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The technical and marketing characteristics needed in packaging systems to meet the needs of the distribution and retailing systems and of the consumer are described. Packages can serve a valuable purpose for advertising and conveying in formation.  相似文献   
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An apparatus based on the method of Jain and Krishnan was developed for property measurements in the temperature range from measurable radiant emission to the thermal stability limit of metallic materials. Apparatus and experimental techniques for cylindrical specimens with length-to-diameter ratios >4 are described. The theory of the method is reviewed, practical formulations are developed, and error sources are analyzed. The following properties were determined for zirconium carbide in the range 1000° to 2500°K: thermal conductivity, spectral thermal emittance at 0.65μ spectral thermal emittance at 0.65μ as a function of time in vacuum, electrical resistivity, and total thermal emittance. A compilation of experimental values for other physical properties of ZrC is given.  相似文献   
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Dehydrated proteins are frequently subjected to thermal stress in the presence of other components. The effect such substances may have upon protein structure, and therefore function, has not been fully investigated. Thus, the effect of added polyhydroxy components on the denaturation of lyophilized β-lactoglobulin, ovalbumin, and ribonuclease, as determined by differential scanning calorimetry, was evaluated. The denaturation temperature, Tm, of the globular proteins decreased in the dry state after the addition of sucrose, sorbitol, or glycerol. The thermal stability (based on Tm) of the dehydrated proteins appeared to correlate with the glass transition temperature (Tg) of the polyhydroxy component, which was assumed to be related to the Tg of the mixture. The lower the Tg of the component, the greater was the degree of protein destabilization. Thus, glass transition data may be used to predict the effect that a component would have on denaturation of dehydrated proteins at elevated temperatures.  相似文献   
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BACTERIAL SPOILAGE OF ICED FRESH CRABMEAT   总被引:1,自引:0,他引:1  
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Forage grasses and legumes growing in the soil covering four coal fly ash landfill sites in Central New York were sampled and analyzed for 20 elements. Selenium, boron and molybdenum were most consistently higher in concentration in these crops than the corresponding control plants sampled from adjacent upwind locations. Legumes absorbed greater amounts of these elements than grasses probably owing to their deep-rooted penetration of the fly ash layer below. Factors affecting the extent of absorption of these elements by the crops and the agricultural significance as related to grazing farm animals are discussed.  相似文献   
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ABSTRACT Laboratory-reared king salmon were harvested using CO2 anesthetizing (CO2) or by rested harvesting techniques using AQUI-S(tm) anesthetizing (AQUI-S). Fish were killed by spiking, and flesh portions were stored in air packs (0°C) for 22 d. Headspace oxygen levels, sensory characteristics (raw and cooked), tensile properties, drip loss, gaping, pH, nucleotide derivatives, color, and bacterial counts were determined after 5 to 22 d of storage. All parameters except tensile properties showed significant trends with storage time. Oxygen levels were consistently lower in CO2 packs whereas, on average, drip was lower in AQUI-S samples, and L*-values and bacterial numbers were higher in AQUI-S samples. Overall, harvesting effects had minimal impact on the quality parameters measured.  相似文献   
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This paper specifies the main features of connectionist and brain-like connectionist models; argues for the need for, and usefulness of, appropriate successively larger brainlike structures; and examines parallel-hierarchical Recognition Cone models of perception from this perspective, as examples of networks exploiting such structures (e.g. local receptive fields, global convergence-divergence). The anatomy, physiology, behavior, and development of the visual system are briefly summarized to motivate the architecture of brain-structured networks for perceptual recognition. Results are presented from simulations of carefully pre-designed Recognition Cone structures that perceive objects (e.g. houses) in digitized photographs. A framework for perceptual learning is introduced, including mechanisms for generation learning, i.e. the growth of new links and possibly, nodes, subject to brain-like topological constraints. The information processing transforms discovered through feedback-guided generation are fine-tuned by feedback-guided reweighting of links. Some preliminary results are presented of brain-structured networks that learn to recognize simple objects (e.g. letters of the alphabet, cups, apples, bananas) through generation and reweighting of transforms. These show large improvements over networks that either lack brain-like structure or/and learn by reweighting of links alone. It is concluded that brain-like structures and generation learning can significantly increase the power of connectionist models.  相似文献   
10.
At steelmaking temperatures, carbon and oxide constituents of BOF refractories react via the vapor phase. The mechanism of these reactions involves the production of metal or suboxide vapor in a region of low O2 pressure and may include reoxidation and condensation in a region of high p O2. The faster wear rate of pitch-bonded brick in high-wear areas of the BOF, as compared to burned impregnated brick, is attributed to the pronounced porous region created near the hot face when internal oxidation-reduction reactions consume the carbon bond.  相似文献   
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