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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

A Comparison of the thermionic and photoelectric work function for platinum,

Koppius, Otto. January 1900 (has links)
Thesis (Ph. D.)--University of Chicago, 1920. / "Private edition, distributed by the University of Chicago libraries, Chicago, Illinois." "Reprinted from the Physical review, n.s., vol.xviii, no. 6, December, 1921." Also available on the Internet.
42

The Energy of photo-electrons from sodium and potassium as a function of the frequency of the incident light ... /

Kadesch, William Henry, January 1914 (has links)
Thesis (Ph. D.)--University of Chicago, 1915. / "Reprinted from the Physical review, n.s., vol. III, no. 5, May, 1914." Includes bibliographical references. Also available on the Internet.
43

The effects of pressure on the after-glow of nitrogen

Clayton, Henry Hubert January 1937 (has links)
[No abstract available] / Science, Faculty of / Physics and Astronomy, Department of / Graduate
44

A high-frequency discharge ion source

Chow, Richard Hing January 1949 (has links)
A high-frequency discharge ion source was developed yielding 45% protons in an 800 microampere, 14 kv energy focused beam of positive hydrogen ions. Higher ion currents could be delivered at higher voltages. The discharge was excited in a pyrex discharge tube, 1¼ inches in diameter and 9 inches long, by a 210 Mc/sec. push-pull, oscillator capable of delivering 120 watts power. An electrostatic potential difference of 1.8 kv applied axially with the discharge tube, accelerated the positive ions formed in the discharge toward the exit canal. A magnetic field of 240 gauss, also applied axially, shaped the discharge conically, and intensified the redness of the discharge, causing the Balmer lines to appear prominently when the discharge was viewed through a spectroscope. The ions emerging from the exit canal were focused by an electrostatic lens using a potential difference of 12 kv. The hydrogen pressure in the discharge tube measured 17 microns, and the rate of hydrogen consumption measured 11 cc. per hr. The proton percentage was found to depend on the oscillator power and critically on the gas pressure. The magnetic field increased the proton percentage, but in an unpredictable manner. It was also found that the focusing lens in front of the probe canal exerted an extracting action on the ions in the discharge; influencing very strongly the total ion beam current collected. The general performance of the ion source was found to be satisfactory. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
45

An investigation of radial recovery of a high current spark channel

Chan, Ping Wah January 1963 (has links)
Reignition curves have been obtained for a high current (40ka) spark gap channel in air at atmospheric pressure at various radial distances down to delay times of 50 µs. after initiation of spark. The reignition curves in the ‘thermal breakdown' regime are obtained by a constant voltage generator having a variable output ranging from 100 volts to 2.5 kv, while those in the 'spark breakdown' regime are obtained by the use of a restriking voltage generator having a higher voltage output ranging from 1 kv to 15 kv. The experimental results show that the gas at large radial distances recovers faster than that at a smaller distance. A special feature of the recovery curves is the occurrence of a dip which is thought to be the effect of a thermal wave. Gas temperatures are derived by using the equation of state, Paschen curves and the reignition measurements. A temperature profile of the spark channel has been obtained which indicates that the spark channel has a fairly uniform temperature up to a radial distance of 2.5 cm. Beyond this distance the temperature drops rapidly to ambient temperature at a radial distance of 4 cm, Deionization and recovery mechanisms are predicted theoretically and are verified during the earlier recovery period in which 'thermal breakdown' occurs and during the later recovery period when 'spark breakdown' is observed. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
46

Investigations of the glow phase in high pressure spark discharges

Lee, Chi-Sun January 1971 (has links)
The glow phase of high pressure spark discharges initiated by the Townsend mechanism of breakdown in hydrogen, nitrogen and carbon dioxide is studied using 16 ohm coaxial cable discharge techniques. Before the establishment of the spark channel in these low over-voltaged spark discharges, there exist two distinct transition stages, namely, a diffuse glow phase and a filamentary glow-to-channel transition phase. The optical appearance of the diffuse glow is similar to that of a normal d.c. glow discharge. It consists of a negative glow, a Faraday dark space, and a positive column. From our experimental results it is concluded that for the glow phase the cathode fall voltage and the ratio of the axial potential gradient to the gas pressure in the positive column are fixed for each gas. These values are independent of the impedance of the external circuit and the gas pressure. Comparisons with low pressure d.c. glow discharges indicate further that the cathode fall voltages are in agreement in both types of glow for the gases' investigated. In addition, a qualitative discussion about the transition nature of this diffuse glow phase is given on the basis of results obtained from spectroscopic investigations. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
47

Thermionic emission / by Arnold L. Reimann ...

Reimann, Arnold L. January 1934 (has links)
"Literature" at the end of each chapter. / Special Collections copy submitted together with 5 selected reprints as the author's thesis (D.Sc.)-- University of Adelaide, 1935. / xi, 324 p. : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (D.Sc.)--University of Adelaide, 1935
48

Surface restructuring of polydimethylsiloxane elastomers exposed to partial electrical discharge /

Kim, Jongsoo, January 2002 (has links)
Thesis (Ph. D.)--Lehigh University, 2002. / Includes bibliographical references and vita.
49

Fabrication and modeling of a floating-gate transistor for use as an electrostatic-discharge detector

Hsueh, Weichung Paul, 1962- January 1988 (has links)
Electrostatic discharge is of great concern to the electronics industry. It degrades and destroys large numbers of integrated circuits at every step from fabrication through packaging and testing. The goal of this research effort was the development of a device that can be used to obtain quantitative information on electrostatic discharge (ESD) in the integrated-circuit workplace. The device that was developed can be utilized in two different modes. (1) It can be used to form ESD test wafers or test chips. (2) It can be incorporated on product chips to give the ESD history of devices or monitor the process line. The technology that was examined in this work was that for floating-gate PROMS. A simple analytical model for obtaining a parameter called the ESD factor was developed. The prototype detector was designed, fabricated and tested in the Semiconductor Processing Facility of the University of Arizona. Evidence will be presented that the FLOTOX type of EEPROM functions well in its application as an ESD detector.
50

Electrical and radiation characteristics of the condensed spark discharge

Barker, L. M. (Lynn Marshall), 1928- January 1955 (has links)
No description available.

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