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121.
Formation and Phase Behavior of Winsor Type III <Emphasis Type="Italic">Jatropha curcas</Emphasis>-Based Microemulsion Systems
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M. S. W. Nordiyana Munawar Khalil Badrul Mohamed Jan Brahim Si Ali Chong Wen Tong 《Journal of surfactants and detergents》2016,19(4):701-712
The formation and phase behavior of Jatropha curcas-based microemulsion systems, which could potentially be used in enhanced oil recovery applications, has been investigated. Winsor type III microemulsions were obtained by adding n-octane to Winsor type I microemulsion systems prepared using various concentrations of alkyl polyglucoside (APG). To optimize the formulation of type III microemulsion systems, five different types of co-surfactants, i.e. normal butyl alcohol (NBA), isobutyl alcohol, isopropyl alcohol, fatty acid alcohol C8 (FAC8) and fatty acid alcohol C8/C10 (FAC8/C10) were used. The microemulsion phase behavior was determined along with particle size distributions by dynamic light scattering measurements. Results show that the optimum Winston type III system can be achieved by mixing 3 wt% of NBA, 1 wt% APG and 3 wt% NaCl. At the optimum formulation, the IFT reached a minimum value (0.016 mN/m) and formed very small emulsion droplets with a narrow particle size distribution. 相似文献
122.
A.M.C. SouzaN.R. Demarquette 《Polymer》2002,43(14):3959-3967
In this paper, the compatibilization of polypropylene (PP)/high-density polyethylene (HDPE) blend was studied through morphological and interfacial tension analysis. Three types of compatibilizers were tested: ethylene-propylene-diene copolymer (EPDM), ethylene-vinylacetate copolymer (EVA) and styrene-ethylene/butylene-styrene triblock copolymer (SEBS). The morphology of the blends was studied by scanning electron microscopy. The interfacial tension between the components of the blends was evaluated using small amplitude oscillatory shear analysis. Emulsion curves relating the average radius of the dispersed phase and the interfacial tension to the compatibilizer concentration added to the blend were obtained. It was shown that EPDM was more efficient as an emulsifier for PP/HDPE blend than EVA or SEBS. The relative role of interfacial tension reduction and coalescence reduction to particle size reduction was also addressed. It was observed that the role of coalescence reduction is small, mainly for PP/HDPE (90/10) blends compatibilized by EPDM, EVA or SEBS. The results indicated that the role of coalescence reduction to particle size reduction is lower for blends for which interfacial tension between its components is low at compatibilizer saturation. 相似文献
123.
端面粘贴包覆火药界面粘结强度研究 总被引:4,自引:3,他引:4
包覆火药装药控制燃气生成速率,降低弹性温度系数,提高弹丸初速的效果部分来自于包覆层的作用,对预制包覆层端粘包覆火药,其包覆层的厚度,密度,强度等性能已根据弹道和装药表确控制,包覆层与基药的界面粘结度就决定了包覆层控制燃气生成速率的有效性和可靠性,它是检验端面粘贴包覆火药工艺质量的关键指标,本文采用落锤实实验检包覆火药的界面结强度,研究了粘结工艺条件对端面粘贴包覆火药界面粘结强度的影响,通过实验选择出了合适的粘结剂及粘结工艺条件,制备了界面粘结强度良好的端面粘贴包覆火药。 相似文献
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126.
河北省某碱性长石花岗岩铷矿,稀有金属以铷为主,伴生有锂、铯、铌、钽。铷和铯以类质同象的形式赋存于钾长石和铁锂云母中,锂主要以铁锂云母形式存在。铌钽主要以独立矿物存在于铌钽铁矿中。采用"弱磁-强磁-浮选云母-长石石英分离"的联合选矿工艺流程,最终可获得Nb_2O_5品位3 241g/t、Ta_2O_5品位1 091g/t、Nb_2O_5回收率54.32%、Ta_2O_5回收率45.45%的铌钽铁精矿。Rb_2O品位11 941g/t、Li_2O品位25 220g/t、Cs_2O品位2 265g/t、Rb_2O回收率28.51%、Li_2O回收率75.89%、Cs_2O回收率54.77%的云母精矿。Rb_2O品位2 276g/t、Rb_2O回收率54.58%的长石精矿以及SiO_2品位98%以上的石英精矿。回收铷等稀有金属矿的同时,云母、长石、石英亦得到了分选回收与综合利用。 相似文献
127.
湖南某铜钨矿建厂时制定的是常年不变的浮钨药剂制度,而矿浆温度的变化会显著影响钨浮选指标,因而选矿厂每年深秋至次年初春钨浮选指标都不理想。为了稳定选矿厂的钨回收效果,减少钨资源的浪费,提升企业的经营业绩,以该选矿厂的铜硫混浮尾矿为试样,进行了选钨药剂制度优化研究。结果表明:新型组合捕收剂ZL-B+LDZ适合该试样中白钨矿的低温浮选,在矿浆温度为10 ℃时,ZL-B与LDZ的质量配合比以3∶2为佳,随着矿浆温度的升高,可通过逐步减少LDZ的用量、增加ZL-B的用量来适应矿浆温度的变化,以获得稳定的、理想的钨精矿指标;在ZL-B+LDZ与现场捕收剂ZL-B用量相当、矿浆温度为10 ℃的情况下,不仅精矿钨品位提高了0.97个百分点,而且钨回收率大幅度提高了25.67个百分点。 相似文献
128.
Preparation and Performance Evaluation of Fatty Amine Polyoxyethylene Ether Diethyl Disulfonate for Enhanced Oil Recovery in High‐Temperature and High‐Salinity Reservoirs
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Yan Zhang Qing You Jichao Fang Yifei Liu Mingwei Gao Hongfu Fan Caili Dai 《Journal of surfactants and detergents》2018,21(4):489-496
To enhance oil recovery in high‐temperature and high‐salinity reservoirs, a novel fatty amine polyoxyethylene ether diethyl disulfonate (FPDD) surfactant with excellent interfacial properties was synthesized. The interfacial tension (IFT) and contact angle at high temperature and high salinity were systematically investigated using an interface tension meter and a contact angle meter. According to the experimental results, the IFT between crude oil and high‐salinity brine water could reach an ultra‐low value of 10?3 mN m?1 without the aid of extra alkali at 90°C after aging. The FPDD surfactant has strong wettability alternation ability that shifts wettability from oil‐wet to water‐wet. The FPDD surfactant with a high concentration also has good emulsion ability under high‐temperature and high‐salinity conditions. Through this research work, we expect to fill the lack of surfactants for high‐temperature and high‐salinity reservoirs and broaden its great potential application area in enhanced oil recovery. 相似文献
129.
驱油用聚丙烯酰胺溶液界面特性研究 总被引:4,自引:0,他引:4
使用 TRACKR全自动液滴界面张力仪测量了不同试验条件下十二烷 /聚丙烯酰胺溶液界面扩大、缩小时的流变特征及界面张力 ,开发出了用以表征液膜强度的界面黏弹性 E的测量方法。在十二烷 /聚丙烯酰胺界面形成稳定的过程中界面 (扩张 )黏弹模量不断增加 ,并逐渐达到恒定 ,其中弹性成分所占比例远大于黏性成分即 E′>E″。考察的聚合物浓度范围为 5 0~ 2 0 0 0 mg/ L ,界面黏弹模量从 1 7.6提高到 3 0 .6m N·m-1。放置 3 d后的聚合物溶液界面黏弹模量保留率为 82 .8%。实验结果表明聚合物浓度变化对界面张力影响不显著。 相似文献
130.
《Journal of the European Ceramic Society》2014,34(8):1989-1996
In this paper, Al2O3 was added to CaO–SrO–B2O3–SiO2 sealing system to tailor the structure of sealing glass–ceramics and glass–ceramics/metal interfacial reaction. The addition of alumina in glasses contributes to increasing fraction of bridging oxygen in silica tetrahedral as well as the change in boron environment from three-fold to four-fold (BO4 → BO3). The devitrification tendency of glasses also decreases with increasing Al2O3 content. The condensed glass structure and increasing residual glass content play opposite roles on the interfacial reaction, consequently resulting in a maximum fraction of Cr6+ in reaction couples between Cr2O3 and glass containing 6 mole% Al2O3 at 700 °C. In addition, the good bonding can be observed at the interface between Cr-containing interconnect (Crofer 22APU) and glass containing 4 mole% Al2O3, held at 700 °C for 100 h. The reported results support the suitability of the prepared glass–ceramics as sealing materials for SOFC applications. 相似文献