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101.
Yuning Lou Yajuan Dong Xiaoyong Wang Feirong Gong Min Zhao Zongming Rong 《Journal of surfactants and detergents》2021,24(1):3-13
Two generations of novel linear-dendritic carboxylate surfactants C18-G1-(COONa)2 and C18-G2-(COONa)4 have been synthesized by the divergent method and their structures are characterized by 1H Nuclear Magnetic Resonance and Infrared analysis. The electrical conductivity measurement is used to measure the Krafft temperatures of C18-G1-(COONa)2 and C18-G2-(COONa)4, which are much smaller than those of the corresponding conventional surfactant sodium stearate. The markedly enhanced solubility of two linear-dendritic surfactants is ascribed to the high hydrophilicity of surfactant headgroups induced by the carboxylate and ester groups. The critical micelle concentration (CMC) values obtained from both the electrical conductivity and surface tension measurements indicate that the micellizations of linear-dendritic surfactants become favorable with the increase in the number of the surfactant headgroup. However, the surface activity parameters including the surface tension at the CMC, maximum surface excess, and minimum surface area reveal that C18-G1-(COONa)2 exhibits greater efficiency in absorbing at the air/water interface compared to C18-G2-(COONa)4, owing to their different steric repulsions of the surfactant headgroups. In addition, C18-G1-(COONa)2 and C18-G2-(COONa)4 have higher emulsifying ability than the conventional surfactants sodium stearate and sodium octadecyl sulfate. 相似文献
102.
针对大型软包锂离子电池热物性参数的测定问题,提出适用于该型电池的热参数表征方法. 基于准稳态导热原理,建立电池的传热理论模型. 开展实验研究电池的比定压热容和导热系数与温度的依变关系,分析热损对测试结果的影响,对测试方法的有效性进行验证. 结果表明,电池比定压热容随着温度的升高而线性增大,导热系数受温度的影响较小. 在900 s内可以测得电池热参数在10~60 °C下的变化状况,实验验证结果显示测算精度高于92.3%,具有测算周期短、准确度高和测试灵活等优势. 相似文献
103.
非线性电导材料的应用是解决高压直流电缆附件内部电场集中问题的一种有效方案。因此,通过掺杂钛酸铜钙(calcium copper titanate,CCTO)纳米填料对三元乙丙橡胶(ethylene-propylene-diene monomer,EPDM)进行改性,在较低的掺杂体积分数(2%CCTO)下,复合介质展现出较好的非线性电导率;当掺杂10%CCTO时,非线性系数可达到5.40。但同时发现,高掺杂含量复合介质的击穿场强劣化严重。基于此,选择具有良好绝缘及导热特性的六方氮化硼(boronnitride,BN)与CCTO共同掺杂至EPDM中,研究发现,共掺杂复合介质的击穿场强有明显改善,φ=10%CCTO/ω=9%BN/EPDM的特征击穿场强为90.1 kV/mm(φ为体积分数,ω为质量分数),相比10%CCTO/EPDM(66.3 kV/mm)提高了35.9%,此时,共掺杂复合介质仍然表现出明显的非线性电导特征。此外,探讨了温度对复合介质非线性电导和击穿特性的影响,并对掺杂复合介质的力学性能进行测试分析,研究发现,2种无机填料的掺杂对EPDM力学性能的改善效果较为显著,随着CCTO掺杂含量增加,复合介质的拉伸强度以及断裂伸长率逐渐增加。 相似文献
104.
A simplified two-dimensional model of two-layer porous burner based on pore level is developed.The heat transfer of solid phase in porous burner is seen as the synergistic effects of conduction through con-necting bridges and surface radiation between the solid particles in the model.A numerical simulation study on the characteristics of flow,combustion and heat transfer in the two-layer porous burner is car-ried out using the pore level model,and the effects of the control parameters such as the inlet velocity and solid thermal conductivity on thermal non-equilibrium are investigated.The results show that the flame structure is highly two-dimensional based on pore level.Obvious thermal non-equilibrium in the burner for the two phases and solid phase are observed,the largest temperature difference between the gas and solid phases is observed in combustion zone,while the temperature difference inside the solid particles is largest near the flame front.The results also reveal that thermal non-equilibrium of por-ous burner is much affected by the inlet velocity and solid thermal conductivity. 相似文献
105.
太阳能发电技术中传热性能的优劣影响着太阳能的利用程度。选用石墨作为强化相变材料传热性能的添加剂与三元混合熔盐(K2CO3-NaCl-Li2CO3)按照石墨质量分数为5%、10%、15%进行混合制备,使用TC3000通用型导热系数测试仪测定16种试样的导热系数。并测试经历300次循环储能、释能实验试样的导热系数循环稳定性。实验结果表明:添加石墨后的混合相变材料导热系数最高可提升至原混合材料的3.38倍,当石墨的质量分数为15%时,混合相变材料的导热系数最大。在经历300次储能、释能实验后,材料的导热系数基本保持稳定,变化浮动不高于15%。石墨作为强化材料的添加剂,可有效提升强化材料的传热性能,具有实际工程的应用价值。 相似文献
106.
G. Antou F. Hlawka A. Cornet G. Montavon C. Coddet F. Machi 《Journal of Thermal Spray Technology》2004,13(3):381-389
Several studies have been undertaken recently to adapt yttria partially stabilized zirconia (YPSZ) thermal barrier coating
(TBC) characteristics during their manufacturing process. Thermal spraying implementing laser irradiation appears to be a
possibility for modifying the coating morphology. This study aims to present the results of in situ (i.e., simultaneous treatment)
and a posteriori (i.e., post-treatment) laser treatments implementing a high-power laser diode. In both cases, the coatings
underwent atmospheric plasma spraying (APS). Laser irradiation was achieved using a 3 kW, average-power laser diode exhibiting
an 848 nm wavelength. Experiments were performed to reach two goals. First, laser post-treatments aimed at building a map
of the laser-processing parameter effects on the coating microstructure to estimate the laser-processing parameters, which
seem to be suited to the change into in situ coating remelting. Second, in situ coating remelting aimed at quantifying the
involved phenomena. In that case, the coating was treated layer by layer as it was manufactured. The input energy effect was
studied by varying the scanning velocity (i.e., between 35 and 60 m/min), and consequently the irradiation time (i.e., between
1.8 and 3.1 ms, respectively). Experiments showed that coating thermal conductivity was lowered by more than 20% and that
coating resistance to isothermal shocks was increased very significantly. 相似文献
107.
AlCl3-BMIC离子液体的电导率 总被引:2,自引:0,他引:2
研究AlCl3-BMIC(氯化-1-甲基-3-丁基咪唑)离子液体电导率与温度、组分之间的关系。结果表明:当离子液体中AlCl3的摩尔分数x(AlCl3)<0.667时,离子液体的电导率随着x(AlCl3)的增加而增大;但在0.6670.5的路易斯酸性区域,x(AlCl3)对温度系数α、β的影响均不明显。 相似文献
108.
109.
110.
1 INTRODUCTIONWorldwide research and efforts are currentlyunderway to fabricate all solid state, rechargeableLi and Li ion batteries utilizing Li+ conductivepolymer electrolytes[1]. Solid polymer electrolytespossesses many advantages including high ionicconductivity, high specific surface energy, solventfree, wide electrochemical stability windows, lightand easy processability[2]. Apart from polyethy lene oxide ( PEO )[3], poly ( vinyl alcohol )(PAV)[4], … 相似文献