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101.
于秀芳 《曲阜师范大学学报》1998,(3)
研究了二(2_乙基己基)磷酸钠盐—醇—有机溶剂—水体系微乳液的性质,得到了其结构参数,并讨论了其影响因素. 相似文献
102.
Jingyun Ma Hua Tan Hong Liu Yimin Chao 《Particle & Particle Systems Characterization》2021,38(3):2000288
Si-based materials possess huge potential as an excellent anode material for Li-ion batteries. However, how to realize scalable synthesis of Si-based anode with a long cycling life and high-performance is still a critical challenge. Here a water-in-oil microemulsion process followed by UV illumination, calcination, and hydrothermal method to produce yolk-shell Si@void@C embedded in interconnected 3D porous carbon network architecture using silicon nanoparticles is reported. As a result, the sample Si@void@C/C-2 electrode has achieved a reversible capacity of 1160 mA h g−1 at 0.2 A g−1 after 300 cycles and a stable long cycling life of 480 mA h g−1 at 1 A g−1 after 1000 cycles. A full battery with the synthesized anode shows a capacity of 128 mA h g−1 at 0.2 A g−1 as well as good cycling stability after 1100th cycles. Such excellent electrochemical performance is ascribed to its unique structure, the yolk-shell void space, highly robust carbon shells and interconnected porous carbon nets that can improve the conductivity of the electrode, buffer the volume expansion, and also suppress Si nanoparticles stress variation. This water-in oil system makes it possible for mass production of environmentally friendly synthesis of core–shell structure. 相似文献
103.
以CuSO4和NH3·H2O为原料,采用微乳-均匀沉淀耦合法制备了一维CuO纳米棒。用XRD、SEM、TEM、HRTEM和FTIR对产物的结构和形貌进行了表征。结果表明:产物为单斜晶相结构的CuO纳米棒,内部具有孔洞结构,其直径为40~110nm,长度为800~3000nm。可通过改变水核比(ω)、反应物的浓度、反应时间、反应温度等条件实现对CuO纳米棒形貌和尺寸的调控。探讨了可能的反应机理,并用热分析方法考察了CuO纳米棒对高氯酸铵(AP)分解的催化作用。 相似文献
104.
Masashi Haruki Kazuhiko MatsuuraYuichi Kaida Shin-ichi KiharaShigeki Takishima 《Fluid Phase Equilibria》2010
The microscopic phase behavior of the supercritical carbon dioxide (scCO2) + polyethylene oxide-2,6,8-trimethyl-4-nonyl ether (TMN) + water systems at about 3 wt% of TMN were investigated using a synthetic method with a microscope. The two types of TMN (TMN-3 and TMN-10) used in this work had molecular weight distributions caused by the distribution of the number of ethylene oxide groups. Two different types of phase transition were observed when pressure was decreased gradually at a constant temperature from the high pressure at which the transparent phase was observed to the low pressure at which the separate vapor–liquid phases were observed for the scCO2 + TMN-3 + water system at 3 wt% of TMN-3. The transparent phase was colorless under all experimental conditions and the phase transition from a transparent phase to a turbidity phase with small, dispersed droplets was observed at the higher side phase transition (higher phase transition pressure). As the pressure continued to decrease, another phase transition was observed from the phase with small droplets to a state with an accelerating aggregation of droplets (lower phase transition pressure). In the turbidity phase between the higher and the lower phase transition, the degree of turbidity became higher with decreasing pressure. On the other hand, in the phase observed below the lower phase transition, a new liquid phase adhered to the sapphire windows and the wall inside the optical cell. 相似文献
105.
Joakim Balogh 《Advances in colloid and interface science》2010,159(1):22-31
Microemulsions based on nonionic surfactants of the ethylene oxide alkyl ether type CmEn, have been studied thoroughly for around 30 years. Thanks to the considerable amount of published data available on these systems, it is possible to observe trends to make predictions of phase diagrams not yet determined. Strey and Kahlweit, and subsequently Sottmann and Strey, with coworkers have studied and published phase diagrams for systems with a fixed ratio of oil to water, varying the surfactant, the so-called Kahlweit fish-cut diagrams. Some properties of the phase diagrams can be scaled to become general and not system dependent. Here are shown two examples of scaling data from phase diagrams and the use of trends to determine phase diagrams, both inside and outside a dataset. The trends of microemulsions with fixed ratio of surfactant to oil, the so-called Lund-cut diagrams, are also investigated. The trends are used to determine a new phase diagram and this is compared with previously unpublished experimental data on C12E5-Octadecane-Water system. The scalings and trends make it possible to get good estimations of many of the important properties of the phase diagrams, both temperatures and surfactant concentrations of interest, by investigating one sample in the 3-phase region of the balanced fish-cut diagram. 相似文献
106.
研究了电解质和pH值对毒死蜱微乳剂透明温度范围的影响,表面活性剂采用特殊苯乙基酚甲醛树脂聚氧乙烯醚和十二烷基苯磺酸钙(DBSCa)(质量比为3:7)复合物,质量分数75%毒死蜱二甲苯溶液为油相。研究结果表明,电解质的加入对表面活性剂作用的微乳剂透明温度范围均有显著影响,使上限温度明显下降;随阳离子电解质质量分数增加,上限温度下降;随阴离子电解质价数增加,上限温度先略增加后下降。电解质及其价数对下限温度影响均不大。弱酸性介质有利于扩大体系的透明温度范围,使上限温度达到最大值;而强酸性和强碱性介质,均使体系的上限温度下降。体系下限温度随pH值的增加缓慢升高。 相似文献
107.
Aluminium doped ZnO (AZO) nanorods were synthesized by microemulsion method with different types of surfactants. Scanning electron microscopy observations show that the ZnO nanorods have diameters around about 80 nm and lengths up to several micrometers. The room temperature photoluminescence (PL) spectrum of AZO nanorods exhibited a sharp and strong ultraviolet bandgap at 383 nm and a relatively weaker emission associated with the defect level. AZO nanorods synthesized with sodium benzene sulfonate (SBS) surfactant showed lower resistivity than aluminum doped ZnO nanorods synthesized with dodecyl benzene sulfonic acid sodium salt (DBS) surfactant. Resistivity of AZO nanorods synthesized with SBS surfactant showed 2.8×103 Ωcm. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
108.
109.
110.
微乳液—洋茉莉基荧光酮体系吸光光度法测定铬 总被引:2,自引:0,他引:2
该文研究了以微乳液为介质时 ,铬与洋茉莉基荧光酮的显色反应 ,选择 52 5nm为参比波长 ,595nm为测量波长 ,ε为 9.5× 10 4 L·mol- 1·cm- 1,铬量在 0~ 7/2 5μg/mL范围内符合比耳定律 ,方法用于合金钢中铬的测定 ,结果满意 . 相似文献