Journal of Applied Research in Chemistry
Year:2018 | Volume:12 | Issue:1 |Papers Count:13

In this work, a coordination polymer in bulk and nano-scale: [Zn (3-bpdh) Cl2] n(1), with 3-bpdh=2, 5-bis (3-pyridyl)-3, 4-diaza-2, 4 hexadiene ligand, has been synthesized and characterized by IR and NMR spectroscopies. The nanostructures of coordination polymer (1) were prepared by using ultrasonic waves and sonochemistry method, and the size and morphology of the particles were characterized by Scanning Electron Microscopy (SEM). The nanostructures were used as precursors to prepare zinc (II) oxide nanorods by thermolysis. The ZnO nanorods were identified and their diameters were estimated by XRD and SEM, respectively. Also, the ligand, bulk and nanoscales of coordination polymer (1) and zinc (І І ) oxide nanorods have been screened for antibacterial activities against Bacillus alvei bacteria caused by honey bee European foulbrood disease. The Minimum Inhibitory Concentrations (MIC) has shown moderate antibacterial activities in comparison to some standard drugs.

Technologies such as thermal and catalytic oxidation or biological treatment are usedto remove or reduce volatile organic compounds (VOCs) which are a major part of air pollutants. Nowadays use of nanocatalysts to remove environmental pollutants are highly regarded. In thiswork, the composite of Al2O3/CeO2/Clinoptilolite was synthesized, and then palladium activephase has been loaded on it by ultrasonic irradiation. Ultrasonic irradiation causes the profitdescription of active metal and improves structural properties of nanocatalysts. The purpose ofusing this catalyst is to take advantage of high specific surface area of alumina, acidic characteristicof clinoptilolite, and unique properties of CeO2 at the same time. Existence of CeO2 in catalystcauses increasing storage of oxygen, improving thermal and structural stability of composite andappropriate distribution of palladium metal on it. Characteristics of nanocatalysts are determinedby XRD, FESEM, BET, FTIR, and EDX analyses. Gas chromatography and catalytic oxidationpilot are used for evaluation of catalytic performance toward toluene abatement from pollutedair. XRD analysis results showed that the nanocatalysts have nanometer dimension crystals. BETanalysis showed that the synthesized nanocatalysts have high specific surface areas. The reactortest results confirmed that the composite nanocatalysts have activity and absorption ability ontoluene abatement.

In this study, two sulfonamide – Schiff base compounds "N'-(2-hydroxy-3-methoxybenzylidene)-4-methylbenzenesulfonohydrazide and 1, 2-bis(2-hydrxy-3-methoxy-benzylidenehydrazine) (1) and N'-(2-hydroxy-3-methoxybenzylidene)-4-nitrobenzenesulfonohydrazide and 1, 2-bis(2-hydrxy-3-methoxy-benzylidenehydrazine)(2)" were synthesized by sulfonyl chloride and Schiff base compounds. Copper and zinc oxides were coated bysynthesized compounds and were tested for antibacterial activity. All compounds were identified by NMR and FTIRspectra, X-ray diffraction (XRD), and elemental analysis. Scanning Electron Microscope SEM was used for themorphology of micro metal oxides before and after coating with Sulfonamide-Schiff bases compounds. Accordingly, antibacterial activity of compounds against Gram-positive bacteria (Staphylococcus epidermidis and Staphylococcussaprophyticus) and Gram-negative bacteria (Proteus mirabilis) were tested. It should be noted that both have highantimicrobial activities. The result of the study shows that the antibacterial activities of the synthesized sulfonamideschiffbases against gram positive and gram negative bacteria decrease after coating on micro metal oxides. It is alsoworth mentioning that Ampicilin and Penicilin have been utilized as two standard medicines for investigating theantibacterial activities.

Silica is the most used support for high-performance liquid chromatography columns. Mesoporous silica has attracted much attention due to its properties. Columns with spherical shapedmesoporous silica particles are superior for chromatographic applications because they providehigher efficiency and lower back-pressure compared to irregular particles. In this work, mesoporoussilica microspheres were prepared via a two-step synthesis process by using tetraethyl orthosilicate, amphiphilic triblock copolymer, cetyltrimethylammonium bromide, and ethanol. To obtain mesoporoussilica spheres with mean particle size about 5. 5 μ m (obtained by scanning electron microscopy), specific surface area about 670 m2/g and pore diameter about 7 nm (obtained by N2 adsorptiondesorption), parameters of synthesis were optimized. After surface functionalization with C18 (about21% C, obtained by elemental analysis), they were slurry packed into a column (25 cm × 4. 0 mm i. d. )and used for separation of alkylbenzenes containing 1-5 carbons, polycyclic aromatic hydrocarbons, and pyridine derivatives mixtures. Phenol and pyridine mixture were used for investigation of activesilanols. The synthesized C18-modified mesoporous silica microspheres showed good, repeatable andstable results for separation of above compounds. Among them, the highest efficiency of the column isfor benzene with 1484 theoretical plates. Resolutions of copmounds are between 1 and 4. According totailing factors, peaks are almost symmetric, except pyridine derivatives that show a little tailing.

The use of membrane has very specific role in the separation processes such as gasseparation and dehydration of the azeotropic feed. The most important step in any membraneprocess is selection of the membrane material and its fabrication. The ceramic membrane has beenmore attracted due to sufficient strength, thermal, and chemical stabilities. The ceramic membraneis a composite membrane containing three layers. The first layer is a macroporous support, thesecond layer is a mesoporous support, and the third layer is silica with micropores which playsa key role in the separation process. Therefore, the quality and uniformity of the third layer is soimportant that increases directly the efficiency of the separation process. In this article, a methodhas been presented in which the defects of silica are reduced. In this method, known as hotcoating, the support was heated before all usual coating. Reduction in gaps or defects and increasein continuity or uniformity of the silica layer was observed from SEM analysis. On the other hand, comparing the results of gas permeability test through hot coating and usual coting revealed thatthe exit gas flow rate was reduced significantly in hot coating. According to reduction in thicknessof the silica layer, the decrease in exit gas flux is attributed to increase in continuity and reduce indefects of the layer. So, the continuous or uniform silica layer is obtainable via hot coating throughfewer coating steps than usual coating.

In this work, the inhibitive behavior of metoclopramide tablet on the corrosion ofmild steel in 0. 5 M phosphoric acid solution was investigated employing potentiodynamicpolarization, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy(SEM) techniques. The results showed that the inhibition efficiency increased with increase in theconcentration of inhibitor, up to 300 ppm and the increase in temperature caused the reduction in theinhibition efficiency. Potentiodynamic polarization measurements indicated that the inhibitor actsas an anodic type inhibitor. The EIS measurements showed that by addition of the inhibitor up to300 ppm, the charge transfer resistance increased and the double layer capacitance (Cdl) decreased. The results obtained from potentiodynamic polarization and EIS were in good agreement. Theadsorption studies revealed that the adsorption of the inhibitor in the solution on the alloy surfacefollows Langmuir adsorption isotherm. The adsorption process is a spontaneous and exothermicprocess accompanied with the reduction of entropy. SEM investigations proved the formationof protective layers on the alloy surface after immersion in the solution and these observationsvalidate the adsorption performance of the inhibitor.

In this study, the performance of anti-wear in engine oil which contain nanomaterialadditive has been compared and evaluated to conventional engine oil, by using laboratory tests. Forthis purpose, magnetic iron oxide nanoparticles (Fe3O4) as a nanomaterial additive were selectedto use in Iranol Racing engine oil, SAE 10W40. At first the stability of the nano-fluid, obtainedby the nanoparticles, was confirmed by using UV and zeta potential devices. The iron oxidenanoparticles were characterized by scanning tunneling microscopy (STM), energy dispersiveX-ray spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR). The nanoparticleshave a diameter in the range of 8-13 nm. Size distribution of nanoparticles by dynamic lightscattering (DLS) was also investigated. Anti-wear performance of Fe3O4 nanoparticles in multigradeengine oil was evaluated by means of the four ball and falex test. The results generallyindicate the improvement of anti-wear performance engine oil which was prepared by addingnanoparticles. Magnetic iron oxide nanoparticles with concentration of 0. 1 percent, increase weldstrength from76. 32 to 92. 74 kgf and load wear index (LWI) from 250 to 315 kgf, in the four balltest. Additionally it has increased the falex test results (linear load carrying) from 1160 to 1220 lbf, compared to conventional engine oil.

In these research, the green synthesis of Ag nanoparticles (AgNPs) and AgNPs/Peachkernel shell (Ag/ P. K. Shell), using peach kernel shell as an environmentally benign support andSalvia hydrangea extract as the reducing agent in the absence of any stabilizer or surfactant isreported. Samples were characterized by Fourier Transform Infrared spectroscopy (FTIR), UVVisspectroscopy, Field Emission Scanning Electron Microscopy (FE-SEM) equipped with anenergy dispersive spectroscopy (EDS), Elemental mapping, X-ray Diffraction analysis (XRD), and Transmittance Electron Microscopy (TEM). These synthesized catalysts were used in thereduction of Methylene Blue (MB) and Rhodamine B (RhB) at room temperature. The Ag/ P. K. shell showed excellent catalytic activity in the reduction of these organic dyes. In addition, itwas found that AgNPs/Apricot kernel shell can be recovered and reused several times withoutsignificant loss of catalytic activity.

In this research, silver nanoparticles were deposited on nylon 6, 6 fibers with differentmethods including chemical, ultrasonic, and using colloidal silver solution. Also, the non-fibernanocomposite of nylon 6, 6-silver was prepared by dissolution of nylon 6, 6 in formic acid inthe presence of silver nanoparticles and extracted by acetone antisolvent. The morphologicalproperties, antibacterial properties, elemental analysis, and wash durability of prepared sampleswere examined. SEM images and EDS analysis confirmed the presence of silver nanoparticleson nylon 6, 6 in prepared samples before and after washing. The antibacterial capability of thesamples were determined before and after washing against gram positive bacteria (S. aureus) andgram negative bacteria (E. coli) using resazurin color change. The obtained results confirmed, thesample prepared by ultrasonic method has the most effective antibacterial property before andafter washing. According to the results of morphological observation and elemental analysis, it isdue to the high amount and uniform deposition of silver on the fiber surface. Also, according to theresults, non-fiber nylon6, 6-silver nanocomposite has the weakest antibacterial property and othersamples have intermediate properties

Fentanyl is a rapid-acting, analgesic drug, and a powerful opioid which is extensivelyused for anesthesia and chronic pain management. In this study, an electrochemical sensor basedon a nanocomposite of multi wall carbon nanotubes (MWCNTs) and iron (III) oxide (Fe2O3)nanoparticles on the surface of glassy carbon electrode (GCE) was investigated for the analysisof fentanyl drug in aqueous media. The surface of modified electrode was studied with scanningelectron microscope (SEM). The electrochemical behavior of modified electrode and determinationof fentanyl were performed by cyclic voltammetry and differential pulse voltammetry (DPV), respectively. The differential pulse voltammetry (DPV) measurement at the surface of modifiedelectrode presented the linear relation between the anodic peak current and fentanyl concentrationin tow range of 0. 08 to 1 and 1 to 100 μ M with limits of detection (LOD) of 0. 045 μ M. The effectof some potential interferences of electrode response was investigated. The proposed sensor wassuccessfully employed for the determination of fentanyl in human blood serum and urine samples.

Transdermal drug delivery systems with controlled release are a useful devicefor local transfer of pharmaceutical components to the damaged site and healthy layersof the skin. These devices are particularly suitable for wound healing in cases wherelong-term treatment and frequent wound dressing exchange are needed. In this research, due to the superior feature of nanofibers, high surface to volume ratio, electrospinningtechnique was used to make dressings, for antimicrobial photodynamic therapy (aPDT), using biocompatible and biodegradable polymers such as poly (Ɛ-caprolactone) (PCL). Optimized conditions (voltage, flow rate nozzle to collector distance rotation) for obtainingnanofibers PCL/Extract (10, 30, 50%V/V) are as follows: Voltage of 12kV for nanofibersPCL and PCL-E50, and 20kV for PCL-E10 and PCL-E30, flow rate of 0. 1ml/h for PCLand PCL-E50, and 0. 5 ml/h for PCL-E10 and PCL-E30, and distance of 100 mm for allthe nanofibers.

1, 4-Dihydropyridines and 2, 3-dihydroquinazolines are heterocyclic compounds thathave pharmacological and biological properties and most of their derivatives are produced inpharmaceutical industries. In this study preparation of bissulfamic acid-grafted on silica-coatednano-Fe3O4 particles (MNPs-TBSA), and their application as a retrievable heterogeneous acidiccatalyst for the green synthesis of 1, 4-Dihydropyridines and 2, 3-dihydroquinazolines is probed. This nanocatalyst is easily separated from the reaction mixture with the assistance of an externalmagnetic field and reuse for several runs without deterioration in catalytic activity. The morphology, structure, and size of magnetic nanoparticles were characterized via SEM, XRD, EDS, FT-IR andTGA/DTA. Eco-friendly and non-toxic condition, high yield and purity of the desired products, short reaction time along with the ease of the workup procedure outline the advantages of thesenew methodologies over the earlier ones.