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341.
Jonathan Thorne Aaron Katz Oisin Tong Yushi Yanagita Yoshiharu Tamaki Keegan Delaney 《国际流体数值方法杂志》2016,82(12):979-996
A novel high‐order finite volume scheme using flux correction methods in conjunction with structured finite differences is extended to low Mach and incompressible flows on strand grids. Flux correction achieves a high order by explicitly canceling low‐order truncation error terms across finite volume faces and is applied in unstructured layers of the strand grid. The layers are then coupled together using a source term containing summation‐by‐parts finite differences in the strand direction. A preconditioner is employed to extend the method to low speed and incompressible flows. We further extend the method to turbulent flows with the Spalart–Allmaras model. Laminar flow test cases indicate improvements in accuracy and convergence using the high‐order preconditioned method, while turbulent body‐of‐revolution flow results show improvements in only some cases, perhaps because of dominant errors arising from the turbulence model itself. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
342.
Samia Ghersheen Vladimir Kozlov Vladimir G. Tkachev Uno Wennergren 《Mathematical Methods in the Applied Sciences》2019,42(17):5805-5826
Multiple viruses are widely studied because of their negative effect on the health of host as well as on whole population. The dynamics of coinfection are important in this case. We formulated an susceptible infected recovered (SIR) model that describes the coinfection of the two viral strains in a single host population with an addition of limited growth of susceptible in terms of carrying capacity. The model describes five classes of a population: susceptible, infected by first virus, infected by second virus, infected by both viruses, and completely immune class. We proved that for any set of parameter values, there exists a globally stable equilibrium point. This guarantees that the disease always persists in the population with a deeper connection between the intensity of infection and carrying capacity of population. Increase in resources in terms of carrying capacity promotes the risk of infection, which may lead to destabilization of the population. 相似文献
343.
Enomoto R Iwasaki M Muramatsu K Hayashii H Miyamoto A Itoh R Abe K Abe T Adachi I Aoki M Awa S Belusevic R Emi K Fujii H Fujii K Fujii T Fujimoto J Fujita K Fujiwara N Howell B Iida N Ikeda H Iwasaki H Kajikawa R Kato S Kawabata S Kichimi H Kobayashi M Koltick D Levine I Miyabayashi K Nagai K Nagira T Nakano E Nakabayashi K Nitoh O Noguchi S Ochiai F Ohnishi Y Okuno H Okusawa T Shimozawa K Shinohara T Sugiyama A Sugiyama N Suzuki S Takahashi K Takahashi T Takemoto M Tanimori T Tauchi T 《Physical review D: Particles and fields》1994,50(3):1879-1883
344.
Effect of branching in base polymer on ionic conductivity in hyperbranched polymer electrolytes 总被引:3,自引:0,他引:3
Takahito Itoh Yoshiaki Ichikawa Nobuyuki Hirata Takahiro Uno Masataka Kubo Osamu Yamamoto 《Solid State Ionics》2002,150(3-4):337-345
Novel hyperbranched polymer, poly[bis(diethylene glycol)benzoate] capped with a 3,5-bis[(3′,6′,9′-trioxodecyl)oxy]benzoyl group (poly-Bz1a), was prepared, and its polymer electrolyte with LiN(CF3SO2)2, poly-Bz1a/LiN(CF3SO2)2 electrolyte, was all evaluated in thermal properties, ionic conductivity, and electrochemical stability window. The poly-Bz1a/LiN(CF3SO2)2 electrolyte exhibited higher ionic conductivity compared with a polymer electrolyte based on poly[bis(diethylene glycol)benzoate] capped with an acetyl group (poly-Ac1a), and the ionic conductivity of poly-Bz1a/LiN(CF3SO2)2 electrolyte was to be 7×10−4 S cm−1 at 80 °C and 1×10−6 S cm−1 at 30 °C, respectively. The existence of a 3,5-bis[(3′,6′,9′-trioxodecyl)oxy]benzoyl group as a branching unit present at ends in the base polymer improved significantly ionic conductivity of the hyperbranched polymer electrolytes. The polymer electrolyte exhibited the electrochemical stability window of 4.2 V at 70 °C and was stable until 300 °C. 相似文献
345.
Porphyrins fused with dihydroxylated bicyclo[2.2.2]octadiene at β-positions were quantitatively converted to the corresponding tetrabenzoporphyrins either by treatment with NaH in DMF at 0°C or on boehmite at room temperature. 相似文献
346.
Three‐Way‐Switchable (Right/Left/OFF) Selective Reflection of Circularly Polarized Light on Solid Thin Films of Helical Polymer Blends
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Dr. Yuuya Nagata Makoto Uno Prof. Dr. Michinori Suginome 《Angewandte Chemie (International ed. in English)》2016,55(25):7126-7130
Two poly(quinoxaline‐2,3‐diyl) copolymers bearing miscibility‐enhancing 8‐chlorooctyloxy and (S)‐2‐methylbutoxy or n‐butoxy side chains were synthesized. After annealing in CHCl3 vapor, a polymer‐blend film of these copolymers exhibited selective reflection of right‐handed circularly polarized light (CPL) in the visible region. The handedness of the CPL reflected was completely inverted upon annealing of the film in THF vapor. Annealing in n‐hexane vapor resulted in the phase separation of the polymer blend, which turned the selective reflection off. This three‐way‐switchable reflection, that is, reflection of right‐handed or left‐handed CPL, together with an OFF state, could be observed visually through right‐ and left‐handed CPL filters. 相似文献
347.
Boron Difluoride Complexes of Expanded N‐Confused Calix[n]phyrins That Demonstrate Unique Luminescent and Lasing Properties
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Dr. Masatoshi Ishida Toshihiro Omagari Ryuji Hirosawa Keisuke Jono Dr. Young Mo Sung Dr. Yuhsuke Yasutake Prof. Dr. Hidemitsu Uno Dr. Motoki Toganoh Prof. Dr. Hajime Nakanotani Prof. Dr. Susumu Fukatsu Prof. Dr. Dongho Kim Prof. Dr. Hiroyuki Furuta 《Angewandte Chemie (International ed. in English)》2016,55(39):12045-12049
Complexation of novel multiply N‐confused expanded calix[n]phyrins with boron difluoride afforded a new class of cyclic BODIPY (boron‐dipyrromethene) arrays. The structures of circularly arranged BODIPY subunits linked in an N‐confused fashion give rise to such photophysical properties unique to the macrocycles as redshifted emission wavelengths along with apparent large Stokes shifts, long emission lifetimes, and solid‐state lasing. The DFT calculations support the size‐dependent excited‐state dynamics of the macrocycles. 相似文献
348.
349.
350.
Ayumi Miyao Yuta Mori Takahiro Uno Takahito Itoh Takayuki Yamasaki Akira Koshio Masataka Kubo 《Journal of polymer science. Part A, Polymer chemistry》2010,48(23):5322-5328
Novel polyfluorene copolymers with pendant hydroxyl groups, poly[2,7‐(9,9‐dihexylfluorene)‐2,7‐(9,9‐bis(6‐hydroxyhexyl)fluorene)‐co‐2,7‐(9,9‐dihexylfluorene)‐1,4‐phenylene] (PFP‐OH) and poly[2,7‐(9,9‐dihexylfluorene)‐2,7‐(9,9‐bis(6‐hydroxyhexyl)fluorene)‐co‐2,7‐(9,9‐dihexylfluorene)‐4,7‐(2,1,3‐benzothiadiazole)] (PFBT‐OH) were prepared. Acid‐catalyzed polycondensations of tetraethoxysilane were carried out in the presence of these polymers to obtain homogeneous hybrids. Photoluminescence spectra of these hybrids suggested the polymers were immobilized in silica matrix retaining their π‐conjugated structures. Further, hybrids of coat film were prepared utilizing perhydropolysilazane as a silica precursor. Their optical properties were examined. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献