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Mishima Y.,Tsurui Chemical Co. | Maruyama H.,Canon ANELVA Co. | Hino K.,Canon ANELVA Co. | Tsugoshi T.,Japan National Institute of Advanced Industrial Science and Technology | And 3 more authors.
Bunseki Kagaku | Year: 2011

In this study, a data-analysis technique for vegetable oil discrimination was discussed and offered using Ion Attachment Ionization (IA) Mass Spectrometry, which has a completely soft ionization technique with no fragmentation during ionization. In IA ionization mass spectra, only quasi-molecular ion peaks are obtained, so that the mass spectra showed the characteristic pattern, which reflected the states in the sample, even if there was no pre-separation technique, such as gas-chromatography. Referring to the database of soft-ionization mass spectra for nine kinds of vegetable oils, which was processed beforehand, oil discrimination and estimated values of mixed ratio were possible to be carried out with principal-component and cluster analyses, and a different calculation method of regression analysis, respectively. These methods should be useful for selective marking to the trace impurity in oils, e.g., 0.4 wt% signal of coconut oil in olive oil was detected. © 2011 The Japan Society for Analytical Chemistry.


Mitsui T.,Data Analysis Laboratory | Okuyama S.,Criminal Investigation Laboratory
Bunseki Kagaku | Year: 2011

The values of multiple correlation coefficients and coefficient determinations are obtained by multiple-regression analysis. The values of the multiple-correlation coefficient and coefficient determination show the extent of the variation in measured values. A known sample to more than 0.999 value of the multiple-correlation coefficient and coefficient determination was used for quantitative analysis. An inadequate unknown sample for accurate quantitative analysis was determined from the values of multiple correlation coefficients and coefficient determinations. When the multiple-correlation coefficient and coefficient determination were less than 0.99900, the unknown samples were un-suitable for the quantitative analytical results. At this time, the determinations of inadequate samples for accurate quantitative analysis using 13 measured values by GC-MS were performed by this method. © 2011 The Japan Society for Analytical Chemistry.


Okuyama S.,Criminal Investigation Laboratory | Kaneko E.,Tohoku University | Hida M.,Criminal Investigation Laboratory | Mitsui T.,Data Analysis Laboratory
Bunseki Kagaku | Year: 2010

A visual spot test has been developed to make it possible to discriminate between different types of fine paper using Bromochlorophenol Blue (BCPB)-hydrochloric acid solutions. When a drop of the solution is dropped onto a piece of paper, the solution retains a semispherical shape or spreads through the capillaries depending on the water repellency of the paper, and depending the on paper composition, either a yellow or blue stain appears. When six BCPB solutions with different concentrations of hydrochloric acid in the range of 0.01 ~ 0.6 N were separately applied to eight kinds of paper, they were able to be classified into six groups according to differences in their water repellency and the color change of BCPB upon drying. Furthermore, the eight kinds of paper that had been printed using an inkjet printer were also able to be classified into five different groups, despite a loss of water repellency due to printing. There was good agreement between the color change of BCPB on the paper and the amount of calcium carbonate filler in the paper. Our visual method serves as a first-stage screening test for the discrimination of paper without any special equipment, and will be useful in practical forensic examinations. © 2010 The Japan Society for Analytical Chemistry.


The determination of carbon monoxide hemoglobin (CO-Hb%) in blood by different calculation methods involving regression analysis (DCR) and principal component score (PCA) was carried out using 0 %and 100 %of CO-Hb%in blood. However, both hemoglobin and carbon monoxide hemoglobin in blood are degenerated by heat or putrefaction. As a result, the correct CO-Hb% in blood is not obtained, and any judgment of the cause of death may be mistaken. Thus, the degree of degeneration of blood was examined based on regression statistics (R2), the sum of the coefficient in the multiple-regression equation, and the sum of the third principal component score. As a result of degenerations, the values of R2 and the sum of the coefficients in multiple regression equation decreased, and the sum of the third principal-component score is increased. Consequently, the presumption of the degree of degeneration in blood was attained from the change of these values. Also, a check of the cause of degeneration was attained from the third principal-component residual spectrum of the sample blood. Furthermore, the correct CO-Hb% in the sample blood was calculated from the determination value of CO-Hb% and the absorbance of the third principal component of 533 or 570 nm. © 2013 The Japan Society for Analytical Chemistry.

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