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31.
The physicochemical properties of sesame 13S globulin gels containing fatty acid salts (FAS) were investigated. The softness, water-holding ability and transparency of the gels markedly increased in the presence of sodium oleate (NaCl18:1) or sodium linoleate (NaC18:2) at a 75 molar ratio to a molecule of the 13S globulin. The effect was not observed by the addition of sodium caprylate (NaC8:0). Scanning electron microscopy showed that a very fine network structure was formed in the gel with 75 molar ratio of NaC18:2. The addition of a suitable amount of FAS having a moderate length and an unsaturated carbon chain could improve the water-holding ability and transparency of the 13S globulin gel.  相似文献   
32.
This paper is concerned with (1) the problem of the construction of lower-order models and (2) the Telated problem of the order determination of a real system based upon an estimated model with an overestimated order. Methods of the construction of stable lower-order models and the system-order determination are proposed. The approach adopted is to obtain a minimal realization of the original system by taking the principal components of the predictors of the outputs as the state and then to construct reduced models based upon a measure of reducibility defined in connection with the minimal realization algorithm. The measure of reducibility is useful to get a priori information about how small the order of the reduced model can be without much deterioration. Simulation studies are also carried out to demonstrate the effectiveness of the measure of reducibility and the proposed methods.  相似文献   
33.
Continuous fermentation of grape juice was carried out in a packed bed column system using Lactobacillus casei adsorbed onto ceramic beads. Chemical components in the reaction vessel of this system were compared with those of a free-cell fermentation. No major differences were noted in the principal components. Diacetyl and methionine levels decreased, however, whereas aspartic acid and cysteine increased. Silica levels increased immediately after initiation of the immobilized cell culture due to elution from the ceramic carrier beads. In two of the five trials the reactor was contaminated with Bacillus megaterium.  相似文献   
34.
Fine monoclinic HfO2 powders were prepared from Hf metal chips by reaction with high-temperature high-pressure water. Dependence of the reaction on temperature-pressure-time was examined in both closed and open systems. Hydrothermal oxidation of Hf proceeded through three stages: the surface oxidation of Hf metal chips with H2O, the reaction of the Hf with released H2 to form hydrides, and the succeeding oxidation of the hydrides with H2O to form HfO2. Most of the fine HfO2 powders were, however, considered to be formed by the latter two reactions after the cracking and pulverizing of metal chips associated with hydriding. The difference in the reaction rates between the closed and open systems was explained by taking into account the fugacity relations of H2 and H2O in the respective systems.  相似文献   
35.
36.
Unidirectionally crystallized CaO-P2O5 glass-ceramics were produced by reheating glass rods between 450° and 580°C (glass transition temperature ∼500°C) under a temperature gradient of 30°C/cm. These glass-ceramics exhibit high bending strength (∼650MN/m2) and toughness. Sample preparation is described and compared with conventional unidirectional solidification of melts. The characteristic mechanical properties are discussed in terms of the texture of the glass-ceramics.  相似文献   
37.
In this study, a traction drive electric motor was designed with a new magnet‐free motor design technique where electromagnets are generated on a rotor by utilizing changes in the spatial second harmonic of the magnetic fields. To apply the proposed technique to electric motor design, balancing the rotor and stator magnetomotive force is important. This paper presents design methods for adjusting the rotor and stator magnetomotive forces. A test motor was designed with these design methods and evaluated using a motor bench. The analytical and measurement data indicated that the proposed motor performed comparably to magnet motors.  相似文献   
38.
This paper presents a new type of magnet‐free motor that has concentrated stator windings and rotor coils with a pair of diodes. The most important feature of this motor is that currents in the rotor coils can be generated by utilizing the changes in the spatial second harmonic of the magnetic fields due to the concentrated stator windings, which normally increase motor losses. A prototype of the motor was designed and fabricated, and its basic performance was evaluated. First, using simplified analytic models, we explain the mechanism of inducing currents in the rotor coils by the changes in the spatial second harmonic of the magnetic fields. Second, we compare the torque performance of the proposed motor and that of other types of motors including a magnet motor through finite‐element analyses. The analyzed data show that the proposed motor can possess greater torque/volume ratio than that of the other motors. Finally, using the measured data, we validate the mechanism of inducing currents in the rotor coils, and examine the torque and power characteristics of the motor.  相似文献   
39.
大长高比腔体内的混合流体行进波对流   总被引:2,自引:1,他引:2  
该文报告大长高比腔体(Г=46)中强非线性状态(ψ=-0.47)混合流体行进波对流图案的数值模拟结果。利用MAC法通过二维流体力学扰动方程组进行了数值模拟。获得了发生在对流发生点附近的线性Counter propagatingwave,出现在分叉图非线性分支上的均匀行进波和发生在分叉图saddle-node附近的局部行进波状态等三种行进波对流图案,并探讨了它们的稳定性。最后将数值模拟结果与实验结果进行了比较。  相似文献   
40.
We treat traffic control methods for the multimedia ATM LAN, in which two service classes are considered; one is for high-speed data transfer based on a fast reservation protocol (FRP service class) and the other is for the continuous bit rate (CBR) traffic such as motion video (CBR service class). Through an analytic method, the performance of the CBR service class traffic is shown to be heavily affected by the FRP service class traffic. Thus, we introduce a reserved bandwidth for the CBR service class to guarantee some appropriate level of performance for the CBR service class. With the reserved bandwidth for CBR service class, the performance of CBR service class can be preserved from being affected by the FRP class traffic load.  相似文献   
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