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1.
Miwa T 《Die Naturwissenschaften》2007,94(7):551-560
I studied the conditions controlling the timing of breeding migration of the Japanese mountain stream frog Rana sakuraii, an explosive breeder, over 9 years (1992, 1993 and 1999–2005). I analysed two factors: the daily cumulative temperature
(DCT) during hibernation and the triggering temperature on the day of migration onset. Frogs hibernated in shallow running
water in streams in December. A total of 53,155 breeding migrating adults were captured by traps. Every year, breeding migration
was induced by a rise in daily maximum water temperature to about 5°C. However, its date was limited to 1 February at the
earliest, and the onset needed a DCT (from 20 January, using 3°C as the threshold for daily effective temperature) of at least
about 15°C. Earlier (e.g. in mid- or late January), even if the maximum temperature rose to 5–8°C, migration did not begin.
Moreover, even in early February, if the maximum temperature rose to 5°C, if it had been too cold in January and the DCT was
low, migration would not begin until mid- or late February. Thus, the earliest date of readiness for migration varied from
1 February to mid-February, depending on the winter DCT. Logistic regression analyses showed that both factors, the DCT and
the daily temperature, were significant. I propose that in temperate-zone amphibian explosive breeders, both the passing of
an essential number of days and an essential DCT during hibernation are prerequisites for the onset of breeding migration
before the daily temperature rises to the threshold. 相似文献
2.
Jun-ichi Kadokawa Takeshi Kato Miwa Setoyama Kazuya Yamamoto 《Journal of Polymers and the Environment》2013,21(2):512-519
This paper reports the preparation of galactomannan/ionic liquid composite materials from the corresponding ion gels. Three kinds of galactomannans, that is, fenugreek gum (FG), guar gum (GG), and locust bean gum (LBG) and an ionic liquid of 1-butyl-3-methylimidazolium chloride (BMIMCl) were used. When the galactomannan/BMIMCl gels were immersed in ethanol, followed by dryness under reduced pressure, the galactomannan/BMIMCl composite materials were obtained. The crystalline structures of galactomannans in the materials were evaluated by the powder X-ray diffraction measurement. The mechanical property of the FG/BMIMCl composite material under compressive mode was superior compared with the GG and LBG/BMIMCl composite materials. Then, FG films compatibilized with polymeric ionic liquids (PILs) were also prepared by in situ radical polymerization of polymerizable ionic liquids, 1-(3-acryloyloxypropyl)-3-vinylimidazolium bromide and 1-methyl-3-vinylbenzylimidazolium chloride by AIBN in mixtures of FG with BMIMCl. The mechanical properties of the resulting films were affected by the FG/PIL ratios as well as the unit ratios in PILs. 相似文献
3.
Katsuhiro Okamoto Norimichi Watanabe Yasuaki Hagimoto Koji Miwa Hideo Ohtani 《Journal of Loss Prevention in the Process Industries》2010,23(1):89-97
Evaporation rate of multi-component liquid such as motor gasoline is expected to change greatly with progress of evaporation because its composition changes. Therefore it is difficult to predict accurately amount of generated combustible vapor in the case that a multi-component liquid is spilt on a floor. Then, we assumed an evaporation model that composition of the vapor obeys the Raoult's law which considers the activity coefficient. Using the model, we calculated the vapor composition, the vapor pressure and the evaporation rate of the liquid. Then, comparison was done between the calculated values and the measured values obtained in this study. “Weight loss fraction” was used as a parameter signifying the progress of evaporation. The variations of the evaporation property were accurately predicted by the model. We derived a prediction model of the amount of generated combustible vapor from the relation between weight loss fraction and evaporation rate. It was found that the amount of generated vapor was expressed as a logarithmic function of time in case of a five-component liquid. Furthermore, we showed that the predicted flash point of a liquid using the composition obtained from the model was in good agreement with an experimental result. 相似文献
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6.
Yoshihisa Kohno Hideyuki Matsumura Makoto Miwa Tetsushi Yonekura Keiji Aihara Chanin Umponstira Vo Thanh Le Nguyen Thuy Ngoc Phanm Hung Viet Ma Wei 《Environmental monitoring and assessment》2013,185(3):2755-2765
We developed small and mobile open top chambers (mini-OTC) measuring 0.6 m (W)?×?0.6 m (D)?×?1.2 m (H) with an air duct of 0.6 m (W)?×?0.23 m (D)?×?1.2 m (H). The air duct can be filled with activated charcoal to blow charcoal filtered air (CF) into the chamber, as opposed to non-filtered ambient air (NF). Ozone sensitive radish Raphanus sativus cv. Red Chime and rosette pakchoi Brassica campestris var. rosularis cv. ATU171 were exposed to NF and CF in mini-OTCs at different locations in East Asia. A total of 29 exposure experiments were conducted at nine locations, Shanghai, China, Ha Noi, Vietnam, Lampang, Phitsanulok and Pathumtani, Thailand, and Hiratsuka, Kisai, Abiko and Akagi, Japan. Although no significant relationships between the mean concentrations of ambient O3 during the experimental period and the growth responses were observed for either species, multiple linear regression analysis suggested a good relationship between the biomass responses in each species and the O3 concentration, temperature, and relative humidity. The cumulative daily mean O3 (ppb/day) could be indirectly predicted by NF/CF based on the dry weight ratio of biomass, mean air temperature, and relative air humidity. 相似文献
7.
Miwa Setoyama Kazuya Yamamoto Jun-ichi Kadokawa 《Journal of Polymers and the Environment》2014,22(3):298-303
This paper reports the preparation of cellulose/xanthan gum composite films and hydrogels through gelation with an ionic liquid. Mixtures of cellulose and xanthan gum in desired weight ratios with an ionic liquid, 1-butyl-3-methylimidazolium chloride (BMIMCl), were thinly placed on a Petri dish and heated at 100 °C for 9 h to obtain the solutions. Then, the solutions were left standing at room temperature for 1 day for the progress of gelation. The resulting ion gels were subjected to Soxhlet extraction with ethanol to remove BMIMCl, followed by drying under ambient conditions to obtain the composite films. The crystalline structures of the polysaccharides and the mechanical properties were evaluated by powder X-ray diffraction measurement and tensile testing of the films, respectively. The ion gels in various cellulose/xanthan gum weight ratios, which were prepared in a test tube by the same procedure, were immersed in water for the exchange of disperse media to obtain the cellulose/xanthan gum composite hydrogels. Water contents of all the materials were higher than 90 %. The mechanical properties of the hydrogels were evaluated by compressive testing. 相似文献
8.
Oliveira RT Salazar-Banda GR Santos MC Calegaro ML Miwa DW Machado SA Avaca LA 《Chemosphere》2007,66(11):2152-2158
This work presents an electrochemical investigation of the benzene oxidation process in aqueous solution on boron-doped diamond (BDD) electrodes. Additionally, in order to determine the main products generated during the oxidation process, electrolysis and high performance liquid chromatography experiments were carried out. The complete degradation of this compound was performed aiming to a further application in waste water treatment. The cyclic voltammetry studies indicate that benzene is irreversibly oxidized in acid medium (H2SO4 0.5 M) on the BDD electrode surface at 2.0 V versus Ag/AgCl in a diffusion controlled process. During the cycling, other products are generated, and a pair of peaks was observed that can be associated with the oxi-reduction of anyone of the following species: hydroquinone, benzoquinone, resorcinol or catechol. The electrolysis experiments were carried out at 2.4 and 2.5 V on the BDD electrode surface in a solution containing 1 × 10−2 M of benzene (below the saturation concentration in aqueous solution), for 3 and 5 h, respectively. The main products measured were: hydroquinone, resorcinol, p-benzoquinone, catechol and phenol. The complete electrochemical benzene degradation was performed in the electrolysis experiments using a rotating BDD disc electrode (2.5 V for 5 h) and the main products detected were all measured at concentrations lower than 10−5 M in this condition. The boron-doped diamond electrode had proved to be a valuable tool for the electrochemical degradation of the benzene, a very stable chemical compound. 相似文献
9.
Hongyu Huang Noriyuki Kobayashi Miwa Sakata Yuko Suzuki Fujio Watanabe Masanobu Hasatani Kiyoshi Matsuyama Shigenori Yoshida Yoshihito Mitsuhara 《Journal of Material Cycles and Waste Management》2007,9(2):182-187
Polychlorinated biphenyl (PCB) residues from the sodium dispersion (SD) process were employed as the raw materials for the
production of activated carbon using KOH activation. The pore properties, such as the specific surface area and pore size
distribution, were characterized using the Barrett–Joyner–Halenda method and the Horvath–Kawazoe method based on the N2 adsorption isotherm at 77 K. The activated carbon produced showed similar adsorption capacities and specific surface areas
to the commercially available product. The effects of the activation conditions on the porosity of the activated carbon produced
were studied. The most significant factor affecting the specific surface proved to be the activation temperature. The activated
carbon produced from PCB residues from the high-temperature (423–443 K) SD process had a binary pore size distribution well
developed in the 4 nm region and in the micropore region. The pore structure of the carbon produced from PCB residues from
the low-temperature (333–393 K) SD process had a wide range of micropores and mesopores. 相似文献
10.
Geoffroy R. P. Malpass Douglas W. Miwa Ricardo L. Santos Eny M. Vieira Artur J. Motheo 《Environmental Chemistry Letters》2012,10(2):177-182
This report shows an unexpected toxicity decrease during atrazine photoelectrodegradation in the presence of NaCl. Atrazine
is a pesticide classified as endocrine disruptor occurring in industrial effluents and agricultural wastewaters. We therefore
studied the effects of the degradation method, electrochemical and electrochemical photo-assisted, and of the supporting electrolyte,
NaCl and Na2SO4, on the residual toxicity of treated atrazine solutions. We also studied the toxicity of treated atrazine solutions using
Artemia nauplii. Results show that at initial concentration of 20 mg L−1, atrazine was completely removed in up to 30 min using 10 mA cm−2 electrolysis in NaCl medium, regardless of the electrochemical method used. The total organic carbon removal by the photo-assisted
method was 82% with NaCl and 95% with Na2SO4. The solution toxicity increased during sole electrochemical treatment in NaCl, as expected. However, the toxicity unexpectedly
decreased using the photo-assisted method. This finding is a major discovery because electrochemical treatment with NaCl usually
leads to the formation of toxic chlorine-containing organic degradation by-products. 相似文献