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This paper presents the oil uptake of porous sorbent polymer sheets consisting of ultra‐high molecular weight polyethylene. A comprehensive set of experiments are performed showing the saturation contact time, retention value, mechanical properties, oil pick‐up ratio, pick‐up density, and dynamic dripping profile. Kinetic modeling of the oil sorption is also provided. The experimental results show a good correlation with the pseudo‐second order model. The sheets exhibit high oil uptake speeds, requiring less than 2 min in contact with the oil to reach saturation. The sheets fulfill the criteria of high uptake kinetics, high sorption capacity, and high mechanical strength simultaneously. Those characteristics enable their use in practical spill response. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Qazi SJ Rennie AR Wright JP Cockcroft JK 《Langmuir : the ACS journal of surfaces and colloids》2010,26(24):18701-18709
High-energy angle-dispersive X-ray diffraction has been used to study the alignment of colloidal suspension of kaolinite particles in water as they flow along a pipe. X-rays with energies above 25 keV have a major advantage, as they can penetrate through thick samples and walls of containers and permit investigation of samples under realistic flow conditions. As an example of the method, flow through a circular cross-section pipe with an internal diameter of 5 mm has been studied: this is typical of industrial applications. The angular distribution of intensities of peaks in the diffraction pattern as a function of the location of the pipe in the X-ray beam provides information about the alignment of particles under flow. Order parameters have been calculated to describe the alignment and direction of orientation. It is observed that the particles align in the direction of flow with their flat faces parallel to the flow. The experimental results are compared with the calculations of the local strain rate that help to explain the onset of alignment of the particles. 相似文献
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Physical and chemical analysis of the polysaccharide isolated from Sargassum Terarrium (brown algae) of Karachi coast showed characteristics of the sodium alginate. Optical rotations and sulphated ash content were found and FTIR spectra showed a sharp and strong absorption band at 1600 cm?1 representing carboxylate ion which conforms high uronic acid content of the product. The viscosities of aqueous 0.1% sodium alginate solution were measured in the presence of copper II chloride (CuCl2). The viscosities were found to be increased with the increase in the concentration of electrolyte. Viscosities were also found affected with temperature. ‘A’ and ‘B’ coefficients of Jones–Dole equation were evaluated. The increase in positive values of ‘B’ coefficient with the rise of temperature led to conclusion that given electrolyte in 0.1% aqueous sodium alginate solution behaves as structure maker. Thermodynamic parameters regarding to activated state like energy of activation Eη, change in free energy of activation ΔGη and change of entropy of activation ΔSη were also evaluated. Straight-line plots of log η versus 1/T observed with positive slopes show the effect of temperature on the viscosities of solutions. Energy of activation (Eη) was found to be decreased with the rise of temperature. Change in free energy of activation (ΔGη) was also found to be increased with increase in concentrations of electrolyte and also with rise of temperature. The values of change in entropy of activation (ΔSη) were also calculated. Negative values of ΔSη were found to be increased with increase in concentration of electrolyte and also with rise of temperature. 相似文献
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Junaid Aslam Sheba Haque Khan Saeed Ahmad Khan 《Journal of Saudi Chemical Society》2012,16(2):125-129
In present communication, effect of in vitro and ex vitro culture conditions was investigated on the yield of fat soluble vitamins in chickpea (Cicer arietinum L.) seedlings analyzed by high performance liquid chromatography (HPLC). Amongst the tested culture conditions (in vitro and ex vitro); in vitro condition proved to be highly effective compared to ex vitro. We noticed a significant difference in vitamins D (ergocalciferol), E (α-tocopherol) and K (phylloquinone) yields in chickpea seedlings grown in two different conditions. Maximum yield with a linear increase in vitamins D and E was noticed upto 9 days old in vitro grown seedlings. Vitamin K yield was also high in in vitro grown seedlings with a linear increase upto 11 days. Although, vitamin A was not detected, the vitamin production in germinating seeds was, therefore, age and culture condition dependent. The study revealed that, in in vitro condition, the level of fat soluble vitamins enhanced in seedlings, which could be used for human consumption with value addition in the diet of vegetarians. 相似文献
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Syed Nasir Abbas Bukhari Hasan Ejaz Mervat A. Elsherif Kashaf Junaid Islam Zaki Reham E. Masoud 《Molecules (Basel, Switzerland)》2022,27(8)
New furan-based derivatives have been, designed, synthesized, and evaluated for their cytotoxic and tubulin polymerization inhibitory activities. DNA flow cytometric study of pyridine carbohydrazide 4 and N-phenyl triazinone 7 demonstrated G2/M phase cell cycle disruptions. Accumulation of cells in the pre-G1 phase and positive annexin V/PI staining, which may be caused by degeneration or fragmentation of the genetic components, suggested that cell death occurs via an apoptotic cascade. Furthermore, compounds 4 and 7 had a strong pro-apoptotic impact through inducing the intrinsic mitochondrial mechanism of apoptosis. This mechanistic route was verified by an ELISA experiment that indicated a considerable rise in the levels of p53 and Bax and a drop in the level of Bcl-2 when compared with the control. 相似文献
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Perpetua Wanjiru Muchiri M. Agouri Sahar Abdeen Mohamed A. Abbassi S. Taj B. Manaut Ashim Dutta Junaid Khan T. Mundad Youssef Bakkour Murefah mana Al-Anazy 《International journal of quantum chemistry》2024,124(7):e27368
This research work investigates the structural, electronic, optical, and thermoelectric characteristics of VFeZ (Z = N and P) half-Heusler compounds. The study employs the full-potential linearized augmented plane wave (FP-LAPW) method integrated into the WIEN2K algorithm, serving as the underpinning framework for density functional theory (DFT) analysis. In the study, we use the PBE generalized gradient approximation (PBE-GGA) to identify numerous parameters associated with structural and elastic properties. Lattice parameter results are in agreement with previous outcomes. Moreover, computed elastic parameters satisfy the criterion for stability. In the cubic structure VFeZ (Z = N and P) is ductile, to enhance the computations of electronic characteristics, Tran and Blaha's modified Becke-Johnson potential (TB-mBJ) is used. Our simulations demonstrate that the materials exhibit semiconductor behavior, with a direct band gap for VFeZ (Z = N and P). Strong UV absorption is found via optical experiments suggest compounds are suitable for optical application. Furthermore, study of the thermoelectric properties suggests its application in the thermoelectric generators. 相似文献
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Various in vitro grown tissues (non-regenerative callus, regenerative callus and microshoot derived leaves) of Solanum nigrum L. were cultured under salinity stress (0-150 mM NaCl) for enhanced production of solasodine, a steroidal alkaloid and an alternative to diosgenin, which is used as a precursor for the commercial production of steroidal drugs. The role of plant growth regulators and various concentrations of NaCl during in vitro production of solasodine was studied. The in vitro yield was compared with the yield from leaves of field grown plant. Solasodine content was maximum (2.39 mg/g dry wt.) in regenerative callus when grown on medium added with 150 mM NaCl; followed by in vitro raised leaf of microshoot. Quantitative estimation of solasodine was carried out using a new HPTLC method, which is validated for its recovery and precession. The proposed HPTLC method showed a good linear relationship (r(2)=0.994) in 50-2000 ng/spot concentration ranges. The data demonstrate that the solasodine production in cultures was growth dependent. 相似文献
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Masood Yousaf M W Younis Ahmed S Jbara M Junaid Iqbal Khan G Murtaza M A Saeed 《理论物理通讯》2022,74(3):35701
Methods capable of tuning the properties of van der Waals (vdW) layered materials in a controlled and reversible manner are highly desirable. Interfacial electronic properties of two-dimensional vdW heterostructure consisting of silicene and indium selenide (InSe) have been calculated using density functional theory-based computational code. Furthermore, in order to vary the aforementioned properties, silicene is slid over a InSe layer in the presence of Li intercalation. On intercalation of the heterostructure, the buckling parameter associated with the corrugation of silicene decreases from 0.44 Å to 0.36 Å, whereas the InSe structure remains unaffected. Potential energy scans reveal a significant increase in the sliding energy barrier for the case of intercalated heterostructure as compared with the unintercalated heterostructure. The sliding of the silicene encounters the maximum energy barrier of 0.14 eV. Anisotropic analysis shows the noteworthy differences between calculated in-plane and out-of-plane part of dielectric function. A variation of the planar average charge density difference, dipole charge transfer and dipole moment have been discussed to elucidate the usability spectrum of the heterostructure. The employed approach based on intercalation and layer sliding can be effectively utilized for obtaining next-generation multifunctional devices. 相似文献