Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Ishiyama, Shintaro; Imahori, Yoshio*; Itami, Jun*; Koivunoro, H.*
Global Journal of Medical Research; F, 15(4), p.1 - 5, 2015/11
In defining the biological effects of the neutron capture reaction, we have proposed a deterministic parsing model (ISHIYAMA-IMAHORI model) to determine the Compound Biological Effectiveness (CBE) factor in Borono-Phenyl-Alanine (BPA)-mediated Boron Neutron Capture Therapy (BNCT). To determine the CBE factor, we derived new calculation formula founded on the deterministic parsing model with three constants, CBE0, F, n and the eigen value Nth/Nmax. where, Nth and Nmax are the threshold value of boron concentration of N and saturation boron density. In order to determine Nth and Nmax in the formula, sigmoid logistic function was employed for 
B concentration data, Db(t) obtained by dynamic PETtechnique, where, A, a and t0 are constants. From the application of sigmoid function to dynamic PET data, it is concluded that the Nth and Nmax for tissue and tumor are identified with the parameter constants in the sigmoid function in tion as: th b at 0 and max N = D t = N = x.
Ishiyama, Shintaro; Imahori, Yoshio*; Itami, Jun*; Koivunoro, H.*
Journal of Cancer Therapy, 6(8), p.759 - 766, 2015/08
From the concentration of 10BPA drug was intravenously injected into the tumor and normal cells of brain tumor patients measured by dynamic PET method, the CBE factor for the BNCT treatment can be calculated by using ISHIYAMA-IMAHORI model.
-edge jump and shift on white-line of Pd interlayer for trilaminar neutron production target under H
irradiationIshiyama, Shintaro; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*
Journal of Chemistry and Chemical Engineering, 8(9), p.870 - 875, 2014/09
Interlayer Pd for the Li/Pd/Cu neutron target for BNCT (Boron Neutron Capture Therapy) was characterized after 0.1-5 keV H irradiation by XAFS technique, and following conclusions were derived; (1) From the XAFS observation of white line of Pd, remarkable Pd Edge jump was found in 1.1-3 times higher than before irradiation in low irradiation fluence. (2) This fact indicates increase of hole density in Pd 4d-band, whereas no change was observed for XASF spectra of Ag sample under the same irradiation conditions. (3) Remarkable Pd Edge shift of 0.12-0.66 eV was also found with increase of H irradiation energy in low fluence, and drastically decreased after peak in high irradiation energy and fluence.(4)Implanted protons deposited in Pd as negative under the balance of electron population enhanced by proton irradiation and charge transfer.
N synthesized on lithium target for boron neutron capture therapyIshiyama, Shintaro; Baba, Yuji; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*
Nihon Kinzoku Gakkai-Shi, 78(8), p.322 - 325, 2014/08
Times Cited Count：0 Percentile：0.00(Metallurgy & Metallurgical Engineering)To remove high level of contaminants by O and C from LiN surface for boron neutron capture therapy target, high temperature thermal desorption was conducted up to 1123 K in ultra high vacuum and the following results were derived; (1) During thermal desorption up to 1023 K, typical three peaks of vacuum pressure disturbance due to vaporization of contaminants were observed in vacuum pressure-temperature curve. (2) Over-layered contaminants with high melting temperature below 1023 K on LiN surface is completely removed by high temperature thermal desorption up to 1123 K in ultra high vacuum. (3) From these desorption results, it is suggested that these contaminants corresponding to these vaporization peaks are HO and Li compounds with high melting temperature below 1023 K, of which LiOH and LiCO were synthesized by decomposition process of LiN with residual HO and CO in low temperature.
O addition on lithium target for BNCTIshiyama, Shintaro; Baba, Yuji; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*
Nihon Kinzoku Gakkai-Shi, 78(8), p.317 - 321, 2014/08
Times Cited Count：0 Percentile：0.00(Metallurgy & Metallurgical Engineering)Low temperature synthesis of lithium-nitride compound was conducted on the lithium target for BNCT by N/HO mixing gas squirt in the ultra high vacuum chamber, and the following results were derived; (1) Lithium-nitride compound was synthesized on the lithium target under 101.3 Pa N gas squirt at room temperature and in the ultra high vacuum chamber under the pressure of 1
10
Pa. (2) Remarkable contamination by O and C was observed on the lithium-nitride compound synthesized under the squirt pressure of 13.3-80 Pa/1.33-4.7 Pa N/HO mixing gas. (3) No contamination and synthesis of Li-N compound was observed under the squirt pressure of 0.013-0.027 Pa/0-0.005 Pa N/HO mixing gas. (4) Contamination by O and C was enhanced with excessive addition of HO at the pressure of over 1.33 Pa.
N thin layer on lithium target surface for BNCT in N gaseous conditionsIshiyama, Shintaro; Baba, Yuji; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*
Nihon Kinzoku Gakkai-Shi, 78(4), p.137 - 141, 2014/04
Times Cited Count：0 Percentile：0.00(Metallurgy & Metallurgical Engineering)To prevent vaporization damage of BNCT (Boron Neutron Capture Therapy) lithium target during operation, direct synthesis of LiN thin layer on lithium target surface was demonstrated in 0.1 MPa N gas at temperature below 548 K and the following conclusions were derived; (1) Synthesis of LiN thin layer on lithium surface was confirmed after nitridation at 276
548 K with surface contamination by oxygen and carbon. (2) Rapid nitridation over 1-5wt.%/min was observed above Li melting temperature, whereas slow reaction under 0.02-0.5 wt.%/min below melting temperature. (3) During nitridation, removal of oxygen contamination on LiN thin layer is taken place by nitrogen below Li melting temperature.
irradiation to Li/Pd/Cu trilaminar neutron production target for BNCTIshiyama, Shintaro; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*
Materials Transactions, 55(4), p.658 - 663, 2014/03
Times Cited Count：3 Percentile：16.65(Materials Science, Multidisciplinary)The Li/Pd/Cu trilaminar structures of the synthesized target for BNCT were characterized under 3keV H irradiation by XPS and XAFS technique, which provides structural/electronic properties of solids, and information about the local structure, such as the nature and number of surrounding atoms and inter-atomic distances. Following conclusions were derived; (1) Pd-Cu physical bonding was produced between the Pd and Cu interface by electro-less plating Pd deposition on a high purity Cu plate (2) From the XAFS observation of white line of Pd, the Pd 
3 Edge jump was found after H irradiation, this fact indicates increase of hole density in Pd 4
-band. (3) 0.9 eV chemical shift was also observed in Pd 3 white line for Pd/Cu samples, which will affect the quality of the Li/Pd/Cu target due to the formation of PdH
in palladium insert layer.
N synthesized on lithium target for boron neutron capture therapyIshiyama, Shintaro; Baba, Yuji; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*
Materials Transactions, 55(3), p.539 - 542, 2014/01
Times Cited Count：2 Percentile：11.62(Materials Science, Multidisciplinary)To remove high level of contaminants by O and C from LiN surface for BNCT target, high temperature thermal desorption was conducted up to 1123 K in ultra high vacuum and the following results were derived; (1) During thermal desorption up to 1023 K, typical three peaks of vacuum pressure disturbance due to vaporization of contaminants were observed in vacuum pressure-temperature curve. (2) Over-layered contaminants with high melting temperature below 1023 K on LiN surface is completely removed by high temperature thermal desorption up to 1123 K in ultra high vacuum. (3) From these desorption results, it is suggested that these contaminants corresponding to these vaporization peaks are HO and Li compounds with high melting temperature below 1023 K, of which LiOH and LiCO were synthesized by decomposition process of LiN with residual HO and CO in low temperature.
O addition on lithium target for BNCTIshiyama, Shintaro; Baba, Yuji; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*
Materials Transactions, 54(12), p.2233 - 2237, 2013/12
Times Cited Count：5 Percentile：30.54(Materials Science, Multidisciplinary)Low temperature synthesis of lithium-nitride compound was conducted on the lithium target for BNCT by N/HO mixing gas squirt in ultra high vacuum chamber, and the following results were derived; (1) Lithium-nitride compound was synthesized on lithium target under 101.3 PaN gas squirt at room temperature and 1 10 Pa in ultra high vacuum chamber. (2) Remarkable contamination by O and C was observed on the lithium-nitride compound synthesized by 13.3 80 Pa/1.33 4.7 Pa N/HO mixing gas squirt. (3) No contamination and synthesis of Li-N compound was observed at 0.013 0.027 Pa/0 0.005 Pa N/HO squirt. (4) Contamination by O and C is enhanced with excessive addition of over 1.33 Pa HO addition.
lithium deposition and ion implantationIshiyama, Shintaro; Baba, Yuji; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*
Nihon Kinzoku Gakkai-Shi, 77(11), p.509 - 513, 2013/11
Times Cited Count：1 Percentile：10.07(Metallurgy & Metallurgical Engineering)To testify thermal stability of the BNCT neutron target synthesized by lithium deposition and ion implantation, laser heating test of the LiN/Li/Cu tri-layered target was conducted in high vacuum chamber of 10
Pa and thermal stability of the tri-layered target was characterized by X-ray photoelectron spectroscopy. Following conclusions were derived; (1) The LiN/Li/Cu tri- layered target with very low oxide and carbon contamination was synthesized by lithium deposition and ion implantation techniques without HO and O additions (2) The starting temperature of evaporation of the LiN/Li/Cu tri-layered target increased by 120 K compared to that of the Li/Cu target and (3) frequent repair synthesis of the damaged LiN/Li/Cu tri-layered target caused by evaporation is possible.
lithium deposition and ion implantationIshiyama, Shintaro; Baba, Yuji; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*
Materials Transactions, 54(9), p.1760 - 1764, 2013/09
Times Cited Count：4 Percentile：26.45(Materials Science, Multidisciplinary)LiN synthesis on Li deposition layer was conducted without HO and O by lithium deposition in high vacuum chamber of 10 Pa and ion implantation techniques and the thermo-chemical stability of the LiN/Li/Cu tri-layered target under laser heating and air exposure was characterized by X-ray photoelectron spectroscopy. Following conclusions were derived; (1) LiN/Li/Cu tri- layered target with very low oxide and carbon contamination was synthesized by lithium deposition and ion implantation techniques without HO and O additions and frequent synthesis of the target is possible. (2) The evaporating temperature of Li deposited layer increased by 120 K after forming the LiN layer on the surface of Li. (3) Remarkable oxidation and carbon contamination were observed on the surfaces of Li/Cu and LiN/Li/Cu after air exposure and these contaminated compositions formed on the surface of LiN/Li/Cu was not removed by Ar heavy sputtering.
N thin layer on lithium target surface for BNCT in N gaseous conditionsIshiyama, Shintaro; Baba, Yuji; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*
Materials Transactions, 54(9), p.1765 - 1769, 2013/09
Times Cited Count：5 Percentile：30.54(Materials Science, Multidisciplinary)To prevent vaporization damage of BNCT (Boron Neutron Capture Therapy) lithium target during operation, direct synthesis of LiN thin layer on lithium target surface was demonstrated in 0.1 MPa N gas at temperature below 548 K and the following conclusions were derived; (1)Synthesis of LiN thin layer on lithium surface was confirmed after nitridation at 276548 K with surface contamination by oxygen and carbon. (2) Rapid nitridation over 15wt.%/min was observed above Li melting temperature, whereas slow reaction under 0.020.5wt.%/min below melting temperature. (3) During nitridation, removal of oxygen contamination on LiN thin layer is taken place by nitrogen below Li melting temperature.
lithium deposition and ion implantationIshiyama, Shintaro; Baba, Yuji; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*
Nuclear Instruments and Methods in Physics Research B, 293, p.42 - 47, 2012/12
Times Cited Count：13 Percentile：67.71(Instruments & Instrumentation)To achieve high performance of BNCT (Boron Neutron Capture Therapy) device, lithium nitride target for neutron production was synthesized by in-situ vacuum deposition and nitridation techniques. Following conclusions were derived; (1) Uniform lithium layer of a few hundreds nanometer was formed on Pd/Cu multilayer surface by vacuum deposition technique using metallic lithium as a source material. (2) Lithium nitrides were formed by nitridation by the implantation of low-energy nitrogen ions on the deposited lithium layer surface. The chemical states of the nitridated zone were close to the stoichiometric lithium nitride, LiN. (3) This nitridated zone formed on surface of four layered lithium target is stable for three months in air condition. The nitridation is effective to protect lithium target from degradation by unfavourable reactions.
Ishiyama, Shintaro; Baba, Yuji; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*
Nuclear Instruments and Methods in Physics Research B, 288, p.18 - 22, 2012/10
To achieve high performance of BNCT (Boron Neutron Capture Therapy) device, lithium target for neutron production was redesigned, and the layered structures of the synthesized target were characterized. Following conclusions were derived; (1) Uniform lithium layers with the thickness from 1.6 nm to a few hundreds nanometer were formed on Pd/Cu multilayer surface by in-situ vacuum deposition technique using metallic lithium as a source material. (2) Re-deposition of lithium layer on Li surface can be achieved by in-situ vacuum deposition technique. (3) Small amount of water and carbonate was observed on the top surface of Li. But the thickness of the adsorbed layer was less than monolayer, which will not affect the quality of the Li target. (4) The formation of Pd-Li alloy layer was observed at the Pd and Li interface. The alloy layer would contribute to the stability of the Li layer.
Ishiyama, Shintaro; Baba, Yuji; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*
Nuclear Instruments and Methods in Physics Research B, 288, p.18 - 22, 2012/10
Times Cited Count：15 Percentile：71.81(Instruments & Instrumentation)For the purpose of avoiding the radiation blistering of the lithium target for neutron production in BNCT (Boron Neutron Capture Therapy) device, trilaminar Li target, of which palladium thin layer was inserted between cupper substrate and Li layer, was newly designed. In-situ vacuum deposition and electrolytic coating techniques were applied to validate the method of fabrication of the Li/Pd/Cu target, and the layered structures of the synthesized target were characterized. In-situ vacuum re-deposition technique was also established for repairing and maintenance for lithium target damaged. Following conclusions were derived; (1) Uniform lithium layers with the thickness from 1.6 nm to a few hundreds nanometer were formed on Pd/Cu multilayer surface by in situ vacuum deposition technique using metallic lithium as a source material. (2) Re-deposition of lithium layer on Li surface can be achieved by in situ vacuum deposition technique.
Kobayashi, Toru*; Harata, Yasuo*; Matsufuji, Naruhiro*; Hasegawa, Tomoyuki*; Endo, Akira; Moribayashi, Kengo; Akahane, Keiichi*; Uehara, Shuzo*; Imahori, Yoshio*; Kato, Yo*; et al.
JAEA-Review 2006-002, 101 Pages, 2006/02
JAEA-Review-2006-002.pdf:5.53MB
This report provides an analysis of the results of the survey conducted among field experts regarding the data on atoms, molecules, and atomic nuclei used in medical applications. The important results are summarized as follows: First, the importance of the basic data for disciplines involved in medical research, i.e. physics and engineering, chemistry, pharmacology, biology, and the related data which are applied directly in medicine were identified. The related data are of greater importance in direct medical application compared to conventional basic data. Therefore, the data related to biology should be prepared in consideration of their convenient usage. Second, regarding the fundamental data on atoms, molecules and atomic nuclei related to medicine, the present data was able to approximately cope with the demands of many medical cases that needed data on quality, quantity, precision, etc. However, we found situations particularly in the IT community where comprehensively organized data was urgently needed. The data to be used for practical implementation must contain the specialized data for medical physics and biology. Finally, the significance of the continuity in the planned completion of the basic data was confirmed for the development of the associated fields. The expansion and completion of basic data should be done continuously and effectively while considering the limitation in resources and manpower.
Ishiyama, Shintaro; Baba, Yuji; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*
no journal, ,
To achieve high performance of BNCT (Boron Neutron Capture Therapy) device, LiN/Li/Pd/Cu four layered Li target was designed and the structures of the synthesized four layered target were characterized by X-ray photoelectron spectroscopy. For the purpose of avoiding the radiation blistering and lithium evaporation, vacuum deposition and nitridation techniques were established for production and repairing maintenance of the lithium target. Following conclusions were derived;(1) Uniform lithium layer of a few hundreds nanometer was formed on Pd/Cu multilayer surface by vacuum deposition technique using metallic lithium as a source materialand lithium nitrides were formed by nitridation reaction by the implantation of low-energy nitrogen ions on the deposited lithium layer surface. (2) This nitridated zone formed on surface of four layered lithium target is stable for a long time in air condition.
Ishiyama, Shintaro; Baba, Yuji; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*
no journal, ,
LiN synthesis on Li deposition layer was conducted without HO and O by in-situ lithium deposition in high vacuum chamber of 10 Pa and ion implantation techniques and the thermo-chemical stability of the LiN/Li/Cu tri-layered target for Boron Neutron Capture Therapy (BNCT) under laser heating and air exposure was characterized by X-ray photoelectron spectroscopy (XPS). Following conclusions were derived; (1) LiN/Li/Cu tri-layered target with very low oxide and carbon contamination was synthesized by in-situ lithium vacuum deposition and N ion implantation without HO and O additions, (2) The starting temperature of evaporation of LiN/Li/Cu tri-layered target increased by 120 K compared to that of the Li/Cu target and (3) Remarkable oxidation and carbon contamination were observed on the surface of LiN/Li/Cu after air exposure and these contaminated compositions was not removed by Ar heavy sputtering.
Ishiyama, Shintaro; Imahori, Yoshio*
no journal, ,
For the purpose of avoiding the radiation blistering of the lithium target for neutron production in BNCT (Boron Neutron Capture Therapy) device, trilaminar Li target, of which palladium thin layer was inserted between cupper substrate and Li layer, was newly designed. The Li/Pd/Cu trilaminar structures of the synthesized target were characterized under 3 keV H
irradiation by XPS and XAFS technique, which provides structural/electronic properties of solids, and information about the local structure, such as the nature and number of surrounding atoms and inter-atomic distances. Following conclusions were derived; (1) Pd-Cu physical bonding was produced between the Pd and Cu interface by electro-less plating Pd deposition on a high purity Cu plate (2) From the XAFS observation of white line of Pd, the Pd L3 Edge jump was found after H irradiation, this fact indicates increase of hole density in Pd 4d-band.
Kobayashi, Toru*; Harata, Yasuo*; Matsufuji, Naruhiro*; Hasegawa, Tomoyuki*; Endo, Akira; Moribayashi, Kengo; Akahane, Keiichi*; Uehara, Shuzo*; Imahori, Yoshio*; Kato, Yo*; et al.
no journal, ,
no abstracts in English
