Use of digital microscopy in process control during the manufacture of rubber-modified thermoplastics

Author(s):  
M. T. Dineen

The production of rubber modified thermoplastics can exceed rates of 30,000 pounds per hour. If a production plant needs to equilibrate or has an upset, that means operating costs and lost revenue. Results of transmission electron microscopy (TEM) can be used for process adjustments to minimize product loss. Conventional TEM, however, is not a rapid turnaround technique. The TEM process was examined, and it was determined that 50% of the time it took to complete a polymer sample was related to film processing, even when using automated equipment. By replacing the conventional film portion of the process with a commercially available system to digitally acquire the TEM image, a production plant can have the same TEM image in the control room within 1.5 hours of sampling.A Hitachi H-600 TEM Operated at 100 kV with a tungsten filament was retrofitted with a SEMICAPS™ image collection and processing workstation and a KODAK MEGAPLUS™ charged coupled device (CCD) camera (Fig. 1). Media Cybernetics Image-Pro Plus software was included, and connections to a Phaser II SDX printer and the network were made. Network printers and other PC and Mac software (e.g. NIH Image) were available. By using digital acquisition and processing, the time it takes to produce a hard copy of a digital image is greatly reduced compared to the time it takes to process film.

Author(s):  
R.P. Goehner ◽  
W.T. Hatfield ◽  
Prakash Rao

Computer programs are now available in various laboratories for the indexing and simulation of transmission electron diffraction patterns. Although these programs address themselves to the solution of various aspects of the indexing and simulation process, the ultimate goal is to perform real time diffraction pattern analysis directly off of the imaging screen of the transmission electron microscope. The program to be described in this paper represents one step prior to real time analysis. It involves the combination of two programs, described in an earlier paper(l), into a single program for use on an interactive basis with a minicomputer. In our case, the minicomputer is an INTERDATA 70 equipped with a Tektronix 4010-1 graphical display terminal and hard copy unit.A simplified flow diagram of the combined program, written in Fortran IV, is shown in Figure 1. It consists of two programs INDEX and TEDP which index and simulate electron diffraction patterns respectively. The user has the option of choosing either the indexing or simulating aspects of the combined program.


Author(s):  
Weiping Liu ◽  
Jennifer Fung ◽  
W.J. de Ruijter ◽  
Hans Chen ◽  
John W. Sedat ◽  
...  

Electron tomography is a technique where many projections of an object are collected from the transmission electron microscope (TEM), and are then used to reconstruct the object in its entirety, allowing internal structure to be viewed. As vital as is the 3-D structural information and with no other 3-D imaging technique to compete in its resolution range, electron tomography of amorphous structures has been exercised only sporadically over the last ten years. Its general lack of popularity can be attributed to the tediousness of the entire process starting from the data collection, image processing for reconstruction, and extending to the 3-D image analysis. We have been investing effort to automate all aspects of electron tomography. Our systems of data collection and tomographic image processing will be briefly described.To date, we have developed a second generation automated data collection system based on an SGI workstation (Fig. 1) (The previous version used a micro VAX). The computer takes full control of the microscope operations with its graphical menu driven environment. This is made possible by the direct digital recording of images using the CCD camera.


Author(s):  
F. Hosokawa ◽  
Y. Kondo ◽  
T. Honda ◽  
Y. Ishida ◽  
M. Kersker

High-resolution transmission electron microscopy must attain utmost accuracy in the alignment of incident beam direction and in astigmatism correction, and that, in the shortest possible time. As a method to eliminate this troublesome work, an automatic alignment system using the Slow-Scan CCD camera has been introduced recently. In this method, diffractograms of amorphous images are calculated and analyzed to detect misalignment and astigmatism automatically. In the present study, we also examined diffractogram analysis using a personal computer and digitized TV images, and found that TV images provided enough quality for the on-line alignment procedure of high-resolution work in TEM. Fig. 1 shows a block diagram of our system. The averaged image is digitized by a TV board and is transported to a computer memory, then a diffractogram is calculated using an FFT board, and the feedback parameters which are determined by diffractogram analysis are sent to the microscope(JEM- 2010) through the RS232C interface. The on-line correction system has the following three modes.


2020 ◽  
Vol 29 ◽  
pp. 2633366X2090616
Author(s):  
Ricardo Andrés Solano Pizarro ◽  
Adriana Patricia Herrera Barros

In this research, the photocatalytic degradation of cypermethrin using iron-titanium dioxide (Fe-TiO2) nanoparticles supported in a biomaterial was evaluated. The nanoparticles of TiO2 were synthesized by the green chemistry method assisted by ultrasound and doped by chemical impregnation using Fe+3:Ti molar ratios of 0, 0.05, 0.075 and 0.1 to make efficient use of direct sunlight ( λ > 310 nm). All nanoparticles were immobilized on the surface of coconut spathe ( Cocos nucifera). The degradation was carried out at room temperature and natural pH in a flat plate solar reactor, on which the composite material was subjected. The concentration of cypermethrin was determined after 12,000 J m−2 of accumulated radiation from gas chromatography–mass spectrometry and the resulting material was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, ultraviolet–visible diffuse reflectance spectroscopy, and Brunauer-Emmett-Teller (BET) surface area. The best results were achieved with the use of Evonik TiO2 P-25, Fe:Ti = 0 and Fe:Ti = 0.05 in suspension, with percentages of degradation of cypermethrin of 99.84%, 99.62%, and 100%, respectively. However, the materials supported on the biomaterial of coconut allowed to reach degradation percentages higher than 80%, with the advantage that it minimizes operating costs, as they are not necessarily filtering or centrifuging processes to separate the catalyst.


2000 ◽  
Vol 6 (S2) ◽  
pp. 216-217
Author(s):  
Y. Ikematsu ◽  
D. Shindo ◽  
T. Oikawa ◽  
M. Kersker

Elemental microanalysis has been important in materials characterization, since the elemental distribution strongly affects the property of various materials. A recently developed post-column energy filter coupled with a slow scan CCD camera makes it possible to carry out elemental mapping with a transmission electron microscope. Here, we develop the elemental mapping technique utilizing the omega filter and imaging plates (3760x3000 pixels). Since the data obtained from the imaging plates consist of a large number of pixels, fine and detailed elemental analysis will be expected.Energy-filtered images were obtained by a JEM-2010 electron microscope installed with an omega-type energy filter, and they were recorded on imaging plates (FDL-UR-V:25 μm/pixel). The width of an energy-selecting slit was set to be 20 eV. Elemental maps were obtained from the energy-filtered images using the three window technique. Special care was taken to reduce the image shifts among the three filtered images used in the three-window method.


1999 ◽  
Vol 5 (S2) ◽  
pp. 348-349
Author(s):  
J. Pulokas ◽  
C. Green ◽  
N. Kisseberth ◽  
C.S. Potter ◽  
B. Carragher

We have developed a system (1) for automatically acquiring large numbers of high quality transmission electron micrographs under low dose conditions. This system has been implemented on a Philips CM200 Transmission Electron Microscope equipped with a Gatan MSC CCD camera. Implementing the automated data acquisition system requires that target locations be identified in a low magnification image and then accurately located at the center of the viewing area. The magnification is subsequently increased, the image is focused on an area adjacent to the target area and the final image is acquired. Centering an identified target location for subsequent high magnification imaging typically requires moving the specimen by many thousands of nm and accurately locating the target to within a few hundred nm. This movement is too large to be achieved using the image shift coils, which would be very accurate, and instead must be achieved using the goniometer.We have measured the accuracy of the goniometer on the Philips CM200 and the results are shown in fig 1. Data were obtained by selecting a target area from a low magnification image [660x], moving to this target and then measuring the accuracy of the requested movement by cross correlation.


2000 ◽  
Vol 6 (S2) ◽  
pp. 288-289
Author(s):  
J. Pulokas ◽  
N. Kisseberth ◽  
C.S. Potter ◽  
B. Carragher

For several years we have been developing a software application, called Leginon, for the automated control and acquisition of images from a transmission electron microscope. The system has been developed around a Philips CM200 and a Gatan MSC CCD camera. One of the primary motivations in developing this software is to provide for a system that can acquire many hundreds of images under low dose conditions from a specimen embedded in vitreous ice. In order to set up and manage this system we have developed a number of simple interactive graphical tools that enable the user to design, oversee and manage protocols for controlling the microscope and collecting the images. Many of these simple tools have also proved generally useful as stand alone applications.


2019 ◽  
Vol 50 (3) ◽  
pp. 127-133 ◽  
Author(s):  
Ester Scotto di Perta ◽  
Elena Cervelli ◽  
Maria Pironti di Campagna ◽  
Stefania Pindozzi

Anaerobic digestion (AD) is a mature technology commonly used for manure treatment, both for the stabilisation of waste and for the production of energy. The introduction of new incentives could represent an opportunity for biogas production, when the current feed-in-tariffs, which improved the financial feasibility of AD plants producing electricity will end. This paper examines the feasibility of reconverting an existing AD biogas production plant into a biomethane production plant. The AD plant, in this case study, is a two-stage reactor situated in the centre of Italy and mainly fed with livestock manure from both cows and buffaloes. The economic analysis of two hypotheses is provided: i) continuing the electricity production from biogas after the end of the current incentives (2025); ii) considering the new incentives program for the biomethane and reconverting the plant, using hollow-fibre membranes for the purification of the raw biogas (SEPURAN® Green modules, EnviTec). For this purpose, investment and operating costs, based on plant monitoring data (2105.3 m3 d–1, Biogas production; 4432.9 kWh d–1, electricity production) as well as on market analysis for costs evaluation were considered. The mean biogas production for the considered year was about 30% less than the expected production, indicated by producer, highlighting the need for the optimisation of the management of the reactors. Moreover, based on the averaged methane production (June 2017-June 2018), results show that: i) plant conversion for the biomethane production is not suitable for small-scale plants, due to the high investment costs of upgrading technology (1.2 M€); ii) when current incentives end, the electricity production from biogas in the current plant may not be self-sufficient, due to the highly expensive operating costs. This paper provides a first analysis of the possible fate of the biogas plants under the new incentives.


2001 ◽  
Vol 7 (S2) ◽  
pp. 574-575
Author(s):  
Bernhard Frost ◽  
David C Joy

Even though all real objects are three dimensional, imaging and metrology performed by using electron-beam tools such as scanning electron microscopes is inherently two dimensional. Any information about the third dimension must therefore be obtained by inference, or by time consuming special methods such as stereo-photogrammetry. If, however, the structures of interest are thin enough to be electron transparent then quantitative three dimensional metrology can be performed directly by using off-axis transmission electron holography. Here we demonstrate the application to a SCALPEL lithography mask which consists of chromium lines on a silicon support film. The off-axis holography was performed in a field emission transmission electron microscope, a Hitachi HF2000 operated at 200keV. The sample is positioned so that half the beam passes through the specimen while the rest travels only through the vacuum. An electrostatic biprism then recombines these two components to form the hologram which is recorded onto a CCD camera.


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