[en] A high-performance liquid chromatograph with a synchronized accumulating radioisotope detector was used to determine the turnover rate and pool size of tryptophan in rat. The specific radioactivity could be followed for three half-lives on the final slope of the specific radioactivity curve following intravenous administration of 15 muCi of carrier free tryptophan labeled with carbon-14. Remarkable individual differences were noted in turnover rate and in pool size among rats

[en] Measurement of specific radioactivity by a high-performance liquid chromatograph with a synchronized accumulating radioisotope detector was conducted. Accuracy of measurement for an authentic sample containing 0.2 nCi of tryptophan labeled with carbon-14 exceeded 95%. In the case of a plasma sample obtained 120 min following intravenous administration of 15 muCi of labeled tryptophan to a rat, the coefficient of variation was 7.0%

No abstract available

[en] Shikoku Electric Power Co., Inc. Ikata Nuclear Power Station has a regulation that workers must wear a half-face respirator (referred to in figure 1) to avoid internal exposure at the work place through coming into contact with radioactive substances. The washing of these respirators, currently performed in the Station, is done by manually rubbing them with a cloth penetrated with ethyl alcohol. The workers are therefore often required to lobar for a long time under rigorous conditions. Under these circumstances, experimental work has been conducted with the aim of developing washing apparatus suitable for the most commonly used type to respirator in the Station. (author)

[en] The infrared absorption spectra of eight isotopic ethylamine molecules, i.e., CH₃CH₂NH₂, CD₃CH₂NH₂, CH₃CD₂NH₂, CD₃CD₂NH₂, CH₃CH₂ND₂, CD₃CJ₂ND₂, CH₃CD₂ND₂, and CD₃CD₂ND₂, have been examined in the vapor phase in the 300--100 cm^-1 region. Several Q-branch peaks were observed for each isotopic species and assigned to the torsional oscillations of the methyl and amino groups of the trans and gauche isomers. The energy levels were calculated on the basis of a coupled two-top system. The analysis yielded a probable potential function for the internal rotation about the C--N bond of the form V (α) = (316.5/2)(1-cosα)-(11.3/2)(1-cos2α)+(713.7/2)(1-cos3α) -(25.0/2)(1-cos4α)+(25.0/2)(1-cos5α)-(3.7/2)(1-cos6α). The difference between the potential energy minima of the trans and gauche conformations is about 230 cm^-1, the trans being the more stable form. It has been concluded that the axis of internal rotation of the amino group does not coincide with the N--C bond but is along a line about 4.5degree from the N--C bond and in the plane bisecting the NHH triangle

[en] Ion cyclotron heating is efficiently used to produce and to heat plasma in magnetic mirrors. In plasma with rather low (less than 10¹⁸ m^-3) density the fast Alfven normal modes are generated both radially and longitudinally and plasma density affects essentially excitation of these modes. To heat plasma one uses efficiently the low Alfven waves. During the experiments one obtained ionic temperature exceeding 10 keV and it is confirmed via observation of fusion neutrons. Excitation of the Alfven normal modes is investigated in detail in the GAMMA 10 ambipolar trap

[en] We have examined the valence-band electronic structures of gold and silver in the same column in the periodic table with nominally filled d orbitals by means of a recently developed polarization-dependent hard x-ray photoemission. Contrary to common expectation, it is found that the 5d-orbital electrons contribute prominently to the conduction electrons in gold, while the conduction electrons in silver are to some extent free-electron-like with negligible 4d contribution, which could be related to the well-known fact that gold is more stable than silver in air. The 4d electron correlation effects are found to be essential for the conduction electron character in silver.

[en] The need for not only bulk sensitive but also extremely high resolution photoelectron spectroscopy for studying detailed electronic structures of strongly correlated electron systems is growing rapidly. Moreover, easy access to such a capability in one's own laboratory is desirable. Demonstrated here is the performance of a microwave excited rare gas (Xe, Kr, and Ar) lamp combined with ionic crystal filters (sapphire, CaF₂, and LiF), which can supply three strong lines near the photon energy of hnyu hν=8.4, 10.0, and 11.6 eV, with the hν resolution of better than 600 μeV for photoelectron spectroscopy. Its performance is demonstrated on some materials by means of both angle-integrated and angle-resolved measurements.

[en] Bulk valence band photoemission spectra of the Kondo semiconductor YbB₁₂ were measured with use of soft X-ray (hν=700 eV) at 20 and 200 K and the Kondo resonance behavior was confirmed. Sharp bulk Yb²⁺ 4f peaks are observed in the vicinity of Fermi level on fractured single crystals. From the spectra is estimated the Yb mean valence as 2.86±0.01 at 20 K and 2.91±0.01 at 200 K. The whole peaks of the Yb³⁺ 4f multiplets are found to shift by ∼30 meV toward higher binding energies with decreasing the temperature from 200 to 20 K. On the other hand, the shift of the peak energy position of the Yb²⁺ 4f spectra toward lower binding energies with decreasing the temperature is found to be less than 10 meV. The temperature dependence of the Yb 4f photoemission spectra is well explained by the non-crossing approximation (NCA) calculation based on the single impurity Anderson model (SIAM)

[en] We have fabricated Al₂O₃, LaAlO₃ (LAO), CaHfO₃ (CHO) and CaZrO₃ (CZO) thin films for the dielectric layers of field-effect transistors (FETs) by pulsed laser deposition (PLD). The films exhibited very smooth surfaces with root-mean-squares (rms) roughnesses of ∼1.3 A as evaluated by using atomic force microscopy (AFM). The breakdown electric fields of Al₂O₃, LAO, CHO and CZO films were 7, 6, 10 and 2 MV/cm, respectively. The magnitude of the leak current in each film was low enough to operate FET. We performed a comparative study of pentacene FET fabricated using these oxide dielectrics as gate insulators. High field-effect mobility of 1.4 cm²/V s and on/off current ratio of 10⁷ were obtained in the pentacene FET using LAO gate insulating film. Use of the LAO films as gate dielectrics has been found to suppress the hysteresis of pentacene FET operations. The LAO films are relevant to the dielectric layer of organic FETs