JAEA-Review-2010-065.pdf:15.99MB - 日本原子力研究開発機構

JAEA-Review 2010-065
and biofertilizer microorganisms to obtain new useful varieties. Among the ion-beam
induced 'Sake yeast' mutants, sake was test-brewed with two promising mutants characterized
by sweetness and uniqueness in flavor. Heavy-ion microbeam cell-targeting irradiation
revealed that the formation of DNA double strand break signals in the unirradiated cells 6
hours after irradiation in the target colony and in the untargeted colonies was suppressed by
the addition of chemical scavenger of free radicals or NO scavenger, respectively, suggesting
that reactive oxygen species and NO are initiators/mediators for evoking heavy-ion induced
bystander responses. The positron imaging system has been applied to various practical
topics in agriculture. The symbiotic nitrogen fixation in the nodules of intact soybean plant
was first visualized quantitatively using 13 N-labeled N2 gaseous tracer, whose result leads to a
way to test activity of each nodule under various agricultural conditions.
Radiopharmaceuticals for diagnosis of non-small cell lung cancer and neuroendocrine tumors,
i.e., 76 Br-labeled m-bromobenzylguanidine and 64 Cu-labeled trastuzumab, were successfully
prepared as a new positron emission tomography (PET) probe and evaluated for basic
biological studies. The in-air micro particle-induced X-ray emission (micro-PIXE) system
has been utilized mainly to investigate behavior of intracellular trace elements in bio-medical
samples, such as asbestos lung-tissues, brain slices of restraint stress mice, human cancerous
tissue and so on. The 3D-micro-PIXE system was developed and the 3D-elemental imaging
of a biological sample was demonstrated on this system.
In the field of Advanced Materials, various materials were developed by applying ion- or
electron-irradiation effect: WO3 films with hydrogen gasochromism, -rhombohedral B
superconductors with carrier doping, SiC nanotubes, polymer optical waveguides,
hydrogen-storage alloys, diluted-magnetic semiconductors, polycarbosilane nanofibers, SiC
membranes with gas permeation, nano porous SiC, polymer nanowires and nano-crystallines
of metallic glasses. As for the Material Analysis, Rutherford-backscattering spectrometry
(RBS) with the channeling technique, a powerful tool especially for analysis of thin films, has
been used to examine the lattice disorder at the interface between an epitaxially-grown full
Heusler alloy Fe2MnSi layer and a Ge(111) substrate: The former is important for a spin
injector toward realization of a spin field effect transistor. The RBS technique was also
applied for observation of atomistic mass-transport process in Au/Cu films under centrifugal
forces. On the other hand, a positron-microbeam has recently been developed and applied
for micro-analysis of the vacancy-type defect of nuclear-reactor-related materials. Super
structures on a clean Si(111) surface has been investigated with the use of the
reflection-high-energy-positron-diffraction (RHEPD) technique. A nuclear-reaction-analysis
technique combined with the ion-microbeam technique has been applied for imaging light
elements in matrices such as B in Fe. As for the Novel Technology, radiation chemistry
studies on radiolysis of metal ions and organics were carried out using both 60 Co gamma-rays
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