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81.
A model system consisting of a uniformly distributed sample of ground pork in conjunction with a nitrite containing curing solution was utilized to evaluate the formation of N-nitrosamines. Utilizing this system a wide variety of compounds were discovered to dramatically reduce the level of N-nitrosopyrrolidine (NPyr) formed during frying. Carbohydrates including the reducing sugars dextrose, ribose, lactose, and maltose, as well as liquid smoke preparations, were found to reduce NPyr levels by as much as 60%. In addition, when low levels of combinations of inhibitors glucose, liquid smoke, and α-tocopherol were incorporated, reductions in nitrosamine levels as great as 80% were observed in model systems as well as in pilot plant manufactured bacon.  相似文献   
82.
Myosin A and myosin B gels formed by heating exhibited similar binding abilities as measured by the breaking energy, but different physical properties. At equivalent concentrations, myosin A gels exhibited smaller values for the Young's modulus of elasticity and larger values for strain at the breaking point. It was inferred from the results of a simple model experiment that in sausage manufacture the physical properties of the heat set minced meat gel are of the myosin B type when no pyrophosphate is present, and similar to the myosin A type when pyrophosphate is added. In the latter case, the contribution of actin may be significant. The binding quality of the heat set myosin B gel increased with myosin concentration. Hence, the binding quality of sausage should be influenced by the myosin B content of meat.  相似文献   
83.
Crystalline fine powders of LiAlO2 can be prepared by hydrolysis of metal alkoxides for application to the breeder blanket in nuclear fusion. The precipitates were fine crystalline particles of β-LiAlO2of ∼0.1-μm size under controlled conditions. The transformation from β- to γ-phase was confirmed at temperatures between 700° and 750°C. The microstructure of a sintered body at 1000°C consisted of homogeneous fine particles and pores suitable for the blanket material. A fully dense sintered body could be prepared at 1400°C.  相似文献   
84.
85.
氮硫掺杂介孔TiO2薄膜结构及其光催化性能   总被引:1,自引:0,他引:1  
分别以Ti(OBun)4和Pluronic F127为无机前驱体和模板剂, 以硫脲为添加剂, 采用sol-gel法结合蒸发致自组装法(EISA)制备了锐钛矿结构的介孔TiO2薄膜材料.采用SEM、 XPS、N2 吸附-脱吸、XRD和 UV-Vis光谱对其进行了表征. 研究发现, 向前驱体溶液添加硫脲一方面改变了TiO2的介孔结构, 另一方面对介孔TiO2进行了N、S共掺杂. 当溶液中硫脲与Ti(OBun)4的摩尔比为2.5%时, 介孔TiO2的孔径由未掺杂的7.0nm增至12.4nm, 光催化降解甲基橙实验表明其在紫外光区具有最优的光催化活性; 当溶液中硫脲与Ti(OBun)4的摩尔比为5%时, 其吸收边由380nm扩展至520nm, 光催化降解罗丹明B实验表明其在可见光下显示出最优的光催化活性.  相似文献   
86.
Metallic materials are known to be very sensitive to Gallium (Ga) focused ion beam (FIB) processing. Crystal defects formed by FIB irradiation degrade the transmission electron microscope image quality, and it is difficult to distinguish original defects from FIB process-induced damage. A solution to this problem is the low acceleration voltage and low incident angle (LVLA) Argon ion milling, which can be incorporated as an extensional countermeasure for FIB damage removal and eventually for preparation of high-quality lamellae. The transmission electron microscope image quality of iron single crystal could be improved by removing crystal defects using the low acceleration voltage and low incident angle Argon ion milling finish. Lamella quality of the processing result was almost similar with that of the conventional electrolytic polishing. As a practical application of the process, low damage lamella of stainless cast steel could be prepared. Effectiveness of the FIB system equipped with the low acceleration voltage and low incident angle Argon ion milling function as a tool to make high-quality metallic material lamellae is illustrated.  相似文献   
87.
In this study, the lowest loss point is calculated using the permeance method when the machine parameters of the interior permanent magnet synchronous motor are changed. Using the proposed method, the motor loss is easily calculated compared to the conventional method. The periodic change in the magnetic resistance in the air‐gap according to the rotation of the rotor does not need to be considered because the magnetic equivalent circuits of the rotor and stator are separated. In this study, the motor loss is calculated by the proposed method and a finite element method (FEM). As a result, the error in the calculation results between the permeance method and the FEM is 2.9%. On the other hand, the motor losses are calculated by the permeance method when some machine parameters are changed. As a result, these results agree in principle with those of the FEM. Therefore, the validity of the proposed method is confirmed. In addition, the method for motor design is considered in terms of the loss.  相似文献   
88.
Recently, in Japan, large‐scale introduction of photovoltaics (PVs) has been under way. This development increases the likelihood of system voltage increase and fluctuations, which can be prevented by employing PV output prediction. In this study, we focus our attention on applying PV output prediction to system operation with the objective of system voltage control. In this paper, 30‐min ahead prediction is assumed according to prior research with prediction error consideration. System voltages of 30 min ahead are estimated and are controlled in advance by using transformer taps and static capacitors. In this paper, voltage control is proposed for coordinating control, which is based on one of the games in the game theory, potential game. The validity of the proposed method is confirmed by running simulations using a modified IEEE 30 bus system. By applying the proposed method, both the voltage deviations and control counts improved considerably compared to a conventional method.  相似文献   
89.
Fuel cells, as components of cogeneration systems and battery energy storage systems, can be used as power sources in an isolated power system in complex housing at times of blackout. This paper reports study results on such isolated power systems. Simulation models are developed and the results are compared with measured values of active power, reactive power, and voltage. Good agreement is obtained. In this analysis, it is found that there is a stability limit in such inverter power source operation. The stability limit is expressed by a short circuit power ratio that is similar to the one in conventional ac systems. Nonlinear load switching is also studied to demonstrate stable operation.  相似文献   
90.
In the disconnecting switch of 300 kV or less single pole structure, the Great East Japan Earthquake received much damage at the former by the rotation insulator base metal which damage experience had. Conventionally, we carried out a simple desk evaluation about earthquake‐proof evaluation of insulator base metal. However, there is deviation with the damage actual condition and it became clear that it was an apparatus weak point part. Then, we worked on the analysis accuracy improvement of insulator base metal, and we built the analysis technology of the single pole structured disconnecting switch.  相似文献   
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