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181.
Silver in solution is determined in situ by the frequency change of a piezoelectric quartz crystal on electrodeposition on the electrode of the crystal. The electrolyte solution flows through a cell containing the platinum-plated electrode (cathode) of the quartz crystal, a coiled platinum-wire anode and a silver—silver(I) chloride reference electrode, and is electrolyzed at —0.2 V vs. . The frequency change is proportional to the silver concentration in the range 10-5–5 × 10-7 M after electrodeposition for 5 min, and in the range 10-8–10-9 M by recycling 20 ml of the solution over the electrodes for 3 h. 相似文献
182.
O. Hashimoto A. Sumi T. Nomura S. Nagamiya K. Nakai T. Yamazaki K. Miyano 《Nuclear Physics A》1974,218(1):180-188
The spin rotation of the 0.57 ms 7+state in202Tl has been observed by use of a pulsed magnetic field and the g-factor was determined to be 0.128 ± 0.006. The isomeric state was excited via the 204Hg(p, 3n)202Tl reaction with a 28 MeV pulsed beam of 1.2 ms interval. From the results, the main configuration of the 7+ state in202Tl is interpreted as (). 相似文献
183.
The simultaneous determination of alkaline-earth metal ions in acid solution was studied by modified normal pulse polarography. Well-defined waves were recorded for calcium, strontium and barium, but no limiting current was found for magnesium, because of its very negative reduction potential. The differential mode of this method gives peak-type polarograms and is useful for the simultaneous determination of species for which the half-wave potentials lie close together. The interference of dissolved oxygen was eliminated by the use of tetramethylammonium chloride as a supporting electrolyte. 相似文献
184.
M. Nomura 《Physics letters. [Part B]》1975,59(3):227-229
The binding energy of the hole state observed in neutron pick-up reactions is calculated in the framework of the shell model. Isospin symmetry and coupling between the hole and active protons in the same shell are taken into account. 相似文献
185.
In this note, inequalities between the distance degrees of distance degree regular graphs and to characterize the graphs when one of the equalities holds are proved. 相似文献
186.
Dan He Susana Behar Nakao Nomura Shigeru Sassa Henry W. Lim 《Photochemistry and photobiology》1995,61(6):656-661
To study porphyrin biosynthesis in human microvascular endothelial cells, HMEC-1 cells, a transformed human microvascular endothelial cell line, were incubated with 5-aminolevulinic acid (ALA), the precursor of endogenous porphyrins, and porphyrin accumulation was measured spectro-fluorometrically. The HMEC-1 cells accumulated porphyrin in a concentration-related and a time-dependent fashion. Protoporphyrin was the predominant porphyrin accumulated in the cells. The effect of light on protoporphyrin accumulation was evaluated by exposing the ALA-loaded HMEC-1 cells to ultraviolet-A (UVA) and blue light, followed by another incubation with ALA for 2–24 h. Enhancement of protoporphyrin accumulation in irradiated HMEC-1 cells was observed 2–24 h after irradiation, which was associated with a decrease in ferrochelatase protein and activity. Porphyrin accumulation from ALA after irradiation was significantly decreased when catalase (750–3000 U/mL, 29.3–44.3% suppression) or superoxide dismutase (270 U/mL, 36.4% suppression) was present during irradiation. These data demonstrate that HMEC-1 cells were capable of porphyrin biosynthesis, and that exposure of protoporphyrin-containing HMEC-1 cells to UVA and blue light, which includes the Soret band spectrum, decreased the ferrochelatase activity and its protein. These changes were mediated, at least in part, by reactive oxygen species. 相似文献
187.
188.
189.
H. Utsunomiya T. Nomura T. Inamura T. Sugitate T. Motobayashi 《Nuclear Physics A》1980,334(1):127-143
The α-particle emission following 14N-induced reactions on various heavy targets at 85–115 MeV has been studied. Cross sections of heavy residual nuclei produced after α-emission were measured in the case of the 209Bi target and were found to be close to the angle-integrated cross sections of α-particles, indicating that the α-emission mainly takes place in a binary process. The measured angular distributions of α-particles are pronouncedly forward-peaked, while the energy spectra are always characterized by the Maxwellian distribution even at forward angles and reproduced excellently by the statistical evaporation formula when nuclear temperature is treated as a free parameter. The resultant value of the temperature is high (4–6 MeV) at forward angles and decreases monotonically with increasing emission angles.The energy and angular distributions of protons, deuterons and tritons were also measured in the 181Ta + 14N reaction at 115 MeV. The results are similar to those of α-particles. In particular, nuclear temperatures turned out nearly equal to each other, being consistent with the hot-spot interpretation for the relevant preequilibrium light-particle emission. 相似文献
190.