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Koganei, Japan

Tokyo Gakugei University or Gakudai , for short, is a national university in Koganei, Tokyo. While its history may be traced to 1873, it was formally chartered as a university in 1949 through the merging of four teacher-training institutions.In 1966, the Graduate School of Tokyo Gakugei University was established, and since 1996 it has offered Doctoral degrees in the education field as part of a coalition of educational institutions that include Chiba University, Saitama University, and Yokohama National University.In recent years, Tokyo Gakugei University has developed programs to better accommodate professional school teachers, including evening and short-term courses. The university also houses a number of national research centres in education-related fields. In addition to its Koganei campus, it also maintains a number of attached public schools offering curricula in elementary, secondary, and special education at various locations in the greater Tokyo area. The university has a strong reputation in education-related fields, playing a national role in the development of educational policy and innovations in teacher education. Wikipedia.

Yamada M.,Tokyo Gakugei University | Akasaka T.,University of Tsukuba | Nagase S.,Kyoto University
Chemical Reviews | Year: 2013

Carbenes are unquestionably powerful intermediates to functionalize fullerenes. Various carbene precursors are useful for reactions. The availability of widely diverse carbene precursors enriches the fullerene chemistry. Both electrophilic and nucleophilic carbenes are applicable reagents, giving the corresponding fullerene derivatives. The reaction mechanisms depend on the precursors and reaction conditions applied. A typical carbene reaction involves addition to a π bond of olefins, which is also the case for a π bond of fullerenes. It is also important to note that carbenes exhibit diverse reactivity. Singlet carbenes possess both electrophilic and nucleophilic character, whereas triplet carbenes show diradical reactivity. Dihalocarbene, because it is among the simplest and most representative carbene species, is widely used in synthetic chemistry. Diazo compounds are useful carbene transfer reagents to fullerenes. Source

Hasegawa H.,Tokyo Gakugei University
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2010

We have studied finite N -body D -dimensional nonextensive ideal gases and harmonic oscillators, by using the maximum-entropy methods with the q and normal averages (q: the entropic index). The validity range, specific heat and Tsallis entropy obtained by the two average methods are compared. Validity ranges of the q - and normal averages are 0 q L, respectively, where qU =1+ (ηDN ) -1, qL =1- ( ηDN+1 ) -1 and η=1/2 (η=1) for ideal gases (harmonic oscillators). The energy and specific heat in the q and normal averages coincide with those in the Boltzmann-Gibbs statistics, although this coincidence does not hold for the fluctuation of energy. The Tsallis entropy for N | q-1 | 1 obtained by the q average is quite different from that derived by the normal average, despite a fairly good agreement of the two results for | q-1 | 1. It has been pointed out that first-principles approaches previously proposed in the superstatistics yield additive N -body entropy (S (N) =N S (1)) which is in contrast with the nonadditive Tsallis entropy. © 2010 The American Physical Society. Source

Hasegawa H.,Tokyo Gakugei University
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2011

We have studied dynamical responses and the Jarzynski equality (JE) of classical open systems described by the generalized Caldeira-Leggett model with the nonlocal system-bath coupling. In the derived non-Markovian Langevin equation, the nonlinear nonlocal dissipative term and state-dependent diffusion term yielding multiplicative colored noise satisfy the fluctuation-dissipation relation. Simulation results for harmonic oscillator systems have shown the following: (a) averaged responses of the system 〈x〉 to applied sinusoidal and step forces significantly depend on model parameters of magnitudes of additive and multiplicative noises and the relaxation time of colored noise, although stationary marginal probability distribution functions are independent of them, (b) a combined effect of nonlinear dissipation and multiplicative colored noise induces enhanced fluctuations 〈[x- x〈x〉]2〉 for an applied sinusoidal force, and (c) the JE holds for an applied ramp force independently of the model parameters with a work distribution function which is (symmetric) Gaussian and (asymmetric) non-Gaussian for additive and multiplicative noises, respectively. It has been shown that the non-Markovian Langevin equation in the local and overdamped limits is quite different from the widely adopted, phenomenological Markovian Langevin equation subjected to additive and multiplicative noises. © 2011 American Physical Society. Source

Hasegawa H.,Tokyo Gakugei University
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2012

Specific heats of quantum systems with symmetric and asymmetric double-well potentials have been calculated. In numerical calculations of their specific heats, we have adopted the combined method, which takes into account not only eigenvalues of εn for 0≤n≤Nm obtained by the energy-matrix diagonalization but also their extrapolated ones for N m+1≤n<∞ (Nm=20 or 30). Calculated specific heats are shown to be rather different from counterparts of a harmonic oscillator. In particular, specific heats of symmetric double-well systems at very low temperatures have the Schottky-type anomaly, which is rooted to a small energy gap in low-lying two-level eigenstates induced by a tunneling through the potential barrier. The Schottky-type anomaly is removed when an asymmetry is introduced into the double-well potential. It has been pointed out that the specific-heat calculation of a double-well system reported by Feranchuk, Ulyanenkov, and Kuz'min is misleading because the zeroth-order operator method they adopted neglects crucially important off-diagonal contributions. © 2012 American Physical Society. Source

Hasegawa H.,Tokyo Gakugei University
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2011

We have studied the properties of a classical NS-body system coupled to a bath containing NB-body harmonic oscillators, employing an (NS+NB) model that is different from most of the existing models with NS=1. We have performed simulations for N S-oscillator systems, solving 2(NS+NB) first-order differential equations with NS≃1-10 and N B≃10-1000, in order to calculate the time-dependent energy exchange between the system and the bath. The calculated energy in the system rapidly changes while its envelope has a much slower time dependence. Detailed calculations of the stationary energy distribution of the system f S(u) (u: an energy per particle in the system) have shown that its properties are mainly determined by NS but weakly depend on N B. The calculated fS(u) is analyzed with the use of the Γ and q-Γ distributions: the latter is derived with the superstatistical approach (SSA) and microcanonical approach (MCA) to the nonextensive statistics, where q stands for the entropic index. Based on analyses of our simulation results, a critical comparison is made between the SSA and MCA. Simulations have been performed also for the NS-body ideal-gas system. The effect of the coupling between oscillators in the bath has been examined by additional (NS+NB) models that include baths consisting of coupled linear chains with periodic and fixed-end boundary conditions. © 2011 American Physical Society. Source

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