Effect of superfine grinding on physicochemical and antioxidant properties of pomegranate peel

Pomegranate peel powders were prepared by superfine grinding, whose effects were investigated on the composition, functional and antioxidant properties of the pomegranate peel products. Fluidised bed jet milling technology was used to process superfine pomegranate peel powder. The physical–chemical properties of coarse powder A (D50 = 413.4 μm) and B (D50 = 197.1 μm), fine powder C (D50 = 142.6 μm) and D (D50 = 41.2 μm), superfine powder E (D50 = 7.68 μm) and raw material powder (RMP) (D50 = 352.2 μm) were investigated in this study. SEM images revealed the shape and surface morphology of six pomegranate peel powders. The physical determinations showed that the smaller the powder particle size was, the greater the surface area (from 0.214 to 1.597 m² g^?1) and bulk density (from 0.653 to 0.751 g mL^?1) were, the smaller the angles of repose (from 51.69° to 38.74°) and slide (from 48.32° to 34.18°) were. The water holding capacity (WHC), water‐solubility index (WSI), polyphenols and flavonoids release were significantly improved as the size of pomegranate peel particle decreased. The results of FTIR and UV indicated that grinding process would not influence chemical composition of pomegranate peel. Vitamin C (VC) and butylated hydroxytoluene (BHT) were used in DPPH scavenging activity determination, and DPPH scavenging activity was A < RMP < BHT < B < C < D < E < VC.     

Effect of Spark Plasma Sintering Temperature on Electrochemical Properties of La0.82Mg0.18Ni3.50Co0.15 Alloy

Electrochemical properties of La_(0. 82)Mg_(0. 18)Ni_(3. 50)Co_(0. 15) alloys synthesized by spark plasma sintering( SPS) were investigated based on the electrochemical measurements,physical parameters and microstructure observation. The sintering behavior of La_(0. 82)Mg_(0. 18)Ni_(3. 50)Co_(0. 15) alloys at the temperatures of 900,950 and 1 000 ℃ is characterized by four stages,i. e.,initial slight shrinkage,expansion,abrupt shrinkage and slight expansion. The maximum shrinkage displacement increases with increasing sintering temperature. All of the alloys consist of( La,Mg)_2( Ni,Co)_7 phase; additionally,temperatures of 900 and 950 ℃ are beneficial to the formation of( La,Mg)( Ni,Co)_3 phase,whereas the LaNi_5 phase is easy to form in the alloy synthesized by SPS at 1 000 ℃. The electrochemical measurements indicate an evident change of the electrochemical performance of the alloys associated with increasing the sintering temperature. The discharge capacity of the alloys first increases and then decreases as sintering temperature rises,whereas their cycle stability clearly grows all the time.Furthermore,the charging-discharging potential difference and discharging efficiency both demonstrate that the electrochemical properties of the alloy electrodes first augment and then decline with increasing sintering temperature.     

双组分聚氨酯道桥密封膏的研制

以聚醚多元醇、甲苯二异氰酸酯(TDI)、扩链剂、填料、复合催化剂、增塑剂、触变剂为主要原料,制备了一种低模量、高弹性、高粘接力的双组分聚氨酯道桥密封膏,讨论了影响该密封膏性能的因素.结果表明,当异氰酸酯指数在1.0～1.35、复合催化剂用量在0.9％ ～1.1％、触变剂用量为10％～12％、活性轻钙用量为18％ ～21...     

建筑防水层低温性能现场检测方法及实例分析

对建筑防水层低温性能现场检测方法进行了介绍,结合此方法的应用实例,分析讨论了建筑防水层的低温性能现场检测技术的准确性、应用价值和现实意义.     

油气减震支柱磨合试验台的机械原理设计

以油气减震支柱磨合试验的任务要求为输入,介绍了用减速机驱动平面四杆机构同时实现对两件产品进行磨合试验的设备的机械设计原理,该原理对其它相似产品试验台的机械设计有一定的借鉴和参考价值。     

凝固浴对PAN原丝性能的影响

在生产聚丙烯腈(PAN)炭纤维过程中,纺丝期间凝固浴的各种条件对纤维的成型和性能起着关键作用。本文介绍PAN高聚物在湿法一步法纺丝过程中二甲基亚砜(DMSO)凝固浴各种成型工艺条件对PAN原丝的结构、机械和物理性能的影响。     

气爆声源阵列的同步性故障分析

气爆声源阵列的性能在很大程度上决定于各气爆声源的同步性。其同步性误差会严重影响到气爆声源阵列的子波和频谱特性。根据气爆声源阵列同步性的相关标准,分析了造成气爆声源阵列同步性故障的主要影响因素,并针对这些故障提供了必要的解决方法。     

屏过中12Cr1MoVG与16Cr23Ni13的焊接工艺

我公司某产品的屏式过热器采用2Cr1MoVG的管子与16Cr23Ni13的扁钢相焊,由于两种材料在化学成分及物理性能上有很大的差异,在焊接时,选用合适的焊接工艺,以获得合格的焊缝接头,保证该屏过的高温运行性能。