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41.
Using p,p'-dimethoxydiphenyldiazomethane (DMDM) as initiator, the polymerization of methyl methacrylate (MMA) in benzene or in bulk was carried out. The initial rate of polymerization, Rp, was found to be expressed by the following equation: Rp = k[DMDM]0.53 [MMA]0.84 The polymerization was confirmed to proceed by a radical mechanism. The over-all activation energy for the polymerization in benzene was calculated as 19.3 kcal/mole. The rate of thermal decomposition of DMDM was also measured in benzene and the rate equation was obtained as follows: kd (sec?1) = 1.0 × 1015 exp (?29.1 kcal/RT) (for 50-80°C) Explanations of these observations are discussed in connection with those of the preceding papers. 相似文献
42.
Several polyurethanes based on bis-(p-oxymethylphenyl) terephthalate (BOPT) were synthesized and studied with respect to some of their thermal properties. BOPT exhibits a mesomorphic phase at 252–264°C. Polymerization was carried out by equimolar reaction with hexamethyl-ene diisocyanate (HDI), 4,4-dicyclohexylmethane diisocyanate (H12MDI) α,α'-diisocyanate-1,3-dimethylcyclohexane (H6 XDI), 4,4′-diphenylmeth-ane diisocyanate (MDI), 2,4-tolylene diisocyanate (TDI), and phenylene diisocyanate (PDI). It became clear that polyurethanes obtained from BOPT with HDI, H12MDI, H6XDI, and TDI have mesomorphic phases at 243–291, 214–250, 172–229, and 180–234°C, respectively, as determined by DSC and polarized microscopy, and that all polyurethanes are crystalline as evidenced by x-ray diffraction. 相似文献
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44.
Yoshiki K Kanamaru R Ryosuke K Hashimoto M Hashimoto N Araki T 《Optics letters》2007,32(12):1680-1682
We developed a compact polarization-mode converter for microscopy to control three-dimensional polarization at the focus. The converter consisted of two homogeneously aligned liquid-crystal spatial light modulators with eight independently controllable electrodes (segments), and a quarter-waveplate. The converter converted a linearly polarized beam to three polarization modes: two orthogonal linear polarizations and a pseudo-radial polarization. We applied the converter to second-harmonic-generation microscopy and demonstrated the detection of three-dimensional molecular orientation. 相似文献
45.
Takehisa Dewa Ayumi Sumino Natsuko Watanabe Tomoyasu Noji Mamoru Nango 《Research on Chemical Intermediates》2014,40(9):3243-3256
Appropriate experimental platforms are required to clarify the structure–function relationships of membrane protein assemblies. In photosynthetic bacteria, light-harvesting complex 2 and light-harvesting/reaction center core complex play key roles in capturing and transferring light energy and facilitating subsequent charge separation. These photosynthetic apparatuses form a supramolecular assembly in the photosynthetic membrane. However, the mechanism through which this assembly influences the efficiency of energy conversion remains to be clarified. We review our recent studies that were conducted to evaluate the structure–function relationship of the supramolecular assembly of photosynthetic antenna complexes in various lipid bilayer systems, as well as the construction of novel systems of planar lipid membranes for use as experimental platforms. 相似文献
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Road signs must provide a conspicuous signal to a wide variety of drivers over a broad range of environmental and geometric
conditions. Recently, there are an increasing number of applications in which light emitting diodes (LEDs) are used as the
light source, including critical transportation signaling. In the presence of fog, the resulting visual signal is disturbed
due to light scattering by airborne water droplets. By measuring LED brightness with human spectral sensitivity in various
densities and various droplet sizes (10, 30, 50, and 100 μm), it is understood that the particle size distribution (fog droplet
size) and density of fog does affect visibility in fog. The colored LEDs that contain a yellow component had high brightness
evaluation, blue component had low brightness evaluation in all densities and different droplet sizes. The result in this
paper can contribute to air and land traffic safety and the prevention of accidents. 相似文献
49.
Hashi K Shimizu T Goto A Kiyoshi T Matsumoto S Wada H Fujito T Hasegawa K Yoshikawa M Miki T Ito S Hamada M Hayashi S 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2002,156(2):318-321
We have developed a 920-MHz NMR system and performed the proton NMR measurement of H(2)O and ethylbenzene using the superconducting magnet operating at 21.6 T (920 MHz for proton), which is the highest field produced by a superconducting NMR magnet in the persistent mode. From the NMR measurements, it is verified that both homogeneity and stability of the magnet have a specification sufficient for a high resolution NMR. 相似文献
50.
In this paper we explore the relation between information patterns and Nash Equilibria in extensive games. By information we mean what players know about moves made by others, as well as by chance. For the most part we confine ourselves to pure strategies. But in Section 2 behavioral strategies are also examined. It turns out that they can be modeled as pure strategies of an appropriately enlarged game. Our results, applied to the enlarged game, can then be reinterpreted in terms of the behavioral strategies of the original game. 相似文献