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21.
Koki Sato Kazuya Yamamoto Jun-ichi Kadokawa 《Journal of Polymers and the Environment》2018,26(9):3540-3549
In this study, we investigated the preparation of cationic/anionic chitin nanofiber (CNF) composite materials by electrostatic interaction. An aqueous dispersion of amidinium CNF was prepared by a top-down approach, and a maleylated CNF film was obtained by a bottom-up approach from a chitin ion gel in an ionic liquid with subsequent maleylation on the CNFs. The resulting film was dispersed in ammonia (aq), which was then mixed with the aqueous cationic CNF dispersion to give the composite film. The composition of the two CNFs was evaluated by scanning electron microscopy and X-ray diffraction measurements. Tensile testing results indicated that the mechanical properties of the composites were enhanced with increasing degrees of substitution of the cationic and anionic groups on CNFs, and also when the molar ratio of these groups approached 1:1. The dissociation of the two kinds of CNFs by alkaline treatment of the composite film was achieved, suggesting the presence of an electrostatic interaction among the interactions between them. 相似文献
22.
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
23.
Knighton WB Herndon SC Shorter JH Miake-Lye RC Zahniser MS Akiyama K Shimono A Kitasaka K Shimajiri H Sugihara K 《Journal of the Air & Waste Management Association (1995)》2007,57(11):1370-1378
We demonstrate the use of an aldehyde scrubber system to resolve isobaric aldehyde/alkene interferences in a proton transfer reaction mass spectrometer (PTR-MS) by selectively removing the aldehydes from the gas mixture without loss of quantitative information for the alkene components. The aldehyde scrubber system uses a bisulfite solution, which scrubs carbonyl compounds from the gas stream by forming water-soluble carbonyl bisulfite addition products, and has been evaluated using a synthetic mixture of acrolein and isoprene. Trapping efficiencies of acrolein exceeded 97%, whereas the transmission efficiency of isoprene was better than 92%. Quantification of the PTR-MS response to acrolein was validated through an intercomparison study that included two derivatization methods, dinitrophenylhydrazine (DNPH) and O-(4-cyano-2-ethoxybenzyl)hydroxylamine (CNET), and a spectroscopic method using a quantum cascade laser infrared absorption spectroscopy (QCL) instrument. Finally, using cigarette smoke as a complex matrix, the acrolein content was assessed using the scrubber and compared with direct QCL-based detection. 相似文献
24.
Seasonal variation in the atmospheric deposition of inorganic constituents and canopy interactions in a Japanese cedar forest 总被引:1,自引:0,他引:1
Sase H Takahashi A Sato M Kobayashi H Nakata M Totsuka T 《Environmental pollution (Barking, Essex : 1987)》2008,152(1):1-10
The seasonal changes in throughfall (TF) and stemflow (SF) chemistry and the canopy interactions of K+ and N compounds were studied in a Japanese cedar forest near the Sea of Japan. The fluxes of most ions, including non-sea-salt SO4(2-), from TF, SF, and rainfall showed distinct seasonal trends, increasing from autumn to winter, owing to the seasonal west wind, while the fluxes of NH4+ and K+ ions from TF+SF might have a large effect of canopy interactions. The contact angle (CA) of water droplets on leaves decreased with leaf aging, suggesting that surface wettability increases with leaf age. The K+ concentration in TF was negatively correlated with the CA of 1-year-old leaves, while the NH4+ concentration was positively correlated with the CA. The net fluxes of NH4+ and NO3(-) from TF were positively correlated with the CA. The increase in wettability may accelerate leaching of K+ or uptake of NH4+. 相似文献
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27.
Mengqian Lu Bin-Le Lin Kazuya Inoue Zhongfang Lei Zhenya Zhang Kiyotaka Tsunemi 《Frontiers of Environmental Science & Engineering》2018,12(2):13
Ammonia has emerged as a promising hydrogen carrier with applications as an energy source in recent years. However, in addition to being toxic, gaseous ammonia is a precursor of secondary inorganic aerosols. The concentration of ambient fine particulate matter (PM2.5) is intrinsically connected to public health. In this study, PM2.5-related health impacts of utilizing ammonia-hydrogen energy in Kanto Region, Japan, were investigated. It was assumed that 20% of the electricity consumption in Kanto Region, the most populated area in Japan, was supplied by ammonia-hydrogen energy. The PM2.5 resulted from incomplete ammonia decomposition was simulated by a chemical transport model: ADMER-PRO (modified version). Based on the incremental PM2.5 concentration, health impacts on the elderly (individuals over 65 years old) were quantitatively evaluated. The ammonia emission in this scenario increased PM2.5 by 11.7% (0.16 μg·m–3·y–1) in winter and 3.5% (0.08 μg ·m–3·y–1) in summer, resulting in 351 premature deaths per year. This study suggests that costeffective emissions control or treatment and appropriate land planning should be considered to reduce the associated health impacts of this type of energy generation. In addition, further in-depth research, including cost-benefit analysis and security standards, is needed.
相似文献
28.
Guido Plaza Hideo Sakaji Hitoshi Honda Yuichi Hirota Kazuya Nashida 《Marine Biology》2007,152(5):1051-1064
Spawning pattern (assessed by seasonal changes in ovarian developmental stages) and type of fecundity (assessed by analysis
of oocyte-size frequency distributions) of the round herring Etrumeus teres were studied in relation to ovarian growth and seasonal changes in the gonadosomatic (GSI), hepatosomatic (HSI) and liposomatic
(LSI) index as well as the somatic condition of spawners (CS) in a spawning ground of southern Japan. Except for summer, mature
and recently spawned ovaries occurred all year round. Oogonia and primary oocytes were present in all ovaries, and cortical
alveoli stage (CA) oocytes occurred in all mature, hydrated and partially spent (PS) females (PS: females containing post-ovulatory
follicles). Before hydration, a clutch of larger yolked oocytes, undergoing synchronous growth (range 0.7–1.1 mm), was present
in mature ovaries which was completely separated from a more heterogeneous clutch of oogonia, primary and secondary oocytes
(<0.150 mm) and oocytes in the CA stage (range 0.15–0.60 mm). As vitellogenesis progressed, the yolked clutch increased in
size but the CA oocytes remained arrested. The latter entered into the secondary growth phase when hydration started in the
advanced batch. Ovarian growth was isometric in all developmental stages, validating the use of GSI, which showed a consistent
monthly evolution among years. Spawning stopped in summer (July and August) and peaked in winter and spring. HSI correlated
positively with GSI on both a monthly mean basis (r = 0.76) and individual fish basis (liver weight explained 67–83% of the variability in ovary weight when females were grouped
into 1-unit GSI intervals) suggesting a significant role of liver in vitellogenesis. LSI and CS also showed marked seasonal
changes peaking from summer to middle autumn. Overall results suggest that E. teres is a multiple spawner with a group-synchronous ovarian development and indeterminate annual fecundity, with the three processes
linked to an isometric growth of the ovary. We propose that such a reproductive pattern is an adaptation to produce batches
of large pelagic eggs through a protracted spawning season. 相似文献
29.
Kazuya Yasuhara Hideo Komine Hiromune Yokoki Takeshi Suzuki Nobuo Mimura Makoto Tamura Guangqi Chen 《Sustainability Science》2011,6(2):219-232
Humanity faces an increasing possibility that unusual and extreme natural disasters will increase, compounded with climate
change, including global warming. These compound events are designated as compounded natural hazards in this study. A methodology
must be developed for predicting what events and risks will confront future societies, to propose countermeasures and adaptation
strategies against these events, and to evaluate the influences of compound disasters on infrastructure which is particularly
situated near coasts and rivers. Based on the above-stated background and demands, this study was undertaken with the intention
of upgrading the methodology for estimating effects on infrastructure of compound events such as increased typhoon and rainfall
severity caused by global warming occurring concurrently with a great earthquake in Japan. Such a methodology is expected
to contribute to progress in the fields of natural disaster mitigation and land preservation, particularly benefiting coastal
and river areas in Japan. Additionally in this study, risk and economic loss analyses for the possible occurrence of compound
disasters for coastal infrastructure and foundations are produced for establishing environmental strategies at the governmental
level. The authors further propose adaptation strategies and techniques as countermeasures against these events. 相似文献
30.
T. Yamada T. Inoue H. Fukuhara O. Nakahara T. Izuta R. Suda M. Takahashi H. Sase A. Takahashi H. Kobayashi T. Ohizumi T. Hakamata 《Water, Air, & Soil Pollution: Focus》2007,7(1-3):259-266
Since 1983, the Ministry of the Environment of Japan has conducted nation-wide acid deposition surveys. To investigate the
effects of acid deposition on surface water, we used the nonparametric Mann–Kendall test to find temporal trends in pH, alkalinity,
and electrical conductivity (EC) in more than 10 years of data collected from five lakes and their catchments (Lake Kuttara:
northernmost; Lake Kamakita: near Tokyo; Lake Ijira: central; Lake Banryu: western; and Lake Unagiike: southernmost). The
pH of Lake Ijira water has declined slightly since the mid-1990s, corresponding with the downward trends seen in the pH and
alkalinity of the river water flowing into the lake. There were significant upward trends in the EC of both the lake and stream
water; the same trends were also found for concentrations. These trends show evidence of acidification due to atmospheric deposition, and this is the first such finding
in Japan based on significant long-term trends. Lake Ijira is located about 40 km north of the Chukyo industrial area near
Nagoya. The annual depositions of H+, nss-, and in Lake Ijira were among the highest of all deposition monitoring sites, suggesting that this is the main cause of the significant
acidification observed in Lake Ijira. No significant trends suggesting acidification were observed in any of the other lake
catchments in spite of the significant upward trends in EC. Upward trends in pH and alkalinity at Lake Banryu and upward trends
in alkalinity at Lake Kamakita were detected, but no change in pH or alkalinity at Lake Kuttara and Lake Unagiike was observed. 相似文献