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841.
Safia Anjum M. Shahid RafiqueM. Khaleeq-ur-Rahman K. SirajArslan Usman S.I. Hussain S. Naseem 《Journal of magnetism and magnetic materials》2012,324(5):711-716
In this paper we present the effect of low substrate temperature on structural, morphological, magnetic and optical properties of Ba-hexaferrite thin films. Films were deposited on single crystal Silicon (1 0 0) substrate employing the Pulsed Laser Deposition (PLD) technique. The structural, morphological, magnetic and optical properties are found to be strongly dependent on substrate temperature. The low substrate temperatures (room temperature to 200 °C) restrict the formation of larger grains. For the higher substrate temperature i.e., 400 °C, the grain size of the deposited thin film are much larger. The film grown at low substrate temperature do not show any anisotropy. As the substrate temperature is increased, the easy axis of the films alinged itself in the direction parallel to the film plane whereas the hard axis remained in the perpendicular direction. The higher substrate temperature caused the uniaxial magnetic anisotropy, which is very important in magnetic recording devices. The saturation magnetization and optical band gap energy values of 62 emu/cc and 1.75 eV, respectively, were achieved for the film of thickness 500 nm deposited at 400 °C. Higher values of coercivity, squareness and films thickness are associated with the growth of larger grains at higher substrate temperature. 相似文献
842.
Iris recognition technology recognizes a human based on his/her iris pattern.However,the accuracy of the iris recognition technology depends on accurate iris localization.Localizing a pupil region in the presence of other low-intensity regions,such as hairs,eyebrows,and eyelashes,is a challenging task.This study proposes an iris localization technique that includes a localizing pupillary boundary in a sub-image by using an integral projection function and two-dimensional shape properties(e.g.,area,geometry,and circularity).The limbic boundary is localized using gradients and an error distance transform,and the boundary is regularized with active contours.Experimental results obtained from public databases show the superiority of the proposed technique over contemporary methods. 相似文献
843.
Iman Fatima Akhtar Rasul Shahid Shah Malik Saadullah Nayyer Islam Ahmed Khames Ahmad Salawi Muhammad Masood Ahmed Yosif Almoshari Ghulam Abbas Mohammed A. S. Abourehab Sajid Mehmood Khan Zunera Chauhdary Meshal Alshamrani Nader Ibrahim Namazi Demiana M. Naguib 《Molecules (Basel, Switzerland)》2022,27(9)
The occurrence of fungal infections has increased over the past two decades. It is observed that superficial fungal infections are treated by conventional dosage forms, which are incapable of treating deep infections due to the barrier activity possessed by the stratum corneum of the skin. This is why the need for a topical preparation with advanced penetration techniques has arisen. This research aimed to encapsulate fluconazole (FLZ) in a novasome in order to improve the topical delivery. The novasomes were prepared using the ethanol injection technique and characterized for percent entrapment efficiency (EE), particle size (PS), zeta potential (ZP), drug release, Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and antifungal activity. The FN7 formulation with 94.45% EE, 110 nm PS and −24 ZP proved to be the best formulation. The FN7 formulation showed a 96% release of FLZ in 8 h. FTIR showed the compatibility of FLZ with excipients and DSC studies confirmed the thermal stability of FLZ in the developed formulation. The FN7 formulation showed superior inhibition of the growth of Candida albicans compared to the FLZ suspension using a resazurin reduction assay, suggesting high efficacy in inhibiting fungal growth. 相似文献
844.
Shuaib Urooj Hussain Tousif Ahmad Riaz Imranullah M. Amjad Muhammad Yasin Amna Shakir Imran Kang Dae Joon 《Journal of Solid State Electrochemistry》2023,27(3):715-725
Journal of Solid State Electrochemistry - Nowadays, metal hexacyanoferrate/metal oxide composites have attracted intense interest as an electrode material for supercapacitor applications due to... 相似文献
845.
Shahid Farooq Muhammad Ijaz Khan Faris Alzahrani Aatef Hobiny 《Numerical Methods for Partial Differential Equations》2023,39(2):827-847
Current research models the Al2O3 47nm and Al2O3 36nm nanoparticles transportation through peristalsis with entropy optimization. Conservation laws for mass, momentum and energy are used to model the present flow situation. These equations elaborates the magnetohydrodynamics, Hall, thermal radiation, Joule heating, heat generation and absorption. Convective heat transfer impacts are studied at channel walls. Entropy is modeled in view of thermodynamics second law. Two different expressions for effective viscosity are accounted. Simplification of the modeled equations is done through lubrication assumptions. Solution for momentum equation is obtained analytically and for numerically for temperature equation. Built-in shooting procedure is utilized to obtain the desired numerical results. Later on these obtained results are used to sketch and discussed the flow quantities of interest for the influential parameters accounted in the problem. 相似文献
846.
Shahid Aziz Faheem Akhter Hidayat Hussain Jiguo Liu Huijiao Yan Li Cui Qixu Chen Wei Cheng Daijie Wang Xiao Wang 《Journal of separation science》2023,46(20):2300306
Bergenia ciliata (haw.) Sternb, the renowned pharmaceutical plant in Jammu and Kashmir of Pakistan, is widely applied in treating different illnesses including diabetes, diarrhea, and vomiting. This work employed an efficient one-step inner-recycling counter-current chromatography for preparative separating and purifying compounds with similar partition coefficients from the rhizome of Bergenia ciliate (haw.). Five compounds, including quercetin rhamnodiglucoside ( 1 ), quercetin-3-O-rutinoside ( 2 ), bergenine ( 3 ), kaempferol ( 4 ), and palmatic acid ( 5 ), were successfully separated using the optimized biphasic solvent system that contained ter-butylmetylether/n-butanol/acetonitrile/water (2:2:1:5, v/v) with the purities over 98%. Mass spectrometry and nuclear magnetic resonance were conducted for structural identification. As a result, our proposed strategy might be applied in separating compounds with similar partition coefficients, which was advantageous with regard to the less solvent and time consumption, and the increased number of theoretical plates. 相似文献
847.
Brittany P. Rickard Xianming Tan Suzanne E. Fenton Imran Rizvi 《Photochemistry and photobiology》2023,99(2):793-813
Per- and polyfluoroalkyl substances (PFAS) are widespread environmental contaminants linked to adverse outcomes, including for female reproductive biology and related cancers. We recently reported, for the first time, that PFAS induce platinum resistance in ovarian cancer, potentially through altered mitochondrial function. Platinum resistance is a major barrier in the management of ovarian cancer, necessitating complementary therapeutic approaches. Photodynamic therapy (PDT) is a light-based treatment modality that reverses platinum resistance and synergizes with platinum-based chemotherapy. The present study is the first to demonstrate the ability of photodynamic priming (PDP), a low-dose, sub-cytotoxic variant of PDT, to overcome PFAS-induced platinum resistance. Comparative studies of PDP efficacy using either benzoporphyrin derivative (BPD) or 5-aminolevulinic acid-induced protoporphyrin IX (PpIX) were conducted in two human ovarian cancer cell lines (NIH:OVCAR-3 and Caov-3). BPD and PpIX are clinically approved photosensitizers that preferentially localize to, or are partly synthesized in, mitochondria. PDP overcomes carboplatin resistance in PFAS-exposed ovarian cancer cells, demonstrating the feasibility of this approach to target the deleterious effects of environmental contaminants. Decreased survival fraction in PDP + carboplatin treated cells was accompanied by decreased mitochondrial membrane potential, suggesting that PDP modulates the mitochondrial membrane, reducing membrane potential and re-sensitizing ovarian cancer cells to carboplatin. 相似文献
848.
Syed Dilshad Alam Mirza Adil Beg Muralidhararao Bagadi Marcello Locatelli Zeid A. ALOthman Mohd Mustaqeem Imran Ali 《Journal of separation science》2023,46(21):2300582
The extraction of berberine was carried out from Berberis vulgaris, Berberis aquifolium, and Hydrastis canadensis plants using ethanol and water (70:30, v/v). The extracted berberine was characterized by ultraviolet-visible and Fourier-transform infrared spectroscopy. The purity of berberine was ascertained by thin-layer chromatography using n-propanol-formic acid-water (95:1:4) and (90:1:9) solvents. hRf values were in the range of 44–49 with compact spots (diameter 0.2–0.4 cm). HPLC was carried out using ammonium acetate buffer and acetonitrile in gradient mode with Zodiac (4.6 × 150 mm, 3 μm) column. The flow rate was 1.0 mL/min and detection was at 220 nm. The values of separation and resolution factors of the standard and the extracted berberine were in the range of 1.13–1.16 and 1.40–1.71, respectively. A comparison has shown that both thin-layer chromatography and high-performance liquid chromatography (HPLC) methods found applications in different situations and requirements. The extracted berberine samples were used to treat Leishmaniosis and the results showed better activity of berberine in comparison to the standard drug Amphotericin B. Briefly, the reported research is a novel and may be used to extract berberine from plants, separation and identification of berberine by thin layer chromatography and HPLC and to treat Leishmaniosis. 相似文献
849.
Ullah Asad Zaman Shahid Hamraz Anila Muzammal Muniba 《The European physical journal. E, Soft matter》2023,46(8):1-8
The European Physical Journal E - In this article, we experimentally investigate the nonlinear behaviour of a viscoplastic film flow down an inclined plane. We focus on the nonlinear instabilities... 相似文献
850.