In the present study, by heating a quartz glass substrate having the dry residue of a 10 μL droplet of a solution of HAuCl and a counter substrate facing to the dry residue from room temperature to one hundred and several tens of degrees Celsius in 20 min in air, highly dense gold nanoparticles were produced on the counter substrate. A gold nanoparticle substrate produced by this simple method was utilized as a substrate for surface-enhanced Raman scattering analysis.
View Article and Find Full Text PDFIn this study, single synthetic fibers obtained from several textile products were analyzed by a portable total reflection X-ray fluorescence spectrometer. Characteristic elements, which would originate from such materials as catalysts, delustering agents, and dyes used for manufacturing synthetic fibers, were detected from single synthetic fiber samples, and the difference in the types of characteristic elements among the single synthetic fiber samples was observed.
View Article and Find Full Text PDFAn easy method is presented for producing gold nanoparticles. We show that by performing simultaneous low-temperature heating of a quartz glass substrate on which the dry residue of a 10 μL droplet of an HCl acidic solution of HAuCl·4HO is deposited and a counter substrate using Peltier devices in a low vacuum produced by a rotary pump, gold nanoparticles with sizes ranging from about twenty to one hundred and several tens of nanometers are produced on the counter substrate. In this study, an application of a gold nanoparticle substrate produced by this method to the sample holder for surface-enhanced Raman scattering analysis is also shown.
View Article and Find Full Text PDFThis paper describes a method for obtaining information that can contribute to individual identification from a single hair colored with a hair dye product using a combination of surface-enhanced Raman scattering (SERS) and X-ray fluorescence (XRF) analyses. SERS and XRF spectra of single hog hairs colored with several commercially available hair dye products were measured. SERS spectral patterns tended to be different depending on the hair dye products used for hair coloring.
View Article and Find Full Text PDFThis study describes a sample preparation method for trace element analysis using total reflection X-ray fluorescence analysis. The procedure of this method is as follows: 1) a hydrophobic-coated sample holder whose hydrophobic film at around the center of the surface is partially dissolved by acetone is prepared; 2) a droplet of a sample solution is dropped on the sample holder; and 3) the sample droplet is heated and dried while vibrating it. This sample preparation method is effective for reducing the size of the dry residue of the sample solution and suppressing the coffee-ring formation.
View Article and Find Full Text PDFA method is presented for the detection of a trace amount of cyanocobalamin (vitamin B) using a combination of solid-phase extraction and the measurement of cobalt in vitamin B by a portable total-reflection X-ray fluorescence spectrometer. Using this combination, a detection limit of 1 ng/mL was achieved for vitamin B.
View Article and Find Full Text PDFUsing a portable total-reflection X-ray fluorescence (TXRF) spectrometer with a collodion film sample holder, a spectrum of an analyte containing 50 ng of aluminum was measured. The Al Kα line (1.49 keV) that partially overlaps with the Si Kα line (1.
View Article and Find Full Text PDFTo improve the detection limits of a portable total reflection X-ray fluorescence (TXRF) spectrometer using white X-rays (i.e., both characteristic X-rays and continuum X-rays) from a 5 W X-ray tube, the measurement was performed in vacuum.
View Article and Find Full Text PDFA diamond-like carbon (DLC) coated quartz glass sample holder is used in a portable total reflection X-ray fluorescence (TXRF) spectrometer. A spot area of a water sample on the DLC sample holder becomes smaller than that on a quartz glass sample holder usually used in TXRF analysis because DLC is more hydrophobic. Therefore, the use of the DLC sample holder enhances fluorescent X-rays reaching a detector compared with the use of a quartz glass sample holder, leading to improvement in detection sensitivity.
View Article and Find Full Text PDFDetection limits obtained by a portable total reflection X-ray fluorescence (TXRF) spectrometer with or without a monochromator are compared. A 1 W X-ray tube (tube voltage: 20 kV) is used in this spectrometer. Polychromatic excitation improves the detection limits in TXRF analysis with the low power X-ray tube compared with monochromatic excitation.
View Article and Find Full Text PDFA portable instrument for two-dimensional X-ray fluorescence imaging was assembled with an X-ray source using a pyroelectric crystal, which was driven by a 9-V dry battery, a Si-PIN detector, a slit, and pulse motors. Line scanning for a mug and a knife-edge-scan of an iron sheet were carried out using this spectrometer. The sensitivity of the spectrometer was sufficient for elemental analysis of a mug using a 1 mm(2) slit, and several elements, such as Co, Ni, Zn, Pb and Zr, were detected.
View Article and Find Full Text PDFA portable total reflection X-ray fluorescence spectrometer was applied to commercial bottled drinking water containing 62 ppb (microg/L) V, 7.5 ppm (mg/L) Ca, and 1 ppm K. A dry residue, prepared by repeated pipetting and drying a 20 microL portion of drinking water on a sample holder six times, and another dry residue, prepared by pipetting and drying a 120 microL portion of the drinking water, were measured.
View Article and Find Full Text PDFA portable total reflection X-ray fluorescence spectrometer is presented. The present spectrometer mainly consists of a 1.5-W X-ray tube, a waveguide type slit, a detector, and a sample carrier (a quartz optical flat), and these components are contained in an attache case-type box.
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