Journal of Applied Research in Chemistry
Year:2020 | Volume:13 | Issue:4 |Papers Count:12

In this study, a polymer film of poly-(vinyl alcohol) made by solvent/casting method was used to prepare the drug release system for fluconazole. The cross-linking of polymer films was done by thermal method. The formation of a possible reaction between the polymer and the drug was observed by FT-IR and there was no chemical reaction between polyvinyl alcohol and fluconazole. The rate of drug release in PBS was investigated by spectrophotometric method. The results showed that the drug release rate in the cross-linked film was lower than the non-crosslinked sample, so that in the cross-linked sample, about 95% of the drug was released within 60 min, while the release rate of non-cross-linked sample was reduced to 30 min. Furthermore, the XRD test indicated that the fluconazole was loaded amorphous in PVA film. The mechanism and kinetics of the release of the samples were evaluated and it was found that the mechanism of fluconazole release from the polyvinyl alcohol films in all cases was Fickian and its release rate followed the first-order model. The polymer film can be used locally for loading and releasing fluconazole and decreases the side effects of oral usage of the drug.

In this article, the mercury-impregnated γ-alumina nanoparticles were prepared using impregnation of γ-alumina nanoparticles with mercury acetate into the solution of water/ isopropanol, followed by hydrolysis, washing, filtration, and drying at the room temperature. The structure of these nanoparticles were studied using X-ray diffraction (XRD) pattern. The XRD pattern was used to confirm the binding between mercury impregnated nanoparticles and thymine organic base in the DNA of target cell. The biological effects and toxicity of γ-alumina and mercury impregnated γ-alumina nanoparticles on the cancer cells (Hella) and bone marrow stem cells were examined using the MTT test. Based on the results, the toxicity of the mercury impregnated γ-alumina nanoparticles on Hella cancer cells was found to be higher than that of stem cells. In other words, the mercury impregnated γ-alumina nanoparticles had a significant effect on removing the Hella cancer cells. It was also found that in the lower concentrations, pure γ-alumina nanoparticles had lower toxicity than mercury impregnated alumina.

The method is based on the adsorption of silver on sodium dodecyl sulfate (SDS)-coated nano-alumina, which is also chelated with 4-dimethylaminobenzylidene rhodanine. The results displayed that adsorbent had the highest adsorption capacity for Ag in ions mixture system. Optimal experimental conditions including pH, adsorbent dosage, and contact time have been established. Langmuir and Freundlich isotherm models were applied to analyze the experimental data. The effect of foreign ions were studied. In batch system relative standard deviation (R. S. D, n=9) under optimum condition was obtained 1. 54 % and detection limits 7. 7 μ g. L-1 (3Sb/m) were obtained. Different parameters such as, sorbent amount, eluent type, eluent volume, sample flow rate, and sample volume were determined for the preconcentration of metal ions with the sorbent in column system. Relative standard deviation (R. S. D, n=8) under optimum condition is obtained 2. 35 % and detection limits 8. 9 μ g. L-1 (3Sb/m) are obtained. This method is simple and sensitive for measurements of silver in water, soil, and real samples in batch and column systems.

Recently, a new group of compounds, namely switchable hydrophilicity solvents, has been introduced into the extraction field. In this study, a pH assisted homogeneous liquid-liquid microextraction method based on switchable hydrophilicity solvents followed by GC-MS detection has been developed for preconcentration and determination of polycyclic aromatic hydrocarbons (PAHs) in water samples. The extraction method includes two steps. In the first step, the waterimmiscible solvent (N, N-Dipropylamine) is dissolved in the aqueous phase using hydrochloric acid as a reagent. Afterwards, the separation of organic and aqueous phases is accomplished by the addition of sodium hydroxide. The effects of experimental parameters of the extraction such as temperature, time, the volume of acceptor phase, pH of donor phase, and ionic strength of solution were investigated. Under the optimum conditions, the proposed method provided good linearity in the range of 2– 1000 μ g L− 1 for anthracene and pyrene and 4-1000 μ g L− 1 for naphthalene. Also, limit of detection for anthracene and pyrene was 0. 6 μ g L− 1 and for naphthalene was 1. 21 μ g L− 1. Extraction repeatabilities were obtained as RSD% in the range of 4. 3-6. 8. Finally, the application of the proposed method for the analysis of target analytes in different water samples was successfully investigated.

From the reaction of melamine with sulfuric acid and nitric acid, two solid acids Melamine-(H2SO4)3 and Melamine-(HNO3)3 are produced. The mixture of Melamine-(H2SO4)3 and Melamine-(HNO3)3 acts as a powerful system as an alternative of hazardous H2SO4/HNO3 system for the oxidation of 1, 4-dihydropyridines under heterogeneous, solvent/metal-free, and mild conditions. In the proposed mechanism, the NO2 + was generated from the mixture of two solid acids and this cation performs the oxidation reaction. This procedure offers advantages such as short reaction times, simple work-up, excellent yields of products without using transition metals and organic solvents. Reagents are cheap, safe, easy-handling, and the synthesis process of them is very simple.

The treatment of groundwater in order to remove the pharmaceutical contaminants from hospital wastewater and household sewage has always been a crucial issue as the most pharmaceutical pollution of groundwater is derived from hospital wastewater. In recent years important steps have been taken for removing the pharmaceutical compounds from water bodies. This research was an experimental study on a laboratory scale with the aim of comparing the efficiency of modified nanoclays (titanium dioxide/montmorillonitenanocamposite) and multiwall carbon nanotubes (MWCNTs) on removing ibuprofen in the presence of UV light. The results showed low efficiencies in ibuprofen removal using the modified nonoclays whereas the 98. 95% efficiency was obtained using MWCNTs and the optimized experimental parameters were 0. 06 g/l, 25 ° C, 15 mg/l, 7, and 2 hours as adsorbent amount, temperature, ibuprofen amount, pH, and the contact time, respectively. Equilibrium adsorption data fit to isotherm models and attained a better correlation with the order of models as Temkin (R2 = 0. 9737) > Langmuir (R2 = 0. 9554) > Freundlich (R2 = 0. 9503). The results of this research can be used in removing ibuprofen from hospital waste waters.

Volatile organic compounds (VOCs) contain a large and diverse group of chemicals that are very harmful for humans and the environment. Therefore, there is urgent need for removing these compounds. The goal of the present study is degradation of the ethyl acetate by photocatalytic process under UV and visible light irradiation. First, a series of lanthanide perovskite-type oxides (LaNiO3, LaMnO3 and LaCoO3) synthesized by sol– gel method and their physicochemical properties analyzed by XRD, SEM, TEM, and UV– Vis (DRS mode) spectroscopy. The XRD patterns confirmed the formation of perovskite-type oxides and the micrographs of SEM indicated that perovskite particles were nanosize with smaller size than 50 nm. The UV-visible absorption spectra of nanoperovskites also exhibited strong absorption at visible light region. The photocatalytic activity of nanoperovskites evaluated for the degradation of ethyl acetate and results showed that all nanoperovskites had a high performance in the removal of ethyl acetate and the LaNiO3 showed the highest activity. In the next step, the effect of operating parameters such as concentration of pollutant, photocatalyst form, type of light source, and air humidity on the efficiency of ethyl acetate removal investigated.

In this work, the effects of blending with polyolefins (PE and EPDM) on the melt behavior of PP were studied. Terblends having various compositions were produced and the melt behavior under stress was investigated using the rheological and sagging tests. In the stress sweep test, PP showed the poorer properties, the higher damping factor, and the lower modulus. By adding PE and EPDM, damping factor decreased, the modulus increased, and the elasticity improved. Rheological parameters of creep recovery test included zero shear rate viscosity, creep slope, and recovered strain. With increasing the PE and EPDM content, zero shear rate viscosity increased and creep slope decreased, meaning more strength of melt. Recovered strain increased as the PE and EPDM levels increased, hence the elasticity. An interesting synergistic effect was also observed. Each component was more effective at higher levels of another. The sagging rate of pure PP was very intensive, in comparison with the blends. At 10% of PE, at every level of EPDM, rate and amount of sagging decreased. Results proved that the blending with PE and EPDM improved the rheological behavior, melt strength, and the elasticity of PP.

In recent years, the discovery of an alternative fuel due to the limited availability of fossil fuels, rising of crude oil prices, and the importance of greenhouse gas emissions has been highlighted. So, demands to discovery and utilizing green fuels have been continually increased. Biodiesel is one of the most important members of this family of fuels. In this research, we have tried to study and evaluate the process of esterification of biodiesel production using ZIF-8 nano-structure synthesized by green, industrial and environmentally friendly method for the first time. The Zeolitic Imidazolate Framework-8 (ZIF-8) was selected of a subset of the large family of Metal-Organic Frameworks (MOFs), due to its high thermal and chemical stability and high contact surface as heterogeneous catalyst in the production process of biodiesel. Operating conditions including time, reaction, temperature, and molar ratio of alcohol to fatty acid related to the production of biodiesel were optimized by the response surface methodology using Design Expert software. The maximum yield of biodiesel production of 57. 62% has been achieved under reaction temperature 70 ° C, reaction time 70 min, 0. 05 g of ZIF-8 nano catalyst and minimum possible molar ratio of alcohol to fatty acid 14/65: 1. Furthermore, the amount of activation energy in the presence of the ZIF-8 was calculated 6. 375 kJ/mol.

Drag reduction prediction plays an important role in oil and gas industries. Due to the nonlinearity and instability of drag reduction, the precision of the commonly used conventional methods, including regression analyses, has been limited. A prediction model based on support vector regression (SVR) is presented in this paper to predict drag reduction by nanofluids in single-phase flow of water through horizontal pipes. To construct an effective SVR model, the SVR parameters must be set carefully. This study proposes a hybrid approach, known as support vector regression-genetic algorithm (SVR-GA), which searches for the optimal SVR parameters using GA, and accepts the optimal parameters to create the SVR models. The results indicated that the obtained drag reduction values by the proposed model are in good agreement with the experimental data. The performance of the SVR-GA model was compared with multiple linear regression (MLR). The coefficient of determination (R2) of 0. 9485 and 0. 8740; mean square error (MSE) of 0. 01177 and 0. 01772, for experimental and predicted data by SVR-GA and MLR models were obtained, respectively. This result shows that SVR-GA can be applied as an effective approach to predict drag reduction.

In this study, Ni/HZSM-5 nano-structure catalysts were synthesized through reverse microemulsion method. The main advantages of this synthesis method compared to other typical methods are better control on particle size distribution, favorable dispersion, surface area, and reducibility. The experiments of Fischer-Tropsch synthesis in the presence of Ni/HZSM-5 catalyst were conducted under operating conditions (i. e., temperature 493-513 K, pressure 15-25 bar, and gas hourly space velocity 900-2300 1/h). The purpose of training the adaptive neuro-fuzzy network is to find the size of the weights and biases in such a way as to minimize the error of the training data. To optimize the neuro-fuzzy model, Genetic Algorithm and Particle Swarm optimization were used to predict the product distribution of Fischer-Tropsch synthesis products using ANFIS, GA-ANFIS and PSO-ANFIS networks. For modeling, 17 experimental data were used, of which 80% were for training and the rest for model validation. All presented models have a correlation coefficient (R2) higher than 0. 97 which indicates the accuracy of modeling. Regarding the correlation coefficient and ARE, AARE and SD errors are the best networks for modeling the desired process of PSO-ANFIS.

Zeolites are crystalline and hydrated aluminosilicates from earth alkali and alkaline metals, which are used for the removal and separation of Pharmaceutical, colored, and metallic pollutants due to their chemical structure and proper surface area. In the present study, first, natural zeolite was powdered by ball mill, and after that, it was modified by a cationic surfactant of the cetyltrimethylammonium bromide. The modified zeolite was investigated by XRF, FTIR, SEM, BET, and XRD techniques, which is based on the BET test, The specific surface area, mean pore diameter, and total volume cavities of zeolite were 11. 931 m2/g, 31. 546 nm, and 0. 0941 cm3/g, respectively. Additionally, the efficiency of the sample was studied for removal of Amoxicillin from the aqueous medium. The results showed that environmental factors such as Adsorbent dose, contact time, pH, Temperature, and Amoxicillin concentration were effective in removal percentage. In addition, the experimental data of the amoxicillin-adsorption process better matched with the isothermal model of Ferndlich as well as kinetic of the pseudo-second order. According to the Freundlich model, adsorption capacity of amoxicillin with the adsorbent dosage 2 g/l, contact time of 180 min, pH=9, and initial concentration of 120 ppm was 37. 3 mg/g.