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This work explores the thermophysical properties of the SPC/E model of water at temperatures between 250 and 400 K and at pressure from 0.1 to 1000 MPa. From a series of Molecular Dynamics simulations (in the NPT ensemble and also in the NVT ensemble), the constant pressure and constant volume heat capacity, the isobaric expansion coefficient, the isothermal compressibility, and the speed of sound are obtained from fluctuation formulas and thermodynamic numerical derivatives and compared with available experimental data. [Display omitted] • Thermophysical properties of water over a wide temperature and pressure range. • Confrontation of a common water model with experimental results. • Benchmark data for molecualr dynamics simulations. [ABSTRACT FROM AUTHOR]

This article presents the results of tests conducted on a measuring system for monitoring changes in the distribution of temperature in a coal deposit during the heating and cooling phases, and their correlation with the analysis of the concentration of gases. The tests were conducted on five samples of hard coal collected in deposits mined in Poland. Measurements of the changes in temperature and changes in gas concentration were conducted from the temperature of 35 to 300 °C, for the heating phase, and from 300 to 35 °C, for the cooling phase. The percentage share of coal of given temperatures was calculated. When comparing the percentage share for the same temperature in the hot spot, for the heating and cooling phase, significant differences in the distribution of the given percentages were observed. Changes in gas concentrations during heating and cooling were analyzed and the dynamics of changes in gas concentrations were determined for the coals tested. Changes in the values of fire hazard indices were analyzed. There were significant differences in the concentration of gases and the values of fire hazard indices between the heating and the cooling phase. The application of different criteria to assess coal during heating and cooling was proposed. [ABSTRACT FROM AUTHOR]

We report new experimental data of the ultrasonic measurements in three ionic liquids with triflate anion: 1-ethylpyridinium triflate, 1-butyl-3-methylimidazolium triflate, diethylmethylammonium triflate. The speed of sound was determined in the temperature range of (297 – 374) K and the pressure range of (0. 1 – 196. 2) MPa. In addition, the respective densities in this range were found using the acoustic route. For the first two substances, the effect of pressure-induced solidification is detected. It is shown that the high-pressure data on the sound velocity can be accurately predicted by applying the pressure fluctuation theory-based model using parameters, which requires only the data determined at the ambient atmospheric pressure. In turn, the density can be predicted using the Fluctuation Theory-based Equation of State (FT-EoS), which includes the isothermal nonlinearity parameter, which is argued as related to the frequency of interparticle oscillations. This interdependence is confirmed by the comparative analysis with the respective peak in the low-frequency Raman–Kerr spectrum. • The speed of sound is measured and the density is determined to 196. 1 MPa. • Pressure-induced freezing of ionic liquids at macroscopic volumes is detected. • Interplay of thermodynamics and microscopic interparticle oscillations is discussed. [ABSTRACT FROM AUTHOR]

In this work, we investigated individual bacteria M. tuberculosis belonging to strains of the Beijing family with different drug sensitivity (sensitive, multi and extensive drug-resistant) by surface-enhanced Raman spectroscopy (SERS) in the fingerprint region. The latter is focused on the spectral bands, which correspond to a set of glutathione bands and DNA methylation patterns revealed due to 5-methylcytosine spectral biomarkers. It is shown that these spectral features can be correlated with drug sensitivity and DNA methylation. Thus, since this kind of diagnostics is fast and operates with individual cells, it can be considered a promising tool, which significantly shortens the time required for a strain's type identification necessary to prescribe adequate therapy., Competing Interests: The authors declare that they have no competing interests., (© 2025 Zyubin et al.)

We consider subdiffusive motion, modeled by the generalized Langevin equation in an equilibrium setting, of tracer particles in channels of indefinite length in the x direction: the channels of varying width and the channels with sinusoidally meandering midline. The subdiffusion in the x direction is not affected by constraints put by the channel. This is especially astonishing for meandering channels whose centerline might be quite long. The same behavior is seen in a holonomic model of a bead on a sinusoidal and meandering wire, where some analytic insights are possible.

During this work, we demonstrate, for the first time, that the volumetric properties of pure ionic liquids could be truly predicted as a function of temperature from 219 K to 473 K and pressure up to 300 MPa. This has been achieved by using only density and isothermal compressibility data at atmospheric pressure through the Fluctuation Theory-based Tait-like Equation of State (FT-EoS). The experimental density data of 80 different ionic liquids, described in the literature by several research groups as a function of temperature and pressure, was then used to provide comparisons. Excellent predictive capability of FT-EoS was observed with an overall relative absolute average deviation close to 0.14% for the 15,298 data points examined during this work.