Europium (Eu) doped Calcium borophosphate (CBP) phosphors were synthesized via the solid-state diffusion method. The prepared Europium (Eu) doped Calcium borophosphate (CBP) powder was heated up to 600 ℃ for 6 h for a complete diffusion of ions in the powder system. XRD results showed that the prepared phosphors exhibit a well-crystallized hexagonal phase. The complete diffusion inside the CBP/Eu powder system has been confirmed by the presence of elements such as P, O, Bi, Ca, C, Eu, and B. Apart from that, the synthesized powder system has shown a down-conversion property where the Eu3+-activated ion was excited at 251 nm. Under the excitation of 251 nm, CBP/Eu phosphor showed intense emissions peaking at 591,617, and 693 nm due to the 5D0 → 7F1, 5D0 → 7F2, and 5D0 → 7F4 transition of Eu3+ ions. The obtained results suggest that the CBP/Eu phosphors have the potential for spectral response coating materials to improve photovoltaic (PV) panel efficiency.
Two-dimensional hexagonal boron nitride nanosheets (h-BNNS) were synthesized on silver (Ag) substrates via a scalable, room-temperature atmospheric pressure plasma (APP) technique, employing borazine as a precursor. This approach overcomes the limitations of conventional chemical vapor deposition (CVD), which requires high temperatures (>800 °C) and low pressures (10⁻2 Pa). The h-BNNS were characterized using FT-IR spectroscopy, confirming the presence of BN functional groups (805 cm⁻1 and 1632 cm⁻1), while FESEM/EDS revealed uniform nanosheet morphology with reduced particle size (80.66 nm at 20 min plasma exposure) and pore size (28.6 nm). XRD analysis demonstrated high crystallinity, with prominent h-BN (002) and h-BN (100) peaks, and Scherrer calculations indicated a crystallite size of ~15 nm. The coatings exhibited minimal disruption to UV-VIS reflectivity, maintaining Ag’s optical properties. Crucially, Vickers hardness tests showed a 39% improvement (38.3 HV vs. 27.6 HV for pristine Ag) due to plasma-induced cross-linking and interfacial adhesion. This work establishes APP as a cost-effective, eco-friendly alternative for growing h-BNNS on temperature-sensitive substrates, with applications in optical mirrors, corrosion-resistant coatings, energy devices and gas sensing.
The chemical reinforcement of sandy soils is usually carried out to improve their properties and meet specific engineering requirements. Nevertheless, conventional reinforcement agents are often expensive; the process is energy-intensive and causes serious environmental issues. Therefore, developing a cost-effective, room-temperature-based method that uses recyclable chemicals is necessary. In the current study, poly (styrene-co-methyl methacrylate) (PS-PMMA) is used as a stabilizer to reinforce sandy soil. The copolymer-reinforced sand samples were prepared using the one-step bulk polymerization method at room temperature. The mechanical strength of the copolymer-reinforced sand samples depends on the ratio of the PS-PMMA copolymer to the sand. The higher the copolymer-to-sand ratio, the higher the sample’s compressive strength. The sand (70 wt.%)-PS-PMMA (30 wt.%) sample exhibited the highest compressive strength of 1900 psi. The copolymer matrix enwraps the sand particles to form a stable structure with high compressive strengths.
Publications overestimating the medical and ecological sequels of a slight anthropogenic increase in the radiation background have been reviewed recently with examples of different organs and pathological conditions. The overestimation contributed to the strangulation of atomic energy. The use of nuclear energy for electricity production is on the agenda today due to the increasing energy needs of humankind. Apparently, certain scientific writers acted in the interests of fossil fuel producers. Health risks and environmental damage are maximal for coal and oil, lower for natural gas, and much lower for atomic energy. This letter is an addition to previously published materials, this time focused on studies of cataracts in radiation-exposed populations in Russia. Selection and self-selection bias are of particular significance. Apparently, the self-reporting rate correlates with dose estimates and/or with professional awareness about radiation-related risks among nuclear workers or radiologic technologists, the latter being associated with their work experience/duration and hence with the accumulated dose. Individuals informed of their higher doses would more often seek medical advice and receive more attention from medics. As a result, lens opacities are diagnosed in exposed people earlier than in the general population. This explains dose-effect correlations proven for the incidence of cataracts but not for the frequency of cataract surgeries. Along the same lines, various pathological conditions are more often detected in exposed people. Ideological bias and the trimming of statistics have not been unusual in the Russian medical sciences. It is known that ionizing radiation causes cataracts; however, threshold levels associated with risks are understudied. In particular, thresholds for chronic and fractionated exposures are uncertain and may be underestimated.
Knowledge of the presence of heavy metals in soils of agricultural areas is important to prevent their accumulation in cultivated plants. The objective of the present investigation was to evaluate the total concentrations and fractions of heavy metals Cd, Pb, Zn, Fe, Mn, Ni, Cu, Cr and Co in the tobacco-growing area of Pinar del Río, Cuba and their relationship with the physicochemical properties of soil. For the study, 59 samples of three types of soils were collected at 20 cm depth. The pseudo-total concentrations of metals in the soils are low and lower than the prevention values registered for Cuban soils. In general, the heavy metals studied present a high affinity for the most stable fractions of the soil, which means a low risk of transfer to the tobacco crop or accumulation in groundwater. The pseudo-total concentrations of heavy metals were low, below the alert values established for soils in the region. The heavy metals studied were mainly associated with the residual fraction, the second fraction with the highest association with metals was that linked to manganese and iron oxides. The principal component analysis showed that their main source is pedogenetic and that these elements are closely related to cation exchange capacity and calcium content.
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