Jun Hu

Hirosaki University · Department of Radiation Pyhsics

Radiation exposure due to radon contributes most of the ionizing radiation exposure to people among natural radiation sources. This research measured the ²²²Rn, ²²⁰Rn by the RADUET and their progeny concentrations by the improved deposition based ²²²Rn and ²²⁰Rn progeny monitor, and the contribution of outdoor PM2.5 concentrations to indoors by a m...

For the first time, using ICP-MS/MS, the 234U, 235U, 236U, and 238U in the sediment samples from coastal region, Bangladesh, were measured as 5.13–5.48, 0.234–0.252, (2.70–4.59) × 10–5, and 4.92–5.31 Bq kg−1, and the 236U/238U atom ratios were (2.87–4.57) × 10–8, indicating the predominate influence of global fallout on 236U. For the rock samples f...

For the first time, using ICP-MS/MS, the 234U, 235U, 236U, and 238U in the sediment samples from coastal region, Bangladesh, were measured as 5.13–5.48, 0.234–0.252, (2.70–4.59) × 10–5, and 4.92–5.31 Bq kg−1, and the 236U/238U atom ratios were (2.87–4.57) × 10–8, indicating the predominate influence of global fallout on 236U. For the rock samples f...

This study aimed at understanding the atmospheric concentrations of 210Pb and major ions in aerosols in Qingdao, China, including their seasonal variations and relationships with weather data and to identify the sources of atmospheric sulfur as a part of the Japan-China joint project, “Aeolian Dust Experiment on Climate Impact (ADEC)”. The sampling...

An improved passive CR-39-based direct 222Rn/220Rn progeny detector with 3 detection channels was designed and tested in this study to measure and calculate equilibrium equivalent concentration (EEC) of both 222Rn and 220Rn without the equilibrium factor. A theoretical model was established to calculate the EEC with optimization. Subsequently, an e...

The U-series and Pu isotope signatures in the environment have emerged as important tools for promoting geochemical studies. To enhance the understanding of U and Pu sources and behaviours in river systems, this study examined ²³⁴U, ²³⁵U, ²³⁶U, ²³⁸U and ²³⁹Pu, ²⁴⁰Pu isotopes in surface sediments collected from the Yangtze River catchment and estuar...

The deposition-based direct indoor 222Rn and 220Rn progeny measurement techniques are mostly affected by the indoor environmental conditions, such as the ventilation, concentration of condensation nuclei, and reactions with the structure and its furnishings. In this study, a theoretical model of a direct 222Rn and 220Rn progeny monitor based on all...

222 Rn, 220 Rn and their short-lived progenies are well known radioactive indoor pollutants, identified as the leading environmental cause of lung cancer next to smoking. Apart from the conventional measurement methods, numerical modeling methods are developed to simulate their physical and decay processes in 222 Rn and 220 Rn's life cycle, estimat...

During the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, large amounts of radioactive materials were released into the environment. Among them, a large proportion of the radionuclides, such as Cs, entered into the environment as radioactive microparticles (RMs). In recent years, the characterization of RMs based on synchrotron radiation (...

This review illustrated the radiation effects on the environment in Japan, the improvements and applications of source identification by using radioisotope tracer, the resulted challenge on the environment and radiation dose estimation due to the released radioactive microparticles, and the regulations and current situation of food safety in Japan,...

Almost 8 years after the Japanese Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, data for ²³⁶ U and ²³⁶ U/ ²³⁸ U have mainly remained limited to only a few heavily contaminated samples. In the present study, activities of ²³⁶ U, ¹³⁴ Cs, and ¹³⁷ Cs, along with ²³⁴ U, ²³⁵ U, ²³⁸ U, in 15 river bank soil and 10 river sediment samples, were me...

During the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, large amounts of radioactive materials were released into the environment. Among them, a large proportion of the radionuclides, such as Cs, entered into the environment as radioactive microparticles (RMs). In recent years, the characterization of RMs based on synchrotron radiation (...

The Laoguanhe River is a major tributary of the Danjiang River, which is the source water for the Danjiangkou Reservoir (i.e., the source reservoir for the middle route of the South-to-North Water Diversion Project in China). This study was intended to provide scientific decision support to help manage the water environment in the Laoguanhe River a...

222 Rn,220Rn and their short-lived progenies are well known radioactive indoor pollutants, identified as the leading environmental cause of lung cancer next to smoking. Apart from the conventional measurement methods, numerical modeling methods are developed to simulate their physical and decay processes in222Rn and220Rn's life cycle, estimate thei...

For this paper, according to the statistics of water resources amounts and utilization needs, we carried out a water resources security preliminary evaluation from the following points of view: water consumption balance analysis, available water resources analysis, supply-demand water resources balance analysis, and overall water resources security...

Based on monthly mean temperature and precipitation data for 53 years, from 1957 to 2009, recorded at the Zhangweinan River Basin and five main meteorological stations around it, the non-parametric Mann-Kendall trend test method and cumulative anomaly methods were adopted to analyze the long-term trends here of such key meteorological elements as a...

As an idle place of cage culturing, Qiandao Lake has been suffering from a series of problems because of the cage culturing these recent years, which affected the water environment in a certain extent. In this paper, we analyzed the exact water environment affection caused by the cage culturing in Qiandao Lake based on the methods of contrastive de...

The changing characteristics of landscape patterns in Zoige County, from 1986 to 2005 were investigated using time-series high-quality Land sat Thematic Mapper(TM) images. The article first carried out the images data processing using the eCognition software, and then used the GIS and FRAGSTAT software to calculate the Land Use/Cover Change (LUCC)...