摘要:
A method for evaluating the crosslink concentration in a crosslinked rubber is provided. The present invention relates to a method for evaluating the crosslink concentration in a crosslinked rubber by small-angle X-ray scattering or small-angle neutron scattering using measurement samples prepared by swelling the crosslinked rubber to different degrees of swelling.
摘要:
An X-ray backscatter imaging system uses frequency modulated X-rays to determine depth of features within a target. An X-ray source generates X-ray radiation modulated by a frequency-modulated bias current. The X-ray radiation impinges upon and is backscattered from multiple depths within the target. A scintillating material receives the backscattered X-rays and generates corresponding photons. A photodetector, having gain modulated by the frequency modulation signal from the local oscillator, receives the photons from the scintillating material and generates an analog output signal containing phase delay information indicative of the distance travelled by the X-rays backscattered from multiple depths within the target. The analog output signal is sampled by an analog-to-digital converter to create a digital output signal. A computer processor performs a discrete Fourier transform on the digital output signal to provide target depth information based on the phase delay information.
摘要:
Disclosed is an imaging apparatus for generating data of a phase image based on an interference pattern acquired by a shearing interferometer, including: a differential phase data calculating unit that calculates first differential phase data expressing a change of a phase in a first direction and second differential phase data expressing a change of a phase in a second direction, based on interference pattern data generated by an electromagnetic wave transmitted through a subject; a second-order differential phase data calculating unit that calculates first second-order differential phase data by differentiating the first differential phase data in the first direction, and calculates second second-order differential phase data by differentiating the second differential phase data in the second direction; and a phase data calculating unit that calculates the phase image by solving a second-order differential equation including the first and second second-order differential phase data as functions.
摘要:
Apparatus and methods for coherent diffractive imaging with arbitrary angle of illumination incidence utilize a method of fast remapping of a detected diffraction intensity pattern from a detector pixel array (initial grid) to a uniform spatial frequency grid (final grid) chosen to allow for FFT on the remapped pattern. This is accomplished by remapping the initial grid to an intermediate grid chosen to result in a final grid that is linear in spatial frequency. The initial grid is remapped (generally by interpolation) to the intermediate grid that is calculated to correspond to the final grid. In general, the initial grid (x,y) is uniform in space, the intermediate grid ({tilde over (x)},{tilde over (y)}) is non-uniform in spatial frequency, and the final grid ({tilde over (f)}x,{tilde over (f)}y) is uniform in spatial frequency.
摘要:
System and methods for decomposing an Auger electron spectrum into elemental and chemical components, includes conditioning and input spectrum to generate a normalized input spectrum; determining statistical correlation between the normalized input spectrum and stored elemental spectral signatures; and characterizing elemental or chemical species in the input spectrum from the statistical correlation, wherein said conditioning the input spectrum includes estimating a background signal of non-Auger electrons in the input spectrum and subtracting the estimated background signal from the input spectrum.
摘要:
Measurements are made on a sample (1) to obtain an experimental profile (2) having structural features (3, 4) determined at least in part by the given characteristic and an expected profile (5) calculated for the sample using selected parameters. A degree of smoothing is applied to the experimental profile (2) to reduce the structural features (3,4) thereby producing a smoothed experimental profile (21 a) and the same degree of smoothing is applied to the calculated profile (5) to produce a smoothed calculated profile 51 a. The smoothed calculated profile (51 a) is compared with the smoothed experimental profile (21 a) to determine the difference between the smoothed profiles. The calculated profile is then modified by varying at least one of the parameters until the smoothed modified profile fits the smoothed experimental profile. The above steps are then repeated with the modified calculated profile using each time a degree of smoothing less than the previous time so that the structural features return and the final modified calculated profile (5b) provides a desired fit to the experimental profile (2) thereby enabling the given characteristic to be determined from the parameters used for the final modified profile.
摘要:
Apparatus and methods for coherent diffractive imaging with arbitrary angle of illumination incidence utilize a method of fast remapping of a detected diffraction intensity pattern from a detector pixel array (initial grid) to a uniform spatial frequency grid (final grid) chosen to allow for FFT on the remapped pattern. This is accomplished by remapping the initial grid to an intermediate grid chosen to result in a final grid that is linear in spatial frequency. The initial grid is remapped (generally by interpolation) to the intermediate grid that is calculated to correspond to the final grid. In general, the initial grid (x,y) is uniform in space, the intermediate grid ({tilde over (x)},{tilde over (y)}) is non-uniform in spatial frequency, and the final grid ({tilde over (f)}x,{tilde over (f)}y) is uniform in spatial frequency.
摘要:
An X-ray backscatter imaging system uses frequency modulated X-rays to determine depth of features within a target. An X-ray source generates X-ray radiation modulated by a frequency-modulated bias current. The X-ray radiation impinges upon and is backscattered from multiple depths within the target. A scintillating material receives the backscattered X-rays and generates corresponding photons. A photodetector, having gain modulated by the frequency modulation signal from the local oscillator, receives the photons from the scintillating material and generates an analog output signal containing phase delay information indicative of the distance travelled by the X-rays backscattered from multiple depths within the target. The analog output signal is sampled by an analog-to-digital converter to create a digital output signal. A computer processor performs a discrete Fourier transform on the digital output signal to provide target depth information based on the phase delay information.
摘要:
A method of using electron diffraction to obtain PDFs from crystalline, nanocrystalline, and amorphous inorganic, organic, and organometallic compound.
摘要:
An apparatus for analyzing the spectral data in an elemental analyzer measuring gamma rays arising from neutron capture in bulk substances is disclosed. The formation of optimally-weighted linear sums of the number of counts in various portions of the energy spectrum of neutron-capture gamma rays improves measurement accuracy in an apparatus for on-line elemental analysis of bulk substances. Within the apparatus, the analyzed bulk substance is exposed to neutrons, and neutron capture generates prompt gamma rays therefrom. A detector interacts with some of these gamma rays to produce electrical signals used to convert their energy spectrum to digital form by pulse-height analysis. A small computer uses this digitized spectrum to construct the weighted linear sums corresponding to at least one interesting element. Generally, several elements are measured, and the computer forms ratios between the elemental sums to provide relative concentration measurements which are independent of absolute counting rates. The instrument also contains a calibration plug to verify performance, a digital data link to allow the computer to be remote from the gamma-ray detector and devices to display the results of the measurement and/or to communicate them to external equipment. Measurement of an element principally present in the instrument structure permits the computer to correct the measurement of an interesting element in the bulk substance for its presence in the structure.