A specific XRF method, developed at the Soreq Nuclear Research Centre, was applied to the determination of bromine in blood. The method is based on excitation with a Mo X-ray tube and detection of the fluorescent Br K X-rays by a Si (Li) detector. Serum microsamples (300 μL) are counted directly, without drying, for 100 sec, The detection limit obtained under these conditions is 0.6 ppm Br, The overall precision of the method was found to be ±3.1%. The different parameters which contribute to the total error of the method were studied, A survey of the bromine concentration in the blood serum of industrial workers exposed to bromine compounds was carried out.

In order to determine the polluting atmospheric sources in urban and background areas source apportionment of the air particulate matter is necessary. Hitherto these studies were mostly based on bulk composition measurements of the aerosol. Source profiles, i.e. the concentrations of several elements for air particulate matter originating from one source, can be deduced from the receptor data using a number of multivariate techniques among which the chemical mass balance. The application is limited by the large number of observations that must be made for each of the variables. Often an elaborated sample preparation is necessary for fractionating the sample into several sub samples, according to the density, particle diameter or other relevant properties . Often this may results in poorly resolved source profiles.

Two sample preparation procedures for XRF determination of critical elements in process control samples of a lead smelter have been compared. The two methods, pressed powder(PP) and borate fusion(BF) were used in the analysis of (in order of importance) lead, zinc, copper, sulphur, arsenic and the flux elements (FeO, MnO, Al2O3, CaO, MgO and SiO2). The techniques were applied to three points in the overall lead-zinc-copper production process.

The three sample types have been selected to allow comparison between the BF and PP methods, where the PP method suffers from difficulties with particle size, moisture absorption or composition variation.

The BF technique was found to give better precision (typically 0.2 to 1% RSD) than the PP approach (typically 0.8 to 9% RSD), and to give better accuracy as found using reference materials. The stability of the BF bead over time is also of advantage in quality control. The flexibility and reliability of the BF technique has lead to its acceptance, and in part, to changes in the overall smelter analysis structure.

Chromium glycerate solutions are exposed to X-ray absorption fine structure analysis to clarify the local structure around the chromium atom by the use of a laboratory XAFS system. The chromium solution is stabilized by addition of water soluble polyvinyl alcohol so that after excess water, the solution is a kind of homogenized “sol” without any apparent charge to the solution state. The new technique has been developed, because chromium is an element which has relatively small X-Ray absorption.

The comformations of two novel chromium glycerate compounds, which are prepared under both NH4OH and NaOH basic conditions, are examined with XANES and EXAFS techniques. From these experiments, it is suggested that these two chromium glycerates may have Cr-O-Cr bridge bonds consisting of chromium dimer complexes in common.

In multielement EDXRF analysis of very complex unknowns, some problems in data evaluation may be simplified if one can take into account a priori information on the properties of the incident and detected radiations, and also available data on the matrix of the sample. The number of variables can be drastically shortened in the LSM procedures in this case. One of the best examples of complex unknowns is the determination of the rare earth element content of ores, and most recently in samples of high temperature superconductors (HiTc).

A new method, for the on-line determination of the composition and the coating weight of galvannealed (Zn-Fe-alloy-coated) steel sheets using monochromatic incident x-rays with two optical systems, is described. In the case of galvannealed steel sheets, it is difficult to determine the composition and the coating weight precisely by simple XRF, because fluorescent x-rays of Iron are emitted not only from the coating layer but also from the underlying steel sheets. We have developed an on-line analyzer with two optical systems which are different in incident angles, take-off angles and wavelengths of monochromatic incident x-rays. We determine the composition and the coating weight by solving simultaneous equations of the data which we derive using two optical systems. Using monochromatic x-rays enabled us to obtain high precision with high speed. We considered en-or factors in on-line measurement such as statistical error or fluctuation of the distance between the sensor head and steel sheets. This on-line analyzer has been applied to the continuous galvanizing line in our Fukuyama works successfully. As a result, we have been able to significantly improve product quality.

Three-dimensional tomographic reconstruction is capable of producing arrays of cubic voxels with resolution adequate to reveal important microstructural properties in materials. Visualization and measurement of these structures extends the types of information available from conventional 2D microscopy.

Scanning x-ray fluorescence microscopy is analogous to scanning electron microscopy. Maps of the distribution of chemical elements are produced by scanning the specimen with a very small x-ray beam while collecting the XRF spectrum. Our goal is to perform such scanning microscopy with resolution in the range of <1 to 10 μm, using standard laboratory x-ray tubes. In order to increase the radiation flux on the specimen, we are investigating mirror optics in the Kirkpatrick-Baez (K-B) configuration, K-B optics uses two curved mirrors mounted orthogonally along the optical axis. The first mirror provides vertical focus, the second mirror provides horizontal focus. We have used two types of mirrors: synthetic multilayers and crystals. Multilayer mirrors are used with lower energy radiation such as Cu Kμ. At higher energies such as Ag Kct, silicon wafers are used in order to increase the incidence angles and thereby the photon collection efficiency. In order to increase the surface area of multilayers which reflects x-rays at the Bragg angle, we have designed mirrors with the spacing between layers graded along the optic axis in order to compensate for the changing angle of incidence. Likewise, to achieve a large reflecting surface with silicon, the wafers are placed on a specially designed lever arm which is bent into a log spiral by applying force at one end. In this way, the same diffracting angle is maintained over the entire surface of the wafer, providing a large solid angle for photon collection.

Composition imaging of industrial samples has been reported using dual energy and multiple energy transmission computed tomography [1,2]. The simplest approach utilizes monoenergetic sources to obtain tomographs of a sample at two different energies. Each tomograph represents the linear attenuation coefficient distribution of the sample at the given source energy.

The physical basis for x-ray induced secondary electron emission in the range of the absorption edges is described. Applications of this principle for nondestructive composition determination and for nanometer resolved quantitative composition depth profiling are illustrated. A new commercial type of scientific instrument is presented which can be used for this new technique, and for almost all methods that require x-ray photon beam probing.

All the methods described in this paper are based on the same phenomenon, chat is, the phenomenon of the jump-like increase of x-ray photoabsorption in the vicinity of the x-ray absorption edges of the chemical elements of the sample.

Software has been developed for performing image reconstruction of analytical results from an X-ray microbeam spectrometer. The software system has been developed on a conventional IBM-AT compatible computer and runs under WINDOW 3,0 system. The interactive part is developed as a complete “window-style” program where the operator controls the sample movement, the MCA and the micrograph image from the microscope.

A description of the spectrometer and the software system is given. Applications of the technique in analysing documents are presented.

An X-ray Micro-Fluorescence (XRMF) spectrometer, with an analysis area of about 100 by 150 microns, has been used to collect 2-dimensional X-ray intensity maps over large-area (5 to 50 mm in X and Y) samples. These intensity maps were collected by scanning the sample on an XY stage, and converting X-ray Energy-Dispersive spectra to peak intensities for the elements of interest. The maps, when displayed using false-color or pseudogray scales, show the distribution of individual chemical elements over the analysis area. These maps can be collected at speeds from about 1 minute per frame (analysing 25 elements simultaneously). Greater precision of chemical intensities, or larger area maps, may require several hours, particularly if extensive data processing is performed at each point. XRMF has advantages over more conventional SEM-EDS X-ray mapping, including sample preparation and presentation, as well as improved signal-to-noise ratios.

A technique is described which assists in analyzing the large amount of data which is collected in each map. Principal Component Analysis (PCA) is performed on all of the elemental maps simultaneously. This technique compresses the many elemental intensity maps into a few principal components, resulting in many fewer maps to evaluate. The intensity maps of these principal components display the most pertinent information. They can also be plotted as scatter plots which can help with the partitioning of the data into individual phases. This procedure can potentially be automated as a method for phase analysis. The selected pixels from the scatter plots can be averaged and converted into phase compositions, and the phase information re-displayed on the original elemental or principal component maps.

This technique has been applied to a thin section of rock, and to a synthetic multiphase alloy sample.

A considerable number of the elements and a profusion of organic compounds are emitted into the atmosphere in association with solid and liquid particles. More than 50 percent of all air pollutants are preferentially present in particulate matter rather than in the gas phase. The assessment of the potential environmental and toxic effects of particulate matter in the atmosphere requires a detailed physical and chemical characterization. Methods for analyzing aerosols have recently been extensively reviewed by Maenhaut.

A new type of scanning X-ray diffracto-microscope (SXDM) / X-ray powder diffractometer (XPD) which uses a converged incident beam, was designed, manufactured, and some of its basic characteristics were examined. The optical system consists of asymmetric reflection type curved crystal monochromators for both incident and reflection beams, a detector (FSPC, X-ray film, IP, nuclear plate), a translation mechanism for the specimen and also for the detector.

We developed an X-ray fluorescence element mapping spectrometer (XEMS) based on commercially available energy dispersive XRF equipment several years ago. Using XEMS, we found that this technique is applicable to realtime observation of the elemental distributions in living biological samples. This kind of observation is almost impossible by conventional techniques such as EPMA, PIXE etc. But the spatial resolution of the previous system was about 200pm, Inferior by almost two orders to that of EPMA for example. So we developed a new spectrometer with an improved resolution of better than 20um and almost the same sensitivity.

A scanning X-ray analytical microscope was constructed using X-ray guide tube(XGT). XGT is a glass capillary which guides and focuses x-rays by total external reflection at the inner wall. The nature of X-ray beam passed through XGT is varied depending on the form of XGT. The cylindrical and conical types were used for the present setup. A small area (10μm × 10μm) of the sample was irradiated by the X-ray microbeam formed by XGT. Fluorescent and diffracted X-rays from the small area were detected by SSD. By scanning the sample in the plane normal to the X-ray microbeam, the intensity distributions of such secondary x-rays were measured and used as picture elements for constructing x-ray mapping images. The sample was a thin-section of an old chinaware. The images suggest a wide application of this instrument.

The success of new electronic materials has been due in part to the development of procedures that produce semiconductors of sufficient purity and perfection. These materials have been grown from the gas phase, solution, and melts. The Bridgman technique is one way semiconductor crystals are grown from the melt. In such furnaces the semiconductor material is usually sealed in an ampoule made of quartz or other suitable material, placed inside the tubular furnace, and heated to completely melt the sample. The ampoule with the molten material is slowly removed from the furnace by one of three ways.

An apparatus based on X-ray microfluorescence has been developed at IRSID in order to routinely and quantitatively determine the state of segregation in steels. The equipment consists principally of an iron anticathode X-Ray tube, a Si(Li) energy - dispersive detector and a “on the fly” operation in a multi-scale analysis mode. The acquisition of a chromium or manganese mapping in a (150 × 150 mm2) steel sample is possible over a total time of about one hour. The calibration curves for chromium or manganese are linear for the usual compositions of steels between 0.3% to 3%.

Synchrotron Radiation Induced X-ray Fluorescence analysis was successfully applied to the analyses of meteorites, archaeological objects and animal tissues. Electronic states of Fe and Ti in chondrules of chondrites were clarified by micro-XANES to be Fe2+ and Ti4+. Ancient iron implement (B.C. 3c A.D. 3c) with zoning of rusts was characterized by micro-XANES. Two dimensional chemical state analyses of the sample were made by selective excitation of iron. Trace element analyses of Cu, Zn, Se, and Hg in the brain and kidney of rat, mouse, and guinea pig dosed with alkyl mercury and/or Se were made from a view point of mercury intoxication. Strong correlation between Hg and Cu, Zn, Se was observed by the correlation analysis of the elemental distributions. The XRF imaging also disclosed decrease of Cu and Zn level in cancerous tissues of human kidney compared with normal ones.

Advantages of Synchrotron Radiation (SR) as an X-ray source of X-ray Fluorescence (XRF) Analysis have been demonstrated by many pioneering researchers. The advantages include wavelength tunability, high intensity and high resolution, which allow us to carry out nondestructive multielemental analysis of trace elements. However, practical application of the SR-XRF is still limited in numbers. The authors expected that the application of SR-XRF is most promising in the fields of archaeological objects, geological samples, and biological samples and started the present research projects in 1987. Now we have established the analytical procedures of these samples by SR-XRF that we report a part of our results, which so far we obtained from the analyses of geological samples, archaeological objects and biological samples.

The techniques of chemical state analysis used in this study are based on the following two approaches: one is XANES (X-ray absorption Near Edge Structure) and the other is SIXES (Selectively Induced X-ray Emission Spectroscopy). It is well known that the former technique together with EXAFS has been developed rapidly with the development of intense SR beams. SIXES was recently established by Sakurai et al. It enables us to carry out chemical state mapping by X-ray fluorescence using absorption edge shifts. This method was first applied to practical problems in this study.