Effect of operating conditions in removal of arsenic from water by nanofiltration membrane

The removal of arsenic from synthetic waters and surface water by nanofiltration (NF) membrane was investigated. In synthetic solutions, arsenic rejection experiments included variation of arsenic retentate concentration, transmembrane pressure, crossflow velocity and temperature. Arsenic rejection increased with arsenic retentate concentration. Arsenic was removed 93-99% from synthetic feed waters containing between 100 and 382 μg/L as V, resulting in permeate arsenic concentrations of about 5 μg/L. Under studied conditions, arsenic rejection was independent of transmembrane pressure, crossflow velocity and temperature. In surface water, the mean rejection of As V was 95% while the rejection of sulfate was 97%. The co-occurrence of dissolved inorganics does not significantly influence arsenic rejection. The mean concentration of As in collected permeated was 8 μg/L. The mean rejection of TDS, total hardness and conductivity were 75, 88 and 75% respectively.     

自含砷合碳难处理金矿中提取金的研究─Ⅰ.氨水脱砷-石灰加压氧化-氰化

针对甘肃省坪定金矿含金、砷高、金部分地赋存于脉石、脉石为碱性、属于难选难冶矿的特点，提出了氨水脱砷－石灰加压氧化－氰化新工艺．当原矿含金8．7g／t及13．0％砷时，砷可脱除95％，金可浸出85％．技术及经济指标预计均较满意．     

用于电脑磁头生产的电子级NMP质量监控方法

电子级NMP溶剂在电脑磁头生产中用作脱蜡剂、脱脂剂和污渍清洁剂。介绍了适用于电脑磁头生产的电子级NMP溶剂的质量控制项目(纯度、色度、水分、阴离子含量、硅油、微粒、pH值、重金属、有机痕量杂质、腐蚀试验等)和测试方法。     

Effect of the metal oxide loading on the activity of silica supported MoO3 and V2O5 catalysts in the selective partial oxidation of methane

Precipitated silica catalysts loaded with either MoO₃ (0.2–4.0 wt%) or V₂O₅ (0.2–5.3 wt%) have been studied in the selective partial oxidation of methane to formaldehyde with molecular oxygen at 520 °C. The functionality of the SiO₂ surface towards the formation of HCHO is significantly promoted by V₂O₅, while it is depressed by the MoO₃.     

金昌冶炼厂污酸污水处理装置简介

介绍了污酸污水处理装置的工艺流程、工艺特点和主要设备。来自净化工序的污酸脱出二氧化硫后进行两级石灰石乳中和生成石膏浆；石膏浆经浓密机沉降，底液经hrox压滤机脱水，浓密机上清液和压滤机滤液汇入石膏滤液槽与硫化钠反应生成硫化物沉淀；硫化物沉淀经浓密机沉降，底流经陶瓷过滤机过滤，滤液和浓密机上清液自流到污水处理工序进一步处理。来自污酸处理工序和各车间的污水混合后进行一级石灰乳中和、硫酸亚铁除砷、二级石灰乳中和，实现达标排放。运行3年来，污酸污水处理装置各项指标均达到设计要求。     

试验温度和停放时间对胶料加工性能的影响

研究试验温度和停放时间对胶料加工性能的影响。结果表明，试验温度对胶料的门尼粘度、门尼焦烧时间和硫化特性均有一定影响。门尼粘度测定的试验温度选择100℃；门尼焦烧时间测定的试验温度一般选120℃，SBR胶料可提高至130℃左右，以缩短试验时间；硫化特性测定的试验温度一般选185℃。试验前模腔达到规定温度后再保持15min，以使转子与模腔温度一致。胶料停放时间应控制在2h左右。     

稠油O/W型乳状液稳定性的研究

以大庆黑帝庙稠油为研究对象，依据稠油乳化降粘原理及O／W型乳状液的形成机制，考察了表面活性剂类型及添加量，碱的添加量，温度、油／水比、振荡方式等因素对稠油O／W型乳状液稳定性的影响。为筛选降粘剂复合配方及选择降低粘工艺提供了必要的基础数据。     

掺煤矸石的水泥性能与颗粒群分布的关系研究

将不同细度的煤矸石、纯硅酸盐水泥分别按30％和70％的比例混合，测其胶砂流动度、净浆标准稠度用水量和3d、28d胶砂抗压强度。以宏观性能指标为z轴，水泥与煤矸石的中位径D50之差为x轴，水泥与煤矸石混合样的中位径D50为y轴，进行三维区域图分析。给出各项性能指标发展趋势与水泥、煤矸石的相对位置以及混合体系总体细度的相互关系。     

The effect of water on the tensile yield of polystyrene

When PS is tested in tension but immersed in water the yield stress is unchanged and the crazing stress is increased, as compared with tests conducted in air. The crazing pattern is otherwise unchanged. If the PS is first equilibrated with water and then tested under water, both crazing stress and yield stress are reduced. A very large number of small crazes are generated which result in a 23% increase in the fracture strain.     

耐水性木材用脲醛粘合剂的研究

研究了改进胶合板用脲醛粘合剂的耐水性的方法。针对脲醛粘合剂耐水性低的原因,提出在胶液中添加碱性物质——耐水添加剂,可显著改善胶合板的耐水性,几种添加剂并用,胶合板可达一级耐水板的水平。