Precipitation of calcium and magnesium from seawater using CO2——Effect of temperature and salinity

对CO2法脱除海水中钙离子和镁离子进行研究,控制海水的pH值恒为8,考察温度、盐度对脱钙率和脱镁率的影响。结果表明,盐度35‰的海水,30～50 ℃时脱钙率由90%增长至95%,与此同时脱镁率由0增长至42%;脱钙率、脱镁率随温度升高而升高。在温度为30 ℃时,盐度35‰～105‰的海水脱钙率可由90%增长到97%,与此同时脱镁率由0增长到67%;脱钙率、脱镁率随盐度升高而升高。将得到的固体进行XRD检测可知,产物固相组成随温度、盐度的变化而变化。由此可知,海水盐度为35‰、pH值为8、温度为30 ℃是CO2法高效脱钙的最佳工艺条件。     

Efficient photothermal conversion of Fe2O3–RGO guided from ultrafast quenching effect of photoexcited state

In solar thermal utilization, effective photo capture and photothermal conversion are crucial. Improving the nonradiative transition rate of photoexcited electrons is important to enhance the photothermal conversion efficiency and develop efficient solar thermal utilization. Herein, we designed a new kind of light absorption-enhanced and efficient photothermal conversion material, namely, Fe₂O₃-functionalized reduced graphene oxide (Fe₂O₃–RGO). On the basis of the selective absorption (350–560 nm) of Fe₂O₃ and the synergistic effect of RGO on the quenching energy transfer of the excited state of Fe₂O₃ and ultrafast nonradiative thermal decay of RGO, the optical absorption capacity, and photothermal conversion efficiency of the composites were effectively improved. Fe₂O₃–RGO can be successfully applied to photothermal conversion phase change materials and seawater solar desalination, showing excellent photothermal conversion ability and application prospect.     

无水硫酸镁催化剂在2,5-二氯硝基苯生产中的应用

介绍了以对二氯苯和浓硝酸为原料、无水硫酸镁为催化剂制取2,5-二氯硝基苯的工艺过程;分析了催化剂用量和催化剂循环利用对产物选择性的影响,确定了适宜的催化剂用量和催化剂酸化条件。     

反渗透系统浓水回收利用方案介绍

简要介绍反渗透技术在涂装行业的应用及国内外目前使用较多的几种反渗透系统浓水处置方法,说明当前反渗透系统浓水回收利用情况,分析并提出浓水回收利用方案。     

海水介质下铁基液相催化氧化法脱除硫化氢的实验研究

以天然碱性海水为反应介质,采用Fe基液相催化氧化法,针对质量浓度为10g/m3左右H2S的气体进行了模拟海上钻井平台脱除H2S的实验研究。主要考察了配方溶液、空气过剩因子(ε)、温度、溶液初始pH等工艺参数对脱硫效果的影响,并对反应产生的固体物含水硫磺进行了X射线衍射(XRD)、电子扫描电镜(SEM)表征。通过分析实验结果确定了最佳催化氧化脱除H2S的条件。并发现了产生的固体物质大颗粒硫磺,易于固液分离。     

船用闪蒸-蒸发海水淡化系统的建模与热力分析

针对舰船发动机排放的烟气具有温度高、热容大的特点,结合闪蒸法和蒸发法海水淡化方法,设计了利用发动机烟气余热的闪蒸-蒸发海水淡化系统。建立了各主要设备的热力计算模型,根据设备之间的连接组合关系以及物流传递关系,建立了海水淡化系统的稳态数学模型,利用序贯模块法顺序求解,可实现系统的稳态模拟。模型中考虑了海水温度变化对系统性能的影响,提高了仿真精度。通过实例研究,获得了海水淡化系统的淡水产量与海水流量、系统压力的关系,研究结果表明该海水淡化系统具有较好的运行性能,可满足中小型船舶对淡水的需求,具有良好的节能效果和经济效益。     

海水循环冷却系统铜合金缓蚀剂研究

应用腐蚀失重、弱极化和动态极化曲线等方法,重点研究了黄铜H68A在不同浓缩倍数海水中的腐蚀行为及其缓蚀剂。腐蚀研究结果表明,黄铜H68A的腐蚀速率随时间的延长逐渐降低,温度升高腐蚀速率在50℃达到最大,随浓缩倍数的增大腐蚀速率降低,原海水中腐蚀最重;缓蚀剂研究表明,有机缓蚀剂和无机缓蚀剂复合使用,协同效应明显。采用高复合预膜缓蚀剂含量处理,再在相对低复合缓蚀剂含量正常运行,浓缩倍数N≤2.0时,黄铜H68A、HSn70和HSn62的腐蚀率≤0.01 mm/a,腐蚀得到有效控制。     

一种高效浓缩洗衣液的研制

初步研究了脂肪醇聚氧乙烯醚硫酸钠(AES)、醇醚羧酸盐(AEC_9)、改性油脂、烷基糖苷(APG)及异构醇聚氧乙烯醚等5种表面活性剂在浓缩洗衣液中的应用,通过对去污力、泡沫性能、水溶分散性和酶活稳定性等的测试,将此几种表面活性剂与其他助剂复配,得到一种低泡、高效浓缩洗衣液。测试结果表明,自制浓缩洗衣液稳定,去污力强、可达到4倍浓缩的效果,水溶分散性好,无凝胶出现,酶活稳定性达87.1%。     

Experimental study on the effect of lateral concentrated smoke extraction on smoke stratification in the longitudinal ventilated tunnel

Smoke is the main cause of death in tunnel fires. It is one of the important measures to maintain smoke stratification in the early stage of tunnel fire. This article focused on experimentally studying the combined effect of lateral concentrated smoke extraction and longitudinal ventilation on the smoke stratification, which never be revealed before. The velocity of the smoke layer and air layer, vertical temperature distribution, and the flow patterns of the smoke were measured. It was found that the longitudinal ventilation and lateral concentrated smoke extraction would affect the flow of the smoke and change the shear velocity between the smoke layer and air layer, then, the patterns of the smoke layer will be affected. And the flow patterns with Froude (Fr) number can be classified into three categories: (a)Fr < 0.6 , with stable smoke stratification; (b) 0.6 < Fr < 0.85 , with a stable smoke stratification but the blurring interface; and (c) Fr > 0.85 , the smoke layer is completely unstable. The result can provide a reference for ventilation design of immersed tube tunnels.     

集中载荷作用下组合砌体非线性有限元分析

本文针对图1所示砼柱、砖砌体组合结构计算模型,采用非线性有限元分析方法得出应力及裂缝分布情况。本文分析结果对进一步合理计算此类组合结构极限抗压强度有一定参考价值。