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Nakano K.,Fukuoka Industrial Technology Center
Chemistry Letters | Year: 2016

The influence of ultrasonication was investigated on the synthesis of nickel particles from aqueous solution including nickel hydrazine complex. Nickel nanoparticles were formed by heating up precursor solution having been prepared under ultrasonication in advance. The mean size of nickel nanoparticles decreased with increasing time of ultrasonication, and it reached 43nm with ultrasonication for 60min. © 2016 The Chemical Society of Japan. Source

Nishida H.,Kyushu Institute of Technology | Andou Y.,Kyushu Institute of Technology | Watanabe K.,Kyushu Institute of Technology | Arazoe Y.,Kyushu Institute of Technology | And 2 more authors.
Macromolecules | Year: 2011

A biomass-based and racemization-free polymer, poly(tetramethyl glycolide) (PTMG) possessing superior depolymerizability for the reproduction was developed. Renewable resources, D-/L-lactic acids and pyruvic acid derived from biomasses were employed as starting materials for the synthesis of HIBA (αhydroxyisobutyric acid). The biomass-based HIBA is prepared by methylation of the acids and then converted into the cyclic dimer. Two synthetic routes of HIBA from the renewable resources were performed. One was the direct methylation of D-/L-lactic acid derivatives after the abstraction of R-hydrogen on a chiral carbon and the other was the methylation of an R-keto group of a pyruvic acid derivative by the Grignard reaction. These results reveal PTMG as a superior recyclable material by the virtue of its controllable conversion into each monomer. Source

Tanaka M.,Kyushu University | Onomoto T.,Fukuoka Industrial Technology Center | Tsuchiyama T.,Kyushu University | Higashida K.,Kyushu University
ISIJ International | Year: 2012

The brittle-to-ductile transition (BDT) behaviour in nickel-free austenitic stainless steel with high nitrogen was investigated. Fall-weight impact tests revealed that Fe-25mass%Cr-1.1mass%N austenitic steel exhibits a sharp BDT behaviour in spite of an fcc alloy. The aspects of plastic deformation after the impact tests indicate that the BDT observed in this austenitic steel is induced by poor ductility at low temperatures as is the same as that in ferritic steels. In order to measure the activation energy for the BDT, the strain rate dependence of the BDT temperature was examined by using four-point bending tests. The weak dependence of the BDT temperature on the strain rate was observed. The Arrhenius plot of the BDT temperature against the strain rate elucidated that the activation energy for the BDT of Fe-25mass%Cr-1.1mass%N is much higher than that of low carbon ferritic steels. The origins of such distinct BDT behaviour and its large value of the activation energy in this high-nitrogen steel are discussed in terms of the reduction of dislocation mobility at low temperatures due to the interaction between glide dislocations and nitrogen solute atoms. © 2012 ISIJ. Source

Tsukatani T.,Fukuoka Industrial Technology Center
Nippon Shokuhin Kagaku Kogaku Kaishi | Year: 2015

To determine microbial populations and their viability, methods assessing colonies formed and turbidity are generally used. However, these methods require a long incubation time. Thus, a rapid colorimetric microbial viability assay based on the reduction of the tetrazolium salt WST-8 via 2-methyl-1,4-naphthoquinone as an electron mediator was developed. The applicability of the assay for susceptibility testing of various bacteria to antibiotics, screening of antimicrobial substances, determination of water-soluble vitamins, and differentiation of Gram-positive and - negative bacteria was investigated. Good agreement was observed between results with the WST-8 colorimetric method and those obtained using conventional methods. The present assay method was superior to the conventional methods with respect to the overall rapidity, accuracy and convenience. Copyright © 2015, Japanese Society for Food Science and Technology. Source

Sakai S.,Osaka University | Liu Y.,Kyushu University | Yamaguchi T.,Fukuoka Industrial Technology Center | Watanabe R.,Japan Vilene Co. | And 2 more authors.
Bioresource Technology | Year: 2010

Butyl-biodiesel production using electrospun polyacrylonitrile fibers with Pseudomonas cepacia lipase immobilized through physical adsorption was studied. About 80% conversion to butyl-biodiesel was achieved after 24 h by suspending the catalyst at 2.4 mg/mL in a mixture of rapeseed oil and n-butanol at a molar ratio of 1:3, containing water at 8000 ppm at 40 °C. A further 24 h of operation resulted in 94% conversion. The initial reaction rate detected for this process was 65-fold faster than those detected for Novozym 435 on a total catalyst mass basis. The immobilized lipase continued to work as a catalyst for 27 d, within a 15% reduction in conversion yield at the outlet of the reactor compared with the average value detected during the first 3 d of operation in a continuous butyl-biodiesel production system. © 2010 Elsevier Ltd. All rights reserved. Source

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