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1.
Khan Saleem Ali Shawkat Khan Arshad Bermak Amine 《Journal of Materials Science: Materials in Electronics》2022,33(1):541-553
Journal of Materials Science: Materials in Electronics - This work presents an interesting fabrication route toward development of pressure sensing patch by utilizing electrically conductive cotton... 相似文献
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Shabnum Shaheen Muhammad Asaf Khan Muhammad Afzal Naeem Muhammad Naveed Shahid Mehwish Jaffer Hanan Mukhtar 《Microscopy research and technique》2022,85(3):1194-1198
The anatomical variations of two plants from the Nyctaginaceae family, Bougainvillea spectabilis and Bougainvillea glabra, were studied using light and scanning electron microscopy methods in this work. Bougainvillea is a dicotyledonous with defensive traits that can withstand extreme (hot and dry) settings; according to the findings, crystal inclusions in cells, woody spines, and an abnormal development pattern are all features that help them survive against predators and are unique to this species. The Bougainvillea plant's leaves are arranged in simple pattern, alternate to each other along stem having an undulate leaves edge and an oval form. The xylem and phloem, palisade, parenchyma midrib, spongy mesophyll, raphide crystal bundles, and trichomes were all visible when bracts and leaves were transversally sectioned and dyed with toluidine blue O (TBO). The presence of crystals was confirmed by a detailed examination of the transverse leaves by using bright-field and cross-polarizing microscopy. Dissecting microscopic examination showed that all the leaves revealed leaves venation pattern that had midvein, lateral veins areoles, and trichomes. Although trichomes have been identified on both sides, a closer look at a cleaned leaf dyed with TBO showed multicellular abundant trichomes on adaxial surface. Stomata complexes were typically found on the abaxial surface of the leaf according to epidermal peels. Present studies also showed that on adaxial side, stomata were lesser in number or were absent and also showed that the morphologies of the pavement cells on the adaxial and abaxial sides of the leaf differed. 相似文献
4.
Naqvi Nuzhat Abbasi Aliya Tabassum Hussain Rasheed Khan M. Aihab Ahmad Basheer 《Wireless Personal Communications》2018,103(2):1563-1585
Wireless Personal Communications - This paper presents a Multilayer Partially Homomorphic Encryption Text Steganography, an invisible approach for covert communication. Existing text-based schemes... 相似文献
5.
Abdullah Ameen Saad Hassan Wasi Khan Shahid Husain Pooja Dhiman Mahavir Singh 《International Journal of Applied Ceramic Technology》2020,17(5):2430-2438
In this work, the physical properties of nanocrystalline samples of La0.7Sr0.3Mn1−xFexO3 (0.0 ≤ x ≤ 0.20) perovskite manganites synthesized by the reverse micelle (RM) technique were explored in detail. The phase purity, crystal structure, and crystallite size of the samples were determined using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. All the samples had rhombohedral crystal structure and crystallite size increased with increase in Fe content in La0.7Sr0.3MnO3. The scanning electron micrographs (SEMs) exhibited smooth surface morphology and nonuniform shape of the particles. The optical properties studied using UV-visible absorption spectroscopy revealed a decrease in the absorbance and optical band gap with an increase in Fe content in La0.7Sr0.3MnO3 compound. The temperature-dependent resistivity measurements revealed semiconducting nature of x = 0 and 0.1 samples up to the studied temperature range, while a metal-to-insulator transition was observed at higher Fe doping. Magnetic studies revealed weak ferromagnetism in all the samples and a reduction in the maximum magnetization with an increase in Fe content. A close correlation between electrical transport and magnetic properties was observed with the doping of Fe ion in La0.7Sr0.3MnO3 at Mn site. These results advocate strong interactions associated with the double exchange mechanism among Fe3+ and Mn3+ ions. 相似文献
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Multimedia Tools and Applications - The arithmetic properties of a finite field have a remarkable impact on the security features of symmetric and asymmetric cryptosystems. Conventionally, in... 相似文献
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The present study investigates the influence of the magnetic field, thermal radiation, Prandtl number, and leading‐edge accretion/ablation on Blasius and Sakiadis flow. The convective boundary condition is employed to investigate the heat transfer. The nondimensional governing boundary layer equations have been solved by the homotopy analysis method for different values of the pertinent parameters. The effects of these parameters on the dimensionless velocity, temperature, skin friction, and Nusselt number are also investigated for various values of relevant parameters affecting the flow and heat transfer phenomena. The most relevant outcomes of the present study are that enhancement in magnetic field strength undermines the flow velocity establishing thinner velocity boundary layer for both Blasius and Sakiadis flows while an increase in accretion/ablation effect at leading‐edge manifests in a deceleration in velocity for Blasius case and the opposite trend is observed for Sakiadis flow. Another important outcome is that an increase in radiation and accretion/ablation at leading‐edge upsurges the fluid temperature leading to enhancement in the thermal boundary layer. For both Blasius and Sakiadis flow, the skin friction coefficient and the heat transfer rate decline with the enhancement of the leading‐edge accretion parameter. The results are compared with the existing data and are found in good agreement. 相似文献
8.
K. Venkatadri S. Abdul Gaffar P. Rajarajeswari V. Ramachandra Prasad O. Anwar Bég B. Md. Hidayathulla Khan 《亚洲传热研究》2020,49(8):4281-4303
Modern magnetic nanomaterial processing operations are progressing rapidly and require increasingly sophisticated mathematical models for their optimization. Stimulated by such developments, in this paper, a theoretical and computational study of a steady magnetohydrodynamic nanofluid over an exponentially stretching/shrinking permeable sheet with melting (phase change) and radiative heat transfer is presented. Besides, wall transpiration, that is, suction and blowing (injection), is included. This study deploys Buongiorno's nanofluid model, which simulates the effects of the Brownian motion and thermophoresis. The transport equations and boundary conditions are normalized via similarity transformations and appropriate variables, and the similarity solutions are shown to depend on the transpiration parameter. The emerging dimensionless nonlinear coupled ordinary differential boundary value problem is solved numerically with the Newton-Fehlberg iteration technique. Validation with special cases from the literature is included. The increase in the magnetic field, that is, the Hartmann number, is observed to elevate nanoparticle concentration and temperature, whereas it dampens the velocity. Higher values of the melting parameter consistently decelerate the boundary layer flow and suppress temperature and nanoparticle concentration. A higher radiative parameter strongly increases temperature (and thermal boundary layer thickness) and weakly accelerates the flow. The increase in the Brownian motion reduces nanoparticle concentrations, whereas a greater thermophoretic body force strongly enhances them. The Nusselt number and Sherwood number are observed to be decreased with an increasing Hartmann number, whereas they are elevated with a stronger wall suction and melting parameter. 相似文献
9.
Md. Abdur Rahim Shamim Mahbub Md. Kamrul Islam Sk. Md. Ali Ahsan Shahed Rana Malik Abdul Rub Anish Khan Md. Anamul Hoque 《Journal of surfactants and detergents》2020,23(2):457-470
Conductometric and cloud point (CP) measurement studies have been performed to investigate the interaction of tetradecyltrimethylammonium bromide (TTAB) and Triton® X-100 (TX-100) with ciprofloxacin hydrochloride (CFH) in different solvents over the temperature range of 295.15–315.15 K. CFH is used for the treatment of various bacterial infections. The observed critical micelle concentration (CMC) values of TTAB were found to be reduced in the presence of electrolytes (Na2SO4/Na3PO4), and this reduction proceeds with the elevation of salt concentration. The order of the CMC of TTAB follows the trend: > >. The observed CMC values of TTAB were found to increase with increasing temperature and decrease with increasing concentration of CFH in aqueous medium. The values of Gibbs free energy of micellization () for the TTAB/TTAB + CFH mixture were found to be negative, implying spontaneous micellization. The estimated CP of TX-100 decreases with increasing concentration of TX-100 in aqueous medium. The CP values first decrease with increasing concentration of CFH and then increase at higher concentration of CFH almost in all cases investigated. The values of free energy of clouding were found to be positive in all cases studied implying that phase separation of TX-100 was nonspontaneous. The other thermodynamic parameters associated with the micellization of TTAB and the phase separation of TX-100 were estimated and explained. 相似文献
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