常压空气冷等离子处理对陈小麦生理生化及面团糊化特性的影响

采用30 W的常压空气冷等离子(APCP)处理陈小麦,处理时间分别是0、14、18、22及26 min,分析了小麦生理生化及面团糊化特性指标的变化。结果表明,14~26 min冷等离子处理显著(P<0.05)降低小麦籽粒水滴接触角、发芽率及陈化指数,而籽粒破碎率和吸水率显著(P<0.05)增加。可溶蛋白及巯基的含量随等离子处理时间趋向于增加。深入分析面团糊化特性,与0 min处理比较,等离子处理时间加长,面团醒发时间趋于增加,稳定时间趋于减少;最大稠度、混合结束时扭矩、最小扭矩、最终扭矩均趋于减少,而糊化峰值扭矩和加热结束时扭矩趋于不变;C1峰值幅度明显减少,蛋白质网络弱化趋于减少,淀粉酶活性增大,淀粉回生程度趋于降低,对应蛋白网络弱化速率和糊化速率增大、蒸煮稳定速率趋于减少,破损淀粉则明显减少。APCP可能通过增大过氧化物酶和淀粉酶活性而提高陈小麦面团蛋白强度和面团稳定性。     

均匀设计法优选制备复方天麻滴丸的最佳工艺

目的研究制备复方天麻滴丸的最佳工艺.方法选用U9(94)进行均匀设计优选滴丸的制备工艺.以硬度、拖尾、粘连及综合结果为指标,考察基质与药物之比、PEG 4000与PEG 6000之比、料温(溶解药物基质的温度)及滴距(滴管口与冷却液面之间的距离)对制备滴丸的影响.结果最佳的工艺条件为:基质与药物的比例为7:1,PEG 4000与PEG 6000之比为1:5,料温96℃,滴距5 cm.结论均匀设计法是优化复方天麻滴丸制备工艺的有利工具.     

Kinetic study of the hydrolysis of two formate esters held in a single organic drop

The rising drop technique was used to study the kinetics of the alkaline hydrolysis of two formate esters; n-butylformate and iso-amylformate in toluene formed the organic phase, whilst aqueous sodium hydroxide was used as the continuous phase. The effects of ester and alkali concentrations on the rate of the hydrolysis were studied. The order of the reaction was found to change with respect to the concentration of both reactants. Cetyltrimethylammoniumbromide (CTAB) was used as a possible catalyst for this liquid–liquid hydrolysis. When CTAB was added to the aqueous phase, enhancement of reaction was observed, whilst its addition to the organic phase caused inhibition of the hydrolysis. It is suggested that the enhancement of the reaction is due to the interaction of micelles in proximity to the interface while the inhibition is probably due to chemical blocking of the interface by adsorbed molecules of ionized CTAB.     

增幅冲击下钢筋混凝土板的抗冲击性能

钢筋混凝土板在服役期间可能承受落物多角度连续撞击等多次冲击荷载作用,钢筋混凝土板抵抗多次冲击的能力、多次冲击作用下钢筋混凝土板的性能演化和剩余性能评估等问题至关重要,其中,多次冲击的加载制度是研究钢筋混凝土板抗冲击性能的重点。为研究多次冲击下钢筋混凝土板的抗冲击性能,利用落锤和摆锤试验研究钢筋混凝土板在增幅冲击下的抗冲击性能,获得钢筋混凝土板在历次冲击过程中的冲击力时程曲线以及历次冲击后的整体变形和凹陷变形特征,分析钢筋混凝土板的吸能特性和累计损伤演化规律,研究钢筋混凝土板受冲击后的残余性能。结果表明：冲击角度对钢筋混凝土板的变形有显著影响,斜向冲击对钢筋混凝土板安全性能的影响更大;增幅冲击降低钢筋混凝土板的吸能能力,提高其破坏率,钢筋混凝土板的冲击响应相对于恒重重复冲击更加稳定。     

Spouting of two-dimensional beds with draft plates

Two slotted two-dimensional spouted bed units with flexible bed dimensions were used with draft plates to study spouting pressure drop and minimum spouting superficial velocity. The data were collected while varying slant angle, spout width, separation distance, length of bed, height of bed, and size of bed (geometrical similarity) using shelled corn, soybean, and wheat. The variables which affect the spouting pressure drop and air flow through the beds are discussed. Empirical correlations are developed following the principles of dimensional analysis and similitude. The developed correlations agree closely with the collected data.     

Research and development of advanced structured packing in a rotating packed bed

As the core component of the rotating packing bed, packing is a place for efficient gas–liquid mixing and mass transfer. In this paper, a 3D structured packing composed of a mesh structure and a support structure was designed. The mesh structure is a ring-shaped mesh surrounded by triangular meshes, which is stable in structure and can achieve a high degree of dispersion and aggregation of the liquid phase. The support structure is composed of ring-shaped structural units arranged at a certain a...     

半椭圆涡流发生器强化换热机理

对单列及双列方式排列的一种斜截半椭圆柱体涡流发生器,以稳态的气、水逆流换热方式为模型,用数值方法模拟了迎流攻角为0°～90°,雷诺数6 000～48 000范围内的传热特性。结果表明:涡流发生器可以诱导纵向涡与流向涡,起到强化传热的作用,纵向涡在强化传热中起主要作用。     

基于语义分割的DWTT断口图像识别和评定方法研究

对石油管材落锤撕裂断口进行评定,目前采用的方法主要通过游标卡尺等测量工具进行测量和计算,存在对工作人员经验要求高、主观因素影响大、不规则形貌判别困难和效率低等缺点。针对以上问题提出了一种具有空洞卷积的编解码器模型的管材断口图像语义分割方法,首先对采集好的试样断口进行脆性区域的数据集标记,然后利用标记好的数据集对DeepLabV3+网络模型进行训练,该模型可以有效地分割试样断口中的脆性区域。最后对管材试样断口评定的计算方法进行了基于像素级别的改进,在对实验结果进行分析和对比后表明,所提出的方法具有更高稳定性、高准确率和良好分割效果。