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991.
Beef and pork frankfurters were produced with 0, 5, 10, and 15% of the meat block being mechanically separated spleen (MSS). No fatting or peelability problems were experienced. Frankfurters were held at 2°C and evaluated at 2-wk intervals for 6 wk. Consumer panelists rated all products acceptable. A bi-monthly laboratory taste panel evaluated all frank furters (except the 15% product) acceptable during storage. Allo-Kramer shear values decreased with increased MSS, Frankfurters with 5, 10, and 15% MSS had 2.2, 3.9, and 4.9 times more iron than the control, respectively. Level of MSS did not influence bacterial numbers.  相似文献   
992.
A new technique for mixing optical waves to generate microwave-frequency signals using an injection laser diode and a fibre-optic interferometer is reported. A beat signal is produced by interfering light from the laser with light from the same laser emitted earlier at a different frequency. The interferometer consists of an evanescent-field fibre coupler joined to a length of single-mode optical fibre. The laser is tuned by pulsed or bipolar current waveforms superimposed on a DC bias current. Feedback from an external cavity stabilises the laser frequency and reduces its linewidth. Efficient mixing at difference frequencies from 250 MHz to 2 GHz is obtained, with spectral widths of less than 1% of the centre frequency.  相似文献   
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996.
The "Wisconsin process'(a combination of lactic acid starter culture and sucrose) has previously been shown to be effective in preventing botulinum toxigenesis in reduced nitrite bacon. This technology has been applied to other low-acid refrigerated foods which receive less than a 12D thermal process. A combination of Pediococcus acidilactici and dextrose was effective in preventing botulinum toxigenesis in chicken salad. When the chicken salad was temperature abused, the P. acidilactici catabolized available dextrose to lactic acid. Extracellular accumulation of the lactic acid caused a decrease in the pH of the product. Pathogen challenge tests verified that the rate and extent of lactic acid accumulation in the chicken salad during temperature abuse was sufficient to preclude botulinum toxigenesis. This technology has the potential to be of use in a variety of low-acid refrigerated foods.  相似文献   
997.
A microprocessor-based system with 32 A/D, 24 D/A, and 16 ac load controllers, has been designed and built to monitor and control an ion beam thin-film deposition system. The A/D and D/A channels have electrical isolation of 7.5 kV between channels and between input and output. The microprocessor system keeps the ion beam deposition parameters stable for extended periods of operation and it is proposed as a means to greatly simplify switching from one deposition species to another to grow thin multilayer or alloy films.  相似文献   
998.
Cotton fabric was crosslinked with five agents, three of which were prepared form formaldehyde and two of which were formaldehyde-free. The formaldehyde-free agents produced less bonding between layers in the laminated microstructure of the cotton fiber. One agent, 4,5-dihydroxy-1,3-dimethyl-2-imidazolidinone, gave no evidence of any interlayer bonding. All five agents gave the same relationship between wrinkle recovery angle and molar substitution on the cotton up to moderate recovery angles, but only agents based on formaldehyde gave higher wrinkle recovery angles with additional reaction. Intralayer crosslinking did not reduce absorptivity, as shown by moisture regain and dye receptivity, but did restrict swelling in cupriethylenediamine hydroxide to the same extent as combined interlayer and intralayer crosslinking. The decrease in extensibility of treated fabric with increasing wrinkle recovery angle was the same with all agents. These results indicate the regions of the fiber that are important for each of these properties.  相似文献   
999.
The phospholipids of the spongePolymastia gleneni contain saturated long chain (C22–30)-acetoxy fatty acids. Their structures were assigned based on chromatographic and spectrometric data as well as comparison with a synthetic sample. The use of capillary gas chromatography combined with chemical ionization and electron impact mass spectrometry was instrumental in the eludication of structures, since only a very small amount of crude lipids was available. Part 10 of “Phospholipids in Marine Organisms.” For Part 9 in this series, see reference 12.  相似文献   
1000.
Broadline nuclear magnetic resonance measurements have been carried out for the proton resonance in oriented poly(vinylidene fluoride). The spectra in general show two component lines with distinctly different line widths. The broad component shows a high degree of molecular orientation and can be satisfactorily assigned to the crystalline regions of the polymer. The narrow component corresponds to an oriented non crystalline phase which is sufficiently constrained to allow motion about the chain axis only. An appreciable decrease in the value of the rigid mass fraction was observed in both of the samples over the temperature range examined. Our calculations indicate that this could play an important role in the temperature dependence of the pyroelectric response of this material.  相似文献   
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