ABSTRACT
A new beam profile monitoring system for the small X-ray beam exiting from the SPring-8 front-end was developed and tested at BL13XU. This system is intended as a screen monitor and also as a position monitor even at beam currents of 100 mA by using photoluminescence of a chemical vapor deposition-grown diamond film. To cope with the challenge that the spatial distribution of the photoluminescence in the vertical direction is too flat to detect the beam centroid within a limited narrow aperture, a filter was installed that absorbs the fundamental harmonic concentrated in the beam center, which resulted in "de-flattening" of the vertical distribution. For the measurement, the filter crossed the photon beam vertically at high speed to withstand the intense heat flux of the undulator pink-beam. A transient thermal analysis, which can simulate the movement of the irradiation position with time, was conducted to determine the appropriate configuration and the required moving speed of the filter to avoid accidental melting. In a demonstration experiment, the vertically separated beam profile could be successfully observed for a 0.8 × 0.8 mm(2) beam shaped by an XY slit and with a fundamental energy of 18.48 keV. The vertical beam centroid could be detected with a resolution of less than 0.1 mm.
ABSTRACT
Following a successful study on the prediction of fatigue life of high-heat-load components made of Glidcop, the thermal limitation of oxygen-free copper (OFC), which is used more commonly than Glidcop, has been studied. In addition to its general mechanical properties, the low-cycle-fatigue (LCF) and creep properties of OFC were investigated in detail and compared with those of Glidcop. The breaking mode of OFC, which was observed to be completely different from that of Glidcop in a fatigue fracture experiment, clarified the importance of considering the creep-fatigue interaction. An additional LCF test with compressive strain holding was conducted so that the creep-fatigue life diagram for out-of-phase thermal fatigue could be obtained on the basis of the strain-range partitioning method. The life predicted from elasto-plastic creep analysis agreed well with that determined from the void ratio estimated in the fatigue fracture experiment.
ABSTRACT
A procedure to predict the fatigue fracture life of high-heat-load components made of GlidCop has been successfully established. This method is based upon the Manson-Coffin equation with a cumulative linear damage law. This prediction was achieved by consolidating the results of experiments and analyses, and considered the effects of environment and creep. A low-cycle-fatigue test for GlidCop was conducted so that environment-dependent Delta(t)-N(f) diagrams for any temperature could be prepared. A special test piece was designed to concentrate the strain in a central area locally, resulting in the low-cycle-fatigue fracture. The experiments were carried out by repeatedly irradiating a test piece with an electron beam. The results of the experiment confirmed that the observed fatigue life was within a factor of two when compared with the predicted fatigue life, yet located on the safer side.
ABSTRACT
The thermal contact conductance (TCC) of a real front-end component at SPring-8 has been quantitatively estimated by comparing the results of experiments with those of finite-element analyses. In this paper one of the methods of predicting the TCC of a real instrument is presented. A metal filter assembly, which is an indirect-cooling instrument, was selected for the estimation of the TCC. The temperature of the metal filter assembly for the maximum heat load of synchrotron radiation was calculated from the TCC that is expected under normal conditions. This study contributes towards the ongoing research program being conducted to investigate the real thermal limitation of all front-end high-heat-load components.
ABSTRACT
Various processed foods and beverages have been manufactured using deep seawater (DSW), desalted DSW (dDSW), and concentrated DSW in Japan. To confirm the safety of dDSW, we investigated hematologic and blood chemical effects of dDSW in mice. The dDSW and desalted surface seawater (dSSW) were diluted to 6.7%, 10%, and 20% with purified water. BALB/c mice were housed for 12 weeks, and administered the diluted dDSW, dSSW, or purified water as a control during the period. The results for dDSW were compared with those for dSSW and purified water. None of the groups of mice showed any clear abnormal growth or behavior; neither did any show signs of illness nor a single case of death during the 12 weeks study. We found no significant differences between the dDSW and control groups in terms of red blood cell count, hemoglobin, hematocrit, white blood cell count, and neutrophil counts, whereas white blood cell and lymphocyte counts were significantly higher in the 10% dSSW group at the end of 4 and 12 weeks than those in the control group. A significantly higher triglyceride level was detected only in the 6.7% dSSW group. Our results show no evidence of acute or subacute effects of diluted dDSW. Effects of diluted dDSW on hematologic and blood chemical values in mice are thought to be similar to those of purified water. This finding suggests that dDSW is as safe as purified water for drinking water.
