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991.
992.
The yield stress of polymethylmethacrylate (PMMA) composites filled with ultrafine SiO2 particles was measured as a function of the draw temperature, rate of strain and filler content. The yield stress of the composites increased with increasing filler content and decreasing filler size. The tensile yield stress was found to be reducible with regard to draw temperature, rate of strain and filler content. At a given filler content, a master curve was obtained for the yield stress plotted versus the logarithm of the strain rate. The Arrhenius plot of the shift factors (a
T
) used to produce the strain rate-temperature master curve formed a single curve for all sizes and loadings of the filler. The master curves obtained for different loadings of a filler of given size could be further reduced into a master-master curve by shifting them along the axis of strain rate, with the logarithm of the second shift factors (loga
c
) proportional to the 4/5th power of the filler volume fraction (V
f
). The proportionality constant and the exponent represent the extent of the filler reinforcing effect in the polymer. These values were found to be correlated with the critical surface tension of the polymers. 相似文献
993.
T. Inoue S. Ando T. Aoki H. Arikawa S. Ezure K. Harada T. Hayamizu T. Ishikawa M. Itoh K. Kato H. Kawamura A. Uchiyama T. Aoki K. Asahi T. Furukawa A. Hatakeyama K. Hatanaka K. Imai T. Murakami H. S. Nataraj T. Sato Y. Shimizu T. Wakasa H. P. Yoshida A. Yoshimi Y. Sakemi 《Hyperfine Interactions》2015,231(1-3):157-162
994.
Keitarou Ishikawa 《Applied mathematics and computation》2009,211(1):45-53
This paper shows some elementary facts on simple games with respect to blockability relations. It is verified in this paper that fundamental concepts on simple games as null players, dictators, veto players, and so on can be expressed in terms of blockability relations. More, some new concepts as “conflict-free” and so on, are introduced from the viewpoint of blockability relations into the framework of simple games. 相似文献
995.
Shigeaki Yamazaki Akihiko Takegawa Yoshiro Kaneko Jun-ichi Kadokawa Masaki Yamagata Masashi Ishikawa 《Electrochemistry communications》2009,11(1):68-70
A novel acidic cellulose–chitin hybrid gel electrolyte including binary ionic liquids (ILs) with an aqueous H2SO4 solution was prepared for an electric double layer capacitor (EDLC). Its electrochemical characteristics were investigated by galvanostatic charge–discharge measurements. The test cell with a hybrid gel electrolyte shows a specific capacitance of 162 F g?1 at room temperature, which is higher than that for a cell with an H2SO4 electrolyte, 155 F g?1. This hybrid gel electrolyte exhibits excellent high-rate discharge capability in a wide range of current densities as well as an aqueous H2SO4 solution. The discharge capacitance of the test cell can retain over 80% of its initial value in 100,000 cycles even at a high current density of 5000 mA g?1. 相似文献
996.
Juan C. Delgado Yasuyuki Ishikawa Ronald G. Selsby 《Photochemistry and photobiology》2009,85(6):1286-1298
The ionization potential (IP) and electron affinity (EA) of the isolated single dye molecule and a hypothetical isolated J-aggregated dimer are calculated as an energy difference between separately minimized ground and ionized states. Three quantum methods are employed: density functional theory (DFT) Gaussian03 B3LYP/6-311G** (++G**); DFT using Dmol3 ; and a modification of CNDO/S, called CNDO/S-Δζ, which is developed for rapid calculation of the IP and EA. Results indicate that for the monomer, 1,1'-dimethyl-2,2'carbocyanine chloride, the vertical IP and EA are 6.2 ± 0.1 and 1.90 ± 0.05 eV, respectively. This is consistent with the threshold IP and EA predicted by the Yianoulis and Nelson "Statistical Model" of spectral sensitization. For the isolated J-aggregated dimer, whose configuration is consistent with being adsorbed on a dielectric substrate, the calculations predict a value of 5.2 ± 0.2 and 2.35 ± 0.05 eV for the IP and EA, respectively. Significant charge density is removed from the halide anion in the ionization process. The HOMO of the dye molecule is an MO associated with the halide anion. Calculation of the isolated entities is a necessary preliminary step in the study of the IP and EA of the adsorbed dye monomer and aggregate. 相似文献
997.
Y. Yasuoka T. Ishikawa S. Tokonami H. Takahashi A. Sorimachi M. Shinogi 《Journal of Radioanalytical and Nuclear Chemistry》2009,279(3):885-891
Room experiments were conducted to investigate the effects of an air cleaner on radon mitigation. Radon concentration, equilibrium
equivalent radon concentration and unattached fraction were measured during the experiments. Two types of filtration were
tested using the air cleaner which has a high efficiency particulate air filter (HEPA-filter) and a deodorizing activated
carbon (carbon-filter). One is the filtration with the HEPA-filter plus carbon-filter and the other is the filtration with
only the HEPA-filter. The effective doses from radon progeny were significantly decreased. Both filtration methods were effective
for the mitigation of effective dose due to radon progeny. 相似文献
998.
T. Ishikawa Y. Yasuoka S. Tokonami H. Takahashi H. Suda 《Journal of Radioanalytical and Nuclear Chemistry》2009,279(3):719-724
Water originated from groundwater systems can have relatively high concentration of radon. In many situations, radon is released
from the water and mixes with the indoor air. In the present study, laboratory experiments were conducted to characterize
the airborne radon released by showering and the use of a washing machine. The followings were discussed: (1) a comparison
between the loss of waterborne radon and the increase of airborne radon, (2) time-related changes in airborne radon after
the water use, (3) changes in the equilibrium factor, and (4) the relationship between radon concentration and the distance
from the source of radon release. 相似文献
999.
M. Yao K. Nagaya H. Iwayama H. Fukuzawa K. Ueda M. Nagasono T. Ishikawa 《The European physical journal. Special topics》2011,196(1):175-180
Unlike metallic elements, rare-gas atoms remain non-metallic even if they are condensed. However, once rare-gas clusters are
irradiated by extreme ultraviolet free electron laser (EUV-FEL) pulses with slightly higher energy than their ionization potential,
they exhibit metallic-like behaviors because the ionization takes place sequentially within the clusters owing to the huge
valence electron ionization cross section in the EUV regime. In this work Ar and Xe clusters were produced by pulsed supersonic
jets, and the cluster beams were crossed synchronously with focused EUV-FEL beams ejected from the SCSS test accelerator in
Japan. We measured time-of-flight (TOF) mass spectra and kinetic energy distribution (KED) of daughter ions produced via Coulomb
explosion by using three dimensional (3D) momentum imaging spectrometer. The metallic-like nature is evidenced not only by
widely spread charge distributions within the cluster but also by enhanced positive surface charges surrounded by quasi-free
electron clouds. 相似文献
1000.
M. Inui Y. Kajihara K. Matsuda S. Hosokawa K. Tamura M. Yao Y. Tsuchiya D. Ishikawa S. Tsutsui A. Q. R. Baron 《The European physical journal. Special topics》2011,196(1):167-174
Liquid As2Se3 undergoes the semiconductor-metal transition with increasing temperature when pressure is applied to avoid evaporation of
the liquid. To investigate the atomic dynamics of liquid As2Se3, we have carried out inelastic x-ray scattering experiments of this system at 1073 K and 6 MPa and obtained the dynamic structure
factor S(Q,E), from approximately 1.6 nm−1 to 11 nm−1, where Q and E are momentum and energy transfer, respectively. The excitation energy in the semiconducting state at 1073 K disperses as
fast as the ultrasonic sound velocity at Q < 2.5 nm−1 but at Q > 2.9 nm−1 it disperses approximately 1.8 times faster. We analyzed S(Q,E) at 1073 K using a simple viscoelastic model and discussed Q dependence of the propagation of the acoustic mode. 相似文献