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71.
ABSTRACT: How the quality of cold-smoked Atlantic salmon ( Salmo salar ) is affected by freezing the raw fish as whole fish, as gutted fish, and as fillets before smoking, and by freezing the finished product after smoking was studied. Freezing before smoking resulted in increased product yield and water content, but softer texture and increased K-value. Freezing reduced the content of astaxanthin but increased the lightness and the color intensity of the flesh. Gaping increased when the fish was frozen as fillets before smoking. Freezing only after smoking led to fewer changes in quality than freezing before smoking, whereas refreezing the finished products had little additional effect on quality. 相似文献
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在传统的信号配时中,都是以减少车辆的总延误为目标,这样并不能很好地体现出整个社会中人的时间价值。现以减少所有通过交叉口的出行者的总延误为目标,在传统的信号配时方案的基础上,提出了一套新的配时方案,同时以减少全部出行者的总延误时间为目标给出了相应的延误评价公式,最后以杭州市文一路-古翠路口的实测交通数据进行分析,论证了本配时方案的有效性。 相似文献
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75.
This paper deals with the non-steady-state kinetics of direct thermal initiated polymerization. The initiation is assumed to be a bimolecular reaction of the monomer. The relationship between the radical concentration and the monomer conversion is rigorously derived. In further treatment a few very close approximations are introduced based on the fact that the number of monomer molecules reacting in the initiation step is much less than that consumed in the propagation step for a process producing high polymer, and the value of the rate constant for propagation or chain transfer is much lower than that for chain termination. Expressions for various molecular parameters, such as molecular weight distribution, number-average and weight-average degrees of polymerization, and dispersity, are given. Several numerical examples are provided. 相似文献
76.
无间隙原子钢的微观结构特征和塑性应变比 总被引:1,自引:0,他引:1
采用X射线衍射的ODF和LP分析技术,SEM电子通道花样和蚀坑技术观测,研究了超深冲无间隙原子钢板的微观结构特征。结果表明:控制化学成分、保证基体纯净、优选工艺参数,促进强的γ-〈111〉∥N.D纤维织构的形成是获得优异成型性的关键。用CMTP方法,由ODF织构数据从理论计算了塑性应变比(r),表明rm值高达3.18。文中讨论了再结晶织构形成机制。 相似文献
77.
旋波媒质基本参数的一种测试方法 总被引:5,自引:0,他引:5
本文提出了直接利用旋波材料板的S参数获得其基本参数的方法。通过自由空间测量旋波材料板的反射场和透射场,可以反演得到媒质的复介电常数、复磁导率、旋波量以及透射场的轴比和旋转角,测试程序简单,结果精度高。 相似文献
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79.
《Drying Technology》2007,25(7):1275-1280
When using the convective drying method, the mass transfer between drying air and moisture diffusion of the material is very important. The moisture moves inside the material because of the volume change caused by the increased temperature. This movement is additionally affected by the texture of the material. According to the research dealing with colloid capillary porous texture of vegetables and fruit, the humidity migration inside the material occurs in both fluid and steam condition at the same time. This migration is stimulated by the heating and decreasing humidity along with the flow. In this research, winter varieties of apples (Jonathan, Golden Delicious, and Idared) were studied by heating of a 20 × 20 × 20 piece of apple with a thermocouple in it. On the basis of the measurements it can be stated that for the fruits with a high percentage of moisture (75-90%), when making the drying condition, the moisture gradient is influenced by the fractured cells of the cut area. It was found that the variety of apple is very important in relation to the heating and water loss gradient. According to the results, the wet volume change due to the heating highly influences the water loss. The models that describe the temperature of the material have a connection with the water loss. 相似文献
80.