煤泥浮选中矿物颗粒间相互作用力的研究进展

煤泥浮选是选煤流程中的一个重要环节,改善煤泥浮选效果是提高煤炭高效洁净利用和企业经济效益的关键,煤泥浮选过程的强化越来越受到选煤行业的重视。论文总结了当前煤泥浮选体系中矿物颗粒间相互作用力的最新研究方法和研究进展,综述了浮选药剂、电解质、矿浆pH值、钙镁离子、机械搅拌、磁化处理、电化学处理、超声波处理以及微生物对矿物颗粒间相互作用力的影响规律及机理,对实现煤泥的高效分选有重要的参考价值。     

改性碳酸氢钠形貌及热分解性能的研究

将环氧树脂(EP)对不同粒径的碳酸氢钠(SB)进行包覆改性得到改性碳酸氢钠(EP@SB),采用扫描电镜(SEM)、红外(FTIR)、差示扫描量热法(DSC)和热重(TG),探究不同粒径SB下改性碳酸氢钠形貌及热分解性能。结果表明,不同粒径的SB在EP包覆改性后其热分解性能有明显改善,其中200目的SB改性后效果较理想,起始分解温度从120.1℃升高到155.2℃,提高幅度达35.1℃;分解温度区间从58.6℃缩小到了22.6℃。极大扩宽了轻量化制品的应用范围。     

A viable approach to prepare 3C-SiC coatings by thermal MOCVD using commercial grade precursors

A series of 3 C-SiC coatings were prepared by organometallic chemical vapor deposition (MOCVD) using precursor solution containing a varying proportion of commercial-grade hexamethyldisiloxane (HMDSO) and n-hexane. The phase composition, bonding state, and microstructure of 3 C-SiC coatings were studied in detail by grazing incidence X-ray diffraction (GIXRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The microstructure and mechanical properties of the optimal 3 C-SiC coating were characterized by scanning transmission electron microscopy (STEM) and nanoindentation, respectively. Our results revealed that the amount of undesired graphite phase can be significantly reduced in the 3 C-SiC coating by introducing hydrogen gas in the reaction chamber alongside increasing the ratio of HMDSO/n-hexane in the precursor mixture. The STEM results revealed that the optimal coating was predominantly composed of nano-crystalline 3 C-SiC grains alongside a small amount of amorphous graphite. The hardness and elastic modulus of the optimal coating were 38.19 GPa and 363.2 GPa, respectively.     

VR-Electricians: Immersive storytelling for attracting students to the electrical construction industry

Although it is projected to have significant employment growth in the electrical construction industry, there are not enough young people to join the workforce. It is indispensable for the future of work in construction to explore emerging technologies and effectively attract the younger generation to the construction industry. This paper explores the innovative use of 360-degree immersive environments powered by virtual electricians to tell success stories of the electrical construction trades on the field (VR-Electricians) and understand how such an immersive storytelling approach can attract young people to join the industry. A pretest-posttest design was used for the VR-Electricians assessment. VR-Electricians was found to significantly enhance several aspects of students’ attitude towards the electrical construction industry. VR-Electricians was also rated as a highly usable and easy-to-use system. The outcomes of this study provide construction researchers and practitioners an understanding of how immersive storytelling can be used as a powerful technology-mediated method for attracting students to their field.     

Microstructure Evolution of Ni-Co Alloys During Crystallization and Amorphization Process

Journal of Superconductivity and Novel Magnetism - A molecular dynamics simulation has been conducted in Ni73Co27 and Ni74Co26 alloys during rapid solidification at the cooling rate of...     

土壤重金属光谱检测方法的应用研究

针对土壤重金属,在简述其危害的基础上,对其光谱检测方法具体应用进行深入分析,以此为实际的重金属检测工作提供理论参考,保证检测结果准确性与可靠性。     

控制点CGCS2000坐标的联测及解求

CGCS2000坐标系是我国目前精度最高的坐标系,其推广使用具有重大意义。文中在安装并学习美国高精度GPS基线处理软件GAMIT软件基础上,以4个无坐标信息观测墩为例,进行观测数据采集与数据处理方案的设计,以期获取4个观测墩的CGCS2000坐标。最终结果表明,各质量指标均满足限差要求,且平差后最弱边中误差满足《工程测量规范》(GB50026-2007)三等工程控制网的要求。     

Effect of ball-milling parameters on the rheological properties of mold powder slurry

In this study, mold powder slurries with high solid loading and low viscosity were prepared during the ball-milling process for improving the homogeneity and mechanical properties of granules after spray-drying. The effect of ball-milling parameters, such as solid loading, binder/dispersant content, and ball-milling time, on the flowability, dispersibility, stability, and rheological behavior of mold powder slurries was systematically investigated by rheology observation and sedimentation tests. As these parameters varied, the slurry exhibited the shear-thinning behavior of a non-Newtonian fluid with a shear rate range of 0–50 s^?1, which was adequately described by the Herschel-Bulkley model. The optimal parameters that optimized the flowability, dispersibility, and stability of the slurry, along with its rheological behavior, were chosen as follows: solid loading, 60 wt%; modified sodium carboxymethyl cellulose binder content, 1.0 wt%; sodium tripolyphosphate dispersant content, 0.5 wt%; ball-milling time, 60 min.