adsorbent dosage, contact time, and initial U(VI) concentration on the removal capacity of the made adsorbents was investigated. The thermodynamic behavior and kinetic properties were studied. The adsorption data fit with the Lagergren equation, the sorption reaction is more favorably to be pseudo-second order sorption. The adsorption capacity of uranium achieved 155 mg/g which accords with Langmuir isotherm (150 mg/g). The synthesized TACH adsorbent showed the highest absorbance at PH 3, contact time 90 minutes, and temperature 25°C. These features make the prepared adsorbents in this study applicable as eco-friendly biopolymers with high uranium adsorption performance.

This work reported a new perspective on improving the green synthesis of titanium dioxide (TiO2) nanoparticles (NPs) from Aloe vera plant leaf extract and their incorporation into membranes for several applications. The X-ray diffraction of the powder depicted that the size of the samples TiO2 NPs (1 h) and TiO2 NPs (5 h) were 83 ± 15 (Ø2) nm and 23 ± 1.6 nm (Ø1), respectively. With two sizes of TiO2 NPs as an additive, cellulose acetate (CA) membranes and a series of TiO2/CA hybrid membranes were prepared using a phase-inversion method. The membrane characterization was carried out by Fourier transform-infrared spectroscopy, scanning electron microscope (SEM), water content, contact angle, porosity, and pure water flux measurements. The cross-section SEM images indicated that the size of macro-voids was reduced and the width of the membrane pores was slightly increased by the addition of TiO2 (Ø1). Membrane performance has been investigated in terms of dye Remazol Brilliant Red F3B (Reactive Red 180, RR 180) removal, which could be, however, affected by the competitive effect of another chemical species present in the solution such as NaCl salt. Indeed, NaCl decreased the retention rate of dye due to electrostatic interactions, as the chloride ions compete with the anionic dye molecules during the complexation process. The retention rate decreased at alkaline pH due to interaction forces between the membrane surface and anions of the RR 180.

The present work describes the adsorption of the anionic dye Congo Red (CR) by materials based on Activated Montmorillonite (AM), graphene oxide (GO), and gelatin (G). The materials were prepared and characterized by X-Ray Diffraction (XRD), infrared spectroscopy (FT-IR), and thermal analysis (ATG/DTG) in the previous study. Adsorption experiments of CR dye on GO/AM at different ratios of GO were performed to evaluate the adsorption efficiencies. The maximum adsorption capacity of anionic dye (CR) onto (GO / AM10%) composite was insufficient. To improve the adsorption capacity, a cationic-charged component such as gelatin was added to obtain a new composite (GO/AM/G). Therefore, the effects of several factors on the adsorption capacity of (GO/AM/G) composite, such as the pH of dye solution, adsorbent dosage, contact time, initial dye concentrations, temperature, and regeneration, were investigated. In addition, the kinetics of dye adsorption followed the pseudo-second-order model, and the adsorption isotherm was very well described by the Freundlich model. Afterward, the study of the temperature’s effect on the adsorption rate indicated that the reaction was exothermic with the medium disorder. The values of the free energy showed that the nature of the adsorption was physisorption. The reusability of the composites using 0.1N HCl for over six cycles indicated the economic significance of these materials as adsorbents. The fast removal rate in a wider range of pH and the easy reusability and regeneration make the composite (GO/AM/G) a prospective material for dye adsorption from aquatic environments.

The widespread use of aluminum-based food packaging materials has significantly contributed to an increase in aluminum waste generation, the majority of which ends up in landfills. To address this issue, the current study attempted to recycle Waste Aluminum Cans (WAC) by converting them into an effective electrode for the treatment of Acid Red 18 (AR18) dye via electrocoagulation (EC). Chemical pre-treatment was used for the de-coating of WAC before its application in the EC process. A parameter study was then carried out in a batch monopolar EC cell with two chemically pre-treated WAC electrodes connected to an external DC Power supply to study the effects of current density (10 - 30 mA/cm2), initial pH (3 - 11), and initial dye concentration (50 - 250 mg/L) up to 30 min of reaction time. The best-operating conditions were found to be at a current density of 25 mA/cm2, an initial pH of 6.8 (original pH of dye) and an initial dye concentration of 100 mg/L with a nearly completed decolorization of 99.4 %. The kinetic model of the various current densities was well-fitted by the first-order reaction, with R2 values ranging from 0.8955 to 0.9914. The mathematical model for the decolorization rate of AR18 dye was successfully developed based on the reaction kinetics and empirical models. The predicted data was in good agreement with the experimental data to validate the developed mathematical model. The characterization analysis of the flocs confirmed that the main dye removal mechanisms were through charge neutralization, coagulation, and adsorption of dye onto the Al(OH)3 flocs. In conclusion, the WAC was successfully utilized as an effective electrode for the decolorization of AR18 dye via the EC process.

Electrocoagulation (EC) is one of the most effective electrochemical wastewater treatment techniques for removing color and organic pollutants from wastewater, and reducing sludge formation. In this study, the removal of Remazol Ultra Red RGB (reactive red 239) dye, which is used for commercial purposes, by the EC process was investigated. For this purpose, an electrochemical reactor was designed using monopolar parallel connected aluminum and iron electrodes. The effect of operational parameters such as the initial pH of the solution, current density, and electrolysis time were investigated to achieve higher color, Chemical Oxygen Demand (COD), and turbidity removal efficiency. The optimum conditions of the EC process were determined by evaluating the data obtained as a result of the experimental studies. It was observed that the removal efficiency increased with the increase of the electrolysis time and stabilized after 20 min. The optimum experiment conditions for the aluminum electrode were pH:3, current density of 50 A/m2, and conductivity of 250 μS/cm, for the iron electrode was pH: 5, current density of 75 A/m2, and conductivity of 500 μS/cm was found as. In all studies, the mixing speed was chosen as 250 rpm. As a result of this study, 95.49-99.94% color, 89.34-66.83% COD, and 92.18%-83.15% turbidity removal efficiencies were obtained with aluminum and iron electrodes under optimal conditions. Under optimum conditions, electrical energy consumption was calculated as 11.48 for Al, 6.60 kWh/m3 for Fe, and the energy consumption 0.56, 0.46 kg/m3. As a result of the experimental studies, high removal efficiencies were obtained in color, COD and turbidity removal with the EC process. As a result, it was concluded that EC treatment is an effective method for the purification of synthetic textile dyestuffs.

In the present study, an organic wastewater industrial pollutant such as a phenol was removed by the improved modified adsorbents: NH3-activated carbon, and NaOH-activated. When the activated carbon ACDK was recovered from agricultural waste Date Kernel and prepared via pyrolysis and thermal activation at 850 ° C. The modification of the activated carbon surface ACDK was ready chemically with the impregnation in the 10wt % ammonia solution to obtain a modified adsorbent: NH3-ACDK, the impregnation of ACDK in 10 wt% Sodium Hydroxide solution for the second modified adsorbent: NaOH-ACDK. The modified functional samples were characterized by SEM, FTIR and DRX, TGA-DSC. The results established that phenol molecules were favorable for adsorption on the nitrogen group and hydroxide group of activated carbon at pH 4, solution temperature (28°C), and contact time (60-100 minutes). The adsorption kinetics of phenol on the modified adsorbents were better adapted to the pseudo-second-order adsorption model with (R² = 0.985) for NH3-ACDK, (R² = 0.980) for NaOH-ACDK. The adsorption isotherm follows the Langmuir design and is fitted well compared to Freundlich models with (R2= 0,999) for NaOH-ACDK, Langmuir, and Freundlich isotherms models fit the experimental equilibrium data for NH3-ACDK) with correlation coefficient (R²≥ 0,989). The removal percentage of phenol on NH3-ACDK, and NaOH-ACDK was 97,6 % and 70,3%, respectively.

This paper presents a new application of the Rotating Disc Contactor as an extractor of essential oil from a medicinal plant. Its capability for a solid-liquid extraction was tested. The extraction of essential oil from fennel seeds using a 70 % (v/v) ethanol-water solution was amLomplished in different particle sizes, rotor speeds, and solvent ratios per solid. The modeling of experimental data obtained from each sample's GC analysis was implemented through the response surface methodology of two mathematical regression models. Findings indicated that a linear model is applicable for estimating the extraction yield. Also, in the optimum condition (Least size of particle; Highest solvent per solid ratio, Highest rotor speed), the extraction yield of Anethole (the major component in fennel essential oil) was 1.387.

Turkey has the largest boron reserves in the world with a rate of approximately 72%. The most common commercial boron reserves in Turkey are colemanite, tincal, and ulexite. Boric acid, which is the most commonly used boron compound in Turkey, is obtained from the dissolution of colemanite with sulfuric acid. In the present study, an aqueous medium saturated with sulfur dioxide instead of sulfuric acid was used in order to obtain boric acid. Colemanite ore was flash calcined at various temperatures and optimum dissolution conditions of the ore obtained in water saturated with SO2 were examined via the “Taguchi Method”. In the trials, flash calcination temperature (500, 600, 700, 800 °C), reaction temperature (50, 60, 70, 80 °C), solid-liquid ratio (0.15, 0.20, 0.25 and 0.30 g/mL), grain size (-500+355, -355+212, -212+150, and -150 μm), and reaction time (15, 30, 45, and 60 minutes) were selected as the parameters and velocity of gas flow and mixing speed were considered as constant in all the experiments. In addition, experiments were carried out at atmospheric pressure. Accordingly, optimum conditions were found as flash calcination temperature of 500oC, reaction temperature of 50oC, grain size of -212+150 μm, solid-liquid ratio of 0.30 g/m, and reaction time of 60 minutes. The estimated dissolution under these conditions was 99.47% and dissolution of 100% was obtained in the experiments conducted. The aim of the study was to obtain more economical and high-purity boric acid compared to sulfuric acid via an environmentally friendly process without any waste.

To investigate the impact of the different geometry and physical conditions parameters on the industrial process of amino acids recovery from sugar beet thin juice (TJ), several techniques such as computational fluid dynamics and scale-down approaches have been applied. Process modeling can support the design and optimization of all these processes. The Model, considering the process operative parameters and process stoichiometry, using the data from the Egypt Beet Sugar Industry, give an estimation of the process efficiency, product quality, selectivity as well and the condition for an optimal yield. Combining the results obtained by the model with the data obtained by the scale-down devices, the optimal process configuration and all requirements of the fluid sugar were simultaneously identified in an early phase of development for the subsequent processes of sugar manufacturing. In this case, the choice of an ion exchanger is associated with the development of a method for extracting an amino acid based on the study of the dynamic patterns of sorption and desorption, depending on several factors. These include the shape of the ion exchanger, the degree of its granulation and cross-linking; parameters of ion-exchange columns; flow rate and temperature of working solutions; and efficiency of the eluent. Furthermore, to maximize the utilization of the amino acids extract was added to the Sugar Beet Pulp (SBP) to produce High Amino acid Beet Pulp (HABP) with a high nutritional value and subsequently high marketing value. The results of this paper provide useful information for the design and modeling of beet juice-based production of amino acids integrated with beet processing for sugar production.

This paper mainly studies the design of a concentration gradient generator. Since the fractal principle has been shown to have unique geometric properties, we study the fractal principle together with the concentration gradient generator. We designed an obstacle based on the Cantor structure fractal applied the obstacle to the concentration gradient generator and then used the simulation software COMSOL Multiphysics 5.2a based on the finite element theory to carry out the numerical simulation. (a) The effect of fractal obstacle series on the concentration gradient, (b) the effect of microchannel height on the concentration gradient, and (c) the effect of different inlet velocities on the concentration gradient. A series of conclusions are obtained. The primary and secondary fractal obstacle has little influence on the concentration gradient. With the increase in the height of the microchannel, the change in the concentration gradient is small. The concentration gradient curve at different flow rates of the three-inlet concentration gradient generator shows a normal distribution trend. When the velocity decreases from 5×10-3 m/s to 1×10-5 m/s, the peak value of the curve decreases from 0.6 mol/L to about 0.35 mol/L. The concentration gradient curves at different flow rates of the two-inlet concentration gradient generator show a linear trend. When the velocity decreases from large 5×10-3 m/s to 1×10-5 m/s, the vertex value of the curve decreases from 1 to about 0.5 mol/L of complete mixing.

Nanofluids play an important role in order to augment of the heat transfer characteristics in many energy systems. As compared to usual fluids, nanofluids comprise better physical strength and thermal conductivity. Our aim in studying this work is to numerically interpret the flow and heat transfer features of copper oxide (CuO) nanoparticles in the coexistence of thermal radiation and inclined magnetic fields. The model equations are first simplified by the similarity transformations and then finite difference discretization is used to apply the numerical technique known as the successive over-relaxation method. We have mainly examined that how much the thermal radiation and inclined magnetic field affect the nanofluid flow. The impacts of involved parameters are overlooked with the help of tabular and graphical representations. The consequences evidently point out that the effect of inclination is to devaluate the heat transfer and elevate the skin friction on the surface. The thermal radiation phenomenon is responsible for an increase in the temperature.

The surface tension of aqueous polymer solutions is an important property that plays a vital role in mass and heat transfer. In this study, the surface tension of a polymer mixture is modeled using four algorithms (Adaptive Neuro-Fuzzy Inference System (ANFIS), Multi-Layer Perceptron (MLP), Radial Basis Function (RBF), and Adaptive group of Ink Drop Spread (AGIDS) ) which has been developed in the soft-computing domain. In this paper, four models for predicting the surface tension are applied and the results were compared with our published experimental data and it was found that the predictions of these models fit the experimental data very accurately. Also, a comparison has been done to evaluate the effectiveness of the relevant four algorithms in the current problem. The simulation results have shown that ANFIS and RBF model predictions are more accurate than the two others in the current problem.

Current wind systems are intermittent and cannot be used as the baseload energy source. The research on the concept of wind power using direct thermal energy conversion and thermal energy storage, called Wind-powered Thermal Energy System (WTES), opened the door to a new energy system called Wind-thermal, a strategy for developing baseload wind power systems. The thermal energy is generated from the rotating energy directly at the top of the tower by the heat generator, which is a simple and light electric brake. The rest of the system is the same as the towertype Concentrated Solar Power (CSP). This paper’s results suggest that the energy and exergy performance of the WTES (62.5% and 29.8%) is comparable to that of conventional wind power, which must be supported by the backup thermal plants and grid enhancement. This cogeneration nature of the WTES system makes this system suitable for using wind power as a direct heat source in several heat-demanding processes such as chemical production. Also, the light heat generator reduces some issues of wind power, such as noise and vibration, two main bottlenecks of wind power technology.

The focus of this full-scale study is to investigate the operation of the Bosrucktunnel ventilation during the fire. In this regard, the performance of the ventilation system and all related sub-systems were evaluated in a standard Commissioning test. For this purpose, a fire test with a heat release rate of 3-5 MW was considered according to RVS standards. The mentioned capacity of the fire is equivalent to a common passenger car fire. This fire capacity can’t represent a clear perspective from the ventilation operation during higher or extended fires. However, the system reaction and ventilation strategy are almost the same regardless of the size of the fire, particularly at the beginning of the fire. Furthermore, a general evaluation of control systems and the investigation of the entire process from incident detection to system response was necessary for this experimental and numerical study. Therefore, a CFD model was developed using a Fire Dynamics Simulator (FDS), an open-source software, for numerical simulation. Due to the relatively long length of the tunnel (5.5 km) and various safety equipment, simulating the fire and the system response was a big challenge. In such cases, simulation of the ventilation using the entire structure of the tunnel in the computational field is not easily possible, and it is not necessary. For this reason, a simplified calculation domain with a suitable boundary definition is assumed for simulation. The other required boundaries were defined using tunnel data, ambient, and tunnel conditions during the fire test. The performance of the ventilation was confirmed in smoke management in the specified schedule in the fire test. A numerical simulation was carried out to investigate the behavior of hot smoke, air velocity, and temperature distribution around the fire location. In addition, more useful information was obtained from numerical simulation, including the timing of related systems response in facing a fire, which is very important in emergencies. This information can help to deal with high-capacity fires.

Esterase is a biotechnologically important enzyme as it hydrolyzes water-soluble short-chain fatty acid esters. We tried to isolate and purify the esterase enzyme from Aspergillus versicolor in this investigation. The enzyme was purified with ammonium sulfate precipitation, dialysis, and column chromatography. The enzyme was salted out, with maximum specific activity at 60 to 70 percent of saturation during precipitation. The column chromatography was performed with Sephadex G-75 to purify the esterase from Aspergillus versicolor and was able to achieve the purification fold of 6.9 nM. The partially purified enzyme was analyzed in SDS-PAGE and showed a single 32-kDa band. The partially purified esterase enzyme was checked for its optimum conditions for maximal enzyme activity. This enzyme has a huge industrial potential which makes a significant contribution to eco-friendly approaches such as textile, food, and agrochemical industries as well as for bioremediation.

Three freshwater microalgae; Scinaria turgid member in Radophyta; Cystoseira myrica of Phaeophyta, and Chlorodesmus casonus of Chlorophyta, were tested for tolerance and biosorption of actinides elements from the phosphates of El- Sibaiya west and east. The obtained results revealed that the metal biosorption process by Cystoseira myrica gives a great variety for the complete biosorption of uranium in the phosphate west sample 100 % and 71.6 % in the east sample, Chlorodesmus casinos give the same biosorption 63% in the east and west phosphate sample while Scinaria turgid give almost the same biosorption (56.8% - 60%) in the west and east phosphate. On the other side thorium was completely absorbed by the three types of algae, The Adsorption process could be efficient and economically cheap by Cystoseira myrica for the removal of U and Th from El-Sibaiya phosphates to be used in agriculture as compost.

Bacterial NanoCellulose (BNC), a unique and promising natural polymer, due to its renewability, excellent biological features, remarkable physical properties, and special surface chemistry has received much attention for biomedical applications in recent years. There are several methods for synthesizing BNC, each with its own set of benefits and drawbacks. Modification approaches are used significantly to improve the properties of BNC or BNC-based structures for long-term and short-term biomedical applications. The fabrication of BNC-based antimicrobial materials for wound dressings, drug delivery, and hard and soft tissue regeneration is a major concern of many researchers. A wide range of biomaterials such as antibiotics, metal, and metal oxide nanoparticles are used for preparing BNC-based antimicrobial structures. In this review, we presented the main and necessary information on the key aspects of synthesis and BNC properties. Furthermore, recent literature related to the preparation and biomedical applications of BNC-based materials is reviewed. Aligned with the current trends in BNC, BNC-based biocomposites present a great field to be explored and other amazing characteristics can be expected in relation to soft and hard tissue repair, drug delivery, and other biomedical applications in the near future.