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Systems and techniques for suppressing the carrier signal using an optical delay element and an electrical interferometer in an opto-electronic noise suppression module.
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Electron microscopy and electron optical techniques in exobiology
Electron microscopy and optical techniques for biological Mars studies
Electron microscopy and electron optics in exobiology
Electron energy distribution functions were calculated in a U235 plasma at 1 atmosphere for various plasma temperatures and neutron fluxes. The distributions are assumed to be a summation of a high energy tail and a Maxwellian distribution. The sources of energetic electrons considered are the fission-fragment induced ionization of uranium and the electron induced ionization of uranium. The calculation of the high energy tail is reduced to an electron slowing down calculation, from the most energetic source to the energy where the electron is assumed to be incorporated into the Maxwellian distribution. The pertinent collisional processes are electron-electron scattering and electron induced ionization and excitation of uranium. Two distinct methods were employed in the calculation of the distributions. One method is based upon the assumption of continuous slowing and yields a distribution inversely proportional to the stopping power. An iteration scheme is utilized to include the secondary electron avalanche. In the other method, a governing equation is derived without assuming continuous electron slowing. This equation is solved by a Monte Carlo technique.
The electron drift technique is based on sensing the drift of a weak beam of test electrons that is caused by electric fields and/or gradients in the magnetic field. These quantities can, by use of different electron energies, in principle be determined separately. Depending on the ratio of drift speed to magnetic field strength, the drift velocity can be determined either from the two emission directions that cause the electrons to gyrate back to detectors placed some distance from the emitting guns, or from measurements of the time of flight of the electrons. As a by-product of the time-of-flight measurements, the magnetic field strength is also determined. The paper describes strengths and weaknesses of the method as well as technical constraints.
Electron-beam generator produces high quality welds without vaporization by relying on the mobility and hydrodynamic properties of the material in its liquid phase. The power density of the beam is relative to the speed of the workpiece, producing an inclined weld-front.
Electronic packaging methods for surveyor spacecraft modules such as the television system, discussing foam sandwich chassis construction and the use of cordwood modules
Electron microscopy technique for determining dispersoid distribution in powder blends
Electronic visualization technique for studying dynamic behavior of gas journal bearing
Electron cyclotron resonance plasma accelerator design for thrustor application and measuring techniques
Electron cyclotron resonance plasma accelerator design for thrustor application and measuring techniques
Electron microscope technique for revealing microstructures of dispersion strengthened materials
Temperature and density measurements in base region flow field of clustered rocket engine model using electron beam technique
Density and temperature measurement in base region flow field of clustered rocket model, using electron beam technique
Rotational temperature and density measurements in high speed gas flow by electron beam fluorescence technique
Report contains requirements for correction of instrumented data on the chemical composition of a specimen, obtained by electron microprobe analysis. A condensed review of electron microprobe techniques is presented, including background material for obtaining X ray intensity data corrections and absorption, atomic number, and fluorescence corrections.