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排序方式: 共有479条查询结果,搜索用时 15 毫秒
471.
Rahman M.T. Chih-Huang Lai Vokoun D. Shams N.N. 《IEEE transactions on magnetics》2007,43(6):2133-2135
A simple approach is proposed for fabrication of percolated perpendicular media (PPM). Nano pore array with pore diameter of 12-15 nm and different pore densities has been prepared by anodizing aluminum on silicon wafers. The pore density increases from 3.2times1010 cm-2 to 11.0times1010 cm-2 with the decrease in anodizing voltage from 30 to 10 V. Then, Pt (7 nm)/{Co (0.5 nm)/Pt (2) nm}5 multilayers are deposited onto this porous anodized alumina (AAO) by sputtering. The pore size is reduced to 10-12 nm after deposition of magnetic layers. The Co/Pt multilayers on AAO exhibit perpendicular magnetic anisotropy, squareness ratios of unity, and negative nucleation fields. The perpendicular coercivity increases linearly with the increase in pore density due to the pinning effect imposed by the pores, which is consistent with theoretical calculation for PPM 相似文献
472.
Fayaz Ahmad Mir Ehsan Ullah Raghvendra Mall Ahmad Iskandarani Tareq A. Samra Farhan Cyprian Aijaz Parray Meis Alkasem Ibrahem Abdalhakam Faisal Farooq Abdul-Badi Abou-Samra 《International journal of molecular sciences》2022,23(17)
Background: Obesity coexists with variable features of metabolic syndrome, which is associated with dysregulated metabolic pathways. We assessed potential associations between serum metabolites and features of metabolic syndrome in Arabic subjects with obesity. Methods: We analyzed a dataset of 39 subjects with obesity only (OBO, n = 18) age-matched to subjects with obesity and metabolic syndrome (OBM, n = 21). We measured 1069 serum metabolites and correlated them to clinical features. Results: A total of 83 metabolites, mostly lipids, were significantly different (p < 0.05) between the two groups. Among lipids, 22 sphingomyelins were decreased in OBM compared to OBO. Among non-lipids, quinolinate, kynurenine, and tryptophan were also decreased in OBM compared to OBO. Sphingomyelin is negatively correlated with glucose, HbA1C, insulin, and triglycerides but positively correlated with HDL, LDL, and cholesterol. Differentially enriched pathways include lysine degradation, amino sugar and nucleotide sugar metabolism, arginine and proline metabolism, fructose and mannose metabolism, and galactose metabolism. Conclusions: Metabolites and pathways associated with chronic inflammation are differentially expressed in subjects with obesity and metabolic syndrome compared to subjects with obesity but without the clinical features of metabolic syndrome. 相似文献
473.
Yuming Chu Naila Rafiq Mudassir Shams Saima Akram Nazir Ahmad Mir Humaira Kalsoom 《计算机、材料和连续体(英文)》2021,66(1):275-290
In this article, we construct the most powerful family of simultaneous
iterative method with global convergence behavior among all the existing methods in literature for finding all roots of non-linear equations. Convergence analysis proved that the order of convergence of the family of derivative free
simultaneous iterative method is nine. Our main aim is to check out the most
regularly used simultaneous iterative methods for finding all roots of non-linear
equations by studying their dynamical planes, numerical experiments and CPU
time-methodology. Dynamical planes of iterative methods are drawn by using
MATLAB for the comparison of global convergence properties of simultaneous
iterative methods. Convergence behavior of the higher order simultaneous iterative methods are also illustrated by residual graph obtained from some numerical
test examples. Numerical test examples, dynamical behavior and computational
efficiency are provided to present the performance and dominant efficiency of
the newly constructed derivative free family of simultaneous iterative method
over existing higher order simultaneous methods in literature. 相似文献
474.
The extraction of heavy metals from industrial effluents using efficient adsorbents is crucial for wastewater treatment and beneficial for metal recycling. In this study, the removal of Cu(II) from an acidic solution by commercial resins Dowex G-26 and Puromet™ MTS9570 was investigated. The influences of contact time, solution concentration, pH, temperature, and a resin dosage on the adsorption process were studied with batch technique. The optimum adsorption conditions were obtained at a concentration of 1100 mg/L Cu, contact time of 30 min, pH 3.5, and resin dosage of 0.025 g/ml for the removal of 99.9% and 90% of copper ions by G-26 and MTS9570, respectively. The experimental data of copper adsorption were analyzed using the Langmuir, Freundlich, and Temkin isotherm models. The highest metal uptakes of 41.67 and 37.70 mg/g were observed for Dowex G-26 and MTS9570, respectively. It was found that both resins had higher adsorption capacities than the substances reported in the literature. The adsorption kinetic studies showed that the copper adsorption process could be better described by the pseudo-second order model. Adsorption occurs spontaneously under endothermic conditions, which indicates the endothermic nature of the process. 相似文献
475.
Din Nizamud Waheed Abdul Ullah Shamsher Amin Noor Ul Srivastava Gautam Ullah Farhan Lin Jerry Chun-Wei 《International Journal of Information Security》2023,22(4):1055-1073
International Journal of Information Security - The growth of media services, multimedia conferencing, interactive distance learning, and distributed interactive simulations is becoming more... 相似文献
476.
Origami has become an increasingly popular geometry in thermal engineering, namely, heat regulatory applications such as heat sinks and radiators. In this study, the radiative heating and radiative and natural convective cooling of three origami geometries (W-fold, Miura Ori (1), and Miura Ori (2)) made of heavy-duty aluminum foil under a radiative heater with different powers (800, 1600, and 2400 W) and different compression lengths (0.15, 0.25, 0.35, and 0.45 m) were investigated. It was found that the Miura Ori (1) and Miura Ori (2) geometries have three to four times high-temperature differences (the maximum temperature at the end of the heating process minus the initial temperature) than the W-fold geometry. The Miura Ori (2) and Miura Ori (1) geometries produced high heat capacity enhancements of 1.2–3.2 times at high compression lengths that showed great potential for applications such as solar steam generators. The overall heat transfer coefficient for cooling can be controlled by changing the compression length of the origami geometry, allowing for dynamic surface temperature controls. This parameter decreases by up to 25.3%, 22.6%, and 45.9% for W-fold, Miura Ori (1), and Miura Ori (2), respectively, in comparison to their flat states. 相似文献
477.
Aqueous ruthenium was detected in real-time under ambient conditions using microwave-assisted laser-induced breakdown spectroscopy (MW-LIBS). A 10 mJ laser energy and 750 W microwave power were directed at an open liquid jet sample of ruthenium. It was observed that, for liquid flow, the coupling efficiency between the microwave and the laser-induced plasma was limited to 43%. The improvement in the ruthenium's signal-to-noise ratio with MW-LIBS, with respect to LIBS, was 76-fold. Based on MW-LIBS, the limit of detection for aqueous ruthenium was determined to be 957 ± 84 ppb. 相似文献
478.
479.
Nadia Sobhy Ibrahim Hoda Zaki Shams Fatma Abd El-Maksoud Abd El-Aal Mohamed Hilmy Elnagdi 《Advanced Synthesis \u0026amp; Catalysis》1987,329(4):552-556
The reaction of 3-amino-2,4-diethoxycarbonylcrotononitrile with cinnamonitrile derivatives afforded the pyrimidines 5a--d and not the pyridines 4 as expected from literature. Similarly pyrimidines 5e--h were produced when 3-amino-2,4-dicyanocrotononitrile was treated with the same reagent. The structure was established based on MS and high resolution 1H-n.m.r. spectroscopy. 相似文献