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A direct‐diode pumped Ti:sapphire femtosecond oscillator is used to perform multiphoton imaging for the first time.  相似文献   
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The quest for improved efficiency has motivated the elevation of turbine inlet temperatures in all types of advanced aircraft gas turbines. The accommodation of higher gas temperatures necessitates complex blade cooling schemes so as not to sacrifice structural integrity and operational life in advanced engine designs. Estimates of the heat transfer from the gas to stationary (vanes) or rotating blades poses a major uncertainty because of the complexity of the heat transfer processes. The gas flow through these blade rows is three-dimensional with complex secondary viscous flow patterns that interact with the end walls and blade surfaces. In addition, upstream disturbances, stagnation flow, curvature effects, and flow acceleration complicate the thermal transport mechanisms in the boundary layers. Some of these fundamental heat transfer effects will be discussed. The chief purpose of this paper is to acquaint those in the heat transfer community, who are not directly involved in gas turbines, with the seriousness of the problem and to recommend some basic research that would improve the predictions of gas-side heat transfer on turbine blades and vanes.  相似文献   
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Muscles were excised from the shoulders of U.S. No. 1 pork carcasses within 1h postmortem. Samples were flaked as; small (head opening = 3.0mm), medium (head opening = 6.1mm) and large (head opening = 9.9mm) with an Urschel Comitrol 3600. Samples were formulated with 1.0 NaCl and 0.25% sodium tripolyphosphate (STP), converted into 19 mm thick restructured chops and packaged. Subjective evaluations were conducted after 5 and 56 days of frozen storage for color, cohesiveness, muscle cut resemblance, overall appearance, tenderness, juiciness, connective tissue amount and flavor. Objective measurements included Hunter Color values, shear force, percentage cooking loss and Thiobarbituric Acid (TBA) values. Results suggested that large flaked particles contributed to improved color and reduced cooking loss. Particle size had no effect on muscle cut resemblance, overall appearance, juiciness and flavor. Increased particle size was responsible for decreased tenderness, cohesiveness and TBA values but increased connective tissue amount.  相似文献   
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Soluble peroxidase activity increased dramatically during the early stages of tomato fruit development, reaching a maximum at the mature-green stage. Ionically and covalently bound peroxidases were also observed, and the activities of these fractions increased steadily throughout fruit development. IAA (indoleacetic acid) oxidase activity was observed in both soluble and bound fractions and paralleled the peroxidase activity. Tissue homogenates from juvenile fruit caused an extended induction period in IAA oxidation reactions catalyzed by the purified tomato fruit peroxidase, suggesting the occurence of a high concentration of phenolic-type auxin protectors in this tissue. As the fruit developed, tissue homogenates showed a reduction in the amount of auxin protectors as the IAA oxidizing capacity of the fruit increased.  相似文献   
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SUMMARY –Pilot-scale extractions of orange peel color concentrates from whole peel, peel frits and flavedo were reported. Yields of color up to 402, 545 and 669 mg/kg of starting material were obtained from frits, whole peel and flavedo, respectively. Additional color was obtained by acetone treatment of emulsion and this process increased yields by 1% from whole peel, 33% from flavedo and 50% from frits. All three of these waste materials appear to provide good sources of natural orange color. From the standpoint of yield, flavedo was best. Whole peel, although affording the lowest yield of color, offers the advantage of being considerably easier to handle due to lack of emulsion.  相似文献   
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Quantitative data were obtained for total carbonyls, total monocarbonyls, methyl ketones, saturated aldehydes, 2-enals and 2,4dienals from fresh, reduced surface flora (Dip) and inoculated muscle samples incubated at the optimal growth temperature of the respective bacteria. Individual monocarbonyl compounds were identified by thin-layer and gas liquid chromatography. Micrococcus cryophilus, Pseudomonas fluorescens and Staphylococcus aureus decreased total carbonyls by 57, 18 and 43%, respectively, and total monocarbonyls by 53, 20 and 33%, respectively. Pediococcus cerevisiae increased the total carbonyl and total monocarbonyl content by 70 and 71%. Concentrations of carbonyls in the control samples were directly related to temperature of incubation. Methyl ketones, saturated aldehydes, 2-enals and 2,4dienals were decreased by M. cryophilus, Ps. fluorescens and S. aureus but each monocarbonyl class was increased by P. cerevisiae.  相似文献   
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Spectroradiometry is fundamental in the measurement and evaluation of color. It is used in the evaluation of new light sources, in the analysis of problem areas, and for the compilation of data for inclusion in the technical brochures describing lighting products. The basic elements of a spectroradiometer are described and the application of spectral-power distribution measurements to photometry and colorimetry is illustrated.  相似文献   
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