JOPSS - Search Results

Search Results: Records 1-20 displayed on this page of 34

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Journal Articles

Improvement of adsorption performances of Sr adsorption fiber and investigation for realizing simple $^{90}$ Sr analysis

Horita, Takuma; Asai, Shiho*; Konda, Miki; Matsueda, Makoto; Hanzawa, Yukiko; Kitatsuji, Yoshihiro

Bunseki Kagaku, 69(10/11), p.619 - 626, 2020/10

https://doi.org/10.2116/bunsekikagaku.69.619

Times Cited Count：0 Percentile：0(Chemistry, Analytical)

We have developed a Sr adsorption fiber for rapid analysis of $^{90}$ Sr. The prepared Sr adsorption fiber has a Sr-extraction layer that densely retains a Sr-selective extractant, an 18-crown-6 ether derivative, on the fiber surface. Hydrophobic group-containing polymer chains embedded onto the surface of the fiber allow to form a hydrophobic phase, incorporating Sr-selective extractants. This unique surface structure provides high adsorption capacity, leading to rapid and highly efficient adsorption of Sr $^{2+}$ . The adsorption capacity of the Sr adsorption fiber was 3 times higher than commercially available 18-crown-6 ether derivative-impregnated resin (Sr Resin). The equilibrium adsorption capacity of the Sr adsorption fiber was comparable to the Sr Resin. The retained $^{90}$ Sr was finally determined by a GM counter. The total analysis time including the Sr adsorption and measurement was about 1 hour.

Journal Articles

Development of a water purifier for radioactive cesium removal from contaminated natural water by radiation-induced graft polymerization

Seko, Noriaki*; Hoshina, Hiroyuki*; Kasai, Noboru*; Shibata, Takuya; Saiki, Seiichi*; Ueki, Yuji*

Radiation Physics and Chemistry, 143, p.33 - 37, 2018/02

https://doi.org/10.1016/j.radphyschem.2017.09.007

Times Cited Count：16 Percentile：84.77(Chemistry, Physical)

Journal Articles

Poly(ether ether ketone) (PEEK)-based graft-type polymer electrolyte membranes having high crystallinity for high conducting and mechanical properties under various humidified conditions

Hamada, Takashi; Hasegawa, Shin; Fukasawa, Hideyuki*; Sawada, Shinichi; Koshikawa, Hiroshi; Miyashita, Atsumi; Maekawa, Yasunari

Journal of Materials Chemistry A, 3(42), p.20983 - 20991, 2015/11

https://doi.org/10.1039/C5TA05567A

Times Cited Count：35 Percentile：70.48(Chemistry, Physical)

no abstracts in English

Journal Articles

Effect of crosslinkers on the preparation and properties of ETFE-based radiation-grafted polymer electrolyte membranes

Chen, J.; Asano, Masaharu; Yamaki, Tetsuya; Yoshida, Masaru

Journal of Applied Polymer Science, 100(6), p.4565 - 4574, 2006/06

https://doi.org/10.1002/app.22567

Times Cited Count：44 Percentile：75.66(Polymer Science)

This study concerns a comparative study of three crosslinkers, divinylbenzene (DVB), 1,2-bis(p,p-vinylphenyl)ethane (BVPE) and triallyl cyanurate (TAC) crosslinked poly(ethylene-co-tetrafluoroethylene) (ETFE)-based radiation-grafted membranes, which were prepared by radiation grafting of p-methylstyrene (MeSt) onto ETFE films and subsequent sulfonation. The effect of the different types and contents of the crosslinkers on the grafting and sulfonation, and the properties such as water uptake, proton conductivity and thermal/chemical stability of the resulting polymer electrolyte membranes was investigated in detail. Introducing crosslink structure into the radiation-grafted membranes leads to a decrease in proton conductivity due to the decrease in water uptake. The thermal stability of the crosslinked radiation-grafted membranes is also somewhat lower than that of the noncrosslinked one. However, the crosslinked radiation-grafted membranes show significantly higher chemical stability characterized in the 3% H $_{2}$ O $_{2}$ at 50 $^{circ}$ C. Among the three crosslinkers, the DVB shows a most pronounced efficiency on the crosslinking of the radiation-grafted membranes, while the TAC has no significant influence; the BVPE is a mild and effective crosslinker, showing the moderate influence between the DVB and TAC crosslinkers.

Journal Articles

Improvement of chemical stability of polymer electrolyte fuel cell membranes by grafting of new substituted styrene monomers into ETFE films

Chen, J.; Asano, Masaharu; Yamaki, Tetsuya; Yoshida, Masaru

Journal of Materials Science, 41(4), p.1289 - 1292, 2006/02

https://doi.org/10.1007/s10853-005-2573-8

Times Cited Count：22 Percentile：58.32(Materials Science, Multidisciplinary)

The MeSt/tBuSt/DVB-grafted polymer electrolyte membrane showed a high performance for the fuel cell applications. The tBuSt contributed the high chemical stability while the MeSt contributed the high conductivity to the resulted membrane. The DVB crosslinker in the membrane further improved the chemical stability. The new polymer electrolyte membrane with a degree of grafting of 36% showed proton conductivity as high as the Gore-Select membrane, and the durability time was about 3 times longer than that of the traditional styrene/DVB-grafted one. Therefore, the MeSt/tBuSt/DVB-grafted polymer electrolyte membrane was more possible to be used for the fuel cells.

Journal Articles

Preparation and characterization of chemically stable polymer electrolyte membranes by radiation-induced graft copolymerization of four monomers into ETFE films

Chen, J.; Asano, Masaharu; Yamaki, Tetsuya; Yoshida, Masaru

Journal of Membrane Science, 269(1-2), p.194 - 204, 2006/02

https://doi.org/10.1016/j.memsci.2005.06.035

Times Cited Count：140 Percentile：96.02(Engineering, Chemical)

To develop a highly chemically stable polymer electrolyte membrane for application in a direct methanol fuel cell (DMFC), four styrene derivative monomers, m,p-methylstyrene (MeSt), p-tert-butylstyrene (tBuSt), divinylbenzene (DVB) and bis(p,p-vinyl phenyl) ethane (BVPE) were graft copolymerized into poly(ethylene-co-tetrafluoroethylene) (ETFE) films followed by sulfonation and hydrolysis. The latter two monomers were used as crosslinkers. The graft copolymerization was carried out by the -ray preirradiation method. The influence of the preirradiation dose and the grafting kinetics were investigated in detail. Sulfonation of the grafted ETFE films was performed in a chlorosulfonic acid solution, by which the sulfonation ratio reached about 90%. The newly obtained membrane possesses significantly higher chemical stability than the traditional styrene/DVB-grafted membrane and six times lower methanol permeability compared to the Nafion 112 membrane. Therefore, this study reveals the possibility of the developed inexpensive four monomers-grafted membranes, which could provide an attractive alternative as a substitute for the expensive Nafion membranes for DMFC applications.

Journal Articles

Proton conduction properties of crosslinked PTFE electrolyte membranes with different graft-chain structures

Sawada, Shinichi; Yamaki, Tetsuya; Asano, Masaharu; Terai, Takayuki*; Yoshida, Masaru

Transactions of the Materials Research Society of Japan, 30(4), p.943 - 946, 2005/12

We synthesized crosslinked-polytetrafluoroethylene (PTFE) electrolyte membranes by a radiation grafting technique under different conditions, and then investigated their proton conduction properties at controlled temperatures and relative humidities (R.H.) by an AC impedance method. The density and length of graft chains were controlled by varying the pre-irradiation dose and grafting time, respectively. When the pre-irradiation dose was fixed at 15 kGy to make the graft chains an uniform density, the elongation of the graft chain increased the ion exchange capacity (IEC), there by enhancing their proton conductivity. The membrane with an IEC of 2.8 meq/g possessed the maximum conductivity reaching 0.20 S/cm at 80 $^{circ}$ C and R.H. 95%. At almost the same IEC, membranes with more and shorter graft chains showed higher conductivity than those with less and longer chains. This result was probably related to the different structures of hydrophilic domains as proton-conducting pathways.

Journal Articles

Preparation of an extractant-impregnated porous membrane for the high-speed separation of a metal ion

Asai, Shiho; Watanabe, Kazuo; Sugo, Takanobu*; Saito, Kyoichi*

Journal of Chromatography A, 1094(1-2), p.158 - 164, 2005/11

https://doi.org/10.1016/j.chroma.2005.07.095

Times Cited Count：23 Percentile：55.38(Biochemical Research Methods)

The analysis of radioactive species in radioactive wastes is essential to the safe and economical disposal of such wastes. Among radioactive species, alpha- and beta-emitting nuclides should be purified prior to various radiometric determinations. To overcome the disadvantages of the conventional separation techniques, we have proposed functional porous hollow-fiber membranes that achieve a high speed operation assisted by convective flow. Stable immobilization in aqueous media is ensured by the hydrophobic interaction between the hydrophobic moiety of the extractant and octadecyl part of octadecylamino group. In this study, HDEHP, which shows the selectivity for rare earth elements, such as yttrium, was immobilized onto the porous membrane. The amount of immobilized HDEHP increased with increasing molar conversion. This can be explained by the fact that an increase in the C $_{18}$ NH group allows the polymer brush to extend itself due to electrostatic repulsion originating from the amino part of the C $_{18}$ NH group.

Journal Articles

Thermo- and pH-sensitive gel membranes based on poly-(acryloyl--proline methyl ester)--poly(acrylic acid) for selective permeation of metal ions

Hasegawa, Shin; Ohashi, Hitoshi; Maekawa, Yasunari; Katakai, Ryoichi*; Yoshida, Masaru

Radiation Physics and Chemistry, 72(5), p.595 - 600, 2005/04

https://doi.org/10.1016/j.radphyschem.2004.03.016

Times Cited Count：16 Percentile：71.76(Chemistry, Physical)

Thermo- and pH-responsive gel membranes were synthesized by -ray grafting of pH-responsive poly (acrylic acid) (AAc) onto thermo-responsive polymer gel of acryloyl--proline methyl ester (A-ProOMe). The gel membranes of poly (A-ProOMe) with 15 mol% graft chains of AAc exhibited both thermo- and pH-responses. Under the condition (pH 6.0, 30 $^{circ}$ C) in which the thermo-sensitive unit shrinks and the pH-sensitive unit swells, the selective permeation of Li ion over Co and Ni ions can be achieved.

JAEA Reports

Transportation of significant metals recovered in real sea experiment of adsorbents

Takeda, Hayato*; Onuma, Kenji*; Tamada, Masao; Kasai, Noboru; Katakai, Akio; Hasegawa, Shin; Seko, Noriaki; Kawabata, Yukiya*; Sugo, Takanobu

JAERI-Tech 2001-062, 66 Pages, 2001/10

JAERI-Tech-2001-062.pdf:5.5MB

Real sea experiment for the recovery of significant metals such as uranium and vanadium has been carried out at the offing of Mutsu establishment to evaluate the adsorption performance of adsorbent synthesized by radiation-induced graft-polymerization. After elution of uranium and vanadium from the adsorbent, their metals were adsorbed onto the conventional chelate resin. This chelate resin in a plastic column was further put in a cylindrical stainless transport container. The container was transported to the facility for separation and purification by a truck for the exclusive loading. The maximum concentration is 60 Bq/g when the uranium is adsorbed on the chelate resin. Transportation of recovered metals can be treated as general substance since these amount and concentration are out of legal control. However, the recovered metals were transported in conformity to L type transportation as a voluntary regulation. The strength analysis of the container was equal to the safety level of IP-2 type which is higher transportation grade than L type .

Journal Articles