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71.
The wax deposition rate of water-in-crude oil emulsions based on the laboratory flow loop experiment
This paper aims to develop a mathematical model to predict the wax deposition rate of waxy crude emulsions, combining heat and mass transfer mechanisms. According to the flow loop experimental results, the wax deposition rate increases with the decreasing average temperature of oil/wall in a manner of linear regularity, and shows a downtrend with the increase of water cut due to diffusion resistance. An applicable model is developed regarding emulsion properties, radial temperature gradient, shear stress, and wax diffusion coefficient. In model validation, the prediction results are in good agreement with experimental data with the relative errors within 28.87%. 相似文献
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Coacervate behavior of polyelectrolyte complexes has been studied by many papers. Few studies have focused on the coacervate behavior of amphoteric polymer. In this study, amphoteric copolymer of diallyldimethylammonium chloride (DM) and sodium styrenesulfonate (SS) (the copolymer was noted as DMS) was synthesized with the mole content of SS to DM ranged from 0 to 10%. Firstly, DMS was characterized by static light scattering, FTIR, 1H-NMR, TGA and DSC. Then, its phase and coacervate behaviors were studied. Turbidity was utilized as an indicator for the coacervate formation. It was found that when the SS content was more than 4 mol%, DMS coacervate would be formed in deionized water at a certain concentration. Temperature and pH have no effect on the formation of DMS coacervate. Meanwhile, salts has a great influence on the DMS coacervation. Unlike the results of the other polyelectrolyte complexes, Na2SO4, Na2HPO4, NaCOOCH3, sodium citrate and NaI cannot prevent the DMS coacervate formation. However, the addition of NaCl, NaNO3, NaBr and NaSCN can prevent the coacervate formation. The influence cannot be described by Hofmeister-like behavior. Results of surface tension and fluorescence spectrum presented that the driving forces to formation of DMS coacervate are the electrostatic interaction and the intermolecular hydrophobic interaction. 相似文献
73.
采用Mindlin壳元,对SPF/DB工艺进行了模拟。利用罚函数方法,对板材自身接触问题进行分析,给出了接触板材间的接触力,并提出一种接触搜索判断方法,同时给出了算例。 相似文献
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本文对70 nm超薄多晶硅的掺杂工艺、钝化性能及光伏特性进行了研究。确定了70 nm超薄多晶硅的掺杂工艺,研究表明当离子注入剂量为3.2×1015 cm-3,在855 ℃退火20 min时,70 nm超薄多晶硅的钝化性能可以达到与常规120 nm多晶硅相当的水平,且70 nm多晶硅的表面掺杂浓度达到5.6×1020 atoms/cm3,远高于120 nm掺杂多晶硅的表面掺杂浓度(2.5×1020 atoms/cm3)。基于70 nm超薄多晶硅厚度减薄和高表面浓度掺杂的特点,较低的寄生吸收和强场钝化效应使得在大尺寸(6英寸)直拉单晶硅片上加工的N型TOPCon太阳能电池的光电转换效率得到明显提升,主要电性能参数表现为:电流Isc升高20 mA,串联电阻Rs降低,填充因子FF增加0.3%,光电转换效率升高0.13%。 相似文献
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Tandem Radical Cyclization for the Construction of Difluoro‐Containing Oxindoles and Quinoline‐2,4‐diones 下载免费PDF全文
Fangwei Ding Yuanding Fang Yanqiu Jiang Prof. Dr. Kaifeng Lin Prof. Lei Shi 《化学:亚洲杂志》2018,13(6):636-640
Cu‐catalyzed direct difluoromethylation of activated alkenes through a difluoromethyl radical addition/cyclization to afford difluorinated oxindoles and quinoline‐2,4‐diones has been developed. This method provides convenient access to a variety of oxindoles and quinoline‐2,4‐diones under mild conditions via a proposed tandem radical cyclization process, while tolerating various functional groups well. Moreover, a facile method to construct diverse difluorinated quinoline‐2,4‐diones by visible‐light photoredox catalysis under mild conditions was presented. 相似文献
78.
Li Na Gan Kaifeng Lu Deli Zhang Jinlong Wang Lingzhi 《Research on Chemical Intermediates》2018,44(2):1105-1117
Research on Chemical Intermediates - A three-dimensionally macroporous–mesoporous lithium ion sieve (3DM-H4Ti5O12) was transformed from 3DM-Li4Ti5O12 through washing with HCl solution, which... 相似文献
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Abstract In this article, we extend the definition of uniformly starlike functions and uni- formly convex functions on the unit disk to the unit ball in C^n, give the discriminant criterions for them, and get some inequalities for them. 相似文献
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WANG Jingping ZHAO Junwei & NIU Jingyang Institute of Molecule Crystal Engineering School of Chemistry Chemical Engineering Henan University Kaifeng China 《中国科学B辑(英文版)》2005,(4)
Polyoxometalate chemistry is a very important re- search field in modern inorganic chemistry. Poly- oxometalates have attracted extensive interest owingto their unique physical-chemical and unusual topo- logical properties as well as their great potential… 相似文献