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991.
Małgorzata Kowalska Anna Żbikowska Bolesław Kowalski 《Journal of the American Oil Chemists' Society》2014,91(10):1703-1710
The aim of this work was to develop a new fat by enzymatic interesterification of mutton tallow with rapeseed oil. It was assumed that by inducing hydrolysis of fats by addition of water to the enzymatic preparation (8, 10, 15 wt%) natural emulsifiers would be produced in the reaction environment. Fat blends obtained from the enzymatic reactions were evaluated as a fat base for emulsion systems. It was found that the fat resulting from interesterification in the presence of Lipozyme RM IM (immobilized lipase from Rhizomucor miehei, Novozymes Bagsvaerd, Denmark) with 15 wt% of water possessed the highest content of polar fraction (MAG and DAG), and served as the most suitable blend for emulsification, producing emulsions that exhibited the highest stability. 相似文献
992.
A weather resistant super‐hydrophobic coating that can offer good substrate adhesion and yet to be easily processed at large scale can be of practical use in emerging fields of self‐cleaning and anti‐icing paint, combing all these properties together remains challenging task. Here we describe a composite coating composed of a fluorinated epoxy resin emulsion with embedded in situ surface‐modified dual‐scale nano‐silica, which displayed durable super‐hydrophobicity and excellent adhesive strength. The as‐prepared coating possesses water contact angle of 158.6 ± 1°, sliding angle around 3.8 ± 0.2° which remain stable even under acidic/alkaline, heat/cool, and accelerated aging treatment. The results demonstrate that surface roughness had a micron‐ and nanometer scale distribution with increased particle loading beyond 40 wt %. Through quantitative comparison of surface Attenuated Total Reflection (ATR) with bulk FT‐IR transmission spectra, a gradient coating with surface enrichment of hydrophobic groups was determined. The air‐side fluorinated polysiloxane‐rich layer endows coating with weather‐resistance and ultra‐hydrophobicity while bottom epoxy resin layer enhances substrate adhesion. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40955. 相似文献
993.
Knowledge of the wetting characteristic of mineral surfaces is very important in enhancing the efficiency of separation of valuable minerals from gangue using froth flotation or oil agglomeration. In this paper a capillary rise technique was used to characterize the glass beads surface modified with cationic surfactant. The glass microspheres were used as model particles with a spherical shape and smooth surface to eliminate the roughness effect. The value of the contact angle for water was found to be 21.5 for unmodified beads, and 61.8, 89.7, 68.4 for 0.1, 1.0, 10 mg/gsolid of CTAB, and 39.8, 68.6, 87.9 for 0.1, 1.0, 10 mg/gsolid of DDAHCl, respectively. Data revealed that the adsorption of surfactant onto glass beads decreased the value of the electron donor component, γ-, which defines the hydrophobicity of the surface. Also, the property of the surface was investigated by flotation and oil agglomeration experiments. It was observed that particles with low value of contact angle for water and high for 1-bromonaphthalene and low value of γ- were floated with a recovery equal to 91.1 and 83.1% for CTAB and DDAHCl, respectively, and effectively agglomerated. This indicates that the capillary rise method can be successfully used to predict the wetting properties of solid particles in mineral processing. 相似文献
994.
When time‐series data contain a periodic/seasonal component, the usual block bootstrap procedures are not directly applicable. We propose a modification of the block bootstrap – the generalized seasonal block bootstrap (GSBB) – and show its asymptotic consistency without undue restrictions on the relative size of the period and block size. Notably, it is exactly such restrictions that limit the applicability of other proposals of block bootstrap methods for time series with periodicities. The finite‐sample performance of the GSBB is also illustrated by means of a small simulation experiment. 相似文献
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介绍了GLP(Good Laboratory practice)和SOP(Standard Operating Procedures)的发展过程与实际意义,并将SOP作为管理理念引入材料实验室建设与管理。探讨了材料实验室SOP建设的意义、特点、范围和内容。指出SOP建设与实施可以保障实验室安全、高效运行,保证研究工作质量和研究资料可比性、完整性与准确性。 相似文献
999.
选用填料塔对草酸生产过程中产生的氮氧化物进行吸收处理。对填料塔本体进行了设计计算,结合已有的工程设计经验给出了确定填料塔本体尺寸的具体步骤,并讨论了设计应考虑的主要问题。所采用的工艺有效地降低了生产过程中氮氧化物的排放,降低了生产成本,减少了环境污染。 相似文献
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