共查询到19条相似文献,搜索用时 524 毫秒
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含水薄层多孔介质的微波干燥处理是实现长期保存的有效方法之一。本文推导了微波干燥含水薄层介质过程中温度梯度与含水率变化的关系,可以适用于多种不同材质的含水薄层多孔介质;利用多物理场仿真软件,建立了电磁场、温度场及速度场的耦合模型,仿真了薄层多孔介质在微波干燥过程中温度梯度与含水率变化的关联关系。选取黄豆作为薄层多孔介质样本进行微波干燥的实验,测量其在微波干燥过程中温度梯度变化和含水率变化的关系及不同干燥阶段对黄豆发芽率的影响。实验结果表明黄豆在微波干燥过程中,温度梯度与干燥程度存在固定关系,通过控制梯度趋于0时的干燥时间可以达到设定的干燥程度,并且对其发芽率影响较小。 相似文献
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一种封闭式零件清洗后的干燥方法,以燃气为主要能源的旋转式干燥炉进行脱水干燥,对干燥炉的设计方案、机械结构和自动控制做了详尽的论述。 相似文献
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几种新鲜生物样品的环境扫描电镜观察 总被引:1,自引:0,他引:1
应用常规高真空扫描电镜观察生物样品必须经过干燥和导电处理,但无论是采用冷冻干燥还是临界点干燥,多少都存在着一个样品缩水问题,有的生物材料如真菌菌丝和孢子、水生藻类、培养细胞、昆虫胚胎及幼虫等经处理后会产生较大的变形,无法观察到生物体的原来面貌。 相似文献
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在锗加工工艺中,干燥技术对于加工的成品率和抛光片表面质量有着重要的影响。介绍了异丙醇脱水干燥技术的原理,分析了异丙醇脱水技术对超薄锗抛光片的适用性。采用湿法清洗技术,有效去除了表面沾污和抛光后的表面氧化产物,控制了抛光片表面GeO_2的生成。采用异丙醇脱水技术成功实现了140μm厚锗抛光片的干燥。 相似文献
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植物材料干燥法比较及其在分类中的意义 总被引:2,自引:0,他引:2
应用扫描电镜观察植物材料的微形态特征是植物分类学研究中的主要手段。 植物叶片微形态特征保存的好坏,与其所用的干燥方法有密切关系;同时,微形态特征在植物分类运用中也是至关重要的。本实验采用六甲基二硅胺烷干燥法,单固定(戊二醛)微波辐射临界点干燥法,单固定(戊二醛)临界点干燥法及双固定(戊二醛、我酸)临界点干燥法,对数十种植物叶片进行了干燥处理并用扫描电镜对其观察比较。经多次试验结果表明:单固定(戊二 相似文献
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《Mechatronics》2016
Agricultural products such as chilies generally require drying for preservation. Traditionally, the chili drying process has been accomplished by burning fossil fuels in ovens or by open air drying. However, this process leads to severe losses in the quality and quantity of the final product. In this paper, a portable laboratory has been designed, developed and controlled using a mechatronic design philosophy in order to facilitate the chili drying process study. This portable laboratory can simulate different drying conditions under a controlled environment in order to find the best drying parameters for different kinds of chilies. Their computer based intelligence can monitor and control temperature, humidity, air flow, electric current and weight through a graphical user interface (GUI). The modeling and control technique of the system is described in detail. Simulation results using the mathematical model and experimental results under different drying conditions are presented to demonstrate the high performance of the portable laboratory and its great potential. 相似文献
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气介超声可在常温下去除水分,对干燥热敏性水果有突出优势。该文利用有限元仿真软件和实验研究了气介超声在干燥过程产生的微流现象,分析了气介超声对苹果片微观结构的影响,以及在干燥过程中超声功率对水果含水率的影响。结果表明,气介超声干燥后的苹果组织孔隙显著增大,这将有利于苹果内部的水分扩散,同时气介超声能更好地维持样品的微观结构,与未加超声作用的苹果片相比,气介超声处理后的苹果片含水率显著降低,且干燥速率能在短时间内得到迅速提升。上述结果对理解气介超声干燥机制有参考价值。 相似文献
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隧道式微波设备在干燥过程中存在物料温度不均匀的问题.本文采用在现有隧道式微波干燥设备中增加热风机,结合热风干燥温度均匀的优势,选用生物质颗粒作为研究对象,将热风干燥技术和微波干燥技术联合使用,从而改善微波设备干燥不均匀的现象. 相似文献
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Mark Shaw Venkatesh Meda Lope Tabil Anthony Opoku 《The Journal of microwave power and electromagnetic energy》2007,41(2):59-68
Heat sensitive properties (aromatic, medicinal, color) provide herbs and spices with their high market value. In order to prevent extreme loss of heat sensitive properties when drying herbs, they are normally dried at low temperatures for longer periods of time to preserve these sensory properties. High energy consumption often results from drying herbs over a long period. Coriander (Coriandrum sativum L., Umbelliferae) was dehydrated in two different drying units (thin layer convection and microwave dryers) in order to compare the drying and final product quality (color) characteristics. Microwave drying of the coriander foliage was faster than convective drying. The entire drying process took place in the falling rate period for both microwave and convective dried samples. The drying rate for the microwave dried samples ranged from 42.3 to 48.2% db/min and that of the convective dried samples ranged from 7.1 to 12.5% db/min. The fresh sample color had the lowest L value at 26.83 with higher L values for all dried samples. The results show that convective thin layer dried coriander samples exhibited a significantly greater color change than microwave dried coriander samples. The color change index values for the microwave dried samples ranged from 2.67 to 3.27 and that of the convective dried samples varied from 4.59 to 6.58. 相似文献