Japan’s Food Labeling Regulations and Enforcement Measures

Tanaka Yoshihiro 식품안전정보원 2022 식품법과 정책 Vol.- No.3

Core/Shell Structure of Ferroelectric (Ba0.94Ca0.06)TiO3 Grains

Yoshihiro Iwahori,Hiroshi Tanaka,Masaki Takata,Yoshihiro Terado,Chikako Moriyoshi,Yoshihiro Kuroiwa 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.2

The crystal structure of ferroelectric (Ba0.94Ca0.06)TiO3 (BCT) with small grains on an average of 1-μm in size has been investigated by using high-energy synchrotron-radiation powder-diffraction. A core/shell structure model, in which the grain consists of a core with tetragonal symmetry covered all over with a thin tetragonal shell with low tetragonality, is proposed and provides a markedly contrast with the core/shell structure of pure BaTiO3, which is generally known to have a shell with cubic symmetry. The higher permittivity of BCT is attributed to the characteristic shell structure with tetragonal symmetry. A change in the chemical bonding nature of BCT on the ferroelectric phase transition is clearly demonstrated in the electron charge density map. The crystal structure of ferroelectric (Ba0.94Ca0.06)TiO3 (BCT) with small grains on an average of 1-μm in size has been investigated by using high-energy synchrotron-radiation powder-diffraction. A core/shell structure model, in which the grain consists of a core with tetragonal symmetry covered all over with a thin tetragonal shell with low tetragonality, is proposed and provides a markedly contrast with the core/shell structure of pure BaTiO3, which is generally known to have a shell with cubic symmetry. The higher permittivity of BCT is attributed to the characteristic shell structure with tetragonal symmetry. A change in the chemical bonding nature of BCT on the ferroelectric phase transition is clearly demonstrated in the electron charge density map.

Usefulness of Virtual Fluoroscopy in Emergency Interventional Radiology

Yoshihiro Tanaka,Akitoshi Oosone,Asuka Tsuchiya 대한영상의학회 2020 대한영상의학회지 Vol.81 No.4

Interventional radiology (IR) embolization requires image guidance to steer catheters to the site of bleeding, where embolic agents such as Gelfoam or coils are administered to stem blood flow. In addition to treating iatrogenic trauma, embolization is suitable for injuries precluding surgery such as blush-bleeding of the liver or kidney and for locating and treating intimal blood vessel tears. However, during hospital off-hours (such as nights and holidays), experienced IR personnel are not always available. In such situations, there is a dire need to build a coordinated IR team to treat seriously injured patients rapidly and reliably. This article reviews the current principles and techniques used in IR such as virtual fluoroscopy and their usefulness, and makes a convincing case for emergency IR.

일본 완전통합교육(교류 및 공동학습)의 현상과 과제

Yoshihiro Tanaka 국립특수교육원 2005 국제세미나 자료집 Vol.2005 No.-

Atomic Replacement Effect on Electron Charge Density of Perovskite Oxides

Yoshihiro Kuroiwa,Akikatsu Sawada,Eiji Nishibori,Hiroshi Tanaka,Jimpei Harada,Makoto Sakata,Masaki Takata,Shinobu Aoyagi 한국물리학회 2003 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.42 No.IV

Charge density distributions of cubic SrTiO3 have been investigated related to the atomic replacement eect on the phase transition, by analyzing the synchrotron-radiation X-ray powder-diraction data by the MEM(Maximum Entropy Method)/Rietveld method. The chemical bonding natures between constituent atoms in cubic SrTiO3 are compared with those in cubic BaTiO3 that we investigated previously at the same temperature. The Characteristic charge density distribution around the O atom, which may present a clue what kind of phase transition occurs in the cubic perovskite oxide, is found in SrTiO3.

Atomic Replacement Eect on Electron Charge Density of Perovskite Oxides

Yoshihiro Kuroiwa,Shinobu Aoyagiy,Akikatsu Sawada,Eiji Nishibori,Masaki Takata,Makoto Sakata,Hiroshi Tanaka,Jimpei Harada 한국물리학회 2003 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.42 No.IV

Charge density distributions of cubic SrTiO3 have been investigated related to the atomic replacement eect on the phase transition, by analyzing the synchrotron-radiation X-ray powder-diraction data by the MEM(Maximum Entropy Method)/Rietveld method. The chemical bonding natures between constituent atoms in cubic SrTiO3 are compared with those in cubic BaTiO3 that we investigated previously at the same temperature. The Characteristic charge density distribution around the O atom, which may present a clue what kind of phase transition occurs in the cubic perovskite oxide, is found in SrTiO3.

Pressure filtration of colloidal SiC particles

Yoshihiro Hirata,Yosuke Tanaka,Seiya Nakagawa,Naoki Matsunaga 한양대학교 세라믹연구소 2009 Journal of Ceramic Processing Research Vol.10 No.3

The consolidation behavior of colloidal SiC particles (30 or 800 nm diameter) with and without polyacrylic ammonium (dispersant, PAA) at pH 7 was examined using a developed pressure filtration apparatus in the pressure range from 100 kPa to 19 MPa at a constant crosshead speed or at a constant compressive pressure of a piston. In the electrostatically-stabilized colloidal suspensions (5 vol%-30 nm SiC (powder A), 30 vol%-800 nm SiC (powder B)) without PAA, a phase transition from a well-dispersed suspension to a flocculated suspension occurred when the applied pressure exceeded a critical pressure (ΔPtc = 0.2−0.4MPa). The addition of PAA suppressed the phase transition. The height of the compressive piston as a function of filtration time at a constant applied pressure was simulated by an established filtration theory for a well-dispersed suspension and a newly-developed filtration theory for a flocculated suspension. The experimental results for both the suspensions of powders A and B with and without PAA were simulated well by the new model for flocculated suspension. The packing density of consolidated powders A and B in the filtration apparatus depended on the applied pressure, but the density after calcination was independent of the compressive pressure. The consolidation behavior of colloidal SiC particles (30 or 800 nm diameter) with and without polyacrylic ammonium (dispersant, PAA) at pH 7 was examined using a developed pressure filtration apparatus in the pressure range from 100 kPa to 19 MPa at a constant crosshead speed or at a constant compressive pressure of a piston. In the electrostatically-stabilized colloidal suspensions (5 vol%-30 nm SiC (powder A), 30 vol%-800 nm SiC (powder B)) without PAA, a phase transition from a well-dispersed suspension to a flocculated suspension occurred when the applied pressure exceeded a critical pressure (ΔPtc = 0.2−0.4MPa). The addition of PAA suppressed the phase transition. The height of the compressive piston as a function of filtration time at a constant applied pressure was simulated by an established filtration theory for a well-dispersed suspension and a newly-developed filtration theory for a flocculated suspension. The experimental results for both the suspensions of powders A and B with and without PAA were simulated well by the new model for flocculated suspension. The packing density of consolidated powders A and B in the filtration apparatus depended on the applied pressure, but the density after calcination was independent of the compressive pressure.

Thermodynamics of colloidal suspensions

Yoshihiro Hirata,Yosuke Tanaka 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.4

This paper succeeds in the description of activity (a), chemical potential (μ), and their thermodynamic relations of dispersed and flocculated particles of a one-component colloidal system. The activity of dispersed particles (ad) is expressed by Henry’s law and equal to the product of the molar fraction (α) of dispersed particles in a suspension and the activity coefficient (γ0) expressed by Vi/Vmax (Vi : total volume fraction of dispersed and flocculated particles, Vmax : maximum packing density of particles). The activity of flocculated particles (ag) follows Raoult’s law and is expressed as (1 − α) using the Gibbs-Duhem equation. The μ value is represented by the defined activity. The difference of μ for the dispersed and flocculated particles (Δμ = μg− μd) was used to evaluate the stability of the colloidal state. The Δμ value was also coupled with the activation energy (ΔGm) for the formation of particle clusters from the dispersed state. The enthalpy term (ΔHm) in the activation energy is equivalent to the maximum value of the interaction energy (Ei(max)) as a function of distance between two particles in the DLVO theory. Based on the above analysis, a colloidal phase diagram for one-component systems of 10-1000 nm diameters was constructed. This phase diagram explains well the experimentally-determined packing density for dispersed and flocculated suspensions. This paper succeeds in the description of activity (a), chemical potential (μ), and their thermodynamic relations of dispersed and flocculated particles of a one-component colloidal system. The activity of dispersed particles (ad) is expressed by Henry’s law and equal to the product of the molar fraction (α) of dispersed particles in a suspension and the activity coefficient (γ0) expressed by Vi/Vmax (Vi : total volume fraction of dispersed and flocculated particles, Vmax : maximum packing density of particles). The activity of flocculated particles (ag) follows Raoult’s law and is expressed as (1 − α) using the Gibbs-Duhem equation. The μ value is represented by the defined activity. The difference of μ for the dispersed and flocculated particles (Δμ = μg− μd) was used to evaluate the stability of the colloidal state. The Δμ value was also coupled with the activation energy (ΔGm) for the formation of particle clusters from the dispersed state. The enthalpy term (ΔHm) in the activation energy is equivalent to the maximum value of the interaction energy (Ei(max)) as a function of distance between two particles in the DLVO theory. Based on the above analysis, a colloidal phase diagram for one-component systems of 10-1000 nm diameters was constructed. This phase diagram explains well the experimentally-determined packing density for dispersed and flocculated suspensions.

Influence of Distance from Home to Hospital on Survival among Lung Cancer Patients

Tanaka, Rina,Matsuzaka, Masashi,Nakaji, Shigeyuki,Sasaki, Yoshihiro Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.11

The objective of this study was to clarify how distance from place of residence to the nearest specialist cancer hospital affects the survival of lung cancer patients and the treatment received. For all patients diagnosed with lung cancer in the Aomori cancer registry database for the period from 2009 to 2011 (n=3,986). The distance to the treating hospital was measured as the straight line from a person's place of residence, and compared with findings from the Ederer II method for calculating relative survival. Information on treatments given was obtained by data extraction. We defined a hospital having respiratory medicine as specialist, while all private hospitals and clinics were included in the general category. Patients attending specialist hospitals numbered 2,548 (67.0%), and those treated at general institutions were 1,255 (33.0%). The patients who had the lowest relative survival with localized lesions lived <20 km from general hospitals and clinics. With more advanced stages, relative survival of those living <20 km from a specialist hospital was the lowest. Although the survival rate was not affected by the distance between place of residence and hospital, even when patients are diagnosed at a localized stage at a general hospital or clinic within 20 km from their home, they did survive longer in comparison with patients diagnosed at a specialist hospital.

A New Method for Evaluating the Electrostatic Potential by Using a MEM X-Ray Diffraction Analysis

Hiroshi Tanaka,Yoshihiro Kuroiwa,Masaki Takata 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.2

Recently, a new method was proposed for evaluating the electrostatic potential in crystalline solids from X-ray diffraction data. It is based on the electron charge density, which is analyzed by using the maximum entropy method (MEM) and Ewald's technique. The algorithm is almost parameter-free, and the electrostatic potential can be evaluated even by those with little or no experience. In this article, the method is reviewed briefly, and an application to a typical ionic crystal, NaCl, is introduced. Recently, a new method was proposed for evaluating the electrostatic potential in crystalline solids from X-ray diffraction data. It is based on the electron charge density, which is analyzed by using the maximum entropy method (MEM) and Ewald's technique. The algorithm is almost parameter-free, and the electrostatic potential can be evaluated even by those with little or no experience. In this article, the method is reviewed briefly, and an application to a typical ionic crystal, NaCl, is introduced.