Dose imaging with gel-dosemeter layers: optical analysis and dedicated software

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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Computer averaging of lattice images of poly-4-methyl-pentene-1 (P4mp1): Noise created artifacts

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126731 ◽

1987 ◽

Vol 45 ◽

pp. 388-389

Author(s):

P. Pradère ◽

J.F. Revol ◽

R. St. John Manley

Keyword(s):

Low Dose ◽

Polymer Concentration ◽

Processing System ◽

Limiting Factor ◽

Dilute Solution ◽

New Techniques ◽

Dose Unit ◽

Lattice Images ◽

Dose Imaging ◽

Imaging Conditions

Although radiation damage is the limiting factor in HREM of polymers, new techniques based on low dose imaging at low magnification have permitted lattice images to be obtained from very radiation sensitive polymers such as polyethylene (PE). This paper describes the computer averaging of P4MP1 lattice images. P4MP1 is even more sensitive than PE (total end point dose of 27 C m-2 as compared to 100 C m-2 for PE at 120 kV). It does, however, have the advantage of forming flat crystals from dilute solution and no change in d-spacings is observed during irradiation.Crystals of P4MP1 were grown at 60°C in xylene (polymer concentration 0.05%). Electron microscopy was performed with a Philips EM 400 T microscope equipped with a Low Dose Unit and operated at 120 kV. Imaging conditions were the same as already described elsewhere. Enlarged micrographs were digitized and processed with the Spider image processing system.

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Quantitative nano-characterization of heterogeneous catalysts

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138361 ◽

1995 ◽

Vol 53 ◽

pp. 398-399

Author(s):

P.A. Crozier ◽

M. Pan

Keyword(s):

Heterogeneous Catalysts ◽

Low Dose ◽

Imaging Techniques ◽

Structural Features ◽

Catalyst Characterization ◽

New Developments ◽

Double Phase ◽

Phase Systems ◽

Dose Imaging

Heterogeneous catalysts can be of varying complexity ranging from single or double phase systems to complicated mixtures of metals and oxides with additives to help promote chemical reactions, extend the life of the catalysts, prevent poisoning etc. Although catalysis occurs on the surface of most systems, detailed descriptions of the microstructure and chemistry of catalysts can be helpful for developing an understanding of the mechanism by which a catalyst facilitates a reaction. Recent years have seen continued development and improvement of various TEM, STEM and AEM techniques for yielding information on the structure and chemistry of catalysts on the nanometer scale. Here we review some quantitative approaches to catalyst characterization that have resulted from new developments in instrumentation.HREM has been used to examine structural features of catalysts often by employing profile imaging techniques to study atomic details on the surface. Digital recording techniques employing slow-scan CCD cameras have facilitated the use of low-dose imaging in zeolite structure analysis and electron crystallography. Fig. la shows a low-dose image from SSZ-33 zeolite revealing the presence of a stacking fault.

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Optical analysis of ink and other contaminants in process waters

TAPPI Journal ◽

10.32964/tj11.8.51 ◽

2012 ◽

Vol 11 (8) ◽

pp. 51-58

Author(s):

ANTTI HAAPALA ◽

MIKA KÖRKKÖ ◽

ELISA KOIVURANTA ◽

JOUKO NIINIMÄKI

Keyword(s):

Optically Active ◽

Process Water ◽

Paper Machine ◽

Optical Analysis ◽

Direct Process ◽

Active Components ◽

Water Contaminants ◽

Dependent Measurement ◽

Measurement Methodology

Analysis methods developed specifically to determine the presence of ink and other optically active components in paper machine white waters or other process effluents are not available. It is generally more interest¬ing to quantify the effect of circulation water contaminants on end products. This study compares optical techniques to quantify the dirt in process water by two methods for test media preparation and measurement: direct process water filtration on a membrane foil and low-grammage sheet formation. The results show that ink content values obtained from various analyses cannot be directly compared because of fundamental issues involving test media preparation and the varied methodologies used to formulate the results, which may be based on different sets of assumptions. The use of brightness, luminosity, and reflectance and the role of scattering measurements as a part of ink content analysis are discussed, along with fine materials retention and measurement media selection. The study concludes with practical tips for case-dependent measurement methodology selection.

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In Vivo Optical Analysis of Quantitative Changes in Collagen and Elastin During Arterial Remodeling¶

Photochemistry and Photobiology ◽

10.1562/2004-03-10-ra-107.1 ◽

2005 ◽

Vol 81 (2) ◽

pp. 457 ◽

Cited By ~ 19

Author(s):

Alexander Christov ◽

Renee M. Korol ◽

Erbin Dai ◽

Liying Liu ◽

Haiyan Guan ◽

...

Keyword(s):

Arterial Remodeling ◽

Optical Analysis ◽

Quantitative Changes

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Aero-optical analysis of compressible flow over an open cavity

10.2514/6.1987-1399 ◽

1987 ◽

Author(s):

PHILIP CASSADY ◽

STANLEY BIRCH ◽

P. TERRY

Keyword(s):

Compressible Flow ◽

Open Cavity ◽

Optical Analysis

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VLSI for Space Applications—Single Event Effect Investigation and Optical Analysis on an Integrated Laser Platform

ISTFA 2017: Conference Proceedings from the 43rd International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2017p0621 ◽

2017 ◽

Author(s):

Samuel Chef ◽

Chung Tah Chua ◽

Yu Wen Siah ◽

Philippe Perdu ◽

Chee Lip Gan ◽

...

Keyword(s):

Pulsed Laser ◽

Single Event ◽

Optical Analysis ◽

Space Applications ◽

Laser Probing ◽

Single Event Effect ◽

Evaluation Time ◽

Black Boxes ◽

System Use ◽

First Time

Abstract Today’s VLSI devices are neither designed nor manufactured for space applications in which single event effects (SEE) issues are common. In addition, very little information about the internal schematic and usually nothing about the layout or netlist is available. Thus, they are practically black boxes for satellite manufacturers. On the other hand, such devices are crucial in driving the performance of spacecraft, especially smaller satellites. The only way to efficiently manage SEE in VLSI devices is to localize sensitive areas of the die, analyze the regions of interest, study potential mitigation techniques, and evaluate their efficiency. For the first time, all these activities can be performed using the same tool with a single test setup that enables a very efficient iterative process that reduce the evaluation time from months to days. In this paper, we will present the integration of a pulsed laser for SEE study into a laser probing, laser stimulation, and emission microscope system. Use of this system will be demonstrated on a commercial 8 bit microcontroller.

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