Fukushima National College of Technology

Fukushima, Japan

Fukushima National College of Technology

Fukushima, Japan
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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.

Kasuga T.,Fukushima National College of Technology | Yakubo S.,Fukushima National College of Technology
2010 IEEE International Instrumentation and Measurement Technology Conference, I2MTC 2010 - Proceedings | Year: 2010

It is important for constructing a safe automobile society to decrease traffic accidents such as rear-end collision, crossing collision, and right turn collisions. Especially, the number of the traffic accidents can be decreased significantly if the occurrence of rear-end collision can be avoided. The purpose of this paper is to design a dependable model vehicle for rear-end collision avoidance even if an external disturbance is injected. For the purpose of our study, we paid attention to following distance, driving speed of the proceeding vehicle, and driving speed of the succeeding vehicle. We propose a rear-end collision avoidance mechanism based on redundant sensor signal processing, which is designed by combining three kind of sensing information using sensors with different operating principles such as infrared communication for transmitting driving speed of the proceeding vehicle, an ultrasonic sensor for following distance, and a magnetic sensor for driving speed of the succeeding vehicle. In this new concept, since the operating principles of these sensors are different, we consider that the possibility of multiple fault can be greatly reduced. It is shown in the experiment that a fault occurs only in one sensor when the sensors are exposed to sunlight or impulsive sound as an external disturbance. As a result, rear-end collision can be avoided. In conclusion, the use of sensors with different operating principles is valid to avoid rear-end collision. © 2010 IEEE.

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.

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.

Otake K.,Hokkaido University | Kinoshita H.,Fukushima National College of Technology | Kikuchi T.,Hokkaido University | Suzuki R.O.,Hokkaido University
Electrochimica Acta | Year: 2013

The electrochemical decomposition of CO2 gas in LiCl-Li 2O or CaCl2-CaO molten salt was studied to produce carbon. This process consists of the electrochemical reduction of the oxide, Li 2O or CaO, and the thermal reduction of CO2 gas by metallic Li or Ca. Two kinds of ZrO2 solid electrolytes were tested as an oxygen ions conductor and removed oxygen ions from the molten salts to the outside of reactor. After the electrolysis in the both salts, the aggregations of nanometer-scale amorphous carbon and rod-like graphite crystals were observed by transmission electron microscope. When 9.7% CO2-Ar mixed gas was blown into LiCl-Li2O or CaCl2-CaO molten salt, the current efficiency was evaluated to be 89.7% or 78.5%, respectively, by the exhaust gas analysis and the supplied charge. When the solid electrolyte with the better ionic conductivity was used, the current and the carbon production became larger. The rate determining step of this proposal was diffusion of oxygen ions in ZrO2 solid electrolyte. © 2013 Elsevier Ltd.

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.

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.

Takaara T.,Fukushima National College of Technology | Takaara T.,Tohoku University | Sano D.,Hokkaido University | Masago Y.,Tohoku University | Omura T.,Tohoku University
Water Research | Year: 2010

Algogenic organic matter produced by the excess growth of cyanobacteria in semi-closed water areas causes coagulation inhibition in drinking water production. In this study, hydrophilic substances of Microcystis aeruginosa, which were mainly composed of lipopolysaccharide (LPS) and RNA, were prepared, and the involvement of these cyanobacterial hydrophilic substances in coagulation inhibition was investigated. As a result, it was found that the negatively charged hydrophilic substances with a molecular weight higher than 10 kDa have a significant role in coagulation inhibition. Further fractionation of cyanobacterial hydrophilic substances revealed that surface-retained organic matter (SOM), including LPS, could exhibit a potent inhibitory effect on the coagulation using polyaluminum chloride (PACl), presumably because of the direct interaction of hydrophilic SOM with cations originated from PACl, which could impede the hydrolysis of the coagulant. © 2010 Elsevier Ltd.

Isogami S.,Fukushima National College of Technology
Materials Transactions | Year: 2016

An optimized homopolar magnetizing fixture consisting of four magnetic pole pieces was developed with the aim of achieving a focused magnetic flux on the surfaces of Nd-Fe-B alloy-based permanent magnets, and thus enhancing the magnetic flux density. In this fixture, only the transverse pieces involved coils providing the same magnetic poles in response to a pulsed current. Rectangular anisotropic and isotropic bonded magnets as well as sintered magnets, having dimensions of 6mm × 12mm × 24mm or 6mm × 12mm × 16 mm, were magnetized to multipoles using a prototype fixture in conjunction with a pulsed power source. As a result, the magnetic flux density perpendicular to the surface (Bz) was increased by 52% relative to that of conventional simple magnets containing the same volume of magnetic compound, with the front and back surfaces magnetized to opposite polarities. In addition, the Bz polarities of both the front and back sides of the magnet were determined to correspond to N-poles. The distribution pattern of Bz led us to conclude that the enhanced Bz and the equal polarity on both sides can both be attributed to the cusp field resulting from the flux generated by the transverse coils of the magnetizing fixture. © 2016 The Japan Institute of Metals and Materials.

Baba K.,Fukushima National College of Technology
Differential Geometry and its Application | Year: 2015

We list up all the possible local orbit types of hyperbolic or elliptic orbits for the isotropy representations of semisimple pseudo-Riemannian symmetric spaces. Our method to determine the local orbit types is based on the theory of restricted root systems and Satake diagrams associated with the spaces. © 2015 Elsevier B.V.

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