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The actual composition is known to be highly responsible for the physical and chemical properties of a fuel. To understand the foundational physical properties of an aviation kerosene substitute mixture for hypersonic aircraft, n-undecane, butylcyclohexane, and 1-pentanol were used to construct a ternary system. The values of density (ρ) and viscosity (η) for the ternary system and three corresponding binaries were measured at temperatures T= (293.15 to 333.15) K and pressure p= 0.1 MPa. The Redlich–Kister equation was used to fit the excess molar volumes (VmE) and viscosity deviations (Δη) of the binary systems, while those of the ternary system were correlated with four semi-empirical formulas (Cibulka, Singh, Redlich–Kister, and Nagata–Tamura equations). The experimental results show that the VmEvalues of the three binary mixtures have a positive relationship with the mole fraction of nonpolar components, while Δη values have a negative relationship. The non-ideal behavior of mixtures is discussed from the perspective of molecular interactions and structural effects. This work provides data support and guidance for fuel compatibility research.

The densities (ρ) and viscosities (η) of the ternary system exo-tetrahydrodicyclopentadiene + n-decane + 1,2,3,4-tetrahydronaphthalene and the three corresponding binary systems, exo-tetrahydrodicyclopentadiene + n-decane, 1,2,3,4-tetrahydronaphthalene + n-decane, and exo-tetrahydrodicyclopentadiene + 1,2,3,4-tetrahydronaphthalene, were measured at temperatures ranging from 293.15 to 333.15 K and at pressure p= 0.1 MPa. The densities and viscosities were determined using a vibrating-tube densimeter and an automatic microviscometer based on the rolling ball principle, respectively. The values of excess molar volumes (VmE) and the viscosity deviations (Δη) of every mixture were calculated with the measured data. The VmEand Δη values of the three binary systems and the ternary system were fitted to the Redlich–Kister equation and four semi-empirical equations, respectively. The VmEvalues are negative for the binary systems of exo-tetrahydrodicyclopentadiene + n-decane and 1,2,3,4-tetrahydronaphthalene + n-decane with the minimum at about x= 0.5, while the VmEvalue of the binary system exo-tetrahydrodicyclopentadiene + 1,2,3,4-tetrahydronaphthalene is positive with the maximum at x= 0.5. The Δη values of the three binary systems are negative over the entire concentration range. For the ternary system, the VmEvalues are positive when exo-tetrahydrodicyclopentadiene and 1,2,3,4-tetrahydronaphthalene are dominant. Otherwise, the VmEvalues turn out to be negative. The Δη values are negative over the entire concentration range. These phenomena can be explained by physical interactions and structural effects between components.

Two-dimensional layered chalcogenide WS2, similar to graphene, is considered to be very interesting for materials scientists. However, to make it a useful material platform, it is necessary to develop sophisticated synthesis methods to control its morphology. In this paper, we present a simple approach to prepare various morphologies of WS2nanostructures by direct thermal evaporation of WO3and S powders onto Si substrates sputtered with W film without using any nanostructured W-contained precursors and highly toxic sulfide gases. This method can produce bulk quantities of pure hexagonal, horizontally grown WS2nanoplates, vertically grown nanoplates, and nanoplate-formed flowers simply by tuning the distance between the substrate and source powders. The synthesis mechanism and morphology evolution model were proposed. Moreover, when employed as a thin-film anode material, the Li-ion battery with as-prepared, vertically grown WS2nanoplates presented a rechargeable performance between 3 and 0.01 V with a discharge capacity of about 773 mAh/cm3after recycling three times, much better than its already-reported counterparts with randomly distributed WS2nanosheet electrodes, but the battery with horizontally grown WS2nanoplates could not show any charge–discharge cycling property, which could be attributed to the different structures of WS2anodes for Li+ion intercalation or deintercalation.