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961.
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分析煤气化装置磨煤系统在运行中遇到的问题,通过持续改进,降低了系统能耗,提高了装置运行效率,减少了有害气体排放,为保障气化炉高负荷长周期稳定运行提供了保障. 相似文献
965.
966.
Fabrication and Characterization of Electrospun Dopants/PS Composite Fibers with Porous and Hollow‐Porous Structures 下载免费PDF全文
Lidong Tian Junwei Gu Xingfeng Lei Zhaoyuan Lv Mingtao Qiao Changjie Yin Qiuyu Zhang 《大分子材料与工程》2016,301(5):625-635
Three different dopants are used to fabricate electrospun dopants/polystyrene (dopants/PS) composite fibers from PS solution and PS sol. The relative humidity and the influence of the dopants on the morphologies, diameter, porous structures, and dopant distribution of electrospun PS fibers are investigated. Compared to those obtained from PS solution, electrospun dopants/PS composite fibers from PS sol with hollow‐porous and multichannel hollow‐porous structures present significant advantages due to the multi‐stage degree of interfacial structure and diversity of the internal environment. In comparison to coaxial electrospun PS fibers, the electrospun dopants/PS composite fibers from PS sol obtained in one step have an improved yield and a simplified technological process simultaneously, leading to significant competitiveness in fields such as catalysis, fluidics gas storage, and sensing.
967.
Fengjun Yin Xiaohui Yang Lei Zheng Ling Fang Sha Wang Hong Liu 《American Institute of Chemical Engineers》2022,68(6):e17669
Acid–base transport is integral to many important interfacial reactions in various fields of chemistry, but its theoretical foundation is lacked. Herein, a common acid–base transport model is established owing to the success in deriving buffer transport equations. This model is applicable to most buffer systems by flexibly integrating the transport equations in terms of buffer components, and is verified through the model relationships of buffer transport limiting current by using hydrogen evolution reaction experiments. Based on model calculations, two diagram approaches are proposed to depict the dynamic pH response and aid buffer operation optimizations. The model and methods allow us to quantify the rate-limiting effect of acid–base transport on interfacial reactions and to precisely control the effect through medium regulations. Furthermore, the model has laid the foundation of dynamic pH effect on species transformation and process mechanism, which can be of wide interest in the chemistry encompassing interfacial reactions. 相似文献
968.
Hua Yang Shi-Xiao Wei Han Chen Lang Chen Chak-Tong Au Ting-Liang Xie Shuang-Feng Yin 《American Institute of Chemical Engineers》2022,68(10):e17810
A high-throughput (105.5 g/h) passive four-stage asymmetric oscillating feedback microreactor using chaotic mixing mechanism was developed to prepare aggregated Barium sulfate (BaSO4) particles of high primary nanoparticle size uniformity. Three-dimensional unsteady simulations showed that chaotic mixing could be induced by three unique secondary flows (i.e., vortex, recirculation, and oscillation), and the fluid oscillation mechanism was examined in detail. Simulations and Villermaux–Dushman experiments indicate that almost complete mixing down to molecular level can be achieved and the prepared BaSO4 nanoparticles were with narrow primary particle size distribution (PSD) having geometric standard deviation, σg, less than 1.43 when the total volumetric flow rate Qtotal was larger than 10 ml/min. By selecting Qtotal and reactant concentrations, average primary particle size can be controlled from 23 to 109 nm as determined by microscopy. An average size of 26 nm with narrow primary PSD (σg = 1.22) could be achieved at Qtotal of 160 ml/min. 相似文献
970.
Jun Wang Jian Zhang Kaijie Ning Dewei Luo Hao Yang Danlei Yin Dingyuan Tang Ling Bing Kong 《Journal of the American Ceramic Society》2016,99(5):1671-1675
Highly transparent 0.5 at.% Tm:Y2O3 ceramics were prepared by using solid‐state reaction combined with vacuum sintering method, with ZrO2 and Al2O3 as sintering aids. Doping amount of ZrO2 was fixed at 1 at.%, while the effect of Al2O3 on densification, microstructure evolution, and transmittance of the Y2O3 ceramics was carefully studied. It was found that the addition of Al2O3 was very effective in improving densification of Y2O3, due to the formation of an Al‐rich eutectic phase Y4Al2O9 (YAM) during the sintering process. As the content of Al2O3 was increased from 0 to 81.8 wt ppm, porosity of the ceramics was decreased and transmittance was increased. However, when the content of Al2O3 was increased to 137 wt ppm, a secondary phase began to segregate at grain junctions. Further increase in the amount of Al2O3 led to an increase in both amount and size of the secondary phase. At the optimized content of Al2O3 with 81.8 wt ppm, the Tm:Y2O3 ceramics sintered at 1860°C for 13 h exhibited an in‐line transmittance of 83.0% at 2000 nm and 76.5% at 600 nm. It is expected that this finding can be readily applied to other transparent ceramics. 相似文献