The uptake of carcinogenic and mutagenic Cr compounds and the intracellular distribution of their biotransformation products in V79 Chinese hamster lung cells were studied by synchrotron-radiation-induced X-ray emission (SRIXE). SRIXE analysis was performed on whole cells that had been treated with either Cr(III) or Cr(V) 1,10-phenanthroline complexes, or Cr(VI). The high spatial resolution (0.3 microm) and elemental sensitivity (~10(-15) g Cr/cell) of the technique provided detailed maps of Cr and other cellular elements in thin sections prepared from Cr(VI)-treated cells. The Cr carcinogen concentrated in P-rich regions corresponding to the nucleus, as well as other areas of the cell that are likely to correspond to organelles. This is the first study that has enabled the determination of the localization of the biotransformation products of Cr(VI) carcinogens in a target lung cell.

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Abstract. A hard x-ray scanning microprobe based on zone plate optics and undulator radiation, in the energy region from 6 to 20 keV, has reached a focal spot size (FWHM) of 0.15 pm (v) x 0.6 pm (h), and a photon flux of 4x109 photons/sec/O.01 %BW. Using a slit 44 meters upstream to create a vitial source, a circular beam spot of 0.15 pm in diameter can be obtained with a photon flux of one order of magnitude less. During fluorescence mapping of trace elements in a single human ovarian cell, the microprobe exhibited an imaging sensitivity for Pt (La line) of 80 attograms/pm2 for a count rate of 10 counts per second. The x-ray microprobe has been used to map crystallographic strain and multiquantum well thickness in micro-optoelectronic devices produced with the selective area growth technique.The recent availability of high-brilliance synchrotrons radiation sources' and x-ray Fresnel zone plate microfocusing optics with high spatial resolution and high focusing efficiency has made possible the creation of a new tool for material characterization on micron and submicron length scales. A hard x-ray microprobe (HXRM) that combines microfocusing capabilities with x-ray sensitivity to trace element distributions, crystallographic strain, and the ability to penetrate deep in a specimen, has been developed for high-resolution fluorescence mapping and microdiffraction at the Advanced Photon Source (APS) at Argonne National Laboratory.The HXRM utilizes the radiation from the high-brilliance source generated from an electron beam of 7 GeV in the APS storage ring and a 3.3-cm-period undulator (&?S undulator A). The energy of the radiation can be tuned from 3.2 to 45 keV by a combination of varying the undulator gap and selecting among the f~st, third, and fifth harmonics of the undulator. The undulator has been optimized so that continuity in brilliance is achieved when tuning from one harmonic energy to the next.The HXRM is installed in a dedicated beamline (2-ID-D) specifically designed and developed for x-ray microscopic applications. The beamline was specially designed to achieve conservation of the source brilliance, selectivity of energy bandwidth, and the capability of reducing the effective source size. The beamline uses a windowless operation between the front end and the bearnline to avoid degradation 0[ wavefront due -. .. .

Abstract. Beam sizes of the stored electron beam at the Advanced Photon Source storage ring were measured using zoneplate optics and undulator radiation. A gold Fresnel zone plate (3.5 pm thick) located 33.9 meters from the x-ray source focused radiation of 18 keV, selected by a cryogenically cooled Si(ll1) crystal in horizontal deflection, and formed a source image in a transverse plane 2.41 m downstream. The sizes of the source image were determined from measured intensity profiles of x-ray fluorescence from a smooth nickel edge (1.5 pm thick), fabricated using a lithographic technique, while the nickel edge was scanned across over the beam in the transverse plane. The measured vertical and horizontal sizes of the electron beam were 60k4.3 pm and 3W-13 pm, respectively, in reasonable agreement with the expected values.

ABSTIMCTAn x-ray zone plate was fabricated using the novel approach of focused ion beam (FIB) milling. The FIB technique was developed in recent years, it has been successfully used for transmission electron microscopy (TEM) sample preparation, lithographic mask repair, and failure analysis of semiconductor devices. During FIB milling, material is removed by the physical sputtering action of ion bombardment. The sputter yield is high enough to remove a substantial amount of material, therefore FIB can perform a direct patterning with submicron accuracy. We succeeded in fabricating an x-ray phase zone plate using the Micrion 9500HT FIB station, which has a 50 kV Ga+ column. Circular Fresnel zones were milled in a 1.Opm-thick TaSiN film deposited on a silicon wafer. The outermost zone width of the zone plate is 170 nm at a radius of 60 pm. An achieved aspect ratio was 6:1.