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101.
Ye Yuan Yurui Pan Menglong Sheng Guangyu Xing Ming Wang Jixiao Wang Zhi Wang 《中国化学工程学报》2022,50(10):168-176
Membrane technology features inspiring excellence from numerous separation technologies for CO2 capture from post-combustion gas. Polyvinylamine (PVAm)-based facilitated transport membranes show significantly high separation performance, which has been proven promising for industrial scale-up. However, commercialized PVAm with low molecular weight and excessive crystallinity is not available to prepare high-performance membranes. Herein, the synthesis process of PVAm was optimized by regulating polymerization and acidic hydrolytic conditions. The membranes based on PVAm with a molecular weight of 154 kDa and crystallinity of 11.37% display high CO2 permeance of 726 GPU and CO2/N2 selectivity of 55 at a feed gas pressure of 0.50 MPa. Furthermore, we established a PVAm synthesis reactor with an annual PVAm solution (1%(mass)) capacity of over 7000 kg and realized the scaled-up manufacture of both PVAm and composite membranes. 相似文献
102.
氯氧镁水泥具有高强度、强黏合力、耐磨、抗冲击、低碱性及低腐蚀性等优点,作为无机胶黏剂和胶凝材料已在包括木材加工在内的众多行业中应用。但氯氧镁水泥的耐水性差,严重影响了其规模化应用与推广。在保证氯氧镁水泥力学性能的条件下,如何提高其耐水性成为氯氧镁水泥的研究热点。本文综述了近年来国内外在提高氯氧镁水泥耐水性方面的研究进展,重点总结了不同外加剂应用于氯氧镁水泥改性的方法及作用机理。并对氯氧镁水泥在人造板等领域的发展前景进行了展望,以期为高性能氯氧镁水泥的开发和应用提供理论与技术指导。 相似文献
103.
Alkyd resins are produced with reaction of oil or fatty oil, polyol and polyacid. Alkyd resins are commonly used in coating and paint industry due to ease of application in changing environmental conditions. Linseed oil based paints executed all requirements of technical properties, drying time, storage properties, simplicity in maintenance, appearance, economy, etc. In this study, linseed oil based alkyd resins having different oil contents were synthesized 相似文献
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以渤海某井口平台为例,对自升式钻井船在井口平台上的避让进行了分析。根据拟定钻井船的参数,以及作业水深、井口平台设计参数等,对钻井船就位、避让进行了放样。并在发生碰撞时,提出了解决碰撞的方案,以最小的设计改动满足了避让钻井船的要求。 相似文献
106.
Utilisation possibility of Enterococcus faecalis isolates from neonate's faeces for production of fermented sausages as starter cultures 下载免费PDF全文
Hoa Van Ba Hyun‐Woo Seo Soo‐Hyun Cho Yoon‐Seok Kim Jin‐Hyoung Kim Beom‐Young Park Hyun‐Wook Kim Jun‐Sang Ham Pil‐Nam Seong 《International Journal of Food Science & Technology》2017,52(7):1660-1669
This study aimed at assessing the utilisation possibility of Enterococcus faecalis as starter cultures for production of fermented sausages. The E. faecalis isolates isolated from faeces samples of 5‐day‐old healthy newborn babies, identified by 16SrDNA sequencing and free from virulence determinants as proven by genomic sequencing, were used for fermented sausages production as starter culture. Six treatments (four inoculated with four different E. faecalis isolates, one with commercial starter culture and one control) were prepared. The inoculation with E. faecalis showed a stronger acidification compared with the control. The treatments with E. faecalis showed significantly higher flavour and acceptability scores in comparison with the control or commercial starter culture. Both of commercial starter culture and E. faecalis were positive with tyramine. Apart from the amine production, the inoculation with E. faecalis generally improved the acidifying activity and flavour of the products, suggesting their application potentials in fermented sausages production as starter cultures. 相似文献
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Porcelain, wall/floor tiles, and roofing tiles are classified as traditional ceramics and are produced from natural raw materials such as clay, quartz, and feldspar. The raw materials are selected by the oxide content which provides the desired properties of the final product. However, impurities such as Fe2O3 and TiO2 may have a significant influence on both physical/mechanical properties and aesthetic appearance. Fe2O3, which is of particular importance, causes black maculation formation in tablewares, in which whiteness is essential. The only way to overcome the black maculation is to corrupt the Fe2O3 crystal structure and to employ Fe2+/3+ cation, making a solid solution with a host crystal (i.e. mullite-3Al2O3·2SiO2). The aim of this study is to identify the solubility limit of Fe2O3 in mullite crystals. With the scope of the study, an illite/kaolinite was utilized by adding an increasing amount of Fe2O3 (e.g. 1–2–4–6–8–10?wt%) into the recipes fired at 1300?°C for 3?h after homogenization. According to the mullite phase content, it is concluded that ~ 5?wt% of Fe2O3 could be dissolved in mullite crystal structure on the basis of the Rietveld refinement of the XRD patterns. 相似文献
110.
Şeyda Karaman Esma Tütem Kevser Sözgen Başkan Reşat Apak 《Journal of the science of food and agriculture》2013,93(4):867-875
BACKGROUND: Apples contain a large concentration of phenolic compounds, dependent on factors such as cultivar, harvest, storage conditions, and processing. This study aims to identify the essential phenolic compounds present in various apple varieties, to measure their total antioxidant capacity (TAC) with the CUPRAC (cupric ion reducing antioxidant capacity) and ABTS (2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonate)) methods, and to correlate their TAC values with HPLC findings. RESULTS: The order of TAC (mmol Trolox g?1 fresh weight) of apple peels determined with the CUPRAC method was: Granny Smith > Amasya > Sky Spur > Ervin Spur > King Luscious ≥ Arap Kizi ≥ Lutz Golden. The theoretically calculated TAC values of HPLC‐quantified compounds, with the aid of the combined HPLC‐CUPRAC method, accounted for 18.4–33.5% of the experimentally observed CUPRAC capacity of peel extracts and 19.5–56.3% of flesh extracts, depending on apple variety. CONCLUSION: In synthetic samples of apple antioxidants, the CUPRAC‐TAC values of constituents, identified and analyzed by HPLC, proved to be additive, enabling measurement of the cooperative action of antioxidants using the proposed methodology. Apple peel showed higher contents of phenolics and therefore higher TAC than apple flesh, confirming the health benefit of the consumption of apples together with peel. © 2012 Society of Chemical Industry 相似文献