Büşra Uzun;Mustafa Özgür Yaylı;Ömer Civalek; 《ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik》2024,104(7):e202301093

In this work, an attention is paid to the prediction of torsional vibration frequencies of functionally graded porous nanotubes based on the Lam strain gradient elasticity theory. The nanotubes are formed of functionally graded porous nanomaterials that vary in the radial direction. This study also aims to obtain the analytical solution of the strain gradient model presented by Lam for torsional vibration response, in a simple manner, for different rigid or restrained boundary conditions. The torsion angle of a functionally graded nanotube is defined by an infinite Fourier series. Then, the Stokes’ transformation is applied to force the boundary conditions to the desired state. An eigenvalue problem is established with the help of the two systems of equations obtained. This eigenvalue problem, which includes deformable springs at both ends of the nanotube, appears as a general analytical solution that can find torsional vibration frequencies. It is shown that the vibrational responses can be significantly influenced by the through-radius gradings of material, material length scale parameters and deformable springs of the functionally graded nanotubes and consequently can be predicted by giving proper values to torsional spring parameters.  相似文献   

    

Mustafa Okumuş 《Molecular Crystals and Liquid Crystals》2016,625(1):117-125

The 6CB/8CB/8OCB liquid crystal mixture has been studied by Differential Scanning Calorimetry (DSC), polarised optic microscopy (POM), Semiconductor Characterization System, and Ultra-violet spectrophotometry (UV). DSC and POM results indicate that the 6CB/8CB/8OCB mixture exhibits liquid crystalline properties. The capacitance-voltage and conductance-voltage measurements were performed in the frequency range of 200-500 kHz and in the temperature range of 30oC–50oC. The 6CB/8CB/8OCB mixture showed an extremely large positive dielectric anisotropy. The molar absorptivity ? for the 6CB/8CB/8OCB mixture was calculated and found to be higher than the absorptivity values of the binary mixtures due to the alkyl chain length with H-aggregation.  相似文献   

    

Anis Allagui  Hussain Alawadhi  Mustafa Alkaaby  Mounir Gaidi  Khalid Mostafa  Yacoub Abdulaziz 《physica status solidi (a)》2016,213(1):139-145

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Mohammad W. Amer;Eman M. Khdeir;Francesco Barzagli;Mustafa A. Taha;Heba M. Alsalti;Elias N. Ibrahim;Rahaf A. Almassi;Ahmad R. Hasoneh;Mohammed Y. Rasheed;Raid Al-Jawasrah; 《Crystal Research and Technology》2024,43(6):e14469

This study explores the adsorption potential of hydrothermally treated waste derived algal biomass for removing methylene blue (MB) dye. Synthesizing a modified hydrochar through hydrothermal carbonization (150°C, 35 bar) followed by NaOH modification, we observed enhanced thermal stability and distinctive chemical changes. Optimal conditions were determined at pH 6 and 1 h contact time. Soluble salts with cations were identified as impacting adsorption efficiency, with increased interference for higher cation charges. Thermodynamic parameters (ΔG, ΔH, and ΔS) indicated a spontaneous and exothermic process, the calculated values (−5.417 to −6.907 kJ mol−1, −29.0 kJ mol−1, −73.8 J K−1 mol−1) aligned with this behavior. Adsorption isotherms favored the Freundlich model, revealing heterogeneous multilayer adsorption, with a maximum capacity of 97%. Kinetic studies supported the pseudo-first-order model. This detailed exploration provides insights into thermodynamics, kinetics, and the impact of adsorption parameters on MB removal, emphasizing the practicality of alkaline-modified hydrochar as an effective, sustainable adsorbent.  相似文献   

    

Ali Rehman;Ma Chau Khun;Hammad Alotaibi;Mustafa Inc; 《ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik》2024,104(5):e202300556

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Azzam Aladool  Mustafa Aziz  David Wright 《physica status solidi b》2019,256(7)

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Matthias Schiedel  Mustafa Moroglu  David M. H. Ascough  Anna E. R. Chamberlain  Jos J. A. G. Kamps  Angelina R. Sekirnik  Stuart J. Conway 《Angewandte Chemie (International ed. in English)》2019,58(50):17930-17952

Epigenetics is currently the focus of intense research interest across a broad range of disciplines due to its importance in a multitude of biological processes and disease states. Epigenetic functions result partly from modification of the nucleobases in DNA and RNA, and/or post‐translational modifications of histone proteins. These modifications are dynamic, with cellular machinery identified to modulate and interpret the marks. Our focus is on bromodomains, which bind to acetylated lysine residues. Progress in the study of bromodomains, and the development of bromodomain ligands, has been rapid. These advances have been underpinned by many disciplines, but chemistry and chemical biology have undoubtedly played a significant role. Herein, we review the key chemistry and chemical biology approaches that have furthered our study of bromodomains, enabled the development of bromodomain ligands, and played a critical role in the validation of bromodomains as therapeutic targets.  相似文献   

    

Mustafa Inc  Hamdy I. Abdel‐Gawad  Mohammad Tantawy  Abdullahi Yusuf 《Mathematical Methods in the Applied Sciences》2019,42(7):2455-2464

In this article, the generalized unified method (GUM) is used for finding multiwave solutions of the coupled Whitham‐Broer‐Kaup (WBK) equation with variable coefficients. Which describes the propagation of of shallow water waves. Here, we study the effects of the indirect nonlinear interaction of one‐, two‐ and three‐solitonic similaritons on the behavior of propagation of waves, in quasi‐periodic distributed system. This study can unable us to control the dynamics of type soliton (soliton, anti‐soliton) similaritons waves in dispersive waveguides. To give more physical insight to the obtained solutions, they are shown graphically. Their different structures are depicted by taking appropriate arbitrary functions. Further, with the suitable parameters, the indirect nonlinear interaction between two and three‐soliton waves are shown weal, in the sense that their amplitude does not blow up. Moreover, because of the importance of conservation laws Cls and stability analysis SA in the investigation of integrability, internal properties, existence, and uniqueness of a differential equation, we compute the Cls via multiplier technique and stability analysis via the concept of linear stability analysis for the WBK equations using the constant coefficients.  相似文献   

    

Engin Arslan  Mustafa K. Öztürk  Süleyman Özçelik  Ekmel Özbay 《哲学杂志》2019,99(14):1715-1731

The influence of the LT-AlN(NL) growth times on the mosaic structure parameters of the AlN layer grown on the LT-AlN(NL)/6H-SiC structures as well as the dislocation densities and the strain behaviours in the AlN epilayers has been investigated using XRD measurements. The growth times of the LT-AlN(NL) were changed to 0, 60, 120, 180, and 240?s. We observed that the mosaic structure parameters of the AlN epilayers were slightly affected by the LT-AlN(NL) growth times. However, the dislocation densities in the AlN layer are affected by the growth times of the LT-AlN(NL) layer. The highest edge dislocation density (5.48?×?10¹⁰?±?2.3?×?10⁹?cm^?2) was measured for the sample in which 120?s grown LT-AlN(NL) was used. On the other hand, highest screw type dislocation density (1.21?×?10¹⁰?±?1.7?×?10⁹?cm^?2) measured in the sample E that contains 240?s growth LT-AlN(NL). The strain calculation results show that the samples without LT-AlN(NL) suffered maximum compressive in-plane strain (?10.9?×?10^?3?±?1.8?×?10^?4), which can be suppressed by increasing the LT-AlN(NL) growth times. The out-of-plane strain also has a compressive character and its values increase with LT-AlN(NL) growth times between 60 and 180?s. Same out-of-plane strain values were measured for the LT-AlN(NL) growth times of 180 and 240?s. Furthermore, the form of the biaxial stress in the AlN epilayer changed from compressive to tensile when the LT-AlN(NL) growth times were greater than 120?s.  相似文献   

    

Shailendra K. Saxena  Scott R. Smith  Mustafa Supur  Richard L. McCreery 《Advanced Optical Materials》2019,7(20)

Eleven bilayer molecular junctions (MJs) consisting of two different 5–7 nm thick molecular layers between conducting contacts are investigated to determine how orbital energies and optical absorbance spectra of the oligomers affect the photocurrent (PC) response, the direction of photoinduced charge transport, and maximum response wavelength. Photometric sensitivity of 2 mA W⁻¹ and a detection limit of 11 pW are demonstrated for MJs, yielding an internal quantum efficiency of 0.14 electrons per absorbed photon. For unbiased MJs, the PC tracks the absorption spectrum of the molecular layer, and is stable for >5 h of illumination. The organic/organic (O/O) interface between the molecular layers within bilayer MJs is the primary determinant of PC polarity, and the bilayer MJ mechanism is conceptually similar to that of a single O/O heterojunction studied in bilayers of much greater thickness. The charge transport direction of the 11 MJs is completely consistent with hole‐dominated transport of photogenerated carriers. For MJs illuminated while an external bias is applied, the PC greatly exceeds the dark current by factors of 10² to 10⁵, depending on bias, bilayer structure, and wavelength. The bilayer MJs are amenable to flexible substrates, and may have applications as sensitive, wavelength‐specific photodetectors.  相似文献