Automated online preconcentration system for the determination of trace amounts of lead using Pb-selective resin and inductively coupled plasma-atomic emission spectrometry

An automated sequential-injection online preconcentration system was developed for the determination of lead by inductively coupled plasma - atomic emission spectrometry (ICP-AES). The preconcentration of lead was performed with a minicolumn containing a lead-selective resin, Analig Pb-01, which was installed between a selection and a switching valve. In an acidic condition ( pH 1), lead could be adsorbed on the resin. The concentrated lead was afterward eluted with 25 mu L of 0.06 M nitrilotriacetic acid (NTA) solution ( pH 9) and was subsequently transported into the nebulizer of ICP-AES for quantification. The selectivity of the resin toward lead was examined using a solution containing a mixture of 61 elements. When a sample volume of 5 mL was used, the quantitative collection of lead ( &#62;= 97%) was achieved, along with an enrichment factor of 19, a sampling frequency of 12 samples hr(-1), a detection limit of 70 pg mL(-1), and a lowest quantification limit of 100 pg mL(-1). The linear dynamic range was 0.1 to 5 ng mL(-1), and the relative standard deviation (n = 9) was 0.5% at a 5 ng mL(-1) Pb level. The detection limit of 30 pg mL(-1) and lowest quantification limit of 50 pg mL(-1) could be achieved when 10 mL of sample volume was used. The accuracy of the proposed method was validated by determining lead in the standard reference material of river water (SLRS-4), and its applicability to the determination of lead in environmental river water samples was demonstrated.</p

XMM-Newton Observation of IC 310 in the Outer Region of the Perseus Cluster of Galaxies

We present results from an XMM-Newton observation of the head-tail radio galaxy IC 310 located in the southwest region of the Perseus cluster. The spectrum is well-fitted by an absorbed power-law model with a photon index of $2.50 \pm 0.02$ with no significant absorption excess. The X-ray image shows a point-like emission at IC 310 without any signs of a structure correlated with the radio halo tail. The temperature of the intracluster medium surrounding IC 310 declines as a function of distance from the cluster center, from $kT \sim 6$ keV in the northeast corner of the field of view to about 3 keV in the southwest region. Although we do not find any sharp edges in the surface brightness profile, a brightness excess over a smooth $\beta$ model by about 20% is seen. The temperature also rises by about 10% in the same region. This indicates that the IC 310 region is a subcluster probably infalling into the Perseus cluster, and the gas in front of IC 310 towards the Perseus cluster is likely to be compressed by the large-scale motion, which supports the view that the IC 310 system is undergoing a merger.Comment: 7 pages, 8 figures (including color), accepted for publication in PAS

Chandra observation of the core of the galaxy cluster AWM7

We present results from a Chandra observation of the core region of the nearby X-ray bright galaxy cluster AWM7. There are blob-like substructures, which are seen in the energy band 2--10 keV, within 10 kpc (20'') of the cD galaxy NGC1129, and the brightest sub-peak has a spatial extent more than 4 kpc. We also notice that the central soft X-ray peak is slightly offset from the optical center by 1 kpc. These structures have no correlated features in optical, infrared, or radio band. Energy spectrum of the hard sub-peak indicates a temperature higher than 3 keV with a metallicity less than 0.3 solar, or a power-law spectrum with photon index 1.2. A hardness ratio map and a narrow Fe-K band image jointly indicate two Fe-rich blobs symmetrically located around the cD galaxy, with the direction perpendicular to the sub-peak direction. In larger scales (r<60 kpc), the temperature gradually drops from 4 keV to 2 keV toward the cluster center and the metal abundance rises steeply to a peak of 1.5 solar at r=7 kpc. These results indicate that a dynamical process is going on in the central region of AWM7, which probably creates heated gas blobs and drives metal injection.Comment: 12 pages, 7 figures (including color), accepted for publication in ApJ. Postscript is also available at http://www-x.phys.metro-u.ac.jp/~furusho/papers.htm

Chandra observation of the central galaxies in A1060 cluster of galaxies

Chandra observation of the central region of the A1060 cluster of galaxies resolved X-ray emission from two giant elliptical galaxies, NGC 3311 and NGC 3309. The emission from these galaxies consists of two components, namely the hot interstellar medium (ISM) and the low-mass X-ray binaries (LMXBs). We found the spatial extent of the ISM component was much smaller than that of stars for both galaxies, while the ratios of X-ray to optical blue-band luminosities were rather low but within the general scatter for elliptical galaxies. After subtracting the LMXB component, the ISM is shown to be in pressure balance with the intracluster medium of A1060 at the outer boundary of the ISM. These results imply that the hot gas supplied from stellar mass loss is confined by the external pressure of the intracluster medium, with the thermal conduction likely to be suppressed. The cD galaxy NGC 3311 does not exhibit the extended potential structure which is commonly seen in bright elliptical galaxies, and we discuss the possible evolution history of the very isothermal cluster A1060.Comment: 12 pages, 7 figures, Latex2e(emulateapj5), accepted in Ap