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Volume 64, Issue 8
Special Articles : The First Papers of Prospective Analytical Chemists
Displaying 1-10 of 10 articles from this issue
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Research Papers
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Dai YAMASAKI, Hidetaka KAJIWARA, Masataka KIRII, Shinichi OHIRA, Kei T ...Article type: Research Papers
2015 Volume 64 Issue 8 Pages 571-579
Published: August 05, 2015
Released on J-STAGE: September 03, 2015
JOURNAL FREE ACCESSIn order to establish a simple and highly sensitive analytical method, thermal desorption followed by gas chromatography/mass spectrometry (TD-GC/MS) was investigated for polycyclic aromatic hydrocarbons (PAHs) in PM2.5. In this work, the TD condition was optimized for PAHs in filter samples, and the performance was compared with those by the solvent extraction method (SE). Even the TD method was much simpler, sensitivity is much higher compared to that of the SE method. TD-GC/MS was highly sensitive and PAHs could be detected with shorter sampling time. Accordingly, detailed seasonal variations were obtained with relatively shorter sampling time (1 – 3 days) for the long term. While the PM2.5 concentration changed in small ratio in different seasons, the PAH concentrations were much higher in the winter and spring when PAHs were largely emitted on the Chinese continent and transferred to Japan. The TD-GC/MS is highly sensitive, and a daily variation was obtained with a 4 h resolution. Furthermore the PAHs compositions emitted in the field burning could be determined just by sampling the air by driving a car for a half an hour through the burning grass field. The ratio of low molecular PAHs (3 – 4 rings) was higher in the field burning sample compared to those in PM2.5 sampled in Kumamoto-city for days. The TD-GC/MS is superior in both analytical cost and performance, and is expected to be used for many applications in atmospheric analysis and air monitoring.View full abstractDownload PDF (2104K) -
Keigo SHINDO, Naoya KISHIKAWA, Kaname OHYAMA, Naotaka KURODAArticle type: Research Papers
2015 Volume 64 Issue 8 Pages 581-587
Published: August 05, 2015
Released on J-STAGE: September 03, 2015
JOURNAL FREE ACCESSParaquat and diquat are most widely used herbicides, but they have significant acute toxicity to humans. The aim of the present study is to develop a high-performance liquid chromatography (HPLC)-chemiluminescence (CL) detection system that allows simultaneous determinations of paraquat and diquat. The proposed HPLC-CL method is useful to evaluate health risk and origin of paraquat and diquat. Paraquat and diquat are separated by silica-gel HPLC, and CL detection is based on the luminol-detecting CL of superoxide anion radicals, which are generated by the redox cycle reaction between paraquat or diquat and dithiothreitol. Under the optimum conditions, paraquat and diquat were detected at 16.0 and 13.0 min, respectively, and the limit of detection (S/N = 3) was 40 nM for paraquat and 53 nM for diquat. Using the proposed HPLC-CL method, the peaks corresponding to paraquat and diquat in human plasma could be selectively detected on chromatograms without any interference from plasma components by simple deproteinization with 50% trichloroacetic acid.View full abstractDownload PDF (1007K) -
Ko NAKAMACHI, Masaaki HIROSE, Yoshikazu KIKAWADA, Katsumi HIROSE, Yuki ...Article type: Research Papers
2015 Volume 64 Issue 8 Pages 589-594
Published: August 05, 2015
Released on J-STAGE: September 03, 2015
JOURNAL FREE ACCESSThe Fukushima daiichi nuclear power plant (FDNPP) was seriously damaged by the huge earthquake and subsequent tsunami on 11 March 2011, and has released large amounts of radioactive materials into the environment. Since the accident, radioactive cesium originating from the FDNPP accident was detected over a wide range of the northeastern half of Honshu, the main island of Japan, including the Kanto region. The long-term monitoring of the activities of FDNPP-derived radioactive cesium in surface air must provide important knowledge concerning the dispersion processes of radioactive cesium and its supply to the atmosphere. In this study, we focused on airborne particulate matters (APM) collected at Kawasaki city, Kanagawa. The aim of this study was to obtain the time series date of radioactive cesium activities and to characterize the chemical properties of radioactive cesium in the APM. Consequently, we obtained the following information. Until the spring of 2014, both of the FDNPP-derived 134Cs and the 137Cs activities in the APM, which were still detected, decreased to ca. 10−5 times those observed just after the FDNPP accident. Specifically, their activities decreased rapidly until September, 2011, and then their decrease rates slowed down. Sequential leaching experiments revealed that the chemical properties of radioactive cesium in the APM differed from those in soil; significant amounts of radioactive cesium in the AMP existed as a water-soluble form, whereas most of the radioactive cesium in soil was insoluble in water.View full abstractDownload PDF (1054K) -
Toshimitsu ARAKI, Tetsuo INUI, Toshihiro NAKAMURAArticle type: Research Papers
2015 Volume 64 Issue 8 Pages 595-600
Published: August 05, 2015
Released on J-STAGE: September 03, 2015
JOURNAL FREE ACCESSA solid sampling/graphite furnace atomic absorption spectrometry was developed for the determination of Dy in rock with a lithium tetraborate glass-bead technique. A 1 : 1 glass bead was prepared from a rock sample and lithium tetraborate flux for the cross-validation of the glass bead/X-ray fluorescence analysis, and then crushed into fine powder under 250 μm of particle size. The resulting powder was mixed with graphite powder at a ratio of 1 : 3 in an alumina mortar. A 1.0 – 2.0 mg portion of the mixture was weighed on a platform, inserted into a graphite tube, and atomized according to an optimized heating program. Dy was determined by using a calibration curve drawn with the glass bead powder of volcanic rock reference materials. The lifetime of the graphite tube and the platform were prolonged, and the integrated absorbance of Dy improved remarkably with the addition of graphite powder to glass bead powder. The coexistence of a large amount of lithium tetraborate caused a sensitizing effect to direct the atomization of Dy in rock. The calibration curve of Dy showed good linearity (r = 0.998) up to 1.4 ng, and the lower limit of detection was 0.07 ng, which corresponds to 0.28 ppm using 0.25 mg rock sample. Analytical values of Dy in plutonic rock reference materials showed good agreement with the reference values. The relative standard deviations (n = 5) of the proposed method were 6.6% for 9.4 ppm of Dy and 8.9% for 1.2 ppm of Dy in plutonic rock reference materials. The proposed method was useful for the cross-validation of glass bead/X-ray fluorescence analysis of Dy in granitic rock samples.View full abstractDownload PDF (850K) -
Kengo YAMANE, Yuuta HORIOKA, Masayuki FUJINO, Kazuaki ITOArticle type: Research Papers
2015 Volume 64 Issue 8 Pages 601-608
Published: August 05, 2015
Released on J-STAGE: September 03, 2015
JOURNAL FREE ACCESSThe simultaneous determination of six inorganic anions [iodate (IO3−), bromate (BrO3−), nitrite (NO2−), nitrate (NO3−), bromide (Br−), and iodide (I−)] in seawater was examined by ion chromatography (IC). The separation and detection of the anions were examined using a dodecylammonium chloride (DAC)-coated C18-silica column or a DAC-coated C18 polymer column (150 mm×4.6 mm i.d., each) and a concentrated aqueous NaCl solution containing 0.5 mM DAC and 5 mM phosphate buffer (pH 2.0 – 6.5) with ultraviolet detection (UV) at 225 nm. For DAC-coated C18-polymer column, separation was also examined for eluents of an alkaline solution (pH 7.0 – 10.0). For the DAC-coated C18-silica column, good separation and detection were obtained for all six anions in pure water and 35‰ artificial seawater without interferences from matrix ions such as chloride and sulfate. The anions were retained mainly on the DAC-coated C18 silica column through the anion-exchange properties and hydrogen bonding with the NH proton. On the other hand, the separation and detection were insufficient for the DAC-coated C18 polymer column. For optimized IC systems using the C18 silica column, good separation and detection for the anions in 35‰ artificial seawater were obtained within 25 min. NaCl in the eluent enhanced the DAC coating. The 0.5 mM DAC in the eluent helps to maintain the performance of the coated columns. Good repeatability [RSD<1.24% (n = 5)] for the retention time, peak height, and peak area and calibration curves (r2>0.999 for peak area method) were obtained for all of the anions. The detection limits (S/N = 3) with a 100 μL sample injection were 7.5 μg L−1 for IO3−, 17.3 μg L−1 for BrO3−, 83.2 μg L−1 for Br−, 0.73 μg L−1 for NO2−, 1.5 μg L−1 for NO3−, and 0.73 μg L−1 for I−. The present IC system was successfully applied to real seawater samples with recovery rates of 99 – 109% for all of the ions.View full abstractDownload PDF (963K)
Technical Papers
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Ayako URESHINO, Tetsuya SAWATSUBASHI, Akihiro NOZAKI, Senichi TSUBAKIZ ...Article type: Technical Papers
2015 Volume 64 Issue 8 Pages 609-615
Published: August 05, 2015
Released on J-STAGE: September 03, 2015
JOURNAL FREE ACCESSWe developed a concentration method using a double filter as a pre-treatment. We call it the "Double filter concentration method". It is a pre-treatment method for the determination of traces of iron by 2,4,6-tris(2-pyridyl)-1,3,5-triazine (TPTZ) absorption photometry. It is important to monitor iron concentration in an ultra-supercritical pressure boiler applying an oxygen treatment method as a water treatment. Because the iron in feedwater forms a hematite, it is necessary to control the iron concentration in the feedwater at less than 2 μg L−1 so as to prevent problems. Therefore, a quick and effective analysis method is necessary on site. The double filter is constructed in the membrane filter and chelate filter having iminodiacetic acid groups. Iron particles are trapped by the membrane filter, and the dissolved iron are trapped by the chelate filter. When we applied this developed method, we were able to measure the low range iron concentrations. This method is suitable for on-site analysis because it can also shorten the analysis time.View full abstractDownload PDF (1206K) -
Kana MIYOSHI, Yoshinari ABE, Yuichi TAKAKU, Izumi NAKAIArticle type: Technical Papers
2015 Volume 64 Issue 8 Pages 617-624
Published: August 05, 2015
Released on J-STAGE: September 03, 2015
JOURNAL FREE ACCESSThis paper reports on the behavior of rare-earth elements (REE) in plants studied by LA-ICP-MS. The REE distribution in the leaves of, ‘Athyrium yokoscense’, could be successfully visualized by LA-ICP-MS. The results showed that the LREE and HREE distributions in the leaf of Athyrium yokoscense exhibited two kinds of correlation, depending on the position of the leaf tissues. A semi-quantitative analysis of the REE distribution in a leaf was successfully carried out using in house standard samples prepared by employing cellulose powder.View full abstractDownload PDF (3905K)
Notes
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Tomohiro TAKEKAWA, Kentaro ISHII, Yoshinori NISHIWAKI, Keiji GAMOHArticle type: Notes
2015 Volume 64 Issue 8 Pages 625-630
Published: August 05, 2015
Released on J-STAGE: September 03, 2015
JOURNAL FREE ACCESSThis study has revealed that SR-XRF (synchrotron radiation X-ray fluorescence spectrometry) is a highly effective technique for forensic discrimination of automotive aluminum wheel fragments. After 47 automotive aluminum wheels were collected, those fragments with a size of less than 300 × 300 μm2 were used as analytical samples. Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Pb, Sr and Zr were detected from the small fragments. Comparisons of the samples were conducted based on the normalized X-ray intensities, which are X-ray intensities of these elements (Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Pb, Sr and Zr) normalized by those of Ga. All fragments could be discriminated using the normalized X-ray intensities. The normalized X-ray intensities could be useful as important indicators to discriminate samples. The normalized X-ray intensities were used in principal-component analysis to classify the automotive aluminum wheel fragments. As a result, the automotive aluminum wheel fragments could be divided broadly two groups according to the normalized X-ray intensities of Cu/Ga and Sr/Ga. It was found that the automotive aluminum wheel fragments contain rich elemental information for discrimination and, therefore, the materials can be important evidences for practical forensic examination.View full abstractDownload PDF (1169K)
Analytical Reports
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Miyu NAKAJIMA, Akira KOTANI, Fumiyo KUSU, Hideki HAKAMATAArticle type: Analytical Reports
2015 Volume 64 Issue 8 Pages 631-635
Published: August 05, 2015
Released on J-STAGE: September 03, 2015
JOURNAL FREE ACCESSFor the voltammetric determination of acid values in fat and oils based on the reduction prepeak of 3,5-di-tert-butyl-1,2-benzoquinone (DBBQ), a newly electrolyte cocktail containing 9 mM DBBQ, 48 mM LiCl, and 1.2 mM palmitic acid in 1-butanol was prepared. Also, the electrochemical cell and the voltammetric conditions were optimized. Deoxygenation from the electrolyte cocktail was not required to measure a voltammogram of DBBQ because the reduction peak potential of DBBQ was more positive compared with that of oxygen. The voltammetric prepeak height of DBBQ caused by palmitic acid was found to be linearly related to the palmitic acid concentrations in standard solutions from 0.042 mM to 2.5 mM (r = 0.999). This result showed that the determination of the acid values in fats and oils can be carried out by the present method, ranging from 0.031 mg to 1.85 mg. The analytical result of the acid value in olive oil by the present method was 0.212 mg using the standard addition method, while that by the official titration method of the Japan Agricultural Standards was 0.214 mg. Additionally, the acid values in commercial sesame, corn, grape seed, safflower, salad, and cottonseed oils determined by the present method also agreed with those by the titration method (r = 0.999). In terms of facility, environment-friendliness, and economy, the present method has advantages and thus would be applicable to a sensor to examine the deterioration of fats and oils in routine work.View full abstractDownload PDF (639K) -
Daichi SAWAMURA, Chisato KATO, Mayumi MATSUZAKI, Kazuya YANASE, Yoko T ...Article type: Analytical Reports
2015 Volume 64 Issue 8 Pages 637-642
Published: August 05, 2015
Released on J-STAGE: September 03, 2015
JOURNAL FREE ACCESSGlass products, such as glass beads excavated in Japan from Yayoi to Kofun period sites, were all produced abroad and brought to Japan via unknown ports. This paper reports on the results of non-invasive chemical analysis using a portable XRF on 253 glass beads excavated from various archaeological sites in the Kanto region. The base glasses were classified into three types: i.e., potash glass, soda lime glass, high alumina soda lime glass, which showed similar characteristics to those excavated from the Kyushu region. These similarities were also confirmed through trace element signatures of heavy elements. In the late Yayoi period, in both the Kyushu and Kanto regions potash glass comprised the majority of the glass chemical compositon; however, during the Kofun period, this changed to mainly soda lime glass in the Kanto region, while high alumina soda lime glass is dominant in the Kyushu region.View full abstractDownload PDF (867K)
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