Development of the method of production of the ultrafine macrohomogeneous composite powder

ABSTRACT

A method of ultrafine macro-homogeneous composite powder – B₄C–ZrO₂ production using a planetary mill was developed. From the macro-homogeneous composite high-density ceramics, B₄C–ZrB₂ was produced by the method of reactive sintering (in situ) at 2000°C under the pressure of 41–42?MPa. The effect of ZrO₂ grain size and of its distribution in the matrix on the consolidation parameters, and the microstructure of the obtained ceramics was studied.     

The control of paracetamol particle size and surface morphology through crystallisation in a spray dryer

The parameters governing the crystallisation of paracetamol using various conventional techniques has been extensively studied, however the factors influencing the drug crystallisation using spray drying is not as well understood. The aim of this work was to investigate the crystallisation of an active pharmaceutical ingredient through evaporative crystallisation using a spray dryer to study the physicochemical properties of the drug and to use semi-empirical equations to gain insight into the morphology and particle size of the dried powder. Paracetamol solutions were spray dried at various inlet temperatures ranging from 60 °C to 120 °C and also from a series of inlet feed solvent compositions ranging from 50/50% v/v ethanol/water to 100% ethanol and solid-state characterisation was done. The size and morphology of the dried materials were altered with a change in spray drying parameters, with an increase in inlet temperature leading to an increase in particle Sauter mean diameter (from 3.0 to 4.4 µm) and a decrease in the particle size with an increase in ethanol concentration in the feed (from 4.6 to 4.4 µm) as a result of changes in particle density and atomised droplet size. The morphology of the dried particles consisted of agglomerates of individual crystallites bound together into larger semi-spherical agglomerates with a higher tendency for particles having crystalline ridges to form at higher ethanol concentrations of the feed.     

档案工作与创新思维

面对新世纪和知识经济新世代的到来，提出如何在档案工作中搞好创新思维。     

DZ型单体液压支柱柱头加工工艺及专用工装设计

介绍了DZ型单体液压支柱关键零件一柱头的加工工艺和专用工装设计,特别介绍了车床改镗床后加工特异工件内孔的特点。通过技术改造,形成柱头加工流水线,确保产品质量,提高生产效率。     

浦东机场跑道冲击碾压地基处理试验研究

针对浦东机场跑道系统的地质条件，提出了“井点降水＋垫层＋冲击碾压”地基处理试验方案，在试验过程中进行了监测和检测，对试验数据进行了分析，为大面积地基处理设计、施工和检测标准的制定提供了直接依据。     

深部开采煤柱载荷在底板岩层传递影响角的探讨

在阐明深部巷道围岩变形机理的基础上，对煤柱支承压力在底板传播规律和煤柱载荷在底板岩层传递影响角进行了分析，并结合实测资料，提出了测定煤柱影响的方法，为深部开采底板巷道合理位置选择提供了依据。     

冻土钻孔内的温度分布——冻土钻探专题之一

分析了冻土钻孔中温度分布的意义 ,提出了孔内温度的数学模型 ,计算了钻头破碎岩石产生的温度增量 ,指出了防止钻孔坍塌的条件     

人的全面发展与社会主义市场经济

分析人的全面发展与社会主义市场经济的关系,以及在社会主义市场经济条件下,如何实现人的发展.     

我国煤系高岭岩资源特征及加工利用现状

简要介绍了我国煤系高岭岩资源的地质特征和主要的加工技术，指出了存在的一些问题，并提出了相应的解决方案。     

江汉盆地洪湖乌林浅埋型地热田综合评价

江汉盆地南东边缘洪湖乌林地段长江一级阶地第四系松散土层下,发现了浅埋的地下热水。采用直流电测深和联合电剖面对出热点进行区域勘测,在圈出电阻率变化异常的基础上,进一步利用手压井揭露,发现地下存在一个热水体,最高水温可达59℃。从52个手压井探测温度自动圈定的24 m深等水温线图看,水温大于30℃的热水区面积可达0.7 km2,并可反映出三个温度中心。水质检验显示,热水体具有医疗保健功效,与周边冷水体有截然不同的水化学场。多种异常的叠加出现,推测乌林地区地下有一个以水热形式存在的能源热田,至少从三个泉眼不断地向上部冷水介质释放热能。