Infrared (IR) absorption of molecules is enhanced , greatly (101-103 times) when they are adsorbed on or near vacuum-evaporated Ag or Au thin films. By using this surface Enhanced i$ absorption (SEIRA) phenomenon, we could obtained IR spectra of some organic molecules of a few picogram amount in good signal-to-noise ratios. Thus, the SEIRA spectroscopy is promising as a new trace analytical technique. General properties of SEIRA found in our experiments are summarized . An electromagnetic theory of this phenomenon is proposed. Key W surface enhanced infrared spectroscopy, trace analysisOptical properties of molecules are altered dramatically when they are adsorbed on or near some rough metal surfaces. Surface enhanced Raman scattering (SERS) [1] is the most prominent example. Similar surface enhanced

BACKGROUNDIt is known that chromium is an inhaled carcinogen and an important risk factor in the development of lung carcinoma.METHODSThe authors used a microscopic X‐ray fluorescence analyzer with transmitted X‐ray mapping imaging (Horiba, Kyoto, Japan) to measure the accumulation of chromium in 10 resected lung tissue specimens and 90 biopsy specimens from chromate workers.RESULTSThe maximum chromium accumulation (mean ± standard deviation) in 10 resected lung tissue specimens was 197 ± 238 counts per second (cps)/mili ampere (mA) (range, 4–649 cps/mA). Chromium accumulation was scattered in six tissue specimens and diffuse in one specimen. Chromium accumulation in the proximal bronchi was less than in the bronchioles or subpleural regions of the lung. Chromium accumulation was detectable in 63 (70%) of 90 biopsy specimens, and the mean accumulation was 6.5 ± 9.2 cps/mA (range, 0–46.5 cps/mA). Chromium detected in bronchial tissue specimens was deposited in the bronchial stroma but not in the epithelium. The maximum chromium accumulations in dysplasic (n = 3), squamous metaplastic (n = 10), and normal bronchial epithelia (n = 9) in chromate workers and in normal bronchial epithelia (n = 3) in non‐chromate workers were 20.2 ± 5.4, 18.3 ± 12.2, 13.2 ± 13.4, and 3.0 ± 1.8 cps/mA, respectively. The amount of chromium accumulation significantly increased according to the progression of malignant change of the bronchial epithelium (P = 0.003).CONCLUSIONSPrevious studies found that lung carcinoma with chromate exposure exhibited a variety of genetic abnormalities. Considering genetic aberrations and chromium accumulation in these premalignant lesions is useful for elucidating the process of carcinogenesis in chromium‐induced lung carcinoma. Cancer 2003. © 2003 American Cancer Society.

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We developed a transportable micro‐XRF (µ‐XRF) spectrometer using a polycapillary X‐ray focusing half lens, which was placed between the sample and the detector. The total weight of the developed spectrometer was about 2 kg; its dimensions were 18(W) × 26(D) × 40(H) cm. The spatial resolution of the spectrometer with the half lens of a working (focal) distance of 30 mm was 171 µm at Fe Kα, which was evaluated by a wire scanning method. In this setup, it is easy to replace the polycapillary X‐ray half lens with one having a different analytical performance, because a precise position‐adjustment of the X‐ray lens is not required. The spacial resolution with the half lens of a working distance of 16 mm was 106 µm at Fe Kα. Depending on analyzing area on the sample and required spatial resolution, we can easily change the X‐ray lens, as in a conventional optical microscope. The calibration curves of V, Cr, Mn, and Ni measured for standard steel materials showed good linear relationships (correlation coefficients >0.993). Clear elemental mapping could be obtained by scanning the sample (Cu mesh). An elemental analysis of a micro‐region in an electronic device was also performed by the transportable µ‐XRF spectrometer. Sn and Pb were detected at the metallic part (Sn–Pb solder) of the device. Br and Ba were observed at some resin parts of the electronic device. Copyright © 2009 John Wiley & Sons, Ltd.

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