Sophia University

About: Sophia University is a education organization based out in Tokyo, Japan. It is known for research contribution in the topics: Nonlinear system & Catalysis. The organization has 4986 authors who have published 7657 publications receiving 106567 citations. The organization is also known as: Jōchi Daigaku.

Multi-reflection time-of-flight mass spectrograph for short-lived radioactive ions

Abstract: RIKEN’s new RI-Beam Factory (RIBF) will provide unprecedented access to neutron-rich nuclei of importance to r-process nucleosynthesis. We are constructing an advanced multi-reflection time-of-flight mass spectrograph to perform precision mass measurements of these nuclei. We discuss the device and compare its performance to that of the well-known Penning trap mass spectrometer.

The Role of Personal Standards in Clinically Significant Perfectionism. A Person-Oriented Approach to the Study of Patterns of Perfectionism

Abstract: Clinically significant perfectionism is defined as patterns of perfectionism which are over-represented in clinical samples and under-represented in non-clinical samples. The present study contrasted two hypotheses about what characterizes clinically significant perfectionism: the two-factor theory and perfectionism/acceptance theory. First, a person-oriented approach by means of cluster analysis was used to identify typical patterns of perfectionism. These clusters were then cross-tabulated with two clinical samples (patients with social phobia and patients with panic disorder) and a non-clinical sample. The results showed that patterns of clinically significant perfectionism combined high Concern over Mistakes (CM) and Doubts about Action (DA) with high Personal Standards (PS) (and to a lesser extent also high Organization)––which is consistent with perfectionism/acceptance theory, but at odds with the two-factor theory. The results illustrate the value of a person-oriented methodological approach as a complement to the traditional variable-oriented approach.

Positive binding energy of a biexciton confined in a localization center formed in a single InxGa1-xN/GaN quantum disk

Abstract: We report microphotoluminescence spectroscopy performed on individual and ensemble InGaN/GaN quantum disks (Q-disks). The typical spectrum of a single Q-disk exhibited the contribution of localization centers (LCs) formed in the InGaN active layer of the Q-disks, characterized by sharp lines appearing on the low energy side of the spectra. In addition, a broader emission peak identified as the luminescence of the quasi-two-dimensional (2D) InGaN active layer surrounding the LCs appears systematically at higher energy. Time-resolved photoluminescence experiment performed on single Q-disks exhibited the excitonic transfer, from the 2D InGaN active layer to LCs, at the submicroscopic scale. Excitation power dependence studies and linear polarization analysis allowed us to identify a biexciton complex confined in a LC in a single Q-disk with a surprising positive binding energy of 13 meV. The absence of screening effect by increasing the excitation power density and the fast excitonic radiative lifetime of a few hundred picoseconds that we measured on several individual Q-disks indicate that the absence of internal electric field in the structure can explain the observed positive biexciton binding energy.