617 research outputs found

    Enhancing the rheological properties and shale inhibition behavior of water-based mud using nanosilica, multi-walled carbon nanotube, and graphene nanoplatelet

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    Five different drilling mud systems namely potassium chloride (KCl) as a basic mud, KCl/partial hydrolytic polyacrylamide (PHPA), KCl/graphene nanoplatelet (GNP), KCl/nanosilica and KCl/multi-walled carbon nano tube (MWCNT) were prepared and investigated for enhancement of rheological properties and shale inhibition. Nanoparticles were characterized in drilling mud using transmission electron microscope (TEM) analysis. Mineralogical analysis of shale was examined by X-ray diffraction (XRD). Five shale plugs were prepared using compactor cell for the determination of shale swelling. Shale swelling was determined using the linear swell meter (LSM) for 20 hours. Results revealed that basic mud and KCl/polymer mud systems shows 30% and 24% change in shale volume. MWCNT, nanosilica and GNP were added separately in the KCl mud system. 0.1 ppb of each MWCNT and nanosilica showed 32% and 33% change in shale volume. However, when the shale was interacted with WBM containing 0.1 ppb of GNP, it was found that only 10% change in shale volume occurred. The results showed that the addition of nanoparticles in the KCl mud system improved the shale inhibition. API, HPHT filtrate loss volume, plastic viscosity (PV) and yield point (YP) were improved using GNP. It is learned from the experimental work that small concentration of KCl with GNP can mitigate shale swelling compared to the mud contains higher concentration of KCl and PHPA in WBM. Thus, GNP can be a better choice for enhancement of WBM performance

    Hemoglobin E B-Thalassemia in a Pakistani Family

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    Hemoglobin E is a slow moving B chain variant of hemoglobin, first discovered by Itano1. Characterized by Hunt et al2 showed glutamic acid at B 26 to be replaced by lysine. It is a common variant of hemoglobin in the world and reported in high frequency from South-East Asia3-6. Cases of Hb E, in combination with thalassemia have been reported on the basis of electrophoretic pattern only. In this communication a case of Hb E with B thalassemia is reported on the basis of amino acid sequencing of the abnormal peptide

    Attitudes of Islamic Learning and Education Faculty Students Towards English Language at Karachi University

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    The research paper aims at studying the attitudes of the students of Islamic Learning and Education Faculty towards English at the University of Karachi. It is based on testing the hypothesis that the students of Islamic Learning Faculty have less positive attitudes towards English as compared to the students of Education faculty through a survey on first year students of both faculties. A five-point Likert scale was used to conduct a survey on 151 students of the Islamic Learning faculty and 135 students of the Education faculty. The results were calculated using an independent t-testand standard deviation which reveals that there is a minor difference in the attitudes of thestudent of both faculties. The students of the Education faculty showed more positive attitudes when asked about the importance of English as compared to the attitudes of the students of Islamic Learning Faculty. However, the difference in their attitude is negligible. As the results reveal a minor association between the attitudes of the learners and their faculty, the study; therefore, proves the null hypothesiswhich says that there is no significant difference between the attitudes of the students of both the faculties. Keywords: attitudes; English language; t-test; standard deviation; Islamic learning faculty; education faculty; likert-scale

    Structural Properties and Relative Stability of (Meta)Stable Ordered, Partially-ordered and Disordered Al-Li Alloy Phases

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    We resolve issues that have plagued reliable prediction of relative phase stability for solid-solutions and compounds. Due to its commercially important phase diagram, we showcase Al-Li system because historically density-functional theory (DFT) results show large scatter and limited success in predicting the structural properties and stability of solid-solutions relative to ordered compounds. Using recent advances in an optimal basis-set representation of the topology of electronic charge density (and, hence, atomic size), we present DFT results that agree reasonably well with all known experimental data for the structural properties and formation energies of ordered, off-stoichiometric partially-ordered and disordered alloys, opening the way for reliable study in complex alloys.Comment: 7 pages, 2 figures, 2 Table

    Modification of cellulose ether with organic carbonate for enhanced thermal and rheological properties: Characterization and analysis

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    Reduction in viscosity at higher temperatures is the main limitation of utilizing cellulose ethers in high thermal reservoir conditions for petroleum industry applications. In this study, cellulose ether (hydroxyethyl methyl cellulose (HEMC)) is modified using organic carbonates, i.e., propylene carbonate (PC) and diethyl carbonate (DEC), to overcome the limitation of reduced viscosity at high temperatures. The polymer composites were characterized through various analytical techniques, including Fourier-transform infrared (FTIR), H-NMR, X-ray diffraction (XRD), scanning electron microscope (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), -potential measurement, molecular weight determination, and rheology measurements. The experimental results of structural and morphological characterization confirm the modification and formation of a new organic carbonate-based cellulose ether. The thermal analysis revealed that the modified composites have greater stability, as the modified samples demonstrated higher vaporization and decomposition temperatures. -potential measurement indicates higher stability of DEC- and PC-modified composites. The relative viscometry measurement revealed that the modification increased the molecular weight of PC- and DEC-containing polymers, up to 93,000 and 99,000 g/moL, respectively. Moreover, the modified composites exhibited higher levels of stability, shear strength and thermal resistance as confirmed by viscosity measurement through rheology determination. The observed increase in viscosity is likely due to the enhanced inter- and intramolecular interaction and higher molecular weight of modified composites. The organic carbonate performed as a transesterification agent that improves the overall properties of cellulose ether (HEMC) at elevated temperatures as concluded from this study. The modification approach in this study will open the doors to new applications and will be beneficial for substantial development in the petroleum industry

    Population characteristics of Brueelia sp. on certain Indian Finches

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    Five kinds of finches were examined during 2004-06. Two kinds of finches were found infested with ischnoceran lice, Brueelia sp. (Prevalence-20.5%, mean intensity of infestation-4.7 and range of infestation, 1-23). The frequency distribution pattern of Brueelia sp. on Indian finches conformed to the negative binomial model. Sex ratio was skewed in favour of females and adults outnumbered the nymphs in natural population

    Prenatal Diagnosis of Maternal Serum from Mothers Carrying β-thalassemic Fetus

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    Background Current study focused on discovering protein biomarkers from the maternal serum of β-thalassemic trait mothers carrying the normal fetus and β-thalassemic major fetus. Method Serum samples from β-thalassemic trait mothers carrying major (N=5) and normal fetuses (N=5) were studied. IVS1-5 thalassemia mutation was common among β-thalassemic trait mothers who were carrying homozygous β-thalassemic fetus (IVS1-5/ IVS1-5 mutation) or normal fetus (no mutation). We employed two-dimensional gel electrophoresis and mass spectrometric analysis to explore differentially expressed maternal serum proteins from thalassemia carrier couples having the same β-thalassemia mutation. Western blotting was performed for one of the identified proteins to validate our data. Results Ten proteins were identified in maternal serum of β-thalassemic trait mothers carrying the β-thalassemic major fetus and normal fetus. Among these, Serotransferrin, Haptoglobin, Alpha-1 anti-trypsin (A1AT), Apo-lipoprotein A1, and Fibrinogen-beta chain were found to be up-regulated in mothers carrying major fetuses and are known to be associated with pregnancy-related disorders. The expression of A1AT was validated through western blotting. Conclusion Proteins identified in the current study from maternal serum are reported to contribute to hereditary disorders. We suggest that these can serve as putative screening markers for non-invasive prenatal diagnosis in β-thalassemic pregnancies

    SERCA2 Regulates Non-CF and CF Airway Epithelial Cell Response to Ozone

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    Calcium mobilization can regulate a wide range of essential functions of respiratory epithelium, including ion transport, ciliary beat frequency, and secretion of mucus, all of which are modified in cystic fibrosis (CF). SERCA2, an important controller of calcium signaling, is deficient in CF epithelium. We conducted this study to determine whether SERCA2 deficiency can modulate airway epithelial responses to environmental oxidants such as ozone. This could contribute to the pathogenesis of pulmonary exacerbations, which are important and frequent clinical events in CF. To address this, we used air-liquid interface (ALI) cultures of non-CF and CF cell lines, as well as differentiated cultures of cells derived from non-CF and CF patients. We found that ozone exposure caused enhanced membrane damage, mitochondrial dysfunction and apoptotic cell death in CF airway epithelial cell lines relative to non-CF. Ozone exposure caused increased proinflammatory cytokine production in CF airway epithelial cell lines. Elevated proinflammatory cytokine production also was observed in shRNA-mediated SERCA2 knockdown cells. Overexpression of SERCA2 reversed ozone-induced proinflammatory cytokine production. Ozone-induced proinflammatory cytokine production was NF-κB- dependent. In a stable NF-κB reporter cell line, SERCA2 inhibition and knockdown both upregulated cytomix-induced NF-κB activity, indicating importance of SERCA2 in modulating NF-κB activity. In this system, increased NF-κB activity was also accompanied by increased IL-8 production. Ozone also induced NF-κB activity and IL-8 release, an effect that was greater in SERCA2-silenced NF-κB-reporter cells. SERCA2 overexpression reversed cytomix-induced increased IL-8 release and total nuclear p65 in CFTR-deficient (16HBE-AS) cells. These studies suggest that SERCA2 is an important regulator of the proinflammatory response of airway epithelial cells and could be a potential therapeutic target
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