فهرست مطالب

Advanced Journal of Chemistry, Section A
Volume:2 Issue: 2, Spring 2019

  • تاریخ انتشار: 1398/01/12
  • تعداد عناوین: 7
  • Sumitra Nain, Ruchi Singh, S Ravichandran * Pages 94-104

    Microwave is a convenient source of heating for organic synthesis. The heating is instantaneous and very specific. Nowadays Microwave assisted organic synthesis may consider all the previously heated reaction by this technique. The benefits of this organic synthesis by microwave increasingly making this technique more established worldwide. The various organic molecules may be quickly, efficiently, cleanly as well as economically synthesized by this technique. This article is mainly focusing on the importance of organic synthesis by microwave heating.

    Keywords: microwave heating, Organic synthesis, chemical reactions
  • Kingsley Ogemdi Iwuozor * Pages 105-127

    Wastewaters from chemical industries are characterized by the presence of heavy metallic ions, chemical contaminant and turbidity. Exposure to lead (Pb), for example, is recognized as a major risk factor for several human diseases, and the structure of industrial ecological systems have made exposure to Pb unavoidable for most people alive today. The removal of these toxic metals and contaminants from industrial wastewater is a matter of great interest in the field of water pollution, which is a serious cause of water degradation. Coagulation-flocculation is a widely used method for wastewater treatment especially if the wastewater is discharged into surface water. Coagulation/flocculation is a commonly used process in water and wastewater treatment in which compounds such as ferric chloride and/or polymer are added to wastewater in order to destabilize the colloidal materials and cause the small particles to agglomerate into larger settle able flocs. Therefore, the futuristic use as well as the present demerits of this process is necessary for the treatment of effluents.

    Keywords: Effluents, Coagulation, flocculation, Coagulants, Flocs
  • Hadi Noorizadeh, Abbas Farmany * Pages 128-135

    The adsorption features of amino functionalized superparamagnetic iron oxide nanoparticle/SiO2 for selective removal of arsenic in water is studied. Amino functionalized superparamagnetic iron oxide nanoparticle/SiO2 is synthesized and characterized with Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and electron microscope (SEM). FTIR shows amine group successfully attached to nanoparticle. XRD-diffraction pattern show that the magnetic phase of superparamagnetic nanoparticle is magnetite by inverse spinel crystal structure. SEM image was used to study the morphology of superparamagnetic nanoparticle. The adsorption capability of the nanoparticle was examined in batch system. The nanoparticle was used for removal of arsenic in aqueous media. Adsorption experimental data showed that the adsorption of arsenic on the nanoparticle is depended on pH and contact time.

    Keywords: As(III), Superparamagnetic iron oxide nanoparticle, SiO2-NH2, Adsorption
  • Kingsley Iwuozor * Pages 136-146
    This research was aimed at the qualitative and quantitative determination of three anti-nutritional factors (Oxalate, Phytate, and Tannins) present in five wine samples produced in Nigeria. The determination of tannin was done using Folin-Denis Spectrophotometric method, the determination of oxalate was done through three processes namely; digestion, oxalate precipitatin and permanganate titration. From the result obtained, it was revealed that the five wine samples actually contained these anti-nutritional factors and these compounds were present in amounts that were not toxic to the human health. Ingestion of the wine samples over a long period of time could increase the anti-nutritional content and cause serious health challenges that could affect the liver and kidney. Therefore sensitization on the harms of prolonged intake of these wine samples should be a priority to the government. Government should also impose a strict law that will checkmate manufacturers of these drinks so as to make sure that these drinks are properly treated.
    Keywords: Wine, Folin-Denis, tannin, Phytate, Oxalate
  • Adams Itodo *, Raymond Wuana, Bulus Emmanuel Duwongs, Davoe Danbok Bwede Pages 147-164
    Mining activities are one of the numerous ways by which man impacts on his environment. In this study, two non-destructive analytical techniques (XRF and XRD) were employed in the mineralogical characterization of Columbite-Tin ore and their contaminated soils. This investigates associated unnoticed minerals as well as the impact of mining on vicinity farmland soils on the Yelwa-Mbar mining site, Nigeria. The chemical characterization of Columbite ore using electron dispersive XRF revealed that most of the Columbite mineral deposits in the Plateau mining sites contain Niobium mineral in various proportions and vary from deposit to deposit depending on the geochemical composition of the minerals that formed the parent rock. Tin content as determined by ED-XRF impart that the ore can be utilized directly in the furnace because of its high cassiterite content (85.43%). The percentage elemental composition of soil around the mining vicinity unveiled the presence of Radionuclides K-40, Rubidium and Thorium in the soil. This is of great concern. The XRD mineralogical investigation of Columbite shows the presence of associated braunite, cassiterite, ilmenite, quartz, and zircon while the phase pattern for Tin ore confirmed the availability of cassiterite, magnetite and litharge. Pollution status based on contamination factor and geo-accumulation indices gave both radionuclides and heavy metal concentrations that depicts moderate to extreme contaminations.
    Keywords: Pollution Index, Geo-accumulation, Mineral, Soil, columbite, tin, Plateau
  • Simin Janitabar Darzi *, Niloofar Mohseni Pages 165-174
    Sol-gel synthesis of surfactant-templated nanostructured ceramic materials is usually carried out via controlled hydrolysis and condensation of a starting material in the presence of micelles of a polymer, followed by its removal by extraction or calcination. In this work, surfactant template sol-gel route for the synthesis of thorium dioxide gels using thorium nitrate and octyl phenol ethoxylate polymer as a structure directing agent was described, and the sinterability of the produced ThO2 powder (ThO2-S) was investigated in comparison with commercial one (ThO2-C). Prepared ThO2-S composed of micro and meso pores and exhibited high surface area as 31.23 m2/g and particle size as 15.1 nm. The produced powder ThO2-S was pressed and sintered to form the high density ThO2 pellet. The final grain size of the pellets reached below micrometer size. The calculated green and sintered densities of the fabricated pellets, and their microstructural characteristics studies, utilizing SEM images, show that this synthesizing route yielded a good sinterability of the synthesized ThO2 nanopowder at low temperature. Prepared ThO2-S sample and commercial ThO2 were sintered under the atmospheres “Ar” and “Ar-8%H2, and comparison of data from samples sintered under the both of two different atmospheres at 1500 °C, show that the atmosphere had no effect on density value. Furthermore, the green density of ThO2-S pellets is less than ThO2-C but the pellets which were fabricated from the ThO2-S have reached better sintered density than the pellets fabricated by ThO2-C.
    Keywords: ThO2, Sol Gel Process, Fuel pellet, Density, sinterability
  • Walter Efiok John, Ayi Anyama Ayi*, Chinyere Ayi Anyama, Providence Betelwhobel Ashishie, Bassey Enyi Inah Pages 175-183

    1-ethyl-3-methylimidazolium acetate (EMIMOAC) and 1-buthyl-3-methylimidazolium acetate (BMIMOAC) ionic liquids have been used as a solvent and stabilizing agent in an attempt to prepare cobalt nanoparticles via chemical reduction method. The SEM and UV-Vis techniques confirm the formation of nanoparticles. XRD reveals the nanocrystalline nature of the products with average crystallite size of 27.5 and 24.1 nm for CoEMIMOAC and CoBMIMOAC, respectively. The SEM and EDAX morphological/atomic weight ratio analyses show not much difference between the nanocrystals formed in EMIMOAC or BMIMOAC. These results indicate that the cationic part of the ionic liquid did not play significant role during nucleation and growth of the particles. The zone of inhibition of CoEMIMOAC obtained against Staphylococcus aureus and Escherichia coli are 23 and 14 mm, respectively whereas that of CoBMIMOAC against the bacterial under investigation is 15 mm. The synthesized nanocrystals have therefore demonstrated great potentials as nanodrugs in the treatment of infections caused by gram-positive microorganisms.

    Keywords: nanocrystals, Ionic Liquids, Chemical reduction, Nanoparticles, Antimicrobial activities