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This article concentrates on dynamic SIMS analysis using a magnetic sector instrument at micron and sub-micron resolutions with the ion microscope and ion microprobe modes. The advantages and drawbacks of both alternatives for recording measurements in laterally heterogeneous specimens are highlighted expecially concerning transmission and acquisition times. The ionization efficiencies and matrix...
Time-of-flight secondary ion mass spectrometry (TOF-SIMS) was used to study submonolayers of organic compounds of environmental significance adsorbed on coal flyash particles. Through the use of mass-resolved secondary ion images and mass spectra, chemical information on single particles was obtained. For example, TOF-SIMS was capable of distinguishing particles which had higher levels of adsorbed...
Static SIMS has shown itself to be a powerful tool for surface analysis with high chemical specificity. Because of the destructive nature of the sputtering process, high spatial resolution analysis (sub-200-nm regime) requires very high yields of emitted ions since there is a very limited amount of material in each image pixel. Generally the sputtered neutral yield is significantly greater than...
With the ion analyser IMS 4F used in microprobe mode, it is possible to obtain images of fields of 10 10 μm 2 , corresponding to an effective magnification of 7000 with lateral resolution of 250 nm, technical characteristics that are appropriate for the size of cell organelles. It is possible to characterize organelles by their relative CN - , P - and S - intensities...
The transport of K + , Na + , and Ca 2+ were imaged in individual cells with a Cameca IMS-3f ion microscope. Strict cryogenic frozen freeze-dry sample preparations were employed. Ion redistribution artifacts in conventional chemical preparations are discussed. Cryogenically prepared freeze-fractured freeze-dried cultured cells allowed the three-dimensional ion microscopic...
We present several techniques to reduce the matrix effect which hampers the quantification and the interpretation of SIMS analysis, particularly for the interface regions. We emphasise the MCs + technique (M, element to be analysed) which is one of the most useful and promising techniques. This technique is extended to MCs +2 which can be used to detect the electronegative elements...
Ultrasensitive SIMS with accelerator based spectrometers has recently begun to be applied to biomedical problems. Certain very long-lived radioisotopes of very low natural abundances can be used to trace metabolism at environmental dose levels ( z mol in mg samples). 14 C in particular can be employed to label a myriad of compounds. Competing technologies typically require super environmental...
A series of polyisobutylenes (PIBs) with average molecular weights from 800 to 4 10 5 were analyzed using time-of-flight secondary ion mass spectrometry (TOF-SIMS). The PIB spectra consist of a sequence of repeating patterns. Four clusters are observed within each pattern. Each cluster corresponds to several species, which are neutral fragments generated from polymer chain scission,...
Secondary ion mass spectrometry (SIMS) has been used for over 20 years by the microelectronics industry to determine in-depth distributions of dopants and impurities which become incorporated into semiconductor materials. SIMS not only has extremely high sensitivity (sub-part per million for almost all elements), but inherent in the secondary ion formation process is the ability to determine in-depth...
Time-of-flight correlation methods have been used to determine the primary structure of the major component in a nonstandard preparation of alamethicins, and to give some sequence information about minor components. The peptide (MW 2000 u) is blocked at the N terminus with an acetyl group and has a primary alcohol rather than a carboxyl group at the C terminus, so the usual wet chemical sequencing...
Secondary ion mass spectra and images were obtained from organic compounds deposited on gold and 30--50 μm thick biologic tissue substrates. Analyte solutions were prepared from acetylcholine chloride, choline chloride, and methylphenylpyridinium (MPP + ) iodide. Tandem mass spectrometry (MS/MS) was used to distinguish secondary ions characteristic of the analyte from secondary ions characteristic...
Recent instrumental developments of the conventional secondary neutral mass spectrometry (SNMS) technique based on electron gas post-ionization are described with regard to its application to non-conducting samples and its implementation in a novel secondary neutral microprobe. The use of molecular SNMS signals for quantitative surface analysis, and a standard free technique for absolute depth calibration...
Scanning ion microprobes, in conjunction with secondary ion mass spectrometry (SIMS) provide, at high spatial resolution, chemical, isotopic and morphological information about materials. A powerful analytical microscopy technique, scanning probe SIMS offers, in the best cases, 20 nm spatial resolution, with nanometer-scale depth resolution and parts per billion concentration sensitivity. By employing...
An accelerator mass spectrometer combines the electric and magnetic analyzing elements of a conventional mass spectrometer with a particle accelerator. Analyses are performed on ions with energies of the order of 10 million electronvolts (MeV) allowing the use of some techniques of nuclear physics to reduce or eliminate backgrounds from molecules and isobars. Sensitivities are achieved which allow...
The dynamic range, the erosion rate and the depth resolution achievable in small-area SIMS depth profiling has been studied using the quadrupole based ion microprobe ATOMIKA 4000. It was found that for a given object aperture of the oxygen or cesium ion gun the beam diameter is essentially independent of the beam energy (1.5-12 keV). Most of the results presented here relate to primary ion beams...
Hard-to-size bleached sulfite paper was examined by electron spectroscopy for chemical analysis, time-of-flight secondary ion mass spectrometry (TOF-SIMS) and ink penetration methodology. SIMS spectra indicated the presence of high mass fragment ions on the surface of the paper samples and SIMS images showed that these high mass peaks were present as aggregates as well as being dispersed on the paper...
The high energy particle bombardment of molecular films adsorbed upon a metal substrate has been investigated via molecular dynamics computer simulations with an empirical many-body potential function constructed for studying reactive dynamics. These calculations identify lateral motion of fragments in the overlayer as giving rise to fragmentation and direct abstraction type reactions. In addition,...
This paper takes you back almost half a century, to the time when mass spectrometry was young and exciting, and research was exploring new frontiers every day. Our early experiments called sputtering of surfaces by positive ion beams , now known as SIMS , were carried out with the simple, yet flexible instrumentation available at that time and produced many interesting results that are still...
Secondary ion mass spectrometry techniques for imaging measurements of 34 S 32 S isotope ratios and quantitative trace element concentrations in pyrite mineral grains have been demonstrated. Test samples show that the 34 S 32 isotope ratios are constant within Poisson error, independent of image position. Variable 34 S 32...
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