Engineering topics

Yamazaki, Atsushi

Publications and source records attributed to Yamazaki, Atsushi.

3 records

DOE OSTI2017

Water Cleaning System for the Exhaust Pipe of HLW Glass Melter (LFCM) - 17180

Vitrification technology has been generally applied to stabilize High-Level Radioactive Waste (HLW) generated from spent fuel reprocessing. In Japan, Joule Heated Liquid Fed Ceramic Melter (LFCM) system is selected for HLW vitrification and the recent active test has been successfully demonstrated its stable operation. The higher reliability of off-gas treatment system (OGTS) which consists of wet scrubber, absorbers and filters connected to the LFCM is also important to ensure long term system operation. The OGTS removes radioactive gases, mists and dust generated by LFCM and maintains radioactive containments by keeping negative pressure inside. In the past active and inactive tests, it was observed that differential pressure in the exhaust pipe attached to LFCM gradually increased during continuous operation and some deposits were observed inside the off-gas pipe. So the cleaning operation needs to be improved and more frequent in order to avoid the exhaust pipe clogging. Therefore we investigated several cleaning systems and operational methods for the exhaust pipe of LFCM. As a result, we have successfully developed the modified water cleaning system. In this presentation we will introduce our water cleaning system. In addition, we will present the result of inactive mock-up tests for the visualization of this water cleaning system. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

DOE OSTI2016

RF synchronized short pulse laser ion source

A laser ion source that produces shortly bunched ion beam is proposed. In this ion source, ions are extracted immediately after the generation of laser plasma by an ultra-short pulse laser before its diffusion. The ions can be injected into radio frequency (RF) accelerating bucket of a subsequent accelerator. As a proof-of-principle experiment of the ion source, a RF resonator is prepared and H{sub 2} gas was ionized by a short pulse laser in the RF electric field in the resonator. As a result, bunched ions with 1.2 mA peak current and 5 ns pulse length were observed at the exit of RF resonator by a probe.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

NASA NTRS2014

Preliminary Results from a Coordinated Hisaki/Chandra/XMM-Newton Study of the Jovian Aurora and Io Plasma Torus

We present preliminary results from a coordinated Hisaki/Chandra/XMM-Newton observational campaign of the Jovian aurora and Io plasma torus. The data were taken over a three week period in April, 2014. Jupiter was observed continuously with Hisaki, six times with the Chandra/HRC instrument for roughly 12 hours per observation, and twice by XMM-Newton. The goal of this observational campaign was to understand how energy and matter are exchanged between the Jovian aurora, the IPT, and the Solar wind. X-ray observations provide key diagnostics on highly stripped ions and keV electrons in the Jovian magnetosphere. We use the temporal, spatial, and spectral capabilities of the three instruments to search for correlated variability between the Solar wind, the EUV-emitting plasma of the IPT and UV aurora, and the ions responsible for the X-ray aurora. Preliminary analysis suggests a strong 45 min periodicity in the EUV emission from the electron aurora. There is some evidence for complex variability of the X-ray auroras on scales of tens of minutes. There is also clear morphological changes in the X-ray aurora that do not appear to be correlated with either variations in the IPT or Solar wind.

Kraft, Ralph↗