bluuebunny/crossref_metadata_2025 huggingface dataset:
Immunoelectron microscopic confirmation of the binding specificity of a rat anti-murine Type I pneumocyte monoclonal antibody
Authors: Hotchkiss Jon A. , Kennel Stephen J. , Harkema Jack R.
Published: June 2020

Pulmonary alveolar are lined by an epithelium comprised of alveolar type I and type II pneumocytes. Alveolar type II cells synthesize and secrete pulmonary surfactant and are progenitor cells for type I cells. Although type I cells represent only 5% to 8% of the total cells in the lung, they cover more than 95% of the alveolar surface. Perhaps as a result of their large surface to volume ratio, type I cells may be damaged by a wide range of inhaled chemicals and gases, including high concentrations of oxygen often used in respiratory therapy.

We produced a panel of rat monoclonal antibodies (MoAb) that bind specifically to cells and structural components in normal and fibrotic murine lungs. Light microscopic analysis of immunoperoxidase-stained lung sections from normal Balb/c mice suggested that one MoAb, 411-52, bound specifically to type I pneumocytes. MoAb 411-52 is a rat IgM antibody, as determined by its reactivity with class-specific anti-rat Ig antisera. The morphology of type I cells makes it difficult, if not impossible, to unequivocally identify a type I cell paraffin-embedded tissue sections. Therefore, we used immunoelectron microscopy to determine the cell binding specificity of this MoAb.
ATPase activities are restricted to the apical and lateral domain of the plasma membrane in parathyroid cells
Authors: Wild P. , Schraner E.M.
Published: June 2020

The cytoplasmic calcium concentration is about 10-7 mol, that of the extracellular space 10-3 mol. There is evidence that Ca++-ATPase is directly and indirectly involved in the maintenance of this gradient. Ca++-ATPase was found in isolated parathyroid (PT) cell membranes considering that a substantial proportion was bound to the plasma membrane (Bess et al. 1983). We, therefore, intended to localize Ca++-ATPase activity in situ. Cytochemical demonstration revealed Ca++-ATPase to be present at the apical and lateral domain of the plasma membrane in bovine PT cells.

Bovine PT glands were harvested immediately after slaughter, washed in ice cooled PBS, disected and immersed in 2% formaldehyde and 1% glutaraldehyde in 0.1M Na-cacodylate, pH 7.4, for 1 hour at 4°C. After washing or storage (maximal 24 hours), 50 μm sections were cut on a vibratome, incubated for demonstration Ca++-, Mg++-, and Na+- K+- dependent ATPase activity, post fixed with 1% OsO4 and processed for electron microscopy.
An immunocytochemical study of maternal immunoglobulin localization in the suckling pig intestine
Authors: Kömüves László G. , Turner Donna S. , McKee Kathy S. , Nichols Buford L. , Heath Julian P.
Published: June 2020

In this study we used colloidal gold probes to detect the intracellular localization of colostral immunoglobulins in intestinal epithelial cells of newborn piglets.

Tissues were obtained from non-suckled newborn and suckled piglets aged between 1 hour to 1 month. Samples were fixed in 2.5 % glutaraldehyde, osmicated and embedded into Spurr’s resin. Thin (80 nm) sections were etched with 5% sodium ethoxide for 5 min, washed and treated with 4 % sodium-m-periodate in distilled water for 30 min. The sections were then first incubated with blocking buffer (2 % BSA, 0.25 % fish skin gelatin, 0.5 % Tween 20 in 10 mM Trizma buffer, pH=7.4 containing 500 mM NaCl) for 30 min followed by the immunoreagents diluted in the same buffer, 1 hr each. For the detection of pig immunoglobulins a rabbit anti-pig IgG antiserum was used followed by goat anti-rabbit IgG-Au10 or protein A-Au15 probes.
Characterization of an optimal protein A-gold complex: Improvement of the labeling efficiency
Authors: Ghitescu Lucian , Bendayan Moise
Published: June 2020

By using 125I protein A, we have prepared complexes of this immunoprobe with colloidal gold particles having diameters ranging from 5 to 15 nm. Various concentrations of protein A (from 35 to 1000 nM) of known specific activity were employed in order to obtain a spectrum of conjugates differing not only in sizes, but also in amounts of protein A they carry. After ultracentrifugation through a step gradient (15, 30 and 70% w/v) of sucrose, the protein A-gold complexes were quantitatively recovered from the most dense layer, and diluted in a 0.01 M phosphate buffer containing 0.01% polyethylene glycol. The conjugates did not contain free protein A, as proven by the lack of radioactivity in the intermediate sucrose layers. By correlating the radioactivity of the complexes with their particle densities (inferred from the optical absorbance at 520 nm), the number of protein A molecules bound per gold particle was calculated for each experimental condition.
Immunocytochemical localization of β1-4 galactosyltransferase in endometrial carcinoma cells
Authors: Yamamoto Ichiro , Tachibana Toshiaki , Maruyama Hiroko , Komatsu Noriyuki , Kuramoto Hiroyuki , Narimatsu Hisashi
Published: June 2020

We have paid attention to the alteration of glycosyltransferase in carcinoma cells, because it might be related to the malignancy of the cells. In this connection, localization of β1-4 galactosyl transferase (β1-4 Gal T) in human endometrial carcinoma cells was examined immunocytochemically using two kinds of cell lines, each of which showed different degree of differentiation.

An antibody was purified from the rabbit antiserum against the synthetic peptide, IFNRLVFRGMSC (W89) of human β1-4 Gal T coupled with KLH (keyhole limpet hemocyanine) by protein A column and peptide-affinity column chromatography. The anti-W89 serum reacts to the C-terminus of human β 1-4 Gal T and to both membrane-bound and soluble forms of the enzyme. Cell line of well differentiated endometrial adenocarcinoma (I) and that of poorly differentiated endometrial adenocarcinoma (50B) were cultivated respectively in MEM medium containing 15% FCS and 2 mM glutamine for 4 d at 37°C under 5% CO2. The cells were fixed in a mixture of 4% paraformaldehyde and 0.1% glutaraldehyde in 0.1 M Soerensen’s phosphate buffer (pH 7.4) at 4°C for 30 min, washed with PBS, then freezed and thawed. The indirect method of the peroxidase- labeled antibody technique was used for immunocytochemistry of both LM and TEM on the cell lines. The cells were dehydrated in ethanol and embedded in TAAB 812. Ultrathin sections were observed under a TEM, JEM-100S.
Desmosomal Disorganization and Epidermal Abnormalities in a Transgenic Mouse Expressing Mutant Desmoglein-3.
Authors: Yu Qian-Chun , Allen Elizabeth , Fuchs Elaine
Published: June 2020

Desmosomes are special adhesion structures connecting epithelial cells. The formation of desmosome plaques requires the participation of multiple molecules including desmoplakin (DP), plakoglobin (PG), desmocollins (DSC), and desmogleins (Dsg). It is known that Dsg has functional domains involved in cell-cell adhesions and plaque-cytoskeleton interactions. Functional modulation of Dsg is known to be related to some skin disorders exhibiting desmosome abnormalities. To better understand the role of Dsg 3 in the assembly of epidermal desmosomes and its possible relation to cutaneous disorders, we generated a transgenic mouse model which, driven by a keratin 14 promoter, expressed high levels of a truncated Dsg 3, Dsg3ΔN, in the lower epidermal keratinocytes.

Skin samples of different body sites were collected, at different ages, from both control mouse and mutant animals exhibiting phenotypic skin changes for histology, immunohistochemistry, and ultrastrucutral studies. Specimens for conventional TEM studies were fixed in 4% paraformaldehyde and 2.5% glutaraldehyde, post-fixed in 1% OsO4, and embedded in LX-112. For immunoelectron microscopy, samples were fixed in 2% paraformaldehyde and 0.05% glutaraldehyde, dehydrated in ethanol at -25°C, embedded in Lowicryl K4M medium, and polymerized at -25°C with UV light. Ultrathin sections were labeled with several antibodies against DP, PG, DSC, and E-cadherin. All sections were stained with uranyl acetate and lead citrate before examining with a JEOL-CX microscopy operated at 60 kv.
Determination of the interface structure of CdTe(111) ON Si(100) using Z-contrast imaging and EELS
Authors: Wallis D. J. , Nellist P. D. , Sivananthan S. , Browning N.D. , Pennycook S.J.
Published: June 2020

The epitaxial growth of dissimilar materials, or hetroepitaxy, is of great technological interest for a variety of reasons. Perhaps the most obvious of these is that high quality, large area substrates are unavailable for many materials. It is therefore necessary to resort to growing the material of interest on a dissimilar substrate. However, this procedure introduces its own problems, such as differences in crystal structure and mechanical properties of the substrate and film materials. Understanding the structural aspects of this growth process is a critical step towards the production of high-quality and reliable integrated device structures.

One system of current interest for application into diverse electron-optical devices is HgCdTe. HgCdTe is a semiconductor whose band gap may be tailored by the concentration of Hg giving it applications as X-ray and g-ray detectors and also in solar cells. The first stage in developing integrated technology for this material is the production of a high-quality substrate. For this task, CdTe seems an ideal choice. However, CdTe itself does not exist in a form that immediately lends itself for use as a substrate and hence must be prepared by heteroepitaxy.
On interpreting weak beam images of microtwins
Authors: Kim H. S. , Sheinin S. S.
Published: June 2020

The concept of a dynamically coupled set is of fundamental importance in carrying out theoretical calculations of image contrast of microtwins. Up to the present, considerations based on the dynamical theory have indicated that the diffracted beams taken into account in a particular calculation of image contrast must always reside in the same dynamically coupled set. The work presented in this paper indicates that for weak beam images this may not the case. The reason for this can be seen from Fig.1b in whichg, hand (i), (j) are reciprocal lattice vectors and branches of the dispersion surfaces in the matrix and microtwin respectively. It can be seen that if the condition (h − g) = Δγnfis obtained then the Bloch wave vectors in the matrix and twin,and, are parallel. Under these circumstanceswill make a coherent contribution to the intensity of diffracted beam g, even though h does not reside in the same dynamically coupled set.
Dislocation detection depth measurements in silicon using electron channelling contrast imaging
Authors: Simkin B. A. , Crimp M. A.
Published: June 2020

Electron Channelling Contrast Imaging (ECCI) employs local differences in backscatter yield due to local changes in the lattice orientation relative to the electron beam to provide imaging contrast. Due to the low contrast levels typically obtained for dislocations from this mechanism, efforts to enhance the signal to noise by tilting the specimen to high angles, signal averaging, or energy filtering are common.

Determination of the depth to which individual dislocations can be imaged via ECCI in bulk samples has not previously been attempted by stereo imaging measurements due presumably to the common experimental setup of a high tilt angle. Previous measurements of dislocation detection depth have relied upon sample geometry to approximate detection depths by estimating the dislocation diving angle based on the approximate line direction and surface normal, and were preformed using acceleration voltages not typical of most SEM work. In this investigation, dislocations were imaged employing stereo pairs at near normal sample inclination at an accelerating voltage of 25kV. The reduction in signal to noise at normal sample incidence is believed to be more than offset by the ease of sample manipulation due to the reduction of detector viewing geometry restrictions imposed by the high tilt configurations most commonly seen.
X-ray microscopy: A novel, low damage approach to core excitation spectroscopy at high spatial resolution
Authors: Ade H.
Published: June 2020

Only recently has transmission x-ray microscopy been utilized for chemical analysis from small spots and chemical mapping via near edge x-ray absorption fine structure (NEXAFS) spectroscopy. NEXAFS microscopy is analogous to Electron Energy Loss Spectroscopy (EELS) in an electron microscope. Particularly in imaging mode, NEXAFS microscopy requires a considerable lower dose than EELS microscopy which makes it very suitable to studying radiation sensitive materials such as polymers. In addition, NEXAFS microscopy can exploit the dependence of x-ray absorption resonances on the bond orientation relative to the linearly polarized x rays (linear dichroism microscopy) and determine the orientation of specific chemical bonds in (partially) orientated materials.
Selective Corrosion of brazed joint between BNi-2 filler metal and stainless steel 316
Authors: Kim H. S. , Lee R. U.
Published: June 2020

A heating element/electrical conduit assembly used in the Orbiter Maneuvering System failed a leak test during a routine refurbishment inspection. The conduit, approximately 100 mm in length and 12 mm in diameter, was fabricated from two tubes and braze-joined with a sleeve. The tube on the high temperature side (heating element side) and the sleeve were made of Inconel 600 and the other tube was stainless steel (SS) 316. For the filler metal, a Ni-Cr-B brazing alloy per AWS BNi-2, was used. A Helium leak test spotted the leak located at the joint between the sleeve and SS 316 tubing. This joint was dissected, mounted in a plastic mold, polished, and examined with an optical microscope. Debonding of the brazed surfaces was noticed, more pronounced toward the sleeve end which was exposed to uncontrolled atmospheric conditions intermittently. Initially, lack of wetting was suspected, presumably caused by inadequate surface preparation or incomplete fusion of the filler metal. However, this postulation was later discarded based upon the following observations: (1) The angle of wetting between the fillet and tube was small, an indication of adequate wetting, (2) the fillet did not exhibit a globular microstructure which would be an indication of insufficient melting of the filler metal, and (3) debonding was intermittent toward the midsection of the sleeve.
Nano-characterization of Rh-Sn bimetallic catalysts
Authors: Crozier P.A. , Claus P.
Published: June 2020

Bimetallic catalysts are of considerable importance because they possess both high activity and selectivity. Recently, there has been considerable interest in bimetallic catalysts produced by surface organometallic chemistry on metals. A detailed description of the structure and composition at the nanometer level is critical to fully understand the behavior of such catalysts. We have undertaken a study of the microstructure of Rh-Sn/SiO2 bimetallic hydrogenation catalysts.

A Rh-Sn precursor was prepared by reacting tetrabutyltin with a silica supported Rh parent catalyst (1 %Rh/SiO2). The bimetallic catalysts were produced by thermal decomposition of the precursor in flowing hydrogen at 623 K. Five different catalysts were produced with a range of different Sn loadings from Rh(1%)/SiO2 to Rh(1%)-Sn(1.85%)/SiO2. The resulting bimetallic catalysts were able to selectively hydrogenate isolated and conjugated C=O functional groups. In situ XPS showed that the Sn and Rh were in the fully reduced state. Mossbauer spectroscopy studies confirmed that Sn was present in the zerovalent state indicating that no oxidized Sn was present. Preliminary IR data suggests that most of the Rh atoms are isolated from their neighbors (presumably by Sn).
Chemistry, Bonding and Mechanical Properties of Grain Boundaries in Intermetallic Compounds
Authors: Subramanian Shanthi , Muller David A. , Silcox John , Sass Stephen L.
Published: June 2020

Grain boundaries in ordered intermetallic compounds have a great influence on their mechanical properties. Considerable progress has been made on characterizing the chemistry at grain boundaries experimentally and understanding their electronic structure theoretically. The approach in the present study is to experimentally examine the bonding changes at grain boundaries, in the presence and absence of dopants, using Electron Energy Loss Spectroscopy (EELS), and interpret these changes in terms of the observed mechanical properties.

EELS of transmitted electrons probes excitations which occur at unique energy losses. In the present study, the Ni L2,3 edges were examined which select excitations from the Ni 2p orbitals to states above the Fermi level. For single electron excitations, it can be shown that the area under the sharp peaks at the onset of the L2,3 edges is proportional to the number of holes in the Ni d band for the 3 d transition metals. Fig. 1 shows the EELS spectra from bulk Ni, Ni3Al and Ni3Si. The edge intensity (historically called a white line) is reduced in Ni3Si and Ni3Al with respect to Ni.
Towards Optimization of Grain-Boundary Structures in Annealed Nickel
Authors: Thomson C.B. , Randle V.
Published: June 2020

Many properties of materials are influenced by intergranular structure. Increasing the number of grain boundaries with favourable properties, or ‘special’, boundaries, can enhance the performance of a material in service. However, the criteria that must be satisfied for a boundary to be classified as special are not widely understood. For example, it has been shown that Σ3 coincidence site lattice (CSL) boundaries alone present a resistance to corrosion greater than for other boundary types in nickel (fee). In contrast, Rolim Lopes et al. observed no statistical preference for Σ3s in the grain boundary network of FeAl (bcc), and Bouchet and Priester discovered that in nickel there was a weak propensity for segregation to several boundary types, including Σ3, Σ1 1 and Σl9a CSLs.

Commercially pure and superpure nickel specimens have been subjected to the strain annealing treatments detailed in the Table. Fig. 1 shows the results from an electron backscatter diffraction study of the commercial purity specimens (CI to C4). It is clear that the only boundary types that increase in frequency with increased thermal processing are Σ3n (n=l,2,3) CSLs. An abundance of annealing twins was observed for sample C4, and is unique to this sample, and this accounts for the very high proportions of Σ3s. Samples CI to C3 were annealed under vacuum, whereas C4 was treated in air, and it is proposed that the dominant energy minimization mechanism has changed from grain/grain boundary rotation for samples CI to C3, to annealing twin formation for sample C4. If the structure of a grain boundary evolves towards the exact misorientation of what is considered a special CSL type, the special properties of that boundary will, in general, become more marked. Σ3s have been shown to possess special properties. Fig. 2 shows the average deviation from exact misorientation for the Σ3s in each sample, normalised by the Brandon criterion for maximum permitted deviation. This clearly indicates that the Σ3s created by annealing twin formation can be considered more special than those produced via grain/grain boundary rotations.
Metal Microstructures in Advanced CMOS Devices
Authors: Gignac L. M. , Rodbell K. P.
Published: June 2020

As advanced semiconductor device features shrink, grain boundaries and interfaces become increasingly more important to the properties of thin metal films. With film thicknesses decreasing to the range of 10 nm and the corresponding features also decreasing to sub-micrometer sizes, interface and grain boundary properties become dominant. In this regime the details of the surfaces and grain boundaries dictate the interactions between film layers and the subsequent electrical properties. Therefore it is necessary to accurately characterize these materials on the proper length scale in order to first understand and then to improve the device effectiveness. In this talk we will examine the importance of microstructural characterization of thin metal films used in semiconductor devices and show how microstructure can influence the electrical performance. Specifically, we will review Co and Ti silicides for silicon contact and gate conductor applications, Ti/TiN liner films used for adhesion and diffusion barriers in chemical vapor deposited (CVD) tungsten vertical wiring (vias) and Ti/AlCu/Ti-TiN films used as planar interconnect metal lines.
Electron Microscopy Analysis of Grain Boundary Structure and Composition in Superplastically Deformed Al-Mg Alloys
Authors: Vetrano J. S. , Bruemmer S. M.
Published: June 2020

Evaluation of grain boundary composition and structure in superplastically deformed AA5083-based alloys (AI-4.5Mg-1.6Mn-0.2Zr) was carried out in a field-emission gun transmission electron microscope (FEG-TEM). During superplastic deformation at high homologous temperatures materials undergo extensive grain boundary sliding (GBS) which creates a flow of defects in the near-boundary region. Recent literature has shown that the grain-boundary composition in Al-Mg alloys is not necessarily the same as the matrix, and that these differences can have an effect on GBS.

Two alloy conditions were tested, with slightly different particulate content and superplastic deformability. Samples were tested at temperatures of 400°C and 450°C and a strain rate of 1x10-−3s−1 to vary the degree of grain boundary sliding, then quenched under load to preserve as much of the high-temperature structure as possible. TEM samples were prepared by carefully punching disks from the gage section of the deformed sample and electropolishing. Additionally, one sample was brought up to temperature and quenched but not deformed.
Integrated Microscopy : From Design Philosophy to Applications
Authors: Tremblay Sébastien , Baril Éric , St-Pierre Éric , Ronaldi Jacques , L’Espérance Gilles
Published: June 2020

Microscopy and Objects

Object oriented programming (OOP) has been used to develop computer applications for many years. It has proven very efficient for the manipulation of data structures that share common elements and evolve over time. We observed that this approach might prove invaluable for microscopy where we, as researchers, developers and end-users, have to deal with many media (images, spectra, electrical measurements, databases, simulations, etc.) to accomplish a given characterization project. Particularly, since these media evolve as researchers find new techniques and manufacturers improve their instruments. In addition, the goals and aims of a project may also change with time. The ability to reuse information that has already been acquired/generated then becomes crucial to success since this avoids the cost of repeating an analysis when information that was considered unimportant suddenly becomes of interest. In this context all results, acquisition parameters, instrument and processing tool settings, are relevant. The need for modularity, completeness and adaptation of information guided our design for the information structure used to develop the integrated characterization system. It is based on 3 types of small data objects. The first type carries the properties of each physical object (microscope, EDX spectrometer, specimen stage, sample, etc.). The second type carries acquired data such as images, spectra, etc. Finally, the last type of small data object carries the processed results such as hardness, composition, features sizes, distribution, etc. A characterization project can then be represented like any compound document as shown in figure 1. This architecture can be used inside applications as well as with storage devices (where objects are saved in compound files). Those objects can also contain hierarchy information such as the relationship between objects (i.e. “is subset of, , “is generator of, or “is defined by”).
The Teaching SEM - An Example of Real-Time Remote Control SEM
Authors: Mansfield John F.
Published: June 2020

To introduce engineering undergraduates to one of the most widely used microstructural characterization tool, namely the scanning electron microscope (SEM), the Department of Materials Science and Engineering (MS&E) at The University of Michigan has developed the Teaching SEM. This instrument is located in the department’s undergraduate teaching laboratory, however, it may be controlled from a lecture theater or classroom virtually anywhere on the University campus, or indeed, anywhere within the reach of the campus computing network and cable television network. The Teaching SEM allows MS&E to incorporate live SEM demos in the large service courses it teaches to engineering students and to show entire classes of MS&E majors how to control the microscope that tfiey subsequently use in their laboratory practicals.

The Teaching SEM has been developed with hardware and software that is readily available, and there has been no custom software development or manufacture of specialized hardware. In addition to being a novel teaching tool, it also demonstrates the ease with which it is possible to do “Telepresence Microscopy”.
Molecular Imaging: Design of the PMP Imaging Spectrometer, Resolution Limits, and Radiation Sensitivity
Authors: Barfels M.M.G. , Heng Y. , Ottensmeyer F.P.
Published: June 2020

One of the main applications of an energy filter is to obtain elemental distribution images by electron spectroscopic imaging. This technique has been pushed to the imaging of fine structure such as the sp2 and sp3 states of carbon at a sub-nanometer spatial resolution. However, low energy loss imaging in the region of the molecular excitations has largely remained unexplored due to the limitation in the energy resolution obtainable in the energy filters. Molecular absorptions in the visible and UV regions of the spectrum occur at 1.5 eV to 10 eV. Thus it would be necessary to have an energy resolution of about 1 eV or better.

An optimized Prism-Mirror-Prism energy filter has been built by altering the straight faced pole pieces to circular curvatures. See Figure 1. The optimum curvatures for each of the faces were determined iteratively. In order to simulate the electron path accurately through the Prism-Mirror-Prism filter, it was necessary to calculate the magnetic fringing fields using the Boundary Element Method as outlined by Kasper. The ray-tracing procedure indicated a theoretical energy resolution of 1.3 eV for the optimized magnetic prism. This has been tested on our prototype spectrometer currently installed in the Siemens EM 102. An energy resolution of 1.1 eV was obtained.
Computational Micrograph Registration with Sieve Processes
Authors: Phillips P.J. , Huang J. , Dunn S. M.
Published: June 2020

In this paper we present an efficient algorithm for automatically finding the correspondence between pairs of stereo micrographs, the key step in forming a stereo image. The computation burden in this problem is solving for the optimal mapping and transformation between the two micrographs. In this paper, we present a sieve algorithm for efficiently estimating the transformation and correspondence.

In a sieve algorithm, a sequence of stages gradually reduce the number of transformations and correspondences that need to be examined, i.e., the analogy of sieving through the set of mappings with gradually finer meshes until the answer is found. The set of sieves is derived from an image model, here a planar graph that encodes the spatial organization of the features. In the sieve algorithm, the graph represents the spatial arrangement of objects in the image. The algorithm for finding the correspondence restricts its attention to the graph, with the correspondence being found by a combination of graph matchings, point set matching and geometric invariants.
Development of a High-Speed Optical Microscope Auto-Focus Control System for EPMA
Authors: Notoya S. , Saito M. , Matsuya M. , Ishii T. , Murakami K. , Ohashi H. , Nielsen C.
Published: June 2020

This paper reports the new development of an optical microscope automatic focus control system (OMAFD) for the JXA-8800/8900 series Electron Probe Microanalyser (EPMA). In recent years, a method called “wide area mapping” has been increasingly used with EPMA for measurement of X-rays by moving the specimen to obtain 2-dimensional element distributions over large analysis areas. In mapping, the simultaneous acquisition of multiple elements is required. Using an optical microscope, which has a very small (about ±1 μm) depth of focus, the specimen surface needs to be vertically adjusted to the Rowland circle of a wavelength dispersive X-ray spectrometer. Even with flat specimens, actual analysis points often show some inclination. Specimens are often inclined accidentally during sample preparation and mounting. Moreover, requirements of specimen analysis with curved or irregular surfaces have been increasing.
Windows Remote Control for the Philips CM Microscope
Authors: Otten Max T.
Published: June 2020

New software has been developed to make it possible to control the CM microscope under Windows. The software structure is such that all programs communicate through a dynamic link library CMREMOTE.DLL and communication program SECS2.EXE with the microscope (Fig. 1). Due to this structure, the amount of memory required is minimised since functional duplication is avoided, and the remote control handling is simplified because the user programs do not need to handle the complicated communication protocol but instead use simple functions such as Get Alignment and CompuStage Goto Position. Several sets of programs are finished, with further additions planned to replace currently available software running under MS-DOS.

Available at the moment is the Windows CM Remote Control package which contains the Windows CM Monitor, a program to read alignments, stigmator settings and mode settings from microscope and store them in a file on the PC. With the file are stored an operator name and comments to allow identification who stored the data and for what reason.
Ultra-High Resolution with The Jem-2010F Field-Emission Tem
Authors: Hosokawa F. , Tomita T. , Honda T. , Kersker M.
Published: June 2020

Historically, high probe current in small probes has been the principal virtue of the field emission TEM. Analytical performance is greatly enhanced[1] and fine probe mapping an important analytical tool for trace element segregation and very fine scale high resolution chemical imaging. Less appreciated is the enhanced high resolution capability due to the small energy spread of the electron source and higher coherency due to reduced primary and virtual source size. The envelope function of the phase contrast transfer function (PCTF) is drastically improved reducing image blurring due to both chromatic aberration and specimen illumination angle. This is especially true for the high spatial frequencies beyond the first zero. Intensities sufficient for image formation can be obtained from these higher frequency regions. Since the PCTF does not change its form, photographing images at the Scherzer condition will yield higher resolution with higher coherency, however, the transfer of the specimen potential corresponding to contrast enhanced regions is in the oscillations form beyond the first zero. Changes in the defocus will lead to changes in transferred frequencies beyond the first zero and possible extinctions of otherwise transferred information since the oscillations will pass through zero contrast. Interpretation of images under these conditions will, therefore, require accurate measurement of the optical parameters of the microscope and especially accurate measurements of the defocus conditions. It is also important to calculate images under these conditions for comparison with measured images which give the insurance of defocus conditions supposed to be presented.
Light-Element EPMA—Correlations, convolutions, and true concentrations
Authors: Kracher Alfred , Flumerfelt Joel F. , Anderson Iver E.
Published: June 2020

Analyses of small concentrations of light elements by electron microprobe are complicated by a number of factors, including low signal strength and line overlap. Obtaining reliable data may require techniques that are uncommon in wavelength-dispersive (WDS) x-ray analysis. A case in point is the investigation of alloys that contain small amounts of nitrogen. Nitridation of Al metal and Al alloys with N-bearing gaseous species is being studied as a way to form in situ nitride precipitates, which is of interest for altering the mechanical properties of these materials. It was found, for example, that one specific alloy with 1.7 wt% Ti and 7.7 wt% Y retains much larger N concentrations on nitridation than pure Al, using the same processing conditions for both alloys. Nitrogen may be present in TiAl3 precipitates, YA13 precipitates, or the matrix. Identifying the N-bearing compound by EPMA has proven difficult, however, because of the interference of Lℓ on N Ka, combined with the low peak/background ratio of the N Ka peak.
A New Numerical Model for Electron-Probe Analysis at High Depth Resolution
Authors: Staub P.-F. , Bonnelle C. , Vergand F. , Jonnard P.
Published: June 2020

Characterizing dimensionally and chemically nanometric structures such as surface segregation or interface phases can be performed efficiently using electron probe (EP) techniques at very low excitation conditions, i.e. using small incident energies (0.5<E0<5 keV) and low incident overvoltages (1<U0<1.7). In such extreme conditions, classical analytical EP models are generally pushed to their validity limits in terms of accuracy and physical consistency, and Monte-Carlo simulations are not convenient solutions as routine tools, because of their cost in computing time. In this context, we have developed an intermediate procedure, called IntriX, in which the ionization depth distributions Φ(ρz) are numerically reconstructed by integration of basic macroscopic physical parameters describing the electron beam/matter interaction, all of them being available under pre-established analytical forms. IntriX’s procedure consists in dividing the ionization depth distribution into three separate contributions:
The determination of the thickness and composition of multilayered thin films in the SEM by x-ray microanalysis with Monte Carlo simulations
Authors: Gauvin Raynald , Caron Mario , Hovington Pierre , Drouin Dominique , Gagnon Gilles , Currie John F.
Published: June 2020

X-Ray microanalysis is now a well established technique to determine the composition and the thickness of multilayer structures of different materials. The most popular software used to quantify such system are based on analytical φ(ρz) curves which are approximation of the x-Ray generation process. The computed φ(ρz) curves of multilayered samples are based on mixtures rules and weight functions which are not always accurate. In this paper, Monte Carlo simulations of electron trajectories in solids are used to compute φ(ρz) curves in multilayered specimens directly and then used to computed the K ratios.

To validate this procedure, a TiN(100 nm)/Ti(10 nm) multilayer metallization structure deposited on SiO2(100 nm)/Si substrate was used in conjonction with a TiN(400 nm)/Si standard sample. This system is a very active field of research and development in the microelectronics industry. The thicknesses, composition and microstructure of both systems were fully characterized by Elastic Recoil Detection (ERD), X-ray diffraction (XRD) and Transmission Electron Microscopy (TEM).
Characterization of lead-bearing phases in municipal waste combustor fly ash
Authors: Sutter L. L. , Dewey G. R. , Sandell J. F.
Published: June 2020

Municipal waste combustion typically involves both energy recovery as well as volume reduction of municipal solid waste prior to landfilling. However, due to environmental concerns, municipal waste combustion (MWC) has not been a widely accepted practice. A primary concern is the leaching behavior of MWC ash when it is stored in a landfill. The ash consists of a finely divided fly ash fraction (10% by volume) and a coarser bottom ash (90% by volume). Typically, MWC fly ash fails tests used to evaluate leaching behavior due to high amounts of soluble lead and cadmium species. The focus of this study was to identify specific lead bearing phases in MWC fly ash. Detailed information regarding lead speciation is necessary to completely understand the leaching behavior of MWC ash.
Density of states calculations for Ni-Al Alloys
Authors: Alvarez Jose R. , Rez Peter
Published: June 2020

Impurities at grain boundaries can have dramatic effects on the ductility or embrittlement of metals and metallic alloys. The mechanism for these effects is controversial, but it is believed that charge redistribution induced by the impurity atoms is responsible. Electron energy loss spectroscopy (EELS) in the scanning transmission electron microscope (STEM) can be used to measure changes in unoccupied densities of states (DOS) when a small nanometer sized probe is moved across a grain boundary. To interpret the energy loss fine structure band theory is needed to relate the observations, which represent an angular momentum resolved density of states at a particular atomic site, to the local electronic structure in the material.

We compare the Linearized Augmented Plane Wave (LAPW) and layered Korringa-Kohn-Rostoker (LKKR) methods for calculating densities of states relevant for energy loss in Ni-Al alloys. Both methods can give the angular momentum resolved densities of states at a particular site and both use the Local Density Approximation (LDA). The LAPW method allows ab initio electronic structure calculations of materials by introducing atomic spheres where the basis wave functions are approximated by solutions of a radial potential; for the interstitial region between the atoms the basis wave functions are approximated by plane waves.
Recent Progress in Alchemi Analysis
Authors: Anderson Ian M. , Bentley J.
Published: June 2020

The scope of microanalysis encompasses a variety of the charactersitics of a small volume of material, from its composition to its electronic structure. One such characteristic is the local environment of the elements in the volume, including the identity and coordination of the near-neighbors of each element. For multisublattice crystals, this level of the chemistry is characterized by the site-occupancies of the elements composing the crystal. Atom-location by channeling-enhanced microanalvsis (ALCHEMI) is a powerful technique for the experimental measurement of tiiese site-occupancies. Following its introduction, ALCHEMI enjoyed initial successes for the study of cation distributions in oxide minerals. However, the technique was prone to large systematic errors for analyses that required soft (≤ 4 keV) X rays, because of so-called ionization delocalization. Improvements to the original formulation of ALCHEMI have aimed to improve the low statistical confidence level of the technique, to explicitly address ionization delocalization, and to correct for anti-site defects. The present paper will illustrate these improvements while emphasizing the basis underlying ALCHEMI analysis.
Quantitative high-spatial-resolution microchemical analysis of Fe-Co-Ni transformation-toughened steels
Authors: Lippard H. E. , Dravid V.P. , Olson G.B.
Published: June 2020

Superior strength-toughness combinations can be obtained in AerMet100 by an austenite→martensite phase transformation of small intralath austenite precipitates. The enhanced toughness in these alloys has been attributed to the presence of “metastable” austenite precipitates, the stability of which is intimately related to the size and composition. The austenite precipitates require high stability to resist transformation under all stress conditions except when in the triaxial stress field of a crack tip. The two primary factors determining austenite stability are size and composition. Thus the microstructure-property correlations and further alloy development require quantitative microchemical analysis of austenite precipitates in the 4-10nm size range.

Of the possible analytical techniques, only analytical electron microscopy (AEM) and atom probe-field ion microscopy (AP-FIM) merit consideration by achieving quantitative composition analysis with very high spatial resolution. After exploring both avenues, AEM was chosen as the analytical technique based on its superior speed, counting statistics, and versatility.
Widefield digital images in biological transmission electron microscopy (TEM) obtained by automatic image montage
Authors: Haug F.M.S. , Desai V. , Laake J. , Nergaard P.O. , Ottersen O. P.
Published: June 2020

A transition to digital recording is taking place in microscopy, including TEM. Biological TEM often requires nanometer resolution within micrometer fields of view, i.e., image widths between 1 and 5 (10) Kpixels in digital terms. Electron dense particles between 1 and 15 nm are used in immunolabelling and in neurohistology, micrometer-sized objects such as synaptic boutons or glial processes are often studied with a need to clearly resolve membranes and filaments.

We needed larger fields of view in an image processing system (IPS) to quantify neuroactive amino acids in immunogold labelled ultrathin sections. At startup of our project (1991) megapixel cameras for TEM were few and expensive and we designed a system for on-line image montage.

A Gatan 673 Mk3 Wide angle TV camera is adapted to the lateral port of a Philips CM10 TEM. Pixel noise is reduced by frame averaging in a fully equipped Matrox Image 1280 board (EISA version) that also supports variable offset and gain of the analogue signal, real time mapping of gray values 0 and 255 to specific colours, and full handling of 1280 × 1024 pixel images.
Differential contrast imaging with differential hysteresis processing
Authors: Peters Klaus-Ruediger
Published: June 2020

The spacial information of images can be characterized with contrast patterns. We analyzed the spacial contrast distribution in micrograph data with differential hysteresis processing using a PiXISION-AP128 imaging workstation (JEOL USA Inc., Peabody, MA) and found that discrete spacial image components have discrete contrast characters which are defined by specific contrast levels and specific contrast ranges. Consecutive contrast segmentation at increasing contrast levels produced a limited number of contrast patterns which were discretely recognizable and distinguishable. These contrast patterns have an unique accumulative property, i.e., a digital image can be segmented into contrast patterns and reassembled from its contrast patterns. Contrast patterns can be mathematically defined by a differential hysteresis range (DHR). The DHR (DHR x-y) describes differential contrasts of a pattern with two intensity values as contrasts which are larger than the first value (x) and smaller than the second value (y). The contrast patterns can be visualized as images through linear scaling to the maximum visual perception range (8-bit). The DHR provides an universal imaging parameter since it applies to all images independent of source, size, bit depth, and spacial content.
The Critical Role of Microscopy and Spectroscopy in the Development of New Materials for Microelectronics Packaging
Authors: Youngman R.A.
Published: June 2020

It has been over thirty years since sintered aluminum nitride (AIN) has been the focus of many research and development activities in Japan, the U.S., and Europe. Only in the past 5 years has there been significant use of this material in microelectronics. There are many reasons for this considerable time for application including, technology needs and acceptance of a new material. Also important has been the role of materials understanding of AIN through the use of microscopy and spectroscopy. We illustrate the use of both standard and unique characterization techniques to elucidate the nature of the crystalline defects which control the important property of thermal conductivity.

The thermal conductivity of pure AIN is 320 W/mK. This value has never been achieved in a sintered ceramic. In order to develop a sintered AIN with a high thermal conductivity it is necessary to understand the factors which control the thermal conductivity.
Construction of plastic contact deformation maps on ceramics: a case study on aluminum nitride
Authors: Callahan D. L.
Published: June 2020

Modern polishing, precision machining and microindentation techniques allow the processing and mechanical characterization of ceramics at nanometric scales and within entirely plastic deformation regimes. The mechanical response of most ceramics to such highly constrained contact is not predictable from macroscopic properties and the microstructural deformation patterns have proven difficult to characterize by the application of any individual technique. In this study, TEM techniques of contrast analysis and CBED are combined with stereographic analysis to construct a three-dimensional microstructure deformation map of the surface of a perfectly plastic microindentation on macroscopically brittle aluminum nitride.

The bright field image in Figure 1 shows a lg Vickers microindentation contained within a single AlN grain far from any boundaries. High densities of dislocations are evident, particularly near facet edges but are not individually resolvable. The prominent bend contours also indicate the severity of plastic deformation. Figure 2 is a selected area diffraction pattern covering the entire indentation area.
Characterization of boron nitride thin films synthesized by plasma-assisted chemical vapor deposition technique
Authors: Liu J. , Lin S. H. , Feldman B. J.
Published: June 2020

Boron nitride (BN) is a well-known non-oxide ceramic that has interesting and useful properties for potential industrial applications. The attractive properties of BN include its high-temperature shock stability, high electrical resistivity, anisotropic thermal conductivity and desirable mechanical properties. The potential uses of BN films include oxidation-resistant and anti-corrosive coatings, sensors, optical devices, and high temperature electronics. Thin films of BN have been obtained by a variety of growth techniques including sputtering, ion plating, evaporation, and chemical vapor deposition and associated techniques. To optimize the growth parameters and the performance of BN films, advanced electron microscopy techniques have been employed to study the structural evolution of BN films synthesized by plasma assisted chemical vapor deposition technique (PACVD).

The BN films were grown in a capacitively coupled rf plasma reactor with a feedstock of diborane (B2H6), ammonia (NH3), and hydrogen (H2). The growth parameters were the same as previously reported. Chemical analyses of the grown BN films showed that they had significantly more boron (44 at.%) than nitrogen (33 at.%) and contained a large amount of hydrogen (23 at.%).
Silicate-Glass/Sapphire Interfaces Probed with Micromechanical Testing Instruments: Sem and Tem Combined Characterization
Authors: Zagrebelny A. V. , Nelson J. C. , Ramamurthy S. , Carter C. B.
Published: June 2020

The presence of intergranular phases is a common feature in today's polycrystalline ceramics prepared through traditional sintering routes. Although it has been shown that the chemistry and the microstructure of these phases may be altered, for example, by manipulating the heat treatments to tailor the final material's properties, very little is known about the mechanical properties of the interfaces on the microscopic scale.

The mechanical behavior of the interfaces between calcium-alumino-silicate (CAS) glasses and single-crystal α-AI2O3 substrates has been studied with two different types of micromechanical testers. The emphasis of this work is to correlate irregularities observed in the load-displacement curves produced using these testing instruments with the morphology of the deformation regions observed for the microindentations and microscratches. The effect of the substrate orientation on the interfacial properties has also been studied. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) have been used to characterize the deformation structures associated with the microscratches and microindentations.