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Osada M.,Ichinoseki National College of Technology | Kikuta K.,Ichinoseki National College of Technology | Yoshida K.,Ichinoseki National College of Technology | Totani K.,Ichinoseki National College of Technology | And 2 more authors.
Green Chemistry | Year: 2013

Non-catalytic synthesis of 2-acetamido-2,3-dideoxy-d-erythro-hex-2- enofuranose (Chromogen I) and 3-acetamido-5-(1′,2′-dihydroxyethyl) furan (Chromogen III) from N-acetyl-d-glucosamine (GlcNAc) was achieved, with the highest yields of 23.0% and 23.1%, respectively, in high-temperature water at 120-220 °C and 25 MPa with a reaction time of 7-39 s. This journal is © 2013 The Royal Society of Chemistry. Source


Arai M.,Czech Technical University | Arai M.,Fukushima National College of Technology | Kawai S.,Sungkyunkwan University | Okada N.,University of Alabama
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2014

We investigate a novel scenario of cosmological inflation in a gauged B - L extended minimal supersymmetric Standard Model with R-symmetry. We use a noncanonical Kähler potential and a superpotential, both preserving the R-symmetry to construct a model of slow-roll inflation. The model is controlled by two real parameters: the nonminimal coupling ξ that originates from the Kähler potential, and the breaking scale v of the U(1)B -L symmetry. We compute the spectrum of the cosmological microwave background radiation and show that the prediction of the model fits well the recent Planck satellite observation for a wide range of the parameter space. We also find that the typical reheating temperature of the model is low enough to avoid the gravitino problem but nevertheless allows sufficient production of the baryon asymmetry if we take into account the effect of resonance enhancement. The model is free from cosmic strings that impose stringent constraints on generic U(1)B -L based scenarios, as in our scenario the U(1)B -L symmetry is broken from the onset. © 2014 The Authors. Source


Arai M.,Fukushima National College of Technology | Kawai S.,Institute for the Early Universe | Kawai S.,Sungkyunkwan University | Okada N.,University of Alabama
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

We investigate a scenario of cosmological inflation realized along a flat direction of the minimal seesaw model embedded in supergravity with a noncanonical R-parity violating Kähler potential. It is shown that with appropriate seesaw parameters the model is consistent with the present observation of the cosmological microwave background as well as with the neutrino oscillation data. It is also shown that the baryon asymmetry of the Universe can be generated through leptogenesis. The model favors supersymmetry breaking with the gravitino as the lightest superparticle, and thus indicates the gravitino dark matter scenario. An interesting feature of this model is that the seesaw parameters are constrained by the cosmological microwave background spectra. The 2-σ constraints from the 9-year WMAP data yield a mild lower bound on the seesaw mass scale a TeV. We expect that the observation by the Planck satellite will soon provide more stringent constraints. The phenomenological and cosmological implications of the R-parity violation are also discussed. © 2013 American Physical Society. Source


Michikami T.,Fukushima National College of Technology | Michikami T.,Open University Milton Keynes | Nakamura A.M.,Kobe University | Hirata N.,University of Aizu
Icarus | Year: 2010

Laboratory impact experiments have found that the shape of fragments over a broad size range is distributed around the mean value of the axial ratio 2:√2:1, which is independent of a wide range of experimental conditions. We report the shape statistics of boulders with size of 0.1-30 m on the surface of Asteroid 25143 Itokawa based on high-resolution images obtained by the Hayabusa spacecraft in order to investigate whether their shape distribution is similar to the distribution obtained for fragments (smaller than 0.1 m) in laboratory impact experiments. We also investigated the shapes of boulders with size of 0.1-150 m on Asteroid 433 Eros using a few arbitrary selected images by the NEAR spacecraft, in order to compare those with the shapes on Asteroid Itokawa. In addition, the shapes of small- and fast-rotating asteroids (diameter <200 m and rotation period <1 h), which are natural fragments from past impact events among asteroids, were inferred from archived light curve data taken by ground-based telescopes. The results show that the shape distributions of laboratory fragments are similar to those of the boulders on Eros and of the small- and fast-rotating asteroids, but are different from those on Itokawa. However, we propose that the apparent difference between the boulders of Itokawa and the laboratory fragments is due to the migration of boulders. Therefore, we suggest that the shape distributions of the boulders ranging from 0.1 to 150 m in size and the small- and fast-rotating asteroids are similar to those obtained for the fragments generated in laboratory impact experiments. © 2009 Elsevier Inc. All rights reserved. Source


Arai M.,Yamagata University | Baba K.,Fukushima National College of Technology
Journal of High Energy Physics | Year: 2015

We construct N = 2 supersymmetric nonlinear sigma models on the cotangent bundles over the non-compact exceptional Hermitian symmetric spaces M = E6(-14)/SO(10)×U(1) and E7(−25)/E6× U(1). In order to construct them we use the projective superspace formalism which is an N = 2 off-shell superfield formulation in four-dimensional space-time. This formalism allows us to obtain the explicit expression of N = 2 supersymmetric nonlinear sigma models on the cotangent bundles over any Hermitian symmetric spaces in terms of the N = 1 superfields, once the Kähler potentials of the base manifolds are obtained. We derive the N = 1 supersymmetric nonlinear sigma models on the Kähler manifolds M. Then we extend them into the N = 2 supersymmetric models with the use of the result in arXiv:1211.1537 developed in the projective superspace formalism. The resultant models are the N = 2 supersymmetric nonlinear sigma models on the cotangent bundles over the Hermitian symmetric spaces M. In this work we complete constructing the cotangent bundles over all the compact and non-compact Hermitian symmetric spaces. © 2015, SISSA, Trieste, Italy. Source

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