[en] A short-period undulator using a superconducting magnet is proposed. This undulator has been designed to install in the KEK-Photon Factory 2.5-GeV or 6.5-GeV storage ring. The idea of a staggered wiggler, developed in Stanford university, is used in this undulator. The target of the period and K value of the undulator are set to be 1 cm and 1, respectively. We can obtain monochromatic photons with an energy of ∼ 5keV or ∼ 40 keV by using the undulator. (author)

No abstract available

[en] An isotope exchange method of analysis is proposed, which can be applied to exchange systems in which the rate of the exchange reaction is rather slow but measurable. The validity of the principle of the method is verified experimentally with several exchange systems of KI and alkyl, alkylene or benzyl iodide. The iodine content of the organic iodine compounds can be determined with an error of +-4%. The method is easier and simpler compared with the conventional methods. In addition, some information on bonding of the iodine atom(s) in the compound can be also given from the rate of isotope exchange. (T.G.)

[en] Uranium in several human tissues (lung, liver, kidney, muscle, spleen, heart, cerebrum and bones) from Japanese in the Tokyo area was determined by the fission track method. The average U content was the highest in lung with 1.70 ppb wet, and decreased in the order of lung greater than bones greater than heart and muscle greater than kidney greater than liver and spleen, showing markedly different tendencies from the description in the 1982 UNSCEAR Report (UNSCEAR82). Correlations were observed between U content in lung and in other tissues. These data suggest that the contribution of inhalation of U to its total intake is not negligible. The total body burden of U for the ICRP Reference Man (ICRP74) was estimated to be about 40 micrograms, which is rather small compared with the average normal burden of 90 micrograms currently accepted by the International Commission on Radiological Protection (ICRP79)

[en] We report a new method of measuring the absolute ionization efficiency of an ion source, which is independent of gas flow rate fed to an ionizer and of detection efficiency of the resulting ions. The method is based on the fact that when a pulsed alternate potential is applied between the ionizer and an electrode set outside near its exit hole, ions stored inside the ionizer while the potential is repulsive for the ions are flushed out as soon as it becomes attractive. It is shown that when the duty factor and repetition rate of the applied potential are properly chosen, the magnitude of this bunching effect can simply be expressed only by the ionization efficiency. Since its magnitude can quickly be evaluated, for example, by observing the time dependence of the bunched ion current in an oscilloscope, it provides a simple and reliable way for on-line diagnostics of the source. (author)

[en] The nuclear levels above the p + ¹⁹Ne threshold in ²⁰Na, which are critical for the breakout problem from the hot CNO cycle and the following heavy-element synthesis, have been extensively studied by the (³He,t) and (p,n) reactions on ²⁰Ne. Several new spin-parity assignments have been made. Specifically, the first excited state above the threshold has been identified to be 1⁺ at 2.637 MeV (0.438 MeV above the threshold), indicating this state to be the s-wave resonant state in the p + ¹⁹Ne scattering. The stellar reaction rate of the ¹⁹Ne(p,γ) process is evaluated for the first time based on the experimental results of ²⁰Na, and the result is more than two orders of magnitude larger than the previous theoretical predictions. The onset temperature of the flow-out from the hot CNO cycle to heavier elements is estimated to be as low as about 2.3 x 10⁸ K, suggesting that the flow-out via this process is an explanation for the strong enhancement in Ne and heavier elements in nova observations. (author)

[en] Recent experimental studies on ²⁰Na and ²¹Mg and the implication to the onset of the rapid-proton process in stellar sites are discussed. A plan of the nuclear reaction studies with using radioactive nuclear beams is also presented. (author)

[en] Quasi-molecular states near and below the threshold of the molecular configuration in sd-shell nuclei are discussed using recent experimental data with particle-gamma coincidence method and particle-particle coincidence method. Possible quasi-molecular states have been identified in ²⁴Mg as well as in ²⁸Si and ³²S. The important role of quasi-molecular states are discussed, specifically for the shape evolution of nuclei as a function of excitation energy and angular momentum. (author)

[en] The substoichiometric method is applied to simple radiometric analysis. Two methods - the standard reagent method and the standard sample method - are proposed. The validity of the principle of the methods is verified experimentally in the determination of silver by the precipitation method, or of zinc by the ion-exchange or solvent-extraction method. The proposed methods are simple and rapid compared with the conventional superstoichiometric method. (author)

[en] Some results of the assembling, electrical tests and performance of the screw pinch device TPE-2, with a non-circular cross-section are presented. The main object of the experiments is to attain the long confinement of the fat and high beta plasma produced by the fast shock heating in the screw pinch mode with a force free current and the high beta tokamak mode. plasma, we chose the fat torus and non-circular The another object is to develop the high voltage engineering with the aim of a high beta pulsed reactor