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31.
Noreen Sher Akbar 《Applicable analysis》2013,92(7):1420-1438
This paper describes the Peristaltic flow of a Jeffrey-six constant fluid in an endoscope. The two-dimensional equation of Jeffrey-six constant fluid is simplified by making the assumptions of long wave length and low Reynolds number. The reduced momentum equations are solved with three methods, namely (i) Perturbation method, (ii) Homotopy analysis method, and (iii) shooting method. The comparison of the three solutions shows a very good agreement between the three results. The expressions for pressure rise and frictional forces per wave length have been also computed numerically. Finally, the pressure rise, frictional forces are plotted for different parameters of interest. 相似文献
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Noreen Rehmat Ivan V. Kurganskii Dr. Zafar Mahmood Qing Lin Guan Prof. Jianzhang Zhao Prof. Yong Heng Xing Prof. Gagik G. Gurzadyan Prof. Matvey V. Fedin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(17):5521-5535
Perylenebisimide ( PBI )–anthracene ( AN ) donor–acceptor dyads/triad were prepared to investigate spin–orbit charge-transfer intersystem crossing (SOCT-ISC). Molecular conformation was controlled by connecting PBI units to the 2- or 9-position of the AN moiety. Steady-state, time-resolved transient absorption and emission spectroscopy revealed that chromophore orientation, electronic coupling, and dihedral angle between donor and acceptor exert a significant effect on the photophysical property. The dyad PBI-9-AN with orthogonal geometry shows weak ground-state coupling and efficient intersystem crossing (ISC, ΦΔ=86 %) as compared with PBI-2-AN (ΦΔ=57 %), which has a more coplanar geometry. By nanosecond transient absorption spectroscopy, a long-lived PBI localized triplet state was observed (τT=139 μs). Time-resolved EPR spectroscopy demonstrated that the electron spin polarization pattern of the triplet state is sensitive to the geometry and number of AN units attached to PBI . Reversible and stepwise generation of near-IR-absorbing PBI radical anion ( PBI−⋅ ) and dianion ( PBI2− ) was observed on photoexcitation in the presence of triethanolamine, and it was confirmed that selective photoexcitation at the near-IR absorption bands of PBI.− is unable to produce PBI2− . 相似文献
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Ahmad Mohammad Nazir Mahmood Ahmad Kamil Hashim Kamarul Faizal Mustakim Fajaruddin Bin Selamat Ali Bajuri Mohd Yazid Arshad Noreen Izza 《Journal of Thermal Analysis and Calorimetry》2021,145(4):2209-2224
Journal of Thermal Analysis and Calorimetry - Graphene oxide/silica composite’s rheological behavior was studied in this investigation. This composite was made to reduce the cost of... 相似文献
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Akhtar R. Noreen R. Raza Z. Rasul A. Zahoor A. F. 《Russian Journal of Organic Chemistry》2022,58(4):541-548
Russian Journal of Organic Chemistry - Fluoroquinolones constitute a well-known class of antibacterial agents that also display significant anticancer activity. In recent years, various... 相似文献
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Non-Newtonian fluid model for blood flow through a tapered artery with a stenosis and variable viscosity by modeling blood as Jeffrey fluid has been studied in this paper.The Jeffrey fluid has two parameters,the relaxation time λ1 and retardation time λ2.The governing equations are simplified using the case of mild stenosis.Perturbation method is used to solve the resulting equations.The effects of non-Newtonian nature of blood on velocity profile,temperature profile,wall shear stress,shearing stress at the stenotsis throat and impedance of the artery are discussed.The results for Newtonian fluid are obtained as special case from this model. 相似文献
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In the present investigation we have studied the peristaltic flow of a nanofluid in an endoscope. The flow is investigated in a wave frame of reference moving with velocity of the wavec. Analytical solutions have been calculated using Homotopy perturbation method (HPM) for temperature and nanoparticle equation while exact solutions have been calculated for velocity and pressure gradient. Numerical integration have been used to obtain the graphical results for pressure rise and frictional forces. The effects of various emerging parameters are investigated for five different peristaltic waves.
Streamlines have been plotted at the end of the article. 相似文献
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S. Nadeem Noreen Sher Akbar M.Y. Malik 《Numerical Methods for Partial Differential Equations》2010,26(6):1660-1674
In this article, we have analyzed the effects of heat transfer on a peristaltic flow of a micropolar fluid in a vertical annulus. The governing equations of two‐dimensional micropolar fluid are simplified by using the assumptions of long wavelength and neglecting the wave number. A close form solutions are obtained for velocity field υx and microrotation component υθ. Further, the numerical solutions of the simplified equation of υθ are computed and the results are compared with the exact solution. The influence of pertinent parameters are analyzed through graphs. Trapping phenomena is also discussed for different parameters. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2010 相似文献
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Agger JR Hanif N Anderson MW 《Angewandte Chemie (International ed. in English)》2001,40(21):4065-4067
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Kiran Aftab Kalsoom Akhtar Razia Noreen Faiza Nazir Umme Kalsoom 《Chemistry Central journal》2017,11(1):133
The present investigation aimed to study and compare the efficiency of non-viable fungal isolates to remove divalent lead (Pb(II)) from aqueous streams. The selected fungal isolates showed identity with Aspergillus caespitosus, Aureobasidium sp. RBSS-303 and Aspergillus flavus HF5 as confirmed using gene sequencing of ITS regions of the ribosomal DNA (rDNA). The obtained equilibrium data for Pb(II) biosorption of A. caespitosus fitted better to Langmuir isotherm with maximum sorption capacity of 351.0 mg/g and A. sp. RBSS-303 and A. flavus HF5 showed good fit to Freundlich isotherm with maximum sorption capacity of 271.5 and 346.3 mg/g respectively. The values of thermodynamic factors ascertained the nature of adsorption process is endothermic with A. caespitosus and A. flavus HF5 but exothermic with A. sp. RBSS-303. The experimental data for Pb(II) biosorption fits very well to pseudo second order kinetic model. With HCl the maximum 85.5, 75.3, 73.7% recovery of Pb(II) was obtained from A. caespitosus, A. sp. RBSS-303 and A. flavus HF5, respectively. The observed percentage loss in sorption capacity of Pb(II) was 3.9% by A. flavus HF5, 12.2% by A. caespitosus and 26.6% by A. sp. RBSS-303 after five cyclic studies of sorption and desorption. Results from the study confirmed the efficiency order of A. caespitosus > A. flavus HF5 > A. sp. RBSS-303 to remove and recover Pb(II) from aqueous solution. Finally, the fungal biosorbents can be used as soil conditioning agent after compositing into valuables fungal protein. 相似文献