خيارات البحث
النتائج 21 - 30 من 109
Determination of aliphatic lower amines in environmental samples
1999
Tsukioka, T. (Nagano-ken. Research Inst. for Health and Pollution (Japan))
A micro analytical method has been established for aliphatic lower primary and secondary amines in environmental water and sediment. Amines were distilled and allowed to react with benzenesulfonyl chloride under an alkaline condition. The derivatized compounds were extracted with benzene under an acidic condition and subjected to a determination by GC/MS. This method has been successfully applied for a simultaneous determination of primary and secondary amines with recovery over 80%, except for methylamine, and C.V. below 7%, except for methyl and dimethyl amines; moreover, the detection limit were 0.1 micro g/L for all of the amines determinated. This method is excelent also in sensitivity, is sufficiently applicable to environmental samples.
اظهر المزيد [+] اقل [-]Survey of chemical substances in freshwater fish
1999
Terasawa, J. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Miyagawa, A. | Tsukioka, T. | Sato, M.
Behavior of airborne halocarbons in urban and highland areas of Nagano prefecture [Japan]
1999
Sasai, H. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Katsuno, T. | Nomizo, H. | Satsumabayashi, H.
Direct aqueous derivation and gas chromatographic analysis of halogenated lower carboxylates in environmental samples
1997
Ozawa, H. (Nagano-ken. Research Inst. for Health and Pollution (Japan))
Analytical method for hydrophilic polar environmental pollutants was studied. Among these pollutants, the halogenated lower carboxylates were the target compounds of this investigation. A novel but simple derivatization method necessary for sample preparation for instrumental analysis was developed. The new derivatization method for the carboxylates is not a conventional chemical reaction in non-aqueous solvent following isolation from the environmental samples but rather, a direct aqueous reaction ; direct conversion of the carboxylates to amides using a carbodiimide in dilute aqueous solution. Halogenoanilines were selectively used with dicyclohexylcarbodiimide (DCC) under acidic conditions at room temperature to form the anilide derivatives. Moreover, this reaction proceeds while mixing the sample water, DCC, a halogenoaniline, and small volume of extracting solvent. Thus, for the first time, simultaneous derivatization of the carboxylates and extraction of the products into solvent was achieved. Based on the results, simple and practical determination methods by gas chromatography were developed for traces of these carboxylates in environmental samples and the proposed methods were applied to some real samples. Such analytical derivatization methods for carboxylates are useful and noteworthy because they can form C-N bonds in aqueous media under mild conditions with carbodiimides and N atoms of amino and other compounds.
اظهر المزيد [+] اقل [-]Survey of river water acidification in Nagano prefecture [Japan]
1997
Miyajima, I. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Katsuno, T. | Takeda, Y. | Shiozawa, K.
Characterization of heavy metals in ashes from mixed refuse
1994
Hayashi, H. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Nomura, Y. | Itoh, S. | Maruyama, M.
In order to ascertain the characterization of heavy metals in ashes from mixed refuse, the composition of those carried in A, B and C incineration facilities in Nagano prefecture was classified into 6 kinds of wastes and the amount of heavy metals, namely Cd, Pb, Cu, Zn, Ni, Mn and Fe, contained in residual ashes were studied. The different pattern of the waste composition found in B facility showed indirectly the special system of the waste treatment at the region. As compared with others, the concentration of Cd, Pb, Cu, Zn and Ni in ashes from plastics waste tended to high. The contributions of each combustible component against the total amounts of each heavy metal derived from mixed refuse were also shown.
اظهر المزيد [+] اقل [-]Comparison of epidemiological markers of Salmonella Enteritidis isolated from food poisoning in Nagano prefecture [Japan]
1994
Muramatsu, K. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Yamagishi, T.
A comparative study of the phagovars, antimicrobial susceptibility patterns, and plasmid profiles of 119 strains of Salmonella Enteritidis isolated from food poisoning was carried out to determine the most adequate markers in epidemiological investigations. An epidemiological pattern (consisting of a phagovar 4 and 60kb plasmid) emerged as the predominant pattern in Nagano prefecture during the study period.
اظهر المزيد [+] اقل [-]Pattern analysis of offensive-odor substances in young salmon [Oncorhynchus masou] by gas chromatography and mass spectroscopy
1989
Taguchi, Y. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Yamaura, Y. | Tsukioka, T. | Hayashi, H. | Seki, H. | Maki, S.
The isolation of Campylobacter and Salmonella from the healthy dogs and cats in Nagano prefecture
1987
Muramatsu, K. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Sasai, S. | Wada, M. | Miyasaka, T.
During the period from 1981 to 1986, Campylobacter and Salmonella were isolated from healthy dogs and cats by the Nagano Prefecture Dog Pound Office. Campylobacter was isolated from 35 (7.0%) dogs out of 497 and 14 (10.1%) cats out of 138. Salmonella was isolated from 38 (7.6%) dogs out of 497, but not isolated from cats. The frequency of the isolation of Salmonella in puppies (under one year old) was about 2 times higher than that of adult dogs. A total of 42 strains of Salmonella was isolated from the dogs, and it was typed into 15 serovars. S. infantis, S. agona, S. anatum and S. paratyphi B, d- tartrate(+) were the most frequent serovars. Isolated Campylobacter strains were identified as C. jejuni (48 strains) and C. colt (1 strain). Considering these results, we were suggested that dogs and cats may act as possible sources of Campylobacter and Salmonella infection in human.
اظهر المزيد [+] اقل [-]Investigation on release of nitrogen and phosphorus from the sediments of different depth in Lake Suwa [Japan]
1987
Kono, Y. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Terasawa, J. | Harada, T. | Nasu, Y. | Kugimoto, M.
For the purpose of determining the effect of dredging on nutrients releasing from the sediment at the bottom of Lake Suwa after some of its sediment has been dredged, an experiment was performed to find out how much ammonium and phosphate would release from different depths of the sediment. Lake Suwa's sediment contains a lot of nitrogen and phoshorus down to its lower layers. The results of the experiment were as follows: The speed at which ammonium released from was faster as the depth of sediment increased. The speed at which ammonium was generated in the sediment showed the highest of 2.58N micro g/g dry sediment d in a 0-10cm layer. However, ammonium showed a generation speed of 1.3-1.4N micro g/g dry sediment-d at the depth of 10cm and more, indicating that ammonium easy to release from is generated even in lower layers. The speed at which phosphorus released from was 1.3-1.7Pmg/square m d in a 0-20cm deep layer, and 0.14-0.31Pmg/square m d at the depth of 20cm and more. The speed of Phosphorus releasing from lower layers of the sediment decreased to 1/4-1/10 of that in upper layers, and it was indicated that very little phosphorus flows out of the sediment at the depth of 20cm and more.
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