预制体结构对炭／炭复合材料力学性能影响

四种用于制备炭／炭（C／C）复合材料的预制体，即1K发布叠层坯体（1#坯体），3K发布叠层坯体（4#坯体），发市 炭纸叠层坯体（2#坯体），特殊炭毡 发布叠层坯体（3#坯本），并探索了预制体结构对C／C复合材料力学性能影响．研究表明：用1#坯体制备的C／C复合材料弯曲强度最高，2#坏体制备的材料弯曲强度最低，随著炭纤维（CF）体积含量的增加，用四种坯体制备的材料弯曲强度增大。确定了弯曲强度的优化配方．     

金属/Al2O3基纳米复合材料研究最新进展

金属／Al2O3纳米复合材料在保持原有金属的功能特性时，还可以获得 很好的力学性能，是有良好发展前景的一种纳米复合材料。本文回顾了近年来金属／Al2O3基纳米复合材料在制备工艺，微观结构和力学性能，增韧强化机理方面的最新进展，并指出了今后的研究方向。     

纤维体积含量对炭／炭复合材料性能的影响

通过对不同纤维体积含量的炭／炭复合材料进行力学性能、导热、导电性能试验,分析了纤维体积含量对炭／炭复合材料性能的影响。初始坯体的纤维体积含量对炭／炭复合材料力学性能影响较大,导热、导电性能则与材料内部结构关联较大而与纤维体积含量的关系不大。预制坯体的纤维体积含量选为25％至30％为最好。     

纳米Al2O3/环氧树脂复合材料的制备及性能

在原位法制备纳米复合材料时，要使纳米粒子在树脂中分散均匀，必须首先获得稳定的单体悬浮体系。基于这一原理，本文通过对纳米Al2O3表面改性即选择合适的分散剂，获得稳定的纳米Al2O3/丙酮悬浮液，然后将环氧树脂溶解于其中，制得纳米Al2O3／环氧树脂复合材料。运用透射电子显微镜，观察了纳米Al2O3在环氧基体中的分散情况。分析并讨论了纳米Al2O3含量对该复合材料力学性能的影响。结果表明：利用稳定的悬浮体系能制得分散较为均匀的纳米复合材料，在纳米Al2O3含量为5％的情况下，纳米复合材料的力学性能达到最优。     

ZrO2和Ni复合掺杂对Al2O3陶瓷结构及性能的影响

利用非均相沉淀包覆-热还原工艺制备粒径分布均匀、表面光滑的球形Al2O3/ZrO2/Ni,Al2O3/Ni,Al2O3/ZrO2复合结构粉体,再经真空热压烧结得到相应的复合陶瓷.通过X射线衍射和扫描电镜对前躯体、热还原粉体及烧结陶瓷的成分及结构进行了表征,并对陶瓷的力学性能、介电常数进行了检测和分析.实验结果表明:金属Ni的引入抑制了Al2O3的致密化,细化了晶粒,强化了氧化铝晶界,使氧化铝发生穿晶断裂而起到增韧效果;ZrO2对Al2O3陶瓷致密化及细化晶粒作用不明显,但通过相变增韧或形成弱界面起到了较好的增韧作用;Al2O3/ZrO2/Ni复合材料的断裂韧性增加值并未高于Al2O3/Ni和Al2O3/ZrO2 2种复合材料断裂韧性增加值之和,但增强了空间电荷的极化,使复合材料具有较高的介电常数.     

选区激光烧结制备PS/Al2O3纳米复合材料的研究

试探性地利用选区激光烧结制备PS／Al2O3纳米复合材料，利用乳液聚合方法改性纳米Al2O3，并在相同工艺条件下对PS／Al2O3纳米复合材料成型粉末（NH1）与纯聚苯乙烯（PS）粉末选区激光烧结试样的力学性能进行了比较结果表明，NH1烧结试样（PS／Al2O3纳米复合材料）较纯PS的拉伸强度提高了2倍左右，最大值达到29．8MPa；缺口冲击强度提高了20％～50％，最大值达到10．5kJ／m^2；洛氏硬度仅增加约5％；并利用场发射扫描电子显微镜对试样的冲击断面进行了微观结构分析．发现纳米Al2O3经乳液聚合改性后在基体中分散良好，起到很好的增强增韧作用．     

Fe3Al/Al2O3复合材料的凝胶注模成型工艺研究

机械合金化法制备Fe3Al粉,用凝胶注模成型的方法制备Fe3Al/Al2O3复合材料.结果表明,用凝胶注模成型工艺制备出了Fe3Al/Al2O3复合材料,分散剂MN可以显著提高浆料的固相含量,固相含量对浆料流变性有重要影响,10% Fe3Al/Al2O3坯体的微观结构最均匀.     

激光功率对聚己内酯基人工骨支架的影响

采用羟基磷灰石(HAP)和聚己内酯(PCL)作为原料,将HAP/PCL按1∶9的质量比制备HAP/PCL复合材料,打印成型后,测量其力学性能并进行分析研究。结果表明,所制备复合材料可用于选择性激光烧结技术,其烧结制件具有生物相容性并有较高强度。     

PPC/纳米羟基磷灰石复合材料的制备及其性能研究

采用共混的方法制备了聚碳酸亚丙酯(PPC)/羟基磷灰石(HAP)复合材料,研究了HAP用量对于PPC/HAP复合材料断面形貌、力学性能、接触角和流变性能的影响。断面形貌分析结果表明,纯PPC材料属于韧性断裂,随着HAP用量的增加,PPC/HAP复合材料逐渐转变为脆性断裂;HAP在PPC基体中能够均匀分散,二者具有良好的界面相容性。力学性能测试结果表明,PPC/HAP复合材料的断裂强度和冲击强度随着HAP用量的增加逐渐提高,而断裂伸长率随着HAP用量的增加逐渐降低。PPC/HAP复合材料具有良好的亲水性,且亲水性与HAP的用量成正比。流变测试结果表明,PPC/HAP复合材料的表观黏度具有温度和剪切速率敏感性,且复合材料的表观黏度随着HAP用量的增加先提高后降低。     

Al2O3/LiTaO3陶瓷复合材料的制备与力学性能

采用氮气保护热压烧结工艺制备Al2O3/LiTaO3(简称ALT)陶瓷复合材料，系统研究了其微观组织和力学性能。ALT陶瓷复合材料的相对密度比烧结纯LiTaO3陶瓷的高得多，表明Al2O3起到烧结助剂的作用。TEM观察表明，Al2O3p分布均匀，两者结合紧密，界面上有非常微量的分解物。ALT陶瓷复合材料的力学性能均随Al2O3p含量的增加而提高，Al2O3p的体积分数为40％时，其各项力学性能都是最高。     

Effect of preparation conditions on the properties of microspheres prepared using an emulsion-solvent extraction process

Methylaluminoxane microspheres were prepared using a hydrocarbon-in-perfluorocarbon-emulsion solvent extraction process. The effect of the preparation conditions on the size of the microspheres was investigated. As expected, the size of the microspheres decreased with increasing stirring speed. At low surfactant concentrations the size of the microspheres was independent of the surfactant concentration. However, the size of the microspheres decreased as the surfactant concentration was further increased. The size of the microspheres was not only affected by the surfactant concentration but also by the volume ratio of the dispersed phase to the continuous phase. At a low volume ratio of the phases the effect of the surfactant on the size of the microspheres was larger than the effect of the increased volume ratio of the phases. At high volume ratios of the phases the effect of the volume ratio of phases on the size of the microspheres became more significant than the effect of the surfactant. A slow solidification increased the formation of non-spherical microspheres.     

安全阀在线调试中阀座有效面积的反算法

在研究安全阀在线调校原理和化工企业生产特点的基础上,解决了安全阀在线调试过程中起跳压力计算的难点,即阀座有效面积的计算。提出了两种较实用的阀座有效面积的计算方法。经过对安全阀实际调校的检验,证明这两种方法是高效、精确的计算方法。     

Polymers in Eastern Europe

The year 1989 marked the 30th anniversary of the establishment of the Division of Polymers and Composite Materials within the framework of the Institute of Chemical Physics of the USSR Academy of Sciences. The conference to commemorate this event was held October 19–21, 1989. The results obtained by the division for the last 30 years were discussed. The division was created in 1959 on the initiative of Academician N. N. Semyenov, later the director of the institute. First, Prof. A. M. Markevich was appointed the head of the division. From the early 1970s to the late 1980s the division was headed by Academician N. S. Enikolopov; in 1988 Prof. A. A. Berlin was elected in charge of the division. About 700 people, including 50 doctors of sciences and 250 candidates for doctor of science degrees are engaged in the work of the division at the present time.     

低温煤焦油简易加工酚钠抽提方案之研究

为了降低焦油加工时的酸硷耗量、简化加工过程,进行了酚钠抽提方案之研究。 试验中考察了硷液浓度及焦油馏份中的酚类含量对抽提效果之影响;逆流抽提时之最宜硷用量;饱和酚钠液稀释以析出溶解的酚类时所需之水量;以及抽余油及粗酚的物理化学性质等。 试验结果表明:酚钠抽提法不但耗硷量甚少（对每百公斤酚类只需苛性钠10—15公斤,而一般硷洗法则需用40—45公斤）。而且抽余油不需经酸洗或氧化精制等过程,即可做轻柴油使用,其氧化安定性较好。此外酚钠抽提有显著的脱硫及脱氮作用。 抽余油之发动机试验证明:做为轻柴油其使用性能在任何方面均不逊于其他简易加工方法所制得之产品。     

Increasing the efficiency of the extrusion process

The article presents constructional methods of increasing the efficiency of the polymer extrusion process. Increasing the efficiency of the polymer extrusion process consists in the increase of the flow rate of the processed polymer and the energy efficiency of polymer processing extruders and the decrease of the specific energy consumption and the pulsation of the flow rate and polymer pressure, as well as quality improvement of the received extrudate as a result of better homogenization of mechanical and thermal properties and polymer structure. Therefore, the improvement of the constructional solution of the screw and barrel of the extruder plasticating system was discussed. The improvement of the construction of the screw lies in using the active and passive grooved barrel section. Original constructional solutions of the active grooved section with both longitudinal and helical grooves were shown. The devices increasing the efficiency of the extrusion were also shown, which included a screen changer, a melt pump, and a static mixer. Appropriate conclusions were drawn. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers     

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.     

台阶式并行微通道内液液两相流流型及其转变机理

利用高速摄像仪研究了台阶式并行微通道内液液两相流流型及其转变机理。以甘油水为分散相、含3% Span 85的环己烷为连续相,观测到了滴状-滴状流、过渡-滴状流、喷射-过渡流和喷射-喷射流4种流型;以两相流量为坐标轴绘制了流型图,并获得了流型转变线;分析了流型的转变机理。考察了分散相黏度对流型及其转变的影响机制。随着分散相黏度的增大,流型转变线整体向下移动,滴状-滴状流区域变小,喷射-喷射流区域变大。最后,运用介尺度概念分析了并行微通道内液液两相流非均匀结构的动态效应。     

Viscose filtration (review)

Conclusion This review of the relevant literature showed that the mechanism of viscose filtration differs from the filtration processes for other solutions in that it is largely of the clogging type, i.e., it proceeds in the inside layers of the filter, the result being that the capillary system of the filter material undergoes a change with a rapid increase in the resistance in the filtration process as a consequence. The degree of clogging depends on the ratio between the size of the contaminating particles and the diameter of the pores of the filter screen.The method of filtration may undergo a change in the future. Filtration proceeds in accordance with more than one mechanism simultaneously. The filtration process can be accelerated by using auxiliary substances while the degree of purity of the viscose can be increased by filtration through a nonwoven material.Woven filter materials and the auxiliary substances used in viscose filtration, polyvinyl chloride powder and fine-cut modified fibres, entrap mainly the particles larger than 10 . Nonwoven materials give a higher degree of purification so that in the second stage of the process the viscose should be filtered through a high-bulk nonwoven material.The new methods of analysis involving a direct count of the particles make it possible to investigate the quality of the viscose and the nature of the particles in more precise detail and to decide the conditions of filtration accordingly. The methods are inadequate, however, for an analysis of the quality of the filtered viscose.Although the number of publications dealing with the filtration of viscose for production purposes is quite large, an analysis of the relevant literature shows that not enough research was done on filtration through auxiliary substances, and on the influence of the properties of the filter material and the ratio of the size of the contaminating particles to the diameter of the pores of the filter screen on the degree of viscose purification; information about the nature of the gel particles and the influence of their size and type on the physicomechanical properties of the fibre is limited.Translated from Khimicheskie Volokna, No. 3, pp. 33–38, May–June, 1978.     

Modeling of substrate consumption by a biofilm on the surface of a rotating partially submerged disk

A model for a rotating biological contactor is proposed. The model takes into account the influence of the submergence level and rotational speed of a disk on its capacity. The processing of a substrate is described by the Michaelis-Menten kinetics with allowance for the aerobic nature of the process. Mass transfer between an aqueous medium and a biofilm is taken into account by adding the diffusion resistances of both media. The model includes the consideration of the erosion of the biofilm due to the frictional stress on the surface of the biofilm that moves relative to water. The variability of the thickness of the biofilm along the radius of the disk is taken into account. At the given biokinetic parameters, the depth of the submergence of the disk and its rotational speed that are optimum for the capacity of the biofilter are found using numerical experimentation. Comparison of the results with the experimental data of other authors is performed.     

Features of the crystallization of molten oxides in continuous induction melting

Conclusions The processes of crystallization of the molten material in the bath of a cold crucible in induction melting were considered. It was shown that the factors influencing the texture of the piece are the rate of crystallization of the molten material and the length of time of it in the two-phase zone of the front of crystallization. A quantitative evaluation of the tendency of various molten materials toward crystallization was proposed. Recommendations were given on reducing the nonuniformity of the pieces by decreasing the depth of the molten bath.Translated from Ogneupory, No. 3, pp. 10–14, March, 1985.