物理最新文献

A generalised relativistic transformation for thermodynamic variables is derived in this study using the basic energy–momentum relationship of special relativity. We posit that momentum undergoes changes akin to a time coordinate and treat it as a thermodynamic potential analogous to energy potential. Additionally, we presume that momentum transforms similarly to a time coordinate. We analyse two mutually exclusive conditions to simplify generalised transformations. In one condition, the transformations are as follows: volume ( V = gamma V' ), internal energy ( U = gamma U' ), temperature ( T = gamma T' ) and pressure ( P = P' ), where ( gamma ) represents the Lorentz factor. The primed variables correspond to the moving frame, while the unprimed variables correspond to the stationary frame. The other condition yields ( V = V'/gamma ), ( U = U'/gamma ), ( T = T'/gamma ), ( P = P' ). Since the first law of thermodynamics is an energy conservation statement and Maxwell and other thermodynamic relationships are mathematical constructs based on the first law, it is expected that such relationships should remain invariant in all frames for relativistic thermodynamic transformations. We demonstrate that the ideal gas equation, Maxwell relationships and other thermodynamic relationships (for example, ( (partial U/partial V)_T = -P + T(partial P/partial T)_V )) remain invariant under these two sets of transformations. Furthermore, we show that, although the ideal gas equation and Maxwell relationships remain invariant for many transformations reported earlier, ( (partial U/partial V)_T = -P + T(partial P/partial T)_V ) remains invariant only for the Sutcliffe transformation (( V = V'/gamma ), ( U = gamma U' ), ( T = gamma T' ), ( P = gamma ^2 P' )). We establish that when ( U ), heat ( Q ) and work ( W ) transform similarly, all thermodynamic relationships remain invariant, and such a formalism is mathematically consistent.

The MAXED and GRAVEL unfolding algorithms have been used to determine cross-sections, with the NAXSUN method developed at JRC-Geel. This study explores the potential of a particular type of artificial neural network, the multilayer perceptron (MLP), as an alternative to traditional unfolding algorithms. By generating a training dataset using the TALYS 2.0 code and testing the MLP model on real experimental data, we compared the effectiveness of MLP in unfolding neutron-induced reactions cross sections involving indium and rhenium isotopes. The results were benchmarked against those obtained using standard unfolding algorithms and TALYS 2.0 simulations, demonstrating the advantages and limitations of the ANN approach. The obtained results show a much-reduced corridor of uncertainty in the derived cross-section curves compared to previous work using traditional unfolding techniques.

The assumption of a flat Universe that follows the cosmological principle, i.e., that the universe is statistically homogeneous and isotropic at large scales, comprises one of the core foundations of the standard cosmological model – namely, the (Lambda )CDM paradigm. Nevertheless, it has been rarely tested in the literature. In this work, we assess the validity of this hypothesis by reconstructing the cosmic curvature with currently available observations, such as Type Ia Supernova and Cosmic Chronometers. We do so by means of null tests, given by consistency relations within the standard model scenario, using a non-parametric method – which allows us to circumvent prior assumptions on the underlying cosmology. We find no statistically significant departure from the cosmological principle and null curvature in our analysis. In addition, we show that future cosmological observations, specifically those expected from Hubble parameter measurements from redshift surveys, along with gravitational wave observations as standard sirens, will be able to significantly reduce the uncertainties of current reconstructions.

Zn_1−xMg_xO semiconductor film has been widely applied in the optical, electronic and optoelectronic field, due to the excellent transmittance, adjustable band gap, and environmental friendliness. Herein, Zn_1−xMg_xO films with different x values were fabricated by plasma-enhanced atomic layer deposition (PEALD). The effects of Mg doping content (x value) on the structural, optical and electrical properties of Zn_1−xMg_xO were systematically investigated. As the increase of Mg doping content, the crystallization and the average grain size of Zn_1−xMg_xO film show the first increasing and then decreasing trend. The absorption edge is shifted towards the direction of shorter wavelength, and the band gap is widened, with the increase of Mg doping content. The resistivity value of film enlarges with the increase of Mg doping content. The energy of conduction band minimum (E_CBM) of Zn_1−xMg_xO is elevated by Mg doping. As the buffer layer for CZTSSe, a suitable conduction band offset can be simply obtained. Therefore, the properties of Zn_1−xMg_xO can be accurately adjusted via controlling the Mg doping content.

The self-assembly of water droplet patterns formed on a cold surface through the breath figure technique is ideally hexagonal. However in nature, the surfaces are not smooth which influences the self-assembled droplet pattern. The roughness of the substrate, the use of vapors other than water, the type of the polymer, and concentration of polymer used lead to a distortion in ideal patterns. Taking forward studies on the formation of breath figures by non-aqueous vapor environments, we report the formation of breath figures over polystyrene of molecular weights 35 K, 192 K, and 280 K with the binary mixture of ethanol and propanol (over the entire concentration range) as the condensing drops on smooth and grooved surfaces. Relatively ordered honeycomb patterns are observed on smooth while distorted patterns are observed on the grooved surfaces. The degree of order of breath figure patterns is characterized using Voronoi entropy. It is observed that the pore diameters increase both with the molecular weight and the weight percentage of the polymer. In addition, water contact angle measurements on the patterned surfaces show them to be hydrophobic with a Cassie-Baxter state of wetting.

Graphic abstract

We formulate and numerically solve the Dokshitzer–Gribov–Lipatov–Altarelli–Parisi (DGLAP) evolution equations at next-to-leading order in perturbation theory directly for a basis of 6 physical, observable structure functions in deeply inelastic scattering. By expressing the evolution in the physical basis one evades the factorization scale and scheme dependence. Working in terms of observable quantities, rather than parametrizing and fitting unobservable parton distribution functions (PDFs), provides an unambiguous way to confront predictions of perturbative Quantum Chromodynamics with experimental measurements. We compare numerical results for the DGLAP evolution for structure functions in the physical basis to the conventional evolution with PDFs.

Electromagnetic plates can be used to heat milk and other dairy products rapidly and uniformly. The use of electromagnetic fields enables precise thermal control, which is crucial for safe pasteurization while retaining the nutritional and sensory qualities of milk. This study investigates the dynamics of Ag-ZnO/milk under electromagnetic fields generated by Riga plates with exponentially decaying wall temperatures. The model includes radiation heat emission, heat sinks, and Darcy drag forces due to the porous medium. The flow is mathematically depicted through unsteady partial differential equations solved using the Laplace transform approach. Results include tabulated and graphical with an exhaustive analysis of flow entities against model parameters. Findings highlight increased milk velocity with a boosted modified Hartmann number and declined velocity with wider electrodes. An AI-powered computing approach enhances the accuracy in envisaging flow metrics, achieving 100% accuracy in training, testing, and validation phases. This research not only advances dairy processing technologies but also paves the way for innovations in food safety, nano-enhanced dairy production, and sustainable manufacturing practices.

Graphical abstract

Recently the asymptotic lattice spacing dependence of spectral quantities in lattice QCD has been computed to (textrm{O}(a^2)) using Symanzik Effective theory (Husung et al. in Phys Lett B 829:137069, 2022; Husung in Eur Phys J C 83:142, 2023). Here, we extend these results to matrix elements and correlators of local fermion bilinears, namely the scalar, pseudo-scalar, vector, axial-vector, and tensor. This resembles the typical current insertions for the effective Hamiltonian of electro-weak or BSM contributions, but is only a small fraction of the local fields typically considered. We again restrict considerations to lattice QCD actions with Wilson or Ginsparg–Wilson quarks and thus lattice formulations of QCD without flavour-changing interactions realising at least (textrm{SU}(N_{textrm{f}})_textrm{V}times textrm{SU}(N_{textrm{b}}|N_{textrm{b}})_textrm{V}) flavour symmetries for (N_{textrm{f}}) sea-quarks and (N_{textrm{b}}) quenched valence-quarks respectively in the massless limit. Overall we find only few cases ({hat{Gamma }}), which worsen the asymptotic lattice spacing dependence (a^n[2b_0{bar{g}}^2(1/a)]^{{hat{Gamma }}}) compared to the classically expected (a^n)-scaling. Other than for trivial flavour quantum numbers, only the axial-vector and much milder the tensor may cause some problems at (textrm{O}(a)), strongly suggesting to use at least tree-level Symanzik improvement of those local fields.