-
Isao SUGAI, Seisaku TAKAKU, Takeo HASEGAWA
1978 Volume 27 Issue 6 Pages
295-299
Published: June 15, 1978
Released on J-STAGE: September 07, 2010
JOURNAL
FREE ACCESS
Several kinds of materials were examined for the usefulness as releasing agents in the preparation of various thin self-supporting target films for use in nuclear reaction experiments. NaCl, BaCl
2, KCl, CsI,
Teepol, glucose, KIO
3,
mica, nitrocellulose or Formvar was deposited onto glass plates as the release agent by vacuum evaporation or dipping method. The obtained target film was tested on impurities from the release agent by using nuclear reactions. The relative effectiveness of each release agent was also considered from ease in the stripping of target films.
View full abstract
-
Nagao IKEDA, Naruto TAKAHASHI
1978 Volume 27 Issue 6 Pages
300-305
Published: June 15, 1978
Released on J-STAGE: September 07, 2010
JOURNAL
FREE ACCESS
Eleven rare earth elements (lanthanum, cerium, neodymium, samarium, europium, gadolinium, terbium, holmium, thulium, ytterbium and lutetium) in hot spring waters and sinter deposits in the Nasu area were determined by the neutron activation method. The rare earth elements in hot spring water were pre-concentrated in ferric hydroxide precipitate and neutronirradiated. The rare earth elements were chemically separated into lighter and heavier groups and the activity of each group was measured with a Ge (Li) detector. Distribution of the rare earth elements between the hot spring water and the sinter deposit was also discussed.
View full abstract
-
Masakatsu TEZUKA, Shoji OKADA, Osamu TAMEMASA
1978 Volume 27 Issue 6 Pages
306-310
Published: June 15, 1978
Released on J-STAGE: September 07, 2010
JOURNAL
FREE ACCESS
Recently, a considerable amount of phthalic acid esters (PAE), the most widely utilized plasticizer, has been released into and polluted the environment. Since their toxicity and teratogenicity, although fairly low, to experimental animals have recently been shown, the removal of them from the environment, especially from the drinking water, is desirable. As an attempt for the removal, the radiolytic degradation of 7-14C
-di-n-butyl phthalate (
14C-
DBP)
in water was investigated at several pHs. Approximately 50% of 14C-
DBP (
1 ppm aqueous solution)
was decomposed by 60Co γ-
irradiation to a dose of 3 × 104 rad at pH 7 and the main product was mono-n-butyl phthalate (MBP) . At pHs 3 and 11 14C-
DBP was more easily radiolyzed and converted to ether-soluble compounds other than MBP or phthalic acid (PA) . By irradiation to 106 rad 14C
-DBP as well as 14C-MBP and 14C-
PA, at pH value tested, was almost completely decomposed to volatile or water-soluble substances of possibly low molecular weight. These findings suggest that the γ-irradiation is effective to make the PAE-polluted water clean.
View full abstract
-
Takeo HASEGAWA, Hiroshi HASHIBA, Kiyoshi AKAGI, Tatsuo FUJINO, Akitosh ...
1978 Volume 27 Issue 6 Pages
311-317
Published: June 15, 1978
Released on J-STAGE: September 07, 2010
JOURNAL
FREE ACCESS
High energy collimators in use today are limited with respect to resolution and efficiency. The multiple pinhole coded aperture (hereafter abbreviated as MPCA) is a method being considered to improve the above. In our study we conducted basic experiments with an MPCA using an Anger-type γ-camera. Using this method, we were able to perform radioisotope imaging and radioisotope tomo graphic effect. We have studied the resolution, detection efficiency, and tomo graphic effects of the MPCA. We found that, in the MPCA, detection efficiency is proportional to the number of pinholes and resolution is dependent upon the pinhole diameter. This tomographic effect is of the same principle as the stretching-type tomography, images on both side of the desired image appearing as noise images, affecting the depth resolution. Using an MPCA with a pinhole diameter of 3 mm and 3 pinholes positioned in an equilateral triangular pattern measuring 7.8 cm on each side, we attained a depth resolution of 3 cm. Because the MPCA method involves complicated image processing, the resulting image contains a factor of 2n-2 (where n is the number of pinhole) of noise, affecting the depth resolution.
View full abstract
-
Isao UCHIDA, Yoshio ONAI, Teizo TOMARU, Toraji IRIFUNE, Makoto KAKEGAW ...
1978 Volume 27 Issue 6 Pages
318-323
Published: June 15, 1978
Released on J-STAGE: September 07, 2010
JOURNAL
FREE ACCESS
Collimator artifacts may be present within the images produced by collimators whose septal width approaches the inherent resolution of the gamma-camera system. As the inherent resolution of the gamma-camera is improved, collimator artifacts become more prominent. The purpose of this study is to eliminate collimator artifacts from gamma-camera images. To eliminate the septum effect produced by high-energy parallel-hole collimators with thick septa, the following method was used: X and Y signals from the detector are made to ride on the triangular waves changing periodically, and resultant position signals obtained by this processing are applied to the corresponding deflection circuits in the CRT display. The oscillation amplitude of processed position signals can be regulated by the frequency and amplitude of the triangular waves. Regulation of the oscillation amplitude of position signals, which would produce maximum reduction of collimator artifacts, was to approach the spatial frequency responses of the overall processed line spread functions obtained experimantally to those of the Gaussian functions with FWHM equal to the geometric resolution calculated from the equation given by Gerber and Miller. In images of a pancreas phantom containing 131I,
collimator artifacts were clearly seen in the unprocessed case, but were eliminated in the processed case.
View full abstract
-
—Synthesis of S-n-Butyl S'-p-tert-Butylbenzyl-14C N-3-Pyridyldithiocarbonimidate (Denmert®) —
Akira YOSHITAKE, Takeshi KAMADA, Iwao NAKATSUKA, Kunio MIYAKE
1978 Volume 27 Issue 6 Pages
324-325
Published: June 15, 1978
Released on J-STAGE: July 21, 2010
JOURNAL
FREE ACCESS
-
Ryuji ONISHI, Akira MATSUMOTO, Yasuo KAINO, Hideyuki KOCHI, Kazuo ITO, ...
1978 Volume 27 Issue 6 Pages
326-329
Published: June 15, 1978
Released on J-STAGE: July 21, 2010
JOURNAL
FREE ACCESS
-
Yasuhito SASAKI, Yumi SHOJI, Takako TAKAHASHI, Humiko ASABA, Tokuichi ...
1978 Volume 27 Issue 6 Pages
330-333
Published: June 15, 1978
Released on J-STAGE: July 21, 2010
JOURNAL
FREE ACCESS
-
Isamu MIYAMORI, Kung Su KIM, Ikuo YAMAMOTO, Kenzo UCHIDA, Shinpei MORI ...
1978 Volume 27 Issue 6 Pages
334-337
Published: June 15, 1978
Released on J-STAGE: July 21, 2010
JOURNAL
FREE ACCESS
-
Seikoh NISHIDA, Shigeichi MATSUMURA, Masaharu HORINO, Hideki OYAMA, At ...
1978 Volume 27 Issue 6 Pages
338-341
Published: June 15, 1978
Released on J-STAGE: July 21, 2010
JOURNAL
FREE ACCESS
-
Tetsuo UETE, Keiko AWA
1978 Volume 27 Issue 6 Pages
342-344
Published: June 15, 1978
Released on J-STAGE: July 21, 2010
JOURNAL
FREE ACCESS
-
Masayuki MAEDA
1978 Volume 27 Issue 6 Pages
345-347
Published: June 15, 1978
Released on J-STAGE: July 21, 2010
JOURNAL
FREE ACCESS
-
Toshimasa KIMURA, Tatsuji HAMADA
1978 Volume 27 Issue 6 Pages
348-349
Published: June 15, 1978
Released on J-STAGE: July 21, 2010
JOURNAL
FREE ACCESS
-
Hideo UEDA
1978 Volume 27 Issue 6 Pages
350-357
Published: June 15, 1978
Released on J-STAGE: July 21, 2010
JOURNAL
FREE ACCESS
-
(I) Preface to Lectures
Sueo ASO
1978 Volume 27 Issue 6 Pages
358
Published: June 15, 1978
Released on J-STAGE: July 21, 2010
JOURNAL
FREE ACCESS
-
Yoshio YAMADA
1978 Volume 27 Issue 6 Pages
359-365
Published: June 15, 1978
Released on J-STAGE: July 21, 2010
JOURNAL
FREE ACCESS
-
1978 Volume 27 Issue 6 Pages
A1827-A1336
Published: June 15, 1978
Released on J-STAGE: July 21, 2010
JOURNAL
FREE ACCESS