No abstract available

[en] The results of scanning a finely collimated beam of 5.9 keV X-rays across the faces of three different Si(Li) X-ray detectors are interpreted in terms of an active area of good charge collection and peripheral regions of incomplete charge collection, both within the manufacturers' stated areas. The data are correlated with absolute efficiencies determined using calibrated radionuclide X-ray emitters. The hazards of spectral artefacts from the imperfect regions in the contexts of XRF and PIXE are stressed. (orig.)

[en] Semiconductor detector X-rays to obtain energy selective answers including a semiconductor block, possessing two lateral faces, the first face being covered by an electrode succession with elongated strip shape having various widths, these electrodes being put away in order of increasing widths, the weakest width electrode being next to the X-ray receptive fore face, the second side face being covered with at least one electrode. Application to inspection, checking, monitoring or object characterization. 5 refs., 5 figs

[en] Published in summary form only

[en] Pediatric foreign body (FB) ingestion is a common problem throughout the world. The type of FB that is ingested, the anatomical location of the FB, and the time to medical presentation are all factors that determine how the child will be treated. We present the different types of foreign bodies that are ingested as well as highlight the differences and similarities in their management plans. (author)

[en] Coded-Mask imaging systems may be considered as generalisations of the pinhole camera in which the 'coding-plane' contains a carefully chosen pattern of transparent and opaque regions, instead of a single pinhole. A variety of instruments results from selecting different coding patterns and from simple geometrical variations on this theme. The variois schemes which have been proposed and used and the methods of interpreting the data obtained with them are reviewed and compared. Emphasis is placed on systems for X-ray astronomy. (orig.)

[en] This invention concerns radiation detectors in general and, in particular, refers to a new solid state detector of X rays as well as arrays formed of such detectors. A large number of applications require the accurate measurement of radiation flux intensity. This is so in computer assisted tomography systems and, particularly, in tomography systems with a very high resolution for the non-destructive testing of mechanical components, since these tests require a very high degree of accuracy. Greater accuracy of measurements is also important in the more conventional systems of X ray imagery, in medical, industrial and other fields. In accordance with the invention, when making a radiation detector, a coat of photoconducting material, such as selenium, is used for it has the characteristic of possessing a variation in conductance between opposite edges of the coat when a variation in the incident radiation flux occurs. An electrode is formed on each of the surfaces presented by these opposite edges, the electrode material being selected to reduce to the minimum the obscurity current flowing in the detector when the photoconducting coat of this detector is polarized

[en] An analysis of internal damage increase was performed for samples of winter and spring wheat, for damage caused by dynamic loading. The internal damage increase was determined separately for every kernel, on the basis of its damage status before and after loading. The internal damage status (endosperm cracks) was assessed by means of a damage index calculated on the basis of results of damage identification within the fields of a square grid superimposed on the X-ray image of a kernel analysed. Increase in the mean damage index for a grain sample was adopted as a measure of the vulnerability of the grain sample to damage caused by the load applied. Quantitative and qualitative analyses were performed for the status of damage of the grain samples of the varieties under study. Especially interesting conclusions were formulated analysing the 'damage balance' of the grain samples. The methods used in the study can be applied also in other laboratory studies on damage to cereal grain or to the seeds of certain crop plants, e.g., when studying the effects of the successive stages of their destruction. (author). 3 refs, 6 figs, 1 tab

[en] X-ray method to determine internal damage of seed, mainly its endosperm, was used. A roentgenogram obtained by this method was analysed manually only (at present time). Number of cracks, size and location was assessed for each kernel of sample. Kernels of wheat, barley and malt were used. An algorithm for analysis of biological damage of barley was used. In this case the surface of kernels of barley was damage. For quantification of the internal damage of seeds it is very important to obtain the clear roentgenograms for next semi-automatic processing. Current works are undertaken to computerize the analysis of the roentgenograms. (author). 12 refs, 3 figs

[en] Among inorganic crystalline luminescent compounds, X-ray luminophors are distinguished by the facts that their conversion efficiency is most sensitive to their intrinsic and impurity structural defects and that the quality of the image obtained by them depends to the greatest extent on the particle form and the perfection of their surface. Screens with calcium tungstate luminophors having oval particles with a smooth surface remain unsurpassable in image quality. The efficiency of this luminophor is 5-6%, whereas that of yttrium oxosulfide activated by terbium is nearly 13%. However, it should be noted that the quality of an image is determined not only by the shape of the particles and their packing in the luminophor layer, which depends on the manner of its formation, but also on the luminophor efficiency. An imperfect layer yields structural graininess of an image, and small doses attained at high efficiency produce so-called quantum graininess of an image. Thus, quantum fluctuations limit the tendency toward higher efficiency. Luminophors with an efficiency of 10-12% and with particles similar to those of calcium tungstate luminophor appear to be optimal for most roentgenographic trends in medicine. It is natural that these are only the necessary conditions for producing the open-quotes idealclose quotes X-ray screen because the formation of a perfect luminophor layer from such a luminophor is a separate problem