EFFECTS of DRYING TEMPERATURE and DESUGARIZATION ON GELATION CHARACTERISTICS of EGG WHITE SOLIDS

Liquid egg whites with and without desugarization were dried at temperatures of 50, 65, 80, and 95C. Gel samples of the egg white solids were prepared and their characteritics measured. Results indicated that the grel firmness decreased as drying temperature of egg white solids increased. Desugarized egg white solids has tower gel firmness readings than those of nondesugarized egg white solids. No gel formation were observed for egg white solids prepared at 95C.     

Detection of damage locations and damage steps in pile foundations using acoustic emissions with deep learning technology

The aim of this study is to propose a new detection method for determining the damage locations in pile foundations based on deep learning using acoustic emission data. First, the damage location is simulated using a back propagation neural network deep learning model with an acoustic emission data set acquired from pile hit experiments. In particular, the damage location is identified using two parameters: the pile location (P_L) and the distance from the pile cap (D_S). This study investigates the influences of various acoustic emission parameters, numbers of sensors, sensor installation locations, and the time difference on the prediction accuracy of P_L and D_S. In addition, correlations between the damage location and acoustic emission parameters are investigated. Second, the damage step condition is determined using a classification model with an acoustic emission data set acquired from uniaxial compressive strength experiments. Finally, a new damage detection and evaluation method for pile foundations is proposed. This new method is capable of continuously detecting and evaluating the damage of pile foundations in service.     

纯钛板成形极限曲线的预测（英文）

商业纯钛(CP Ti)由于其轻质,高比强度和优异的耐腐蚀性能而被广泛应用于板式换热器。然而,与汽车用钢和铝合金相比,关于CP Ti板的塑性变形特征和压制成形性的研究相对较少。本文研究与CP Ti板压制成形相关的应力-应变关系及其力学性能和硬化行为。结果表明,CP Ti板的真应力-真应变关系曲线符合Kim-Tuan硬化方程,而不是Voce和Swift模型。通过冲压试验验证CP Ti板的成形极限曲线(FLC)可作为压制成形性的标准,并可通过Hora改进的最大力准则来分析预测。通过Kim-Tuan硬化模型和合适的屈服函数预测的FLC与冲压试验的结果吻合良好。     

基于磁扰动状态下Q235钢应力梯度的无损表征

基于电磁学原理的铁磁性材料应力无损检测,在工程实际中具有广阔的应用前景.本文根据对增量磁导率概念新的理解,提出了一种铁磁性材料在低频交变强磁场周期磁化状态下的高频交变弱磁场扰动磁化作用方式.通过提取一个强磁场磁化周期内的平均增量磁导率,对四点弯曲装置加载Q235钢所产生的纯弯曲状态下的应力梯度及沿着深度分布的磁弹性能总量进行了磁学无损表征.通过两组不同实验参数设置下的平行实验,验证了所提出的测试方法可以有效地检测加载条件下试件内部应力梯度及沿着深度分布的磁弹性能总量.两组实验结果均具有一般性,表明该检测方法具有可行性,并且具有一定的工程实际应用价值.     

OXIDATION OF METHACROLEIN AND ISOMERIZATION OF n-BUTENE OVER HETEROPOLY COMPOUNDS

The various salts of 12-molybdophosphoric acid were used for the oxidation of methacrolein and the isomerization of n-butene. The structure of the heteropoly compounds was identified with the aid of infrared spectroscopy, x-ray diffraction, and thermal analysis. The catalytic activity, acidity, and the reaction rate for oxidation of methacrolein were determined by micro-reactor with gas chromatography. The oxidation rate was proportional to the partial pressure of methacrolein and independent of those of oxygen and steam. The catalytic activity of alkali and alkaline earth metal salts was inversely proportional to the electro-negativity of metal elements. It was also revealed that the acidity of catalysts was strongly correlated with the catalytic activities for the oxidation of methacrolein and the isomerization of n-butene.     

EXPERIMENTAL STUDY OF CHARACTERISTICS OF Pt/TiO2 CATALYST

Chemisorption of hydrogen, carbon monoxide, and oxygen on 2 wt% Pt/TiO₂ was investigated to determine a satisfactory method for measuring the platinum dispersion on titania. The reduction of Pt/TiO₂ at high temperature results in sharp decrease in hydrogen and carbon monoxide chemisorption capacities and catalytic activity which cannot be accounted for by metal sintering. Oxidation-reduction treatments restore the usual properties of the catalyst. The TPD spectrum of hydrogen on Pt/TiO₃ shifts to higher temperature upon reduction at high temperature and shifts again to its original position upon oxidation. Shift of TPD spectrum does not appear in other catalysts. Oxygen adsorption method is inaccurate to measure crystallite diameter of platinum because oxygen uptake is enhanced not only due to reduced nonstoichiometric oxide support but also to penetration of oxygen into bulk platinum. Hydrogen chemisorption method, however, is a satisfactory technique to measure the platinum dispersion only if the strong metal-support bonding has been destroyed completely. Sintering rate in oxygen is greater than that in hydrogen regardless of the nature of the supports, and sintering resistance of Pt/TiO₂ in hydrogen is much greater than that of other supported platinum catalysts whereas stability of the platinum in oxygen is not dependent on the supports. The influence of chlorine in the presence of oxygen on the redispersion phenomena is found to be very important.     

ANALYSES OF THE SIMULTANEOUS ABSORPTION OF TWO GASES WITH EXOTHERMIC REACTION

This study examines the effects of various parameters on the nonisothermal gas absorption. A pair of coupled irreversible and reversible (1, ) order exothermic chemical reactions are considered in this research. The film model is employed to describe the heat and mass transfer. The interfacial temperature rise and the enhancement factors are determined nonlinearly by Muller's method. The nonisothermal effects of gas absorption are presented as functions of the dimensionless group M^½ at given thermophysical properties and kinetic parameters. The analyses provide useful information for nonisothermal reactor design and modeling.     

几种间苯二酚甲醛粘合剂的应用比较

间苯二酚甲醛树脂是橡胶轮胎工业常用的钢丝帘线和聚酯帘线与橡胶之间的粘合剂,间苯二酚甲醛粘合剂树脂完全可以替代间苯二酚单体。本文选取了国外知名品牌的进口树脂和两个国内品牌的树脂,在实验室进行了树脂的化学组成、胶料性能以及和钢丝的粘合力等研究。结果表明,虽然国产树脂的化学成分与进口树脂不完全一样,但是基本上,可以满足粘合的要求,代替进口产品。     

不同硅烷偶联剂对填充胶料硫化反应的影响

研究了硅烷偶联剂对白炭黑填充胶料的硫化反应的影响,探讨了硅烷偶联剂种类和用量对胶料性能的影响。结果表明,在使用白炭黑的SBR胶料配方中加入硅烷偶联剂,可以促进胶料的硫化反应,缩短硫化时间,提高生产效率。在本文所采用的硅烷偶联剂中,Si69对胶料的硫化反应具有最大的促进作用,并促进胶料和填料之间形成了最强的相互作用。