Diffraction of a pulse by a three-dimensional corner
Three dimensional diffraction of sonic booms by corners of structures
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Three dimensional diffraction of sonic booms by corners of structures
Approximative solutions for diffracted and focusing wave front expansions in sonic boom shock wave propagation
Pressure pulse diffraction by three dimensional structural corner subjected to sonic boom
Electron microscope, electron diffraction, and electron microprobe analysis of defective solid state weldment on liquid hydrogen tank from Apollo 12 fuel cell system
Surface plasma resonance effect in diffraction gratings and relation of effect to space contamination by spacecraft instruments
Calculation of near fields of reflector antennas by geometrical theory of diffraction
Shock wave diffraction by two dimensional weak disturbances, using aerodynamics blast method
Far field diffraction pattern of corner reflector for normally incident monochromatic light, considering polarization characteristics
Isolated ionospheric irregularities, describing refraction and diffraction pattern calculations for satellite signals
Laboratory model for radio star scintillation and other diffraction phenomena by thin weak random phase changing screen including earth atmosphere or solar wind
Short N wave refraction and diffraction by gas- filled soap bubble, discussing measurements to explain peaking and rounding in sonic boom pressure signature
High resolution X ray diffraction patterns of yeast phenylalanyl transfer RNA crystals, discussing double helical regional distribution characteristics
High temperature phase transition and composition of Apollo 12 pigeonite/augite clinopyroxene crystal rock 12021 from X ray diffraction
Exsolution lameccae structure of Lunar pyroxenes from Apollo 12 samples, using electron microscopy and diffraction
Methods were developed for quantitative analysis by X-ray diffraction of the oxides Al2O3, NiO, Cr2O3, CoO, and CoCr2O4 within a standard deviation of about 10 percent of the weight fraction reported or within 1 percent absolute. These error limits assume that the sample oxides are well characterized and that the physiochemical structure of the oxides in the samples are identical with those in the synthesized standards. Results are given for the use of one of the techniques in the analysis of spalls from a series of oxidation tests of the cobalt base alloy WI-52.
Experimental and theoretical demonstration of the necessity to take into account the effects of diffraction at a spectrometer's entrance slit in adjusting the spectrometer for observation of fast-beam spectral lines under conditions of minimum linewidth. An approximate expression is obtained for the optimum entrance slit width to be used in order to avoid the pronounced broadening of the spectral lines that occurs for very narrow entrance slits.
A simple visual test for the evaluation of concave diffraction gratings is described. It is twice as sensitive as the Foucault knife edge test, from which it is derived, and has the advantage that the images are straight and free of astigmatism. It is particularly useful for grating with high ruling frequency where the above image faults limit the utility of the Foucault test. The test can be interpreted quantitatively and can detect zonal grating space errors of as little as 0.1 A.
An asymptotic solution for large spacing is obtained in the problem of diffraction by an aperture between two conducting wedges. The variation of the wedge angles is shown to have significant effect on the far field amplitude of the transmitted field in certain ranges of angle for E-polarization. The wedge angles are seen to have a greater effect than interaction corrections in some cases but a lesser effect in others. Numerical comparisons are carried out.