基于改进自由体积和无规因子贡献的聚合物热力学模型

给出了一个基于改进的自由体积和无规因子的聚合物溶液热力学模型，其无规因子项(NRF)用来描述聚合物溶液中聚合物与溶剂的局部交互作用对剩余Gibbs自由能的贡献，改进的自由体积项(Entropic-FV)用来描述聚合物溶液的混合效应对剩余Gibbs自由能的贡献。文中对45组二元聚合物与溶剂体系进行了关联计算，并与Zafarani-Moattar模型，Flory-Huggins模型和UNIFAC-FV模型的计算结果进行了比较，其平均绝对误差分别为1．910％，2．465％，3．738％和10．149％。     

复合材料夹层结构产品固化变形分析

本文讨论产生复合材料产品固化变形的主要原因是树脂收缩引起的各方向上不同的线膨胀系数具体分析了复合材料夹层结构的的固化变形，经技术上的改进解决了固化变形，以满足产品的设计要求。     

森林植被改善对鄱阳湖流域径流和输沙过程的影响

以河流基流为切入点,研究流域植被调节径流、水土保持等微观作用影响大中型河流湖泊径流过程和水沙过程宏观效应的机理。鄱阳湖流域60年来天然降水没有发生趋势性变化。流域森林覆盖率由34.73%上升到63.00%,植被质量改善,赣江等入湖河流基流增加83 m~3/s,河流输沙量减少。2000年以后和2000年以前相比较,枯水期降水径流系数增大,年流量过程平坦化,一定程度上减小洪灾风险,有利于水资源利用和生态环境保护。2001年以后进入鄱阳湖泥沙平均每年减少1 007×10~4t;出湖泥沙增加314×10~4t。因此,鄱阳湖入江水道由淤积转变为冲刷,但出湖流量过程没有趋势性变化。     

分光光度法测定微量表面活性剂在油/水体系中的分配系数

测定微量阴离子表面活性剂浓度的分光光度法被推广到测定油相中的微量阴离子表面活性剂浓度,进而用于表面活性剂在油/水体系中分配系数的测定.两种情形下氯仿层的吸光度只取决于测量体系中自由阳离子表面活性剂的浓度,因此可用单一阳离子的标准曲线作工作方程.用该法测定油相和水相中的阴离子表面活性剂浓度,工作方程斜率不同,测量下限分别可达2.5×10-5 mol·L-1和1×10-6mol·L-1.     

低温快烧无铅精陶釉的研制

采用高温熔融法制备了适用精陶的低温无铅熔块，并应用热膨胀分析仪、SEM等方法研究了精陶釉的光泽度、热稳定性、热膨胀系数等性能。结果表明：采用Li2O，SrO，B2O3等复合熔剂，可以制备出光泽度高，热稳定好，坯釉膨胀系数匹配，结合良好，适于低温快烧工艺的无铅精陶釉。     

Delay time compensation based on coefficient of restitution for collision hybrid motion simulator

A hybrid motion simulator embeds a hardware experiment in a numerical simulation loop. However, it is often subjected to the inherent problem of an energy increase in the collision of two pieces of hardware in a loop because of the delay time. This paper proposes a delay time compensation method based on contact dynamics model for a collision hybrid motion simulator under delay time and establishes a compensation method for coupled translational and rotational motion. The model developed in this paper describes linear uniform motion of a floating object during the period of the delay time until the force and torque are observed and non-linear motion according to environmental stiffness after the initial delay time period in contact. By using the above model, compensation parameters are designed based on desired coefficient of restitution with iterative calculation. The proposed method achieves accurate delay time compensation and simultaneously realizes a variable desired coefficient of restitution over a wide range of frequencies. Furthermore, the compensation method for multi-dimensional motion is established under the assumption that the friction effect is very small. The efficiency of the proposed method is verified through collision experiments for the coupled motion in two dimensions.     

A PRACTICAL METHOD FOR RECTIFYING INTERFACIAL TENSION DATA TO PREDICT THE SHAPE OF INTERFACES IN AN IMMISCIBLE LIQUID/LIQUID/GAS SYSTEM

The shape of interfaces formed by the contact of two liquid phases, immiscible with each other, and a gaseous phase can be predicted on the condition that the tension to work at each interface is known with a sufficient accuracy. In general, interfacial tension data available are not so accurate, however, as to be useful as they are in predicting the shape of interfaces, particularly when the spreading coefficient of either liquid (liquid 1) on the other (liquid 2) has a negative value of a small magnitude. Presented in this note is a simple method to rectify the interfacial tension data, with the aid of a measurement of the radius of a lens of liquid 1 of a known volume placed on the horizontal surface of liquid 2, and thereby make them usable for predicting interfacial geometries. The method is tested by applying it to benzene/water and n-pentane/water systems.     

热处理制度对高ZnO含量的Li2O-Al2O3-SiO2系统玻璃析晶及热膨胀系数的影响

以TiO2 ZrO2 P2O5为复合成核剂,采用传统熔融冷却法获得了高ZnO含量的Li2O-A l2O3-SiO2系统的基础玻璃。通过差热分析确定了该玻璃的热处理条件、晶化性能,利用梯温炉实验、X射线衍射分析和扫描电镜对晶化试样的物相和微观结构进行了研究,讨论了热处理制度对玻璃的析晶及热膨胀系数的影响。研究结果表明:含10%(质量分数)ZnO的LAS系统样品玻璃最佳核化温度为(710±2)℃,玻璃的晶化活化能E为(275±2)kJ/mol,晶化指数n为3.11±0.2,样品玻璃在较低温度下失透,并且随着晶化温度升高,样品的热膨胀系数加大。     

工艺因素影响焦炭颗粒耐压强度的试验研究

焦炭颗粒的耐压强度一直是焦炭颗粒最重要的性质之一。利用最近提出的表征焦炭颗粒耐压强度的新方法，就模压压力、加压方式、粒度组成范围、粒度大小、粒度配比等因素对单粒度或多粒度组成焦炭颗粒耐压 强度的影响进行了较为详细的试验研究。结果表明：（1）焦炭颗粒的粒度大小和粒度范围均可用其原始平均细度来表征。焦炭颗粒的原始平均细度越大，其耐压强度系数也就越高；（2）多粒度组成焦炭颗粒混合料的耐压能力比单粒度组成混合料的耐压能力要高得多。对多粒度组成焦炭颗粒而言，模压压力及粒度组成配比对其耐压强度系数的影响不甚明显；（3）分阶段缓慢加压到位比一次快速加压到位有利于提高焦炭颗粒的耐压强度系数。