Interfacial distribution of Nafion ionomer thin films on nitrogen-modified carbon surfaces

Yoshimune, Wataru*; Kikkawa, Nobuaki*; Yoneyama, Hiroaki*; Takahashi, Naoko*; Minami, Saori*; Akimoto, Yusuke*; Mitsuoka, Takuya*; Kawaura, Hiroyuki*; Harada, Masashi*; Yamada, Norifumi*; et al.

ACS Applied Materials & Interfaces, 14(48), p.53744 - 53754, 2022/11

https://doi.org/10.1021/acsami.2c14574

Characteristics in trace elements compositions of tephras (B-Tm and To-a) for identification tools

Nara, Fumiko*; Yokoyama, Tatsunori; Yamasaki, Shinichi*; Minami, Masayo*; Asahara, Yoshihiro*; Watanabe, Takahiro; Yamada, Kazuyoshi*; Tsuchiya, Noriyoshi*; Yasuda, Yoshinori*

Geochemical Journal, 55(3), p.117 - 133, 2021/00

https://doi.org/10.2343/geochemj.2.0619

The absolute date of the Millennium Eruption (ME) of Changbaishan Volcano is widely recognized as AD 946. The Baegdosan-Tomakomai (B-Tm) tephra dispersed during the ME is a robust-age key bed. In order to identify the tephra, refractive index and major-element compositions of volcanic glass shards are conventionally used. However, trace-element analysis has been rarely carried out, especially for rare-earth elements (REEs) and for tephra layer bulk sediments. Here we present the datasets of major- and trace-element compositions datasets for the glass shards and bulk sediments of the B-Tm and Towada caldera eruptions (To-a) tephra deposits from the Lake Ogawara sediment core, Tohoku region, northern Japan. The depth profiles of the major and trace elements show the significant peaks for the KO and some trace elements (Zn, Rb, Zr, Nb, Sn, Y, La, Ce, Nd, Th, and U) at the B-Tm tephra layer in the Lake Ogawara sediment core, but no peaks of these elements at the To-a tephra layer. High concentrations of the trace elements in the B-Tm tephra layer were observed in individual glass shards as well as in the bulk sediment. These concentrations are highlighted by the elemental abundance pattern normalized by the crustal abundance. The elemental pattern in individual glass shards from other Japanese tephras showed significant differences from those of the B-Tm tephra, especially in REEs compositions. The trace-element compositions of the glass shards and bulk sediment show strong advantages for distinguishing the B-Tm tephra from other Japanese tephras.

Development of the Monju core safety analysis numerical models by Super-COPD code

Yamada, Fumiaki; Minami, Masaki*

JAEA-Data/Code 2010-023, 79 Pages, 2010/12

JAEA-Data-Code-2010-023.pdf:3.27MB

Japan Atomic Energy Agency constructed a computational model for safety analysis of Monju reactor core to be built into a modularized plant dynamics analysis code Super-COPD code, for the purpose of heat removal capability evaluation at the in total 21 defined transients in the annex to the construction permit application. The applicability of this model to core heat removal capability evaluation has been estimated by back to back result comparisons of the constituent models with conventionally applied codes and by application of the unified model.

Development of "FBR plant engineering system"

Minami, Masaki*; Sakata, Hideaki; Yoshikawa, Shinji; Yamada, Fumiaki

JNC TN4410 2005-001, 123 Pages, 2005/03

JNC-TN4410-2005-001.pdf:6.81MB

A software system for straightforward and quick conceptual studies and technical evaluations of fast breeder reactor plants has been developed, mainly targeting the Japanese Demonstration Fast Breeder Reactor Monju. The studies and evaluations by this system used to be limited within steady and nominal conditions, excluding influences by changing specification values in accidental conditions. In this fiscal year, a new software component has been included in the system for simplified evaluation of transient characteristics, which is an essential for complete design of an FBR plant. This new evaluation function enabled to detect specifications to vary over acceptable range in transient conditions, and to notify necessity for re-adjustment of steady state design specification values. This system was also utilized to generate a sensitivity survey program in order to evaluate appropriateness of Monju design. The appropriateness of Monju design was evaluated in two ways. The first one is to follow specification selecting sequence as the as-built Monju has actually been designed. The second one is hypothetical deviations of major specifications of Monju and observation of the influences on other specifications. As a result, Monju design was confirmed to be adequate from the view point of need to meet design limitations at the design stage of Monju. This system is expected to be systematically re-arranged, because the system has now considerably complicated configuration after additions of various programs for many objects. This arrangement will facilitate future contribution of this system to technical studies in order for development of FBRs.

Observation of combustion-derived iron oxides in East Asia; Potential enhancement of aerosol light absorption

Tsuchiya, Nozomu*; Yamada, Rena*; Hata, Mitsuhiko*; Furuuchi, Masami*; Matsuki, Atsushi*; Ikemori, Fumikazu*; Kawasaki, Kazuo*; Iwamoto, Yoko*; Kaneyasu, Naoki*; Watanabe, Takahiro; et al.

no journal, , 

This study aimed to elucidate the seasonal (temporal) variation of iron oxides and their source based on the annual observation using environmental magnetic measurement at a downwind remote site in Noto. As a result, iron oxides (magnetization) showed a similar variation to black carbon (BC), but the BC-magnetization ratio increased/decreased depending on the combustion source: coal (continental), oil (domestic), biomass. This ratio can therefore be regarded as an environmental proxy to identify the combustion source.

Applications of the phase conjugate mirror to Thomson scattering diagnostics

Hatae, Takaki; Yamada, Ichihiro*; Yoshida, Hidetsugu*; Narihara, Kazumichi*; Fujita, Hisanori*; Nakatsuka, Masahiro*; Funaba, Hisamichi*; Minami, Takashi*; Kajita, Shin*; Tojo, Hiroshi; et al.

no journal, , 

no abstracts in English

Source apportionment of carbonaceous matter in PM at NOTO peninsula using C analysis

Yamada, Rena*; Ikemori, Fumikazu*; Nakamura, Toshio*; Minami, Masayo*; Watanabe, Takahiro; Kinouchi, Kento*; Matsuki, Atsushi*

no journal, , 

Aerosols and clouds seeded by them both affect the heat budget of the Earth, but their RF (radiative forcing) still involves large uncertainty (IPCC 2013). One of the least understood properties of aerosols is the source and contribution of the organics. Our recent observation revealed that submicron aerosol particles in Noto peninsula also have a relatively high concentration (approximately more than 50%) of carbonaceous matter throughout the year. It is difficult to presume its sources specifying its chemical species in many scenes because of its great variety. However, we can presume its source by using carbon isotope ratio. We conducted sampling in NOTOGRO (NOTO ground-based research observatory), lying at the edge of Noto peninsula, from 26th Jun to 23rd July, 2014. We corrected PM using high volume air sampler for every week. Flow rate was 700L/min, and quartz fiber filter was used for sampling. C was analyzed using AMS C system (High Voltage Engineering Europe, Model 4130-AMS) and C using IRMS (isotope ratio mass spectrometer) in Nagoya University. As a result, it was found that 4 samples collected from 26th Jun to 23rd July had approximately 70 percent modern carbon (pMC). This result shows that modern plant (and/or biomass burning) activities mainly contribute to the submicron organic particle concentration in Noto peninsula.