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江苏典型农户农业生态系统能量分析 总被引:1,自引:0,他引:1
本文对实行家庭联产承包责任制后的典型农户农业生态系统进行了能量的投入产出分析,从能量的角度提出了该系统的基本特征,并在此基础上对整个农村的能量的合理流动作了分析和探讨。 相似文献
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Xiaofeng Ren Xun Wei Haile Ma Huiji Zhou Jingjing Guo Shuyun Mao An Hu 《Cereal Chemistry》2015,92(2):193-197
We investigated the effects of a dual‐frequency frequency‐sweeping ultrasound (DFFSU) treatment on the functional properties and structure of zein. The solubility of ultrasound‐treated zein proteins increased slightly but significantly as the treatment time increased. The results showed that the DFFSU treatment had an obvious influence on the mean particle size and the size distribution. A significant (P < 0.05) increase in the size of the particles with respect to time was observed after a sonication time of more than 20 min in zein solutions. Differential scanning calorimetry results showed that sonication alters the thermal behavior of zein. Circular dichroism spectra showed a small increase in the percentage of ordered structure elements within the protein molecule. After 60 min of ultrasonication, the percentage of α‐helix structures increased by 0.9%, whereas the percentage of β‐sheets and β‐turns decreased by 0.5%. Microstructural analyses by scanning electron microscopy showed that several microholes appeared in the zein following ultrasonic pretreatment. Under the conditions investigated in this study, DFFSU treatment was found to affect the studied functional properties of the zein protein. This technology could be used to obtain improved functional properties in some protein samples. 相似文献
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Rui Liu Yimin Wei Xiaolong Ren Yanan Xing Yingquan Zhang Bo Zhang 《Cereal Chemistry》2015,92(5):427-433
In this study, the effects of mixing process parameters (degree of vacuum, water addition, and mixing time under vacuum) on the cooking and sensory quality properties of Chinese white noodles were investigated by using one commercial‐scale noodle production line and one typical commercial wheat flour. Noodle appearance, firmness, elasticity, smoothness, and total quality scores were significantly improved as the degree of vacuum increased from 0 to 0.06 MPa, although lower sensory scores and larger cooking losses occurred when noodles were mixed at 0.08 MPa. Noodles with a water addition of 35% had the highest total score and the highest scores for each sensory factor. As mixing time increased, the sensory score of cooked noodles increased initially and then decreased. With a mixing time of 7 min, the sensory score was the highest and cooking loss was the lowest. The results of response surface methodology indicated that fresh noodle quality was most affected by the water addition, followed by vacuum degree. Added water was a more important source of variation for appearance, firmness, stickiness, smoothness, total score, and cooking loss than degree of vacuum and mixing time, whereas degree of vacuum was the predominant source of variation for color and elasticity. The interactions between the factors had little effect on sensory and cooking properties. The optimal mixing conditions were determined to be as follows: degree of vacuum, 0.06 MPa; added water, 35.6%; and mixing time, 7.25 min. Furthermore, vacuum mixing produced a more even, coherent, and closed microstructure for the sheeted dough than nonvacuum mixing. 相似文献
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以经过栽培的木耳菌棒为试验材料,在万能试验机上对不同含水率的菌棒试样进行剪切、压缩的力学性能试验。试验结果表明:含水率是影响菌棒剪切强度、抗压强度的重要自然因素。平均含水率分别为11.75%,21.16%,27.68%的菌棒其平均剪切强度分别为29.4k Pa、20k Pa、14.5k Pa。平均含水率分别为14.3%,24%的菌棒,其平均抗压强度分别为144.7k Pa、77.7k Pa。菌棒的含水率与剪切强度,抗压强度均呈幂指数关系。这些都为研制菌棒粉碎机械、选择粉碎参数提供了设计依据。 相似文献
959.
连续流粮食干燥过程是一个非线性大滞后多变量的过程,要精确控制粮食出口的终水分比较困难。本文设计一种新的连续流粮食干燥过程的控制方法,对连续流粮食干燥过程中的多个影响因素进行研究,分析粮食干燥自控系统在设计时所必须选择的可测干扰、数字变量、控制变量和被控变量等,并且提出基于自适应逆控制技术的连续流粮食干燥系统的离散化模型,主要针对工业控制对象中存在的时变和时滞问题,推导出该连续流粮食干燥控制系统的预测模型。通过实验对实际系统进行验证,结果证明本系统具有较好的鲁棒性和稳定性。 相似文献
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