大学生求学满意度实证研究--某高校学生个体特征对满意度单项要素的影响分析

求学满意度，又称为求学满意程度，它取决于教育需求主体对教育服务的预期同其实际所感知的教育服务水平的对比。教学计划、教学组织、教师教学、教学设施、校园环境、学生5知识技能等都是影响求学满意度的因素。本文在调查取得基本数据的基础上，使用相关的统计检验方法，分析了性别、生源地和不同年级这些学生个体地征对求学满意度单项要素的影响。主要结论有：学生性别差异对满意度单项要素的影响基本是随机的；不同生源地的学生对教学计划和管理制度两个要素的评价具有差异；不同年级的学生对教学设施和知识掌握程度的评价具有显著性差异；学生对学校服务评价单项因素差异很少，总体满意度在一定程度上反应学校的实际情况。     

应用BP神经网络的单机架可逆式冷轧机弯辊力预设定

针对单机架可逆式冷轧机生产过程中，由于不同热轧生产厂的热轧板形原料性能、板形差别较大、从而造成弯辊力预设定值和实际指标相差较大的问题，利用现场生产工艺数据丰富，采用人工智能BP神经网络的方法，通过大量数据输入进行训练，大大的提高了生产过程中弯辊力预设定值的准确性。     

DD3单晶镍基合金蠕变—疲劳及寿命预测

从应变范围区分法(SRP),应变能区分法(SEP)的有关概念出发,研究DD3单晶镍基合金拉—拉应力状态下的蠕变—疲劳性能和保持时间的影响,并对其进行了定量计算;同时,用应变能区分法的数值法(SEP—NCM)实现对拉—拉应力状态下蠕变—疲劳的寿命预测。     

Optical Investigation of the Effects of Substrate Orientation on Oxidation of Single Crystal β-NiAl

The residual stresses in -Al₂O₃ scales formed on high-purity FeCrAl and FeCrAlY during oxidation at 1200°C and subsequent cooling and reheating were studied using photostimulated luminescence spectroscopy. Systematic measurements of the stress in the oxide were made as a function of both alloy thickness and cooling rate and the development of stresses in the oxide scale during thermal cycling was investigated as a function of the temperature. Depending on the ratio of the alloy and oxide-scale thicknesses, substantial stress relaxation was observed to occur during cooling at a rate of 8 K/min. Compressive growth stresses of 1 GPa were determined by comparing the residual-stress measurements at room temperature with those calculated based on thermal-expansion mismatch. No significant differences in the growth stresses, the total residual stresses, or the stress relaxation during thermal cycling were observed between the oxides formed on the Y-doped and undoped FeCrAl samples. Stress relaxation is also shown to lead to the development of tensile stresses in the oxide scale under certain conditions, in particular, those associated with slow cooling followed by rapid heating.     

NiAl－Fe金属间化合物合金的正电子寿命谱

测量了塑性金属间化合物合金Ｎｉ（５０）Ａｌ（３０）Ｆｅ（２０），Ｎｉ（５０）Ａｌ（２０）Ｆｅ（３０）和Ｎｉ（６０）Ａｌ（２０）Ｆｅ（２０）单晶和多晶的正电子寿命谱．基于正电子寿命谱的特征参数引入了正电子双区域捕获模型，并讨论了这些合金微观结构与力学性能之间的关系．     

冷镦挤复合的连接成形工艺分析及模具设计

基于镦挤连接成形的金属塑性变形规律,分析了一次连接成形件的冷镦挤复合成形的形变特点和工艺特点,进行了冷镦挤一次连接成形工艺过程的可行性分析设计和模具设计,并得到了生产实践验证。     

基于单片机的PID温控系统在塑料挤出机中的应用

针对在塑料挤出过程中温度控制的重要性，介绍了一种新型的PID温度控制系统。该系统采用高性能单片机芯片，可以方便地对系统加热、冷却周期及PID的各个参数进行在线设定和修改，提高了塑料挤出机的温控精度。     

Simulation of Fe-Al compounds developed during single superphosphate manufacture

In order to analyse iron phosphate complexes and gel-like phases encountered in the single superphosphate process, experiments were performed with a free-Al, Fe apatite crystal of Durango from Mexico phosphate rock and sulfuric acid. Reaction products were studied by X-ray diffraction and surface analysis methods namely X-ray photoelectron spectroscopy and scanning electron microscopy. Results show that in a free Al, Fe-system, part of the Ca(H₂PO₄ )₂.H₂O (MCPM) forms before precipitation of any CaSO₄(CS) and gel-like phase such H₂SO₄.yH₃PO₄.xH₂O is formed. When iron is added, the precipitation rate of (CS) and (MCPM) increases and Fe₃(H₃O)H₈(PO₄)₆.6H₂O is formed. When Fe and Al are added, a gel-like phase is quickly formed with a molar ratio that changes with time and develops into crystalline compounds. The composition of this gel may be represented as a mixture of two phases: H₂SO₄.yH₃PO₄.xH₂O and a gel containing Al-Fe-Si.     

过磷酸钙折流混合器的改进

由于绿原化工有限公司过磷酸钙装置生产能力由 6 70 t/ d(实物量 )提高到 84 0 t/ d,折流混合器负荷增大 ,出现折流环磨损加快等问题。采用若干技改措施 :扩大折流环内径、改变折流混合器喷射方向、采用新材料制作折流环 ,使折流混合器能满足 84 0 t/ d过磷酸钙生产的需要     

高水头船闸一字闸门水动力特性数值模拟

针对某山区高水头船闸30 m淹没水深下一字闸门的水动力特性进行研究,借助FLUENT软件提供的Realizable k-ε紊流模型对门体启闭过程非恒定流场进行动态模拟,通过建立由二维平面混合网格纵向拉伸成的三维棱柱体网格,结合2.5D重构和弹性光顺动网格法,在降低网格数量、提高计算效率的同时,实现一字闸门启闭全过程三维流场模拟。引入VOF法对自由水面迭代求解,得到一字闸门启闭过程门前后水位差及动水阻力矩变化规律,将计算结果与模型试验进行比较,两者吻合较好。模拟计算发现:门底间隙对闸门运行整个阶段动水阻力矩均有影响,动水阻力矩峰值随门底间隙增大而变小。