Design of Column Separation Processes for Recovery of Molybdenum from Dissolved High-Density LEU Target

AbstractHVPE grown layers typically show a high density of pyramidal structures on the surface. We found that a slight off-orientation of the substrate totally suppresses the development of these structures. Further we found that a misorientation toward the m-plane of GaN features a smoother surface morphology, compared to an off-orientation towards the a-plane. After the improvement of the surface morphology and other properties of the HVPE grown layers, we studied self-separation processes. Our approaches to remove the thick GaN-layer from the substrate were a low-temperature interlayer and a structured dielectric mask.

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Analysis of Triboelectrostatic Separation Process of Mixed Poly(ethylene terephthalate) and High-Density Polyethylene

Energies ◽

10.3390/en15010019 ◽

2021 ◽

Vol 15 (1) ◽

pp. 19

Author(s):

Wieslaw Lyskawinski ◽

Mariusz Baranski ◽

Cezary Jedryczka ◽

Jacek Mikolajewicz ◽

Roman Regulski ◽

...

Keyword(s):

Process Parameters ◽

High Density Polyethylene ◽

Ethylene Terephthalate ◽

Vision System ◽

Separation Process ◽

High Density ◽

Separation Processes ◽

Poly Ethylene Terephthalate ◽

Poly Ethylene

The aim of this study was to investigate and analyze the separation process of poly (ethylene terephthalate) and high-density polyethylene mixture. The research studied the influence of parameters of tribocharging and separation processes on the quality of separation. The research was carried out using a developed test stand consisting of a test tribocharger and a dedicated drum-type electrostatic separator. Both the separator and the tribocharger have been designed as automated test benches to assess the quality of plastic separation. In order to assess the quality of electrostatic separation of plastics, an original method based on the use of a dedicated vision system was used. The research was conducted in two stages. Firstly, the influence of the tribocharging process parameters on the efficiency of the process, i.e., the charge collected, was investigated. The next stage of the research was focused on the analysis of the influence of the separation process parameters on its effectiveness. The obtained results were presented and discussed. On the basis of the conducted research, the parameters of the tribocharging and separation processes affecting their effectiveness were determined.

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Planar defects in ordered (Ga,In)P

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100106570 ◽

1988 ◽

Vol 46 ◽

pp. 902-903

Author(s):

S. McKernan ◽

C. B. Carter ◽

D. Bour ◽

J. R. Shealy

Keyword(s):

Electron Diffraction ◽

Vapor Phase ◽

Growth Direction ◽

High Density ◽

Ordered Structure ◽

Planar Defects ◽

Diffraction Patterns ◽

Ternary Semiconductors ◽

Anion Species ◽

Metallic Vapor

The growth of ternary III-V semiconductors by organo-metallic vapor phase epitaxy (OMVPE) is widely practiced. It has been generally assumed that the resulting structure is the same as that of the corresponding binary semiconductors, but with the two different cation or anion species randomly distributed on their appropriate sublattice sites. Recently several different ternary semiconductors including AlxGa1-xAs, Gaxln-1-xAs and Gaxln1-xP1-6 have been observed in ordered states. A common feature of these ordered compounds is that they contain a relatively high density of defects. This is evident in electron diffraction patterns from these materials where streaks, which are typically parallel to the growth direction, are associated with the extra reflections arising from the ordering. However, where the (Ga,ln)P epilayer is reasonably well ordered the streaking is extremely faint, and the intensity of the ordered spot at 1/2(111) is much greater than that at 1/2(111). In these cases it is possible to image relatively clearly many of the defects found in the ordered structure.

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Quantitative defect studies in semiconductor TEM samples prepared by low angle ion milling

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138932 ◽

1995 ◽

Vol 53 ◽

pp. 512-513

Author(s):

L. Mulestagno ◽

J.C. Holzer ◽

P. Fraundorf

Keyword(s):

Sample Preparation ◽

Milling Time ◽

High Density ◽

Low Density ◽

Ion Milling ◽

High Quality ◽

Variable Angle ◽

Major Disadvantage ◽

Induced Defects

Due to the wealth of information, both analytical and structural that can be obtained from it TEM always has been a favorite tool for the analysis of process-induced defects in semiconductor wafers. The only major disadvantage has always been, that the volume under study in the TEM is relatively small, making it difficult to locate low density defects, and sample preparation is a somewhat lengthy procedure. This problem has been somewhat alleviated by the availability of efficient low angle milling.Using a PIPS® variable angle ion -mill, manufactured by Gatan, we have been consistently obtaining planar specimens with a high quality thin area in excess of 5 × 104 μm2 in about half an hour (milling time), which has made it possible to locate defects at lower densities, or, for defects of relatively high density, obtain information which is statistically more significant (table 1).

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A SEM/TEM examination of a ceramic membrane

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100144802 ◽

1986 ◽

Vol 44 ◽

pp. 682-683

Author(s):

C.E. Voegele-Kliewer ◽

A.D. McMaster ◽

G.W. Dirks

Keyword(s):

Electron Microscopy ◽

Gas Separation ◽

Ceramic Membrane ◽

Hydrogen Iodide ◽

Separation Processes ◽

Corning Glass ◽

Gas Transport Properties ◽

Porous Microstructure ◽

Microscopy Techniques ◽

The Relationship

Materials other than polymers, e.g. ceramic silicates, are currently being investigated for gas separation processes. The permeation characteristics of one such material, Vycor (Corning Glass #1370), have been reported for the separation of hydrogen from hydrogen iodide. This paper will describe the electron microscopy techniques applied to reveal the porous microstructure of a Vycor membrane. The application of these techniques has led to an increased understanding in the relationship between the substructure and the gas transport properties of this material.

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Using the scanning electron microscope for failure analysis of high density magnetic media

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126755 ◽

1987 ◽

Vol 45 ◽

pp. 392-393

Author(s):

Evelyn R. Ackerman ◽

Gary D. Burnett

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Failure Analysis ◽

High Density ◽

Magnetic Media ◽

Specific Data ◽

Retrieval Systems ◽

Operating Environments ◽

The Media ◽

Scanning Electron

Advancements in state of the art high density Head/Disk retrieval systems has increased the demand for sophisticated failure analysis methods. From 1968 to 1974 the emphasis was on the number of tracks per inch. (TPI) ranging from 100 to 400 as summarized in Table 1. This emphasis shifted with the increase in densities to include the number of bits per inch (BPI). A bit is formed by magnetizing the Fe203 particles of the media in one direction and allowing magnetic heads to recognize specific data patterns. From 1977 to 1986 the tracks per inch increased from 470 to 1400 corresponding to an increase from 6300 to 10,800 bits per inch respectively. Due to the reduction in the bit and track sizes, build and operating environments of systems have become critical factors in media reliability.Using the Ferrofluid pattern developing technique, the scanning electron microscope can be a valuable diagnostic tool in the examination of failure sites on disks.

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