Different Crystal Chemistries of the 117Cd→117In and 111mCd→111Cd Probes in LiNbO3 and LiTaO3 Studied by Time-Differential Perturbed-Angular-Correlation Technique

金沢大学理学部The temperature dependences of the nuclear-electric-quadrupole frequency vQ of 117In doped in LiTaO3 (TC5938 K) and Li12xInx/3TaO3 with x50.2 (TC5818 K) show that the order-disorder of the Li ions is not the driving mechanism for the ferroelectric instability in LiNbO3 and LiTaO3 systems, and imply that the oxygen order-disorder is the driving mechanism. The significantly different temperature dependences of vQ of 111Cd in these materials compared, to those of 117In, demonstrate that this order-disorder is of dynamic character

THEORY OF PION INDUCED NUCLEON REMOVAL IN THE (3,3) RESONANCE REGION; MULTINUCLEON REMOVAL REACTIONS IN THE INTERACTION OF IODINE-127 WITH 60-350 MEV PIONS

A Benioff-type calculation has been performed to calculate the ((pi)(\u27(+OR-)),(pi)N) reaction cross sections in the (3,3) resonance region (100-300 MeV) for (\u2712)C, (\u2725)Mg, (\u27127)I, and (\u27197)Au, treating the nucleon charge exchange probability P as an adjustable parameter. For (\u2712)C P has also been estimated using the free particle-free particle picture. Nucleon charge exchange appears to be needed to explain the anomaly seen in the cross section ratio for light nuclei, whereas it is unimportant for heavy nuclei as the consequence of two effects, i.e. nuclear shell effect and size effect. An experiment has been performed to measure the (\u27127)I((pi)(\u27(+OR-)),X)(\u27127-x)I reaction cross sections in the (3,3) resonance region (60-350 MeV), using activation techniques. The results obtained have been compared with the ISOBAR-DFF calculation. Pion inelastic scattering followed by evaporation is the dominant mechanism except for (\u27126)I, i.e. single-nucleon removal, for which the importance of this mechanism and that of direct knockout are comparable. The mass loss in the evaporation process appears to be more significant than that in the cascade process. The cross sections due to (pi)(\u27+) absorption have been estimated phenomenologically. Pion absorption is significant only for the formation of low mass iodine isotopes at low energies. the ISOBAR-DFF code reproduces the overall features in the reactions studied. However, this code generally underestimates the cross sections and may overestimate those associated with pion absorption

Studies of interaction between He and elements with mass number 140 in Fe by time-differential perturbed-angular-correlation measurements

Room-temperature time-differential perturbed-angular-correlation (TDPAC) spectra of [140]Ce arising through [140]Ba-[140]La from [140]Cs in He-doped Fe, unannealed and annealed in vacuum at various temperatures, were obtained in order to examine whether Ce (or rather, La and Ba) and He form complexes having a definite geometrical structure in Fe, as suggested by first-principles density-functional theory calculations. No clear signal of such complexes was observed in the TDPAC spectra. However, the TDPAC spectra indicate that Ce and He form complexes having a variety of geometrical structures. Comparison with reported TDPAC results on [111]Cd arising from [111]In in He-doped stainless steel shows that the parent atoms (La and Ba) of [140]Ce trap He atoms more efficiently than In atoms do, indicating stronger bonding of He to the former atoms, while different from the present case, [111]Cd (In)–He complexes form a unique geometrical structure

Hyperfine Interaction of 140 Ce(← 140 La) in CaB 6

A 140 La(I π = 3 − , T 1/2 = 40.3 h)-doped layer has been produced in CaB 6 by means of radioactive isotope (RI) beam technique: 140 Cs(I π = 1 − , T 1/2 = 63.7 s) was implanted into CaB 6 and the radioactive equilibrium of 140 Ba-140 La was achieved. The concentration of La in CaB 6 was La/Ca ∼ 0.001 and ∼0.005. Obtained TDPAC spectra of the 2083 keV level of 140 Ce (I π = 4 + , T 1/2 = 3.4 ns, µ = +4.35±0.10µ N ) followed by the β decay of 140 La showed the existence of hyperfine magnetic fields: B hyp = −15.0±0.5 T and −1.00±0.15 T for La/Ca ∼ 0.001 and B hyp = −1.51 ± 0.12 T for La/Ca ∼ 0.005

Radiochemical Study on the Mechanism of Target Fragmentation of Cu, Nb, Pr and Au Targets Induced by 12C and 40Ar Projectiles

A thick-target thick-catcher experiment was performed to measure the formation cross sections and recoil momenta of products from target fragmentation of Cu, Nb, Pr, and Au by using gamma-ray spectrometry. Bombardments of C ions (180, 290, and 400 MeV/u) and Ar ions (290 and 650 MeV/u) were performed at the HIMAC facility in Japan. The results were discussed in comparison with systematics of fragmentation and used to deduce the prefragments in fragmentation process of the measured systems

Endoplasmic reticulum resident, immunoglobulin joining chain, can be secreted by perturbation of the calcium concentration in the endoplasmic reticulum

We established a transient human joining (J)-chain gene expression system in the baby hamster kidney (BHK) cell. The J-chain was detected as a 29-kDa single band on Western blotting. Immunofluorescent staining of the transfectant revealed an exclusive localization of the J-chain in the endoplasmic reticulum (ER). Intracellular transport experiment revealed that incubating conditions favorable for vesicular stomatitis virus glycoprotein (VSV-G) transport did not allow the J-chain to exit from the ER. Analysis of glycosylation status of the J-chain in the transfectant was examined by tunicamycin treatment, endoglycosidase H digestion, and also by treatment with brefeldin A. It was found that an N-glycosylation consensus site of the J-chain was functional, and intracellular J-chain was endoglycosidase H sensitive. These results indicate that, in the absence of any immunoglobulin molecules, J-chain localizes exclusively in the ER. We also tested whether the J-chain could be exported from the ER by perturbing the Call concentration in the ER. Cultivation of the J-chain transfectant in the presence of ionomycin resulted in the time-dependent secretion of the J-chain. The secreted J-chain was modified by the Golgi resident glycosylation enzymes, indicating that the secreted J-chain passed through the normal exocytic pathway