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1.
《Journal of dairy science》2022,105(4):3176-3191
Milk concentrates are used in the manufacturing of dairy products such as yogurt and cheese or are processed into milk powder. Processes for the nonthermal separation of water and valuable milk ingredients are becoming increasingly widespread at farm level. The technical barriers to using farm-manufactured milk concentrate in dairies are minimal, hence the suspicion that the practice of on-farm raw milk concentration is still fairly uncommon for economic reasons. This study, therefore, set out to investigate farmers' potential willingness to adopt a raw milk concentration plant. The empirical analysis was based on discrete choice experiments with 75 German dairy farmers to identify preferences and the possible adoption of on-farm raw milk concentration. The results showed that, in particular, farmers who deemed the current milk price to be insufficient viewed on-farm concentration using membrane technology as an option for diversifying their milk sales. We found no indication that adoption would be impeded by a lack of trustworthy information on milk processing technologies or capital. 相似文献
2.
《Advanced Powder Technology》2022,33(11):103817
The heat production and thermal storage characteristics of rapid-preparation amorphous powder activated coke (RAC) were investigated. RAC was prepared by using a drop-tube reactor system. The natural oxidation characteristics of RAC were studied through combined TG–FTIR analysis and temperature-programmed experiment. Experimental results showed that CO and CO2 were the main oxidation products of RAC in air, and that the oxidation reaction was in accordance with the Arrhenius equation and law of mass action. Thermal storage characteristics were studied through computational fluid dynamics simulation. The maximum excess temperature θmax increases linearly with the increase of the initial temperature. The concentration fields of the products show that CO2 is mainly concentrated in the upper part of the coke bin, and the CO generated by CO2 at high temperature is mainly concentrated in the central part of the coke bin. 相似文献
3.
《Geotextiles and Geomembranes》2022,50(5):994-1003
Geogrid reinforcement can significantly improve the uplift bearing capacity of anchor plates. However, the failure mechanism of anchor plates in reinforced soil and the contribution of geogrids need further investigation. This paper presents an experimental study on the anchor uplift behavior in geogrid-reinforced soil using particle image velocimetry (PIV) and the high-resolution optical frequency domain reflectometry (OFDR). A series of model tests were performed to identify the relationship between the failure mechanism and various factors, such as anchor embedment ratio, number of geogrid layers, and their location. The test results indicate that soil deformation and the uplift resistance of anchor plates are substantially influenced by anchor embedment ratio and location of geogrids, whereas the number of geogrid layers has limited influence. In reinforced soil, increasing the embedment ratio greatly improves the ultimate bearing capacities of anchor plates and affects the interlock between the soil and geogrids. As the embedment depth increases, the failure surfaces gradually change from a vertical slip surface to a bulb-shaped surface that is limited within the soil. The strain monitoring data shows that the deformations of geogrids are symmetrical, and the peak strains of geogrids can characterize the reinforcing effects. 相似文献
4.
《Geotextiles and Geomembranes》2022,50(6):1083-1109
The paper investigates the feasibility of using fine-grained soil as backfill material of geosynthetic-reinforced walls and slopes, through a laboratory study on pullout behavior of geogrids in granular layers. A series of pullout tests was carried out on an HDPE uniaxial geogrid in thin sand and gravel layers that were embedded in clay specimens.Aside from different soil arrangements, the influences of moisture content and overburden pressure on the geogrid pullout behavior is assessed and discussed. The tests were carried out at four different gravimetric water contents (GWC) on the dry and wet sides of the clay optimum moisture content (OMC), and overburden pressure values within the range σv = 25–100 kPa. Particle Image Velocimetry (PIV) was used to capture digital images during the tests, which were processed to help with the interpretation and improved understanding of the soil-geogrid interactions at different GWC values. Results show that embedding geogrid reinforcement in layers of sand or gravel can significantly increase the pullout resistance in an otherwise moist clay backfill, and this improved pullout efficiency is greater at higher overburden pressures. The improvement in pullout capacity was observed in clay specimens compacted at both the dry and wet sides of the OMC. 相似文献
5.
水冷陶瓷增殖剂(WCCB)包层作为中国聚变工程试验堆(CFETR)候选包层之一,承担着氚增殖、核热提取、屏蔽等重要涉核功能,其中子学设计的可靠性直接影响CFETR氚自持目标的实现。为验证中子学设计工具,即MCNP和FNEDL3.0数据库,在WCCB包层中子学设计中的可靠性,基于研制出的WCCB包层模块,在DT中子环境下开展中子学实验,对以产氚率(TPR)为代表的中子学参数进行了模拟值(C)和实验值(E)对比分析。结果表明,模块中轴线位置处TPR的C/E为0.97?1.08,而模块边缘位置处TPR的C/E为0.65?0.82;模块钛酸锂层边缘区197Au(n,γ)198Au反应率的C/E为0.72?0.90,表明模块边缘区存在非期望的散射中子,导致该区TPR模拟值和实验值偏离较大。 相似文献
7.
教学行为分析作是教学质量分析的重要组成部分,也是教学引导与反馈机制的重要依据。文章阐述了人工智能(AI)的含义及发展历程,重点分析总结了教学行为分析方法及AI在教学行为分析上的应用。文章以东南大学电工电子在线实验为研究平台,探索分析了AI技术在实验教学行为分析上的可行性,梳理了基于专家系统的在线实验分析系统的设计思路,充分探讨了“智能”教育在实验教学中的深刻内涵。 相似文献
8.
通过粒子图像测速流场实验与传热实验相结合,研究了内插螺旋立式上行管的螺旋节距、丝径、中径比等结构参数在不同Re下对流场、阻力及传热性能的影响。结果表明,内插螺旋能够有效扰动和混合管内流体,使管内形成多个纵向旋涡的流体结构、增大管壁附近液体涡量,有利于强化传热。当Re相同时,管内平均流速v、Nu和综合换热性能PEC均随丝径增大而增大,随中径比减小而增大;随节距增大,3种参数均出现增大的趋势,节距大于20 mm后开始减小。管内流体的阻力f随丝径和节距增大而减小,随中径比增大而增大。综合比较,在较低Re时,节距p=20 mm、丝径e=1.6 mm、中径比D/d=0.75时综合传热效果最好。 相似文献
9.
10.
研制一种适合对各种液压孔口或缝隙进行高低温流体力学试验的新型试验装置,运用该装置对具有不同几何参数的液压阻尼孔进行在-50~80℃宽温度范围内的流动特性试验,研究以普通抗磨液压油HM46和低温抗凝减振器油TITAN SAF 5045为工质及其温度变化时对液压阻尼孔流量-压力特性曲线、幂指数和流量系数的影响,研究表明,在低温条件下,液压阻尼孔的流量系数均因油液黏度增大、流动性变差而呈线性下降的趋势,从宏观上看,HM46通过液压阻尼孔时的流动稳定性较差,其对应流量系数的下降幅度明显大于TITAN SAF 5045对应的下降幅度,厚壁小孔流量系数的下降幅度明显大于薄壁小孔对应的下降幅度。研究所获得的新型试验装置、试验数据分析方法和具体理论公式为深入研究和优化现代液压元件在宽温度范围内的动态性能提供新型试验平台与理论基础。 相似文献