478 research outputs found

    Sulphatisation and Sulphidisation for hydro-metallurgical extraction of main constituents of a local ilmenite Ore

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    ILMENITE ores occur in UAR in large quantities, const- ituting two main reserves . The first, estimated to be about 10 million tons, occurs at Abu Ghalaga (AG) in the south-eastern desert, and the second comprises one of the chief constituents of beach placers, called black sands (BS), which are deposited on the shores of the Nile delta, especially at Rosetta and El-Arish. According to previous studies' AG ilmenite occurs in the form of lenticular , vein-like bodies intimately associated with metagabbro. The chief lens is about 300 m long, 150 m wide and 45 to 100 m thick

    Formulation, evaluation and optimization of miconazole nitrate tablet prepared by foam granulation technique

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    The aim of our study was to utilize novel foam granulation technique in formulation of miconazole nitrate; a model hydrophobic drug as oral disintegrating tablets "ODT" particularly to enhance its bioavailability. Foam granulation technique has additional advantages over the other traditional granulation technique since; it enhances the granulation process and produce acceptable tablets. Fractional factorial design was used to investigate the effect of formulation and processing variables on the prepared miconazole ODT. The prepared granules were evaluated by measuring their density, flowability, granules size and shape, and granules wetting time. The quality attributes of the prepared tablets; drug content, tablet thickness, uniformity of weight, tablet tensile strength, friability, disintegration, and dissolution were also evaluated. The results indicated that, the prepared granules showed acceptable characteristics and is significantly affected by the disintegrant type, urea concentration, and the lubricant type. The quality attributes of the tablets were not affected by the processing parameters. From the prepared formulas; F20, F19, F12, and F20 displayed 18, 35, 35, and 40 seconds disintegration time respectively and the percent of dissolution after 15 minutes ranged from 94.4-100%. These results ascertained that foam granulation technique fulfill the requirement in preparation of miconazole ODT. Key words: miconazole nitrate, foam granulation, oral disintegrating tablet

    Time Trends of Polybrominated Diphenyl Ethers (PBDEs) in Antarctic Biota

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    Polybrominated diphenyl ethers (PBDEs) are emerged contaminants that were produced and used as flame retardants in numerous consumer and industrial applications for decades until banned. They remain ubiquitously present in the environment today. Here, a unique set of \u3e200 biotic samples from the Antarctic was analyzed for PBDEs, including phytoplankton, krill, fish, and fur seal milk, spanning several sampling seasons over 14 years. PBDE-47 and -99 were the dominant congeners determined in all samples, constituting \u3e 60% of total PBDEs. A temporal trend was observed for Sigma 7PBDE concentrations in fur seal milk, where concentrations significantly increased (R-2 = 0.57, p \u3c 0.05) over time (2000-2014). Results for krill and phytoplankton also suggested increasing PBDE concentrations over time. Trends of PBDEs in fur seal milk of individual seals sampled 1 or more years apart showed no clear temporal trends. Overall, there was no indication of PBDEs decreasing in Antarctic biota yet, whereas numerous studies have reported decreasing trends in the northern hemisphere. Similar PBDE concentrations in perinatal versus nonperinatal milk implied the importance of local PBDE sources for bioaccumulation. These results indicate the need for continued assessment of contaminant trends, such as PBDEs, and their replacements, in Antarctica

    Digital Twins Approaches and Methods Review

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    © 2023 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. This is the accepted manuscript version of a conference paper which has been published in final form at https://doi.org/10.1109/ITC-Egypt58155.2023.10206196This paper investigates the recent advances in Digital Twin technologies. The aim is to compare the approaches, available open source and proprietary technologies and methods, their features, and their integration capabilities. The motivation is to enable better design decisions based on the available literature and case studies. Various tools for 3D reconstruction and visualisation, IoT and sensor integration, Physical simulations and other complete platforms provide complete solutions. A conclusion of current challenges and future work identified that the lack of standardisation and interoperability makes the lifetime of a digital twin short, with a high cost and time to build and rebuild if required

    Pharmacodynamic and Pharmacokinetic Studies on Tetracycline Hydrochloride in Rabbits

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    Tetracycline is one of the most important groups of antibiotics that have harmful effects on the consumers, therefore the public health safety against its residues represents a significant issue. This study aimed to estimate the effect of tetracycline hydrochloride on some hematological parameters, kidneys function tests as well as liver and breast muscle enzymes with special reference to the supposed withdrawal time of this drug in different rabbits’ tissues (kidney, liver and muscles), following oral dose of tetracycline using High Performance Liquid Chromatography. Tetracycline was administrated to eighteen rabbits directly into the stomach at a dose of 35 mg/kg BW once daily for five successive days. Samples were collected on the 1st, 3rd, 7th, 14th, 21st and 28th days after the last oral dose. The results revealed that, tetracycline caused a significant increase in the uric acid, urea, creatinine, alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) activities with no significant changes in the hematological parameters when compared with the control group. The residues remained in the liver and kidney for 7 days, while in muscles for 3 days only after the last oral dose of the drug. In conclusion, the disturbances in the biological parameters occurred by tetracycline administration in rabbits was transient and returned to normal after 7 days of last treatment. The withdrawal time of tetracycline was 14 days from the rabbit's tissues

    Novel polysaccharide hybrid scaffold loaded with hydroxyapatite: Fabrication, bioactivity, and in vivo study

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    © 2018 Elsevier B.V. The main goal of this study was to produce a novel porous scaffold for rapid in vivo bone healing behavior. Lyophilization technique was used to produce this highly porous hybrid scaffold from Na-alginate (S) and hydroxyethylcellulose (HEC) impregnated with different concentration of hydroxyapatite (HA). After cross-linking the scaffolds, their incubation was carried out in simulated body fluid (SBF) for 4 weeks at 37 °C to investigate their bioactivity. A number of techniques were employed (e.g., XRD, FTIR, SEM, EDX, and texture analyzer) to characterize the designed scaffolds. It was observed that the mechanical properties of the scaffolds increase deformation energy (182 ± 16 J/m3) and rigidity gradient (19.44 ± 0.85 Pa) after loading with HA. Furthermore, the scaffolds were implanted in femur critical size defects (2 mm) of adult male Wistar rats for 6 weeks. In vitro and in vivo analyses demonstrated impressive bioactivity and biocompatibility for the prepared scaffolds, especially those containing HA. Based on the obtained results we conclude that the designed scaffolds are promising solutions for bone regeneration applications

    Spatial Distribution, Air-Water Fugacity Ratios and Source Apportionment of Polychlorinated Biphenyls in the Lower Great Lakes Basin

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    Polychlorinated biphenyls (PCBs) continue to be contaminants of concern across the Great Lakes. It is unclear whether current concentrations are driven by ongoing primary emissions from their original uses, or whether ambient PCBs are dominated by their environmental cycling. Freely dissolved PCBs in air and water were measured using polyethylene passive samplers across Lakes Erie and Ontario during summer and fall, 2011, to investigate their spatial distribution, determine and apportion their sources and to asses their air–water exchange gradients. Average gaseous and freely dissolved ∑29 PCB concentrations ranged from 5.0 to 160 pg/m3 and 2.0 to 55 pg/L respectively. Gaseous concentrations were significantly correlated (R2 = 0.80) with the urban area within a 3−20 km radius. Fugacity ratios indicated that the majority of PCBs are volatilizing from the water thus acting as a secondary source for the atmosphere. Dissolved PCBs were probably linked to PCB emissions from contaminated sites and areas of concern. Positive matrix factorization indicated that although volatilized Aroclors (gaseous PCBs) and unaltered Aroclors (dissolved PCBs) dominate in some samples, ongoing non-Aroclor sources such as paints/pigments (PCB 11) and coal/wood combustion showed significant contributions across the lower Great Lakes. Accordingly, control strategies should give further attention to PCBs emitted from current use sources
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