Rotational viscosity of a liquid crystal mixture: a fully atomistic molecular dynamics study

Fully atomistic molecular dynamics （MD） simulations at 293, 303 and 313 K have been performed for the four- component liquid crystal mixture, E7, using the software package Material Studio. Order parameters and orientational time correlation functions （TCFs） were calculated from MD trajectories. The rotational viscosity coefficients （RVCs） of the mixture were calculated using the Nemtsov-Zakharov and Fialkowski methods based on statistical-mechanical approaches. Temperature dependences of RVC and density were discussed in detail. Reasonable agreement between the simulated and experimental values was found.

The Effect of Bio-Oil on High-Temperature Performance of Bio-Oil Recycled Asphalt Binders

Bio-oil recycled asphalt binders in road engineering can help solve the problem of oil shortage and reduce the environmental pollution and sustainability.This paper investigated the road performance of the aged asphalt binder by adding bio-oil so that the aged asphalt binder could be reused to reach purpose of reuse.The residual soybean oil was selected as rejuvenator and blended with aged asphalt binder at 0%,2%,4%,and 6%,respectively.The results showed that bio-oil increased the penetration of aged asphalt binder,the penetration of bio-oil recycled asphalt binder with a bio-oil content of 6%reached the standard of 70#matrix asphalt binder.The addition of bio-oil reduced the viscosity,mixing and compaction temperature of aged asphalt binder.As a common knowledge,bio-oil helps to increase the lightweight components of the aged asphalt binder,which diminishes the high-temperature rutting resistance of bio-oil recycled asphalt binders.The high-temperature deformation resistance of bio-oil recycled asphalt binders had not decreased linearly with the bio-oil dosage.Meanwhile,the hightemperature performance of the bio-oil recycled asphalt binder with a 6%bio-oil was superior to matrix asphalt binder.Bio-oil increased the light components of the aged asphalt binder,thus reducing the high-temperature rheological properties of bio-oil recycled asphalt binders as the bio-oil dosage increases.The above test results showed that the bio-oil could restore the aged asphalt binder to the initial level to reach the reuse target.

Investigating the Calculation of Rotational Viscosity of the Mixture Comprising Different Kinds of Liquid Crystals： Molecular Dynamics Computer Simulation Approach

Molecular dynamics （MD） computer simulation techniques, as a powerful tool commonly utilized by the liquid crystal display （LCD） community, usually are employed for computing the equilibrium and transport properties of a classical many body system, since they are very similar to real experiments in many respects. In this paper we pre- sent molecular dynamics computer simulation results taken for a mixture of the two different kinds of nematic liq- uid crystals （LCs）. We calculated rotational viscosity from Brownian behavior with friction of the mean director of the mixture comprising pentylcyanobiphenol （5CB） and decylcyanobiphenol （10CB） by using molecular dynamics computer simulation, where intermolecular potential parameter is Generalized AMBER force field （GAFF）. Our computed results show a good agreement with the experimental results.

Characterization of recycled crumb rubber modified binders containing wax warm additives

This paper addresses the laboratory experiment of performance properties of recycled CRM binders containing artificially aged CRM binders with wax additives. The warm CRM binders were produced using two wax additives （LEADCAP and Sasobit） and then shortterm and long-term aged using the rolling thin film oven （RTFO） and pressure aging vessel （PAV） procedures. The recycled CRM binders were aged through the RTFO and PAV pro- cedures. A set of Superpave binder tests were carried out on the binders through the rotational viscometer, the dynamic shear rheometer （DSR）, and the bending beam rheometer （BBR）. In general, the results of this study indicated that （1） the addition of longterm aged （LTA） CRM binder can significantly increase the viscosity of the recycled CRM binders as expected, （2） the wax additives in recycled CRM binders were still effective to improve the viscosity and rutting properties even after experiencing the aging process, （3） the CRM binders containing wax additives showed the higher rutting resistance compared to the control CRM binders, （4） the recycled CRM binder containing wax additives was found to have less resistance to fatigue and low temperature cracking, （5） wax warm additives into the recycled CRM binders seemed to have a significant role for cracking properties, based upon their substantial amount.

Analysis of Dielectric and Electro-optic Responses of Nanomaterials Doped Ferroelectric Liquid Crystal Mixture

Dielectric and rotational viscosity measurements of a multi-component ferroelectric liquid crystal mixture were performed by adding a small concentration （0.01 wt%） of silica and multi walled carbon nanotubes （MWCNTs）. Liquid crystals turn out to be outstanding hosts for nanomaterials. A remarkable increase in the rotational viscosity was noticed in CNT doped system as compared to silica doped same liquid crystal system. Comparison of dielectric studies shows higher value of permittivity and dielectric losses for silica-doped sample than those of CNT doped sample. The results have been interpreted both experimentally and theoretically.