抛光废渣回收利用于抛光砖生产的研究

现有的抛光砖生产工艺由于在抛光阶段会产生大量的废渣,很难直接回收利用,从而对周边环境造成极大的破坏。其中抛光废渣中含有氯氧镁水泥等杂质是造成抛光废渣直接回收利用时产生坯体膨胀、针孔、变形等缺陷的最重要原因。针对现有的抛光砖在抛光阶段产生大量的废渣难于直接回收再用的难题,本文提出了分类回收、自然沉降、分开使用的最优处理思路,创新性地丰富了抛光废渣回收领域的技术内涵。     

邢钢降低冶金粉灰CaO平均极差的生产实践

邢钢白灰车间日供烧结工序最大粉灰量约为400t,是烧结工序最主要的粉灰供户。担负着为烧结提供优质熔剂的重任。自产冶金粉灰质量的好坏将直接制约烧结生产,影响烧结矿碱度的稳定和固体燃料的消耗,进而影响高炉的顺行程度,最终影响高炉的生铁成本和质量。针对冶金粉灰CaO极差波动较大,制定了改进措施,并取得了显著的效果。     

农药剂型加工企业干制剂加工环境污染浅析

通过分析农药干制剂中的代表性品种可湿性粉剂、水分散粒剂在加工过程中产生的污染,经采取环保措施处理后,污染物对环境影响进行分析可知,只要农药企业以清洁生产为原则,采取可行的环保措施,农药企业的许多污染是可以控制的,对环境影响较小。     

Ordered structure and thermal property of acid-modified high-amylose rice starch

High-amylose cereal starch has a great benefit on human health. Acid modification is very helpful for application of high-amylose starch in food and non-food industries. In this study, the ordered structure of acid-modified high-amylose rice starch was investigated by GPC, HPAEC, ¹³C CP/MAS NMR and XRD. Acid preferentially degraded the amylose, then A chain and short B chain of amylopectin. Relative double helix content and crystallinity both initially increased sharply and then progressively with acid hydrolysis. The relative crystallinity of starches obtained from ¹³C CP/MAS NMR was higher than that from XRD. The onset gelatinisation temperature decreased, while the peak and conclusion temperatures increased with increasing hydrolysis time. The endothermic value initially increased and then decreased with acid hydrolysis. The swelling power decreased while solubility increased after acid hydrolysis. These results add to our understanding of the effect of acid hydrolysis on the high-amylose rice starch.     

Moisture sorption characteristics and glass transition temperature of apple puree powder

The aim of this study was to characterise the influence of different foam‐mat‐drying methods on the moisture sorption characteristics and glass transition temperatures of apple puree powder. Apple puree was foamed with the addition of 2.5% egg albumin and 0.5% methylcellulose. Convective air‐drying and microwave‐drying techniques were used. Also foamed puree with and without maltodextrin (6% or 15% w/w) was freeze‐dried. Moisture equilibrium data of powders were determined by using a static desiccator method in a water activity range of 0.0–0.903. Modulated differential scanning calorimetry (MDSC) was used to obtain the glass transition temperature. No effect of drying method on sorption properties and glass transition temperatures of apple puree powders was observed. The addition of maltodextrin to the apple puree caused an increase in T_g by 10–30 °C depending on the amount of incorporated additive. Addition of maltodextrin significantly reduced the hygroscopicity of apple puree powders.     

石粉用作混凝土掺合料的初探

本文采用比表面积、扫描电镜、活性指数和减水剂吸附量等方法分析了石粉的基本性质,并试验研究了石粉等量取代水泥和粉煤灰的混凝土性能。结果表明:石粉可以作为混凝土掺合料,但宜与粉煤灰复合使用,其取代粉煤灰的掺量不应超过25%。     

基于回归分析的钢渣月度运输量确定方法

通过对武钢钢渣运输量与钢产量历史数据的相关性分析,将其归纳为一元线性回归分析问题;根据建立回归方程的要求,在48个样本基础上,对回归参数进行分析和求解,确定了相应回归参数;最后,对回归方程进行了显著性检验。结果表明,该方法准确有效,可以用于钢渣运输量的计算。     

生物氧化—氰化炭浸提金工艺的优化改造

对三和金业生物氧化—氰化炭浸提金工艺进行了优化改造。通过优化生物氧化作业参数,使其处理能力提高了42.49 t/d;增设氧化洗涤液二段沉淀回收高品位含金微细氧化渣、采用二段沉淀—压滤工艺回收粉炭、增设摇床重选工艺回收氰渣中的金等,金的总回收率提高了0.46%。企业年增产黄金884.4 kg,取得了显著的经济效益。     

Kinetics of emitted mass—A study with three dry powder inhaler devices

The purpose of this study was to understand the kinetics of emptying of micronised salbutamol sulphate (SS) and lactohale 300 (LH300) under varying air flow rates (30–180 L min⁻¹) from three dry powder inhaler devices, Rotahaler^® (RH), Monodose Inhaler^® (MI) and Handihaler^® (HH). Aerosol concentration vs. time profiles, determined through real-time laser diffraction particle sizing, demonstrated that the majority of the powder from RH was emitted within one second while a more prolonged aerosolisation was observed from MI and HH. Peak aerosol concentrations were achieved more rapidly from RH compared to MI for both SS and LH300. Calculated cumulative emitted mass (CCEM) vs. time profiles were obtained from the aerosol concentration vs. time profiles and the emitted mass and the rate of CCEM (k_CCEM), estimated from a modelling approach, increased with increasing air flow rates. The k_CCEMvs. air flow rate profiles of SS and LH300 were significantly different at high air flow rates. The k_CCEM was highest from RH and lowest from MI. Differences in k_CCEM between the devices were related to capsule aperture size while the differences between the materials were due to the powder bed structure. This approach provided an understanding of the rate at which powder mass emptied from dry powder inhaler devices and was proposed to be a powerful development tool for the future powder inhalers.