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71.
This paper provides an overview of the main features of irrigation in Japan, and the issues it raises, rather than an exhaustive survey of the subject. The authors’ remarks concentrate on irrigation for rice cultivation, since irrigation for non‐paddy crops is not widely developed and claims a very minor share of the country's water resources. The main components of the water requirements of rice irrigation are identified, and then the composition and functions of farmers’ irrigation associations, or more correctly ‘land improvement districts’, are described. 相似文献
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In order to establish a new method for simultaneous determination of sulfated bile acids without deconjugation, separation
of 3-sulfates of unconjugated, glyco- and tauroconjugated bile acids by high-performance liquid chromatography has been undertaken.
The preliminary experiment indicated that reversed phase chromatography on an ODS SC-02 column using ammonium carbonate aqueous
solution/acetonitrile as a mobile phase would be promising. The ratio of peak width to retention time was varied depending
upon the salt concentration. The content of water in mobile phase exerted an influence on the capacity ratio to a certain
extent, but not on the resolution. The use of 0.5% ammonium carbonate/acetonitrile (26∶8 and 20∶8, v/v) was found to be suitable
for complete resolution of sulfated cholate, chenodeoxycholate, deoxycholate, lithocholate and their glyco- and tauro-conjugates. 相似文献
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Using a new temperament inventory (the Japanese Temperament Questionnaire) developed from the free response of Japanese mothers asked to describe their infants' behavioral styles, mothers (N?=?469) rated behaviors observed in their 1-, 3-, or 6-mo-old baby. The ratings were factor analyzed and the dimensions generated by the factor analysis were labeled by an independent maternal group. Results support the conclusions that mothers' perceptions of infant temperament were both pancultural and culture specific. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
Masato Takeuchi Junichi Deguchi Manabu Hidaka Shiro Sakai Kyoungja Woo Pyuck-Pa Choi Jong-Ku Park Masakazu Anpo 《Applied catalysis. B, Environmental》2009,89(3-4):406-410
The photocatalytic oxidation of gaseous acetaldehyde with O2 on commercial TiO2 nano-particles could be successfully enhanced by a simple mechanical blending with a high-silica mordenite (MOR) zeolite, the surface of which showed high hydrophobic properties. When the TiO2 nano-particles of ca. 5–20 wt% were mixed with the MOR zeolite powders in an agate mortar for only 5 min, the blended TiO2/MOR samples showed higher photocatalytic reactivity as compared to the pure TiO2 nano-particles. Since the high-silica zeolite powders are highly transparent in UV light regions, the incident UV light is effectively irradiated onto the whole part of the TiO2 nano-particles without any loss of light intensity. Furthermore, the siliceous MOR zeolite powders effectively adsorb the gaseous acetaldehyde molecules and supply them onto the surfaces of the blended TiO2 nano-particles, resulting in an enhancement of the photocatalytic reactivity. 相似文献
80.
Pseudomonas aeruginosa as a model microorganism for investigation of chemotactic behaviors in ecosystem 总被引:1,自引:0,他引:1
Kato J Kim HE Takiguchi N Kuroda A Ohtake H 《Journal of Bioscience and Bioengineering》2008,106(1):1-7
Motile bacteria sense changes in the concentration of chemicals in environments and respond in a behavioral manner. This behavioral response is called chemotaxis. Bacterial chemotaxis can be viewed as an important prelude to metabolism, prey-predator relationships, symbiosis, infections, and other ecological interactions in biological communities. Genome analysis reveals that a large number of environmental motile bacteria possess a number of genes involved in chemosensing and chemotatic signal transduction. Pseudomonas aeruginosa has a very complex chemosensory system with more than 20 chemotaxis (che) genes in five distinct clusters and 26 chemoreceptor (methyl-accepting chemotaxis protein [mcp]) genes. Among the 26 MCPs of P. aeruginosa, nine have been identified as MCPs for amino acids, inorganic phosphate, oxygen, ethylene, and volatile chlorinated aliphatic hydrocarbons, whereas 3 MCPs were demonstrated to be involved in biofilm formation and biosynthesis of type IV pilus. Six che genes are essential for chemotactic responses, while genes in Pil-Chp cluster and Wsp cluster are involved in type IV pilus synthesis and twitching motility and biofilm formation, respectively. P. aeruginosa, with its complex chemotaxis system, is a better model microorganism for investigating ecological aspects of chemotaxis in environmental bacteria than Escherichia coli and Salmonella enterica serovar Typhimurium, which possess a relatively simpler chemotaxis system. 相似文献