Optical Aspherizing by Vacuum Evaporation

Nature ◽  
1955 ◽  
Vol 175 (4458) ◽  
pp. 646-647 ◽  
Author(s):  
J. A. DOBROWOLSKI ◽  
W. WEINSTEIN
Keyword(s):  
Vacuum Evaporation

Quality films from carbon fiber evaporation for thorough coverage of TEM grids

1988 ◽  
Vol 46 ◽  
pp. 418-419
Author(s):  
N. Tempel ◽  
M. C. Ledbetter
Keyword(s):  
Electron Microscopy ◽  
High Resolution Electron Microscopy ◽  
Carbon Films ◽  
Low Noise ◽  
Vacuum Evaporation ◽  
High Yield ◽  
Good Adhesion ◽  
Noise Structure ◽  
Resolution Electron ◽  
Carbon Foils

Carbon films have been a support of choice for high resolution electron microscopy since the introduction of vacuum evaporation of carbon. The desirable qualities of carbon films and methods of producing them has been extensively reviewed. It is difficult to get a high yield of grids by many of these methods, especially if virtually all of the windows must be covered with a tightly bonded, quality film of predictable thickness. We report here a method for producing carbon foils designed to maximize these attributes: 1) coverage of virtually all grid windows, 2) freedom from holes, wrinkles or folds, 3) good adhesion between film and grid, 4) uniformity of film and low noise structure, 5) predictability of film thickness, and 6) reproducibility.Our method utilizes vacuum evaporation of carbon from a fiber onto celloidin film and grid bars, adhesion of the film complex to the grid by carbon-carbon contact, and removal of the celloidin by acetone dissolution. Materials must be of high purity, and cleanliness must be rigorously maintained.

“Preparation of Single Crystalline Gold Films for ED Studies”

1972 ◽  
Vol 30 ◽  
pp. 634-635
Author(s):  
Joseph D. C. Peng
Keyword(s):  
Crystal Morphology ◽  
Diffraction Theory ◽  
Scattering Matrix ◽  
Vacuum Evaporation ◽  
Gold Films ◽  
Matrix Formulation ◽  
Silver Films ◽  
Single Crystalline ◽  
Grating Pattern ◽  
Stacking Disorder

The relative intensities of the ED spots in a cross-grating pattern can be calculated using N-beam electron diffraction theory. The scattering matrix formulation of N-beam ED theory has been previously applied to imperfect microcrystals of gold containing stacking disorder (coherent twinning) in the (111) crystal plane. In the present experiment an effort has been made to grow single-crystalline, defect-free (111) gold films of a uniform and accurately know thickness using vacuum evaporation techniques. These represent stringent conditions to be met experimentally; however, if a meaningful comparison is to be made between theory and experiment, these factors must be carefully controlled. It is well-known that crystal morphology, perfection, and orientation each have pronounced effects on relative intensities in single crystals.The double evaporation method first suggested by Pashley was employed with some modifications. Oriented silver films of a thickness of about 1500Å were first grown by vacuum evaporation on freshly cleaved mica, with the substrate temperature at 285° C during evaporation with the deposition rate at 500-800Å/sec.

scholarly journals Selective Vacuum Evaporation by the Control of the Chemistry of Gas Phase in Vacuum Refining of Si

Langmuir ◽  
2021 ◽  
Author(s):  
Arman Hoseinpur ◽  
Stefan Andersson ◽  
Kai Tang ◽  
Jafar Safarian
Keyword(s):  
Gas Phase ◽  
Vacuum Evaporation ◽  
Vacuum Refining

Production of grape pekmez by Ohmic heating-assisted vacuum evaporation

2021 ◽  
pp. 108201322199161
Author(s):  
Merve Tuçe Tunç ◽  
Arda Akdoğan ◽  
Cemalettin Baltacı ◽  
Zeliha Kaya ◽  
Halil İbrahim Odabaş
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Ohmic Heating ◽  
Vacuum Evaporation ◽  
Voltage Gradient ◽  
Evaporation Process ◽  
Significant Difference ◽  
Total Process ◽  
Energy Consumptions ◽  
Voltage Gradients

Pekmez is a concentrated syrup-like food conventionally produced by vacuum evaporation process from sugar-rich fruits. In this study, the applicability of grape pekmez production by ohmic heating assisted vacuum evaporation (ΩVE) method was investigated. Conventional vacuum evaporation (CVE) and ΩVE methods were compared in terms of physicochemical properties, HMF (5-hydroxymethylfurfural) contents, rheological properties, and energy consumptions. ΩVE was run at four different voltage gradients (17.5, 20, 22.5, and 25 V/cm). Total process times for grape pekmez production were determined as 57, 28.5, 32, 39, and 50 minutes for CVE, ΩVE (25 V/cm), ΩVE (22.5 V/cm), ΩVE (20 V/cm) and ΩVE (17.5 V/cm), respectively. Energy consumption of CVE method was higher than ΩVE method for all voltage gradients. Energy efficiency increased as the voltage gradient increased. There was no significant difference between CVE and ΩVE methods for HMF contents. The results show that the ΩVE method could be an alternative to the CVE process for grape pekmez production.

Effect of post-oxidation processes and thickness of SnO2 films prepared by vacuum evaporation on CO gas sensing characteristics

2021 ◽  
Author(s):  
Amit Kumar Mauraya ◽  
Preetam Singh ◽  
Saravanan Muthiah ◽  
Sunil Singh Kushvaha ◽  
Senthil Kumar Muthusamy
Keyword(s):  
Gas Sensing ◽  
Vacuum Evaporation ◽  
Oxidation Processes ◽  
Sensing Characteristics ◽  
Co Gas

The prevention of scaling by decreasing the concentration of scale-forming ions in the vacuum evaporation salt-making process

2021 ◽  
pp. 119337
Author(s):  
Xingguo Luo ◽  
Xingbin Li ◽  
Chang Wei ◽  
Sanqiang Zheng ◽  
Zhigan Deng ◽  
...  
Keyword(s):  
Vacuum Evaporation

Influence of heat treatment on the microstruture of SnS/ZnS film prepared by vacuum evaporation

2010 ◽  
Author(s):  
Wenjun Wu ◽  
Weimin Shi ◽  
Zhe Hu ◽  
Sheng Liu ◽  
Weiguang Yang ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Vacuum Evaporation
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