All issues
Volume 69, Issue 7
Displaying 1-7 of 7 articles from this issue
- |<
- <
- 1
- >
- >|
-
Akimasa MASUDA, Kazuya TAKAHASHI, Atsumichi KAWASHIMA1993 Volume 69 Issue 7 Pages 155-160
Published: 1993
Released on J-STAGE: October 13, 2006
JOURNAL FREE ACCESSThe investigations of the isotopic abundance ratios of molybdenum in zircon have shown that the molybdenum isotopic composition obtained reflects two effects: (1) spontaneous fission of 23892U contained in the zircon and (2) double beta decay of 9640Zr. Interestingly, however, the products due to the spontaneous fission appear to have a strange large excess (spike) of 9842Mo. It intrigues us that 92 minus 42 leaves 50, one of the outstanding magic numbers. It is suggested in the present communication that the strange spike of 9842Mo in question can result from a special type of sontaneous fission having essential bearings on the magic number 50 of protons and the “magical” numbers 58 and 92 of neutrons.View full abstractDownload PDF (557K) -
Masuo SUZUKI1993 Volume 69 Issue 7 Pages 161-166
Published: 1993
Released on J-STAGE: October 13, 2006
JOURNAL FREE ACCESSA general decomposition theory of ordered exponentials is presented by reducing the problem to the decomposition of ordinary exponential operators in terms of the super-operator _??_ defined by F(t)exp(Δt_??_)G(t)=F(t+Δt)G(t). It is proved that T(exp∫t+ΔttH(s)ds)=exp[Δt(H(t)+_??_)]. Here T denotes the time ordering.View full abstractDownload PDF (529K) -
Hideharu NAKASHIMA, Fuyuki YOSHIDA, Kunihiro NOGUCHI, Hideo YOSHINAGA1993 Volume 69 Issue 7 Pages 167-172
Published: 1993
Released on J-STAGE: October 13, 2006
JOURNAL FREE ACCESSIn order to identify the mechanism originating the threshold stress for the high-temperature deformation of dispersion-strengthened alloys, stress-change tests were conducted during deformation of an Al-1.5 vol%Be alloy. It was found that the instantaneous strain on the increase in applied stress was absolutely elastic when the stress-increment Δσ was below a certain value Δσc, an instantaneous plastic strain was observed for Δσ>Δσc, whereas the strain was always elastic for a stress-decrement. The critical stress Δσc depended on temperature and showed a maximum in a temperature range from 570K to 620K. From these findings it is discussed that the threshold stress should be determined by the Srolovitz mechanism.View full abstractDownload PDF (678K) -
Hiroaki ABE, Chiken KINOSHITA, Yasutaka DENDA, Takeshi SONODA1993 Volume 69 Issue 7 Pages 173-178
Published: 1993
Released on J-STAGE: October 13, 2006
JOURNAL FREE ACCESSIn-situ observation of Ge and Si has been performed under dual-beam irradiation with ions and electrons in the HVEM-accelerator facility at Kyushu University. Damage cascades show up their contrast and increase in number within a few seconds. The cascade contrast features accumulate with ion fluence, eventually leading to saturation. The saturated areal density decreases with increasing electron flux. Based on analyses using kinetic equations, it has been concluded that damage cascades show up their contrast through overlap or help from other damage cascades and that simultaneous electron irradiation eliminates damage cascades through the production of isolated point defects and irradiation-induced migration of point defects.View full abstractDownload PDF (741K) -
Jun KAWAI, Shinjiro HAYAKAWA, Yoshinori KITAJIMA, Setsuo SUZUKI, Kunik ...1993 Volume 69 Issue 7 Pages 179-184
Published: 1993
Released on J-STAGE: October 13, 2006
JOURNAL FREE ACCESSX-ray induced current intensity and Auger electron intensity of a GaAs wafer are measured as a function of the angle of incidence of the x-rays of 2-keV photon energy using synchrotron radiation. It is found that the current intensity curve plotted as a function of the x-ray incident angle resembles the Auger electron intensity curve, but a little difference exists which originates from the difference of the probing depth between the two methods. It is concluded that the Auger electron probes 10-100Å depth and the sample current probes 1-10Å depth when the incident x-rays are totally reflected. On the other hand, x-ray induced current intensity of a Si wafer is measured as a function of incident photon energy in and out of the total reflection condition, and by this way, x-ray absorption fine structure (XAFS) spectra are obtained. It is found that the XAFS measured using the sample current is more surface sensitive (-5Å) than the Auger electron yield (-50Å) when the incident x-rays are totally reflected.View full abstractDownload PDF (610K) -
Akira MURAYAMA, Takakazu SUZUKI, Masanao MATSUI1993 Volume 69 Issue 7 Pages 185-190
Published: 1993
Released on J-STAGE: October 13, 2006
JOURNAL FREE ACCESS9-cis-Retinoic acid and 9, 13-di-cis-retinoic acid were synthesized and their biological effects on human acute promyelocytic cell line HL-60 were analyzed. 9-cis-Retinoic acid was threefold more potent than all-trans-retinoic acid in assays to inhibit growth and to induce differentiation of HL-60 cells. The activity of 9, 13-di-cis-retinoic acid was as high as that of all-trans-retinoic acid. Both 9-cis-retinoic acid and 9, 13-di-cis-retinoic acid acted additively with all-trans-retinc is acid on HL-60 cells. Both 9-cis-retinoic acid and 9, 13-di-cis-retinoic acid acted synergetirally with 1α, 25-dihydroxyvitamin D3 to inhibit HL-60 cell proliferation. Thyroid hormone (T3) did not affect the action of the retinoids on HL-60 cells.View full abstractDownload PDF (535K) -
Yoshiharu TANAKA1993 Volume 69 Issue 7 Pages 191-196
Published: 1993
Released on J-STAGE: October 13, 2006
JOURNAL FREE ACCESSProtein composition of the Drosophila whole thorax was analyzed by two-dimensional polyacrylamide gel electrophoresis (2D-EP) and nonequilibrium pH gradient electrophoresis (NEpHGE). Altogether, approximately 300 protein spots in the thorax were detected reproducibly and 27 proteins had been identified their characteristics. To analyze the differential distribution of the protein spots in two types of muscles, fibrillar and tubular type muscle fibers were individually dissected from the thoraces of freeze-dried flies and were subjected separately to 2D-EP and NEpHGE. 66 protein spots and 14 protein spots were detected specifically in fibrillar muscles and tubular muscles, respectively. 24 protein spots were detected more abundantly in fibrillar muscles than in tubular muscles. 5 protein spots were detected more abundantly in tubular muscles than in fibrillar muscles. 4 proteins existed in both muscles similarly. This study would provide the useful basis for the molecular and genetical studies of Drosophila muscles.View full abstractDownload PDF (2173K)
- |<
- <
- 1
- >
- >|