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  • Author or Editor: H. Furukawa x
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Abstract  

Japanese iron artifacts contain a small amount of charcoal which was used in manufacturing. We developed a wet method of carbon extraction from the iron samples for AMS radiocarbon dating. The method consists of dissolution of iron with a Cu2+ solution and dissolution of deposited Cu in HCl. High extraction yields (80–90%) and low contamination by modern carbon were achieved by the wet method.

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Abstract  

The recoil properties of 26 radionuclides produced in the photonuclear reactions on Cu at bremsstrahlung end-point energies (E 0) of 250 to 1000 MeV have been investigated using the thick-target thick-catcher method. Kinematic properties of the product nuclei were calculated by the two-step vector velocity model. The calculated mean kinetic energies,T, of product nuclei increase with increase of the mass difference between products and target, reflecting the resonance natures and absorption mechanisms. TheT atE 0≥600 MeV were well reproduced by a calculation performed by PICA code byGabriel andAlsmiller atE 0=400 MeV, except for (γ,xn) products by giant-resonance.

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Forty-five broiler arcasses from 6 different flocks were condemned due to liver lesions at processing meat inspection, and collected for pathological and bacterial examination. All affected chickens showed liver enlargement with distrahepatic bile ducts contained yellow inspissated cream-coloured material. Histopathologically, extensive proliferation of bile ductules with fibrosis was observed in interlobular connective tissue, and it spread to form bridges with adjoining triads. Destruction and obstruction of portal bile ducts with multiple granulomas due to bacterial infection and outflow of the bile were frequently observed.Many-Gram-positive bacilli were seen in the lesions, and they were identified asClostridium perfringensby indirect immunofluores en ecstaining technique.Clostridium perfringenswas isolated from affected livers. These findings are consistent with cholangiohepatitis. Therefore, it is suggested thatC. perfringensmight be important in the pathogenesis of cholangiohepatitis in broiler chickens.

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Abstract  

Concentrations of eighteen trace elements at the sediment-water interface in Biwa Lake were determined by neutron activation analysis. Release of iron, manganese and arsenic from the sediment to the pore water was observed under anoxic conditions. The concentrations of Sb in the pore water as well as Na were nearly constant between the surface and the depth of 40 cm. The behavior of Sb differed from that of As at the sediment-water interface, since the partition coefficient of Sb differed from that of As.

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Abstract  

Nuclear reactions of165Ho induced by 1.0 GeV15N or 1.8 GeV14N ions and those of141Pr induced by 2.3 GeV or 3.8 GeV40Ar ions have been studied by off-line -ray spectrometry. Mass distributions of the products were confirmed to reveal a limiting characteristics at projectile energies beyond 2 GeV. Longitudinal momentum transfer was measured with a thick-target-thick-catcher technique. The results demonstrated that a provisional limiting of the recoil velocity appears in the energy range of 2–10 GeV, besides the ultimate limiting condition already pointed out. The coincidence in the onset energy of the limiting behavior was interpreted as the result of the existence of the limit heating of nucleus.

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Abstract  

We present water imaging of a plant sample both by neutron beam and positron emission tracer imaging system (PETIS). The former method provided static water profile in a plant sample as well as that in the vicinity of a root imbedded in soil. Not only X-ray film but also CT method using a cooled CCD camera is presented. Through non-destructive water image in an X-ray film, root development as well as 2-dimensional water movement toward the root was analyzed. Spatial water image was constructed from 180 CT projection images, taken at an interval of one degree while rotating the sample, through a CCD camera. In the case of a soybean root, there was a water gradient toward a root in soil and gave minimum value at about 1 mm far from the surface of a root. The water absorbing part in a root was gradually shifted downward with the root development. We also present real time water movement by PETIS, where water was labeled with a positron emitting nuclide, 15O. The transportation of 15O-water within a plant was relatively slow and water uptake was observed only at the lowest internode, between a root and the first leaf, during 20-minute measurement.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
A. Shinohara
,
T. Muroyama
,
T. Miura
,
A. Yokoyama
,
K. Takamiya
,
T. Kaneko
,
T. Saito
,
J. Sanada
,
H. Araki
,
S. Kojima
,
Y. Hamajima
,
H. Muramatsu
,
H. Baba
, and
M. Furukawa

Abstract  

Pionic X-rays and π0 decays were measured for gas mixtures of H2/D2/CH4+SF6/Ar and the individual pure gases. Chemical effects on the pion transfer process from pionic hydrogen to other atoms were revealed by the pionic X-ray spectrum. The changes of the intensity patterns of pionic X-rays were compared with the predictions by a cascade calculation taking the transfer process into account. The mechanism of pion transfer process was discussed based on the results for gas phase and the previous ones for liquid phase.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
T. Muroyama
,
A. Shinohara
,
T. Saito
,
A. Yokoyama
,
K. Takamiya
,
S. Morimoto
,
K. Nakanishi
,
H. Baba
,
T. Miura
,
Y. Hamajima
,
T. Kaneko
,
H. Muramatsu
,
S. Kojima
, and
M. Furukawa

Abstract  

Annihilation γ-rays of π0 and pionic X-rays were measured in the gas mixtures of H2+Z and CH4+Z systems (Z=He, Ne, Ar and Kr). Pion capture probability of hydrogen atom was obtained from the annihilation γ-ray counts and the capture probability of Z atom was obtained from the pionic X-ray intensities. Transfer rates were determined from the data based on a combined large mesomolecular model. The transfer rates obtained were smaller than the systematics of the Russian group. Difference in the transfer rate between the gas and the liquid phases was found by a comparison of the present results with our previous ones.

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