Sputtered Ir–Ru based catalysts for oxygen evolution reaction: Study of iridium effect on stability

Magnetron sputtered low-loading iridium-ruthenium thin films are investigated as catalysts for the Oxygen Evolution Reaction at the anode of the Proton Exchange Membrane Water Electrolyzer. Electrochemical performance of 50 nm thin catalysts (Ir pure, Ir–Ru 1:1, Ir–Ru 1:3, Ru pure) is tested in a Rotating Disk Electrode. Corresponding Tafel slopes are measured before and after the CV-based procedure to compare the activity and stability of prepared compounds. Calculated activities prior to the procedure confirm higher activity of ruthenium-containing catalysts (Ru pure > Ir–Ru 1:3 > Ir–Ru 1:1 > Ir pure). However, after the procedure a higher activity and less degradation of Ir–Ru 1:3 is observed, compared to Ir–Ru 1:1, i.e. the sample with a higher amount of unstable ruthenium performs better. This contradicts the expected behavior of the catalyst. The comprehensive chemical and structural analysis unravels that the stability of Ir–Ru 1:3 sample is connected to RuO₂ chemical state and hcp structure. Obtained results are confirmed by measuring current densities in a single cell.     

基于熵权TOPSIS的工程咨询机构BIM技术应用能力评价

构建工程咨询机构BIM技术应用能力评价的指标体系,提出改进的熵权TOPSIS评价模型,以4个典型的工程咨询单位为例,进行BIM技术运用能力评价。研究表明,BIM行业的整体水平已经有了明显的提升,但是区域间的发展还存在一定差距。     

综放面本煤层预抽瓦斯的治理技术

为了极大限度地提高本煤层预抽效果，以马兰煤矿为研究对象，针对目前马兰煤矿的瓦斯赋存情况和现阶段所采取的抽放措施，从抽放钻孔的孔径、孔深、布置方式、封孔质量和增加煤层透气性等方面进行探索。实践表明，以上方法的运用，能够有效地提高本煤层预抽抽放效果，保证工作面安全生产。     

Modeling for the electromagnetic properties and EMI shielding of Cf/mullite composites in the gigahertz range

The electromagnetic properties and EMI shielding effectiveness of C_f/mullite composites via the spark plasma sintering were intensively investigated in the gigahertz range (8.2–12.4 GHz). Experimental results have revealed excellent electromagnetic properties and a high value of EMI shielding effectiveness (nearly 40 dB) for C_f/mullite composites with 1.65 vol% carbon fillers at thickness of 2 mm. We quantitatively characterize the contributions of microstructural features to overall EMI shielding effectiveness using a micromechanics-based homogenization model. The EMI shielding effectiveness enhances with respect to the C_f volume concentration before the threshold. The increasing trend of EMI shielding effectiveness with respect to AC (alternating current) frequency can be attributed to enhanced conductivity at high gigahertz range. It is demonstrated that filler and frequency dependent interface effects are essential to obtain excellent electromagnetic properties of C_f/mullite composite. The present research can provide guidances for the design of ceramic-based composites applied in high-temperature EMI shielding devices.     

碳脱氧在钢包顶渣改质中的应用

 为了进一步降低夹杂物缺陷并提高产品质量,基于碳脱氧进行了钢包顶渣改质的研究。冷轧产品的生产工艺为铁水预处理→转炉→RH精炼→连铸,为减少钢中夹杂物质量分数,需要进行钢包顶渣改质,同时降低钢包顶渣TFe质量分数。采用粒碳部分替代铝渣球的方法进行基于碳脱氧工艺的钢包顶渣改质,试验结果表明,顶渣改质效果良好,在顶渣TFe质量分数、中间包钢水游离氧明显降低的同时铸坯中Al₂O₃夹杂物得到优化;“30 kg粒渣+铝渣球”工艺降低生产成本5.16元/t(钢)。     

Enhanced photodegradation of Rhodamine B under visible light by N-K2Ti4O9/MIL-101 composite

N-K₂Ti₄O₉/MIL-101 composites were successfully synthesized by a facile hydrothermal method, and were characterized by powder X-ray diffraction, UV–vis diffuse reflectance spectroscopy, the valence band X-ray photoelectron spectroscopy, field emission transmission electron microscopy, photoluminescence emission spectra, N₂ adsorption–desorption and thermogravimetric analysis. Photocatalytic activities of N-K₂Ti₄O₉, MIL-101 and the composites were investigated by the degradation of Rhodamine B (RhB) under visible light irradiation. The results show that the composites exhibit higher photocatalytic activity as compared with the pure materials. The synergistically enhanced photocatalytic activity of the composites is due to big adsorption capacity of MIL-101 and high separation efficiency of photogenerated electron-hole pairs through interfaces between N-K₂Ti₄O₉ and MIL-101.     

水泥窑余热发电系统用耐磨材料的研制与应用

本研究针对水泥窑余热发电系统的工作条件,根据耐磨材料的损毁机理,采用高铝矾土、煅烧氧化铝粉、黏土、硅微粉等为原料,以磷酸二氢铝为结合剂,以铝酸钙水泥为促硬剂,通过添加掩蔽剂和优化配料工艺,制备了水泥窑余热发电系统用耐磨材料,并对不同处理温度对耐磨材料的性能影响进行了分析。结果表明增强骨料与基质的结合能力有利于耐磨性的提高,磷酸及磷酸盐与氧化铝之间会随着温度的升高生成不同的磷酸铝相,都能够起到结合作用,比采用水泥结合更有利于提高材料在不同温度下的强度和耐磨性。使用结果表明,制备的耐磨材料施工性能优良,凝结硬化时间适当,强度高,抗冲刷性能好,在水泥窑余热发电系统中取得了良好的使用效果。     

亮色系建筑涂料色浆的研制及应用

阐述了自制亮色系色浆的必要性。介绍了自制亮色系色浆的颜料筛选,配方调整及其在建筑涂料中应用后对面漆性能的影响。     

全电动注塑机研究进展及在汽配电子行业中的应用

介绍了全电动注塑机的特色，综述了国内外全电动注塑机在精密注塑、智能注塑、高效注塑和绿色注塑方面的研究进展，并对全电动注塑机在汽配电子行业中的应用作了简单介绍。对双电机同步控制技术的逐渐成熟为全电动注塑机实现大型化提供了助力，全电动注塑机高效、精密、智能、节能、环保的优势在汽配电子行业显示了很好的应用前景。