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Abstract  

The retentions of cobalt, copper and zinc recoils were studied in the mixed crystal system of -cobalt phthalocyanine and -zinc phthalocyanine. It was suggested that a part of the retentions of cobalt and zinc recoils was due to a competitive process. The relationship between the retentions of the zinc recoils and their recoil energy in different matrices was discussed.

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Summary

This study reports the effect of a nonionic perfluorinated surfactant, N-polyoxyethylene-N-propyl perfluorooctane sulfonamide (PFOSA), as additive of background electrolyte on capillary electrophoresis (CE) of common inorganic cations. The association constants (K ass) for PFOSA estimated from the electrophoretic mobility of analyte cations were the order of Mg2+ > Ca2+ > Sr2+ > K+ ≈ NH4+ > Na+ ≈ Li+. The K ass values were larger than those for zwitterionic and nonionic surfactants with hydrocarbon moiety. Use of PFOSA made another essential contribution to the determination of inorganic cations in a protein-containing sample. This was considered because high solubility of PFOSA for proteins functioned as suppressor for protein adsorption to the capillary wall. Four inorganic cations, Na+, K+, Mg2+, and Ca2+, in human saliva sample were successfully determined by sample injection without any pretreatments except for filtration and dilution.

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Abstract  

The chemical effect of7Be recoils formed through a12C/, n/7Be process from ligand carbon atoms was investigated in a several phthalocyanines. It was found that7Be-phthalocyanine was synthesized by7Be recoil. Net radiochemical yields of7Be-phthalocyanine were estimated to be 10–20% for copper and zinc phthalocyanines, while for metal-free phthalocyanines, yields above 90% were obtained.

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Abstract  

The complexation of β-lactam antibiotics, amoxicillin (AMPC), ampicillin (ABPC) and benzylpenicillin (PCG), with 2-hydroxypropyl-β-cyclodextrin (HPCD) was studied at various pH values using microcalorimetry, 1H NMR spectroscopy, and molecular dynamic simulation. In the strong acid solution, two different types of inclusion complex with a 1:1 stoichiometry, Complex I with a phenyl ring of β-lactam antibiotics penetrated into the cavity of HPCD and Complex II with a penam included in the cavity, were formed by hydrophobic interaction, and Complex II was more stable than Complex I. In aqueous solution at pH≥4.5, only Complex I was formed, where the penam of PCG was more deeply penetrated into the cavity to keep it stable than those of AMPC and ABPC. The charged carboxyl-group on the penam was less affinity to form Complex II.

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Abstract  

A series of metal -diketonates were irradiated with bremsstrahlung of maximum energy of 50 MeV and the recoil behavior of7Be, formed from12C of ligands through12C(, n)7Be reaction, was investigated.7Be nuclides thus formed were detected partially as central metal atoms of the complexes. Complex yields of7Be were compared and an anomalously high yield was observed in tris-acetylacetonatocobalt(III) [Co(acac)3].

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
T. Nakamura
,
S. Kojima
,
T. Ohta
,
M. Nishida
,
A. Rakowski
,
A. Ikeda
,
H. Oda
, and
E. Niu

Abstract  

14C variations of atmospheric CO2 as well as carbonaceous fraction of living materials, such as collagen from tooth and bone, tissue, skin, hair, nail, etc., of modern humans are influenced by 14C produced artificially by nuclear bomb tests in the atmosphere from late 1950s to early 1960s. By careful investigation of 14C concentration of tree rings and human body samples formed in this time intervals, we can establish a relationship of their 14C concentrations with calendar year. By applying this relation to a sample whose 14C concentration can be measured, we can estimate the formation age of the sample. In addition, sources of the chemicals that were used in some criminal cases can be possibly identified, by their carbon isotope ratios (13C/12C and 14C/12C). This method of age determination has been applied to a forensic study, i.e., two criminal cases of murder. For each case, by comparing the measured 14C abundances of several pieces of hair and one tooth (the third molar) from the body with the annual change on concentrations of bomb-produced 14C, the time of death of the body and the age of the victim were estimated. The estimated values were consistent with the real ones that were revealed by the confession of the real murderers.

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Abstract  

Fission track /FT/ method and inductively coupled plasma mass spectrometry /ICP-MS/, that is a new analytical technique for the analysis of trace element, were used for the measurement of240Pu/239Pu ratios in environmental samples. The results obtained by both methods are in agreement within the relative deviation of 9–13%. The precision in ICP-MS was found to be better than in it the FT-method. These methods are applicable to measure the Pu isotopes ratio at low concentration levels in environmental samples.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Chang-Kyu Kim
,
A. Takaku
,
M. Yamamoto
,
H. Kawamura
,
K. Shiraishi
,
Y. Igarashi
,
S. Igarashi
,
H. Takayama
, and
N. Ikeda

Abstract  

A new analytical technique using ICP-MS was applied to the determination of237Np in some environmental samples. The accuracy and precision of the new method were assessed by comparison with those of conventional NAA and -spectrometric method as well as by analysis of the intercomparison sample of Ravenglass NRPB silt. The results obtained by ICP-MS were in good agreement with those by NAA or -spectrometry at a relative deviation of 2–9%. The detection limit is 0.02 mBq/ml (26 mBq=1 ng).

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