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21.
Effects of Nitrogen Supply on the Sensitivity to O3 of Growth and Photosynthesis of Japanese Beech (Fagus crenata) Seedlings 总被引:1,自引:0,他引:1
Masahiro Yamaguchi Makoto Watanabe Naoki Matsuo Junichi Naba Ryo Funada Motohiro Fukami Hideyuki Matsumura Yoshihisa Kohno Takeshi Izuta 《Water, Air, & Soil Pollution: Focus》2007,7(1-3):131-136
To obtain basic information for evaluating critical levels of O3 under different nitrogen loads for protecting Japanese beech forests, two-year-old seedlings of Fagus crenata Blume were grown in potted andisol supplied with N as NH4NO3 solution at 0, 20 or 50 kg ha−1 year−1 and exposed to charcoal-filtered air or O3 at 1.0, 1.5 and 2.0 times the ambient concentration from 16 April to 22 September 2004. The O3 induced significant reductions in the whole-plant dry mass, net photosynthetic rate at 380 μmol mol−1 CO2 (A
380), carboxylation efficiency (CE) and concentrations of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and total soluble protein (TSP) in the leaves.
The concentrations of Rubisco and TSP were negatively correlated with the concentration of leaf acidic amino acid, suggesting
that O3 enhanced the degradation of protein such as Rubisco. The N supply to the soil did not significantly change the whole-plant
dry mass and A
380, whereas it significantly increased the CE and concentrations of Rubisco and total amino acid. No significant interactive effects of O3 and N supply to the soil were detected on the growth, photosynthetic parameters and concentrations of protein and amino acid
in the leaves. In conclusion, N supply to the soil at ≤50 kg ha−1 year−1 does not significantly change the sensitivity to O3 of growth and net photosynthesis of Fagus crenata seedlings. 相似文献
22.
Yearling carp (Cyprinus carpio) were exposed to d-phenothrin (a 1:4 mixture of d-cis and d-trans isomers) in the absence and the presence of piperonyl butoxide under the flow-through test condition and the bioconcentration factors (BCF's) of the geometric isomers were separately evaluated. It was demonstrated that BCF values for the d-cis isomer were significantly higher by 1.1 to 2.2-fold than those for the d-trans isomer and the subsequent exposure in the presence of piperonyl butoxide resulted in elevated BCF values for the d-cis isomer, but no remarkable change in BCF's was observed for the d-trans isomer. The elevation observed here was presumably attributable to a reduced elimination caused by inhibited oxidative reactions characteristic to the d-cis isomer. The contribution of biotransformation to the elimination rate constant (K3/K2 was estimated to be 2.3–11. Thus, the result was well explained by a distinct oxidative metabolism of the d-cis isomer and a significance of metabolism in bioconcentration phenomenon was exemplified. 相似文献
23.
The oxidation of antimony(III) in soils was studied using X-ray absorption fine structure(XAFS)spectra.An andosol soil sample and artificial soil samples(SiO_2 blended with iron(III) hydroxide and manganese(IV) oxide) were used herein.After adding antimony(III) oxide to all soil samples,the oxidation process was observed by recording the XAFS spectra of Sb K-edge,Fe Kedge,and Mn K-edge.The results indicated that manganese(IV) oxide played an important role in the oxidation of Sb(III);however iron(III) hydroxide was not directly related to the reaction.During a 2-hr continuous Sb K-edge X-ray absorption near edge structure(XANES) measurement with an interval of 1 min of one of the artificial soil samples(SiO_2+ MnO_2+ Sb_2O_3),a pseudo-first-order reaction was determined with an average estimated rate of 0.52 ± 0.04 hr-1.Compared to the lower oxidation rate of andosol,it is suggested that because of the low concentration of Mn(IV) in natural soils,the oxidation process of Sb(III) might be relatively slow and require more time to convert Sb(III) to Sb(V). 相似文献
24.
Hiroaki Miura Akiko Matsuo Go Tabuchi 《Journal of Loss Prevention in the Process Industries》2013,26(2):329-337
The three-dimensional and two-dimensional axisymmetric fluid dynamics simulations were carried out to clarify the blast pressure mitigating effects of dike’s configuration in hemispherical explosion. The simulated peak overpressure on the ground under the hemispherical explosion was compared with the empirical formula by Kingery, and the simulated data were validated. In the analysis, the simplification techniques for the numerical simulation were employed under the following two assumptions. The pressure distribution behind the wide dike was estimated using the axisymmetric flowfield, and the back step model was applied under the small condition for θ, the angle formed by the ground and the line between the explosion core and the dike front corner. From the simulated results, it is clarified that the large θ provided the great reduction of the blast wave pressure at faraway position. In the small θ condition, the conditions of the dike end position and the dike height were significant parameters determining the magnitude of pressure reduction and mitigated area. The pressure reduction at the dike end and mitigated area were predicted numerically, and related to the dike conditions. 相似文献
25.
Takamitsu Otake Yoshie Aoyagi Mayumi Matsuo Nobuyasu Itoh Takashi Yarita 《Journal of environmental science and health. Part. B》2013,48(5):390-394
The aim of to evaluate efficiency of this study was extraction pressurized liquid extraction (PLE) for the analysis of four pesticides, fthalide, etofenprox, fenitrothion, and isoprothiolane, in unpolished rice by comparing with homogenization as a reference technique. The concentrations of four selected pesticides obtained by PLE with acetonitrile at 130°C for 10 min × 2 cycles were comparable to those by homogenization with water-soaking. The repeatability of the analysis, represented as relative standard deviations (RSDs), were 1.4–3.6% (n = 3) for PLE at 130°C and 1.2–3.8% (n = 3) for homogenization with water-soaking. Recovery yields of surrogates were 75–88% and 87–109% for PLE at 130°C and homogenization with water-soaking, respectively, and these were satisfactory according to the method of positive list. This study suggested that PLE can be applied for the analysis of selected four pesticides in unpolished rice as well as homogenization with water-soaking. 相似文献
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Hwang In-Hee Matsuo Takayuki Matsuto Toshihiko Tojo Yasumasa Sameshima Ryoji 《Journal of Material Cycles and Waste Management》2021,23(4):1609-1616
Journal of Material Cycles and Waste Management - Sodium bicarbonate is among the alkali chemicals used for dry scrubbing in incineration flue gas treatment. It is generally pulverized into fine... 相似文献
30.
H.J. Kim D. Endo M. Sato T. Matsuo T. Matsuto 《Waste management (New York, N.Y.)》2009,29(8):2308-2315
Leachate accumulated at the Nakazono Landfill in Asahikawa, Japan due to an inadequate leachate collection and drainage system. To reduce the level of leachate in the landfill and promote the stabilization of waste, many passive gas vents were installed in addition to leachate collection vaults. This study evaluated the distribution and movement of leachate in the landfill by measuring leachate levels and conducting tracer tests in the gas vents.Water levels varied widely among gas vents and depended mainly on the vent’s original ground level and depth. Leachate velocity varied greatly; it was high in the upper layers of the saturated zone in a gas vent, but this was only a superficial velocity caused by inflow from unsaturated layers. A sharp decrease in total organic carbon observed in most gas vents after installation was likely due to the effect of aerobic biodegradation in the unsaturated waste layer. This effect was limited to a small aerobic zone around the gas vent. 相似文献