Calcium is the most prominent mineral in bone which determines the risk of osteoporosis. Atomic mineral is the smallest component of trabecular bone. Trabecular bone is more sensitive to hormones or other biological factors that are involved in modulating bone metabolism. Both of these substances also show the mechanical strength of the bone. Organic and inorganic components are responsible for toughness and rigidity of bone, respectively. White paper from Indonesian Osteoporosis Association shows that prevalence of osteoporosis at 2007 was 28.85% for man and 32.3% for woman. The prevalence of osteoporosis in South East Asia was estimated of about 15.3%. A few studies focusing on osteoporosis epidemiology in less developed or developing countries make the prevalence unclear. This condition is caused by abnormalities of bone density and bone microstructure. Introductionĭecreasing of skeletal strength and increasing of fragility and fracture risk was a marker of osteoporosis. Among these atoms, known to have important roles in bone structure, we found involvement of atomic mineral and calcium which are considerable to contribute to osteoporotic phenomena. Conversely, concentrations of Na, Mg, P, K, Ca, Cr, Pd, Ag, Mn, Fe, Cu, Zn, Rb, Sr, Pb, and Se are lower in osteoporosis than in normal bones. These atomic minerals have negative role to imbalance between bone resorption and bone formation activity. The results showed that the concentration of B, Al, S, V, Co, Mo, Te, Ba, La, Ni, As, and Ca/P ratio is higher in osteoporosis than normal. Inclusion criteria of bone samples consist of postmenopausal woman, trabecular bone fracture, normal and osteoporosis BMD value, and no history of previous disease. The influence of these elements on bone metabolic processes is also discussed. Thus, in this report, the difference of metallic and nonmetallic elements in osteoporosis and normal bones was studied by high-resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). However, some studies revealed that not only calcium is involved in bone strengthening as risk factor of fracture osteoporosis. Our work is believed to contribute a further insight of precipitate and structural evolution in Galfenol and is significant to maintain the magnetostriction performance of Galfenol in service.Clinical research indicates that negative calcium balance is associated with low bone mass, rapid bone loss, and high fracture rates. Further magnetostrictive measurements reveal the ω phase precipitates deteriorate the magnetostriction of Galfenol as empirically expected. Density functional theory calculations unveil the precipitate of ω phase in Galfenol is theoretically possible. Their orientation relationships with the long range ordered bcc structure of D0 3 can be well indexed into (0003) ω1 ω1 || ( 4 4 ¯ 4 ¯) D03 D03 || ( 4 ¯ 40 1 ¯) ω2 ω2. The ω precipitates with two variants are directly probed to be decomposed from FeGa bcc matrix with the assistances of both spinodal decomposition and displacive transformation. In this work, we firstly report an atomic observation of ω phase transformation in Galfenol under low temperature aging by spherical aberration-corrected transmission electron microscopy. However, the lack of direct probes of phase transformation and intermediate phase related to lattice softening blocks the comprehensive understanding of their intrinsic magnetostrictive mechanism and further improvement of their performance. Galfenol owing excellent deformation due to lattice softening are regarded as a new generation of smart magnetostrictive materials.
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