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[en] We discuss the results of SEM and TEM measurements with the BPRML test samples fabricated from a BPRML (WSi2/Si with fundamental layer thickness of 3 nm) with a Dual Beam FIB (focused ion beam)/SEM technique. In particular, we demonstrate that significant information about the metrological reliability of the TEM measurements can be extracted even when the fundamental frequency of the BPRML sample is smaller than the Nyquist frequency of the measurements. The measurements demonstrate a number of problems related to the interpretation of the SEM and TEM data. Note that similar BPRML test samples can be used to characterize x-ray microscopes. Corresponding work with x-ray microscopes is in progress.
[en] An electron biprism for a 1 million-volt field-emission electron microscope was developed. This biprism is controlled similarly as a specimen holder so that it can be driven and rotated precisely and is tough against mechanical vibration and stray magnetic field. We recorded the maximum number of interference fringes by using this biprism in order to confirm the overall performance as a holography electron microscope, and obtained a world record of 11,000 interference fringes
[en] ln this research, two kinds of sands were used as a sample, i.e. Cilacap sand and Aceh sand. The sand was milled until the grain was fine, and then it was pressed so that 20 mm diameter of pellet was resulted. The pressure was about 7 tons. The sample of pellet then to be sintered at 1100oC during 2 hours. The sintered pellet was polished gradually using SiC paper, then using diamond paste 6μm and I μlm, and then it was etched using Nital solution. The result of analysis using optical microscope and SEM/ WDX was indicated that mineral contents of Cilacap sand and Aceh sand were almost the same, i.e. mineral of magnetite, hematite, ilmenite, marcasite. chalcopyrite. cuprite. uvarovite and TiO2 compound. Despite the fact that SiO2 compound was only identified in Aceh sand
[en] The asymmetrical magnetic electron lens is of great importance for the electron microscopes intended for high resolution. Such lenses are determined not only by its geometric structure and shape parameters but also by the gap width to bore diameter (S/D) of its pole pieces. a systematic investigation has been carried out for asymmetric objective lenses having different bore diameters. The results indicate that the op per h ore diameter of pole piece lens has considerable effects on the electron optical properties. The Comparison between the two sets of the family of asymmetric lenses provides good performance, and suggests that the ratio of the lens gap width to the bore diameters of its pole pieces (S/ D<1) is obtained. and the limits of the upper bore diameters to the lower ones which equals (D1/D2=3) are favourable. (authors). 9 refs., 9 figs
[en] Verification of the reliability of metrology data from high quality x-ray optics requires that adequate methods for test and calibration of the instruments be developed. For such verification for optical surface profilometers in the spatial frequency domain, a modulation transfer function (MTF) calibration method based on binary pseudo-random (BPR) gratings and arrays has been suggested (Proc. SPIE 7077-7 (2007), Opt. Eng. 47(7), 073602-1-5 (2008)) and proven to be an effective calibration method for a number of interferometric microscopes, a phase shifting Fizeau interferometer, and a scatterometer (Nucl. Instr. and Meth. A 616, 172-82 (2010)). Here we describe the details of development of binary pseudo-random multilayer (BPRML) test samples suitable for characterization of scanning (SEM) and transmission (TEM) electron microscopes. We discuss the results of TEM measurements with the BPRML test samples fabricated from a WiSi2/Si multilayer coating with pseudo randomly distributed layers. In particular, we demonstrate that significant information about the metrological reliability of the TEM measurements can be extracted even when the fundamental frequency of the BPRML sample is smaller than the Nyquist frequency of the measurements. The measurements demonstrate a number of problems related to the interpretation of the SEM and TEM data. Note that similar BPRML test samples can be used to characterize x-ray microscopes. Corresponding work with x-ray microscopes is in progress.
[en] A method for fabrication of mechanical elements (microturbines) that receive torque from vortex optical beams is proposed. Experimental results on fabrication of multiple microturbines are presented. Shapes of the microturbines are measured using an optical microscope, ZYGO white-light interferometer, and electron microscope.
[en] Ceramic brackets were introduced to overcome the esthetic disadvantages of stainless steel brackets. The clinical impression of these brackets is very favorable. However, the sliding mechanics used in the Straightwire (A Company, San Diego, CA, USA) system appear to produce slower tooth movements with ceramic compared to stainless steel brackets. To determine whether this was due to any obvious mechanical problem in the bracket slot, Transcend (Unitek Corporation/3M, Monrovia, CA, USA) ceramic brackets were examined by a scanning electron microscope and compared to stainless steel brackets.Consistently, large surface defects were found in the ceramic bracket slots that were not present in the metal bracket slots. These irregularities could obviously hinder the sliding mechanics of the bracket slot-archwire system and create a greater demand on anchorage. Conversely, the fitting surface of the Transcend ceramic bracket showed extremely smooth surface characteristics, and it would seem advisable for the manufacturers to incorporate this surface within the bracket slot. (author)
[en] The observational results in optical and electronic microscopy of the magnetostatic microorganisms (Chlamydomona and coccus) found in the Rio de Janeiro waters, Brazil, are presented. (L.C.)
[pt]Apresentam-se os resultados observacionais em microscopia otica e eletronica dos microorganismos magnetostaticos (Chlamydomona e coccus) encontrados nas aguas do Rio de Janeiro, Brasil. (L.C.)