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1.
The textural deterioration of cod muscle during frozen storage was investigated by objective measurement using the Instron Universal Testing Machine. The rates of texture change as a function of storage time revealed that the increased toughness and decreased cohesiveness could be described by a first-order relationship. Higher storage temperatures resulted in more rapid rates of textural deterioration. Larger activation energy constants for toughness of cod muscle as compared to cohesiveness indicated that toughening was more temperature dependent than cohesiveness. The increased toughness and the decreased cohesiveness of frozen-stored fish appeared to be related to the protein denaturation of the cod muscle and the loss of water-holding capacity, respectively.  相似文献   
2.
The sensitivity of the optimal response of a linear system with quadratic performance index to changes in the weighting factors in the performance index is determined. This necessitates finding the sensitivity of the feedback gain matrix K to changes in the weighting factors. It is shown that the sensitivities of K can be obtained as the solution of a set of linear matrix differential equations. Further, for time-invariant systems and an infinite time interval, it is seen that the sensitivities of K are found more simply by solving a set of linear algebraic matrix equations.  相似文献   
3.
This paper deals with a new storage structure layout method called ‘cubic-in-time’, for minimizing the travel time of selected handling equipment in a three-dimensional palletized storage system. Storage-system design algorithms for minimizing travel times are described, the results are analysed, and some general conclusions are drawn.  相似文献   
4.
倪萌 《电源技术》2007,31(10):777-778
建立了一个数值模型,来计算并论述在固体氧化物燃料电池(SOFC)阴极中的扩散和渗透共同作用下的传质现象.经过对比分析,研究了阴极内压力梯度对气体传输、气体分布,以及浓度过电压的影响.研究表明,文献中所采用的扩散模型可近似模拟SOFC阴极的浓度过电压.但是,对于气体成份沿阴极的分布,则必须考虑压力梯度的影响.在此提出的模型可进一步深化,以优化SOFC电极的多孔结构.  相似文献   
5.
Starch noodles were prepared using potato starch from 8 genotypes, mung bean starch, mung bean-potato starch blends, and sweet potato starch. The cooking quality of noodles from selected potato starches compared well with commercial starch noodles. Of the unblended potato starches, Mainechip exhibited cooking quality similar to commercial starch noodles with respect to cooking loss, cooked weight, and ?rmness. Appearance and texture of starch noodles from three genotypes (E55-35, Mainechip, and Shasta) were evaluated by a trained sensory panel. Noodles made from unblended potato starches had higher glossiness and transparency than those from other starches. Noodles from both un-blended and blended Mainechip starch had the highest press and elasticity.  相似文献   
6.
In this paper we test various implications of a managerial lifecyclehypothesis. In particular we examine whether (i) relativelyyoung firms have returns on investment greater than their costof capital, and (ii) mature firms have returns on investmentless than their cost of capital Support is found for both predictionsin a sample of US companies.  相似文献   
7.
THE AUTHOR'S WIFE SMOKED CIGARETTS ONLY WHEN SEATED IN A PARTICULAR CHAIR. SITTING IN THE CHAIR PRODUCED TIME OUT FROM VARIOUS SOCIAL AND ENVIRONMENTAL REINFORCERS (E.G., CONVERSATION, TV). AN IMMEDIATE SHARP REDUCTION IN SMOKING RATE WAS OBSERVED. WHEN THE SMOKING CHAIR WAS SUBSEQUENTLY MADE LESS READILY AVAILABLE A FURTHER REDUCTION IN SMOKING RATE OCCURRED. IT IS SUGGESTED THAT REINFORCING STIMULI OTHER THAN CIGARETTES WERE INVOLVED IN MAINTAINING S'S NORMAL SMOKING RATE. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Based on a first-principles scattering theory applicable to small to moderate incidence angles, a new imaging model for ocean features is proposed. In contrast to the Alpers and Hennings Bragg-based model, the new model incorporates the full ocean wave spectrum, utilizes Hughes' suggested spectral decay rate formula and contains no adjustable parameters. For typical ocean currents, the new model predicts realistic values for L-band cross section modulations and comparable L-band and X-band cross section modulations. These latter results are shown to be due to backscatter from ocean waves that are significantly longer than the Bragg resonant wave. By comparison the Bragg-based imaging model is shown to predict that X-band modulations will be at least one order of magnitude weaker than L-band modulations.  相似文献   
9.
10.
Calcium bioavailability to rats was compared from CaCl2 (28 mM), CaCO3, fresh milk, milk adjusted to pH 5.35, and Cheddar cheese. The cheese was manufactured from pasteurized bovine milk and all doses were labeled extrinsically with 45Ca and 47Ca and administered orally to rats. One label (45Ca) was added to milk before cheese manufacture and the other (47Ca) was added to the cheese 24 h prior to dosing. Calcium bioavailability was determined by: 1) absorption measured by whole body counting, and 2) availability for bone metabolism assessed by bone radioactivity measurements. Calcium absorption averaged 76.8% and was not affected by length of ripening (p>0.05). Absorption from CaCl2, CaCO3, fresh milk, milk at pH 5.35, and the cheeses was similar. The two methods gave similar estimates of relative bioavailability. The ratio of 47Ca absorption to 45Ca absorption for any cheese sample was significantly greater than 1, indicating extrinsic labels added after processing may overestimate Ca absorption from cheese.  相似文献   
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