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Campbell, J. P.

Publications and source records attributed to Campbell, J. P..

At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2015

Interface-state capture cross section—Why does it vary so much?

A capture cross section value is often assigned to Si–SiO{sub 2} interface defects. Using a kinetic variation of the charge pumping technique and transition state theory, we show that the value of capture cross section is extremely sensitive to the measurement approach and does not provide any meaningful insight into the physics involved. We argue that capture cross section is neither a physical property of interface defects nor is there any need to assign capture cross section values.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
NASA NTRS1977

Recent research on powered-lift STOL ground effects

Early studies of powered-lift STOL concepts indicated that a basic problem of aircraft incorporating such concepts would be a serious adverse ground effect on lift. Experience to date with actual powered-lift STOL aircraft, however, has not borne out this concern. This apparent disagreement is examined and recent research data are used to help explain some of the differences observed. Analysis indicates that most of the disagreement can be attributed to the use of wind tunnel data that were not directly applicable to the airplane because the model did not properly represent some of the design features and operating conditions of the airplane.

Campbell, J. P.↗
NASA NTRS1976

Overview of powered-lift technology

The concept and application of powered lift and the effects of some fundamental design variables are discussed. A brief chronology of significant developments in the field is also presented and the direction of research efforts in recent years is indicated. All powered lift concepts are included, but emphasis is on the two externally blown schemes which involve blowing either above or below the wing and which are utilized in the YC-14 and YC-15 aircraft. Aerodynamics and vehicle design are emphasized. The areas of acoustics, propulsion, and loads are briefly considered.

Campbell, J. P.↗
NASA NTRS1971

Visible and near-ultraviolet spectra of low-pressure rare-gas microwave discharges

The spectral emission characteristics of three commercial low pressure rare gas discharge lamps wire obtained in the near ultraviolet and visible wavelength range. All three lamps show a definite continuum over the entire wavelength range from 0.185 to 0.6 micrometers. Considerable line emission is superimposed on much of the continuum for wavelengths greater than 0.35 micrometers. These sources were used to make transmittance measurements on quartz samples in the near ultraviolet wavelength range.

Campbell, J. P.↗
NASA NTRS1966

Experimental investigation of megawatt dc arc heating of nitrogen

Four types of arc heaters, each with the capability of providing arc power levels in excess of 1 megawatt in nitrogen, were tested over a range of power levels and nitrogen flow rates to determine their value as heaters for hypersonic tunnels. The data derived should be useful in the design of high energy heaters for various industrial processes.

Boldman, D. R.↗