EVALUATION OF PHYSICAL AND COMPOSITIONAL CHANGES OF REPAIR ADHESIVE USING SURFACE AND INTERFACE CUTTING ANALYSIS SYSTEM

ABSTRACTThe design and performance of CHIRIBAS(Compact and High-Resolution Ion Backscattering Analysis System) are presented. The system consists of a 60 kV duoplasmatron and unique energy analysis systems connected to a microcomputer. The 5–60 keV H, He, and He+ beams are backscattered to 180° and their energies are analyzed by a time-of-flight technique or with an electrostatic deflector combined with a position sensitive microchannel plate. The probing depth and depth resolution are estimated to be up to 50 nm and better than 0.5 nm, respectively. The computer-simulated spectrum analysis allows rapid and accurate determination of surface and interface structures such as depth profiles of elemental compositions and lattice defects. CHIRIBAS also makes it possible to measure excited state populations using Stark ionization for 5–10 keV H neutralized at the exit surface and thus provides the possibility to determine the energy and spatial distributions of the valence electrons extending outward from the top surface. The present article includes the beam parameters achieved and the preliminary data on reactive-ion etched Si surfaces.

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Automated Image Analysis Of Nuclear And Cytoplasmic Changes In Exfoliated Cells From Tracheas Treated With Carcinogen

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100078638 ◽

1977 ◽

Vol 35 ◽

pp. 220-221

Author(s):

S.F. Stinson ◽

J.C. Lilga ◽

M.B. Sporn

Keyword(s):

Image Analysis ◽

Pattern Analysis ◽

Relative Proportion ◽

Automated Image Analysis ◽

Image Analyzer ◽

Cross Sectional ◽

Exfoliated Cells ◽

Neoplastic Lesions ◽

Analysis System ◽

Morphologic Criterion

Increased nuclear size, resulting in an increase in the relative proportion of nuclear to cytoplasmic sizes, is an important morphologic criterion for the evaluation of neoplastic and pre-neoplastic cells. This paper describes investigations into the suitability of automated image analysis for quantitating changes in nuclear and cytoplasmic cross-sectional areas in exfoliated cells from tracheas treated with carcinogen.Neoplastic and pre-neoplastic lesions were induced in the tracheas of Syrian hamsters with the carcinogen N-methyl-N-nitrosourea. Cytology samples were collected intra-tracheally with a specially designed catheter (1) and stained by a modified Papanicolaou technique. Three cytology specimens were selected from animals with normal tracheas, 3 from animals with dysplastic changes, and 3 from animals with epidermoid carcinoma. One hundred randomly selected cells on each slide were analyzed with a Bausch and Lomb Pattern Analysis System automated image analyzer.

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Digital Processing of STEM Images

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100097752 ◽

1981 ◽

Vol 39 ◽

pp. 236-237

Author(s):

A. V. Crewe ◽

M. Ohtsuki

Keyword(s):

High Resolution ◽

Low Dose ◽

Assembly Language ◽

Processing System ◽

Principal Component ◽

Digital Processing ◽

Image Analysis System ◽

Black And White ◽

Analysis System ◽

Dose Imaging

We have assembled an image processing system for use with our high resolution STEM for the particular purpose of working with low dose images of biological specimens. The system is quite flexible, however, and can be used for a wide variety of images.The original images are stored on magnetic tape at the microscope using the digitized signals from the detectors. For low dose imaging, these are “first scan” exposures using an automatic montage system. One Nova minicomputer and one tape drive are dedicated to this task.The principal component of the image analysis system is a Lexidata 3400 frame store memory. This memory is arranged in a 640 x 512 x 16 bit configuration. Images are displayed simultaneously on two high resolution monitors, one color and one black and white. Interaction with the memory is obtained using a Nova 4 (32K) computer and a trackball and switch unit provided by Lexidata.The language used is BASIC and uses a variety of assembly language Calls, some provided by Lexidata, but the majority written by students (D. Kopf and N. Townes).

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Chemical Classification and Particle Sizing of Foundry Sands

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118813 ◽

1985 ◽

Vol 43 ◽

pp. 388-389

Author(s):

D.S. DeMiglio

Keyword(s):

Image Analysis ◽

Energy Dispersive Spectrometer ◽

Image Analysis System ◽

Representative Sampling ◽

Foundry Sands ◽

Large Atomic Number ◽

Backscattered Electron ◽

Sand Particles ◽

Analysis System ◽

Reclamation System

Much progress has been made in recent years towards the development of closed-loop foundry sand reclamation systems. However, virtually all work to date has determined the effectiveness of these systems to remove surface clay and metal oxide scales by a qualitative inspection of a representative sampling of sand particles. In this investigation, particles from a series of foundry sands were sized and chemically classified by a Lemont image analysis system (which was interfaced with an SEM and an X-ray energy dispersive spectrometer) in order to statistically document the effectiveness of a reclamation system developed by The Pangborn Company - a subsidiary of SOHIO.The following samples were submitted: unreclaimed sand; calcined sand; calcined & mechanically scrubbed sand and unused sand. Prior to analysis, each sample was sprinkled onto a carbon mount and coated with an evaporated film of carbon. A backscattered electron photomicrograph of a field of scale-covered particles is shown in Figure 1. Due to a large atomic number difference between sand particles and the carbon mount, the backscattered electron signal was used for image analysis since it had a uniform contrast over the shape of each particle.

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Automated high-resolution microscopy: the approaches so far

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100125312 ◽

1987 ◽

Vol 45 ◽

pp. 58-61

Author(s):

W. O. Saxton

Keyword(s):

High Resolution ◽

Early Stage ◽

Automatic Recording ◽

Microprocessor Control ◽

Alternative Systems ◽

Electron Image ◽

Complete Automation ◽

Analysis System ◽

High Resolution Microscopy

Recent commercial microscopes with internal microprocessor control of all major functions have already demonstrated some of the benefits anticipated from such systems, such as continuous magnification, rotation-free diffraction and magnification, automatic recording of mutually registered focal series, and fewer control knobs. Complete automation of the focusing, stigmating and alignment of a high resolution microscope, allowing focal series to be recorded at preselected focus values as well, is still imminent rather than accomplished, however; some kind of image pick-up and analysis system, fed with the electron image via a TV camera, is clearly essential for this, but several alternative systems and algorithms are still being explored. This paper reviews the options critically in turn, and stresses the need to consider alignment and focusing at an early stage, and not merely as an optional extension to a basic proposal.

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HREM observations of internetallic alloy formation in Pt-Sn thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100120667 ◽

1992 ◽

Vol 50 (1) ◽

pp. 52-53

Author(s):

D.C. Dufner

Keyword(s):

Thin Films ◽

Cross Sections ◽

Carbon Films ◽

Solid State Reactions ◽

Alloy Formation ◽

Reaction Behavior ◽

Interdiffusion Process ◽

Compositional Changes ◽

General Goal ◽

Film Method

The general goal of this research is to clarify mechanisms of solid state reactions at the atomic level as a step in the rationalization of macroscopic reaction behavior in solids. A study of intermetallic alloy formation resulting from interdiffusion of metals in thin films can be made by HREM. In this work, reactions between Pt and Sn in thin films are studied to elucidate mechanisms for structural and compositional changes during the interdiffusion process.Thin films of Pt and Sn used in this study were prepared by the two-film method introduced by Shiojiri. Few hundred angstroms of Pt were vacuum-deposited onto holey carbon films mounted on TEM grids. Sn films with an average thickness of 200Å were created by evaporation at rates of 15-30 Å/sec onto air-cleaved KBr substrates. The Sn films were wet-stripped and collected on the holey Pt grids. Figure 1 shows a cross-section schematic of a Pt-Sn couple. While this two-film arrangement did not allow observations of the actual reaction interface, microtomy was used to produce cross-sections.

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Nucleation and initial growth of Pd2Si crystals on Si(111)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100150058 ◽

1993 ◽

Vol 51 ◽

pp. 844-845

Author(s):

Xianghong Tong ◽

Oliver Pohland ◽

J. Murray Gibson

Keyword(s):

High Vacuum ◽

Dark Field ◽

Ultra High Vacuum ◽

Initial Growth ◽

Surface And Interface ◽

Dark Field Imaging ◽

Transmission Electron ◽

Initial Stage ◽

Effect Of Surface

The nucleation and initial stage of Pd2Si crystals on Si(111) surface is studied in situ using an Ultra-High Vacuum (UHV) Transmission Electron Microscope (TEM). A modified JEOL 200CX TEM is used for the study. The Si(111) sample is prepared by chemical thinning and is cleaned inside the UHV chamber with base pressure of 1x10−9 τ. A Pd film of 20 Å thick is deposited on to the Si(111) sample in situ using a built-in mini evaporator. This room temperature deposited Pd film is thermally annealed subsequently to form Pd2Si crystals. Surface sensitive dark field imaging is used for the study to reveal the effect of surface and interface steps.The initial growth of the Pd2Si has three stages: nucleation, growth of the nuclei and coalescence of the nuclei. Our experiments shows that the nucleation of the Pd2Si crystal occurs randomly and almost instantaneously on the terraces upon thermal annealing or electron irradiation.

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