Inward Migration of Glass‐Modifier Cations During Heat Treatment Under an N2 Atmosphere

An Na⁺/Ca²⁺‐deficient layer is observed to form on the glass surface region up to a depth of hundreds of nanometers when a soda‐lime‐silicate glass is heat treated under an N₂ atmosphere near its glass‐transition temperature. The measurements were performed using X‐ray photoelectron spectroscopy with C₆₀‐ion sputtering (C₆₀‐XPS) and dynamic secondary‐ion mass spectrometry (D‐SIMS) with consideration of the mass and charge balances. The increase in the amount of hydrogen is substantially less than the decrease in the total charge due to the loss of modifier cations in the Na⁺/Ca²⁺‐deficient layer; furthermore, the oxygen concentration in this layer is lower than the bulk value, suggesting that the silanol groups in the surface layer of the glass are dehydrated. A high‐concentration layer of Ca²⁺ is also confirmed in the dehydration layer of the glass heat treated under an N₂ atmosphere, suggesting that Na⁺ and Ca²⁺ ions migrate inward into the glass via an ion‐exchange reaction with protons, which migrate toward the surface from the bulk. We also confirmed that a thicker Na⁺/Ca²⁺‐deficient layer is formed on glass surfaces with higher water content. Our results suggest that the dehydration of the silanol groups is the driving force of the inward migration of Na⁺ and Ca²⁺ ions.     

Synthesis of sulfonated polynaphthalene,polyanthracene, and polypyrene as strong solid acids via oxidative coupling polymerization

Oxidative coupling polymerization of naphthalene, anthracene, and pyrene with FeCl₃ in nitrobenzene under nitrogen gave polynaphthalene (PNP), polyanthracene (PAT), and polypyrene (PPR) in good yields, respectively. PNP, PAT, and PPR were transformed into sulfonated PNP (S‐PNP), S‐PAT, and S‐PPR by the treatment with chlorosulfonic acid in dichloromethane at 25°C for 24 h under nitrogen, respectively. The activities of S‐PPR were higher than those of S‐PNP and S‐PAT. For the hydrolysis of cyclohexyl acetate and oleyl acetate in water, activities of S‐PPR, S‐PAT, and S‐PNP were considerably higher than those of the other conventional solid acids. Rate constants of S‐PPR were 2.8 and 11.7 times larger than those of the sulfonated condensed polynuclear aromatic (S‐COPNA(PR)) resin (PR = pyrene) for the hydrolysis of cyclohexyl acetate and oleyl acetate, respectively. S‐PPR, S‐PAT, and S‐PNP were reused without significant loss of activities. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

The Contribution of Geraniol Metabolism to the Citrus Flavour of Beer: Synergy of Geraniol and β‐Citronellol Under Coexistence with Excess Linalool

The behaviour of hop‐derived monoterpene alcohols during fermentation by lager yeast was previously investigated in this laboratory. It was suggested that the concentration of geraniol and β‐citronellol in the finished beer increased depending on the initial concentration of geraniol in the wort. In addition, an additive effect among linalool, geraniol and β‐citronellol was found and 5 ug/L of geraniol and β‐citronellol was enough for this effect. In this paper, conditions regarding the enrichment of the initial concentration of geraniol in the wort were investigated. From the screening of various hop cultivars, Citra hop was selected as a geraniol‐rich cultivar. In addition, it was observed that coriander seed, which can be used in beer production as a flavourant, contained not only linalool but also geraniol at high levels. The use of Citra hop or coriander seed was effective for enriching the concentration of geraniol and β‐citronellol in the finished beers. In the Citra beer and in the coriander beer, the content of linalool was excess in comparison with the content of geraniol and β‐citronellol. Therefore, the synergy of geraniol and β‐citronellol, under coexistence of excess linalool, was examined. It was found that the flavour impression of excess linalool became more fruity and citrus by coexistence with geraniol and β‐citronellol and that the coexistence of all three monoterpene alcohols was effective for this synergy. The flavour characteristics of the Citra and coriander beer and the importance of geraniol metabolism for a citrus flavour in beer are discussed.     

Study on the curing process for carbon/epoxy composites to reduce thermal residual stress

In this work, a cure monitoring system using dielectrometry and a fiber Bragg grating (FBG) sensor, was devised to measure the dissipation factor and thermal residual stress of carbon fiber-reinforced epoxy composite materials. Three rapid-cooling points, which were based on the cure initiation point, were chosen as test variables to investigate the effect of cure cycle on process-induced internal strain. The internal strains generated in the composite specimens were measured using embedded FBG sensors. Three-point bending tests were conducted to investigate the effect of thermal residual stress on the flexural strength of the composite specimens.     

Anti‐windup algorithm with priority to proportional control output of speed PI controller for precision servo system

A robust servo system is important for performance improvement of motion control systems in several industry applications. Generally, a high‐speed positioning servo system consists of robust control systems with integrator, such as PI controller. The industrial servo system always has the limitation for the capacity of the actuator and power amplifier. An ordinary industrial position servo system often has to deal with the saturation of motor current and motor speed. It is difficult for the high‐speed positioning servo system to keep the robust position control against the saturation of motor current and motor speed. This is the case because an ordinary position servo system has a complicated control structure with many control loops. Hence, it sometimes has a large overshoot and an oscillated response due to the limitation of motor current and motor speed. In order to overcome this problem, this paper proposes a new robust high‐speed positioning servo system considering the saturation of torque current and motor speed. The experimental results show that the proposed robust high‐speed positioning servo system has quick and stable position response for the saturation of motor current and motor speed. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(3): 57–64, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20904     

A servo system of AC motor based on voltage modulation fitting for FPGA and consideration of voltage saturation

This paper proposes a space voltage vector modulation (SVM) method for a speed servo system to obtain a quick current response. The proposed SVM method shortens the control lag time of the conventional SVM inverter. In addition, this proposed method is easily implemented in hardware using an FPGA (Field Programmable Gate Array) because the proposed SVM equations are transformed into expressions that hardly need multiplication. By using the proposed SVM method, the servo system realizes quick and stable current control with wide bandwidth. Moreover, by using PI controllers considering the voltage saturation and the torque limiter to the speed servo system, the servo system carries out stable speed control on voltage saturation. Both the proposed SVM method and the PI controllers considering voltage saturation are applied to the speed servo system of a vector controlled induction motor. The effectiveness of both the proposed SVM method and the PI controllers considering voltage saturation is verified by the experimental results. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 173(1): 60–68, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20989     

Study of rocking motion of rigid body with slide contact

The purpose of this study is to formulate the motion of a rigid body with unilateral contact problems by applying techniques of multibody dynamics and to analyze the issue of rocking condition of rigid bodies with slide contact. In To investigate rocking motion with slide contact, we formulate for dynamics of a simple rigid body system with a unilateral contact model. Judgment for the occurrence of contact between a rigid body and a base is applied. The planar motion of a rigid body system having a simple shape and both with and without slide cases is assumed. Using constraint conditions for the contact as algebraic equations, the rocking motion of the rigid body, including slide and frictional force, is analyzed. The differential algebraic equation is solved by the augmented method with Lagrange multipliers, using generalized coordinates and independent variables that describe the contact points. The influence of the frequency and amplitude of disturbance given to the base is discussed. This paper was presented at the 4th Asian Conference on Multibody Dynamics(ACMD2008), Jeju, Korean, August 20–23, 2008. Keisuke Nozaki is graduate student at Sophia University in Tokyo, Japan. Yoshiaki Terumichi received a Ph.D. degree in Mechanical Engineering from keio University in 1994. Dr. Terumichi is currently a Professor at the Department of Engineering and Applied Sciences at Sophia University in Tokyo, Japan. He is currently contributing as a member of Advisory Boad Eccomas Thematic Conference “Multibody Dynamics 2009” and an editor of the International Journal of System Design and Dynamics of JSME. His research field is on multibody dynamics, vehicle dynamics, and pattern formation phenomena. Kazuhiko Nishimura received a B.S. degree in Aerospace Engineering from the University of Tokyo in 1994. He has worked for the Central Japan Railway Company (CJR) since 1994. As an engineer of the railway industry, he also studied mechanical engineering at the University of Michigan and received his M.S. degree in 2003. He is currently a senior research engineer at Komaki Research Center of CJR and also a Ph. D. candidate at Sophia University. His research/engineering interests are in the area of vehicle/track interaction issues in high speed railway system. Kiyoshi Sogabe received a B.S. degree in Mechanical Engineering from Kyusyu Institute of Technology, Japan. He received M.S. and Dr. Eng degrees from the University of Tokyo in 1971 and 1975, respectively. Dr. Sogabe is currently a Professor in the Department of Engineering and Applied Sciences, Faculty of Science and Technology, Sophia University, Tokyo, Japan. Dr. Sogabe was the Dean of the faculty during April 2004–March 2008. His main research interests are in the field of dynamic analysis of machines and structures, multibody dynamics.     

Scenario study on FBR cycle deployment

A scenario study for fast breeder reactor (FBR) has been carried out. Some major scenarios have been induced from the viewpoints of economics, energy security, reduction of radioactive waste burden, and restriction of natural uranium resources “World natural uranium restriction scenario” among some scenarios has been analyzed in detail and introduced in this paper. The results indicate that FBR should be introduced by the middle of the 21st century at the latest in the world sharing energy supply with other energy resources.     

Hydroxypropylated Tapioca Starch Retards the Development of Insulin Resistance in KKAy Mice, a Type 2 Diabetes Model, Fed a High-Fat Diet

ABSTRACT:  The hypoglycemic and antidiabetic effect of hydroxypropyl tapioca starch (HPTS, degree of substitution = 0.180) was investigated in male KKAy mice. Mice were fed a purified high-fat (20%) diet without or with HPTS (5% or 10%) for 33 d. Gelatinized tapioca starch (TS) was used as a reference. Fasting blood glucose concentrations, days 14 and 28, were significantly lower in the 10% HPTS group compared with the reference. In an oral glucose tolerance test (OGTT), day 28, blood glucose concentrations in the 5% HPTS group, at 60, 90, and 120 min, and in the 10% HPTS group, at 30, 60, and 90 min after oral administration of glucose, were significantly lower compared with the reference. The area under the glucose curve (AUC) for glucose in both HPTS groups was significantly lower compared with the reference. Energy intake was significantly lower in the 10% HPTS group compared with the reference. At the end of the experiment, adiponectin concentrations were significantly higher in the 10% HPTS group compared with the reference. A homeostasis model assessment of insulin resistance (HOMA-IR) tended to be lower in the 10% HPTS group compared with the reference, whereas a quantitative insulin sensitivity check index (QUICKI) was significantly higher in both HPTS groups compared with the reference. These results show that HPTS retards the development of insulin resistance in KKAy mice fed a high-fat diet.