阿拉伯胶对苹果膳食纤维挤压改性的影响

以苹果渣为原料提取苹果膳食纤维,利用单螺杆挤压机,添加阿拉伯胶进行共混挤压改性。结果表明,用此方法进行改性比单纯挤压改性效果更好,试验获得的改性最优工艺条件为:物料粒度60目,阿拉伯胶添加量为1%,螺杆转速为825r/min,静置时间为90min,加水量为20%。改性后苹果膳食纤维中水溶性膳食纤维含量达到27.7%,且其抗氧化能力和水合性质明显提高。     

过氧化氢氧化纤维素的研究

对过氧化氢为氧化剂制备氧化纤维素进行了研究,探讨了pH值、氧化反应时间、过氧化氢用量、催化剂Fe²⁺用量对纤维素氧化程度和降解程度的影响。研究表明,在浆浓1%,不加催化剂时,pH值为3,反应时间6 h,过氧化氢用量50%时得到的醛基含量为0.24 mmol/g和羧基含量为0.20 mmol/g,纸浆的平均聚合度为969;控制上述其他工艺条件不变,考察催化剂FeSO₄·7H₂O用量对纤维素氧化程度和降解程度的影响。实验结果表明,添加该催化剂后纸浆聚合度显著降低,最低降至611;在催化剂用量0.1%时,羧基含量达到最大值0.29 mmol/g;在催化剂用量0.6%时,醛基含量达到最大值0.42 mmol/g。     

变电站灭火系统应用探讨

模拟户外变压器火灾场景,进行了30余项次不同类型的变压器灭火系统灭火实验。通过变压器灭火实验现象和数据分析,阐述了变压器油和高压电缆的燃烧特性,比较了在带电距离、风速等外部因素的影响下,变压器各种灭火系统的灭火机理、灭火喷射强度、灭火效能的作用差异,重点介绍了地方规程中有关变压器灭火系统编写的亮点和创新内容。     

芜湖市计划建过江隧道

<正>从安徽省发改委获悉,安徽省芜湖将率先计划建设过江隧道,该项目起点位于鸠江区二坝镇规划纬一路,终点接弋江区大工山路,全长6.5km,隧道长度4 890m。目前该项目建议书已上报国家发改委,同时,按照时间进度表,2014年5月份将完成一系列批复手续,预计2014年12月份可以开工建设。     

复合材料风电叶片细观失效准则及其损伤演化

针对复合材料风电叶片在实际使用过程常常出现损伤的问题,提出一种基于细观失效准则的复合材料细观损伤分析模型。采用通用单胞模型(Generalized method of cells,GMC)对具有周期性的单向复合材料层合板进行细观建模,并且引入基于Huang模型的细观失效准则和刚度退化准则,从细观层面上分别对纤维和基体的失效模式进行表征,对4种单向复合材料层合板的渐进损伤过程进行数值模拟。在试验验证过程中,先对两种不同状态(含损伤和无损伤)的复合材料风电叶片进行了静力加载试验,采用光纤光栅传感器监测损伤对风电叶片应变的影响;然后通过典型的单向层合板的拉伸破坏试验得到的应变曲线来验证本算法的有效性。结果表明:当复合材料风电叶片中存在损伤时,将降低其承载能力,并且应变值变化明显,可以通过应变来监测叶片的健康状态;提出的模型能够通过得到的应变曲线准确地预测单向复合材料层合板的力学性能和破坏强度值。     

Visual focus of attention estimation based on improved hybrid incremental dynamic Bayesian network

In this paper, a visual focus of attention(VFOA) detection method based on the improved hybrid incremental dynamic Bayesian network(IHIDBN) constructed with the fusion of head, gaze and prediction sub-models is proposed aiming at solving the problem of the complexity and uncertainty in dynamic scenes. Firstly, gaze detection sub-model is improved based on the traditional human eye model to enhance the recognition rate and robustness for different subjects which are detected. Secondly, the related sub-models are described, and conditional probability is used to establish regression models respectively. Also an incremental learning method is used to dynamically update the parameters to improve adaptability of this model. The method has been evaluated on two public datasets and daily exper iments. The results show that the method proposed in this paper can effectively estimate VFOA from user, and it is robust to the free deflection of the head and distance change.     

Facial expression recognition based on improved completed local ternary patterns

The information of expression texture extracted by the completed local ternary patterns (CLTP) method is not accurate enough, which may cause low recognition rate. Therefore, an improved completed local ternary patterns (ICLTP) is proposed here. Firstly, the Scharr operator is used to calculate gradient magnitudes of images to enhance the detail of texture, which is beneficial to obtaining more accurate expression features. Secondly, two different neighborhoods of CLTP features are combined to obtain much information of facial expression. Finally, K nearest neighbor (KNN) and sparse representation classifier (SRC) are combined for classification and a 10-fold cross-validation method is tested in the JAFFE and CK+ databases. The results show that the ICLTP method can improve the recognition rate of facial expression and reduce the confusion between various expressions. Especially, the misrecognition rate of other six expressions recognized as neutral is reduced in the 7-class expression recognition.