273 research outputs found

    Assessment of natural radionuclides and heavy metal concentrations in marine sediments in view of tourism activities in Hurghada city, northern Red Sea, Egypt

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    The specific activity of 40K, 232Th and 226Ra in marine sediment samples collected from National Institute of Oceanography and Fisheries (NIOF) and Safier Hotel area in Hurghada city (the most important regions in Egypt), were measured by gamma ray spectrometry using NaI(Tl) detector. The values of specific activity varied from 7 ± 1 Bq kg-1 to 53 ± 4 Bq kg-1, 6 ± 1 Bq kg-1 to 32 ± 6 Bq kg-1, and from 167 ± 11 Bq kg-1 to 1120 ± 63 Bq kg-1 for 226Ra, 232Th and 40K, respectively. The heavy metals have been measured and analysed by atomic absorption spectrometer. The major range values of heavy metals concentrations in marine sediment samples were: Cu (10.5-78.0 μg g-1), Zn (21-150 μg g-1), Pb (30-53 μg g-1), Cd (2.50-4.00 μg g-1), Fe (5100-13150 μg g-1), Mn (118-298 μg g-1), Ni (17-36 μg g-1) and Co (16-18 μg g-1). The total organic matter (TOC) and carbonates (CaCo3) distribution have been measured at some locations. Also, the frequency distribution and the value of (232Th/226Ra), (232Th/40K) and (226Ra/40K) ratio for all measured samples were determined. Additionally, evaluations have been made of the radiological hazards and the results are diagrammed by Surfer program in maps. © Penerbit Universiti Sains Malaysia, 2019

    The Differential Efficiency of Chlorella vulgaris and Oscillatoria sp. to Treat the Municipal Wastewater

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    The utilization of microalgae to treat wastewater becomes an alternative biological wastewater treatment technique worldwide because of its low cost and environmental clean. Chlorella vulgaris and Oscillatoria sp. were cultured in municipal wastewater under controlled laboratory conditions with continuous light illumination and aeration. Physical properties (pH, TDS and Salinity), and nutrient contents (ammonia, nitrite and total phosphorus)were measured in the raw wastewater. Growth rates of the cultured species in terms of optical densities and cell counts, nutrient salts removal efficiencies were measured during the experimental durations after; 24, 48, 72, 96 , 120 and 144hrs. Lipids, proteins and carbohydrates contents were also evaluated after 144hrs. The recorded optical density of Chlorella vulgaris was 0.188±0.01 at 680 nm and 0.17±0.01 at 750 nm after 24hrs then increased to 1.45±0.002 at 680nm and 1.43±0.01 at 750nm at the end of 120hrs, meanwhile the optical density of Oscillatoria sp. was increased from 0.132±0.01 at 680 nm and 0.102±0.01 at 750 nm after 24hrs to 1.054±0.004 at 680 nm and 0.99±0.002 at 750 nm at the end of 120hrs of the experiment. On the other hand, the cell count of Chlorella vulgaris was enriched from 6.8±2.2 cell/ml after 24hrs to 720±120 cell/ml at the end of 120h of the culturing. Overall, efficiencies of nutrients removal were 99.426%, 100% and 82.211% for ammonia, nitrite and total phosphorus respectively at the end of 120hrs of Chlorella vulgaris culturing, while Oscillatoria sp nutrient removal efficiencies recorded 98.125%, 100% and 84.718% for ammonia, Nitrite and total phosphorus respectively. Chlorella vulgaris biomass was estimated 26.66±7.5% lipid 35.1±1.6% protein and 29.34±3.25% carbohydrate, however Oscillatoria sp. biomass was estimated 11.76±0.79% lipids, 32.9±1.92% protein and 27.36±3.78% carbohydrates. Keywords: municipal Wastewater, Chlorella vulgaris, Oscillatoria sp., nutrient removal, biochemical parameters

    Some New Exact Solutions of Jacobian Elliptic Functions in Nonlinear Physics Problem

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    Abstract:An extended mapping method with symbolic computation is developed to obtain some new periodic wave solutions in terms of Jacobin elliptic function for nonlinear elastic rod equation arising in physics.As a result,many exact travelling wave solutions are obtained which include Jacobian elliptic functions solutions,combined Jacobian elliptic functions solutions and triangular function solutions.Solutions in the limiting cases have also been studied.It is shown that the mapping method provides a very effective and powerful mathematical tool for solving nonlinear evolution equations in physics

    4-(1H-Benzimidazol-2-ylmeth­oxy)-3-eth­oxy­benzaldehyde trihydrate

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    In the title compound, C17H16N2O3·3H2O, the dihedral angle between the mean planes of the benzene and benzimidazole systems is 26.2 (3)°. These groups are slightly twisted around the eth­oxy­methane unit [C—C—O—C torsion angle = 177.64 (15)°]. The crystal packing is stabilized by N—H⋯O, O—H⋯N and O—H⋯O hydrogen-bond inter­actions involving the water mol­ecules. Weak π–π stacking inter­actions [centroid–centroid distances = 3.7943 (7), 3.6919 (13) and 3.7533 (14) Å] contribute to the mol­ecular stability

    (2E)-3-{4-[(1H-1,3-Benzimidazol-2-yl)meth­oxy]-3-eth­oxy­phen­yl}-1-(4-bromo­phen­yl)prop-2-en-1-one monohydrate

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    In the title compound, C25H21BrN2O3·H2O, the benzimidazole fragment and the water mol­ecule of crystallization are each disordered over two sets of sites of equal occupancy. The dihedral angles between the least-squares planes of the benzimidazole and the 3-eth­oxy- and 4-bromo­benzene rings are 86.9 (6) and 85.1 (1)°, respectively in one disorder component. The crystal packing is stabilized by inter­molecular O—H⋯O, O—H⋯N and N—H⋯N hydrogen bonds, which link the mol­ecules into chains along the a axis

    Radiation Hazards and the Cancer Risk Assessments in the Sediments of Timsah Lake, Egypt

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    Timsah Lake is one of the most fish productive lakes in Egypt. It is located at the midpoint of Suez Canal with surface area of about 16 km2. The lake receives about 833,000 m3daily of wastewater and sewage wastes from agriculture, industry and domestic drains. The activity concentrations of the natural radionuclides; 238U, 232Th and 40K were measured using gamma-ray spectrophotometer at 24 stations covering the whole area of the lake and the Western Bay. The average activities of 238U, 232Th and 40K were; 21.66 ± 11.20, 21.42 ± 11.68 and 200.30 ± 141.10 Bq/kg respectively. The averages of radiation hazard parameters; the absorbed and effective dose rate (D), the annual effective dose equivalent (AEDE), radium equivalent (Raeq), the external hazard index (Hex) and the representative level index (Iγr) were; 30.85 nGy h-1, 37.84 μSv/y, 67.02 Bq/kg, 0.18 (lower than the unity) and 0.23 respectively. The distribution patterns showed significant high variations in the radionuclides activities and the hazard parameters between the investigated stations. The Western Bay stations and the path zone interlinked between the bay and the lake showed the high radionuclide activities and high radiation hazards indicating to the sewage wastes and wastewater runoff are the essential sources of the high natural radionuclide activities and radiation hazards. The average of the excess lifetime cancer risk (ELCR) was 132.43 × 10-6significantly lower than the worldwide average. The highest recorded level of ELCR was reached 308.38 × 10-6observed in the interlink zone between the bay and the lake away from fishing stations and recreational zones. Statistical analyses indicated that the radionuclides 238U and 232Th are the sources of the elevated radiation hazards with nearly equal intensities. © 2020. All Rights Reserved

    Study of the Electrical Properties and Swelling Mechanism in Compressed Butyl Rubber Loaded with Carbon Black

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    The dependence of both electrical conductivity "σ" and dielectric constant "ε" for samples containing different carbon black concentrations were studied at different loads. It was found that, "σ" and "ε" are nearly load independent at low concentration, however, they change at higher concentration of carbon black. Swelling of the samples in both benzene and kerosene was measured, and found to be dependent on both carbon black concentration and the type of solvent used. The diffusion coefficient, penetration rate and the molecular mass were calculated

    Approaching ancient disease from a One Health perspective: Interdisciplinary review for the investigation of zoonotic brucellosis

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    Today, brucellosis is the most common global bacterial zoonosis, bringing with it a range of significant health and economic consequences, yet it is rarely identified from the archaeological record. Detection and understanding of past zoonoses could be improved by triangulating evidence and proxies generated through different approaches. The complex socio‐ecological systems that support zoonoses involve humans, animals, and pathogens interacting within specific environmental and cultural contexts, and as such there is a diversity of potential datasets that can be targeted. To capture this, in this paper we consider how to approach the study of zoonotic brucellosis in the past from a One Health perspective, one which explicitly acknowledges the health link between people, animals and environments (both physical and cultural). One Health research is explicitly interdisciplinary and conceptually moves away from an anthropocentric approach, allowing the component parts to be considered in holistic and integrated ways to deliver more comprehensive understanding. To this end, in this paper we review the methods, selected evidence and potential for past brucellosis identification and understanding, focussing on osteological markers in humans and animals, historical, biomolecular and epidemiological approaches. We also present an agenda and potential for future research
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