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991.
Mustafa Erol 《Czechoslovak Journal of Physics》2000,50(5):665-670
We report electrical transport properties of intentionally and unintentionally doped wurtzite GaN epilayers within the temperature range of 3K up to 340 K. Specifically, temperature dependence of the carrier concentration, mobility and resistivity are investigated. Obtained data could only be explained on the basis of two-band model, namely, high mobility conduction band and low mobility impurity band. The threshold doping concentration for the dominance of the conduction band electrons is estimated to be about 1018 cm–3. 相似文献
992.
Islam Mohammad Rakibul Iftekher A. N. M. Hasan Kazi Rakibul Nayen Md. Julkar Islam Saimon Bin Hossain Aadreeta Mustafa Zareen Tahsin Tahia 《Optical and Quantum Electronics》2021,53(2):1-17
Optical and Quantum Electronics - Optical sensors are very attractive in chemical and bio-chemical applications due to some unique characteristics, such as immunity to electromagnetic interference... 相似文献
993.
In this paper, two integrating strategies namely exp[-Φ(X)] and G'/G~2-expansion methods together with the attributes of local-M derivatives have been acknowledged on the electrical microtubule(MT) model to retrieve soliton solutions. The said model performs a significant role in illustrating the waves propagation in nonlinear systems. MTs are also highly productive in signaling, cell motility, and intracellular transport. The proposed algorithms yielded solutions of bright, dark, singular, and combo fractional soliton type. The significance of the fractional parameters of the fetched results is explained and presented vividly. 相似文献
994.
Abdullah KEPCEOLU Yasemin GÜNDODU Adem SARILMAZ Mustafa ERS
Z Faruk
ZEL Hamdi ükür KILI 《Turkish Journal of Chemistry》2021,45(2):485
In this study, rhenium/rhenium oxide nanoparticles (Re / ReO3 NPs) have been produced for the first time in ultrapure water by using Femtosecond Pulsed Laser Ablation in Liquid (fsPLAL) method. X-Ray Diffraction (XRD) measurements and results obtained for NPs show the existence of well-crystallized peaks and preferred phases. Re NPs have hexagonal structure while ReO3 NPs have the perovskite-like cubic crystal structures. The Re / ReO3 ratio is also determined to be 53 / 47 with ~ 20 nm crystallite size, while pure ReO3 crystallite sizes were measured to be ~ 25 nm. The TEM results have shown that the produced particles have a spherical shape, and particle sizes changes between ~ 20 nm and ~ 60 nm. The crystallite size is similar due to XRD results. Obtained nanoparticles exhibit promising applications for photonic devices with broad bandgap values which have measured to be 4.71 eV for Re / ReO3 NPs mixture and 4.36 eV for pure ReO3 NPs. 相似文献
995.
Yu-Ming Chu Muhammad Farooq Khan Saif Ullah Syed Azhar Ali Shah Muhammad Farooq Mustafa bin Mamat 《Mathematical Methods in the Applied Sciences》2023,46(1):232-247
Vector–host diseases outbreak is a major public health concern, and it has greatly affected human health and economy in various regions around the globe. Different approaches have been adopted to investigate the dynamical behavior and possible control of these diseases. In this study, we present a compartmental transmission model in order to explore the dynamics of vector–host infectious diseases. The saturated incidence rate instead of bilinear (or standard) and saturated treatment function is considered in model formulation which enhance the biological suitability of the proposed model. We first formulate the model based on nonlinear classical integer-order differential equations. Then, the proposed integer-order model is reformulated using the fractional-order operator in Caputo–Fabrizio sense with nonsingular kernel. We investigate the model equilibria and evaluate the expression for the most important threshold parameter known as the basic reproduction number. Furthermore, the existence and uniqueness are presented via the fixed point approach. Additionally, using an efficient numerical scheme, the iterative solution of the model is obtained. Finally, we present the model simulations to illustrate the impact of arbitrary fractional order and some of other important parameters involved in the model on the disease dynamics and minimization. 相似文献
996.
Synthesis of 3,5‐Diarylcyclohex‐2‐enones by NH4Cl/HCl‐Catalyzed Cyclization and Deacetylation of 4‐Acetylhexane‐1,5‐diones
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A new route for the synthesis of 3,5‐diarylcyclohex‐2‐enones is reported. The 4‐acetyl‐1,3‐diarylhexane‐1,5‐diones were obtained by the addition of pentane‐2,4‐dione to chalcones. The reaction of 4‐acetyl‐1,3‐diarylhexane‐1,5‐diones with NH4Cl/HCl in EtOH under reflux conditions gave the 3,5‐diarylcyclohex‐2‐enones in good yields. All synthesized compounds were characterized by spectroscopic methods (1H‐, 13C‐NMR, and IR), and elemental analyses. 相似文献
997.
Synthesis of chalcone‐containing methacrylate‐based hydrogen bonded side chain liquid crystalline polymer and its dielectric properties
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Burak Korkmaz Yesim Hepuzer Gursel Nimet Yilmaz Canli Zeynep Güven Özdemir Mustafa Okutan Bahire Filiz Senkal 《先进技术聚合物》2017,28(11):1351-1356
In this work, a new methacrylate‐based hydrogen bonded side chain liquid crystalline polymer having chalcone moieties (HBCP) was prepared from poly(4‐(3‐(pyridin‐4‐yl)acryloyl) phenyl methacrylate) and 11‐(4‐cyanobiphenyl‐4(‐oxy) undekan‐1‐ol (LC11)) by molecular self‐assembly processes via hydrogen bond formation between nitrogen of the HBCP and hydroxyl group of the LC11. The formation of H bond was confirmed by using Fourier transform infrared (FTIR) spectroscopy. The phase transition temperatures and liquid crystalline phases of the HBCP were examined by DSC and POM measurements. The dielectric properties of HBCP have been determined by impedance analyzer within the frequency interval of 100 Hz–15 MHz. According to Cole–Cole plot, the equivalent circuit of the LC system has been found as a capacitor in parallel with a resistor. The resonance frequency, fr, of the R–C circuit has also been calculated as 1.59 MHz by phase angle versus frequency curve. The dielectric relaxation type of HBCP has been determined as nearly‐Debye type because the absorption coefficient, α, equals to 0.01655. From the conductivity point of view, HBCP displays dc conductivity at the low and high frequency regions that correspond to 100 Hz–12 kHz and 3.3 MHz–15 MHz, respectively. On the other hand, it has been revealed that the ac conductivity of the LC system investigated obeys Super Linear Power Law (SLPL) at the intermediate frequency domain. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
998.
A high accuracy minimally invasive regularization technique for navier–stokes equations at high reynolds number
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Mustafa Aggul Alexander Labovsky 《Numerical Methods for Partial Differential Equations》2017,33(3):814-839
A method is presented, that combines the defect and deferred correction approaches to approximate solutions of Navier–Stokes equations at high Reynolds number. The method is of high accuracy in both space and time, and it allows for the usage of legacy codes a frequent requirement in the simulation of turbulent flows in complex geometries. The two‐step method is considered here; to obtain a regularization that is second order accurate in space and time, the method computes a low‐order accurate, stable, and computationally inexpensive approximation (Backward Euler with artificial viscosity) twice. The results are readily extendable to the higher order accuracy cases by adding more correction steps. Both the theoretical results and the numerical tests provided demonstrate that the computed solution is stable and the accuracy in both space and time is improved after the correction step. We also perform a qualitative test to demonstrate that the method is capable of capturing qualitative features of a turbulent flow, even on a very coarse mesh. © 2016 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 33: 814–839, 2017 相似文献
999.
Muhammad I. Mustafa Mohammad Kafini 《Mathematical Methods in the Applied Sciences》2017,40(4):883-895
In this paper, we consider a plate equation with infinite memory in the presence of delay and source term. Under suitable conditions on the delay and source term, we establish an explicit and general decay rate result without imposing restrictive assumptions on the behavior of the relaxation function at infinity. Our result allows a wider class of relaxation functions and improves earlier results in the literature. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
1000.
We proved the noncommutative analogue of Calderón’s result for fully symmetric spaces \(E_1\) and \(E_2\) on (0, 1) and for a finite von Neumann algebra \({{\mathcal {M}}}\). We also proved the noncommutative symmetric Hardy space’s analogue of Calderón’s result for fully symmetric spaces and for finite subdiagonal subalgebras. 相似文献