制备纳米／聚合物复合材料时工艺参数的研究

用正交试验法对纳米粉体在聚合物中分散时的工艺参数——主机螺杆转速、加料螺杆转速（加料量）、机筒及机头温度、机头压力对混合效果的影响进行了研究。研究结果表明：影响HDPE／EVA／Nano-Mg（OH）2混合物力学性能的工艺条件的主次顺序为主机螺杆转速、加料螺杆转速、机头压力、机筒及机头温度。     

旋转式混合器内流场数值模拟及研究

通过对旋转式Kenics混合元件、间断螺纹混合元件和交错平板混合元件引入CFD数值模拟,比较了高黏度不可压缩流体在不同流量、转速、元件单元数、机筒间隙、长径比下三种旋转式混合器内的应变速率.结果表明,增大入口处流量和转动轴转速,增加元件单元数,减少混合元件与机筒间间隙以及长径比,都有利于提高混合器内的平均应变速率,增强混合效果,在相同条件下间断螺纹元件混合效果最好;不同结构的混合元件存在最优结构参数组合.     

不同结构单螺杆屏障混炼元件混合特性研究

运用有限元分析软件Polyflow对不同结构和不同螺杆转速下的修正Maddock混炼元件流场进行三维非等温数值模拟,得到了流场的压力、速度、温度和剪切速率的分布;利用粒子示踪法(PTA)对不同结构和不同螺杆转速的修正Maddock混炼元件流场内聚合物熔体所经历的混合过程进行模拟,并对结果进行了统计学分析;通过比较平均解聚功等参数对不同结构和不同螺杆转速下修正Maddock混炼元件的分散混合效果进行分析研究,并借助实验进行验证。结果表明,等腰反向型修正Maddock混炼元件对聚合物熔体的剪切作用和分散混合性能最好;适当提高螺杆转速可以有效地促进物料的分散混合。     

Kenics混合器混合性能的模拟研究

利用Fluent有限元分析软件计算了流体流过Kenics混合器过程中的应变速率,进而分析混合元件转速与旋转式Kenics混合器混合效率的关系,以及混合元件与机筒间隙对静态和旋转式Kenics混合器对混合效率的影响。模拟分析结果表明:旋转式Kenics混合器混合效率随转速增加而提高;减小混合元件与机筒间间隙有利于增加静态Kenics混合器混合效率,但间隙的减小对旋转式Kenics混合器混合效率的影响却很小。     

沟槽机筒单螺杆挤出机塑化特性的实验研究

采用剖分式机筒单螺杆挤出机实验平台,对熔融段沟槽机筒单螺杆挤出机塑化过程中熔融起始点、熔融长度、熔体温度/压力等塑化性能及产量进行了实验研究,比较了不同物料在不同工艺条件下对沟槽机筒单螺杆挤出机塑化特性的影响。结果表明,增大螺杆转速或提高机筒温度,塑化过程实际所需熔融长度增加,但对熔融起始点影响不大;熔融段机筒沟槽内熔体温度和熔体压力随螺杆转速增大无明显变化;随螺杆转速增大,沟槽机筒单螺杆挤出机挤出产量呈线性增加,表现出良好的挤出特性。     

双螺杆中啮合块、螺杆元件混合过程及混合性能的研究

以双螺杆挤出机中的啮合块、螺杆元件作为研究对象,对其混合过程及混合性能进行研究,分析物料与添加剂的相互运动及变化过程。利用网格重叠技术和Ployflow软件对啮合块、螺杆元件的混合性能进行仿真,研究螺杆元件及不同转速下啮合块对应流体区域内的最大剪切应力,粒子在流体区域内的停留时间分布、分布指数、分离尺度等。结果表明:在啮合块流道内的混合过程中,啮合区域的两种粒子进行分布混合,其他区域的粒子在轴向运动到第2片啮合块时开始被带入啮合区,与另一种粒子进行分布混合;在相同转速下,啮合块的混合性能优于螺杆元件,随着转速的提高,啮合块的分散混合性能逐渐增强。     

机筒温度和螺杆转速对木塑挤出温度场影响的模拟分析

建立了木塑挤出加工过程流场的准三维模型,考虑相变潜热和黏性耗散热的影响,利用FLUENT软件分别对模型(在改变机筒加热温度和螺杆转速的条件下)进行了稳态传热模拟。通过分析模型的温度和液态分数分布情况,得到了木塑材料在挤出加工过程中的熔融变化规律,确定了机筒温度和螺杆转速对木塑挤出过程的影响。研究结果表明,木塑挤出过程中最适宜的机筒温度为使物料完全熔融的最低温度;机筒温度不变时,螺杆转速增加会使物料熔融效果变差,通过提高机筒的加热温度可以得到较好的效果。     

固体推进剂同向双螺杆元件混合性能模拟

首先设计了4种固体推进剂用螺杆元件,并进行了固体推进剂药浆的流变性能测试,通过使用Polyflow软件对4种螺杆元件的流场进行数值模拟。对各螺杆元件流场的剪切速率、加权平均剪切应力、平均回流系数、累积停留时间分布等表征螺杆元件混合性能以及流场特性的指标进行分析,对比4种螺杆元件的分散和分布混合性能,并建立了螺杆元件混合性能的评价体系。结果表明,KB元件和S型元件对药浆有较好的综合混合性能,有利于固体推进剂的混合。     

低硬度EPDM/PP热塑性动态硫化胶Ⅱ.制备工艺条件对微观相态结构的影响

通过正交试验设计,研究了低硬度EPDM/PP共混型热塑性动态硫化胶的反应挤出动态硫化制备工艺,初步探讨了机筒温度、喂料螺杆驱动电压及主机螺杆转速等主要工艺因素对挤出物徽观相态结构的影响。     

低硬度EPDM—PP热塑性动态硫化胶II．制备工艺条件对微观相对态结构的影响

通过正交试验设计，研究了低硬度EPDM／PP共混型热塑性动态硫化胶的反应动态硫化制备工艺，初步探讨了机筒温度，喂料螺杆驱动电压及主机螺杆转速等主要工艺因素对挤出物微观相态结构的影响。     

底座连接口特征参数对显示器后壳注塑质量的影响分析

在Moldflow分析软件的基础上,对显示器后壳进行仿真研究,以翘曲变形量为质量指标,结合控制变量法进行单因素变动实验,保持注射工艺参数不变,研究显示器后壳底座连接口对制品翘曲变形的影响.对数据进行图表分析,结果表明显示器后壳尺寸定位68.58 cm(27英寸)时,底座连接口选用圆形,连接口位置距离底边26 mm,尺寸...     

The role of the symmetry and the flexibility of the anion on the characteristics of the nanostructures and the viscosities of ionic liquids☆

The transport properties of ionic liquids (ILs) are crucial properties in view of their applications in electrochem-ical devices. One of the most important advantages of ILs is that their chemical–physical properties and conse-quently their bulk performances can be well tuned by optimizing the chemical structures of their ions. This will require elucidating the structural features of the ions that fundamentally determine the characteristics of the nanostructures and the viscosities of ILs. Here we showed for the first time that the“rigidity”, the order, and the compactness of the three-dimensional ionic networks generated by the anions and the cation head groups determine the formation and the sizes of the nanostructures in the apolar domains of ILs. We also found that the properties of ionic networks are governed by the conformational flexibility and the symmetry of the anion and/or the cation head group. The thermal stability of the nanostructures of ILs was shown to be con-trolled by the sensitivity of the conformational equilibrium of the anion to the change of temperature. We showed that the viscosity of ILs is strongly related to the symmetry and the flexibility of the constitute ions rather than to the size of the nanostructures of ILs. Therefore, the characteristics of the nanostructures and the viscosities of ILs, especially the thermal stability of the nanostructures, can be fine-tuned by tailoring the symmetry and the conformational flexibility of the anion.     

浅谈设备的性能与操作对胎面压出质量的影响

简要介绍了胎面压出的工作原理及工艺过程，对设备的配置及操作对胎面压出质量的影响进行了分析，并对压出过程中常见的质量缺陷、造成的原因以及解决措施提出了自己的见解。     

Investigation of the effects of fatty acids on the compressive strength of the concrete and the grindability of the cement

In cement industry, a great energy consumption has been observed during grinding of clinker. To reduce this consumption, some waste products have been used as grinding aids.In this investigation, the effects of sunflower oil (SO), oleic acid (OA), stearic acid (SA), myristic acid (MA) and lauric acid (LA) on the fineness and strength of the cement have been examined. These aids were added into clinker in certain ratios based on the cement clinker weight and the grinding has been done for a definite time at the same condition.All of the fatty acids used increased the fineness as compared with the cement without the grinding additives. SO and OA decreased the strength significantly, LA decreased it to a lesser extent and SA increased it definitely according to the common cement. But MA did not alter the strength of the cement as much as SA. In addition, the covering of the balls influences the grinding of cement clinker unfavourably.     

煤粉流动性对GSP气化炉气力输送的影响研究

针对GSP气化装置煤粉气力输送在试车阶段出现的煤粉锁斗下料不畅、发料罐输送性能不佳等问题,从原料煤性质和工业装置的改进方面出发,通过煤粉的流动性参数的测量与研究,分析出现上述工程问题可能的内在原因,并提出工业装置改进方法,为保证GSP煤粉气力输送工业装置的正常运行提供解决办法。     

关于建立火炸药安全数据库的探讨

由反映火炸药及其制品的危险性能和用于对它们的生产、储运系统进行安全评价数学模型出发,探讨了如何建立一个全面、实用的火炸药安全评估数据库。通过对此数据库内容、数据表示方法、数据搜索方法以及建立步骤的讨论,明确了该数据库的使用对象和主要功能。     

The effect of the length of the oxyethylene chain on the conductivity of the polyurethaneurea electrolyte

Polyurethaneureas (PUU), which were synthesized from 4,4′-diphenylmethane diisocyanate (MDI), poly(ethylene glycol) (PEG), and 3,5-diaminobanzoic acid (DABA), were used as polyelectrolytes in this study. Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR) were used to monitor the effect of the various kinds of PEG on the changes in morphology of PUU electrolytes corresponding to the concentration of lithium perchlorate (LiClO₄) dopants. The results of DSC and FT-IR indicate the Li⁺ ions coordinate with the soft and hard segments. Additionally, the crystallinity of the PEG soft segment and the ordered hydrogen-bonded urea carbonyl groups decreased with increasing salt concentration. Impedance spectroscopy (IS) measurements show that the PUU electrolyte with the high phase separation degree has the high ionic conductivity. The hard-segment T_g and the soft-segment T_m influence the conductivity behavior of polyelectrolytes with increasing measurement temperature.     

Effect of the drafting force on the strength of the bottom of the spinneret

In spinning basalt fibres, the drafting force is in the same range as in spinning of glass fibres. The effect of the drafting force can not be considered in the calculation for the strength and rigidity of the bottom of the spinneret. __________ Translated from Khimicheskie Volokna, No. 5, pp. 47–50, September–October, 2007.