Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 65

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 ...

Save select records

Journal Articles

Radiation response of silicon carbide metal-oxide-semiconductor transistors in high dose region

Oshima, Takeshi; Yokoseki, Takashi; Murata, Koichi; Matsuda, Takuma; Mitomo, Satoshi; Abe, Hiroshi; Makino, Takahiro; Onoda, Shinobu; Hijikata, Yasuto*; Tanaka, Yuki*; et al.

Japanese Journal of Applied Physics, 55(1S), p.01AD01_1 - 01AD01_4, 2016/01

 Times Cited Count:12 Percentile:55.22(Physics, Applied)

Journal Articles

Emulsion grafting of vinyl acetate onto preirradiated poly(3-hydroxybutyrate) film

Wada, Yuki*; Tamada, Masao; Seko, Noriaki; Mitomo, Hiroshi*

Journal of Applied Polymer Science, 107(4), p.2289 - 2294, 2008/02

 Times Cited Count:14 Percentile:42.21(Polymer Science)

Vinyl acetate (VAc) was grafted onto poly(3-hydroxybutyrate) (PHB) film by preirradiation method. Grafting reactions were carried out in a VAc/water/surfactant emulsion, VAc/water, and VAc/methanol systems. For emulsion grafting, Nonion L-4 was ascertained to be the optimum surfactant with regard to the stability of a single emulsion layer. The emulsion with a 10:1 (w/w) ratio of VAc and surfactant yielded the highest degree of grafting (Xg) 23%. The grafting efficiency in the emulsion and the water and methanol solvent were evaluated. The results indicated that the grafting efficiency of the emulsion is 100 times that of VAc/methanol when the same 2 wt% VAc was used in the grafting reaction.

Journal Articles

Biodegradability of poly(3-hydroxybutyrate) film grafted with vinyl acetate; Effect of grafting and saponification

Wada, Yuki; Seko, Noriaki; Nagasawa, Naotsugu; Tamada, Masao; Kasuya, Kenichi*; Mitomo, Hiroshi*

Radiation Physics and Chemistry, 76(6), p.1075 - 1083, 2007/06

 Times Cited Count:20 Percentile:78.38(Chemistry, Physical)

Radiation-induced graft polymerization of vinyl acetate (VAc) onto poly(3-hydroxybutyrate) (PHB) film was carried out. At a degree of grafting higher than 5%, the grafted films (PHB-g-VAc) completely lost the enzymatic degradability that is characteristic of PHB due to the grafted VAc covering the surface of the PHB film. However, the biodegradability of the PHB-g-VAc films was recovered when the films were saponified in alkali solution under optimum conditions. Graft chains of the PHB-g-VAc film reacted selectively to become biodegradable polyvinyl alcohol (PVA). The biodegradability of the saponified PHB-g-VAc film increased rapidly with time.

Journal Articles

Properties of crosslinked polylactides (PLLA & PDLA) by radiation and its biodegradability

Quynh, T. M.*; Mitomo, Hiroshi*; Nagasawa, Naotsugu; Wada, Yuki; Yoshii, Fumio; Tamada, Masao

European Polymer Journal, 43(5), p.1779 - 1785, 2007/05

 Times Cited Count:112 Percentile:95.01(Polymer Science)

Crosslinked materials derived from poly(lactide) (PLA) have been produced by radiation modification in the presence of a suitable crosslinker (triallyl isocyanurate: TAIC). The crosslinking structure introduced in PLA films has not only much improved the heat stability but also their mechanical properties. The properties of crosslinked samples are governed by crosslinking density and these improvement seemed to increase with radiation dose. This implied that the three dimensional networks have been introduced in material by radiation and the crosslinking density depended on the structure and length of PLA chains. Biodegradability of PLA was also determined by an enzymatic degradation test and burying in compost at 55 $$^{circ}$$C. Differing with PLLA, PDLA was insignificantly degraded by ${it proteinase K}$. The degradation rate of PLA in compost was postponed with the introduction of crosslinks.

Journal Articles

Problems with the current deinococcal hypothesis; An Alternative theory

Sghaier, H.; Narumi, Issei; Sato, Katsuya; Oba, Hirofumi; Mitomo, Hiroshi*

Theory in Biosciences, 126(1), p.43 - 45, 2007/03

 Times Cited Count:15 Percentile:85.71(Biology)

no abstracts in English

Journal Articles

Off-on biodegradability of poly(3-hydroxybutyrate) film modified by graft polymerization

Wada, Yuki; Mitomo, Hiroshi*; Seko, Noriaki; Tamada, Masao

JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 51, 2007/02

no abstracts in English

Journal Articles

Metal adsorption of chitin / chitosan derivatives hydrogels crosslinked with irradiation

Nagasawa, Naotsugu; Wasikiewicz, J. M.*; Seko, Noriaki; Yagi, Toshiaki; Zhao, L.*; Mitomo, Hiroshi*; Yoshii, Fumio; Tamada, Masao

JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 52, 2007/02

Radiation crosslinking of chitin / chitosan derivatives such as carboxymethylchitin (CMCt) and carboxymethylchitosan (CMCts) has been investigated. CMCt and CMCts of 40% concentration were irradiated by electron beams. The maximum gel fraction of those CMCht and CMChts reached 72% (75kGy) and 50% (100kGy) respectively. These gels absorpted water of 8.3g for CMCt and 21.2g for CMCts per 1 g of the dried gel. The absorption ability of various metal ions with these gels has been investigated. The highest adsorption of scandium and gold has been obtained for CMCt and CMCts gels, respectively.

Journal Articles

Modification of poly(lactic acid) by radiation-induced crosslinking

Nagasawa, Naotsugu; Kaneda, Ayako*; Matsuzaki, Tomoaki*; Kanazawa, Shinichi*; Yagi, Toshiaki; Tran, M. Q.*; Mitomo, Hiroshi*; Yoshii, Fumio; Tamada, Masao; Quynh, T. M.*

JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 53, 2007/02

Poly(L-lactic acid), PLA was irradiated using electron beams (EB) in the presence of polyfunctional monomers (PFM) as crosslinking agent. Among the PFMs, triallyl isocyanurate (TAIC) at 3% concentration was found to be the most effective for crosslinking of PLA by irradiation technique. The crosslinked PLA obtained has heat resistance higher than 200$$^{circ}$$C. From this fact, the crosslinked PLA is applied on heat-shrinkable tube, cup and plate. The shrinkable tube has several advantages such as high heat resistance and transparency. It is therefore proven that crosslinking technology is beneficial to expanding the application of PLA.

Journal Articles

Control of biodegradability of poly(3-hydroxybutyric acid) film with grafting acrylic acid and thermal remolding

Wada, Yuki; Mitomo, Hiroshi*; Kasuya, Kenichi*; Nagasawa, Naotsugu; Seko, Noriaki; Katakai, Akio; Tamada, Masao

Journal of Applied Polymer Science, 101(6), p.3856 - 3861, 2006/09

 Times Cited Count:21 Percentile:53.7(Polymer Science)

Radiation-induced graft polymerization of acrylic acid (AAc) on the surface of poly(3-hydroxybutyric acid) (PHB) film was carried out by applying pre-irradiation techniques. The PHB films grafted with AAc (PHB-g-AAc) possessed a degree of grafting higher than 5% have completely lost the enzymatic degradability. The enzymatic degradability of the grafted film was recovered by remolding. And the highest enzymatic degradation rate was observed to grafted films with AAc 10% of degree. Difference of enzymatic degradability of PHB-g-AAc film was caused by decrement of amount of enzyme contact and decrement of crystallinity of PHB by remolding.

Journal Articles

Genomic confession of ${it Deinococcus radiodurans}$; It started out as a radiation resistant organism

Sghaier, H.; Mitomo, Hiroshi*; Narumi, Issei

Viva Origino, 33(4), p.243 - 257, 2005/12

Previously, analyses of ionizing-radiation-sensitive mutants of ${it Deinococcus radiodurans}$ and investigation into the genomic expression profile of the wild-type organism indicated a positive correlation between radiation resistance and desiccation tolerance phenotypes. Mainly because a terrestrial selective force for acquiring resistance to ionizing radiation was unfound, it has been assumed that the radiation resistance of ${it D. radiodurans}$ is an incidental phenotype due to its anhydrobiosis defense abilities. Here, following the stratification of the ${it D. radiodurans}$ genome, we discuss these issues from evolutionary, genomic, and experimental perspectives. Through the data collected we propose a reconciliatory model wherein radiation resistance is a unique molecular reflection of the early Earth resilience and desiccation tolerance is a mark of cells that colonized land during the Archaean epoch.

Journal Articles

Application of poly(lactic acid) modified by radiation crosslinking

Nagasawa, Naotsugu; Kaneda, Ayako*; Kanazawa, Shinichi*; Yagi, Toshiaki; Mitomo, Hiroshi*; Yoshii, Fumio; Tamada, Masao

Nuclear Instruments and Methods in Physics Research B, 236(1-4), p.611 - 616, 2005/07

 Times Cited Count:76 Percentile:97.9(Instruments & Instrumentation)

no abstracts in English

Journal Articles

Adsorption of metal ions by carboxymethylchitin and carboxymethylchitosan hydrogels

Wasikiewicz, J. M.; Nagasawa, Naotsugu; Tamada, Masao; Mitomo, Hiroshi*; Yoshii, Fumio

Nuclear Instruments and Methods in Physics Research B, 236(1-4), p.617 - 623, 2005/07

 Times Cited Count:53 Percentile:94.95(Instruments & Instrumentation)

The absorption ability of various metal ions into EB - radiation crosslinked carboxymethylchitin and carboxymethylchitosan has been investigated. The highest adsorption of Scandium and Gold has been obtained for carboxymethylchitin (CMCht) and carboxymethylchitosan (CMChts), respectively. Kinetic studies showed that adsorption of most of the metal ions occur in a relatively short period of time (2 hours). Detail investigation of adsorption of gold ions has been carried out for both hydrogels. The maximum uptake of Au cations, based on Langmuir equation was determined to be 37.59 mg/g for CMChts and 11.86 mg/g for CMCht. Both hydrogels indicate favorable adsorption of gold cations.

Journal Articles

Improvement of heat stability of poly($$_{L}$$-lactic acid) by radiation-induced crosslinking

Mitomo, Hiroshi*; Kaneda, Ayako*; Tran, M. Q.*; Nagasawa, Naotsugu; Yoshii, Fumio

Polymer, 46(13), p.4695 - 4703, 2005/06

 Times Cited Count:113 Percentile:94.35(Polymer Science)

no abstracts in English

Journal Articles

Preparation of crosslinked carboxymethylated chitin derivatives by irradiation and their sorption behavior for copper(II) ions

Zhao, L.; Mitomo, Hiroshi*; Yoshii, Fumio; Kume, Tamikazu

Journal of Applied Polymer Science, 91(1), p.556 - 562, 2004/01

no abstracts in English

Journal Articles

Preparation of crosslinked carboxymethylated chitin derivatives by irradiation and their sorption behavior for Copper(II) ions

Zhao, L.; Mitomo, Hiroshi*; Yoshii, Fumio; Kume, Tamikazu

Journal of Applied Polymer Science, 91(1), p.556 - 562, 2004/01

 Times Cited Count:20 Percentile:54.09(Polymer Science)

no abstracts in English

Journal Articles

Synthesis of antibacterial PVA/CM-chitosan blend hydrogels with electron beam irradiation

Zhao, L.; Mitomo, Hiroshi*; Zhai, M.*; Yoshii, Fumio; Nagasawa, Naotsugu; Kume, Tamikazu

Carbohydrate Polymers, 53(4), p.439 - 446, 2003/09

 Times Cited Count:197 Percentile:99.05(Chemistry, Applied)

no abstracts in English

Journal Articles

Radiation synthesis and characteristic of the hydrogels based on carboxymethylated chitin derivatives

Zhao, L.; Mitomo, Hiroshi*; Nagasawa, Naotsugu; Yoshii, Fumio; Kume, Tamikazu

Carbohydrate Polymers, 51(2), p.169 - 175, 2003/01

 Times Cited Count:111 Percentile:96.33(Chemistry, Applied)

no abstracts in English

Journal Articles

Radiation crosslinking of poly(butylene succinate) in the presence of low concentration of trimethallyl isocyanurate and its properties

Suhartini, M.; Mitomo, Hiroshi*; Nagasawa, Naotsugu; Yoshii, Fumio; Kume, Tamikazu

Journal of Applied Polymer Science, 88(9), p.2238 - 2246, 2003/00

 Times Cited Count:46 Percentile:79.9(Polymer Science)

no abstracts in English

Journal Articles

Hydrogel of radiation-induced cross-linked hydroxypropylcellulose

Wach, R. A.*; Mitomo, Hiroshi*; Yoshii, Fumio; Kume, Tamikazu

Macromolecular Materials and Engineering, 287(4), p.285 - 295, 2002/04

 Times Cited Count:58 Percentile:85.14(Materials Science, Multidisciplinary)

no abstracts in English

Journal Articles

Radiation crosslinking of poly(butylene succinate) in the presence of inorganic material and its biodegradability

Suhartini, M.; Mitomo, Hiroshi*; Yoshii, Fumio; Nagasawa, Naotsugu; Kume, Tamikazu

Journal of Polymers and the Environment, 9(4), p.163 - 171, 2001/10

 Times Cited Count:24 Percentile:65.02(Engineering, Environmental)

no abstracts in English

65 (Records 1-20 displayed on this page)