Vol. 55 No. 11
November, 2006
Junpei Kamada1, Katsuro Anazawa2, Hayao Sakamoto2 and Takashi Tomiyasu2
1 Course of Earth and Environmental Sciences, Graduate School of Science and Engineering, Kagoshima University, 1-21-35, Korimoto, Kagoshima-shi, Kagoshima 890-0065(Received 14 April 2006, Accepted 12 September 2006)
Considering the significance of possible future problems regarding water quality, it becomes important to obtain accurate and precise data on environmental water samples. For any uses of chemical data in water samples, it is important that measured data satisfy specified levels of reliability. A comparison between calculation and measurement of the electrical conductivity is widely applied to evaluate analytical reliability of wet deposition as well as cation and anion balance. However, because of the high ionic strength, the calculation method of the electrical conductivity for the wet deposition may not be applicable for land water samples, such as river or lake water samples. In this paper, the relation between the measured and calculated electrical conductivity will be discussed. The purpose is to propose a suitable evaluation method of the analytical reliability for land water samples.
Keywords : land water; electrical conductivity; QA/QC; infinite dilution.
Makoto Takada1, Tatsunori Sugawara1, Keiji Yoshimura1, Ryoei Kikuchi1, Takashi Kimoto2, Toru Ozeki3, Masahiro Kajikawa1 and Nobuaki Ogawa1
1 Faculty of Engineering and Resource Science, Akita University, 1-1, Tegata Gakuen-cho, Akita-shi, Akita 010-8502(Received 31 March 2006, Accepted 27 September 2006)
Fog water was collected at Mt.Hachimantai, Akita, in Northern Japan. The ionic components in the fog water were analyzed. Though it is well-known that ionic pollutants in air mass are taken in by fog droplets, in this work, the effects of the wind speed on the ion concentration were investigated. As a result, it was found that the ion concentrations of natural fog tended to increase or decrease with increasing in wind speed, depending on a meteorological conditions during an anticyclone or a cyclone. This difference of tendencies would be caused by the effects of an ascending current in a cyclone (diffusion of pollutants) or a descending current in an anticyclone.
Keywords : natural fog; wind speed; anticyclone; cyclone.
Shu-ichi Tamura1, Akiko Hokura1, Masahiro Oishi2 and Izumi Nakai1
1 Department of Applied Chemistry, Faculty of Science, Tokyo University of Science, 1-3, Kagurazaka, Shinjuku-ku, Tokyo 162-8601(Received 5 July 2006, Accepted 3 October 2006)
The measurement conditions for the precise analysis of the lead stable isotope ratio by using an ICP-MS equipped with a quadrupole mass spectrometer were studied in order to apply the technique to the forensic identification of bullet samples. The values of the relative standard deviation obtained for the ratio of 208Pb/206Pb, 207Pb/206Pb and 204Pb/206Pb were lower than 0.2% after optimization of the analytical conditions, including the optimum lead concentration of the sample solution to be about 70 ppb and an integration time for 1 m/z of 15 s. This method was applied to an analysis of lead in bullets for rifles and handguns; a stable isotope ratio of lead was found to be suitable for the identification of bullets. This study has demonstrated that the lead isotope ratio measured by using a quadrupole ICP-MS was useful for a practical analysis of bullet samples in forensic science.
Keywords : bullet samples; lead Isotope ratio analysis; forensic identification; quadrupole ICP-MS.
Masayuki Kunugi1, Kazuo Fujimori2 and Takeshi Nakano2
1 National Institute for Environmental Studies, 16-2, Onogawa, Tsukuba-shi, Ibaraki 305-8506(Received 25 April 2006, Accepted 10 August 2006)
We have developed the monitoring systems for marine pollution with higher flexibility in sampling station and time by using merchant vessels and by developing on automated sampling system in order to clarify the spatial and temporal variations and chemodynamics of hazardous chemicals in seawater on a global scale. Automated sampling systems were installed in both a crude carrier transporting from the Persian Gulf to Japan and a balk carrier from Australia to Japan, which observed hazardous chemicals. We had investigated the recovery rate of poly-urethane foam (PUF), active carbon fiber filters (ACF), and its composite type for solid-phase extracting materials. For measuring of persistent organic pollutants, large amounts of seawater (100~300 l) were passed through columns containing a solid phase extractor. Because of detection limits of HCHs and chlordanes were 1 pg/l and 3 pg/l, respectively, our system will be adaptable to observation of the open sea. We detected HCHs and chlordanes from many samples on these shipping lanes, and isomer patterns and spatial distributions of HCHs were characteristic.
Keywords : POPs; marine pollution; VOS; chemodynamics; global scale.
Shigeo Aoyagi1,4, Yousuke Utsumi1, Masaaki Matsudaira1, Hiroshi Yamada2, Masayuki Kacchi3, Hitoshi Shiku4, Hiroyuki Abe5, Hiroyoshi Hoshi3 and Tomokazu Matsue4
1 Hokuto Denko, 3028, Uenohara, Kamiechi, Atsugi-shi, Kanagawa 243-0801(Received 18 May 2006, Accepted 3 August 2006)
The quality of in vitro-produced bovine embryos was investigated by a scanning electrochemical microscopy (SECM)-based instrument for measuring the respiratory activity of individual bovine embryos. The measurement was performed by using a measuring cell equipped with a six cone-shaped microwell, a temperature-controlling unit, an auto-approach program to non-invasively locate the probe-microelectrode very close to the sample bovine embryo, a program for semi-automatic probe-scanning, and analyzing software to estimate the respiration activity of a single bovine embryo based on a spherical diffusion theory.
Keywords : quality evaluation; measuring respiration; bovine embryo; respiration rate.
Noboru Ebihara1, Tetsuo Uchida2, Hisako Ogura3 and Koichi Oguma4
1 Chiba Industrial Technology Research Institute, 889, Kasori-cho, Wakaba-ku, Chiba-shi, Chiba 264-0017(Received 23 May 2006, Accepted 4 August 2006)
A simple and complete decomposition method has been developed for the determination of trace elements in marine planktons using a pressurized decomposition vessel. Planktons were filtered through a PTFE filter and washed with an ammonium formate solution. After drying, the filter adhering planktons was weighed into a PTFE decomposition vessel with a stainless-steel jacket for digestion using a mixture of nitric, perchloric and hydrofluoric acids at elevated temperature. The sample solution was evaporated to dryness, and the residue was taken up with hydrochloric acid for the determination of metals by ICP-AES. Ethanol washing brought about plasmoptysis and yielded samples for the determination of trace elements in exoskeltons. The planktons collected in Tokyo Bay contained iron, aluminum, titanium, manganese, zinc, copper and chromium of 104 - to 106 - fold concentrations compared with those in seawater.
Keywords : marine planktons; complete decomposition; determination of trace elements.
Yoichi Namiki1, Masayoshi Takano1 and Masahiro Yoneno1
1 Henkel Japan Ltd., 27-7, Shin Isogo-cho, Isogo-ku, Yokohama-shi, Kanagawa 235-0017(Received 30 May 2006, Accepted 31 August 2006)
A new method to measure the curing conversion of condensation-curable one-component silicone rubber by determining the area of a very small absorption peak of the infrared spectrum recorded with an ATR-IR spectrometer has been investigated. Condensation curing of silicone causes a increase of the absorption band of silanol on 960~810 cm-1. However, this absorption peak is actually very small and overlaps a prominent neighboring peak, and is difficult to be identified quantitatively. In this study, to remove this interference of the prominent peak, the spectrum of a fully cured sample was applied for subtraction from each sample's spectrum to convert the bent baseline into a straight horizontal line. Furthermore, by a technique of removing the internal standard peak from the spectrum of a fully cured sample before subtraction, the internal standard peaks remain on the spectra after subtraction, and are applied for normalization to remove any measurement errors. By this method, a curing conversion of condensation curable one-component silicone rubber can be determined rapidly and non-destructively.
Keywords : silicone; silanol; conversion; ATR.
Minemasa Hida1, Hiroyasu Satoh1, Syuji Okuyama1 and Toshiyuki Mitsui2
1 Criminal Investigation Laboratory, Aichi Prefectural Police H.Q., 2-1-1, Sannomaru, Naka-ku, Nagoya-shi, Aichi 460-8502(Received 30 May 2006, Accepted 8 September 2006)
Forty liquid gasoline samples and extracts from forty-seven combustion residue samples were calculated from multiple regression coefficients (R) against two kinds of marketing gasolines as references with different calculation methods of the regression analysis by using 12 components that eluted after xylene. A quantitative evaluation for heat degradation of the samples was performed with the R values. If a sample R value of more than 0.85 was obtained, we could judge whether the sample was a gasoline only from a gas chromatogram. For sample R values from 0.85 to 0.50, additional information was required to judge whether the samples were gasoline. A sample R value of less than 0.5 clearly showed that it was not gasoline. This method was tried to apply a difference discrimination using both one subject sample and one object sample. We could prove that the subject and the object samples were the same kind of gasoline if the calculated R value was 0.999 or more.
Keywords : gasoline; multiple regression coefficient; different calculation method of regression analysis (DCR); heat degradation; criminal research.
Akira Kawase1, Kazuo Ohashi1, Isoko Akabane1, Takayoshi Kuroiwa1, Mariko Murayama1, Hajime Yoshimura1, Jun Yoshinaga1, Michihisa Uemoto1, Akihiro Ono1, Kazutoshi Kakita1 and Mamoru Sakata1
1 The Japan Society for Analytical Chemistry, 1-26-2, Nishigotanda, Shinagawa-ku, Tokyo 141-0031(Received 27 January 2006, Accepted 26 June 2006)
The Japan Society for Analytical Chemistry has developed new certified reference materials (CRMs) (JSAC 0301-1, JSAC 0301-2, JSAC 0302) for the analysis of 18 elements in river water. A study team has been organized to prepare two kinds of water for reference materials: one is natural river water, and the other is water spiked with small amounts of some elements to the river water. Interlaboratory testing, in which 30 laboratories participated, was carried out. In a statistical analysis of all data, z scores in a robust method were applied to reject outliers, followed by the usual statistical procedure.
Keywords : river water; certified reference material; inorganic components; interlaboratory testing.
Tomoko Nakano-Ohta
Department of Nuclear Science and Engineering, Research Reactor Institute, Kyoto University,
2, Asashironishi, Kumatori-cho, Sennan-gun, Osaka 590-0494
(Awarded by Meiji University dated March 26, 2006)
A variation of the 228Ra/226Ra activity ratio of underground water suggested a monotonous decrease along with an increase in the residence time within an aquifer. Observation with hot-spring water samples showed that the 228Ra/226Ra activity ratios in water from deeper aquifers with longer residence times tended to be smaller than those in river waters with a shorter residence time. The residence time of Kakita-gawa river water, estimated from the 228Ra/226Ra activity ratios of river water and relevant rock, agree well with the 3H-3He age, suggesting that the 228Ra/226Ra activity ratio of underground water could be used as a tool for a residence-time estimation of underground water. The 228Ra/226Ra activity ratios in the river-water sample showed that the activity ratios tended to decrease after heavier rainfall. The decrease suggested that heavy rainfall forced deeper underground water with a long residence time to discharge into river. The variation of the monthly averaged concentration of 222Rn in underground water was similar to that of precipitation. The variation pattern suggested that precipitation may give rise to the mixing of underground water components of different origins, which is consistent with the consideration that heavy rainfall forced the deeper underground water to discharge into the river.
(Received July 20, 2006)
Keywords : Ra-226; Ra-228; 228Ra/226Ra activity ratio; river water; 222Rn; underground water; Mn-impregnated acrylic fiber.
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