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Yang, X.*; Che, G.*; Wang, Y.*; Zhang, P.*; Tang, X.*; Lang, P.*; Gao, D.*; Wang, X.*; Wang, Y.*; Hattori, Takanori; et al.
Nano Letters, 25(3), p.1028 - 1035, 2025/01
Times Cited Count:0 Percentile:0.00(Chemistry, Multidisciplinary)Saturated sp-carbon nanothreads (CNTh) have garnered significant interest due to their predicted high Young's modulus and thermal conductivity. While the incorporation of heteroatoms into the central ring has been shown to influence the formation of CNTh and yield chemically homogeneous products, the impact of pendant groups on the polymerization process remains underexplored. In this study, we investigate the pressure-induced polymerization of phenol, revealing two phase transitions occurring below 0.5 and 4 GPa. Above 20 GPa, phenol polymerizes into degree-4 CNThs featuring hydroxyl and carbonyl groups. Hydrogen transfer of hydroxyl groups was found to hinder the formation of degree-6 nanothreads. Our findings highlight the crucial role of the hydroxyl group in halting further intracolumn polymerization and offer valuable insights for future mechanism research and nanomaterial synthesis.
Che, G.*; Fei, Y.*; Tang, X.*; Zhao, Z.*; Hattori, Takanori; Abe, Jun*; Wang, X.*; Ju, J.*; Dong, X.*; Wang, Y.*; et al.
Physical Chemistry Chemical Physics, 27(2), p.1112 - 1118, 2025/01
Times Cited Count:1 Percentile:0.00(Chemistry, Physical)Pressure-induced polymerization (PIP) of aromatic molecules has emerged as an effective method for synthesizing various carbon-based materials. In this work, PIP of 1,4-difluorobenzene (1,4-DFB) was investigated. high-pressure investigations of 1,4-DFB reveal a phase transition at approximately 12.0 GPa and an irreversible chemical reaction at 18.7 GPa. Structural analysis of the product and the kinetics of the reaction uncovered the formation of pseudohexagonal stacked fluoro-diamond nanothreads with linear growth. Compared to the crystal structures of benzene under high pressure, 1,4-DFB exhibits higher compression along the [001] axis. The anisotropic compression is attributed to the stronger H
interaction along the [01
] axis and the potential compression-inhibiting H
F interactions along the [100] and [010] axes, and it facilitates a possible reaction pathway along the [01
] axis. This work emphasizes the crucial role of functionalization in modulating molecular stacking and influencing the reaction pathway.
Horita, Takuma; Asai, Shiho*; Konda, Miki; Matsueda, Makoto; Hanzawa, Yukiko; Kitatsuji, Yoshihiro
Bunseki Kagaku, 69(10/11), p.619 - 626, 2020/10
Times Cited Count:0 Percentile:0.00(Chemistry, Analytical)We have developed a Sr adsorption fiber for rapid analysis of 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
. 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
Sr was finally determined by a GM counter. The total analysis time including the Sr adsorption and measurement was about 1 hour.
Seko, Noriaki*; Hoshina, Hiroyuki*; Kasai, Noboru*; Shibata, Takuya; Saiki, Seiichi*; Ueki, Yuji*
Radiation Physics and Chemistry, 143, p.33 - 37, 2018/02
Times Cited Count:19 Percentile:85.56(Chemistry, Physical)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
Times Cited Count:36 Percentile:69.85(Chemistry, Physical)no abstracts in English
Chen, J.; Asano, Masaharu; Yamaki, Tetsuya; Yoshida, Masaru
Journal of Applied Polymer Science, 100(6), p.4565 - 4574, 2006/06
Times Cited Count:44 Percentile:75.02(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% HO
at 50
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.
Narumi, Kazumasa; Sakai, Seiji; Naramoto, Hiroshi*; Takanashi, Koki
JAEA-Review 2005-001, TIARA Annual Report 2004, p.238 - 240, 2006/01
no abstracts in English
Narumi, Kazumasa; Sakai, Seiji; Naramoto, Hiroshi*; Takanashi, Koki
Fullerenes, Nanotubes, and Carbon Nanostructures, 14(2-3), p.429 - 434, 2006/00
no abstracts in English
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 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.
Asai, Shiho; Watanabe, Kazuo; Sugo, Takanobu*; Saito, Kyoichi*
Journal of Chromatography A, 1094(1-2), p.158 - 164, 2005/11
Times Cited Count:23 Percentile:54.66(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 CNH group allows the polymer brush to extend itself due to electrostatic repulsion originating from the amino part of the C
NH group.
Chen, J.; Asano, Masaharu; Tsubokawa, Norio*; Maekawa, Yasunari; Yamaki, Tetsuya; Yoshida, Masaru
Journal of Polymer Science, Part B; Polymer Physics, 43(20), p.2843 - 2851, 2005/10
Times Cited Count:0 Percentile:0.00(Polymer Science)Impedance spectra analysis of a thermo-responsive poly(acryloyl--proline methyl ester) (poly(A-ProOMe)) hydrogel membranes in an aqueous solution of LiCl was carried out using a simple equivalent model. The hydrogel membrane was synthesized by
-radiation-induced polymerization and crosslinking of A-ProOMe monomer aqueous solution in a glass-cast. By means of the impedance spectra analysis, a novel method for the calculation of the ionic conductivity of the hydrogel membranes in LiCl solution was proposed. The calculated ionic conductivity was in agreement well with the determined value. In addition, effects of temperature and LiCl concentration on the impedance spectra and ionic conductivity of the gel membrane were analysized. Results indicated that the impedance spectra analysis is a very useful tool for evaluating the electric properties of gel membranes in an electrolyte solution. The poly(A-ProOMe) gel membrane in 1.0 M LiCl solution showed a high ionic conductivity of about 0.2 S/cm at 14
C. The temperature-dependence of the ionic conductivity was a complex nonlinear form due to the volume phase transition of the thermo-responsive poly(A-ProOMe) gel membrane, and the volume phase transition temperature appeared to be decreased with the increase in the LiCl concentration.
Enomoto, Kazuyuki*; Narita, Tadashi*; Maekawa, Yasunari; Yoshida, Masaru; Hamana, Hiroshi*
Journal of Fluorine Chemistry, 125(7), p.1153 - 1158, 2004/07
Times Cited Count:3 Percentile:10.69(Chemistry, Inorganic & Nuclear)Radical polyaddition of bis(-trifluoromethyl-
,
-difluorovinyl) terephthalate (BFP) with 1,4-dioxane (DOX) afforded higher molecular weight polymers under
-rays compared to those yielded by benzoyl peroxide initiation. More detailed study on the radiation-induced polyaddition of BFP with DOX and optimization of the reaction conditions were carried out. It was necessary to irradiate with doses of 2000, 1500, and 750 kGy, to obtain quantitative conversion of BFP at the feed molar ratio DOX/BFP of 8.0, 16, and 32, respectively. Step-growth polymerization mechanism was suggested by the measurements of molecular weights of the polymers obtained with several irradiation doses. It was concluded that the molecular weight of the polymer could be controlled by the feed molar ratio of DOX/BFP and irradiation doses. The reaction between polymers might take place after the quantitative conversion of BFP. Radiation-induced radical polyaddition mechanism of BFP with DOX was proposed.
Lavrentiev, V.; Abe, Hiroaki; Yamamoto, Shunya; Naramoto, Hiroshi; Narumi, Kazumasa
Physica B; Condensed Matter, 323(1-4), p.303 - 305, 2002/10
Times Cited Count:15 Percentile:58.70(Physics, Condensed Matter)no abstracts in English
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
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 .
; Isoda, S.*; Kurata, Hiroki; ; ; Kobayashi, Takashi*
Polymer, 39(3), p.591 - 597, 1998/00
Times Cited Count:5 Percentile:26.52(Polymer Science)no abstracts in English
JAERI-Review 95-015, 67 Pages, 1995/10
no abstracts in English
; ; ; Hatada, Motoyoshi
Journal of Applied Polymer Science, 55, p.1643 - 1649, 1995/00
Times Cited Count:0 Percentile:0.00(Polymer Science)no abstracts in English
JAERI-M 94-017, 58 Pages, 1994/03
no abstracts in English
Zhaoxin, L.*; Fujimura, Takashi
Radiation Physics and Chemistry, 42(4-6), p.923 - 926, 1993/10
no abstracts in English
L.Z.Xin*; M.Carenza*; Kaetsu, Isao*; Kumakura, Minoru*; Yoshida, Masaru; Fujimura, Takashi
Radiation Physics and Chemistry, 40(6), p.579 - 584, 1992/00
no abstracts in English