WorldCat Identities


Works: 19 works in 26 publications in 1 language and 26 library holdings
Classifications: TK5103.5,
Publication Timeline
Study of thin film compounds formed from simultaneously evaporated constituents( Book )

2 editions published between 1963 and 1964 in English and held by 2 WorldCat member libraries worldwide

Thin films of lead titanate have a number of advantages over barium titanate. Details of the preparation of lead titanate films by the simultaneous evaporation of lead and titanium oxides, initial attempts to increase the electrical resistance by the incorporation of small amounts of metal oxides, and preliminary experiments with insulator substrates are described. The capacitance, dissipation factor and leakage resistance of lead titanate films are comparable to those found for barium titanate. The frequency dependence of the capacitance and losses follows closely a relation given by Gevers for dielectrics of irregular structure. Strong x-ray diffraction patterns of tetragonal PbTiO3 have been obtained for films 1500 to 2500 A thick. Electron micrographs of the film surface show a uniform texture of grains of sizes between 1000 and 3000 A. (Author)
Free carrier microwave semiconductor devices( Book )

2 editions published between 1966 and 1967 in English and held by 2 WorldCat member libraries worldwide

A small signal analysis is presented by the bulk terminal impedance of a CdS bar in which the drifting charge carriers and vibrating lattice interact via the piezoelectric coupling. It was shown through a sample calculation that for practical ranges of applied drift voltage, material parameters, and semiconductor dimensions a negative real part to the terminal impedance could be achieved at room temperatures. The magnitude of this negative real part of the terminal impedance makes possible the design of practical bulk amplifiers and oscillators in 50 ohm TEM mode transmission line. Experiments on low resistivity (semiconducting) CdS indicate that acoustoelectric interaction takes place in the crystal for applied pulse drift electric fields above a threshold field corresponding to the synchronous carrier velocity. Microwave measurements show that rf radiation emanates from the bulk CdS sample and is associated with the acousto-electric interaction. It was observed that radiation occurs both during the period of domain travel in the sample and during the time of domain collapse at the anode. Using optical probe techniques, the spectrum of the acoustic lattice waves in CdS under conditions of high pulsed electric field has been measured. It was determined that the spectrum exhibited a peak amplitude at one frequency and that this frequency was determined by the nature of the acoustic pulse nucleation site. (Author)

2 editions published between 1968 and 1969 in English and held by 2 WorldCat member libraries worldwide

Work is described concerning the design and initial evaluation of Ni-Fe cells in the nickel-cadmium BB616()/U size and Ni-Zn cells in the silver-zinc BB462()/U size. The effect of parameters of cell construction such as electrode thickness, electrode geometry, separator type, electrolyte concentration, and electrolyte additives on the cell output characteristics are being evaluated in factorially designed experiments. Data analysis is being performed by multiple linear regression techniques via computer. Three experiments are described showing the significant effects of variables studies. These experiments indicate that the minimum energy density goals of 12.5 Wh/lb for Ni-Fe and 22 Wh/lb for Ni-Zn (at C/5 and 80F) can be exceeded in these cell sizes. (Author)

2 editions published between 1963 and 1964 in English and held by 2 WorldCat member libraries worldwide

The research on chelate lasers has been organized along two general lines. The first is an investigation of the properties of the materials in terms of the requirements for laser action. The second is a study of the characteristics of the chelate laser itself. The resultant information is essential for a full appreciation of the potential of chelate laser systems. A number of chelates can serve as laser materials, chemically shift the frequency of one chelate laser system by about 60 cm-1 and increase the operating temperature, in one case as high as 300 K. These results indicate that the achievement of room-temperature laser action in a circulating fluid medium is not only practicable but, at this point, awaits only the development on suitable technological services. (Author)
Semiconductor microwave amplitude and phase modulator( Book )

2 editions published between 1963 and 1966 in English and held by 2 WorldCat member libraries worldwide

Research was continued on the development of a semiconductor microwave amplitude and phase modulator that makes use of the interaction of propagating electromagnetic fields with injected carriers in a semiconductor medium for application at a wavelength of 4.28 millimeters. A more flexible modulator configuration was analyzed in which adjustable susceptive irises were added to the semiconductor-loaded waveguide structure previously treated. In this new configuration resonance is no longer dependent solely on the semiconductor length. Numerical computations indicate that the structure with irises can provide somewhat lower insertion loss than that without irises but otherwise exhibits the same essential features. The possibility of realizing modulation bandwidths up to 1 mc was demonstrated in a reduced height test structure. (Author)

2 editions published in 1966 in English and held by 2 WorldCat member libraries worldwide

Hot-carrier effects in semiconductors were applied to the development of microwave devices for operation in the 70-90-GHz range. The program included an investigation of hot-carrier devices, and a study of phonons created in semiconductors by high electric fields. A microwave hot-carrier detector, mixer, modulator and harmonic generator were developed. The hot-carrier detector exhibits a linear detection characteristics for input powers up to 10 mW. Curves of detector sensitivity vs input power are given. The InSb performance characteristics of InSb hot-carrier mixers operated at liquid-nitrogen temperature and Ge and GaAs mixers operated at room temperature are described. Mixer performance is characterized in terms of i.f. resistance, conversion loss, noise-temperature ratio and the sensitivity of an experimental 70-GHz receiver using the mixer as a first stage. The hot-carrier modulator developed is capable of amplitude modulating a 70-90-GHz carrier with a modulation bandwidth of 5 GHz. Modulation indices at 4 MHz were usually above 60 per cent; at 6 GHz between 10 and 20%. Insertion loss was typically less than 6 dB. Third-harmonic generators driven with a pulsed 70-GHz signal was obtained with conversion losses as low as 38 dB. Several harmonic generators withstood peak inputs of 1.6 kW. Attempts were made to observe effects due to phonons in the 100-GHz range generated by heated carriers in germanium at liquid-helium temperatures. The observed effects were more likely due to carrier diffusion and heat pulses than to phonons in the desired range
Conference on organic lasers, at the general telephone + electronics laborattories inc( Book )

1 edition published in 1964 in English and held by 1 WorldCat member library worldwide

Investigation of the chemical reaction between tungsten and aluminum oxide( Book )

1 edition published in 1960 in English and held by 1 WorldCat member library worldwide

Studies of electron tube materials and thermionic emission processes( Book )

1 edition published in 1960 in English and held by 1 WorldCat member library worldwide


1 edition published in 1960 in English and held by 1 WorldCat member library worldwide

Identification of microstructural constituents and chemical concentration profiles in coated refractory metal systems by D. J Bracco( Book )

1 edition published in 1966 in English and held by 1 WorldCat member library worldwide

Coated refractory metal systems exposed to high temperatures at atmospheric pressure and at low pressures were surveyed to reveal resultant microstructure and chemical concentration profiles for interpretation of coating behavior under high-temperature oxidizing conditions. Identification of the constituents of coatings and substrates before and after oxidation is carried out mainly by electron probe techniques supplemented by x-ray diffraction. Representative substrates chosen for study include the pure metals and alloys based on Cb, Mo, Ta and W. The coatings include a selection of commercially available materials ranging from pure silicides to silicides modified with with one to three additives in trace and bulk amounts. (Author)
Study of nonlinear effects on semiconductive materials( Book )

1 edition published in 1960 in English and held by 1 WorldCat member library worldwide

A solid-state self-scanning display device. Prepared for: Rome Air Development Center, Air Force Systems Command, U.S. Air Force by M. S Wasserman( )

1 edition published in 1962 in English and held by 0 WorldCat member libraries worldwide

Investigation is described of materials for use in a solid-state electroluminescent display de vice in which the electric field for activation of the electroluminescent layer is provided by elastic waves, propagated through a piezoelectric ceramic plating as the substrate for dis play. The first phase was devoted to a search for improved piezoelectic ceramics. In the sec ond phase of the investigation, emphasis was placed on an investigation of the problems asso ciated with integration of the piezoelectric, nonlinear resistive and electroluminescent mate rials into complete display structures. Bright ness and resolution of the display are limited by the fact that the electroluminescent layer ex hibits a nonlinear resistive characteristic at high field strength. The expected effect of im proved propagation characteristics of hot-pressed ceramics has also been assessed. Finally, it has been shown that a significant increase in bright ness can be achieved if the display design is revised. Its output pulses would be used to gate power from an independent source
Hot carrier phenomena in semiconductors at microwave frequencies( )

1 edition published in 1962 in English and held by 0 WorldCat member libraries worldwide

An expression is derived for the diffusion constant D(i) of thermal carriers in the ith valley of a many-valley semiconductor. In n-Ge, intervalley scattering is sufficiently rapid so that the actual diffusion rate depends on the average of the diffusion constant over the valleys, which is a scalar. The same result is obtained for the diffusion constant when a high electric field is applied perpendicular to the concentration gradient, except that the average must be taken over the actual energy distribution of carriers in the high field. At 3 kmc the time variation of the field is slow enough so that the instantaneous D should be equal to D for a dc field of the same magnitude. For measurements of recombination in high electric fields the method of injection was changed from surface illumination to point-contact injection. Data on recombination, conductivity and dielectric constant were obtained for high-frequency fields. Some anomalies are mentioned
Experimental study of factors controlling the effectiveness of high-temperature protective coatings for tungsten by C. D Dickinson( )

1 edition published in 1962 in English and held by 0 WorldCat member libraries worldwide

Two processes governing the efficacy of high temperature protective coatings for tungsten, interdiffusion in ternary oxygen-metal-metal systems and breakaway during oxide film growth, are being investigated experimentally to deter mine the oxidation behavior of binary alloys and the influence of substrate mechanical properties on the growth characteristics of the films. Experiments involving oxidation kinetics and the microstructural and quantitative identification of the layers formed have been conducted on four systems. An analysis of the diffusion processes governing growth in the Zr-Th- O system is pre sented, and a preliminary discussion of the re sults obtained in the W-Hf-O, ZrN-ThN-O and Sn Al-Cr systems is given
Thin films formed by electrochemical reactions( )

1 edition published in 1963 in English and held by 0 WorldCat member libraries worldwide

The technique of forming thin-film capacitors by the anodic oxidation of the surfaces of vacuum deposited films of aluminum, tantalum, tungsten, titanium and zirconium has been investigated. Breakdown voltages equal to or greater than the anodization forming voltage have been obtained, resulting in a usable capacitance voltage product of 13.5 microfarad v/sq cm. The uniformity of capacitance measured for a large number of test samples fell within a standard deviation of 3 percent. Electrical properties over a range of frequency and tempera ture have been evaluated. The preparation of thin-film resistors by forming vacuum-deposited metal in a predetermined pattern and then partially anodizing the deposited metal to a precise resistance has been studied for tantalum and tungsten. The properties of vacuum-deposited films of titanium and zirconium that are related to their use as resistors has also been investigated
Oxidation resistant coatings for tantalum alloys and other metals by L Sama( )

1 edition published in 1963 in English and held by 0 WorldCat member libraries worldwide

The effect of coating composition on structural changes and oxidation behavior was studied using a Sn-Al spray-slurry system with tantalum, tantalum alloys, columbium, tungsten and molybdenum. In tests conducted at 3000 F, it was found that increased oxidation protection was significantly related to the thickness of the tin-rich phase at the surface. Refractory metal powder additives plus excess aluminum to form aluminide particles served best to increase the thickness of this phase. Coating composition was optimized, and an extensive evaluation was carried out with Ta-10%W, Ta-30%Cb-7.5%V, and Cb-5 In oxidation tests at 1100 F to over 3000 F protective life was significantly affected by substrate composition, coating thickness and thermal cycling. Tensile and stress rupture data were obtained on coated samples at 2000 to 3000 F and correlated fairly well with data in the literature for uncoated material. Preliminary studies were made of coating stability at air pressures in the micron to millimeter range. Oxidation and diffusion effects were explored by metallographic electron probe and x-ray analysis. A brief study of Ta 10Hf-5W in contact with Al2O3 at elevated temperatures showed that this alloy was unstable in contrast to pure tantalum, Ta-10W, and Ta-30Cb 7.5V, which were quite stable
Study of failure mechanisms in high power radio frequency generating devices( )

1 edition published in 1962 in English and held by 0 WorldCat member libraries worldwide

The aim of this ivestigation is to determine failure mechanisms caused by residual gases in traveling-wave tubes and to study means of eliminating these gases in order to improve tube reliability. Gas spectra and electrical test data are shown for one tube operating at a severe life-test condition; correlation is made with tubes operating under a lower duty cycle. Gas ambient and gas sorption phenomena for tube components under operating conditions are presented for uncoated-cathode subassemblies and an oxide-coated cathode subassembly. In these subassemblies, the heater filament is the major gas source. (Author)
Study of adsorption of gases on solids in the high vacuum range by C. M Bliven( )

2 editions published between 1962 and 1963 in English and held by 0 WorldCat member libraries worldwide

An investigation of the interaction of nitrogen with a hot tungsten filament showed that a chemical pumping effect occurs. The magnitude of this effect and its variation with temperature is discussed. Preliminary results on the study of the effect of adsorbed oxygen on the work function of molybdenum at room temperature indicated that there are three stages in the adsorption process: during the first two stages, there is a rapid increase in the work function, whereas in the last stage there is a small increase and very slow rate of rise in work function
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English (26)