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More than 4000 beard samples were collected from a single person every morning over a 12-year period and analyzed using a standard-free method. We detected significant annual variations in the concentrations of magnesium and calcium in the study period, although significant monthly and seasonal variations were not noted. Calcium tends not to be obtained from season-specific foods or drinks, so its variations may be affected by changes in the metabolism of the body. In contrast, however, potassium showed marked long-term variations with significant seasonal differences. As our previous studies confirmed that green vegetables contain large quantities of potassium and that their supply and consumption increase from May to July, the seasonal variations in potassium concentration were attributed to the ingestion of green vegetables. Although magnesium is also contained in green vegetables in large quantities, its principle supply sources are diverse and its concentration did not show any clear seasonal changes.

To evaluate a participatory role of environmental minerals in the pathogenesis of amyotrophic lateral sclerosis (ALS) in the Kii Peninsula of Japan, one of the three high-incidence foci, elemental and neuropathological investigations of lumbar spinal cord and hippocampal tissues were conducted, using particle-induced x-ray emission (PIXE) spectrometry and histomorphometric analysis. The PIXE analysis revealed extremely high contents of Al in both tissues of Kii ALS cases as compared with sporadic ALS and control cases. Morphometric analysis in the hippocampus showed abundant Alzheimer’s neurofibrillary tangles (NFTs) in the Kii ALS cases as compared with the other cases. Al content significantly correlated with the density of NFTs in all ALS cases (r=0.765, p < 0.0001). Interestingly, both Al content and density of NFTs in the hippocampus of all ALS cases significantly and negatively correlated with Ca and Mg contents in the birthplace area’s rivers. The extremely low Ca and Mg content in the focus rivers was confirmed along with the high ratio of Al₂O₃/CaO in the soil. Thus, Kii ALS patients may reflect the geochemical environment of their birthplace, i.e., long term Ca and Mg deficiencies and excess Al accumulation along with widespread NFT formation in the brain.

The electrochemical deposition of magnesium was investigated in ethereal Grignard salt solution with tetraethylammonium bistrifluoro-methanesulfonimidate additive, using cyclic voltammetry, potentiostatic transients, and scanning electron microscope measurements. The voltammograms showed the presence of reduction and oxidation peaks associated with the deposition and dissolution of magnesium. From the analysis of the experimental current transients, it was shown that the magnesium deposition process was characterized as a three-dimensional nucleation. The deposited product obtained from potentiostatic reduction presented a generally uniform and dense film.

An inverse template method that relies on the use of a controlled porous spacer material was implemented to produce periodic magnesium (Mg) foams. Bulk infiltration pressures were varied to determine a processing-property map. The microstructure and mechanical properties of the resulting periodic Mg foams were investigated using optical and scanning electron microscopy (SEM), and compression testing, respectively. SEM was also used to analyze the surface topology of the periodic foams and compare it to the original template material. It was found that the casting pressure has a great effect not only on the success of the infiltration but also the surface roughness and other microstructural features of the foam.

In this study, three types of functionally graded Al₁₈B₄O₃₃/Mg composites which consisted of 2, 3 and 4 layers and where volume fractions of Al₁₈B₄O₃₃ were gradually changing from 0 to 35% were fabricated using squeeze infiltration technique. The mechanical parameters of each layer were measured for the analysis of residual stress. Elastic finite element numerical models were applied to the analysis of thermal residual stress. The analytic results showed that the residual stresses were significantly decreased in the macrointerface with increasing the number of layer.

Magnesium is light, biocompatible and has similar mechanical properties to natural bone, so it has the potential to be used as a biodegradable material for orthopedic applications. However, pure magnesium severely corrodes in a physiological environment, which may hinder its use for in vivo applications. Protective coatings are effective method to delay the corrosion of Mg. In this study, sol-gel and hydroxyapatite (HA) coatings were applied onto the surface of pure magnesium substrates using a biomimetic technique. The corrosion rate of surface-treated substrates was tested. It was found that both types of coatings substantially slowed down the corrosion of the substrate, the 60Ca so-gel and HA coating was more effectively than the 100Si so-gel and HA coating in hindering the degradation of the substrate. Thus, the corrosion rate of magnesium implants can be closely tailored by coating sol-gel then coating apatite thereby monitoring the release of magnesium ions into the body.

Magnesium (Mg) crystal structures are extensively explored using an evolutionary algorithm implemented in the USPEX code. Two structures with simple trigonal and tetragonal symmetries are discovered to possibly exist under high pressure. The stability of these symmetries is determined by elastic constants and phonon spectrum calculations. First-principle calculations are performed to investigate the structural, mechanical and electronic properties of different Mg structures under high pressure (up to 300 GPa). Above 190 GPa, the trigonal structure is more stable than the hexagonal close-packed (HCP) structure. Particularly, the trigonal structure can be considered a compromise between face-centered cubic (FCC) and HCP blocks. Interestingly, the tetragonal structure density is only 95% HCP structure. In addition, the tetragonal structure has strong directional bonding but is less stable than the HCP structure (up to 600 GPa). Pressure significantly changes the electronic properties of both structures although they remain metallic up to 300 GPa.

In this paper, hierarchical surface structures were developed to achieve the superhydrophobicity on AZ31 magnesium alloys. The uniform nodular microstructure was constructed by laser processing, and the subsequent cobalt electrodeposition fabricated a nanostructured needle-like morphology onto the surface nodules. The superhydrophobic surfaces prepared under varied electrodeposition current densities were characterized. When applying 7 mA/cm² current density, the sample revealed the best superhydrophobic performance. The chemical stability of superhydrophobic samples was tested, which confirmed excellent superhydrophobicity was hardly affected by the corrosion environment. The results showed the samples still possessed the hydrophobic ability after tests. The developed fabrication method combines the advantages of laser processing and electrodeposition, which serves as a fast and cost-effective pathway to manufacture superhydrophobic surfaces.

Polycrystalline nickel–zinc ferrites of chemical formula Ni_0.65-xMg_xZn_0.35Fe₂O₄ (x = 0.00 to 0.2 in steps of 0.04) have been prepared by conventional ceramic technique. Calcination and sintering of all samples have been carried out in air atmosphere at 950°C and 1250°C, respectively, followed by natural cooling to room temperature. All the samples were characterized by the X-ray diffraction (XRD) for structure determination. These samples were then investigated for their magnetic and electric properties, including saturation magnetization, Curie temperature, initial permeability measurements and DC electrical resistivity. Porosity was decreased drastically from 15% to 5% showed better quality of the sintered samples. There were increments in initial permeability and DC electrical resistivity throughout the series of samples. Variations in the observed properties as a function of magnesium concentration have been discussed in light of the existing understanding.

The isotope shifts of the $2s{}^2{\mathrm{\text{S}}}_{1/2}$–$2p{}^2{\mathrm{\text{P}}}_J(J=1/2,3/2)$ transitions for the Li-like neutron-rich and neutron-deficient ${}^{21\text{–}32}\mathrm{\text{Mg}}$ isotopes are calculated using the multi-configuration Dirac–Hartree–Fock (MCDHF) method and the relativistic configuration interaction approach. The results provided herein can be employed for the consistency check with the nuclear root-mean-square (rms) nuclear charge radii of the short-lived magnesium isotopes from the experimental isotope shifts using the corresponding transitions. The methods used here could also be applied to other few-electron Li-like systems and the analogous isotope shift results could be obtained.

This work focuses on the analytical study of mechanical and thermal properties of a nanocomposite that can be obtained by reinforcing graphene in magnesium. The estimated mechanical and thermal properties of graphene–magnesium nanocomposite are much higher than magnesium and other existing alloys used in aerospace materials. We also altered the weight percentage of graphene in the composite and observed mechanical and thermal properties of the composite increase with increase in concentration of graphene reinforcement. The Young’s modulus and thermal conductivity of graphene–magnesium nanocomposite are found to be $\ge$165 GPa and $\ge$175 W/mK, respectively. Nanocomposite material with desired properties for targeted applications can also be designed by our analytical modeling technique. This graphene–magnesium nanocomposite can be used for designing improved aerospace structure systems with enhanced properties.

In this paper, kappa and Druyvesteyn distributions of electronic velocity are discussed for non-Maxwellian distribution. For accurate temperature and electron density diagnostics of Magnesium plasma, for the Magnesium VIII ${}^2{P}_{1/2}^0$ to ${}^2{P}_{3/2}^0$ transitions, we calculate kappa averaged collision strengths for $\kappa$ = 2, 3 and 5 and the Druyvesteyn averaged collision strengths for $x$ = 1.5, 2 and 3, for temperature between $5\times 10^4$ and $2.5\times 10^5\mathrm{\text{K}}$. Results indicate that the kappa averaged collision strengths are slightly larger than those for the Maxwellian distribution, and the Druyvesteyn averaged collision strengths are slightly smaller than those for the Maxwellian distribution, furthermore, the averaged collision strengths will be close to those for Maxwellian distribution with increasing $\kappa$ for the kappa distribution and with decreasing $x$ for the Druyvesteyn distribution. The excitation rate coefficients are also calculated for Maxwellian and non-Maxwellian distributions. This discussion will be significant in study of plasma for the non-Maxwellian distribution.

Recent developments in the field of manufacturing techniques and alloy development of light materials are reviewed. In the field of manufacturing Aluminium based components, special attention is given to casting, including liquid forging and semi-solid forming technology while for sheet metal forming technology the focus is on material properties and process technology in superplastic forming. For the manufacturing of Magnesium-based components, special attention is given to casting processes and alloy development for casting. For wrought Magnesium, material properties control is covered. For Titanium-based components, an overview of the latest additions to high strength alloys are given, including non-linear elasticity as demonstrated by materials like GUM Metal™. Advanced forming technology such as Levi Casting are also treated.

The teeth of Evenchinus chloroticus are not only vital tools for their survival but also have fascinating structures in the world of science and engineering. Despite being compositionally similar to rocks, these teeth are still able to scrape along the hard surfaces of rocks for food, while having the unique ability to self-sharpen. Yet these abilities arise from the properties of the teeth, which are in turn dependent on their design and composition. Nanoindentation was used in this study to characterise the hardness across the sea urchin tooth in detail. It focuses on the chewing tip since the main grinding function is performed by this region. In addition, SEM and EDS were used to explore any correlations between the mechanical properties of the tooth and its composition. It was found that there were two main relatively hard regions (stone part in the centre of the top flange part and another similar region in the centre of the bottom keel zone). These regions are similar in structure, consisting of thin needles and matrix and have a higher magnesium content compared to other areas of the tooth, which is attributed to the greater proportion of matrix present. Furthermore, the regions below the stone part and at the start of the keel zone appear to be weaker, which might be due to the significant amount of pores in these areas. The sharp tip is maintained by shedding of the primary plates surrounding the stone part and the keel fibres, leaving only the stone part at the chewing tip.

This study examined the microstructure and high temperature tensile properties of Mg-5Sn-3Al-1Zn-xCe (x=0, 0.5 and 1.0 wt.%) alloys. The alloys were melted in a steel crucible under a CO₂+SF₆ atmosphere and poured into a preheated permanent mold at 200°C. The microstructure of the Mg-5Sn-3Al-1Zn alloy consisted mainly of α-Mg, Mg₁₇Al₁₂ and Mg₂Sn phases. With increasing Ce content, an Al₁₁Ce₃ phase was newly formed on the grain boundaries. The results showed the tensile strength at room temperature decreased with increasing Ce content but increased at elevated temperatures.