114 research outputs found

    Synthesis, characterization and microstructural evaluation of ZnO nanoparticles by William-Hall and size-strain plot methods

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    ABSTRACT. At various calcination temperatures 450, 550 and 650 °C, zinc oxide nanoparticles were produced. Calcinated ZnO has high surface area as the BET was 119.12 m2g–1 and the average particle radius was calculated to be 1.16 nm. The dimension of crystallites and straining in ZnO nanoparticles' diffraction peaks remained measured. The Williamson–Hall (W–H) technique besides the size–strain approach stayed used. For each of XRD reflection peaks, physical characteristics like strain and stress were computed. Towards regulate the magnitude of crystallites, the Williamson–Hall (W–H) approach besides the size–strain technique are used that is good agreement with the size that determine from SEM as it was 22.6, 26.6 and 32.6 nm for ZnO calcinated at 450, 550 and 650 oC, individually. Using the W–H plot to modify the subversion shape, assuming an unvarying distortion model (UDM), unvarying stress deformation model (USDM), unvarying deformation energy density model (UDEDM), and The size–strain plan (SSP) approach was used to determine this. The SEM and Scherrer methods match well with the crystal size of ZnO NPs determined using W–H plots and the SSP technique.     KEY WORDS: Zinc oxide nanosphere, Calcination, Physical characterization, W–H investigation, SSP technique Bull. Chem. Soc. Ethiop. 2022, 36(4), 815-829.                                                           DOI: https://dx.doi.org/10.4314/bcse.v36i4.8                                                       &nbsp

    Variables Affecting the Mothers Access to Quality Care during Childbirth using the Neural Networks and Logistic Regression Models

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    Quality pregnancy and birth care is crucial in reducing maternal and child mortality in Egypt, requiring both supply and demand interventions. Using data from the Egypt Demographic Health Survey 2014, a neural networks and logistic regression models were built to determine demographic, social, and economic determinants affecting mothers access to care during childbirth. The study found that mothers working status had a significant impact on access to care, with an inverse relationship. Logistic regression outperformed neural networks in analyzing the relationship between explanatory variables and mothers access to care during childbirth

    Hydrophobic Polymers Flooding

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    Crude oil and other petroleum products are crucial to the global economy today due to increasing energy demand approximately (~1.5%) per year and significant oil remaining after primary and secondary oil recovery (~45-55% of original oil in place, OOIP), which accelerates the development of enhanced oil recovery (EOR) technologies. Polymer flooding through hydrophobically associated polyacrylamides (HAPAM) is a widely implemented EOR-technique, so they attracted much attention on both academic and industrial scales. Hydrophobically associating polyacrylamide (HAPAM) prepared by free radical emulsion polymerization of acrylamide (AM) monomer, divinyl sulfone as hydrophobic crosslinked moiety and surfmers, to chemically anchor a surfmer and hydrophobic crosslinker moiety onto the back bone of acrylamide chain. After that, polymeric nanocomposite was prepared through copolymerization of prepared HAPAM with different molar ratios of silica nanoparticles through one shot synthesis. Rheological properties for the prepared composites were evaluated. Wettability evaluation carried through quantitative and qualitative techniques where the results indicate novel polymers ability to alter rock wettability from oil-wet to water- wet

    PROTECTIVE EFFECTS OF ZINGIBER OFFICINALE AGAINST CARBON TETRACHLORIDE INDUCED LIVER FIBROSIS

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    Objective: Liver plays a pivotal role in regulating various physiological processes in the body such as metabolism, secretion, and storage. It has a great capacity to detoxify toxic substances and synthesize useful principles. The current study was designed to investigate the possible protective effects of Zingiber officinale (ginger) extract on liver fibrosis induced by carbon tetrachloride (CCl4) in rats.Methods: The animals were divided into four groups with eight rats in each. To induce liver fibrosis, Wistar albino rats received CCl4 (2 ml/kg diluted in corn oil) twice weekly for eight weeks. Rats were concurrently treated with Z. officinale extract at two different doses (300 and 600 mg/kg/day).Results: CCl4 ­­induced liver injury characterized by fibrotic changes, degenerated hepatocytes and focal accumulation of inflammatory cells. In addition, CCl4 administration produced a significant increase in serum aminotransferases, lipids, liver lipid peroxidation and nitric oxide. The hepatoprotective effects of Z. officinale extract were evidenced by the significant decrease in serum aminotransferases and liver lipid peroxidation. Further, concurrent treatment with either dose of Z. officinale enhanced liver glutathione and enzymatic antioxidant defenses.Conclusion: Z. officinale showed a marked hepatoprotective effect against CCl4–induced liver fibrosis and injury through the abolishment of oxidative stress and potentiation of the antioxidant defense system.Keywords: Antioxidant, Ginger, Fibrosis, Oxidative stres

    Contribution to the understanding of the Ionian Basin sedimentary evolution along the eastern edge of Apulia during the Late Cretaceous in Albania

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    Integrated in the peri-Adriatic domain, the Ionian Basin extended along a NW-SE direction during the Late Cretaceous, limited on its sides by the Apulian and the Kruja platforms. The basinal/slope succession was studied in seven outcrops exposed in the Albanian fold-and-thrust belt. Sedimentological investigations, supported by bio- and chronostratigraphy were performed on calcareous Upper Cretaceous hemipelagites, gravity-flow deposits and slumps. The western part of the basin was studied, revealing a strong influence of the Apulian margin, alternatively shedding sediment basinward, by means of a tectonically controlled edge. The Late Albian to Cenomanian period is characterized by the settling of muddy debrites along the margin. A deep basinal environment characterizes this period which prolongs until the Santonian, with no significant influx of the platform basinward. This sedimentary setting abruptly changed at the end of the Santonian, with an important influx derived from both platforms. Coarsening and thickening upward sequences show a progressive increase in sediment shedding during the Campanian. The Late Campanian-Early Maastrichtian period points out a major change on the resedimentation processes with the settling of several slumped units reworking thick sediment packages. The latter can be traced along the Apulian margin, testifying of instabilities along the edge of Apulia

    Efficient adsorption of Rhodamine B using a composite of Fe3O4@zif-8: Synthesis, characterization, modeling analysis, statistical physics and mechanism of interaction

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    ABSTRACT. The utilization of a metal organic framework (ZIF-8) modified by Fe3O4 nanoparticles was used to accomplish adsorption of Rhodamine B (RB) from aqueous solutions. SEM, XRD, IR, and BET analyses were all used to characterize the composite (Fe3O4@ZIF-8). The surface area of this adsorbent was 478.4 m2/g. X-Ray diffraction spectroscopy was used to detect surface modification utilizing electron microscopy (SEM) scanning with 48 nm in diameter average particle size according to a statistical physics method. Fe3O4@ZIF-8 appears to have dispersive interactions and pore characteristics, according to quantum chemistry simulations. On the adsorption of RB, the influences of contact time, adsorbent quantity, dye concentration, and temperature were studied. The Langmuir and Freundlich adsorption isotherm models were used to study the adsorption isotherms. Anticipated overall adsorption potential was 647.5 mg/g, with a zero-charge point (pHPZC) of 4.3. The adsorption isotherm was fitted using Langmuir whereas pseudo second order was used to match the kinetics. Energy of adsorption (Ea) is 28.7 kJ/mol, indicating a chemisorption phase. The adsorption process is endothermic and unpredictable, according to thermodynamic experiments. It was also looked into using ethanol as a solvent in the desorption of deposited cationic dye.   KEY WORDS: Fe3O4@ZIF-8, Rhodamine B, Adsorption models, Thermodynamics   Bull. Chem. Soc. Ethiop. 2023, 37(1), 211-229.                                                                DOI: https://dx.doi.org/10.4314/bcse.v37i1.17                                                     &nbsp

    Preliminary Investigation of the Corrosion Behavior of Proprietary Micro-alloyed Steels in Aerated and Deaerated Brine Solutions

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    The corrosion performance of fairly new generation of micro-alloyed steels was compared in different concentrations of aerated and deaerated brines. Electrochemical polarization, weight loss and surface analyses techniques were employed. The results showed a threshold of corrosion rate at 3.5 wt.% NaCl in both aerated and deaerated solutions. The average corrosion current density for steel B, for example, increased from 1.3 µA cm¯² in 1 wt.% NaCl to 1.5 µA cm¯² in 3.5 wt.% NaCl, but decreased to 1.4 µA cm¯² in 10 wt.% deaerated NaCl solutions. The aerated solutions exhibited an average of over 80% increase in corrosion current density in the respective concentrations when compared with the deaerated solution. These results can be attributed to the effects of dissolved oxygen (DO) which has a maximum solubility in 3.5 wt.% NaCl. DO as a depolarizer and electron acceptor in cathodic reactions accelerates anodic metal dissolution. The difference in carbon content and microstructures occasioned by thermo-mechanical treatment contributed to the witnessed variation in corrosion performance of the steels. Specifically, the results of the various corrosion techniques corroborated each other and showed that the corrosion rate of the micro-alloyed steels can be ranked as CR[Steel A] < CRₓ₆₅ < CR[Steel B] < CR[Steel C]

    ASTER, ALI and Hyperion sensors data for lithological mapping and ore minerals exploration

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