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991.
992.
993.
Yuping Yuan Tsuyoshi Michinobu Minoru Ashizawa Takehiko Mori 《Journal of polymer science. Part A, Polymer chemistry》2011,49(4):1013-1020
The alkyne moieties of poly(3‐hexylthienyleneethynylene) were reacted with tetracyanoethylene or 7,7,8,8‐tetracyanoquinodimethane by microwave irradiation to produce donor–acceptor chromophores in the polymer main chain. The resulting polymers were fully characterized by GPC, 1H NMR, and IR spectroscopies, and elemental analyses. They were both thermally and chemically stable, as revealed by thermogravimetric analyses and ESR measurements. UV–vis‐NIR spectroscopy revealed charge‐transfer bands in the low‐energy region, and electrochemistry confirmed the narrower band gaps with the elevated HOMO and lower LUMO levels relative to the precursor polymer. To take advantage of these postfunctionalization methods, p‐type doping of the polymers with I2 was attempted. Room temperature conductivities of the postfunctionalized polymers reached 4.5 × 10?5 S cm?1, which was about 10 times greater than that of the precursor polymer. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
994.
To separate MA(Am,Cm) and some fission product elements(FPs) such as Tc,Pd,Cs and Sr from high level liquid waste(HLLW) systematically,we have been studying an advanced aqueous partitioning process,which uses selective adsorption as the separation method.For this process,we prepared several novel adsorbents which were immobilized in a porous silica/polymer composite support(SiO 2-P).Adsorption and separation behavior of various elements was studied experimentally in detail.Small scale separation tests using simulated HLLW solutions were carried out.Pd(II) was strongly adsorbed by the AR-01 anion exchanger and effectively eluted off by using thiourea.Successful separation of Pd(II) from simulated HLLW was achieved.Tc(VII) also exhibited strong adsorption on AR-01 and could be eluted off by using U(IV) as a reductive eluent.Am(III) presented significantly high adsorbability and selectivity onto R-BTP/SiO 2-P adsorbents over various FPs including Ln(III).The R-BTP adsorbents were fairly stable in 3 M HNO 3,but instable against-irradiation-3M HNO 3.An advanced partitioning process consisting of three separation columns for the target elements separation from HLLW was proposed and the obtained experiment results indicated that the proposed process is essentially feasible. 相似文献
995.
Tomoya NobutaNorihiro Tada Kasumi HattoriShin-ichi Hirashima Tsuyoshi MiuraAkichika Itoh 《Tetrahedron letters》2011,52(8):875-877
We report a useful method for facile aerobic photo-oxidative synthesis of α-diketones from alkynes with MgBr2·OEt2. This procedure provides a practical synthetic method of α-diketones using easily handled bromine sources, harmless visible light, and molecular oxygen as terminal oxidant. 相似文献
996.
997.
Inside Back Cover: Fast and Efficient Oxidative Cycloreversion Reaction of a π‐Extended Photochromic Terarylene (Chem. Eur. J. 29/2016)
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998.
The existence of a local-in-time unique solution and loss of smoothness of a full Magneto-Hydro-Dynamics (MHD) system are considered for periodic initial data. The result is proven using Fujita–Kato’s method in based (for the Fourier coefficients) functional spaces enabling us to easily estimate nonlinear terms in the system as well as solutions to Maxwell’s equations. A loss of smoothness result is shown for the velocity and magnetic field. It comes from the damped-wave operator which does not have any smoothing effect. 相似文献
999.
1000.
Tsuyoshi Kajimoto Nobuhiro Shigyo Kenji Ishibashi Hiroyuki Arakawa Robert C. Haight Nikolaos Fotiades 《Radiation measurements》2012,47(8):596-608
Many benchmark data are required for the improvement of theoretical model implemented in a Monte Carlo code for particle transport. To acquire the benchmark data, we measured energy spectra of protons emitted from graphite, aluminum, and iron targets bombarded with continuous-energy neutrons, which enable simultaneous measurements at the incident energies from 100 to 600 MeV at a time. The neutron flux incident on the target was measured with a 238U fission ionization chamber. Protons emitted from the target were measured with three ΔE–E detectors consisting of a thin NE102A scintillator and a thick NE213 liquid scintillator. In the analysis, the pulse shape discrimination of the NE213 scintillator enable us to distinguish events for a charged particle stopping in the scintillator from events for a charged particle penetrating the scintillator. Experimental results were compared with calculations by the PHITS code coupled with the JENDL-HE file, the Bertini model implemented in the PHITS code, and the PEANUT model in the FLUKA code. 相似文献