三乙胺对丙烯酸酯-聚氨酯复合乳液的影响研究

采用原位乳液聚合法，合成聚氨酯-丙烯酸酯(PUA)复合乳液。通过粒径分析、黏度测定、力学测试等手段，研究了三乙胺对乳液性能和相行为变化等的影响。实验结果表明：随着中和度提高，乳液外观改善，贮存稳定性提高，吸水率增大，耐水性降低，拉伸剪切强度增大，而断裂伸长率降低，相转变点后延。     

干气密封在LPG装车泵上的应用

干气密封是一种用于高速旋转设备的非接触式密封。近年来随着技术发展,其制造成本降低,开始在低速离心泵上应用。液化石油气(简称LPG)装车泵因压力瞬变和环境影响而工况恶劣,造成该类泵密封使用寿命短,液化气泄漏严重。干气密封的应用彻底改变了装车泵的运行状况,同时大大改善了现场环境。     

国内聚羧酸系高性能减水剂的合成及研究状况

简述了聚羧酸类减水剂合成方法、分子结构与性能的关系,讨论了大单体聚乙二醇丙烯酸酯等的制备工艺技术。     

硫磺制酸废热回收系统蒸汽参数的选择

从火用和工程投资的角度对硫磺制酸装置废热回收系统的三种典型蒸汽参数(3.82 MPa、450 ℃,3.82 MPa、425 ℃和5.3 MPa、470 ℃)进行分析比较.结果表明,具有5.3 MPa、470 ℃次高压参数的蒸汽火用值最高,即做功能力最大;虽然其热回收系统的投资较高,但因发电容量较大,所增加的投资回收期很短,所以综合优势较好.建议在大型硫磺制酸装置中尽可能采用较高的蒸汽参数.     

热管式反应器的应用研究进展

概述了热管式反应器的特点,对热管式反应器在各类工艺过程中的应用研究现状进行了综述。     

滚动轮胎表面对流换热的萘升华模拟研究

根据热质比拟的基本原理 ,采用萘升华技术 ,在风洞中利用直线运动的旋转圆盘模拟研究了滚动轮胎表面的对流换热系数。当风速为 14m·s- 1 时 ,轮胎表面对流换热系数与汽车行驶速度呈线性关系 ,随着汽车行驶速度的增大 ,轮胎表面对流换热系数也增大 ,其经验式为h =5 2 99+1 2 43 8v。     

双酚A苯并恶嗪一环氧树脂基印制电路基板的研究

采用双酚A苯并恶嗪与环氧树脂共混改性制得胶液,经浸渍玻璃布、烘焙、压制得到了一系列玻璃布覆铜板基板其中含溴型基板的玻璃化转变温度为145.2℃,加强耐热性在300s以上,常温下表面电阻率和体积电阻率分别为1.51×1014Ω、5 75×1014Ω@m,无溴型基板玻璃化转变温度为160.3 ℃,加强耐热性在300 s以上.常温下表面电阻率和体积电阻率分别为1.91×1013Ω、5.01×1013Ω@m,覆铜板的耐浸焊性能优异,达到60s以上     

采用不同锰源合成尖晶石LiMn2O4正极材料

The spinel LiMn2O4 cathode material was synthesized with the solid-state reaction method. Four manganese compounds including electrolytic manganese dioxide (EMD), MnCO3, Mn3O4 and nano-EMD were used as Mn sources while LiOH·H2O was used as the uniform Li source. The crystal structure characteristics of these samples produced were investigated by means of XRD, SEM, particle size distribution analysis and specific surface area testing. Their electrochemical properties were also studied by comparing their specific capacity, charge and discharge efficiency and cycle performance.     

Heat capacities of polyethylene and linear fluoropolymers

Heat capacities at constant pressure, C_p, and at constant volume C_v, were calculated with the help of normal mode frequency spectra and compared to experimental data for crystalline or semicrystalline polyethylene, poly(vinyl fluoride), poly(vinylidene fluoride), polytrifluooroethylene and poly(tetrafluoroethylene). A calculation scheme using a Tarasov function for 2N skeletal vibrational modes and an approximation of the residual 7N normal modes from known data on polyethylene and polytetrafluoroethylene is developed for all homologous, linear fluoropolymers. N is the number of carbon backbone atoms of the repeating unit. Calculations can be carried out over the whole temperature range 0 K to melting. For the two theta temperatures and the constant A₀ used for C_v to C_p conversion, fluorine-concentration dependent curves are given. The relations are expected to hold also for copolymers and blends of intermediate fluorine contents. Recommended experimental (data bank) heat capacities agree to ±2.5% with the calculations.     

我国炼焦炉改造与发展的取向

本文从我国煤炭资源特点、节能及技术进步出发，描绘出我国炼焦炉改造与发展的未来轨迹。即焦炉大型化，开发捣固焦炉；铸造焦生产及专业生产铸造焦焦炉；推广多种低热值燃气加热焦炉技术；添加粘结剂炼焦与煤预热炼焦工业化。