Welding of very thin foil.
Electron beam welding method for very thin foils, discussing welding of pinhole free Ni, Cu and stainless steel foils
Fowler, P.↗
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Electrical reliability of parylene films for device passivation
High purity pinhole free films /parylene/ applicability as barrier coating to keep semiconductor surface free from moisture, ions and contaminants
Lee, S. M.↗
Compact spectroradiometer
Development and characteristics of spectroradiometer with wedge filters to eliminate adverse effect of pinholes in filters
Seward, H. H.↗
Advantages of vapor-plated phosphosilicate films in large-scale integrated circuit arrays
MOS large scale IC phosphosilicate glass substrate vapor deposits effects, including hardness, pinhole density and electromigration
Keen, R. S., Jr.↗
Sputtering: A vacuum deposition method for coating material
The sputtering process is described in terms of its features: versatility, momentum transfer, configuration of target, precise controls and the relatively slow deposition rate. Sputtered films are evaluated in terms of adherence, coherence, and internal stresses. The strong adherence is attributed to the high kinetic energies of the sputtered material, sputter etched (cleaned) surface, and the submicroscopic particle size. An illustration is a sputtered solid film lubricant such as MoS2. Friction tests were conducted on a thin, 2000 A deg thick MoS2 film. These films are very dense and without observable pinholes, and the particle to particle cohesion is strong. Tolerances (film thickness) can be controlled to a millionth of a centimeter. Very adherent films of sputtered Teflon can be deposited in a single operation on any type of material (metal, glass, paper) and on any geometrical configuration with a dense adherent film.
Spalvins, T.↗
Lubrication with sputtered MoS2 films.
Sputtered MoS2 films (2000-6500 A) were deposited on highly polished metal surfaces. These films have a low coefficient of friction (0.03-0.04) at speeds of 40-80 rpm and loads of 250-1000 grams. At loads of 250 grams the wear lives are over 0.5 million cycles, but at 1000 gram loads, it decreases to 38,000 cycles. Friction experiments and tensile tests have indicated that sputtered films have a strong adherence to metal surfaces. Electron transmission, diffraction and scanning electron microscopy show that these films have an extremely small particle size, less than 30 A in diameter, and are very dense and free from observable pinholes. The high kinetic energy of these sputtered species, the submicroscopic particle size and the sputter-etched substrate surface is responsible for strong adhesion and cohesion of the sputtered film.
Spalvins, T.↗
Lubrication with sputtered MoS2 films.
Sputtered MoS2 films (2000-6500 A) were deposited on highly polished metal surfaces. These films have a low coefficient of friction (0.03-0.04) at speeds of 40-80 rpm and loads of 250-1000 grams. At loads of 250 grams, the wear lives are over 0.5 million cycles, but at 1000 gram loads, it decreases to 38,000 cycles. Friction experiments and tensile tests have indicated that sputtered films have a strong adherence to metal surfaces. Electron transmission, diffraction, and scanning electron microscopy show that these films have an extremely small particle size less than 30 A in diameter and are very dense and free from observable pinholes.
Spalvins, T.↗
The reaction of hydrogen peroxide with nitrogen dioxide and nitric oxide.
The reactions were studied with the aid of a mass spectrometer. A pinhole bleed system provided continuous sampling of the gas mixture in the cell during the reaction. It was found that the homogeneous reactions of nitric oxide and nitrogen dioxide with hydrogen peroxide are too slow to be of any significance in the upper atmosphere. However, the heterogeneous reactions may be important in the conversion of nitric oxide to nitrogen dioxide in the case of polluted urban atmospheres.
Gray, D.↗
The reaction of H2O2 with NO2 and NO
The reactions of NO and NO2 with H2O2 have been examined at 25 C. Reaction mixtures were monitored by continuously bleeding through a pinhole into a monopole mass spectrometer. NO2 was also monitored by its optical absorption in the visible part of the spectrum. Reaction mixtures containing initially 1.5 - 2.5 torr of NO2 and 0.8 - 1.4 torr of H2O2 or 1 - 12 torr of NO and 0.5 - 1.5 torr of H2O2 were studied. The H2O2 - NO reaction was complex. There was an induction period followed by a marked acceleration in reactant removal. The final products of the reaction, NO2, probably H2O, and possibly HONO2 were produced mainly after all the H2O2 was removed. The HONO intermediate was shown to disproportionate to NO2 + NO + H2O in a relatively slow first order reaction. The acceleration in H2O2 removal after the NO - H2O2 reaction is started is caused by NO2 catalysis.
Gray, D.↗
High voltage solar array experiments
The interaction between the components of a high voltage solar array and a simulated space plasma is studied to obtain data for the design of a high voltage solar array capable of 15kW at 2 to 16kV. Testing was conducted in a vacuum chamber 1.5-m long by 1.5-m diameter having a plasma source which simulated the plasma conditions existing in earth orbit between 400 nautical miles and synchronous altitude. Test samples included solar array segments pinholes in insulation covering high voltage electrodes, and plain dielectric samples. Quantitative data are presented in the areas of plasma power losses, plasma and high voltage induced damage, and dielectric properties. Limitations of the investigation are described.
Kennerud, K. L.↗
Study of X-ray optics
The testing is reported of a polished Kanigen coated beryllium mirror in a soft X-ray telescope to be flown on a Skylark sounding rocket. This test involved inserting the telescope in a 220 foot long vacuum line and taking photographs of an X-ray resolution source. These photographs were then used to evaluate the performance of the telescope mirror as a function of distance from the focal plane and the angular distance off the telescope axis. A second test was made in which a point source was used to study the imaging characteristics by means of a pinhole and proportional counter placed in the telescope focal plane. A third test was conducted using a position sensitive detector. The efficiency and resolution was increased by polishing.
Froechtenigt, J. F.↗
Experimental investigation of the cornering characteristics of 18 by 5.5, type 7, aircraft tires with different tread patterns
The characteristics, which include the cornering-force and drag-force friction coefficients and self-alining torque, were obtained on dry, damp, and flooded runway surfaces over a range of yaw angles from 0 deg to 12 deg and at ground speeds from approximately 5 to 90 knots. The results indicate that a tread pattern with pinholes in the ribs reduces the tire cornering capability at high yaw angles on a damp surface but improves cornering on a dry surface. A tread pattern which has transverse grooves across the entire width of the tread improves the tire cornering performance slightly at high speeds on the flooded runway surface. The cornering capability of all the tires is degraded at high ground speeds by thin film lubrication and/or tire hydroplaning effects. Alterations to the conventional tread pattern provide only marginal improvements in the tire cornering capability which suggests that runway surface treatments may be a more effective way of improving aircraft ground performance during wet operations.
Dreher, R. C.↗
Physical correction filter for improving the optical quality of an image
A family of physical correction filters is described. Each filter is designed to correct image content of a photographed scene of limited resolution and includes a first filter element with a pinhole through which light passes to a differential amplifier. A second filter element through which light passes through one or more openings, whose geometric configuration is a function of the cause of the resolution loss included. The light, passing through the second filter element, is also supplied to the differential amplifier whose output is used to activate an optical display or recorder to reproduce a photograph or display of the scene in the original photograph or display of the scene in the original photograph with resolution which is significantly greater than that characterizing the original photograph.
Lee, S. Y.↗
The interaction of spacecraft high voltage power systems with the space plasma environment
Research work has shown that the interaction of a spacecraft and its high voltage power systems with the space plasma environment can result in harmful power loss and damage to insulators and metal surfaces. Insulator and solar panel tests were performed and flight tests are planned. High voltage power processing equipment was shown to be affected by power loss, and by transients due to plasma interactions. Power loss was determined to be roughly proportional to the square of the voltage and increases approximately as the square root of the area. Kapton, Teflon, and glass were found to be satisfactory insulating materials and it is concluded that for large space power stations should consider the effect of large pinhole currents.
Domitz, S.↗
Simplified deflection-coil linearity testing
Mask placed over face of image-dissecting photomultiplier tube has precision array of pinholes that permit light to impinge on tube at known points. Signals are fed to deflection coil which sweeps beam across each point without complex operator procedures.
Kramer, G. P.↗
Long-term X-ray studies of Sco X-1
No modulation of the 3-6 keV X-ray intensity of Sco X-1 at a level of excess of 1% was observed at the optical period of .787313d. Evidence is found for shot-noise character in a large fraction of the X-ray emission. Almost all of the Sco X-1 emission can be synthesized in terms of approximately 200 shots per day, each with a duration of approximately 1/3 day. A pinhole camera was used to obtain data and the data were statistically analyzed.
Holt, S. S.↗
Limb brightening on Uranus - The visible spectrum
Results are presented for pinhole and slit narrowband photoelectric area-scanning photometry of the Uranus disk at eight central wavelengths ranging from 5600 to 7500 A. The observations were undertaken to detect limb brightening on the planet and to study the nature of its disk profile as a function of geometrical albedo. A coarse analysis of the results shows that the disk must exhibit limb brightening in the two CH4 bands at 6190 and 7300 A relative to all other wavebands investigated. Except for the two CH4 bands, the shapes and widths of the images are found to be essentially identical; point-spread-function data for all wavebands indicate no significant variation in the representative Gaussian l/e width with wavelength. A fine analysis of the data reveals absolute limb brightening in the 7300-A CH4 band and absolute limb darkening in the adjacent wavebands. These results are shown to be consistent with the hypothesis that clouds are absent from the visible atmosphere of Uranus.
Price, M. J.↗
Testing internal coatings in metal vessels
Presence of pinholes or defects in nonconductive protective coating on inside surface of closed vessel is detected if vessel has one opening into which small stainless-steel probe can be introduced. By inserting probe and attaching another to outside surface, and by filling vessel with ten percent sodium chloride solution, integrity of coating is determined by measuring electrical conductivity through vessel wall.
Ruby, A.↗