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Microprobe instruments

Hitachi announced the development of the third commercial microprobe instrument, the ion microprobe analyzer IMA-2 in 1969 [30]. This instrument placed a scintillator close to the sample for secondary electron imaging. A Wien filter, for primary beam mass selection [31], and an electron spray, for charge compensation on insulating samples [32], were added later. [Pg.162]

Raman microscopy was developed in the 1970s. Delhaye (34) in 1975 made the first micro Raman measurement. Simultaneously, Rosasco (35, 36) designed a Raman microprobe instrument at the National Bureau of Standards (now the NIST). This early work established the utility of Raman spectroscopy for microanalysis. The technique provides the capability of obtaining analytical-quality Raman spectra with 1 pm spatial resolution using samples in the picogram range. Commercial instruments are available. [Pg.154]

In SR-scattering, a focus of 10 40 pm2 has been realized for a microprobe instrument, using two cylindrical mirrors (Kirkpatrick-Baez geometry [38]) as substrates. Such an optic appears to be suitable to reach focal spot sizes of 1 1 pm2 [39]. [Pg.223]

XPS analyses was performed on a Quantum 2000 Scanning SK Microprobe instrument. For the XPS analyses the samples were mounted on a sample plate, introduced into the XPS chamber and evacuated to <2x10 Pa. Elemental surveys and narrow scans were conducted with A1 KD X-rays on the uncalcined samples after which the temperature was increased to 573 K and 873 K (heating rate = 20 K min" ). Semi-quantitative data were calculated from the survey scans. The peak area ratios reported in this paper are fractions, which were calculated from the areas under the XPS peaks. The narrow scan data were used to determine probable compounds for the Co and C peaks. This was accomplished from a Gauss-Lorenzian peak fit of the appropriate photoelectron peaks. Wide spectra were recorded to obtain a semi-quantitative analyses of all elements present on the surface (except H and He) and high-resolution narrow spectra were recorded to identify the oxidation states and/or compounds. [Pg.49]

Measurements of the collagen samples were performed in a XPS microprobe instrument PHI Versaprobe (Physical Electronics, USA). The base pressure in the XPS analysis chamber was about 6x10 Pa. The samples were excited with X-rays over a 400 pm spot area with a monochromatic Al Kai 2 radiation at 1,486.6 eV. The photoelectrons were... [Pg.90]

Infrared Laser Desorption. Following the initial report by Kistemaker et al., Heresch et al. and Cotter combined pulsed IR laser desorption with sector instruments, while Vestal" and Stoll and Rollgen utilized quadrupole mass spectrometers to carry out laser desorption experiments. Further work by Kistemaker and co-workers established a thermal mechanism for laser desorption in which cat-ionized species were produced by gas-phase attachment of alakali ions to codesorbed neutral species. Cationized species were also observed at much shorter wavelengths (256 nm) by Heinen, while M-i-Ag+ ions were reported by Cooks et ah for solid samples deposited onto silver foils with ammonium chloride. The first laser desorption time-of-flight results were reported by Hercules and co-workers using a laser microprobe instrument to observe alkaU- and haUde-ion attachment in positive- and negative-ion mass spectra, respectively, and by VanBreemen et al." ... [Pg.125]


See other pages where Microprobe instruments is mentioned: [Pg.140]    [Pg.180]    [Pg.497]    [Pg.117]    [Pg.98]    [Pg.99]    [Pg.432]    [Pg.436]    [Pg.5183]    [Pg.18]    [Pg.139]    [Pg.15]    [Pg.108]    [Pg.262]    [Pg.24]    [Pg.354]    [Pg.262]    [Pg.346]   


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Microprobe

Microprobes

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