基于BP网络的注塑件翘曲变形工艺参数优化研究

利用BP神经网络对注塑工艺参数及其相对应的翘曲变形量样本进行训练，得到了描述工艺参数到翘曲量映射关系的人工神经网络（ANN）模型；验证了此模型的准确性；得出了工艺参数与注塑件翘曲变形量的内在联系，为以后的参数优化以及翘曲量预测起到重要的指导作用。     

A SIMPLE METHOD FOR STUDYING THE KINETICS OF GAS-SOLID REACTIONS IN A FLUIDIZED BED REACTOR

A methodology for studying the kinetics of gas-solid reactions in a fluidized bed reactor is presented. This procedure is based on the analysis of the response of the system (flue gases) when batches of solids of different weight are added to the reactor. The method has been applied to the study of limestone particle calcination. The calcination rate constants obtained are in good agreement with those found in the literature. The method offers the advantage of simplicity and avoids the use of model assumptions or empirical correlations.     

模具对振动注射成型制件作用效应的初步研究

采用自制的振动试验台，分别安装两个不同的试样模具，使用了不同的聚合物材料，在不同的温度，压力下变化不同的振动频率和振幅进行实验，研究了聚合物熔体在振动场中注射成型时，成型模具对聚合物振动成型效应的作用。结果表明，模具浇口及型腔尺寸不同。振动注射制件的强度不同；模具型腔尺寸大振动产生的效应弱。型腔小振动产生的效应强。     

Thermal stability of NO 2 ⋅ and NO⋅ radicals formed in an Al23 catalyst during its preparation from a nitrate precursor

During the preparation of alumina as a catalyst support from aluminium nitrates by precipitation with a NH₄OH base, NO ₂ ^⋅ radicals have been formed in the catalyst after calcination under air in the solid at different temperatures. These radicals remained stable until a calcination temperature of 800°C. When the calcined catalyst was degassed under vacuum above 300 °C, the NO ₂ ^⋅ was reduced to give NO^⋅ and O^- species which were both tightly trapped in the solid. These latter species remained stable until vacuum treatment at 800 °C. This revised version was published online in July 2006 with corrections to the Cover Date.     

三峡工程泥沙问题研究60年回顾

对60 a来三峡工程泥沙问题研究的历程、主要研究结论作了简要综述。三峡水库初期蓄水运用以来的泥沙实测资料与预测对比分析表明:三峡水库上游来沙减少的趋势与初步设计阶段预测基本一致,但减少的进程有所提前;三峡水库泥沙淤积量远小于预测值;坝下游河床冲刷量与预测值基本一致,河床冲刷范围则大于预测;坝下游河床冲刷对防洪与航运的影响与预测基本一致;三峡工程泥沙问题总体上未超出论证与初步设计阶段的预测。在此基础上提出三峡工程正常运行期泥沙问题研究的建议,其中关于排沙调度方面,应按控制水库防洪库容年损失率小于1 000万m~3/a,以及变动回水区上、中段无累积性泥沙淤积的要求制定排沙调度方案,以长期发挥三峡工程的综合效益。     

Orientation and relaxation in uniaxially-stretched poly(2,6-dimethyl 1,4-phenylene oxide) — atactic polystyrene blends

Infra-red measurements of the dichroic ratio of atactic polystyrene and poly(2,6-dimethyl 1,4-phenylene oxide) absorption bands provide a valuable method for the determination of orientation as well as relaxation of chains of both polymers during stretching of their compatible blends. Influence of strain rate, temperature of stretching, and molecular weight of the polymers on orientation of both polymer chains in blends containing up to 35% PPO has been studied. Orientation relaxation for both polymers has been analysed using Lodge's constitutive equation. Master curves have been obtained for PPO and PS in the blends at a reference temperature T₀ = T_g + 10°C. Results are interpreted in terms of an hindrance of relaxation of PS chains induced by interaction with a highly-oriented PPO network which slowly relaxes.     

艾立许混捏机在炭阳极生产中的应用

在预焙阳极生产中，卧式连续混捏机曾经大量应用，使用效果良好。目前艾立许混捏机以其简化机械设计、降低维修及操作成本等许多独特的优点，在铝电解炭阳极生产中也得到大量应用。通过对原有卧式混捏机设备增加艾立许冷却系统，可以使两种设备得到最佳组合，可提高阳极质量，取得良好效益。     

基于FLO-2D的泥石流工程治理效果分析——以都江堰银洞子沟泥石流为例

选取地震区典型泥石流沟银洞子沟作为研究对象,运用FLO-2D软件再现该沟2013年泥石流发生过程,验证了通过研究区雨量数据获取泥石流流量线方法的可靠性以及相关模拟参数选取的合理性。在此基础上,基于泥石流发生频率和暴雨爆发频率相同的假设,对不同爆发频率下的泥石流工程治理效果进行了分析。结果表明:工程治理后,当爆发频率为30,50 a时,工程治理效果显著;当爆发频率为100 a时,工程治理效果不显著。因此,建议相关管理部门加强极端降雨条件下泥石流的预警和防治工作。     

基于转轮换型的水轮机增容改造及数值模拟

从青海铁吾电站HL160-WJ-84水轮机运行中的实际问题出发,在明确了水轮机改造的方向和目标后,对新旧型谱系列模型转轮的性能进行了对比分析。基于对比结果,初选出了D06A转轮用于技术改造试验。对改造前后的水轮机全流道进行三维湍流数值计算,给出了水轮机改造前后的水动力学特性差异。同时,对改造前后的水轮机蜗壳、转轮叶片的流态分布状况进行了分析比较,对改造后的水轮机整体水力性能进行预估。分析认为,对于小型卧式HL160机组而言,更换转轮后还需对上冠泄水孔实施改造,以防止对流场造成扰动,降低机组的效率。