管无芯弯曲中塑性变形规律的研究

通过大量管材弯曲试验,分析了沿弯曲线的切向和管壁厚方向的应力应变状态,给出弯管内、外侧管壁厚变化量和切向应变的近似计算公式。在后续试验的基础上,逐步将修正公式适用于实际生产。同时,为管材弯曲成形机理研究作了相应的基础准备工作。     

Characterization of wet microalgal cells pretreated with steam for lipid extraction

Steam pretreatment was employed to disrupt microalgal cells for lipids extraction.Effects of steam pre-treatment on microstructure of microalgal cells were investigated through scanning electron microscopy(SEM) and transmission electron microscopy (TEM).Effect of treatment on lipid extraction was also stud-ied.Microalgal cell walls were distorted after steam pretreatment due to the hydrolysis of organic macro-molecules contained in cell wall.Maximum curvature was increased from 1.88 × 10-6 m-1 to 1.43 × 10-7 m-1 after treatment with the steam at 130 ℃.The fractal dimension of microalgal cells increased from 1.25 to 1.30 after pretreatment for 15 min,and further increased to 1.47 when the pre-treatment time was increased to 60 min.Increased steam pretreatment temperature and time enhanced the hydrolysis of organic macromolecules,and finally destroyed microalgal cell walls at pretreatment temperature of 130 ℃ and pretreatment time of 60 min.Lipid extracted from wet microalgal was signif-icantly increased (2.1-fold) after pretreatment.     

型材产生壁厚偏差的原因及解决方法

就型材生产过程中产生壁厚偏差的原因进行了分析，并就解决偏差的方法进行了探讨。     

Mo的替代对FeNbBCu软磁纳米晶合金磁谱的影响

本文研究了Fe82Nb7-xMoxB10Cu1(x=0,1,3,5）系列纲伙晶软磁合金中Mo的含量对磁导率谱（频率范围1kHz-1MHz)的影响，并用畴壁钉扎理论进行了解释，在磁谱中观测到随着Mo含量的增加，弛豫频率线性地上升，μ′随外加磁场幅度变化曲线表明其原因在于Mo的替代导致了钉扎场的增强。     

回转窑窑壁非稳态传热模型及窑皮厚度优化

烟气、料床、窑壁是回转窑传热过程的三要素,在确定这三要素之间传热量的基础上,建立了回转窑窑壁非稳态传热数学模型。对中铝河南分公司2号窑窑壁的非稳态传热过程进行了数值计算。结果表明:窑体旋转一周,烧成带窑壁内表面温度将在1 232~1 334℃变化,这易导致窑壁热疲劳破坏;窑皮越厚,窑壁的径向温度梯度越小,热应力越低;将烧成带窑皮厚度控制在252 mm,可使烧成带窑壁外表面温度维持在200℃。     

石油钻采阀门内壁热丝TIG堆焊

石油钻采专用阀门的使用有耐强腐蚀性要求，制造时需在内壁表层堆焊耐腐蚀材料。此类阀门具有质量大、形状特殊、焊接可达性差，焊接质量要求严格等特点；重点介绍了Fronius热丝TIG焊工艺和ETR全自动堆焊设备在阀门堆焊制造上的应用。     

高层住宅结构设计

主要介绍长沙梦泽园高层住宅从基础到上部楼层各部位的结构设计,以及在设计、施工过程中所考虑的一些问题及处理方法。     

Electrodiffusion diagnostics of the flow and mass transfer inside a network of crossing minichannels

The global mass transfer and the local flow structure inside a set of crossing minichannels were characterized using the electrodiffusion method. The individual square-cross channel sections (a = 1.5 mm in sides) intersect at right-angles in order to form the flow cell. An array of 39 circular platinum electrodes (0.25 mm in diameter) was flush-mounted into the wall of the flow cell to investigate the wall shear rate at different locations. This array of small sensors allowed characterization of longitudinal and lateral variations in wall shear rate across the flow cell, flow distribution at the inlet and outlet sections, transition between laminar and turbulent flow regimes, and flow behaviour at the channel crossings. The results of global wall mass transfer measurements demonstrated that, from a mass transfer point of view, the flow cell exhibits similar behaviour to a porous medium.     

POWER CONSUMPTION WITH ANCHOR MIXERS EFFECT OF BOTTOM CLEARANCE

The effect of bottom clearance on power draw for anchors is investigated. The results suggest that power input decreases as the bottom clearance ratio b/D increases. A new correlation is proposed in which both bottom and wall clearance effects on power input are considered. The dependence of power input on these effects is additive rather than multiplicative. Thus, the total power consumption is the sum of the power inputs generated by the wall and bottom clearance. Power results from 3D-CFD numerical simulations are also presented. These results confirm fairly well the experimental points.     

金属闪光外墙乳胶漆的研制及性能研究

以丙烯酸酯及有机硅单体为原料合成了核-壳型硅丙乳液,用自制分散剂将闪光铝粉分散成水性闪光铝粉浆,并成功分散于硅丙乳液中,加入进口助剂,配制成水性金属闪光外墙乳胶漆.讨论了基料的玻璃化温度、单体的加入方式、引发剂、乳化剂、反应温度、聚合工艺和pH等对乳胶漆性能的影响.