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This study reports the experimental density and speed of sound data of 1-chlorononane along seven isotherms from 293.15 to 413.15 K at pressures from saturation up to 196.1 MPa. The pertinent isothermal compressibility and isobaric coefficient of expansion data have been obtained by numerical differentiating of densities. In addition, the saturated liquid densities have been measured from 253.15 to 443.15 K, isobaric heat capacities from 248.15 to 448.15 K, and speeds of sound from 246.88 to 457.25 K. These results have been interpolated by polynomials to obtain the saturated liquid isobaric coefficient of expansion, adiabatic and isothermal compressibility, isochoric heat capacity, and internal pressure data. Performances of three predictive approaches having different degrees of complexity, namely the Critical Point-based Perturbed Chain Statistical Association Fluid Theory, the Statistical Association Fluid Theory of Variable Range Mie Potential parametrized by a Corresponding States approach of Mejía et al. (Ind. Eng. Chem. Res. 2014, 53, 4131), and the fluctuation theory-based Tait-like equation of state have been examined. The latter model has a superiority in estimating of the high-pressure data; however, unlike both statistical association fluid theory approaches, it utilizes the saturated liquid data. It has also been demonstrated that all the models successfully predict various phenomena related with replacement of hydrogen by chlorine in n-nonane molecule. [ABSTRACT FROM AUTHOR]

For liquid 1-chloropropane, we report the data of measurement of the density and the speed of sound within the range of temperatures 183.15–373.15 K at atmospheric pressure (up to 313 K) and the saturation conditions for 323.15–373.15 K, the isobaric heat capacity within the range 173.15–298.15 K, and density and the speed of sound under high pressure for the temperatures 294.15–373.15 K evaluated using acoustic piezometer and the pulse-phase echo method for the measurement of the speed of sound. It is shown that that volumetric data under high pressure can be successfully predicted using the fluctuation theory-based Tait-like equation of state, which required a knowledge of data measured at the atmospheric pressure only. The corresponding temperature dependences of parameters are provided. [ABSTRACT FROM AUTHOR]

Thisstudy reports the experimental measurements of speeds of soundfrom 293.15 to 313.15 K and pressures up to 100 MPa in 1,2-dichloroethane,and up to 45 MPa in 1,2-dibromoethane, approaching solidificationof this compound. In addition, new atmospheric pressure data on densitiesof 1,2-dichloroethane from 278.15 to 348.15 K are presented. Theseexperimental data have been implemented for calculating densities,isobaric heat capacities and coefficients of thermal expansion, isentropicand isothermal compressibilities, and internal pressures as functionsof pressure and temperature by using an acoustic method of Davis–Gordon–Sun.Development of a new Design Institute for Physical Properties (DIPPR)-basedversion of the fluctuation theory-based Tait-like equation of state(FT-EoS) is presented. This model could become a simple and reliabletool implementing the DIPPR’s saturated state expressions forpredicting the high-pressure densities and speeds of sound. It hasalso been demonstrated that both compounds under consideration canbe included in the applicability range of the predictive criticalpoint-based perturbed-chain statistical association fluid theory (CP-PC-SAFT)approach employing the DIPPR’s critical constants. In spiteof its poor modeling of vapor pressures of these substances away fromtheir critical points, CP-PC-SAFT appears as a robust estimator ofvarious thermodynamic properties of both pure compounds and mixturesin the entire pressure range, and as well of the high-pressure phaseequilibria. Unlike CP-PC-SAFT, parametrization of PC-SAFT comprisesfitting large experimental databases, and it cannot be implementedfor simultaneous modeling of the critical and the subcritical states.Although this model is the less successful estimator of sound velocitiesand compressibilities, it has a doubtless advantage in modeling thelow-pressure phase equilibria. [ABSTRACT FROM AUTHOR]

Dissociation of a ligand isoniazid from a protein catalase was investigated using all-atom molecular dynamics (MD) simulations. Random acceleration MD (τ-RAMD) was used, in which a random artificial force applied to the ligand facilitates its dissociation. We have suggested a novel approach to extrapolate such obtained dissociation times to the zero-force limit assuming never before attempted universal exponential dependence of the bond strength on the applied force, allowing direct comparison with experimentally measured values. We have found that our calculated dissociation time was equal to 36.1 s with statistically significant values distributed in the interval of 0.2-72.0 s, which quantitatively matches the experimental value of 50 ± 8 s despite the extrapolation over 9 orders of magnitude in time.

Presented here is a comprehensive study on the antioxidant properties of various alcoholic beverages: beers, wines, tinctures, and strong spirits, including whisky, brandy, cognac, vodkas, and liquors. The Trolox equivalent antioxidant capacity (TEAC) of each of these various alcoholic beverages is determined using an electron paramagnetic resonance (EPR) method, which is based on a semiempirical correlation. Moreover, the EC 50 parameter was determined on the basis of the dependences of the TEAC values obtained by this mathematical equation. Moreover, the total phenolic content (TP) and color index, which have a direct influence on the antioxidant properties of the alcoholic beverages, were identified. The results showed that all the investigated alcoholic beverages (ABs), with the exception for vodkas, exhibit antioxidant properties. By performing a statistical analysis, it was found that the TEAC value significantly depends on the TP, production method, and raw material from which the alcohol was made. However, it is assumed that the TEAC value of alcoholic beverages is independent of the alcohol content.