A multilayered hybrid Al1050/AZ31/Al1050 alloy was fabricated by cross-accumulative roll bonding (CARB) up to 5 cycles at 400 °C. Microstructure, anelastic, and mechanical properties were characterized using scanning electron microscopy (SEM), internal friction (IF) measurements, and tensile tests, respectively. The thickness of AZ31 layers of the initial sample gradually loses its continuity in the form of localized necking and fragmentation and reduces to less than 150 µm after the fifth cycle and, contrarily, that of the Al1050 layer increases. Hot CARB processing causes an enhanced formation of intermetallic compounds. For almost all the cycles, apart from N = 1, the ultimate tensile strength of the sandwich measured in the transverse direction is comparable to that of the rolling direction. A maximum value of 182 MPa is achieved after one cycle in the transverse direction and a ductility of 9
This study is devoted to the preparation of a Ni–Al alloy (32 at.
We present a complete dataset of collision cross sections for proton-helium interactions across the sub-relativistic energy range, from very-low energies (10(-4) eV) up to at least 500 keV. The dataset includes elastic scattering (using quantal methods), charge transfer (quantum-mechanical molecular orbital close-coupling method), single ionization (Improved Empirical Formula for K-shell ionization model), and 23 electronic excitations (SE2PEAK model) up to principal quantum number n = 5. While momentum-transfer cross sections given in the literature vary between 0.1 and 10(4) eV, the present work extends the energy range down to 10(-3) eV up to 500 keV and, crucially, integrates these elastic data within a unified framework that includes major inelastic channels-especially state-resolved excitation to triplet states (n = 2-4), which are absent in prior datasets. This full set of elastic and inelastic cross sections is then used as input for optimized Monte Carlo simulations to calculate transport and reaction coefficients for protons in helium over a wide range of reduced electric fields (E/N) from 0.1 to 10(4) Td. The resulting proton transport data are compared with electron transport data in helium calculated from a multi-term solution of the Boltzmann equation over the same E/N range. The comparison highlights the expected significant differences in the behavior of protons and electrons, primarily due to their mass disparity and distinct collision cross sections. The calculated transport coefficients (drift velocity or mobility, and transversal and longitudinal diffusion coefficients) and macroscopic collision frequencies for protons are presented vs E/N, revealing the dominant role of elastic collisions and charge transfer at low E/N and the onset of inelastic processes at higher values. These transport and reaction coefficients, given for the first time in the literature for such E/N range, provide a robust foundation for advanced electrodynamic modeling of electron-proton plasmas in helium, relevant for applications, such as fusion edge plasmas or electric plasma propulsion.
Ground-nesting shorebirds face growing pressure from recreational activities in coastal urban areas. We monitored the breeding success of Kentish Plover (Charadrius alexandrinus) and Little Ringed Plover (Charadrius dubius) over six consecutive years (2020-2025) at the Promenade of Sablettes, a heavily visited waterfront in Algiers, Algeria. We combined field surveys with multi-sensor remote sensing analysis using Sentinel-1, Sentinel-2, and Dynamic World data to quantify habitat change. A total of 105 nests were recorded across both species. Breeding success reached 70% during the COVID-19 lockdown period (2020-2021), when human visitation dropped sharply. In contrast, complete reproductive failure occurred in 2022 and 2023, coinciding with resumed tourism and unplanned construction activities. Remote sensing revealed that 80-85% of the study area experienced severe habitat degradation between 2020 and 2025, while suitable refuge zones shrank to less than 10% of the total surface. Fledged chicks consistently moved toward a less disturbed vegetated zone, highlighting its functional importance for brood survival. Our results show that human disturbance is the primary factor limiting breeding success at this site, operating through two pathways: direct disturbance of nesting birds and progressive habitat degradation driven by recreational use and unplanned construction. When disturbance was reduced during the pandemic, the habitat proved fully functional for both species. These findings suggest that simple management measures such as seasonal access restrictions and symbolic fencing during the April-July breeding period could restore breeding conditions without major habitat engineering. This study provides one of the first integrations of long-term field breeding data with landscape-scale remote sensing to document the effects of the anthropause and subsequent recovery on urban shorebird populations.
In this paper, we investigate the strong uniform consistency rate of the Nadaraya-Watson (NW) kernel regression estimator under a widely orthant dependence model. The performance of the proposed estimator is illustrated through some simulations. Furthermore, a large comparison study with other NW estimators is presented based on the selected bandwidth type, and the performance of these NW estimators is evaluated using the global mean squared error (GMSE) criterion. Moreover, a real data analysis is provided to support the theoretical results.
