Removal efficiency of radioactive cesium and iodine ions by a flow-type apparatus designed for electrochemically reduced water production.

The Fukushima Daiichi Nuclear Power Plant accident on March 11, 2011 attracted people's attention, with anxiety over possible radiation hazards. Immediate and long-term concerns are around protection from external and internal exposure by the liberated radionuclides. In particular, residents living in the affected regions are most concerned about ingesting contaminated foodstuffs, including drinking water. Efficient removal of radionuclides from rainwater and drinking water has been reported using several pot-type filtration devices. A currently used flow-type test apparatus is expected to simultaneously provide radionuclide elimination prior to ingestion and protection from internal exposure by accidental ingestion of radionuclides through the use of a micro-carbon carboxymethyl cartridge unit and an electrochemically reduced water production unit, respectively. However, the removability of radionuclides from contaminated tap water has not been tested to date. Thus, the current research was undertaken to assess the capability of the apparatus to remove radionuclides from artificially contaminated tap water. The results presented here demonstrate that the apparatus can reduce radioactivity levels to below the detection limit in applied tap water containing either 300 Bq/kg of 137Cs or 150 Bq/kg of 125I. The apparatus had a removal efficiency of over 90% for all concentration ranges of radio-cesium and -iodine tested. The results showing efficient radionuclide removability, together with previous studies on molecular hydrogen and platinum nanoparticles as reactive oxygen species scavengers, strongly suggest that the test apparatus has the potential to offer maximum safety against radionuclide-contaminated foodstuffs, including drinking water

Detecting low usability web pages using quantitative data of users' behavior

ICSE '06 : the 28th international conference on Software engineering, May 20-28, 2006, Shanghai, ChinaThe purpose of this research is to detect low usability web pages from the behavior of users, such as browsing time, mouse movement and eye movement. We experimented to investigate the relation between the quantitative data viewing behavior of users and web usability evaluation by subjects. We analyzed the data to detect low usability web pages using discriminant analysis. Low usability web pages, 94.4% (17pages / 18pages = detectable pages / low usability pages) were detectable from the moving speed of gazing points and the amount of wheel rolling of a mouse. Moreover, this detection reduced the number of web pages which should be evaluated by half (46% = 89 pages / 192 pages = detected pages / all pages)