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Chemical Mapping (chemical + mapping)
Selected AbstractsQuantitative Chemical Mapping of Relevant Trace Elements at Biomaterials/Biological Media Interfaces by Ion Beam MethodsADVANCED ENGINEERING MATERIALS, Issue 7 2010Edouard Jallot The definition of biomaterial as proposed by the European Society for Biomaterials in 1986 puts forward the overall importance of the notion of contact between the biomaterial and biological medium (cell, tissue, fluid,,). The underlying concept of biocompatibility makes the interface between biomaterial and biological medium a privileged zone of interest. In this paper, we would like to give an exhaustive view of how ion beams techniques can contribute to a better understanding of such interface taking several examples dealing with bone tissue substitution. After a short presentation of ion beams techniques the paper will focus on PIXE/RBS spectroscopies and will give the basics of these coupled technique. Three examples will then be presented to illustrate the interest of these techniques to study biomaterials/biological interactions. The first example deals with metallic alloys based joint prostheses. The ionic release from the prosthesis and the wear behavior of total knee prostheses will be presented. In the last two examples, bioactive materials will be studied. The common characteristic of bioactive ceramics is the kinetic modification of their surface upon interaction which is ideally monitored by PIXE chemical mapping. The second example will review the benefit of using PIXE/RBS technique to study the effect of doping of bioactive glasses on the very first steps involved in the bioactivity mechanisms like dissolution, ionic release, and biomineralization onto the surface of the glasses. Finally, protein delivery systems based upon mesoporous hydroxyapatites will be studied. Chemical mapping allowing the quantitative determination of protein distribution inside the HAp grains will be presented for the first time. [source] The Colours of MoleculesIMAGING & MICROSCOPY (ELECTRONIC), Issue 1 2006Chemical Force Microscopy Enables a New Look on Surfaces Abstract As the surface functionality is gaining more and more relevance in modern surface technology, the need for an analytical tool with chemical sensitivity and high lateral resolution is becoming important more than ever. In this article, we introduce the novel method "Chemical Force Microscopy" (CFM), which is enabling the chemical mapping of the surface with nm-resolution for the first time. This method has proved to be efficient to optimise and understand different processes on industrial surfaces. In the fields like plasma, coating, cell biology, pharmaceutical and printing technologies, this method has shown to be supremely efficient. [source] Analysis of video images from a gas,liquid transfer experiment: a comparison of PCA and PARAFAC for multivariate image analysisJOURNAL OF CHEMOMETRICS, Issue 7 2003Stephen P. Gurden Abstract The use of chemical imaging is a developing area which has potential benefits for chemical systems where spatial distribution is important. Examples include processes in which homogeneity is critical, such as polymerizations, pharmaceutical powder blending and surface catalysis, and dynamic processes such as the study of diffusion rates or the transport of environmental pollutants. Whilst single images can be used to determine chemical distribution patterns at a given point in time, dynamic processes can be studied using a sequence of images measured at regular time intervals, i.e. a movie. Multivariate modeling of image data can help to provide insight into the important chemical factors present. However, many issues of how best to apply these models remain unclear, especially when the data arrays involved have four or five different dimensions (height, width, wavelength, time, experiment number, etc.). In this paper we describe the analysis of video images recorded during an experiment to investigate the uptake of CO2 across a free air,water interface. The use of PCA and PARAFAC for the analysis of both single images and movies is described and some differences and similarities are highlighted. Some other image transformation techniques, such as chemical mapping and histograms, are found to be useful both for pretreatment of the raw data and for dimensionality reduction of the data arrays prior to further modeling. Copyright © 2003 John Wiley & Sons, Ltd. [source] Three-dimensional chemical mapping by scanning transmission X-ray spectromicroscopyJOURNAL OF SYNCHROTRON RADIATION, Issue 5 2007Göran A. Johansson Three-dimensional (3-d) chemical mapping using angle-scan tomography in a scanning transmission X-ray microscope is demonstrated. Apparatus, experimental procedures and data processing are presented and the 3-d spatial resolution is evaluated. The technique is illustrated using mapping of a low-density acrylate polyelectrolyte in and outside of polystyrene microspheres dispersed in water in a 4,µm-diameter microcapillary. The 3-d chemical visualization provides information about the microstructure that had not previously been observed. [source] Energy-dispersive absorption spectroscopy for hard-X-ray micro-XAS applicationsJOURNAL OF SYNCHROTRON RADIATION, Issue 5 2006S. Pascarelli Originally developed for time-resolved X-ray absorption spectroscopy (XAS), energy-dispersive absorption spectroscopy offers new opportunities for applications such as fluorescence detection and microbeams for scanning probe spectroscopy, thanks to recent developments in both instrumentation and optics. In this context, this paper presents a first example of chemical mapping recorded at ID24, the energy-dispersive XAS beamline at the ESRF. Attributes of this geometry for microanalysis are addressed. Finally, present and future plans are discussed and developed in the light of the evolution of the focal spot on this instrument in the past ten years. [source] | ||||||||||