Physicochemical characteristics,antioxidant capacity and thermodynamic properties of purple-fleshed potatos dried by radio frequency energy

Abstract

The impacts of using radio frequency (RF) energy to dry purple-fleshed potatoes were investigated and compared to infrared radiation (IR) and microwave (MW) drying techniques. The gelatinization rate, color, flavor, morphological, and structural characteristics, thermodynamic properties, as well as antioxidant capacity were examined. The results indicated that the drying time of RF (70?min) and MW (21?min) were shorter than IR (105?min). The gelatinization ratio of MW, RF, and IR were 94.4?±?2.0, 88.3?±?1.4, and 64.5?±?1.1%, respectively. The degree of crystallization of purple-fleshed potato powder decreased with all three drying methods. RF-dried potatoes were able to retain higher polyphenols (loss rate: 4.3%), total anthocyanin (3.7%), and total flavonoid content (35.1%), whereas IR showed the lowest retention. The content of polyphenols also decreased significantly. Furthermore, after RF heating, the scavenging of free radicals was higher compared to MW and IR.     

Preparation and polymerization of isopimaric acid derivatives

Isopimaric acid is a typical rosin compound and can account for 30% of the total mass of slash pine rosin. The molecular structure of isopimaric acid derivatives features an unsaturated double bond at the C13 position, opening up the possibility of their industrial polymerization. In this study, isopimaric acid (95.4%), methyl isopimarate (99.5%), and allyl isopimarate (95.1%) were prepared as highly pure monomers. New experimental results are presented and mechanisms based on the investigation of free-radical polymerization under UV irradiation are proposed. New rosin monomers for potential value-added utilization of woody biomass are also identified. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47817.     

核反应堆加热流道含汽量计算研究

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不清根手工双面焊材料及工艺研究

本文分析了中厚板传统手工双面焊存在的诸如打底焊焊缝质量无法保证，需用碳弧气刨清根；工人劳动强度大；生产效率低；焊接质量不稳定等主要问题。为提高打底焊焊道质量，不用清根使背面得到良好的凹成形，研制了适合Ｘ形坡口的梯形体陶瓷衬垫。探讨了焊缝背面成形的主要影响因素及控制方法。     

发射药包装用复合纸桶现状与国内外纸桶对比

火炸药是易燃、易爆的产品，所以，它对包装要求也是很高的，特别强调它的包装可靠性。近几年来发展上许多国家都采用复合纸桶包装发射药，我厂生产的复合纸要能与国内外纤维板圆桶对比，在技术质量方面都比较先进。     

导弹动力系统操作训练虚拟仿真器的设计

根据日常训练的需要。设计了导弹动力系统操作训练虚拟仿真器。在深入分析操作规程的基础上，建立该仿真器基于HLA的分布式仿真结构。并对联邦成员内部的仿真逻辑、三维实体建模，基于数据手套和空间方位跟踪仪的人机交互等关键技术进行了研究。     

无线电引信贮存可靠性研究

研究了无线电引信电子系统的贮存可靠性问题，深入分析了无线电引信的电子系统的失效模式和失效规律，探讨了用引战配合效率的改变来描述无线电引信的失效规律的方法，并提出了预防无线电引信失效的措施。     

用熔融还原的方法从浸钒渣中提镓——碳饱和情况下的熔融还原过程

用通用旋转组合设计的方法得到了浸钒渣在饱和碳的熔融还原过程中镓的还原提取率与温度,时间及CaO的加入量关系的非线性数学模型。用非线性优化的方法并综合考虑Fe,Mn的回收,得到了最优的工艺条件及结果;用Langmuir—Knudsen方程推算了镓在铁液中的理论挥发量与时间的关系,与由本模型得到的关系式是一致的。     

Fe—Ga—O系平衡测定

在钼丝炉内氩气保护下，利用固体电解质定氧探头测定了含镓１．８７％～６．２１％范围内Ｆｅ－Ｇａ－Ｏ三元系平衡时的氧活度，通过处理得到镓在铁液中的标准溶解自由能等热力学参数与温度的关系。