949 research outputs found

    Stabilization of active acetylene by-product via sequestration of co\u3csub\u3e2\u3c/sub\u3e

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    © 2020 Taylor & Francis Group, London, UK. The rising rates of carbide lime waste (CLW), the by-product of acetylene production, cause environmental problems and need for the repurposing of the said material. The high content of calcium in such by-products (60–80%) is the main reason for its utilization in CO2 sequestration. This study focused on using of CLW to form simple, reliable, cost-efficient process, applying direct solid-liquid-gas carbonation reaction, which consists of bubbling CO2 gas through an aqueous slurry of slaked CLW with different solid /water ratios. The experimental conditions were adjusted for maximum carbonation efficiency. Experimental results indicated that CLW has the potential to store CO2 in the form of stable carbonates. Considering the total calcium content, an amount of 0.5833 kg CO2 /kg CLW was achieved. The influence of solid/water ratio on the precipitation of calcium carbonate was investigated using SEM that showed a difference in crystal carbonate sizes and morphologies

    The effect of serum angiotensin II and angiotensin II type 1 receptor gene polymorphism on pediatric lupus nephritis

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    Background: Angiotensin II (Ang II) is found to perpetuate inflammation and visceral damage in systemic lupus erythematosus (SLE). It mediates most of its actions through Ang II receptor type I (AT1) whose gene polymorphism A1166C (CC genotype) seems to have pathogenic effects. Objective: To measure serum Ang II and the frequency of AT1 receptor CC genotype among a group of Egyptian patients with pediatric onset lupus nephritis (pLN). Methods: This is a case-control cross sectional study which included 24 patients with pLN and 24 age and sex-matched healthy subjects as controls. Clinical evaluation and routine laboratory markers for SLE patients were done. SLE disease activity index (SLEDAI) and the British Isles Lupus Assessment Group (BILAG)-2004 renal score were measured. Serum Ang II was measured by enzyme linked immunosorbent assay and detection of ATI receptor CC genotype by polymerase chain reaction were done for both patients and controls. Results: Patients had significantly higher serum Ang II than the controls (p=0.0001). The frequency of AT1 receptor CC genotype was significantly higher among patients as compared to the control group (p=0.008). Both serum Ang II and AT1 receptor CC genotype were comparable between patients with proliferative LN class III and IV and those with LN class II (p>0.05). Serum Ang II did not correlate significantly with SLEDAI or BILAG-renal score (p>0.05). Conclusion: Serum Ang II and AT1 receptor CC genotype seem to have pathogenic role in pLN but with no deleterious effects on the phenotype of LN for further assessment.Keywords: Lupus nephritis; Angiotensin II; Angiotensin II type 1 receptor; Polymorphism; Pediatrics

    Residual and Past Entropies of Concomitants from Lai And Xie Extensions of Case-II of Generalized Order Statistics and its Dual

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    In this article, we consider a new extensions of Morgenstern family is Lai and Xie extensions and discuss their concomitants for case-II of generalized order statistics and case-II of dual generalized order statistics. Additionally, recurrence relation between moments is found for the recommended models. We have also derived the expression for the joint distribution of concomitants for case-II of generalized order statistics and its dual. The residual and past entropies are shown last

    Seminavis aegyptiaca sp. Nov., a new amphoroid diatom species from estuary epilithon of the river–nile damietta branch, Egypt

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    During a recent floristic–taxonomic study on the algal flora, including diatoms, from the estuary of the Damietta Branch of the Nile in Egypt, an interesting epilithic diatom species belonging to the genus Seminavis (Naviculaceae) was collected and investigated using both light and scanning electron microscopy. This new diatom species shares morphologically some taxonomic diagnostic features with other related taxa such as S. insignis, S. robusta, and S. ventricosa. However, it still differs by having ventral central striae that are shorter and more or less straight in the middle of the smaller frustules to be clearly radiate in the larger ones and then become geniculate and only radiate near the poles, the central raphe endings are externally more distantly spaced than in the similar species, the elongate central nodule is internally less prominent, and the areola density is much denser. Therefore, we here describe it as Seminavis aegyptiaca sp. nov. Hydrochemical analyses revealed that S. aegyptiaca commonly inhabits typical marine, with a weak tendency towards brackish water, habitats. It was found to be tolerant to meso–eutrophic, nutrient–enriched conditions, based on the data available on seasonal concentrations of N and P compounds. These findings not only contribute to the inventory of Egyptian diatoms, but also increase our understanding of the autecology and distribution of this relatively poorly–known diatom genus

    Geochemical characterization of recent Nile Delta inner shelf sediments: Tracing natural and human-induced alterations into a deltaic system

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    The present study deals with the geochemical changes observed along Nile Delta inner shelf sediments over a period of 20 years (1995–2015). Major, minor, and trace constituents as well as rare earth elements (REE) were investigated in the surface sediments collected from seven transects along the inner shelf on five years intervals. Geochemical composition of sediments in Nile Delta inner shelf exhibits continuous changes over time due to the depositional and sediment transport processes. The sediments are generally enriched with Fe and Ti oxides, as well as Ta, Nb, Y in comparison to the Upper Continental Crust (UCC). These alterations signify the impact of processes such as erosion and sediment transport, as well as the impact of anthropogenic interferences such as damming the Nile River Flow. The reduction of the sediment input from the Nile River has somehow altered the geochemical signature of the inner shelf sediments. The REE patterns indicate weathering in areas subjected to erosion, while trace elements and major oxides spatial and temporal distributions concentrate eastwards under the influence of the easterly sediment transport pattern. Nile Delta inner shelf presented a typical case for understanding the link between geochemistry and sedimentary processes in nearshore and deltaic systems

    Arabic gum acacia improves diabetic peripheral neuropathy in rats: a biochemical and histopathological evidence

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    Background: Diabetic peripheral neuropathy (DPN) is a frequent complication of diabetes mellitus and unfortunately, its present therapeutic alternatives are exceptionally poor. Objectives of this study was to assess the antidiabetic, antioxidant and hypolipidemic action of Gum Arabic (GA) and its role in promoting the functional recovery from diabetic neuropathy developed in in an experimental model of diabetic neuropathy.Methods: Sixty adult male Sprague-Dawley rats were utilized and randomly assigned into six groups (n= 10); control, Arabic gum-treated, untreated diabetic, diabetic received metformin, diabetic received metformin and B12 vitamin and diabetic received metformin, B12 vitamin and AG. Locomotor activity and hyperalgesia were assed at the end of the study. Fasting and two hours post-prandial blood glucose, serum insulin levels, lipid Profile, oxidants/antioxidants parameters were assessed in the blood. Sciatic nerve was assessed histopathologically.Results: The locomotor activity of the untreated diabetic rats was significantly (p<0.001) reduced compared to the control group while it was significantly increased in all treated groups. The lipid profile and Malondialdehyde were significantly improved in all treated groups. Levels of CAT, GSH, SOD, GPx were significantly decreased in untreated diabetic group compared to the control while they were significantly increased in all treated groups compared to the untreated diabetic group. Sciatic nerve fibers of untreated diabetic rats showed degenerated axons with dilated myelin sheaths and degenerated Schwann cells. The nerve had significantly fewer fiber compared to the control. These changes were alleviated in all the treated groups specifically that received metformin, vitamin B12 and GA.Conclusions: It could be concluded that Arabic gum had hypoglycemic, antioxidant and hypolipidemic activity and had a protective effect on diabetic neuropathy. Based on this it is recommended that human clinical trials are necessary to prove this therapeutic effect

    Effect of different treatments on germination of Romi red grape seeds

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    Germination of seeds required a stratification period either at cold (5 ± 1 °C) or warm (18 ± 1 °C) conditions. Besides, production of normal seedlings (seedlings with plumule) needed stratification of at least 60 d. Cold stratification treatments increased pronouncedly the percentages of seed germination and normal seedlings when seeds were first subjected to warm stratification conditions. Soaking the seeds in IAA, IBA or Ethrel at different concentrations before sowing failed completely to produce normal seedlings. Conversely, the best results with respect to germination i;ercentage and normal seedlings were obtained with GA-, especially at 5000 ppm, followed by thiourea and kinetin. Applying GA3 to seeds immediately before stratification was more effective than adding it after stratification.Der Einfluß verschiedener Behandlungsbedingungen auf die Samenkeimung bei der Rebsorte Romi redDie Samen der Rebsorte Romi red keimten nur nach Stratifikation, entweder unter Kälte- oder unter Wärmebedingungen (5 ± 1 °C bzw. 18 ± 1 °C). Normale Sämlinge, d. h. solche mit Plumula, entwickelten sich nur bei einer Stratifikationsdauer von mindestens 60 d. Durch Kaltstratifikation wurde der Anteil keimender Samen und normaler Sämlinge bedeutend erhöht, wenn die Samen zuvor warmstratifiziert worden waren. Das Einweichen der Samen vor der Aussaat in unterschiedlichen Konzentrationen von IAA, IBA oder Ethrel förderte die Bildung normaler Sämlinge in keiner Weise. Umgekehrt wurden im Hinblick auf die Samenkeimung und die Bildung normaler Sämlinge die besten Ergebnisse mit GA3, vor allem in der Konzentration von 5000 ppm erzielt; auch Thioharnstoff und Kinetin zeigten einen positiven Einfluß. GA3-Behandlung der Samen unmittelbar vor der Stratifikation war wirksamer als danach

    Crystal structure of 3-tert-butyl-3-hydroxy-1,3-dihydro-2H-pyrrolo[3,2-c]pyridin-2-one, C11H14N2O2

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    Abstract C11H14N2O2, orthorhombic, P212121 (no. 19), a = 7.5411(2) Ă…, b = 11.5148(2) Ă…, c = 12.5370(2) Ă…, V = 1088.64(4) Ă…3, Z = 4, R gt (F) = 0.0301, wR ref (F 2 ) = 0.0826, T = 296 K.</jats:p

    Amelioration of The Dielectric Properties of Ceramic Insulators Using Nano-alumina

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    Outdoor HV porcelain insulators face various environmental stresses that cause their degradation. Consequently, amelioration of their insulating properties becomes a target of recent researches to survive higher voltage levels. Investigating the impact of the addition of 0, 5, 10, and 15 wt. % nano- alumina (NA) on the dielectric and physical characteristics of porcelain materials at elevated sintering temperatures is the aim of this study. Porcelain specimens were synthesized from kaolin, feldspar, and quartz as available low-cost raw materials. The specimens were sintered at 1100, 1200, 1300, and 1400°C for 2 h. For some specimens, the microstructure and phases formed were identified using scanning electron microscopy and X-ray diffraction techniques. The changes that occur upon heating (include melting, phase transition, sublimation, and decomposition) were identified by Differential Thermogravimetric Analysis. The dielectric strength, relative permittivity, and loss tangent of different samples were measured at a large scale of frequencies. Breakdown strength values of different samples were verified by applying the Finite Element Method. The best electrical and physical properties were achieved at 1300ºC. At this temperature the porcelain sample containing 5 wt. % NA presented optimum physical characteristics as well as good insulating properties assent the feasibility of producing electro-technical porcelai

    Methyl N-(2-bromo-4-chlorophenyl)carbamate

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    In the title molecule, C8H7BrClNO2, the bromochlorophenyl ring is inclined to the methylcarbamate unit by 32.73 (7). In the crystal, N—HO hydrogen bonds form chains of molecules parallel to [100]
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