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51.
General Relativity and Gravitation - In previous work, we established theoretical results concerning the effect of matter shells surrounding a gravitational wave (GW) source, and we now apply these... 相似文献
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Jon E. Carlé Martin Helgesen Natalia K. Zawacka Morten V. Madsen Eva Bundgaard Frederik C. Krebs 《Journal of Polymer Science.Polymer Physics》2014,52(13):893-899
Two low‐band gap polymer series based on benzo[1,2‐b:4,5‐b′]dithiophene (BDT) and dithienylbenzothiadiazole, with different numbers of fluorine substituents on the 2,3,1‐benzothiadiazole unit, have been synthesized and explored in a comparative study of the photochemical stability and operational lifetime in flexible large area roll‐coated bulk heterojunction solar cells. The two polymer series have different side chains on the BDT unit, namely 2‐hexyldecyloxy (BDTHDO) ( P1–P3 ) or 2‐hexyldecylthiophene (BDTTHD) ( P4–P6 ). The photochemical stability clearly shows that the stability enhances along with the number of fluorine atoms incorporated on the polymer backbone. Fabrication of the polymer solar cells based on the materials was carried out in ambient atmosphere on a roll coating/printing machine employing flexible and indium‐tin‐oxide‐free plastic substrates. Solar cells based on the P4–P6 series showed the best performance, reaching efficiencies up to 3.8% for an active area of 1 cm2, due to an enhanced current compared to P1–P3 . Lifetime measurements, carried out according to international summit on OPV stability (ISOS), of encapsulated devices reveals an initial fast decay for P1–P6 in the performance followed by a much slower decay rate, still retaining 40–55% of their initial performance after 250 h of testing under ISOS‐L‐1 conditions. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 893–899 相似文献
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Molecular dynamics simulation of poly(3‐hexylthiophene) helical structure In Vacuo and in amorphous polymer surrounding 下载免费PDF全文
Natalia I. Borzdun Sergey V. Larin Stanislav G. Falkovich Victor M. Nazarychev Igor V. Volgin Alexander V. Yakimansky Alexey V. Lyulin Vikas Negi Peter A. Bobbert Sergey V. Lyulin 《Journal of Polymer Science.Polymer Physics》2016,54(23):2448-2456
The stability of poly(3‐hexylthiophene) (P3HT) helical structure has been investigated in vacuo and in amorphous polymer surrounding via molecular dynamics‐based simulations at temperatures below and above the P3HT melting point. The results show that the helical chain remains stable at room temperature both in vacuo and in amorphous surrounding, and promptly loses its structure at elevated temperatures. However, the amorphous surrounding inhibits the destruction of the helix at higher temperatures. In addition, it is shown that the electrostatic interactions do not significantly affect the stability of the helical structure. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 2448–2456 相似文献
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N‐bromo‐hydantoin grafted polystyrene beads: Synthesis and nano‐micro beads characteristics for achieving controlled release of active oxidative bromine and extended microbial inactivation efficiency 下载免费PDF全文
Mahran Daif Konda Reddy Kunduru Natalia Laout Stanislav Ratner Nurit Beyth Abraham J. Domb 《Journal of polymer science. Part A, Polymer chemistry》2016,54(5):596-610
N‐bromo‐hydantoin and N‐bromo‐5,5′‐dimethylhydantoin conjugated polystyrene beads were synthesized from chloromethyl polystyrene beads which differ in their particles size, crosslinking, nano‐micro porosity, and tunnels size on the surface, in order to study the effect of these parameters on oxidative halogen release and resultant activity, for water purification applications. The synthesized beads were characterized using elemental analysis, FT‐IR, solid state 13C‐NMR, and scanning electron microscope (SEM). The conjugation yield and kinetics in different solvents and bromine loading capacity were studied. The N‐bromoamine polystyrene beads were tested for water decontamination according to NSF 231 protocol. The release of active bromine was analyzed by spectrophotometer using a DPD‐1 kit and also studied the antimicrobial activity against Escherichia coli and MS2 phages. Bead's nano‐micro characteristics were found critical for oxidative halogen release control: rate stabilization and modulation, extension and also influences antimicrobial activity. The synthesized beads exhibited extended and stable release of bromine, 6 and 4 log reduction for E. coli and MS2, respectively for 250 L of passing contaminated water. Thus, N‐halamine hydantoins conjugated polystyrenes, chemically or kinetically release modified should have applications as disinfectants in water purification systems as well as medical field. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 596–610 相似文献