Cornelia Breitkopf

Achieving a unified description of interactions remains an open challenge in theoretical physics, which currently describes four fundamental forces. This situation may be viewed differently when interactions are formulated in terms of processes (work as actio ) rather than forces (force as actio ), not only at the macroscopic level but also at the quantum level. This paper contrasts force‐based and work‐based approaches to interaction and we argue that acting forces serve as a geometric surrogate rather than as an explicit representation of the underlying simultaneous processes. Simple examples – such as lifting, acceleration, and displacement of a body, as well as processes involving quantum objects – are used to illustrate the applicability of process equations, including that form of work describing a change in the momentum of a body or particle. The results suggest that a work‐based approach to interactions is a serious alternative to the force‐based one and could pave the way toward a deterministic formulation of quantum theory.

Effective thermal management in polymeric materials still represents a considerable challenge for emerging applications, such as wearable electronics, soft robotics, and sustainable composite systems, wherein flexibility and environmental compatibility are of utmost importance. This research utilizes non-equilibrium molecular dynamics (NEMD) simulations to examine interfacial thermal resistance (ITR) and effective thermal conductivity (keff) in bio-based PBS-ENR-PBS trilayer systems. Two varieties of epoxidized natural rubber, ENR-25 and ENR-50, with varying epoxide concentrations, are analyzed to clarify the influence of interfacial polarity and chemical reactivity. Interfacial heat transmission is systematically adjusted by including covalent transesterification crosslinks at the PBS-ENR interface, with concentrations ranging from 0 to 50%. Steady-state temperature profiles, heat fluxes, and density-based interface detection are employed to quantify layer-specific conductivities, interfacial temperature discontinuities, and total thermal resistance. The findings indicate that moderate crosslinking significantly improves interfacial phonon coupling and diminishes ITR in ENR-25 systems, but excessive crosslinking results in saturation due to constrained chain mobility. Conversely, ENR-50 demonstrates a faster onset of transport saturation due to its elevated inherent polarity and stiffness. The findings indicate that effective thermal transfer in soft, bio-based polymer interfaces results from a balance of molecular connection and segmental flexibility, offering design principles for thermally efficient elastomeric composites.

The Lorentz transformations of mass and time are derived and explained within the framework of quantum-process thermodynamics. To this end, various notions of quantum work are employed to describe the behavior of an accelerated particle, such as an electron, which consists of a core wave and a guiding wave. We find that, during acceleration, a particle changes not only its velocity but also its internal structure and energies. While the mass and frequency of its guiding wave increase, the mass and frequency of its core wave decrease. As the wavelength of the core wave increases, the rate at which an accelerated atomic clock accumulates time is reduced. This is a dynamical process, rather than an observational effect formulated in terms of relations between inertial frames. We present a new equation for a form of energy that provides a unified description of particle motion and electromagnetic energy. We compare our results with special relativity and discuss a range of microscopic and macroscopic experiments. On this basis, quantum-process thermodynamics emerges as a promising framework for exploring deterministic aspects of quantum dynamics.

Adsorption and diffusion of alkanes in sulfated zirconia are characterized by frequency response and diffuse reflectance infrared Fourier transform spectroscopy.

Cis-1,4-polyisoprene is a widely used elastomer that demonstrates particular thermal and mechanical characteristics, in which the latter is influenced by temperature and strain rate. Molecular dynamic simulations were used to obtain thermal conductivities, glass transition temperatures (T_g), and tensile deformation. Thermal conductivities were calculated by applying the Green–Kubo method, and a decrease in thermal conductivity was observed with increasing temperature. Density–temperature relations were used to calculate T_g, which indicates the transition from the glassy to the rubbery state of the material, and this temperature influences mechanical properties. Investigation of the mechanical properties under uniaxial tensile deformation for constant strain rates indicates an increase in the stiffness and strength of the material at lower temperatures, while increasing molecular mobility at higher temperatures results in reducing these properties. The influence of strain rates at constant temperature highlighted the viscoelastic nature of the structure; increasing strain rates resulted in increases in stiffness, strength, elongation at maximum strength, and elongation at break because of restricted molecular relaxation time. The united-atom force field contributes to higher computational efficiency, which is suitable for large-scale simulations. These results provide important information on the thermo-mechanical properties and tunability of cis-1,4-polyisoprene, which supports applications in the production of interactive fiber rubber composites.

Polymer thermal conductivities play an important role for their potential use in industrial applications. Therefore, great efforts have been made to investigate fundamental structure–property relationships to understand and predict thermal conductivities for polymers and their composites. The review summarizes selected well-proven microscopic theoretical approaches to calculate thermal conductivities such as EMD, NEMD, EMT, and BTE, and cites examples to focus on different qualitative aspects of recent polymer theoretical research. Examples other than polymer materials are given as supplemental information to support the general discussion of heat transport phenomena in solid materials.

The thermal conductivities and glass transition temperatures of polybutadiene crosslinked with randomly distributed sulfur chains having different lengths from mono-sulfur (S1) to octa-sulfur (S8) were investigated. The thermal conductivities of the related models as a function of the heat flux autocorrelation function, applying an equilibrium molecular dynamic (EMD) simulation and the Green–Kubo method, were studied for a wide range of temperatures. The influence of the length of sulfur chains, degree of crosslinking, and molar mass of the crosslinker on the glass transition temperature and final values of thermal conductivities were studied. First, the degree of crosslinking is considered constant for the eight simulation models, from mono-sulfur (S1) to octa-sulfur (S8), while the molar mass of the sulfur is increases. The results show that the thermal conductivities of the crosslinked structure decrease with increasing temperature for each model. Moreover, by increasing the lengths of the sulfur chains and the molar weight of the crosslinker, thermal conductivity increases at a constant temperature. The MD simulation demonstrates that the glass transition temperature and density of the crosslinked structure enhance as the length of the sulfur chains and molar mass of the sulfur increase. Second, the molar weight of sulfur is considered constant in these eight models; therefore, the degree of crosslinking decreases with the increase in the lengths of the sulfur chains. The results show that the thermal conductivities of the crosslinked structure decrease with the increase in the temperature for each model. Moreover, by increasing the lengths of sulfur chains and thus decreasing the degree of crosslinking, the trend in changes in thermal conductivities are almost the same for all of these models, so thermal conductivity is constant for a specific temperature. In addition, the glass transition temperature and density of the crosslinked structure decrease.

Transient uptake curves for propane gas in a bed of HZSM-5 using a volumetric frequency response setup (batch system) were obtained. Thereby, a perturbation, such as a change in volume, was applied to the solid/gas system, and the resulting change in pressure was detected. Two cases of mass transfer limitations (bed diffusion control and micropore diffusion control) were compared, and it was concluded that, in the presented case, micropore diffusion is the rate-determining process. The obtained micropore diffusion coefficient for propane in HZSM-5 was, on average, about 1.2 × 10⁻¹⁰ m² g⁻¹, which is in good agreement with other frequency response studies shown by literature data. The homemade setup and the modeling presented in this work serve as the basis for ongoing numerical simulations.