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Vibrational energy levels of an anharmonic oscillator representative of longitudinal oscillations of atoms in a crystal lattice, showing finite vibrations in the ground state existent at absolute zero. The vibrational energy, En, is given as a function of the vibrational quantum number, n, the Planck constant, h, and the vibration frequency, ν.

Vibrational energy levels of an anharmonic oscillator representative of longitudinal oscillations of atoms in a crystal lattice, showing finite vibrations in the ground state existent at absolute zero. The vibrational energy, En, is given as a function of the vibrational quantum number, n, the Planck constant, h, and the vibration frequency, ν.

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Every time we communicate our science, we are involuntarily involved in an educational activity, affecting the listeners' methodology and motivation. In a beautiful metaphor, late Nobel Laureate, Richard E. Smalley compared interacting atoms and molecules to boys and girls falling in love. Elaborated and exemplified with a couple of entertaining an...

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... crystal lattice vibrations exist even at absolute zero. Fig.6 illustrates this effect, which could be also described by saying that all is music, music that never stops. ...

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Nous analysons dans l’étude des séismes, au cycle 3 de l’école primaire, le moment de l’introduction de l’instrument sismographe. Les deux professeurs enquêtés accompagnent cette introduction de gestes à valeur explicative. Par cette ostension, ces professeurs présentent le fonctionnement général d’un instrument lointain, un sismographe mécanique,...

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... Their basal planes displayed the characteristic hexagonal features, being an indirect evidence of their growth along the crystallographic c-axis, which is normally most favorable for HAp [43,44]. The central tips topping these basal hexagons are explained by the fact that the fastest growing faces on a crystal are also those disappearing from its surface the fastest [45], in this case leaving the prominent {111} faces in lieu of the (001) one. These morphological differences combined indicate that germanate ions affected the nucleation and crystal growth remarkably and rather desirably from the perspective of controlled fine particle synthesis. ...
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Hydroxyapatite (HAp) is the major component of all boney tissues in mammals. Because of this omnipresence in the living world, HAp possesses an exceptional biocompatibility. The downside of this omnipresence, however, comes in the form of its mild to moderate biological activities. One means of augmenting these activities involves the doping of HAp with foreign ions. Here, the first synthesis and characterization of HAp doped with germanium ions is being reported. Germanium was deliberately integrated into the crystal lattice of HAp in the form of germanate anions. Approximately two thirds of the germanate ions introduced into the hydrothermal solution got incorporated into the HAp lattice, yielding the approximate stoichiometry of Ca 10-x (PO 4) 5.62+y (GeO 3) 0.38 (OH) 2-z. Germanates replaced the phosphates of stoichiometric HAp and induced the expansion of the HAp lattice both along the screw axis of the calcium ion hexagons and in the direction parallel to the basal plane. Simultaneously, the larger size and the triple valency of the germanate ion as compared to the smaller and trivalent phosphates prompted the bond distortion and charge compensation through defect formation , which reduced the crystallinity and increased the microstrain of the HAp lattice. Vibrational spectro-scopic analyses corroborated these crystallographic effects by demonstrating the enhanced heterogeneity of the environments surrounding the active modes after germanate ions were incorporated into HAp. Conforming to La Châtelier's principle, this reduction of the crystallographic order increased the capacity of the material for integration of adventitious carbonates. However, the inclusion of germanate ions induced a partial shift of these carbonates to the hydroxyl channel sites, thus decreasing the ratio of the B-type carbonation to the A-type carbonation. Introduced into HAp, germanium acted as a superb regulator of the particle size and morphology, enhancing their fineness and uniformity. Inclusion of germanate ions also increased the electrophoretic mobility and hydrodynamic surface charge density of the particles by reducing their size and by inducing a more sto-chastic distribution of terminal ionic groups due to the bending of the crystal facets. Overall, the doping of HAp with germanate ions facilitated the production of narrowly dispersed nanorods with a moderately enhanced structural disorder and with a pronounced potential for the biomedical niche.
... Humans, after all, are social creatures and although social interaction is not necessary for learning to occur, it is essential for creating communicable skills, from which both humanity and the organisms attaining them will benefit. Values distilled through such interaction inconspicuously guide the creative efforts in science, whose extraordinary accomplishments have often fed on the insights from arts and humanities, let alone daily experiences and inspiration found therein (Uskoković 2014). Although the effects of such values are extraordinarily difficult to trace, the absence of evidence should not be confused here with the evidence of absence and their presence and effect on scientific creativity ought to be acknowledged as immanent, albeit subtle and elusive. ...
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Scientific articles have been traditionally written from single points of view. In contrast, new knowledge is derived strictly from a dialectical process, through interbreeding of partially disparate perspectives. Dialogues, therefore, present a more veritable form for representing the process behind knowledge creation. They are also less prone to dogmatically disseminate ideas than monologues, alongside raising awareness of the necessity for discussion and challenging of differing points of view, through which knowledge evolves. Here we celebrate 250 years since the discovery of the chemical identity of the inorganic component of bone in 1769 by Johan Gottlieb Gahn through one such imaginary dialogue between two seasoned researchers and aficionados of this material. We provide the statistics on ups and downs in the popularity of this material throughout the history and also discuss important achievements and challenges associated with it. The shadow of Samuel Beckett’s Waiting for Godot is cast over the dialogue, acting as its frequent reference point and the guide. With this dialogue presented in the format of a play, we provide hope that conversational or dramaturgical compositions of scientific articles—albeit virtually prohibited from the scientific literature of the day—may become more pervasive in the future.
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