Fukui University of Technology

About: Fukui University of Technology is a education organization based out in Fukui-shi, Japan. It is known for research contribution in the topics: Differential scanning calorimetry & Polymerization. The organization has 485 authors who have published 1263 publications receiving 22336 citations.

Photo- and electroactive amorphous molecular materials—molecular design, syntheses, reactions, properties, and applications

Abstract: A new field of organic materials science that deals with amorphous molecular glasses has been opened up. In addition, amorphous molecular materials have constituted a new class of functional organic materials for use in various applications. This article is focused on the recent progress of studies on photo- and electroactive amorphous molecular materials, highlighting photochromic amorphous molecular materials, amorphous molecular resists, and amorphous molecular materials for use in devices such as organic EL devices. The molecular design concepts, syntheses, reactions, molecular and solid-state properties, functions, and device fabrication and performance are described.

Observations and implications of the ultrahigh-energy cosmic rays

Abstract: The authors define ``ultrahigh-energy cosmic rays'' (UHECRs) as those cosmic rays with energies above ${10}^{18}\mathrm{eV}.$ It had been anticipated that there would be a cutoff in the energy spectrum of primary cosmic rays around $6\ifmmode\times\else\texttimes\fi{}{10}^{19}\mathrm{eV}$ induced by the interaction of the particles with the 2.7-K primordial photons. However, recent experimental data have established that particles exist with energies greatly exceeding this. It follows that the sources of such particles are probably nearby, on a cosmological scale. However, although the trajectories of such energetic particles through the galactic and intergalactic magnetic fields may be nearly rectilinear, no astronomical sources have as yet been identified. This is the enigma of the highest-energy cosmic rays. The paper reviews the history of research in this energy regime and critically assesses the observational results on the energy spectrum, arrival directions, and composition of the primary cosmic rays based on observations made by six experiments. The detection methods currently available are described. Special techniques have been developed as particles of ${10}^{20}\mathrm{eV}$ or higher occur at a rate of only about 1 per ${\mathrm{km}}^{2}$ per century. Errors in measurement are given particular attention. The authors also review the theoretical predictions for a number of candidate sources of cosmic rays beyond the predicted cutoff. Finally, the four major projects planned to address the question of the origin of UHECRs are briefly described.

Small-Scale Anisotropy of Cosmic Rays above 1019 eV Observed with the Akeno Giant Air Shower Array

Abstract: With the Akeno Giant Air Shower Array, 581 cosmic rays above 1019 eV, 47 above 4 ) 1019 eV, and seven above 1020 eV were observed until 1998 August. The arrival direction distribution of these extremely high energy cosmic rays has been studied. While no signi—cant large-scale anisotropy is found on the celestial sphere, some interesting clusters of cosmic rays are observed. Above 4 ) 1019 eV, there are one triplet and three doublets within a separation angle of and the probability of observing 2i.5, these clusters by a chance coincidence under an isotropic distribution is smaller than 1%. The triplet is especially observed against expected 0.05 events. The distribution expected from the dark cos (h GC ) matter halo model —ts the data as well as an isotropic distribution above 2 ) 1019 and 4 ) 1019 eV, but the —t with the dark matter halo model is poorer than the isotropic distribution above 1019 eV. The arrival direction distribution of seven 1020 eV cosmic rays is consistent with that of lower energy cosmic rays and is uniform. Three of the seven are members of doublets above about 4 ) 1019 eV. Subject headings: cosmic raysgalaxies: generalGalaxy: halolarge-scale structure of universe