Showing papers on "Transmission electron microscopy published in 1981"
Journal Article•
TL;DR: The preparation, labelling, stabilization, stability and binding characteristics of gold markers are reviewed, and several problems related to steric hindrance and quantification of the method are also discussed.
Abstract: Gold sols are orange to violet, display electron dense properties and are capable of strong emission of secondary electrons. These properties enable gold particles to be used as specific markers in microscopy both at the low and high resolution level (light and fluorescent microscopy, scanning and transmission electron microscopy). Monodisperse colloidal gold can be produced by several methods in a size range of 5 nm to 150 nm. As a consequence, the gold method is well suited for multiple marking experiment at the high resolution level. Since gold markers bind non-specifically to a very low extent, the technique has found application in TEM for marking intracellular components on thin sections. Both the one step and the two step marking procedures have been utilized in the various modes of microscopy. Under appropriate conditions, gold particles can be labelled with a variety of macromolecules (polysaccharides, glycoproteins, proteins, lectins, antibodies), presumably through a noncovalent binding process. Generally the probes acquire the specific activity of the adsorbed macromolecule and their stability upon storage is good. A number of factors which influence the adsorption process are discussed in relation to the more general problems of adsorption of macromolecules onto metallic surfaces. The stability of gold markers is also best understood by the DLVO theory for disperse systems. The preparation, labelling, stabilization, stability and binding characteristics of gold markers are reviewed. Since the binding of gold probes to cell surfaces is primarily determined by the size of the particle, several problems related to steric hindrance and quantification of the method are also discussed. The advantages of the method over others are compared. The different modes of microscopy and the several gold methods available for marking cell surface and intracellular components are illustrated by micrographs.
227 citations
TL;DR: In this article, the magnetic grains isolated from magnetococcoid bacterial cells were studied by means of transmission electron microscopy, electron diffraction and electron microprobe analysis, which supported the contention that the magnetic bacterial grains are single-domain crystals capable of producing a natural remanent magnetization in sediments.
172 citations
TL;DR: In this paper, the surface structure of (111) gold platelets was studied by ultra-high vacuum transmission electron microscopy and diffraction and the results were described in this series of papers.
109 citations
TL;DR: In this paper, a pyrolytic hydrogen reduction of MoO2Cl2 in the temperature range 550-710°C on both quartz and metal substrates is described.
95 citations
TL;DR: In this article, it was concluded that the fairly high bond strength of a Al2O3-Nb interface might be attributed to the formation of a thin NbOx layer, which had grown epitaxially on the surface.
Abstract: Diffusion couples of Al2O3 single-crystal, sapphire, and Nb polycrystal were heat-treated in the temperature range 1873 to 2073 K under pressure in the range 3 to 15.2 MN m−2 for various times up to 3.6×103 sec. Tensile testing at various temperatures up to 1873 K in a vacuum of about 10−3 Pa, Knoop hardness testing at room temperature, optical microscopy, scanning electron microscopy, transmission electron microscopy, and electron-probe X-ray microanalysis studies were carried out on the specimens. From the results, it was concluded that the fairly high bond strength of a Al2O3-Nb interface might be attributed to the formation of a thin NbOx layer, which had grown epitaxially on the Al2O3 surface. Lattice matching between Al2O3 and NbOx phases was also considered.
91 citations
TL;DR: In this paper, the ion-induced amorphous Au-Si alloy is uniform in composition and in thickness as indicated by 4He+ backscattering measurement, and two distinct stages of phase transformation are observed as revealed by a sudden change of resistivity with increasing annealing temperature.
Abstract: An amorphous Au-Si alloy with composition Au-28·5 at. % Si (Au5Si2) has been formed by inplanting energetic Xe, Ar or Ne ions through a thin layer of Au deposited on a Si substrate. The ion-induced amorphous Au-Si alloy is uniform in composition and in thickness as indicated by 4He+ backscattering measurement. The Au-Si alloys so obtained were studied by resistivity measurements and by transmission electron microscopy and diffraction. Two distinct stages of phase transformation are observed as revealed by a sudden change of resistivity with increasing annealing temperature. In the first stage, a transformation from amorphous to a metastable crystalline Au5Si2 phase occurs in a narrow temperature range around 100°C. The second stage, which appears broader near 180°C, involves the transformation to the equilibrium two-phase state of Au and Si. The kinetics of the amorphous to metastable crystalline transformation has been determined by isothermal annealing over the temperature interval 85-101°C. An...
84 citations
TL;DR: In this article, the authors used electron diffraciton and transmission electron microscopy to study the domains and domain walls of lead zirconate titanate and showed that the 90° and 180° domains are deformation twins with displacement along 〈110〉 on {110}.
Abstract: The crystallography of the domains and domain walls in lead zirconate titanate are studied using electron diffraciton and transmission electron microscopy. Both 90 ° and 180 ° domains are observed and the 90° domains are shown to be deformation twins with displacement along 〈110〉 on {110}. The thickness of the 90 ° domain wall is determined to be ≲100 A.
72 citations
TL;DR: In this paper, the authors show that the NiSi2 (111) surface has a bulklike periodicity parallel to the surface, whereas the (100) surface exhibits reconstruction periodicity.
Abstract: Epitaxial NiSi2 films have been grown on (100) and (111) Si. Interface and surface structures have been examined by Rutherford backscattering and channeling, transmission electron microscopy, and low‐energy electron diffraction. The (111) interface is remarkably flat, whereas the (100) interface has {111} facets. The NiSi2 (111) surface has a bulklike periodicity parallel to the surface, whereas the (100) surface exhibits reconstruction periodicity.
71 citations
TL;DR: Micrographs of uncoated glass substrate surfaces obtained by replicating films used for transmission electron microscopy as well as investigations by SEM and electron micro-probe techniques indicated that particular surface defects or contaminations of submicroscopic size act as the nuclei necessary for the formation of nodules.
Abstract: The investigation of nodular defects in both thick dielectric single layers and multilayer systems by scanning electron microscopy (SEM) reveals the nodules to be of essentially the same shape no matter how many layers were deposited and what materials were used. The SEM micrographs of a thick LaF3 layer used in IR coatings and of TiO2/SiO2 multilayer systems are presented. Whereas the nodules in the thick fluoride layer are clearly caused by small spherical particles in an underlying layer of Ge, the cause is less obvious with the multilayer nodules. However, micrographs of uncoated glass substrate surfaces obtained by replicating films used for transmission electron microscopy as well as investigations by SEM and electron microprobe techniques indicated that particular surface defects or contaminations of submicroscopic size act as the nuclei necessary for the formation of nodules. A growth model and possible measures to prevent nodular defects are discussed from a general point of view.
67 citations
TL;DR: The elemental composition of the non-crystalline intergranular phase in two MgO-fluxed hot-pressed silicon nitrides, determined by X-ray microanalysis and electron energy loss spectroscopy in the transmission electron microscope, is reported in this article.
Abstract: The elemental composition of the noncrystalline intergranular phase in two MgO-fluxed hot-pressed silicon nitrides, determined by X-ray microanalysis and electron energy loss spectroscopy in the transmission electron microscope, is reported. The composition is similar in both and lies near the SiO2-MgSiO3 tie line with impurities of Ca, Al, and Cl. No nitrogen could be detected in the noncrystalline phase, implying that the nitrogen concentration was below the experimental detectability limit.
66 citations
TL;DR: In this paper, the formation conditions of single crystalline silicide films on Si substrates by solid phase reactions were investigated using MeV He+ Rutherford backscattering and channeling techniques and transmission electron microscopy.
Abstract: Formation conditions of single crystalline silicide films on Si substrates by solid phase reactions were investigated using MeV He+ Rutherford backscattering and channeling techniques and transmission electron microscopy It was shown that single crystalline silicide films (NiSi2, CoSi2 and Pd2Si) can be formed on (111)Si when metals are deposited onto clean surfaces and they are annealed without exposure to air Channeling minimum yields in the backscattering analysis were 003–004 in NiSi2 and CoSi2 films thinner than 150 nm and 006 in Pd2Si films thinner than 100 nm In the transmission electron microscopy measurement, grain boundaries were not observed at least in an area of 100×100 µm2, but several defects like twins and dislocations were observed in some silicide films The resistivity of silicide films was also measured by the four-point probe method, and the resistivities of CoSi2, Pd2Si and NiSi2 were about 15 µΩ-cm, 25 µΩ-cm and 35 µΩ-cm, respectively
TL;DR: Two methods of specimen preparation for the scanning electron microscope (SEM) have been combined for the reliable exposure and examination of nervous system tissue and the enhanced mass-density of myelin resulting from the amplification of osmium's natural affinity for unsaturated lipids was best demonstrated by the backscatter electron mode of the SEM.
Abstract: Two methods of specimen preparation for the scanning electron microscope (SEM) have been combined for the reliable exposure and examination of nervous system tissue. When the specimen is postfixed with OsO4 prior to aqueous cryofracturing, large internal surfaces of nervous tissue are exposed, with minimal distortion to the cytoarchitecture. All tissue surfaces and interstices are subsequently impregnated with a conductive, metallic layer of osmium using a modified osmium-thiocarbohydrazide-osmium technique (OTOTO). This OTOTO technique permits SEM examination without any additional vacuum evaporated or ion-sputtered metallic layers, and has been found to eliminate specimen charging reliably. Nervous tissue has been examined in the secondary electron mode of the SEM with unrestricted use of beam currents varying from 1.3 to 60 μA, at accelerating voltages ranging from 2.5 to 80 kV, and at both low (10 ×) and high (80 000 ×) magnifications. In addition, a differential deposition of osmium in the tissue after the OTOTO technique has been identified using both transmission electron microscopy and energy dispersive X-ray microanalysis. The enhanced mass-density of myelin resulting from the amplification of osmium's natural affinity for unsaturated lipids was best demonstrated by the backscatter electron mode of the SEM. This mode of imaging was found useful in the identification of myelin sheaths.
TL;DR: The results of ultra-high-vacuum transmission electron microscopy on the condensation process of a few monatomic layers of lead on silver surfaces were reported in this paper.
TL;DR: In this paper, the laser-induced oxidation of amorphous silicon has been investigated and the oxide layer formed by this rapid melting and resolidification process has been observed when the irradiation takes place in an O2 or in an air ambient.
Abstract: Amorphous silicon has been produced on a single‐crystal silicon surface that was exposed to intense pulsed UV‐laser radiation at 266 nm. In addition, the formation of an oxide several tens of nanometers in thickness is observed when the irradiation takes place in an O2 or in an air ambient. Various experimental techniques including transmission electron microscopy, sputtered Auger electron spectroscopy, and differential Fourier‐transform IR spectroscopy have been employed to characterize the laser‐induced amorphous silicon and the oxide layer formed by this rapid melting and resolidification process. The present study suggests a new oxidation phenomena, namely, ’’laser‐induced oxidation.’’
TL;DR: In this article, the metallic glass layers were produced on metallic bulk material using laser or electron beam melting using X-ray, scanning electron microscopy, transmission electron microscope, and calorimetric methods.
Abstract: Metallic-glass layers were produced on metallic bulk material using laser or electron beam melting. The requisite composition (FeCr12)80(C,B)20 for steel and NixNb(100−x), (x = 30 to 60) for niobium was obtained by coating the substrate prior to melting. X-ray, scanning electron microscopy, transmission electron microscopy and calorimetric methods were used to demonstrate and investigate the amorphous nature of the surface layer.
TL;DR: In this article, transmission electron microscopy of ultramicrotomed sections of anodic barrier-type films formed on aluminum in tungstate solution reveals directly the duplex nature of the anodic films.
TL;DR: In this paper, the microstructures of oxide scales on SiC single crystals, produced by oxidation at 1400°C for various lengths of time, were studied by light and transmission electron microscopy and by X-ray diffraction.
Abstract: Microstructures of oxide scales on SiC single crystals, produced by oxidation at 1400° C for various lengths of time, were studied by light and transmission electron microscopy and by X-ray diffraction. At short oxidation times the oxide films were amorphous; at longer times they consisted of spherulitic cristobalite. The cristobalite is thought to grow by devitrification of the amorphous phase. No significant difference in oxide scale thickness or structures was found between commercial purity and semiconductor grade crystals.
TL;DR: In this paper, the thermal decomposition of molecules containing boron and nitrogen gives coatings with a composition close to BN and chemically inert towards halogens and halides.
Abstract: The thermal decomposition of molecules containing boron and nitrogen gives coatings with a composition close to BN and chemically inert towards halogens and halides. The decomposition at 900–950 °C of the cyclic hexachloroborazine (approximate formula B 3 N 3 Cl 6 ) was studied. The coatings were characterized using X-ray diffraction, mass and IR spectroscopy, scanning electron microscopy, transmission electron microscopy, secondary ion mass spectrometry and electron microprobe analysis (energydispersive X-ray analysis). The use of coated silica tubes for chemical vapour transport of TiB 2 was examined.
TL;DR: Magnetic susceptibility, electrical resistivity, Mossbauer effect (ME) and transmission electron microscopy measurements in single crystals of the metal intercalated layer compounds FexTaS2 (0.20⩽x ⩽0.34) are reported in this article.
Abstract: Magnetic susceptibility, electrical resistivity, Mossbauer effect (ME) and transmission electron microscopy measurements in single crystals of the metal intercalated layer compounds FexTaS2 (0.20⩽x⩽0.34) are reported. The compounds are metallic, ferromagnetic and have large coercive force. ME measurements show the iron to be high‐spin Fe2+, with a distribution of hyperfine fields at low temperatures. Transmission electron microscopy suggests the existence of clusters. These results may explain the diversity of magnetic preperties on nonstoichiometric intercalated compounds such as FexTaS2.
TL;DR: In this paper, the authors used an ordinary transmission electron microscopy technique to observe atomic steps on the surfaces of silicon single crystal and showed that the steps were formed during heat treatment of the crystal at 1200°C in the ultra-high vacuum system.
TL;DR: Improved image quality in soft x-ray contact microscopy can be obtained by examining the resist with transmission rather than scanning electron microscopy, and platelet pseudopods contain a central structure connected to a network in the platelet and dense bodies exhibit a lamellar structure.
Abstract: Improved image quality in soft x-ray contact microscopy can be obtained by examining the resist with transmission rather than scanning electron microscopy. Application of the new technique to air-dried preparations of human blood platelets reveals structures not visible in the same cells with transmission electron microscopy or when the resist is examined by scanning electron microscopy. As seen by the new technique, platelet pseudopods contain a central structure connected to a network in the platelet and dense bodies exhibit a lamellar structure.
TL;DR: In this paper, the electrical conductivity of discontinuous metal films in weak fields is investigated using a special chamber in a transmission electron microscope with a device for electron interference, and the results obtained allow us to evaluate critically the current theories and to show the important role of the charge effect in the conductivity.
TL;DR: In this paper, the structure of an Fe83B17 amorphous alloy was examined in detail, mainly by means of small-angle X-ray scattering (SAXS) measurements, and the electron density-density correlation derived from the observed intensity had the following characteristic features: a strong correlation concentrated in the short radial distances within about 1.2 nm and a rather weak correlation towards larger distances.
Abstract: The structure of an Fe83B17 amorphous alloy was examined in detail, mainly by means of small-angle X-ray scattering (SAXS) measurements. The electron density-density correlation derived from the observed intensity had the following characteristic features: a strong correlation concentrated in the short radial distances within about 1.2 nm and a rather weak correlation towards larger distances. After quantitative analysis, it was concluded that a compositional fluctuation occurs on a fine scale of about 1 nm in the amorphous Fe-B alloys, even though phase separation is not present as completely as in the structure model proposed by Boudreaux. Electrical resistivity measurements as well as transmission electron microscope (TEM) observations were performed to investigate the crystallization process. By using the theoretical equation of electrical resistivity reported by Landauer, the temperature dependence for the partially aged amorphous alloys was analysed. The volume fraction of crystalline phase estimated from the present analysis was in good agreement with the results obtained from TEM observation.
TL;DR: In this paper, transmission electron microscopy of Pb(Zr0.52Ti0.48)O3 sintered with 3 wt% excess PbO indicates that there is an amorphous grain-boundary phase 10 nm thick.
Abstract: Transmission electron microscopy of Pb(Zr0.52Ti0.48)O3 sintered with 3 wt% excess PbO indicates that there is an amorphous grain-boundary phase 10 nm thick. The grain-boundary phase has a higher Pb content than the bulk material. Influence of such a phase on sintering is discussed.
TL;DR: In this article, the authors used tetramethyltin as a starting compound for the film-forming experiments and showed that the resulting films contain carbon, tin and hydrogen with a carbon-to-tin atomic ratio of 2.5 or less.
TL;DR: In this article, thin films containing a homogeneous dispersion of small gold particles were formed by co-sputtering composite targets of gold with Al 2 O 3 and polyester in separate experiments.
TL;DR: The use of colloidal gold markers has been studied in light and fluorescent microscopy, and many applications in scanning and transmission electron microscopy as discussed by the authors, where gold markers can be produced in different sizes and can be labelled with macromolecules which keep their specific properties.
Abstract: Colloidal gold is orange to red, displays electron-opaque properties and is capable of strong emission of secondary electrons. As gold particles can be produced in different sizes and can be labelled with macromolecules which keep their specific properties, gold markers have found uses in light and fluorescent microscopy, and many applications in scanning and transmission electron microscopy.
TL;DR: In this paper, an epitaxial tellurium dioxide layer was observed on an oxidized surface of a cadmium telluride single crystal, and the structure of the oxide layer was determined using high-resolution transmission electron microscopy (TEM) and identified as that of the mineral tellurite (TeO2).
Abstract: An epitaxial tellurium dioxide layer has been observed on an oxidized {110} surface of a cadmium telluride single crystal. The structure of the oxide layer has been determined using high‐resolution transmission electron microscopy (TEM) and identified as that of the mineral tellurite (TeO2). The interface is abrupt and coherent throughout the observed region. Crystallographic relationships at the interface suggest a model for oxidation.