Physical Aging of Amorphous Fructose

ABSTRACT: Physical aging of amorphous anhydrous fructose at temperature 5 °C and at 22 °C was studied using differential scanning calorimetry (DSC). The dynamic glass transition temperature, T_g0 for unaged samples was 16 °C and 13.3 °C for heating rate of 10 °C/min and 1 °C/min, respectively. The fictive temperature, T_f0 for unaged samples calculated by Richardson and Savill method was 12 °C, which is close to the dynamic value obtained from the lower DSC heating rate. The fictive temperature T_f of the aged fructose glasses at temperatures both below and above the transition region was fitted well by a non-exponential decay function (Williams-Watts form). Aging above the transition region (22 °C) for 18 d increased both the dynamic glass transition temperature T_g and the fictive temperature T_f. However, aging below the transition region (5 °C) for 1 d increased the dynamic glass transition temperature T_g but decreased the fictive temperature T_f.     

韶钢4号高炉顺行状况的操作技术

对韶钢炼铁厂4号高炉炉况和操作上存在的问题进行了分析,主要原因是原材料质量较差,精料水平低,同时,高炉操作不能完全适应原材料条件.按照上稳下活工艺的原则,采取合理鼓风动能、活跃炉缸工作状态、稳定热制度、合理中部冷却强度、炉顶小高压操作以及使用上部调节手段等一系列措施,使高炉的炉况顺行得到了较大的改善,各项主要技术经济指标取得相应的进步.2001年利用系数达3.024 t/m3·d,焦比达441 kg/t.     

熔融-固相缩聚法中固相聚合对聚乳酸合成的影响

以L 乳酸单体为原料 ,熔融 -固相缩聚法合成了聚乳酸 ,重点研究了固相聚合的工艺条件。结果表明 ,绝对压力 60Pa ,氯化亚锡为催化剂 ,分段控温 ,可使聚乳酸的粘均分子量提高到固相聚合反应前的 5 3倍。通过对固相聚合产物的结晶度和熔点的分析 ,探讨了固相聚合的机理。     

Acoustic emission method for research and control of friction pairs

One of the new physical methods that provides much information about the processes going on in a friction contact zone in real time is acoustic emission (AE). Basic experimental results of AE in friction are presented and analysed. Using AE signals we can get an indication about the state of the friction processes, about the quality of solid and liquid layers on the contacting surfaces in real time, sometimes about intensity of wear, changing of wear and friction regimes and so on. The influence of sliding velocity, load, roughness and some physical and mechanical properties of the body on the parameters of AE are also given. Some attention to the practical implementation of these techniques for control of capability for work of friction pairs in real conditions are given. Modern methods and devices enable condition monitoring of sliding and rolling bearings.     

濮城油田濮67块低渗凝析难动用气藏挖潜技术研究

濮67块具有埋藏深、物性条件差、储量难动用程度低等特点，目前气藏采出程度很低，开发效果差。通过对濮67块天然气储量再认识，落实了该块储量；通过对濮67块各砂组剩余天然气分布规律的研究，明确了剩余气的下步挖潜方向；并开展了配套的剩余天然气挖潜技术研究，通过在生产中应用，取得了较好的增产效果，提高了气藏的采收率。     

Grain Growth Behavior of 5Cr21Mn9Ni4N Steel Micro-Alloyed by Rare Earth

Grain growth behavior of 5Cr21Mn9Ni4NRE steel was experimentally studied at various solid solution treatment temperatures and holding for different times. The experimental results show that the 5Cr21Mn9Ni4NRE steel has the feature of sharp austenite grain coarsening after solid solution treatment at the temperature above 1150 ℃. RE added in the steel has the benefit to restrain grain growth and increase grain growth activation energy.     

池27井机抽排水采气效果分析

介绍了池27井实施机抽排水工艺取得累计排水13 334.4m3的明显效果.分析了五次检泵的原因.提出了对池27井机抽排水的四点认识.     

新疆油田微生物开采稠油技术研究及矿场试验

通过室内筛选复壮,选育出对克拉玛依稠油具有显著降粘作用的微生物菌种.室内降粘实验结果表明,菌种对稠油的降粘率可达70%,同时菌种可以改善稠油的流体性质.原油族组分分析结果表明,菌种能够降解稠油中的非烃和长链饱和烃.首次在克拉玛依油田进行了6口井的微生物吞吐开采稠油矿场试验,累计增油865t.     

注水开发后期提高油砂体采收率方法探讨

注水开发后期，研究油砂体剩余油分布规律，实施油砂体综合治理，完善油砂体注采关系是提高最终采收率的重要途径之一。按照含油面积、采出程度及生产动态特点将油砂体分为3类。根据每类砂体的不同特点，采取相应的治理措施，取得了较好效果，累积增油18．5kt，增加水驱储量1．08Mt。注水开发后期提高油砂体采收率必须以剩余油的分析研究为指导，以井网对剩余可采储量的控制为前提，以油水井措施的联动为手段，从而达到提高最终采收率的目的。     

Exit effect on hydrodynamics of the internal circulating fluidized bed riser

This is the first time an extensive investigation has been carried out regarding the effects of riser exit geometry on pressure drop and solid behaviour inside the Internal Circulating Fluidized Bed (ICFB) riser, using different riser exit geometries at several operating conditions.The Radioactive Particle-Tracking (RPT) technique was used for solid concentration measurements and solid residence time distribution at the exit zone. Experiments were conducted using Geldart B particles, in the gas superficial velocity range of 4 to 10 m/s. Axial solid hold-up, solid residence time distribution in the exit zone, and the reflux ratio factor k_m, (defined earlier by [E.H. Van der Meer, R.B. Thorpe, J.F. Davidson, Flow patterns in the square cross-section riser of a circulating fluidized bed and the effect of riser exit design, Chem. Eng. Sc. 55 (19) (2000) 4079-4099]), were the main criteria used to investigate the impact of gas-solid separator devices implemented at the ICFB riser exit.Solid residence time distribution results and axial solid hold-up profiles provided clear evidence that the separator device at the riser exit strongly influences the hydrodynamic structure of the ICFB riser. The V-shaped riser exit geometry was found to be the optimum of all the configurations studied.