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71.
Wireless Networks - This paper studies enhancing non-orthogonal multiple access (NOMA) spectral efficiency (SE) through optimizing the assigned power to each NOMA user depending on their channel... 相似文献
72.
73.
Aristides D. Tagalakis Vignesh Jayarajan Ruhina Maeshima Kin H. Ho Farhatullah Syed Lin-Ping Wu Ahmad M. Aldossary Mustafa M. Munye Talisa Mistry Olumide Kayode Ogunbiyi Arturo Sala Joseph F. Standing Seyed M. Moghimi Andrew W. Stoker Stephen L. Hart 《Advanced functional materials》2021,31(37):2104843
74.
Akin Mustafa Günsel Armağan Bilgiçli Ahmet T. Tüzün Burak Arabaci Gulnur Şaki Neslihan Yarasir M. Nilüfer 《Protection of Metals and Physical Chemistry of Surfaces》2020,56(3):609-618
Protection of Metals and Physical Chemistry of Surfaces - Corrosion inhibition effects of water-soluble peripheral substituted cobalt, copper and zinc metallophthalocyanines (CoPc (1), CuPc (2) and... 相似文献
75.
Korkanç Mustafa İnce İsmail Hatır M. Ergün Tosunlar M. Bahadır 《Bulletin of Engineering Geology and the Environment》2021,80(4):3053-3063
Bulletin of Engineering Geology and the Environment - The aim of this study is to determine the extent of deterioration of the limestone on which the İvriz rock monument is engraved. This... 相似文献
76.
Yunus Emre Unsal Mustafa Soylak Mustafa Tuzen 《International Journal of Food Science & Technology》2012,47(6):1253-1258
A new and simple solid‐phase extraction method for the determination of trace levels of sunset yellow has been developed on Diaion HP 2MG column system. The adsorbed sunset yellow on the resin was eluted with 3 mL of methanol and determined by UV–Vis spectrophotometry at 484 nm. Various experimental parameters such as pH, amount of sunset yellow, flow rates of sample and eluent solutions, resin amount, sample volumes, etc. were investigated. The influences of some alkali, alkali earth and transition metals on the recoveries of sunset yellow were investigated. The recovery values for sunset yellow were higher than 95%. Preconcentration factor was found as 150. The detection limit (three sigma) of the reagent blank for sunset yellow was 5.2 μg L?1. The relative standard deviations (RSD) of the procedure were found as 3.9%. The validation of the presented procedure was performed by the method of standard addition. The procedure was successfully applied to the determination of trace levels of sunset yellow in powdered beverage and confectionery products. 相似文献
77.
Kenan Bulcar Mustafa Akyol Gönül Akça Ali Osman Ayaş Mustafa Topaksu Ahmet Ekicibil 《Journal of Superconductivity and Novel Magnetism》2014,27(11):2631-2637
We have worked on the structural and magnetic properties of Zn0.99?xMn0.01Gd x O δ (for x = 0.02, 0.03, and 0.04) compounds prepared by using a sol–gel method. The x-ray diffraction, scanning electron microscopy, and energy dispersive x-ray spectroscopy were used to understand the structural properties of the samples. We observed that co-substitution of Mn (1 %) and Gd (2–4 %) into the ZnO does not change the hexagonal structure. Scanning electron microscope (SEM) images show us that the grain size decreases with the increasing amount of the Gd into the ZnO matrix. The magnetic properties of the samples have been investigated by using magnetic hysteresis and DC susceptibility measurements. The ZMG1 sample shows a weak ferromagnetic behavior at room temperature, whereas the ZMG2 and ZMG3 samples exhibit a paramagnetic nature. Furthermore, it is also found that the magnetizations of the samples decrease with increasing Gd content in the ZnMnO system due to the enhancing interaction between Gd 3+ ions. We summarize that the co-substitution of Mn and Gd into the ZnO generates a room-temperature ferromagnetism, but it still needs more work to obtain strong and high coercivity magnetic loops for applications. 相似文献
78.
The results of current investigation demonstrate that mechanochemical processing can be used to synthesize high purity Fe2B nanocrystals by selecting well-optimized milling conditions, reaction paths and proper starting materials. Microstructure, phase analyses, specific surface area, and magnetic properties of the synthesized nanocrystals were examined by using X-ray diffraction/spectroscopy, electron microscopy, nitrogen adsorption–desorption methods following Brunauer-Emmett-Teller equation and vibrating sample magnetometer techniques, respectively. Removal of MgO impurity phase by leaching the resulting powder in the acetic acid solution yielded single phase Fe2B nanocrystals with the crystallite size and specific surface area of 12.5 nm and 29 m2/g, respectively. Magnetization results clearly indicated the ferromagnetic behavior of Fe2B nanocrystals with saturation magnetization observed around 96.26 emu·g?1. Electron microscope images revealed coaxial/spherical powder shape and morphology of the single-phase Fe2B nanocrystals. 相似文献
79.
Demirhan Citak Sibel Silici Mustafa Tuzen Mustafa Soylak 《International Journal of Food Science & Technology》2012,47(1):107-113
The aim of this study was to determine the levels of copper (Cu), manganese (Mn), zinc (Zn), iron (Fe), cadmium (Cd), lead (Pb), chromium (Cr), nickel (Ni) and selenium (Se) in sunflower honeys obtained from Thrace Region of Turkey. Trace and toxic element determination was performed by atomic absorption spectrometry after microwave digestion. The accuracy of the method was checked by the standard reference material, NIST‐SRM 1515 Apple leaves. The maximum contents of trace and toxic elements in honey samples from Kesan (polluted area) were found as 0.46, 0.82, 1.98, 14.0, 9.86 μg kg?1, 0.48 mg kg?1, 137, 115 and 290 μg kg?1 for Cu, Mn, Zn, Fe, Cd, Pb, Cr, Ni and Se, respectively. 相似文献
80.
Züliyet. Adigüzel Mustafa Anik 《Protection of Metals and Physical Chemistry of Surfaces》2018,54(2):316-324
Nickel (Ni)–Tungsten (W) alloys were electrodeposited galvanostatically (at–10 mA cm–2) on copper substrate with 3 different W contents under the controlled hydrodynamic conditions and then the anodic dissolution behaviors of the alloys were observed by potentiodynamic polarization and electrochemical quartz crystal microbalance (EQCM) techniques. While the structure of the electrodeposited Ni–W alloy with low W content (15.90% W) was crystalline, that of the alloy with high W content (50.80% W) was nano-crystalline according to X-ray diffraction patterns. The increase in the W content of the electrodeposited Ni–W alloy resulted decrease at pH 3 and increase at pH 7 and 12.5 in the anodic currents of the alloy. The pH dependent dissolutions caused electrodeposited alloy surface to have W—enrichment at pH 3 and Ni—enrichment at pH 7 and 12.5. These observations indicated that the selective dissolution of Ni or W was the main mechanism in the anodic dissolution of the electrodeposited Ni–W alloys. The EQCM experiments conducted at pH 7 supported the presence of the selective dissolution mechanism that the anodic dissolution potential of W was 0.42 V lower than that of Ni in the electrodeposited Ni–W alloys. 相似文献