Kitami Institute of Technology

www.kitami-it.ac.jp/
Kitami, Japan

Kitami Institute of Technology is a national university in Kitami, Hokkaido, Japan. Founded as the Kitami Junior College of Technology on 1 April 1960, it was chartered as a university on 1 April 1966. In 2004, it became part of the National University Corporation. Wikipedia.

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Kobayashi M.,Kitami Institute of Technology
International Journal of Solids and Structures | Year: 2017

In the previous paper (Kobayashi, 2017), the new crack opening criterion deduced by a micro-crack evolution equation was proposed and verified by examination of the fracture mechanisms of metallic and ceramic materials using those well-known data, i.e., fracture toughness and so forth, based on the stresses, strains and strain gradients substituted by the stress intensity factor (SIF). However, discrepancies between experimental and estimated results in A533B steel, Al2024-T4 and SiAlon cases were caused by the plastic/damage energy dissipation. In the present paper, the improved application of the crack opening criterion to be able to apply ductile materials such as A533B steel, Al2024-T4 and SiAlon by considering the plastic/damage energy dissipation based on ASTM standard E1820-01 is proposed and the plastic/damage process zone area at the crack-tip caused by the crack growth is estimated by the crack opening criterion; even though SiAlon is ceramic material, the fracture progress of A533B steel, Al2024-T4 and SiAlon are characterized by stable crack growth (ductile fracture) in the limited range of the crack extension. Moreover, significance of the theoretically estimated yielding stress and/or fracture toughness under the predicted fracture mode is pointed out to identify the phenomenological fracture mode experimentally observed by comparison of the experimental ones; the proposed criterion of micro-crack nucleation for the ductile fracture (Kobayashi, 2012) derived by the vanishing velocity condition is examined by the improved application of the crack opening criterion in the physical point of view. Also the fracture progress of an elastic-perfect plastic material is schematically interpreted by the improved application of the crack opening criterion. © 2017.


Patent
Japan Steel Works and Kitami Institute of Technology | Date: 2015-02-11

Using a device for producing nanocarbon, a fluidized bed is formed by supplying a low hydrocarbon and oxygen to a fluid catalyst, and nanocarbon and hydrogen are produced by a decomposition reaction of the low hydrocarbon accompanied by a self-combustion of the low hydrocarbon and the oxygen. The device includes: a fluidized bed reactor for containing the fluid catalyst and for causing the self-combustion thereof while being supplied with the low hydrocarbon and the oxygen; a gas supplying unit connected to the fluidized bed reactor for supplying the low hydrocarbon and the oxygen to the fluidized bed reactor; an exhaust gas path connected to the fluidized bed reactor for exhausting an exhaust gas in the fluidized bed reactor to outside; and a supplying unit connected to the fluidized bed reactor for supplying the fluid catalyst to the fluidized bed reactor.


Patent
Japan Steel Works and Kitami Institute of Technology | Date: 2014-03-19

A lower hydrocarbon and oxygen are supplied to a fluid catalyst (1) to form a fluidized bed, and nanocarbon and hydrogen are produced by a decomposition reaction of the lower hydrocarbon that accompanies self-combustion of the lower hydrocarbon and oxygen using a nanocarbon manufacturing device having a fluidized bed reactor (2) housing a fluid catalyst (1) and supplied with a lower hydrocarbon and oxygen such that the lower hydrocarbon and oxygen can self-combust, a gas feed part (5) that is connected to the fluidized bed reactor (2) and supplies lower hydrocarbon and oxygen into the fluidized bed reactor (2), a waste gas channel (8) that is connected to the fluidized bed reactor (2) and discharges the waste gas in the fluidized bed reactor (2) to the outside, and a supply part (2a) that is connected to the fluidized bed reactor (2) and supplies the fluid catalyst (1) into the fluidized bed reactor (2).


Patent
Japan Steel Works and Kitami Institute of Technology | Date: 2014-01-15

A synthetic gas and nanocarbon production method has: a light hydrocarbon decomposition step in which light hydrocarbons are decomposed to generate a hydrogen and nanocarbon; a carbon dioxide reduction step in which some of the generated nanocarbons are reacted with carbon dioxide to produce carbon monoxide; and a mixing step in which the generated hydrogen and carbon monoxide are mixed at a predetermined ratio to obtain synthetic gas. These steps enable simultaneous and easy production of nanocarbon and synthetic gas having a desired gas ratio.


Patent
Kitami Institute of Technology and Japan Steel Works | Date: 2012-05-10

Using a device for producing nanocarbon, a fluidized bed is formed by supplying a low hydrocarbon and oxygen to a fluid catalyst 1, and nanocarbon and hydrogen are produced by a decomposition reaction of the low hydrocarbon accompanied by a self-combustion of the low hydrocarbon and the oxygen, wherein the device for producing nanocarbon includes: a fluidized bed reactor 2 for containing, the fluid catalyst 1 and for causing the self-combustion of the low hydrocarbon and the oxygen while being supplied with the low hydrocarbon and the oxygen; a gas supplying unit 5 connected to the fluidized bed reactor 2 and for supplying the low hydrocarbon and the oxygen to the fluidized bed reactor 2; an exhaust gas path 8 connected to the fluidized bed reactor 2 and for exhausting an exhaust gas in the fluidized bed reactor 2 to outside; and a supplying unit 2a connected to the fluidized bed reactor 2 and for supplying the fluid catalyst 1 to the fluidized bed reactor 2.


Patent
Kitami Institute of Technology and Japan Steel Works | Date: 2012-03-09

A synthesis gas and nanocarbon production method has a lower hydrocarbon decomposition step for decomposing lower hydrocarbon to produce hydrogen and nanocarbon, a carbon dioxide reduction step for reacting a part of the nanocarbon produced with carbon dioxide to produce carbon monoxide, and a mixing step for mixing the hydrogen and carbon monoxide produced in a predetermined ratio, thereby nanocarbon and a synthesis gas having a desired gas ratio can be simultaneously produced easily.


Patent
Japan Steel Works and Kitami Institute of Technology | Date: 2016-03-23

A synthesis gas and nanocarbon production method has a lower hydrocarbon decomposition step for decomposing lower hydrocarbon to produce hydrogen and nanocarbon, a carbon dioxide reduction step for reacting a part of the nanocarbon produced with carbon dioxide to produce carbon monoxide, and a mixing step for mixing the hydrogen and carbon monoxide produced in a predetermined ratio, thereby nanocarbon and a synthesis gas having a desired gas ratio can be simultaneously produced easily.


Arai H.,Kitami Institute of Technology
Sub-Cellular Biochemistry | Year: 2014

Lipoproteins consist of lipids and apolipoproteins that have functional roles in lipid metabolism. It has been suggested that oxidation of lipoproteins by reactive oxygen species (ROS) may be involved in the inception of various dis- eases. In particular, the relationship between low-density lipoprotein (LDL) oxida- tion and atherosclerosis has been studied in great detail. The main target molecules of lipoprotein oxidation are polyunsaturated fatty acid residues of lipids and apolipoproteins. Extensive investigations have characterized oxidative modifica- tions of apolipoprotein B100 (apo B100) in LDL. Furthermore, modifications of apo B100 by oxidized lipids have been confirmed in oxidized LDL and atheroscle- rotic lesions using immunological techniques. In this chapter, characteristics and oxidation mechanisms of lipoproteins by ROS are described from in vitro and in vivo studies. Oxidative modifications of apo B100 by lipid hydroperoxides, major products of lipid peroxidation at the early stage, are principally reported. © Springer Science+Business Media Dordrecht 2014.


The solid oxide fuel cell triple combined cycle (SOFC-TCC) power generation system considered in this study is of rated power 1.4. MW, and it consists of SOFC (542. kW), a gas turbine (G/T, 550. kW), and a steam turbine (S/T, 308. kW). The relation of the frequency deviation based on the difference between supply and demand of an independent microgrid that interconnects the SOFC-TCC system and large-scale photovoltaics was investigated through numerical analysis. Because the stabilization of the load fluctuations of the SOFC and S/T required 1.8 to 2. h, control of load fluctuations occurring over periods of 2. h or less was mainly determined by the governor-free control of the G/T. Furthermore, the power characteristics (frequency) owing to cyclic fluctuations (changes occurring over a period of several minutes or less) to sustained fluctuations (changes occurring over a period exceeding 20. min) of a microgrid with large-scale photovoltaics was found to be strongly influenced by the magnitude of the inertial force of the G/T and S/T. From the analysis results, long-term supply-and-demand fluctuations, such as changes occurring seasonally and down to a period of 1. day, are mainly controlled by output adjustment of the SOFC and S/T, whereas the operation controlled by the setting of the governor-free control of the G/T and the inertial system of rotary machines is appropriate for short-term power fluctuations. © 2014 Elsevier Ltd.


Kobayashi M.,Kitami Institute of Technology
International Journal of Plasticity | Year: 2010

The localization of plastic deformation is discussed as "stationary discontinuity" characterized by a vanishing velocity of an acceleration wave derived using the author's proposed theory of ultrasonic wave velocities propagating in plastically deformed solids. To formulate the proposed theory, the elasto-plastic coupling effect was introduced to consider the elastic stiffness degradation due to the plastic deformation. The driving force of the deformation localization is caused by the yield vertex effect, which introduces a pronounced softening of the shear modulus, and geometrical softening due to double slip caused by lattice rotations. In the present paper, it is examined theoretically and experimentally that the diagonal terms of the introduced elasto-plastic coupling tensor represent a slight hardening followed by a pronounced softening of the elastic modulus induced by the point defect development caused by cross slides among dislocations at multiple slip stages similar to the yield vertex effects. The off-diagonal terms represent geometrical softening induced by lattice rotations such as texture evolution. Then, based on the coincidence of the onset strains between localization and acceleration waves of vanishing velocity, the diagrams of diffuse necking, localized necking and forming limit are analyzed by applying the proposed acoustic tensor, which is based on the generalized Christoffel tensor derived by the author, and solving cut off conditions of the quasi-longitudinal wave to determine the onset strains of deformation localization and localization modes. As a result, diagrams of diffuse necking, localized necking and forming limit were obtained. Moreover, the localization modes were determined and distinguished as the SH-mode, SV-mode, tearing mode and splitting mode. © 2009 Elsevier Ltd. All rights reserved.

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