bluuebunny/crossref_metadata_2025_split huggingface dataset:
New growth features of natural diamonds, revealed by color cathodoluminescence scanning electron microscope (CCL SEM) technique
Authors: Zezin R. B. , Smirnova E. P. , Saparin G. V. , Obyden S. K. 
Published: August 2011

AbstractThe internal structure of diamonds with various habit was studied by color cathodoluminescence scanning electron microscopy (CCL SEM). A new growth mechanism was ascertained for diamonds of rounded and octahedral habit. The specific growth details found by means of CCL SEM testify to the fact that the crystallization of diamonds proceeded from the specimen periphery toward the centre by formation of agate secretions. CCL determined was the structure of transparent cubic crystals to be a combination of zones with cuboid surfaces and fibrous structure. The authors consider that both cuboid and fibrous structures are the result of normal (nontangential) growth mechanisms which may be realized during secretional filling of the space, determined for a number of crystals of rounded and octahedral habitus.
Reactive ion etching of GaAs with SiCl4: A residual damage and electrical investigation
Authors: Cole M. W. , Salimian S. , Cooper C. B. , Lee H. S. , Dutta M. 
Published: August 2011

AbstractThe residual damage incurred by various SiCl4 reactive ion etching (RIE) conditions was investigated by transmission electron microscopy (TEM), Raman spectroscopy, ion channeling, and electrical characterization methods. Lattice damage to depths greater than 100 nm was incurred in all of the RIE processing situations. The lowest power density, longest etch time RIE exhibited the lowest defect density, roughest surface morphology, and poorest quality GaAs regrowth. The highest power density, shortest etch time RIE displayed the highest defect density, smoothest surface morphology, and highest quality GaAs regrowth. The electrical measurements, Schottky diode characteristics, degraded with decreasing power density and increasing etch times. Overall, the characterization results suggest that the high power density, shortest etch time sample possesses the most desirable properties for device fabrication requirements.
Quantitative x‐ray microanalysis of spherical inclusions embedded in a matrix using a SEM and Monte Carlo simulations
Authors: Gauvin Raynald , L'Espérance Gilles , St‐Laurent Sylvain 
Published: August 2011

AbstractThe current schemes of quantification of x‐ray microanalysis in the SEM [ZAF and σ(ρZ) methods] are valid for specimens of homogeneous composition. The determination of the chemical composition of small inclusions using these techniques is impossible because the volume of x‐ray emission is not of homogeneous composition. A scheme of quantification to determine the composition of small inclusions embedded in a matrix has been developed using Monte Carlo simulations. This scheme is similar to that developed by Kyser and Murata (1974) for the quantification of thin foils deposited on a substrate using x‐ray microanalysis in the SEM.
In situ topography measurement in the SEM
Authors: Thong J. T. L. , Breton B. C. 
Published: August 2011

AbstractAn automatic technique for measuring heights in situ in the SEM based on a combination of stereo‐metric and focusing methods has been developed. A pair of images of a surface element on the specimen is obtained by tilting the beam electrically in a manner such that the plane containing the tilt axis is coincident with the focal plane of the final lens. Cross‐correlation is used to determine the parallax between the image pair which is then used to iteratively correct the height of the tilt axis by changing the lens focus. As a result, the lens focus tracks the specimen topography. With an appropriate specimen surface containing high resolution features for image correlation, the technique is capable of maintaining both its lateral and vertical resolutions over several decades of height displacement up to 100 μm. In an experimental system based on a commercial electron‐optical column, spot, line profile, and three‐dimensional measurements have been demonstrated.
Optimized reflection imaging in laser confocal microscopy and its application to neurobiology: Modificationsa to the biorad MRC‐500
Authors: Szarowski D. H. , Smith K. L. , Herchenroder A. , Matuszek G. , Swann J. W. , Turner J. N. 
Published: August 2011

AbstractReflection images of biological specimens recorded using laser‐scanned confocal microscopes are frequently degraded by low image contrast, poor signal to noise, and the inability to image deeper in the specimen than 10–20 μm. Artifactual internal reflections often are a source of these limitations, but they can be reduced or eliminated by the use of polarization components. Designs for the incorporation and optimum use of these components in the BioRad MRC‐500 are presented. The effect of the internal reflections was reduced by optimum rotational alignment of both a quarterwave plate and an analyzer. Absorption of incident and reflected light by both the stained cells and the background tissue of the specimen also seriously degrades image signal to noise, and is a function of specimen preparation and the wavelength of light used. The red line of a helium‐neon laser was not as readily absorbed as the blue and green lines of an argon‐ion laser when imaging neurobiological specimens contrasted with either peroxidase/diaminobenzidine or Golgi staining. Specimens many times thicker were imaged with red laser light and with superior image quality compared with blue or green laser light.
An efficient single crystal BSE detector in SEM
Authors: Autrata R. , Hermann R. , Müller M. 
Published: August 2011

AbstractUsing the optical modifications described, the signal of the wide‐angle BSE detector can be increased 3.7‐fold compared with the detector type illustrated in Figure 1. The increase was achieved by more fully exploiting the optical phenomena of diffusion, reflection at the critical angle and antireflection, and especially that of their combined effects. A higher photon energy transfer was obtained by specific optical modifications to the scintillator and the light guide. Based on the current modifications, it can be estimated that about 75% of the generated light reaches the PMT. It is necessary, therefore, to revise all values previously published of the DQE coefficient of the YAG scintillator. A general value of DQE is of very limited use depending as it does on the specific conditions under which light emerges from the YAG scintillator. The DQE, therefore, does not permit sufficiently accurate comparison with other scintillation materials. The DQE can be evaluated only for a completed detector configuration in which the laws of geometrical optics apply, or it can be used for making comparisons of scintillation materials used in the same detector configuration.
Chromatism and confocality in confocal microscopes
Authors: Akinyemi O. , Boyde A. , Browne M. A. , Hadravsky M. , Petran M. 
Published: August 2011

AbstractIn confocal microscopes, whenever a broadband light source is used, or when excitation and detection are performed at different wavelengths, for example in fluorescence, then the influence of microscope objective chromatism on the degree of confocality is very important. With poorly corrected objectives, depth of field will be increased and in the case of fluorescence the image may be lost altogether. Presented here are observations with truly achromatic reflecting objectives and with the same objectives modified by introduction of a known amount of chromatic aberration. The results should encourage manufacturers to consider development and production of both reflecting microscope objectives and refractive lenses with more carefully designed/controlled chromatic aberration.
Fluorescence lifetime imaging using a confocal laser scanning microscope
Authors: Buurman E. P. , Sanders R. , Draaijer A. , Gerritsen H. C. , van Veen J. J. F. , Houpt P. M. , Levine Y. K. 
Published: August 2011

AbstractThe implementation of a fast fluorescence life‐time imaging method in a confocal laser scanning microscope is described. The set up utilizes a low‐power continuous wave (CW) argon ion laser equipped with an electro‐optic chopper producing nanosecond pulses with a repetition rate up to 25 MHz. A time‐gated detection technique enables the measurement of the lifetime of a pixel in 40 μs. The first confocal fluorescence lifetime contrast images are presented. Application of fluorescence lifetime imaging in multilabelling experiments for discrimination between different labels with overlapping emission bands, for probing the local environment of a fluorescent molecule, and for quantitative fluorescence are discussed.
Microsecond duration pressure pulse generator for in situ dynamically loaded SEM fracture studies
Authors: Fishbine B. H. , Macy R. J. 
Published: August 2011

AbstractWe describe a technique to impulse load small cylindrical specimens for in situ, real‐time SEM studies of dynamically loaded fracture. Loading is done magnetically with a solenoidal coil of 10 mm length and 1 mm radius. The entire loading assembly fits on the SEM stage; there is no need for shock‐isolated bellows apparatus. The only vacuum feedthrough required is an MHV coaxial bulkhead connection. A ballistic pendulum measurement gave a peak compressive pressure of ∼20 MPa, with a pressure pulse width of 1.33 μs. Pressures > 80 MPa can easily be generated. Using this device we have obtained real‐time SEM movies of dynamically loaded fracture of rosin.
Acquisition and processing of scanning electron microscope images using a PC and a framestore
Authors: McClean J. A. , Dhariwal R. S. , Milne N. G. 
Published: August 2011

AbstractA versatile, low‐cost data acquisition and processing system for scanning electron microscope (SEM) images has been successfully developed and demonstrated. This is based on an Amstrad PC and a framestore interfaced to the SEM, and is an upgrade of an earlier BBC microbased system. In addition to supporting colour x‐ray mapping, as reported previously, the PC‐based unit incorporates new features which enhance the system's performance, flexibility, and overall user friendliness. An example of the system's capabilities in a very large‐scale integrated circuit application is presented. This relates to the processing and analysis of a series of images taken on the surface of a Motorola MC 68000 microprocessor, with and without a voltage stimulus.
Point spread function of the general cone‐beam x‐ray reconstruction formula
Authors: Wang G. , Lin T. H. , Cheng P. C. , Shinozaki D. M. 
Published: August 2011

AbstractIn this paper, the spatially varying point spread function (PSF) of the general cone‐beam x‐ray reconstruction formula is derived. It is proved that the vertical integral of the PSF is a two‐dimensional δ function. Therefore, although the general cone‐beam formula is not exact in nature, the vertical integral of the reconstructed three‐dimensional image is equal to that of the actual image. The band‐limited version of the PSF is also derived. The PSF of the general cone‐beam formula is simulated, based on which the reconstruction resolution can be approximately inferred.
Space heterogeneity of luminescent centers in SiC‐epitaxial layers detected by the color CL‐SEM
Authors: Saparin G. V. , Mokhov E. N. , Obyden S. K. , Chukichev M. V. , Roenkov A. D. , Ivanov A. I. 
Published: August 2011

AbstractThe spatial distribution of luminescence centers in SiC epitaxial layers grown by the sublimation “sandwich method” have been studied by means of the real‐colour SEM technique. The cellular inhomogeneity distribution of cathodoluminescence (CL) intensity in epitaxial layers is demonstrated. Different spectral composition of CL emission depending upon the growth temperature is observed near p‐n junctions and along the substrate boundary. The nature of the inhomogeneities in SiC epitaxial layers is discussed.
Identification and study of the same cell in monolayer culture by different methods of light microscopy, scanning, and transmission electron microscopy. Application for cryodamaged cells examination
Authors: Katsen A. D. , Tregubova N. A. , Andrushkevich V. V. , Rovensky Yu. A. 
Published: August 2011

AbstractCells were cultivated on transparent conductive substrates, glass slides coated with indium oxide; individual cells were marked with a diamond indentor. Cell cultures were frozen (–15°C), thawed, and then stained with fluorescent dyes to determine cell damage. The marked cells were examined by phase contrast, fluorescence, and Nomarski DIC microscopy. After aldehyde and osmium tetroxide fixation, the cell preparations were sequentially treated with tannic acid, uranyl acetate, and lead citrate. The same marked cell could be sequentially studied by light microscopy (LM; in water immersion conditions), scanning electron microscopy (SEM; after dehydration and critical point drying), and transmission electron microscopy (TEM; after embedding of cell samples in epoxy resin and laser marking of the cell previously marked with a diamond indentor). The method used ensures good preservation of cell morphology, cell surface relief, and intracellular structures. The treatment used renders the cells conductive and permitted SEM of uncoated culture cells on conductive substrates.
Cryoscanning electron microscopy of microbial extracellular polysaccharides and their association with minerals
Authors: Chenu C. , Jaunet A. M. 
Published: August 2011

AbstractThe morphology of pure microbial extracellular polysaccharides (EPS) and of their association with a mineral was studied by scanning electron microscopy. Several methods were compared: cryo‐SEM, critical point dehydration (CPD), and TEM observation after solvent exchanges and inclusion in a resin. The EPS were observed as fibrils, interconnected into a network. Their dimensions were compared with literature data on the conformation and shape of the given EPS. It was deduced that these EPS have an undoubtably fibrillar structure when hydrated, and that some aggregation or collapse artifacts took place in both CPD or cryo‐SEM samples but were quite limited. Cryo‐SEM appears then as a relevant tool for the study of the secretion of EPS by microorganisms in soils.
Deconvolution of scanning electron microscopy images
Authors: Yano Fumiko , Nomura Setsuo 
Published: August 2011

AbstractThis paper describes a method of removing blurs in scanning electron microscopy (SEM) images caused by the existence of a finite beam size. Although the resolution of electron microscopy images has been dramatically improved by the use of high‐brightness electron guns and low‐aberration electron lenses, it is still limited by lens aberration and electron diffraction. Both are inevitable in practical electron optics. Therefore, a further reduction in resolution by improving SEM hardware seems difficult. In order to overcome this difficulty, computer deconvolution has been proposed for SEM images. In the present work, the SEM image is deconvoluted using the electron beam profile estimated from beam optics calculation. The results show that the resolution of the deconvoluted image is improved to one half of the resolution of the original SEM image.
Comparison of ion beam sputtered chromium and iridium films for electron microscopy applications
Authors: Cardinale G. F. , Carlino V. L. , Howitt D. G. 
Published: August 2011

AbstractThe structure and composition of thin, conductive metallic films of chromium and iridium that are typical of the coatings used for electron microscopy is described. The purpose of this study was to determine the grain size and composition of the films deposited, with thicknesses of 1 nm, 2.5 nm, and 5 nm, onto amorphous carbon films using ion beam sputtering with argon as the sputtering gas. A comparison between chromium films deposited under conditions of liquid nitrogen (LN) trapping or of no trapping revealed slight differences in their microstructure. As expected, the grain size of the films increased with the thickness, and the average grain sizes varied between 10 and 25 nm. Grain size was also found to depend on the source of ion beam energy; the correlation between grain size and beam energy was more pronounced in the iridium films than in the chromium films. This effect was greater when the deposition chamber was not LN trapped. As the ion beam energy increased from 18 W to 24 W, there was a corresponding increase in grain size in some of the films. Although transmission electron diffraction analysis indicated the presence of about 5% chromium oxide in the chromium films, no oxide was detected in the iridium films.
Possibilities of modulated cathodoluminescence for multilayer structure characterization
Authors: Kireev V. A. , Razgonov I. I. , Yakimov E. B. 
Published: August 2011

AbstractThe basic principles of modulated cathodoluminescence (MCL) are discussed herein, and the possibilities of the technique are demonstrated, using computer simulation of the MCL signal in a framework of simplified assumptions. Extension of the dependences obtained for less specific cases are discussed. The procedures for separation of the CL spectra associated with the different layers of two‐ and three‐layer structures are also described.
Low‐temperature scanning electron microscopy in fungus‐nematode interaction
Authors: Den Belder E. , Boekestein A. , Van Esch J. W. J. , Thiel F. 
Published: August 2011

AbstractA comparative study has been made of different preparation techniques used for the scanning electron microscope (SEM), with regard to their application to fungus‐nematode interaction. The preparation of frozen‐hydrated specimens of both healthy and Arthrobotrys‐oli‐gospora‐infected second‐stage larvae of the root‐knot nematode (Meloidogyne sp.) is described, and the results are compared with those obtained by critical point‐drying and freeze‐drying. In all cases the frozen‐hydrated specimens consistently showed the best preservation.
Video‐rate confocal reflection microscopy of neoplastic cells: Rate of intracellular movement and peripheral motility characteristic of neoplastic cell line (RSK4) with high degree of growth independence in vitro
Authors: Vesely P. , Jones S. J. , Boyde A. 
Published: August 2011

AbstractVideo‐rate laser confocal interference reflection microscopy was used to demonstrate rapid motion of intracellular organelles and features at the cell periphery in a fully transformed neoplastic cell line, RSK4, and in four other neoplastic cell populations. In the RSK4 cells, vibrational and trafficking movements of intracellular particles at a rate greater than 25 Hz and ranging down to 5 Hz were recorded. Rapidly moving processes changed to ruffles, then microspikes, and previously undetectable ephemeral intercellular contacts were seen. Dynamic cyclical changes were revealed in the sizes of the podosomal close contacts of the transformed cells. The visibility of such features and the temporal and spatial resolution are improved over earlier methods. The fact that fast cellular and intracellular movements can be detected with this microscopic technique offers new possibilities in attempting to recognise differences between unimpaired living cells, and it may prove useful in the identification of malignant cells.
Imaging and colour coding of magnetic domains by kerr scanning optical microscopy
Authors: Büscher P. , Reimer L. 
Published: August 2011

AbstractThe imaging of ferromagnetic domains by the transverse Kerr effect using a scanning optical microscope (SOM) with two or four directions of light incidence (± x, ± y) allows the digital record of the By and Bx components of the magnetic induction B. These components can be used to calculate a two‐dimensional colour‐coded map of B, which can be superposed by vector arrows.
Application of confocal laser scanning microscopy to analysis of H2O2‐induced DNA damage in human cells
Authors: Fairbairn Daryl , O'Neill Kim L. , Standing Michael D. 
Published: August 2011

AbstractConfocal laser scanning microscopy (CLSM) offers improved depth discrimination and spatial resolution to the analysis of biologic samples. We demonstrate in this paper that such technology is valuable in examining DNA single‐strand breaks in human cells. The single‐cell‐gel (SCG) assay is a new technique for measuring DNA strand breaks in individual cells. Cells embedded in lowmelting‐point agarose are treated with varying concentrations of hydrogen peroxide to induce DNA strand breaks. Following cell lysis and alkaline electrophoresis, which enables single‐stranded break detection, analysis of the resulting “comets” provides an accurate method of comparing changes in DNA migration patterns, which have been shown to reflect the DNA damage levels. A statistically significant difference (p < 0.01) in single‐stranded DNA damage levels was detected in cells exposed to hydrogen peroxide concentrations as low as 10 nm for 2 min. LSM analysis of the SCG technique allows rapid, sensitive and reproducible quantitation of single‐stranded breaks of cellular DNA.
A formula to compute total elastic mott cross‐sections
Authors: Gauvin Raynald , Drouin Dominique 
Published: August 2011

AbstractA formula to compute total elastic Mott cross‐sections as well as a tabulation of the constants to compute total Mott cross‐sections for 94 elements are presented herein. This formula and the constants have been obtained from the values of total elastic Mott cross‐sections computed by Czyżewski et al. (1990) using Thomas‐Fermi‐Dirac atomic potentials for atomic numbers greater than 54 and Hartree‐fock potentials for atomic numbers less than 55. Also, a Monte Carlo program simulating the trajectories of electrons in bulk specimens using our formula of total elastic Mott cross‐sections and the single scattering approach is discussed. Values of backscattering coefficients in energy functions for C, Al, Cu, Ag, and Au computed by this program and by other Monte Carlo programs are compared with values measured experimentally by several researchers.
Low‐temperature SEM studies of beam‐induced voltage contrast in YBCO thin films
Authors: Hollin C. A. , Hall Y G. , Hulbert J. K. , Zarucki P. N. , Sutton S. D. , Abell J. S. 
Published: August 2011

AbstractBeam‐induced voltage contrast has been demonstrated in a superconducting thin film of YBa2Cu3O7‐x (YBCO) grown on MgO. Copper‐rich inclusions in the material contribute to spatially varying resistive behaviour but do not account for all the observed details. A new method of scanning in which the beam was moved away from the sample between each data acquisition point was found to increase the resolution by limiting thermalisation, to allow imaging of resistive features as small as 0.5 μm. Direct comparisons of beam‐induced contrast and micro‐structure at 9000 times magnification were possible using simultaneous image acquisition via a purpose‐built image store. Mounting a preamplifier within the scanning electron microscope chamber, to give a variable overall gain of 1000–100,000, was also found to significantly improve the signal‐to‐noise ratio.