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461.
Existence and Uniqueness of Solutions for Time-Fractional Oldroyd-B Fluid Equations with Generalized Fractional Derivatives
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Hassan Messaoudi Abdelouaheb Ardjouni Salah Zitouni 《Journal of Nonlinear Modeling and Analysis》2024,6(1):142-151
In this paper, we study the existence and uniqueness of solutions for time-fractional Oldroyd-B fluid equations with generalized fractional derivatives. We distinguish two cases. Firstly for the linear case, we get regularity results under some hypotheses of the source function and the initial data. Secondly for the nonlinear case, we use the Banach fixed point theorem to obtain the existence and uniqueness of solutions. 相似文献
462.
Composite polymer membranes of poly(vinyl alcohol) (PVA) and iron oxide (Fe3O4) nanoparticles were produced in this work. X-ray diffraction measurements demonstrated the formation of Fe3O4 nanoparticles of cubic structures. The nanoparticles were synthesized by a coprecipitation technique and added to PVA solutions with different concentrations. The solutions were then used to generate flexible membranes by a solution casting method. The size and shape of the nanoparticles were investigated using scanning electron microscopy (SEM). The average size of the nanoparticles was nm. Raman spectroscopy and Fourier-transform infrared spectroscopy (FTIR) were utilized to investigate the structure of the membranes, as well as their vibration modes. Thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) demonstrated the thermal stability of the membranes and the crystallinity degree. Electrical characteristics of the thin membranes were examined using impedance spectroscopy as a function of the nanoparticles’ concentrations and temperatures. The resistivity of the fabricated flexible membranes was possible to adjust by controlled doping with suitable concentrations of nanoparticles. The activation energy decreased with the nanoparticles’ concentrations due to the increase in charge carriers’ concentrations. Therefore, the fabricated membranes may be applied for practical applications that involve the recycling of nanoparticles for multiple application cycles. 相似文献
463.
Marwa Ibrahim Helmy Samah Sabry Saad Maha Abdelmonem Hegazy Ahmed Salah Fayed 《Journal of separation science》2022,45(10):1646-1655
Tolperisone and etodolac were proven to have synergistic effect for patients of acute low back pain associated with musculoskeletal spasm. In this work, a specific, highly sensitive and reproducible analytical method was developed and validated for the simultaneous determination of tolperisone and etodolac in human plasma using liquid chromatography-tandem mass spectrometric technique. Liquid–liquid extraction was optimized for sample preparation. Zorbax C8 column (3.5 μm, 50 × 4.6 mm) was used, carrying a mobile phase mixture of 10.0 mM ammonium formate:acetonitrile (40:60, v/v) pH 3.8, running in an isocratic mode. Chlorzoxazone acted as an internal standard. Sample volume of injection was 5.0 μL, and analysis was achieved within 2.5 min. Detection and quantitation were performed by electrospray ionization mass spectrometry using the multiple-reaction monitoring mode. The proposed method could determine the analytes in the range of concentration 0.5–200.0 ng mL−1 for tolperisone and 0.05–20.0 μg mL−1 for etodolac. Findings of inter- and intraday precisions were ≤12.3% with accuracy of ±5.0%. Pharmacokinetics study for the two drugs after oral administration of healthy human volunteers was achieved with the aid of application of the developed study. 相似文献
464.
Stilbene and 2-arylbenzofuran glucosides from the rhizomes of Schoenocaulon officinale 总被引:3,自引:0,他引:3
Kanchanapoom T Suga K Kasai R Yamasaki K Kamel MS Mohamed MH 《Chemical & pharmaceutical bulletin》2002,50(6):863-865
Two stilbene glucosides, oxyresveratrol 2-O-beta-glucopyranoside and resveratrol 3,4'-O,O'-di-beta-D-glucopyranoside, and a 2-arylbenzofuran glucoside, schoenoside, were isolated from the rhizomes of Schoenocaulon officinale, along with five known compounds, oxyresveratrol 3'-O-beta-D-glucopyranoside, oxyresveratrol, resveratrol 3-O-beta-D-glucopyranoside, mulberroside A and moracin M 3'-O-beta-D-glucopyranoside. The structural elucidations were based on analyses of both physical and spectroscopic data. 相似文献
465.
This work presents a finite element solution of the 3D magneto‐hydrodynamics equations. The formulation takes explicitly into account the local conservation of the magnetic field, giving rise to a conservative formulation and introducing a new scalar variable. A stabilization technique is used in order to allow equal linear interpolation on tetrahedral elements of all the variables. Numerical tests are performed in order to assess the stability and the accuracy of the resulting methods. The convergence rates are calculated for different stabilization parameters. Well‐known MHD benchmark tests are calculated. Results show good agreement with analytical solutions. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
466.
Adsorption of strontium (II) ions from aqueous solution onto bottom ash of expired drug incineration
Brahimi Abdelkarim Mellah Abdelhamid Hanini Salah 《Journal of Radioanalytical and Nuclear Chemistry》2021,330(3):929-940
Journal of Radioanalytical and Nuclear Chemistry - Bottom Ash of Expired Drug Incineration (BAEDI) is used in this study for the removal of Sr(II). In the kinetic study, the experimental results... 相似文献
467.
In this paper, we consider a coupled Lamé system of nonlinear viscoelastic equations with general source terms. Under some suitable conditions on the initial data and the relaxation functions, we prove an asymptotic stability result of global solution taking into account that the kernel is not necessarily decreasing. This work generalizes and improves earlier results in the literature. 相似文献
468.
Ahmed Jawad Shahzad Azeem Farooq Aamir Kamran Muhammad Ud-Din Khan Salah Ud-Din Khan Shahab 《Journal of Thermal Analysis and Calorimetry》2021,144(6):2175-2185
Journal of Thermal Analysis and Calorimetry - The purpose of this study is to examine the flow features and heat transfer in the presence of nanoparticles which are used to enhance the... 相似文献
469.
Fatma Bassyouni Mohammad Tarek Abeer Salama Bassant Ibrahim Sawsan Salah El Dine Nemat Yassin Amina Hassanein Maysa Moharam Mohamed Abdel-Rehim 《Molecules (Basel, Switzerland)》2021,26(8)
Diabetes is the most common metabolic disorder in both developing and non-developing countries, and a well-recognized global health problem. The WHO anticipates an increase in cases from 171 million in 2000 to 366 million by 2030. In the present study, we focus on the preparation of pyrimidine derivatives as potential antidiabetic and antimicrobial agents. Thein vivoeffect on total serum glucose concentration, cholesterol and antioxidant activity was assessed in adult male albino Wister rats and compared to the reference drug glimperide. Promising results were observed for compound 5. The histopathological study confirms that compound 5 results in significant activity with liver maintenance. The antimicrobial activities were evaluated against several bacterial strains such as Salmonella typhimurium ATCC 25566, Bacillus cereus, Escherichia coli NRRN 3008, Pseudomonas aeruginosa ATCC 10145, Staphylococcus aureus ATCC 6538and fungi such as Rhizopus oligosporus, Mucor miehei and Asperillus niger. Compounds 4 and 5 showed a good inhibition of the bacterial zone compared to the reference drug cephradine. Finally, we suggest protein targets for these drugs based on computational analysis, and infer their activities from their predicted modes of binding using molecular modeling. The molecular modeling for compounds 4 and 5 resulted in improved docking scores and hydrogen bonding. The docking studies are in good agreement with the in vitro and in vivo studies. 相似文献
470.