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This study investigates the impact of structural configurations, boundary conditions, and atomic number on the Curie transition temperature ($T_c)$ of bulk cobalt (Co) utilizing Monte Carlo simulations. The analysis reveals that the Curie temperature increases as the structure transitions from a simple cubic (SC) to a body-centered cubic (BCC), hexagonal close-packed (HCP), and face-centered cubic (FCC) configuration. The SC structure, exhibiting the lowest $T_c$, serves as the reference for evaluating these influencing factors. The study also demonstrates that nonperiodic boundary conditions yield the lowest $T_c$ compared to periodic ones. Additionally, an increase in the number of atoms from 4000 to 108,000 under nonperiodic boundary conditions correlates with an increase in $T_c$. These findings are consistent with experimental data and provide a foundational basis for researchers involved in the synthesis and application of bulk Co in devices, biomedical applications at room temperature, and emerging technologies.

This paper studies the effects of heating rate 4 × 10${}^{11}$ K/s, 4 × 10${}^{12}$ K/s, 4 × 10${}^{13}$ K/s; impurity concentration of Cu on Ni${}_{1-x}$Cu${}_x$ bulk with x = 0.1, x = 0.3, x = 0.5, x = 0.7; atom number (N), N = 4000 atoms, 5324 atoms, 6912 atoms, 8788 atoms at temperatures (T), T = 300 K; N = 6912 atoms at T = 300 K, 400 K, 500 K, 600 K, 700 K, 800 K; N = 6912 atoms at T = 600 K after time annealing temperature (t), t = 500 ps on the structure, crystallization temperature and crystallization process of Ni${}_{1-x}$Cu${}_x$ bulk by molecular dynamics (MD) method with interactive embedding Sutton–Chen (ST) and periodic boundary conditions. The structural characteristics were analyzed through radial distribution function (RDF), energy total (E${}_{\mathrm{\text{tot}}}$), size (l) and common neighborhood analysis (CNA) method; temperature (T), crystallization temperature (T${}_g$), crystallization process through relationship between E${}_{\mathrm{\text{tot}}}$, T. The results showed Ni${}_{1-x}$Cu${}_x$ bulk and links Ni–Ni, Ni–Cu, Cu–Cu always exist in 03 types structures: FCC, HCP, Amor. When time annealing temperature increases then Ni${}_{1-x}$Cu${}_x$ bulk moves from a crystalline state to an amorphous state. When increases impurity concentration of Cu in Ni${}_{1-x}$Cu${}_x$ bulk, then the structure unit number FCC, HCP decreases and then increases, structure unit number Amor increases and then decreases. When atom number (N) increases, decreasing T and increasing time annealing temperature lead to structure unit number FCC, HCP increases, Amor decreases and structural, crystallization temperature, crystallization process of Ni${}_{1-x}$Cu${}_x$ bulk change.

Nowadays, the pacific use of ionizing radiation has attracted a great deal of attention in medicine, as well as in radiodiagnostic, and radiotherapy. However to avoid unnecessary irradiations to the healthy tissue, a strict quality control is required. This has led to the development of a new dosimeter equivalent to the tissue that could be highly suitable for the radiation dosimetry. The borate of magnesium with its low effective atomic number (Z_eff), is considered equivalent to the human-tissue. For this reason, in this work, we present the results obtained of the thermoluminescent characterization of this material. The test that was carried out includes the lower detection limit, sensitivity, reproducibility of the TL measurement, stability of information (fading), and TL response as a function of the delivered dose and energy response, which are recommended by the International Commission on Radiological Units and Measurements (ICRU) and International Commission on Radiological Protection (ICRP). Two different concentrations of Dy activator were used i.e. 1.25 (batch A) and 1.5 (batch B) mol%. Meanwhile, the Na activator was 0.5 mol% in both cases. The results show that this new thermoluminescent material is adequate for radiation dosimetry in different medical applications.

In this study, efforts were made to propose a semi-empirical equation for electron capture within the atomic number range $7\le Z\le 103$ and the mass number range of $12\le A\le 252$. About 753 nuclei were considered for the same. These nuclei were categorized into four groups based on the parities of both protons and neutrons: even(Z)–even(N), even(Z)–odd(N), odd(Z)–even(N) and odd(Z)–odd(N). Comparative analysis was carried out between the formula’s predictions and experimental data. The improved semi-empirical formula for electron capture belongs to the first category, requiring only the daughter nucleus’s atomic number and decay energy, making them a valuable tool for predicting electron capture half-lives. The present formula effectively describes even-Z-even-N cases. However, significant discrepancies occur when either Z or N is odd in nuclei, indicating that further refinement is necessary to improve.

Based on the experimental maximum escape depth $S(W_{\mathrm{\text{p0}}}$, $Z)$ of rediffused electrons from atomic number $Z$ metal at incident energy of primary electron $W_{\mathrm{\text{p0}}}$, the relationship among $S(W_{\mathrm{\text{p0}}}$, $Z)$, $W_{\mathrm{\text{p0}}}$ and $Z$ in the energy range of 9.3keV$\leqq W_{\mathrm{\text{p0}}}\leqq$40keV was obtained and proved to be true by experimental data. According to the experimental results of rediffused electrons, the characteristics of secondary electron emission, relationships among parameters of rediffused electrons and the main processes of rediffused electrons emission, the formula for $W_{\mathrm{\text{p0}}}$ backscattering coefficient $\eta (W_{\mathrm{\text{p0}}}$, $Z$, $t)$ of $Z$ metal films with film thickness $t$ as a function of $t$, Z and was deduced, and the results were analyzed. It is concluded that the deduced formula for $\eta (W_{\mathrm{\text{p0}}}$, $Z$, $t)$ can be used to calculate $\eta (W_{\mathrm{\text{p0}}}$, $Z$, $t)$ in the energy range of 9.3keV$\leqq W_{\mathrm{\text{p0}}}\leqq$40keV. The secondary electron yield $\delta$ from thin films are applied in more and more fields such as electronic information technology, accelerator and space flight, and $\eta (W_{\mathrm{\text{p0}}}$, Z, $t)$ is an important parameter of $\delta$ from $Z$ metal films. So deducing the formula for $\eta (W_{\mathrm{\text{p0}}}$, $Z$, $t)$ in this study is necessary.

Some people think that carbon and sustainable development are not compatible. This textbook shows that carbon dioxide (CO₂) from the air and bio-carbon from biomass are our best allies in the energy transition, towards greater sustainability. We pose the problem of the decarbonation (or decarbonization) of our economy by looking at ways to reduce our dependence on fossil carbon (coal, petroleum, natural gas, bitumen, carbonaceous shales, lignite, peat). The urgent goal is to curb the exponential increase in the concentration of carbon dioxide in the atmosphere and hydrosphere (Figures 1.1 and 1.2) that is directly related to our consumption of fossil carbon for our energy and materials The goal of the Paris agreement (United Nations COP 21, Dec. 12, 2015) of limiting the temperature increase to 1.5 degrees (compared to the pre-industrial era, before 1800) is becoming increasingly unattainable (Intergovermental Panel on Climate Change (IPCC), report of Aug. 6, 2021). On Aug. 9, 2021 Boris Johnson, prime minister of the United Kingdom, declared that coal needs to be consigned to history to limit global warming. CO₂ has an important social cost…