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[en] The effect of probe diameter upon secondary electron image contrast of periodic objects has been studied systematically. Interest in the topic arose following the observation of out-of-focus SEM images of conventional mesh support grids, where the basic periodicity was visible even with probe diameters many times the periodic spacing. The instrument used was a JEM-120CX/ASID operated in the SEM mode at low magnification with the objective lens off and other lenses in the free-control mode. The probe diameter at the specimen position was controlled by the continuously variable second condenser lens current. The first intermediate lens was focussed at the specimen position, thus allowing a determination of the probe diameter from the magnified shadow image, which could be photographed using the conventional TEM camera. The specimen used was a copper bar grid with spacings approx. = 125 μm
[en] The composition of the glazes of 14 fragments of medieval ceramics from Sistan in the south-west of Afghanistan has been determined quantitatively by means of electron probe microanalysis. The results were compared with materials and recipes, which are described in a Persian treatise on the manufacutre of glazed ceramic objects dated 1300 A.D. The mineral ''muzzarad'' which was used for the black underglaze painting, could be identified as chromite. The light blue colouring of the glaze was accomplished by admixtue of Cu, while Co was used for the dark blue painting. Most probably the Co pigment originated from Kashan in Persia. Only two glazes Pb was found, one of which contained also Sn. Based on the results of the quantitative analyses, a frit composition was calculated, which agrees with the medieval description of one identifies another so far unknown material mentioned in the treatise (qamsari) as dolomitic sandstone. (author)
[en] Complete text of publication follows. Production of metallurgical silicon with insignificant impurities is important for its application as the base material for solar elements. The samples of refined metallurgical silicon obtained by traditional technology contain some impurities, e.g. Fe 0.4, Al 0.3, Ca 0.4 wt. %. The goal of this study was to define the element and phase compositions of inclusions for developing the methods aimed at reducing abundances of impurities in silicon. The metallographic examination indicates presence of fine (from few microns to the tenth fractions of millimeters) metallic and nonmetallic inclusions in silicon samples. The Electron Probe X-ray Microanalysis (EPMA) provides information on the chemical and phase composition of fine inclusions. The investigation of metallurgical silicon samples by the electron microprobe (Superprobe-8200 with WDS and EDS) defined fine inter-metallic silicon-containing (silicides) and nonmetallic inclusions. The inter-metallic inclusions are small-sized (from 2 to 50 m) and occur on the boundaries between silicon grains. The data of quantitative analysis point out that silicides are composed of silicon 25-40 wt.%, aluminium 2-6 wt.% and iron 10-40wt.%. The chemical composition of inter-metallic silicon-containing inclusions is defined as adequate to the following phases in metallurgical silicon: Al5Fe2, (Fe,Ti)Si(Al), FeSi2(Al) and AlFeSi. Iron is bound with titanium, which can be replaced by manganese and vanadium. The nonmetallic oxygen-containing inclusions are round-shaped, their size reaches 300 m, and they consist of two or more phases. CaSiO3 and SiO2 are often present, while SiC inclusions occur infrequently. The data obtained agree with the results of x-ray phase analysis and metallographic investigations. They permit an appropriate scheme to be developed to use it in purifying refined metallurgical silicon. The further purification of metallurgical silicon was implemented by three methods. Initially, the multi-crystalline silicon was received by directed crystallization proceeding in vacuum 10-2 atm. and at temperature 1432 - 14520 C. In the second procedure the metallurgical silicon was refined without an oxidative flux, instead using the gas-air blend with high oxygen content, which accelerates production of admixed element oxides. In the third procedure consisted in refining silicon via adding quartzite as the flux with slow cooling of melt. Examination of the sample of metallurgical refined silicon after procedures of its purification by EPMA method shows, that multi-crystalline silicon by EPMA consists of pure silicon crystals with thin fibers of silicides lying on the boundaries between silicon grains. The sample, received in second procedures consists of pure silicon crystals containing composite metallic inclusions, on average sized from 1 to 10 m and silicon carbide 1-2 m, some inclusions reaching size 10 m. Of all the schemes tested the method of slow cooling of melt ensured the right approach to produce the most refined metallurgical silicon.
[en] Corophium valuator (Pal las) has been recommended by the Paris Commission as one of the standard species for testing chemicals used in offshore oil and gas exploration/production. In the present study, gut contents of corophium valuator have been analysed by electron probe microanalysis for BaSO4 and other heavy metal impurities after exposure to spiked sediments following a standard ASTM sediment bioassay protocol. Results show that depuration of corophium gut for 48 h in clean filtered seawater after exposure to sediments containing barytes, prior to whole body metal analysis, is required to reflect the true metal burdens
[en] The Hot Laboratory associated with the JMTR(Japan materials Testing Reactor, 50 MWt) was founded to examine the specimens irradiated mainly in the JMTR, and was put into service in 1971. PIE facilities at the beginning were 8 concrete cells, 4 microscope cells and 7 read cells, thereafter 5 steel cells, a shield type EPM(electron probe micro analyzer), a set of BOCA(BOiling water CApsule) assembling equipment and 4 glove boxes for PIEs of beryllium were added. A wide variety of PIEs has been carried out in the Hot Laboratory until now. Appropriate renewal was done for in cell apparatus, manipulators, power manipulators, shield window's glasses and so on, as these were worn out. In addition, currently a large restructuring of in cell apparatus is under was to accommodate user's new needs