RADIOISOTOPES
Online ISSN : 1884-4111
Print ISSN : 0033-8303
ISSN-L : 0033-8303
Volume 17, Issue 12
Displaying 1-10 of 10 articles from this issue
  • Toyosaburo TAKEUCHI, Yoshisato TEZUKA, Daisaku MIYATANI, Yoshihumi NAK ...
    1968 Volume 17 Issue 12 Pages 549-554
    Published: December 15, 1968
    Released on J-STAGE: September 07, 2010
    JOURNAL FREE ACCESS
    The autoradiographical method was adapted for the investigation of the reactivity of the preadsorbed hydrogen or ethylene on Cu, Ni and Cu-Ni alloys prepared by various methods.
    3H2 and 14C-ethylene were used as the tracers. The damage effect caused by α-rays and the effect of the sintering by the heat treatment upon the adsorption were observed. Massive alloys and the evaporated films deposited on the cold substratum were used for the tests.
    A great difference was found on the amount of the adsorbed hydrogen between the massive alloys and the evaporated films. The amount of adsorbed hydrogen increased by the damage of α-rays in the case of the massive metal and the film sintered at 250°C. However, the amount decreased in the case of the film sintered at 30°C. It was found that the amount of the adsorbed ethylene was not affected obviously by the composition of the alloy.
    These results suggested that the catalytic activity of metals depends maanty upon the structual factor rather than the electronic factor of the metals.
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  • Mutsuaki SHINAGAWA, Muneaki SENOO, Nobuo TSUJI
    1968 Volume 17 Issue 12 Pages 555-561
    Published: December 15, 1968
    Released on J-STAGE: September 07, 2010
    JOURNAL FREE ACCESS
    Radiopolarography is an analytical method of which use can be made for determining low concentration radioactive element without any nuisance of residual current. Radioactivity of the element deposited on mercury drop is measured and plotted against potential to get a curve similar to polarographic current-potential curve.
    Recently, A.A. Katsanos, et al, reported that radiopolarography can be extended to nonradioactive element in the presence of a radioactive element due to oxidation-reduction replacement. For example, using radioactive 65Zn and natural Mn2+ radiopolarographic waves are obtained at the corresponding half-wave potentials of -1.00 and -1.51 V vs. S.C.E., respectively.
    The depositd manganese is oxidized and replaced by radioactive zinc and gives rise to the second plateau;
    (Hg, Mn) +Zn2+= (Hg, Zn) +Mn2+
    The height of the first plateau is proportional to the concentration of Zn2+ and the difference between those two plateaux is proportional to the concentration of Mn2+ and independent of that of Zn2+, thus allowing the quantitative determination of Mn2+.
    In the present experiment, the authors report a new type cell which is made of two separated cells (Fig. 1) : in the first cell, there is a solution of non-radioactive element (Mn2+), and in the second cell, there is a solution of radioactive element (65Zn2+) .
    Mercury drops with electrodeposited manganese in the first cell fall into the second cell, in which it is oxidized and replaced by 65Zn2+.
    So, the labeled mercury drops give a polarographic plateau the height of which is quantitatively proportional to the concentration of manganese.
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  • Kunio NISHIMURA, Tohru HIRAYAMA
    1968 Volume 17 Issue 12 Pages 562-568
    Published: December 15, 1968
    Released on J-STAGE: September 07, 2010
    JOURNAL FREE ACCESS
    The most of chemical methods for determination of mercury in gas camprises of collection of mercury from large volume of gas and of estimation of the amount of mercury collected.
    Dithizone method seems to have many merits for determination of small amount of mercury, but it is interfered by many kinds of impurities. Neutron activation analysis is suitable to the determination of mercury of low concentration because of the high sensitivity. For the development of the method of determination, the radioisotope tracer technique and activation analysis are very useful. Thus, we established the following method and analytical results were compared to those by dithizone method and gas detector tube method. In this method absorbent is saturated chlorine solution and absorption time is 2 hrs. After absorption, 4 ml of conc HNO3aq is added to the absorbent, and the mixture is concentrated to 8 ml, then it is sealed in the quartz capsule. Irradiation is carried out in HTR with neutron flux of 1.2×1011 n/cm2sec for s hrs. After cooling for loo hrs., samples are taken out from capsule and determined by the non-destructive method. The sensitivity of this method is 10-3mg/m3. However the sensitivity can be improved by use of irradiation with higher neutron fluxes and destructive methods.
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  • Tatsuro KAWASHIMA, Hisahito KAWAMURA
    1968 Volume 17 Issue 12 Pages 569-572
    Published: December 15, 1968
    Released on J-STAGE: September 07, 2010
    JOURNAL FREE ACCESS
    A 113mIn generator by the column of SnS2 precipitated on the anion exchange resin was prepared. This utilizes the isotopic exchange reaction between SnS2 and 113Sn solution. The long-lived parent 113Sn was loaded on the column and the short-lived daughter 113mIn was eluted out with 0.1-0.01M HCI. In each milking sequence, the leakage of 113Sn was found to be always of the order from 10-3 to 10-4 per cent of the original activity during the passage of 1l of the effluent through the column. The yield is about 20 per cent of the 113mIn on the column. The radiochemical impurities, 60Co and 114mIn present in 113Sn sample, are removed by this method.
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  • —Paints—
    Yoshiki WADACHI, Hideo YASUNAKA
    1968 Volume 17 Issue 12 Pages 573-577
    Published: December 15, 1968
    Released on J-STAGE: September 07, 2010
    JOURNAL FREE ACCESS
    Radioactive contamination protective paint is particularly desired to have quality of small contaminability and large decontaminability. Using 233UO2 (NO3) 2 acidic aqueous solution as radioactive contamination, it has been examined that kinds, manufacturing methods and components of paints and coating surface conditions influenced on their protective qualities.
    Results showed that some kinds of epoxy resin paints and vinyl chloride resin paints and also chlorinated rubber paint gave small contaminabilities and large decontaminabilities. After that, microscopic observation (168 magnifications) indicated these coating surfaces were compact and ordered surfaces, respectively.
    In addition, phenol resin paint and acryl resin paint gave comparatively good results.
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  • Eisaku TAJIMA, Hideo AKAIWA
    1968 Volume 17 Issue 12 Pages 578-580
    Published: December 15, 1968
    Released on J-STAGE: July 21, 2010
    JOURNAL FREE ACCESS
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  • Toshio ISHIYAMA
    1968 Volume 17 Issue 12 Pages 581-583
    Published: December 15, 1968
    Released on J-STAGE: July 21, 2010
    JOURNAL FREE ACCESS
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  • Naonori MATSUSAKA, Jiro INABA, Ryushi ICHIKAWA
    1968 Volume 17 Issue 12 Pages 584-587
    Published: December 15, 1968
    Released on J-STAGE: July 21, 2010
    JOURNAL FREE ACCESS
    Download PDF (316K)
  • [in Japanese]
    1968 Volume 17 Issue 12 Pages 588-598
    Published: December 15, 1968
    Released on J-STAGE: July 21, 2010
    JOURNAL FREE ACCESS
    Download PDF (1228K)
  • 1968 Volume 17 Issue 12 Pages A915-A480
    Published: December 15, 1968
    Released on J-STAGE: July 21, 2010
    JOURNAL FREE ACCESS
    Download PDF (3726K)
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