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141.
Yingchun Sun Ru Liu Jianfeng Xu Yuhui Sun Jingya Gong Ling Long 《Polymer Engineering and Science》2023,63(4):1274-1288
A durable and environmentally-friendly superhydrophobic coatings for liquid-food residue reduction were prepared by using stearic acid (SA) modified organic montmorillonite (SA@OMMT) and poly(dimethylsiloxane) (PDMS). Due to the natural hydrophobicity of SAs, SA@OMMT provides low surface energy as well as roughness for the coating. PDMS not only provided low surface energy in the coating but also contributed to the bonding of SA@OMMT as a result of its high adhesive properties. In addition, PDMS has good physical properties after curing, which can effectively improve the physical properties and durability of a superhydrophobic coating by the self-assembly method using a PDMS/n-hexane solution. For 1 wt.% SA@OMMT and 5 wt.% PDMS, the resulting SA@OMMT/PDMS (SOP) coating showed the water contact angle (WCA) and water sliding angle (WSA) of 156.3°and 2°, respectively. The prepared coatings have good physical and chemical stability, and they still have superhydrophobicity after physical abrasion tests and exposure to the corrosion solutions. In the meanwhile, the prepared coating also has flexibility and superhydrophobicity after bending and folding. Finally, the coating surface shows highly effective antifouling ability to liquid and solid pollutants. The coating can be applied against different substrates and has potential application in the field of liquid-food residue reduction. 相似文献
142.
《International Journal of Hydrogen Energy》2023,48(59):22379-22388
This paper proposes an environmentally friendly one-pot synthesis approach for the PtCu and PtNi nanoparticles with the gradient structure on the carbon support. This method offers exceptional advantages over other approaches. Among them there is a surfactant-free synthesis, being low-temperature, simple, fast, and one-pot. The bimetallic electrocatalysts with a reduced platinum content for proton-exchange membrane fuel cells have been obtained. The proposed method is promising in terms of scaling and transition to commercial production. In this study, we first attempted to apply the gradient synthesis strategy to the PtNi/C catalysts in order to make this method versatile. We obtained the high-performance PtNi/C and PtCu/C catalysts, exhibiting the specific ORR activity higher than that of the commercial Pt/C catalyst by 3 and 4.6 times, respectively. 相似文献
143.
Manish Mukhopadhyay 《Materials and Manufacturing Processes》2019,34(10):1151-1159
Conventional metalworking fluids carry an acute threat to the environment as these produce a hazardous ambiance. Furthermore, due to their excessive use and imprudent disposal, the risk of environmental pollution exaggerates. The present article is aimed at finding some alternative potential coolants to be applied in small quantity lubrication (SQL) mode for grinding of difficult-to-machine (DTM) material, titanium alloys, which could effectively replace the conventional metalworking fluids while ensuring minimal waste of the coolant. Three unconventional environmentally safe coolants viz. alkaline soap water, sodium nitrite, and propylene glycol are applied in SQL mode while grinding Ti-6Al-4V. Comparative performance analyses of these cutting fluids have been adjudicated, considering responses of force required for material removal, substrate roughness, grinding ratio, and SEM micrographs of chips and ground surface. The results reveal that the environment-friendly unconventional fluids perform better than the conventional Blasocut fluid and the most satisfactory operations are observed under propylene glycol environment on the basis of the relevant parameters and operating range considered herein. 相似文献
144.
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146.
IBC Advanced Technologies’ Molecular Recognition Technology(MRT) SuperLig products selectively and rapidly bind with target species enabling their selective removal from solutions.The MRT process can produce a high purity separation product of maximum added value at a competitive cost.SuperLig products have high selectivity for many target species which can include metal ions,anions,and neutral molecules.In operation,the SuperLig product is first placed in a packed column.A solution containing a mixture of the target species and other chemical species is then passed through the column.The target species is removed selectively by the SuperLig product,the column is washed to remove residual feed solution,and the target species is recovered by a minimal quantity of eluent.The result is a pure and concentrated species that can be kept for its value or disposed of safely.The process is environmentally and ecologically friendly with no organic solvents being used.This paper provides a review of some examples of applications of MRT to separations of interest to the Chinese metallurgical industry.Included are several applications of MRT,including Pd separations from Pt metal refinery streams and low-grade spent catalyst wastes,Rh recovery from spent auto catalyst and other feeds,Re removal from selected impurity ions,Cd removal from Co electrolyte,Bi removal from Cu electrolyte,In and Ge separations from difficult matrices,and removal of bivalent first transition series and other metal ions from acid mine drainage(Berkeley Pit,Montana).Finally,the potential application of MRT to separations involving the recovery of rare earth metals and Li from low-level waste solutions and end-of-life products is discussed. 相似文献
147.
本文对柔丝、蛹蛋白、天丝、彩棉等绿色纤维混纺纱进行芯吸性能和吸放湿过程测试,并利用Origin软件对测试结果进行对比,分析研究不同纱线的吸湿性及湿传递性能,以期找出影响纱线吸放湿性能的较为普遍性的规律,并为开发湿舒适性好的绿色服装面料提供依据。结果表明:含再生纤维的混纺纱的芯吸性能较强,尤其含有皮芯结构的蛹蛋白再生纤维的纱线芯吸性能最好,含有50%以上的柔丝纤维的纱线吸放湿能力最强,其回潮率和吸放湿速率都较高。天然棉/彩棉混纺纱的芯吸性很差,并且其回潮率及吸放湿速率都较低。 相似文献
148.
An economical route for the scalable production of carbon nanofibers (CNFs) on a sodium chloride support has been developed. CNFs have been synthesized by chemical vapor deposition (CVD) method by using metal formate as catalyst precursors at 680°C. Products were characterized by SEM, TEM, Raman spectroscopy and XRD method. By thermal analysis, the purity of the as grown products and purified products were determined. This method avoids calcination and reduction process which was employed in commercial catalysts such as metal oxide or nitrate. The problems such as detrimental effect, environmental and even cost have been overcome by using sodium chloride as support. The yield of CNFs up to 7800 wt.% relative to the nickel catalyst has been achieved in the growth time of 15 min. The advantage of this synthesis technique is the simplicity and use of easily available low cost precursors. 相似文献
149.
粉末涂料100%固体含量、零VOC,广泛应用于建筑铝型材、家用电器、管道防腐、钢筋防腐、金属家具等领域。在集装箱、汽车、卷材、家具、工程机械、船舶、钢结构这七大国家重点整治VOC排放领域,粉末涂料以其卓越的防腐与耐候特性,可实现真正的绿色涂装,其用量会大幅增长。但是在一些大型构件的现场施工中,粉末涂料涂装短期内难有用武之地。随着粉末涂料涂装技术的不断进步,粉末涂料将会有更多的应用空间。 相似文献
150.
动力手套是一种腕部康复训练装置,同时具有辅助的助力功能。康复训练是手腕进行自主康复的一种重要的辅助治疗手段,传统的康复训练装置大多采用电机驱动的刚性外骨骼结构,在运动时急剧变化的冲击力易造成关节二次伤害,同时较大的质量增加了身体的额外负担。基于气动人工肌肉设计并制作了一款柔性可穿戴动力手套装置,能够实现腕关节屈/伸、内收/外展两自由度运动,集康复训练与腕部助力于一体,轻量化柔顺的外骨骼结构提高了其便携性及舒适性。通过嵌入薄膜压力传感器能够感知手掌与物体之间的抓取力,自动实现腕关节助力功能并有效地保护腕部。对腕部进行穿戴静力分析求解手套装置的性能需求参数,并测试气动肌腱的关键指标及手套的整体性能,测试结果表明所设计的动力手套能够满足腕部康复训练要求并具有辅助的助力功能。 相似文献