Fe3+/TiO2光催化剂降解孔雀绿染料的研究

采用快速溶胶法制备纳米TiO2光催化剂,用Fe^3 对其掺杂改性,并进行了催化剂的X-射线衍射分析(XPd3),傅立叶红外光谱分析(FT-IR),BET比表面积的表征,用于光催化降解水中孔雀绿染料的研究．研究了不同催化剂的光催化活性,确定了光催化剂的用量．结果发现60W紫外光辐射80min,孔雀绿可以彻底降解;可见光下,光催化剂对孔雀绿降解120h,其转化率为98%,COD的去除率为75．3%。可见光下孔雀绿的脱色率和COD的变化不一致,并对其产生的原因和孔雀绿的光催化降解机理作了探讨。孔雀绿的光催化降解符合一级动力学反应规律,反应速率常数随催化剂的用量增加而增大,但增大幅度逐渐减小。     

Fabrication and characterization of Ag–TiO2 multiphase nanocomposite thin films with enhanced photocatalytic activity

Ag–TiO₂ multiphase nanocomposite thin films were prepared on quartz substrates by the liquid phase deposition (LPD) method from a mixed aqueous solution of ammonium hexafluouotitanate, silver nitrate and boric acid under ambient temperature and atmosphere followed by calcination at 500 °C for 1 h. The grain growth of anatase was depressed upon Ag⁺ doping. However, silver ions not only promoted (or catalyzed) the formation of brookite phase but also reduced the phase transformation temperature of anatase to rutile. With increasing AgNO₃ concentration, the transmittance and band gap of the composite thin films decreased; however, the intensity of surface plasmon absorption (SPA) peaks increased and their peak position shifted to a longer wavelength range. When AgNO₃ concentration was higher than 0.03 M, the prepared samples consisted of anatase, brookite, rutile and metal silver nanocrystal particles, and their grain size ranges were 5–30 nm. The photocatalytic activity of the Ag–TiO₂ multiphase nanocrystal composite thin films prepared by this method exceeded that of pure TiO₂ thin films by a factor of more than 6.3 when AgNO₃ concentration was kept in the range of 0.03–0.05. This was attributed to the fact that there were many hetero-junctions, such as anatase/rutile, anatase/brookite, Ag/anatase, Ag/rutile and so on, existed in the Ag–TiO₂ multiphase nanocomposite films.     

硫磺装置停工吹硫烟气排放控制方法探讨

介绍了硫磺装置停工采用的全流程吹硫工艺的流程、技术优势、主要操作方法和应用效果,并指出了实现烟气达标排放的操作要点.全流程吹硫工艺是指将酸性气燃烧炉的酸性气切除,引入天然气和空气,在正常操作流程及条件下进行吹硫,该工艺由当量吹硫和过氧钝化2个阶段组成.与传统吹硫工艺相比,全流程吹硫可以最大程度地回收硫,极大地降低烟气碱...     

沸石对海水拌合超高性能混凝土性能的影响

利用沸石部分或完全(体积分数为0%、50%、100%)取代海水拌合超高性能混凝土(UHPC)中的河砂,对比研究了沸石对海水拌合UHPC宏观和微观性能的影响。结果表明,海水拌合促进UHPC的水化,从而缩短UHPC的凝结时间,提高UHPC的抗压强度和自收缩,而沸石吸收氯离子会抑制氯离子的加速水化作用,使海水拌合UHPC的凝结时间延长,抗压强度降低。此外,沸石的内养护作用可以有效改善海水拌合UHPC的自收缩,且效果比在淡水拌合UHPC中更好,这主要是因为沸石在海水拌合UHPC中释水的时间更早且更长。由于多孔沸石的强度低于河砂,所以UHPC的早期抗压强度随着沸石含量的增多而逐渐降低,养护至28 d后,沸石的内养护作用优化了界面过渡区,从而促使后期硬化浆体进一步密实。     

Ultrafast-laser-treated poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) electrodes with enhanced conductivity and transparency for semitransparent perovskite solar cells

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is an important organic electrode for solution-processed low-cost electronic devices. However, it requires doping and post-solvent treatment to improve its conductivity, and the chemicals used for such treatments may affect the device fabrication process. In this study, we developed a novel route for exploiting ultrafast lasers (femtosecond and picosecond laser) to simultaneously enhance the conductivity and transparency of PEDOT:PSS films and fabricate patterned solution-processed electrodes for electronic devices. The conductivity of the PEDOT:PSS film was improved by three orders of magnitude (from 3.1 to 1024 S·cm^–1), and high transparency of up to 88.5% (average visible transmittance, AVT) was achieved. Raman and depth-profiling X-ray photoelectron spectroscopy revealed that the oxidation level of PEDOT was enhanced, thereby increasing the carrier concentration. The surface PSS content also decreased, which is beneficial to the carrier mobility, resulting in significantly enhanced electrical conductivity. Further, we fabricated semitransparent perovskite solar cells using the as-made PEDOT:PSS as the transparent top electrodes, and a power conversion efficiency of 7.39% was achieved with 22.63% AVT. Thus, the proposed route for synthesizing conductive and transparent electrodes is promising for vacuum and doping-free electronics.     

Cl~-和pH值对硝酸磷肥水溶液热安全性的影响

测试了不同氯离子和pH值下硝酸磷肥水溶液的临界爆炸温度,研究了氯离子和pH值对硝酸磷肥水溶液热安全性的影响。结果表明,在硝酸铵含量一定且氯离子存在时,pH值越大,硝酸磷肥水溶液的临界爆炸温度越高;在硝酸铵含量和pH值一定时,氯离子浓度越大,硝酸磷肥水溶液的临界爆炸温度越低。借鉴本研究结果,可以更好地避免硝酸磷肥在生产过程中火灾和爆炸事故的发生。     

红柱石基浇注料的性能研究

以红柱石、矾土熟料和焦宝石为主要原料,制备了红柱石、红柱石-高铝矾土、红柱石-焦宝石以及高铝矾土4种材质的浇注料,对比了4种浇注料的常温性能、加热线变化率、高温抗折强度、抗蠕变性、抗热震性和热导率。结果表明:红柱石-矾土浇注料和红柱石-焦宝石浇注料与高铝矾土浇注料相比均表现出较优的高温性能,可以作为一种新的中间包永久衬用浇注料。     

高锌粉含量的单组分环氧富锌底漆的研制

以自制的改性环氧树脂为基料,锌粉为防锈颜料,制备出干膜中锌粉含量达96%以上的单组分环氧富锌底漆。同时考察了影响漆膜防腐蚀性能和涂料贮存稳定性的因素。实验表明:锌粉的含量在95%～97%时,漆膜的防腐蚀效果最好,经过1 000 h的耐盐雾试验后,漆膜保持完好;采用0.2%有机膨润土和1%聚酰胺蜡搭配使用,有效地解决了单组分环氧富锌底漆中锌粉沉降结块的问题,根据实验结果得到最佳单组分环氧富锌底漆配方,同国外同类型的产品相比具有更好的性价比。漆膜性能优异,VOC含量较低,环保性能好。     

圆孔射流近场湍流特性DNS与RANS模拟的对比研究

对圆孔射流近场的湍流特性进行直接数值模拟（DNS）研究,同时与应用雷诺时均方程的模拟方法（RANS）进行了对比研究。DNS模拟的Re=5000,计算网格3000万,CPU=60。采用MPI并行求解了可压缩的射流守恒方程,包括连续性方程、动量方程、能量方程和理想气体的状态方程。基于DNS数据库,着重研究和评价了RANS模型在预测自由圆孔射流近场湍流特性时存在的问题,同时提出了适用于射流近场湍流粘性系数的分段表达式,可为工程上准确预测湍流切应力提供参考。