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81.
A molecular thermodynamic model for polyelectrolyte systems—called pePC-SAFT—is proposed. The effect of charged monomers within the polyelectrolyte chain is explicitly taken into account in the reference term by replacing the hard-chain contribution of the PC-SAFT model by a charged-hard-chain contribution. Moreover, counterion condensation is accounted for to determine the effective number of charges along the polyion as well as of free counterions. The electrostatic contribution of the free counterions is described by a Debye–Hückel term. 相似文献
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83.
Cu‐doped Ni‐based metal–organic frameworks (MOFs) nanomaterials fabricated through a one‐pot hydrothermal reaction were characterized, and their performance as supercapacitor electrode materials was further studied for the first time. The results indicated that the doping of foreign metals and the introduction of K3[Fe(CN)6] in the KOH electrolyte significantly improve the performance of the supercapacitor. The results indicated that the Ni2.6Cu0.4 MOFs material shows the highest specific capacitance (1282 F g?1 at 1 A g?1 in mixed 2 M KOH and 0.1 M K3[Fe(CN)6]) and optimal capacitance retention (85.7% after 2000 cycles). This work provides a feasible optimization strategy for the construction of MOFs‐based supercapacitor electrode materials with excellent performance, and also provides a reliable experimental and theoretical basis for practical industrial production. 相似文献
84.
Boris S. Krumgalz Rita Pogorelsky Kenneth S. Pitzer 《Journal of solution chemistry》1995,24(10):1025-1038
The ion interaction approach developed by Pitzer was used for the prediction of volumetric properties of mixed electrolyte solutions at 25°C based on parameters calculated from experimental data for single-solute electrolyte solutions. Such an approach was shown to be especially effective for application to the calculation of volumetric properties of natural hypersaline brines and of industrial electrolyte solutions of large complexity. The use of the latest recommended sets of volumetric ion interaction parameters for single electrolyte solutions and symmetrical mixing parameters for Na–K–Cl ion combinations considerably improved the precision of the density calculations of highly concentrated mixed electrolyte solutions and of various natural waters. 相似文献
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86.
Vapor pressure,speciation, and chemical activities in highly concentrated sodium borate solutions at 277 and 317°C 总被引:2,自引:0,他引:2
Oleh Weres 《Journal of solution chemistry》1995,24(5):409-438
The system H2O-B2O3-Na2O has been studied experimentally at 277 and 317°C. The activities of water and boric acid have been determined at mole ratios Na/B from 0 to 1.5, and total dissolved solids 3 to 80 weight percent. The activity of boric acid has been fitted to within experimental error using a speciation model with eight complex species. This model is consistent with the model previously published by Mesmer et al. The electrolyte properties of the liquid are modeled using the Pitzer-Simonson model of very concentrated electrolyte solutions. The calculated values of water activity agree with experiment, and the activity of NaOH and pOH have also been calculated. The potassium borate system also was briefly studied at 317°C, and is adequately described by a model with five complex species. The potassium borate liquid is more alkaline at K/B= 1 than a sodium borate liquid at the same mole ratio, but pOH in the two systems is the same at lower mole ratios. 相似文献
87.
微孔型固体偏氟乙烯-六氟丙烯共聚物电解质 总被引:4,自引:0,他引:4
将固体聚合物电解质 (Solidpolymerelectrolyte)用于锂离子电池的研究已经有 3 0年的历史[1] ,从物理角度来看 ,研究过干态型 (DrySPE)、凝胶型 (GelledSPE)和微孔型固体聚合物电解质 (PorousSPE)三大类型[2 ] ;从化学角度来看 ,研究过含氧、含氮、和含氟的等聚合物[1~ 6 ] .微孔型固体含氟聚合物电解质是近 1 0年来才开始研究并受到产业界很大关注的一种SPE .固体聚合物电解质的应用可以解决液体电解质锂离子电池的漏液问题 ,并提高其安全性 ,还可以通过使用塑料包装来减小电池的重量… 相似文献
88.
La0.8Sr0.2Ga0.8Mg0.2O2.8的电化学性质及其在SOFC中的应用 总被引:3,自引:0,他引:3
采用凝胶浇注法制备具有较高氧离子电导率的固体电解质La0.8Sr0.2Ga0.8Mg0.2O2.8粉料.X射线衍射结果表明,于1400℃焙烧后即形成了钙钛矿结构,无杂相存在.探讨了粉料压制坯体的致密化和导电性能在1450℃下与烧结时间的关系,发现烧结时间为18h时其相对密度达98.3%,而在24h的情况下,样品具有最佳的氧离子导电性.采用Ni-Ce0.8Gd0.2O1.9作为阳极,La0.8Sr0.2Ga0.6Ni0.4O2.7作为阴极,组装了平板型固体氧化物燃料电池(SOFC).阳极和阴极分别通入含3%H2O的氢气和空气,750℃时的开路电压为1.04V,最大输出功率密度(P)达252mW/cm2(U=0.48V,J=525mA/cm2). 相似文献
89.
90.