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991.
992.
Uytterhaegen L Claeys E Demeyer D Lippens M Fiems LO Boucqué CY Van de Voorde G Bastiaens A 《Meat science》1994,38(2):255-267
Carcass properties and meat quality characteristics of 32 Belgian Blue White double-muscled bulls (DM) were compared with those of 59 bulls of the same breed with normal conformation (N). DM showed superior carcass quality as revealed in increased dressing percentage, meat production yield, conformation grade, muscle/fat and muscle/bone ratios (all P < 0·001). Longissimus dorsi (LD) shear force values, drip and cooking losses at 8 days post mortem (pm) were significantly higher (P < 0·001) for DM, whereas sarcomere lengths were not different. Calpain 1 and calpastatin levels at 1 h and 24 h pm were tremendously decreased in DM as were also cathepsin B and L levels at 1 and 8 days pm (P < 0·001). As evident from semi-quantitative SDS-PAGE, these differences were accompanied by higher titin and lower 30 kDa levels (P < 0·001) in DM. Troponin-t levels were not different, but very low. Intramuscular collagen content was significantly lower in DM (P < 0·001). This suggests that lower background toughness in DM was compensated for by reduced post-mortem proteolytic tenderization. Discrepancy with literature reports regarding tenderness of DM might be related to the extreme muscularity of the Belgian Blue White breed, compared to other DM breeds. The results also suggest that reduced protein turnover might be involved in the muscle hypertrophy phenomenon within this breed, because of likely reduced levels of calpains and cathepsins in living DM animals. 相似文献
993.
Ultrathin silane monolayer and silicon oxide alignment layers in surface-stabilized ferroelectric liquidcrystal devices are shown to enhance bistability and reduce degradation from ions. 相似文献
994.
Chirp filtering in the fractional Fourier domain 总被引:2,自引:0,他引:2
In the Wigner domain of a one-dimensional function, a certain chirp term represents a rotated line delta function. On the other hand, a fractional Fourier transform (FRT) can be associated with a rotation of the Wigner-distribution function by an angle connected with the FRT order. Thus with the FRT tool a chirp and a delta function can be transformed one into the other. Taking the chirp as additive noise, the FRT is used for filtering the line delta function in the appropriate fractional Fourier domain. Experimental filtering results for a Gaussian input function, which is modulated by an additive chirp noise, are shown. Excellent agreement between experiments and computer simulations is achieved. 相似文献
995.
The cross-correlation function between two light fields is recorded with the help of a new device. The proposed correlator exhibits ultrashort time resolution. The optical path difference between the two interfering beams does not have to be known with interferometric precision. The experimental dynamic range proved to be as large as 10(5). The device features imaging capabilities that could be applied to the analysis of two-dimensional images with ultrashort time resolution. 相似文献
996.
Optical wavelet matched filter 总被引:1,自引:0,他引:1
A shift-invariant optical continuous wavelet transform is used for pattern recognition. We propose an Voptical wavelet matched filter that performs optical wavelet transforms for edge enhancement and the correlation between two wavelet transforms in a single step. This new bandpass matched filter shows improved discrimination capability with respect to the conventional matched filter and improved signal-to-noise ratio with respect to the phase-only matched filter. The wavelet matched filter provides flexibility of an adaptive choice of the scale factors of the wavelets that permit the selection of size and orientation of the smoothing function used in edge enhancement and the optimization of the performance of the filter. Optical experimental results are shown. 相似文献
997.
Photon counting with passively quenched germanium avalanche 总被引:1,自引:0,他引:1
We demonstrate photon counting in germanium avalanche photodiodes biased beyond breakdown and quenched with a simple series resistance circuit. The devices show moderate (> 7%) quantum efficiency with limited afterpulsing and dark counts and subnanosecond jitter. 相似文献
998.
Ring resonator for lasers with annular gain media 总被引:1,自引:0,他引:1
A ring resonator for lasers with annular gain media is presented. The resonator consists of two annular mirrors. While the radiation is reflected back and forth between the two annular mirrors, diffraction effects induce an additional azimuthal radiation flux. Output coupling is obtained through a decentered coupling aperture on the circumference of one of the two mirrors. The azimuthal radiation flux permits the extraction of optical power from the whole gain volume through the coupling aperture. The azimuthal radiation flux can revolve in two directions. The associated modes are degenerate, and random jumping between unidirectional and bidirectional operation is observed. Unidirectional operation has been stabilized but remains very sensitive to mirror alignment. High extraction efficiencies have been demonstrated experimentally with this resonator with a diffusion-cooled CO(2) laser and 2 times diffraction-limited beams have been obtained. An empty resonator model that shows the effect of edge diffraction at the coupling aperture on the resonator modes is also given. 相似文献
999.
A novel-type Raman cell especially suitable for the generation of tunable vacuum ultraviolet (VUV) radiation with pump radiation from a frequency-doubled dye laser is described. This hydrogen-filled Raman cell permits the generation of narrow-bandwidth radiation to below 114 nm. Absolute VUV energies in the various anti-Stokes orders and measurements of pulse durations and pressure dependences are given. 相似文献
1000.
We consider a computer-generated hologram for the one-dimensional collimation in x of the output from a linear laser-diode array in y. Our concern is to produce one-dimensional pencil beams from each laser diode with small cross talk between the output from the separate laser diodes. Such outputs can be used in matrix-vector, neural net, and interconnection applications. The efficiency and the design of the computer-generated hologram are detailed, and initial optical laboratory results with an electron-beam recorded computer-generated hologram are presented. 相似文献