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961.
A high power enzymatic fuel‐cell was anticipated by using a recently developed glucose oxidase (GOx) immobilized bio‐anode, a conventional platinum?carbon based cathode and a popular high performance 125 μ‐thick perfluorosulfonic acid‐type proton exchange membrane (i. e. Nafion® 115). Unexpected current density decay from 2.13 mA cm?2 to 0.28 mA cm?2 was observed within 2 hours. Polarization measurements and AC impedance analysis indicated that loss of performance was linked to the membrane behavior. Ion exchange between buffer solution and membrane was perceived as the main cause for the fast performance loss. Saturation of the membrane with the cation in the buffer solution diminished proton transfer needed for cathode reaction. Charge transfer resistances, obtained from AC impedance data, increased with time substantially due to cation exchange within membrane. Replacement of membrane with the same enzyme electrode and cathode has resulted 100 % current density recovery on the fuel cell performance. It was concluded that a membrane, not affected by the buffer cations, was required for successful enzymatic fuel cell applications. 相似文献
962.
Eratr Mehmet Yldrm Metin Giray Elife Sultan Yaln Serap 《Monatshefte für Chemie / Chemical Monthly》2020,151(4):625-636
Monatshefte für Chemie - Chemical Monthly - A series of novel coumarins with 2-amino-3-cyanoselenophen-5-yl unit on C-3 have been synthesized. These compounds prepared easily at room... 相似文献
963.
Nonlinear Dynamics - Nonlinearities in rotating systems have been seen to cause a wide variety of rich phenomena; however, the understanding of these phenomena has been limited because numerical... 相似文献
964.
Adun Humphrey Adedeji Michael Dagbasi Mustafa Bamisile Olusola Senol Mehmet Kumar Ravinder 《Journal of Thermal Analysis and Calorimetry》2021,145(3):1413-1429
Journal of Thermal Analysis and Calorimetry - Hybrid nanofluids have been known to provide perceptibly increased heat transfer characteristics over conventional fluid, and so have been... 相似文献
965.
Hatice Busra Tinmaz Irem Arslan Mehmet Atilla Tasdelen 《Journal of polymer science. Part A, Polymer chemistry》2015,53(14):1687-1695
Well‐defined star polymers consisting of tri‐, tetra‐, or octa‐arms have been prepared via coupling‐onto strategy using photoinduced copper(I)‐catalyzed 1,3‐dipolar cycloaddition click reaction. An azide end‐functionalized polystyrene and poly(methyl methacrylate), and an alkyne end‐functionalized poly(ε‐caprolactone) as the integrating arms of the star polymers are prepared by the combination of controlled polymerization and nucleophilic substitution reactions; whereas, multifunctional cores containing either azide or alkyne functionalities were synthesized in quantitatively via etherification and ring‐opening reactions. By using photoinduced copper‐catalyzed azide–alkyne cycloaddition (CuAAC) click reaction, reactive linear polymers are simply attached onto multifunctional cores to form corresponding star polymers via coupling‐onto methodology. The chromatographic, spectroscopic, and thermal analyses have clearly demonstrated that successful star formations can be obtained via photoinduced CuAAC click reaction. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1687–1695 相似文献
966.
Central European Journal of Operations Research - Airline alliances provide more flights, include different destinations, and maximize revenues. In an alliance, collaborating airlines can offer... 相似文献
967.
Moore Keegan J. Kurt Mehmet Eriten Melih McFarland D. Michael Bergman Lawrence A. Vakakis Alexander F. 《Nonlinear dynamics》2018,93(3):1559-1577
Nonlinear Dynamics - We consider the response of a single-degree-of-freedom, linear oscillator (LO) coupled to a vibro-impact (VI) nonlinear energy sink (NES), and subject to an impulsive load. A... 相似文献
968.
Gokhan Acik Cagatay Altinkok Mehmet Atilla Tasdelen 《Journal of polymer science. Part A, Polymer chemistry》2018,56(22):2595-2601
The syntheses of polypropylene-graft-poly(l -lactide) copolymers (PP-g-PLAs) via copper (I)-catalyzed azide-alkyne cycloaddition “click” reaction (CuAAC) using azide side-chain functionalized polypropylene (PP-N3) and alkyne end-functionalized poly(l -lactide) (PLA-Alkyne) were reported. The CuAAC was then applied to azide and different feeding ratios of alkyne functional polymers to give PP-g-PLAs that were characterized by FTIR, 1H-NMR, GPC, DSC, and WCA measurements. The CuAAC click reaction was achieved by two different feeding ratio (PP-N3:PLA-Alkyne = 1:5 and 1:10) and thermal, biodegradable, and surface properties of obtained graft copolymers were investigated. The molar ratio of PLA were calculated as 72.7 (PP-g-PLA-1) and 78.4% (PP-g-PLA-2) by 1H-NMR spectroscopy. The water contact angle (WCA) values of PP-g-PLA-1 (81o ± 1.3) and PP-g-PLA-2 (75o ± 1.6) copolymers were compared with commercial chlorinated polypropylene (PP-Cl) (90o ± 1.0), suggesting a more hydrophilic nature of desired graft copolymers produced. Conversely, the enzymatic biodegradation studies revealed that the weight losses of graft copolymers were determined as 13.6 and 22.1%, which is about 4% for commercial PP-Cl sample. Thus, it was clear that this simple and facile method was effective in promoting biodegradation of commercial polypropylene and attractive particularly for worldwide environmental remediation goals. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 2595–2601 相似文献
969.
Optimization Letters - In this paper, we consider a store that sells two vertically differentiated items that might substitute each other. These items do not only differ in quality and price, but... 相似文献
970.
The present investigation is emphasized on the effect of various combustion agents on the crystal properties, surface microstructure, and oxygen ion conductivity of 20% mole-Sm doped ceria (Ce0.80Sm0.20O1.90/SDC20) ceramics as solid electrolyte for IT-SOFCs. The most widely used combustion agents for engineering ceramic production as ethylene glycol, diethylene glycol, triethylene glycol, L-alanine, L-valine, glycine, citric acid monohydrate, urea, and EDTA-citric acid were compared in terms of SDC20 properties. X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and electrochemical impedance spectroscopy (EIS) were used to determine the microstructure properties, crystal structure and ionic conductivity of SDC20 powder. XRD pattern of the ceramics revealed the formation of single-phase fluorite structure. According to the results of electrochemical analysis, the maximum total ionic conductivity was observed in SDC20 electrolyte synthesized using triethylene glycol as the fuel among all the synthesized electrolytes (5.72 x 10–2 S.cm–1). 相似文献