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991.
Rençber Seda Gündoğdu Evren Köksal Karayıldırım Çinel Başpınar Yücel 《Iranian Polymer Journal》2021,30(6):569-582
Iranian Polymer Journal - Mucoadhesive gel formulations containing pentoxifylline (PTX)-loaded nanoparticle (NP) for the treatment of genital ulcer were prepared and evaluated. In that context,... 相似文献
992.
Ömer Güler Mükremin Tekeli Mustafa Taşkın Seval Hale Güler I.S. Yahia 《Ceramics International》2021,47(1):521-533
There are many production methods for graphene production. One of the most successful production methods in terms of scale-up is liquid phase exfoliation (LPE) method. In this study, after optimizing the sonication time and sonication power that are effective in the production to increase the efficiency of the LPE method, the experiments were continued at moderate sonication powers and the effect of liquid media, another important parameter, was examined. In this study, hexagonal graphite powders were subjected to direct liquid phase exfoliation process by using different liquid media (N-Methyl-2-Pyrrolidone (NMP), N,N-Dimethylformamide (DMF), ethanol, 2-propanol, acetone, methanesulfonic acid, ethanol + Sodium dodecyl sulphate (SDS), 2-propanol + SDS) and the obtained samples were characterized. As a result of the characterization, the liquid media with the highest efficiency was determined to be NMP. Besides, it was observed that a new hybrid solvent obtained by adding a surfactant such as SDS into low-cost and environmentally friendly liquid media such as ethanol and 2-propanol showed a higher efficiency than NMP. It was observed that 3–5 layer graphene ranged between 15 and 19 wt% in either graphene produced by using hybrid solvents containing NMP or SDS. The amount of double or single-layer graphene was negligibly small. The production with the lowest efficiency was observed in the use of acetone. The produced graphenes were dispersed in the liquid and their sedimentation time was observed. The sedimentation time of graphenes, produced using NMP and SDS-doped hybrid solvents, in liquid was more than 120 days. The sedimentation time of graphene produced using acetone was less than 20 days. In the use of graphene as a reinforcing material or adsorbent, large amounts of graphene are needed. In such applications, mass production of graphene is important rather than the number or quality of sheets of graphene. Therefore, optimization of production parameters of LPE method, which is suitable for mass production, is significance. 相似文献
993.
Wireless Networks - Inherent multicarrier transmission mechanism of the universal filtered multicarrier (UFMC) waveform engenders the problem of high peak-to-average power ratio (PAPR). Since it is... 相似文献
994.
Erişir Ersoy Ararat Özge Bilir Oğuz Gürkan 《Metallurgical and Materials Transactions A》2022,53(3):850-860
Metallurgical and Materials Transactions A - The typical final microstructure of bearing steels is composed of coarse carbides in a martensitic matrix due to coarse carbides in the initial... 相似文献
995.
Kuru Mehmet Şaşmaz Kuru Tuğba 《Journal of Materials Science: Materials in Electronics》2022,33(23):18587-18606
Journal of Materials Science: Materials in Electronics - In this study, Mg0.75Zn0.25CrxFe2?xO4 (x?=?0.4, 0.5) (MZC) nanoferrites were prepared by chemical co-precipitation. The... 相似文献
996.
Multimedia Tools and Applications - The number of vehicles and turning movements at roundabouts provide important information for planning, design and operational analysis of roundabouts. The... 相似文献
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Fabrication of starch‐g‐poly(l‐lactic acid) biocomposite films: Effects of the shear‐mixing and reactive‐extrusion conditions 下载免费PDF全文
In this study, we developed a new approach for the fabrication of a green poly(l ‐lactic acid)‐grafted starch (St‐g‐PLA) copolymer and nanocomposite (St‐g‐PLA/organoclay)‐based films via shear‐mixing and reactive‐extrusion systems. The chemical and physical structures, thermal behavior, and morphology of the synthesized blends and some other parameters were examined by Fourier transform infrared spectroscopy and 13C cross‐polarization/magic angle spinning NMR spectroscopy, X‐ray diffraction, thermogravimetric analysis–derivative thermogravimetry, and scanning electron microscopy, respectively. Significant increases in the mechanical and permeability properties were evident in the high value of grafted poly(lactic acid) molar percentages and high exfoliation of organoclay. The biodegradability of films were investigated under aerobic composting conditions through the measurement of the temperature, moisture, pH, consumed O2 value, and carbon dioxide produced. This new strategy mainly improved the good adhesion between both phases, and it was an interesting method for the production of environmentally friendly biocomposites that could easily be scaled up for commercial production with the potential for replacing petroleum‐based plastics. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44490. 相似文献