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115 - Jozsef Garai 2014
It is suggested that the substitutional nitrogen in diamonds bonded to three of the surrounding carbon atoms instead of four. This proposed electron configuration of the defect is deduced from previous experiments and theoretical considerations. Nota bly, the 1344 cm-1 band, characteristics of the substitutional Nitrogen, is independent of the isotopic change of Nitrogen but depend on the isotopic change of Carbon. The well established NV centre should not be stable if Nitrogen is bounded to four of the surrounding Carbon. Additional support comes from the substantially bigger size of the single substitutional nitrogen atom indicating loan pair electron. The proposed configuration of the substitutional Nitrogen was also tested by using a simple force constant model. Replacing force constant of C-N with 2/3 C-C:1/3 C=C reproduces the 1344 cm-1 band.
75 - Jozsef Garai 2011
The fundamental organizing principle resulting in the periodic table is the nuclear charge. Arranging the chemical elements in an increasing atomic number order, a symmetry pattern known as the Periodic Table is detectable. The correlation between nu clear charge and the Periodic System of the Chemical Elements (PSCE) indicates that the symmetry emerges from the nucleus. Nuclear symmetry can only exist if the relative positions of the nucleons in the nucleus are invariant. Pauli exclusion principle can also be interpreted as the nucleons should occupy a lattice position. Based on symmetry and other indicatives face centered cubic arrangement have been proposed for the nuclear lattice. A lattice model, representing the protons and the neutrons by equal spheres and arranging them alternately in a face centered cubic structure forming a double tetrahedron, is able to reproduce all of the properties of the nucleus including the quantum numbers and the periodicity of the elements. Based on the geometry of the nuclear structure it is shown that when a new layer of the nuclear structure starts then the distance between the first proton in the new layer and the charge center of the nucleus is smaller than the distance of the proton, which completed the preceding layer. Thus a new valence electron shell should start to develop when the nuclear structure is expanded. The expansion of the double tetrahedron FCC nuclear lattice model offers a feasible physical explanation how the nucleus affects the electronic configuration of the chemical elements depicted by the periodic table.
33 - Jozsef Garai 2010
None of the well established Nitrogen related IR absorption bands, common in synthetic and terrestrial diamonds, have been identified in the pre-solar diamond spectra. In the carbonado diamond spectra only the single nitrogen impurity (C centre) is i dentified and the assignments of the rest of the nitrogen-related bands are still debated. It is speculated that the unidentified bands in the Nitrogen absorption region are not induced by Nitrogen but rather by Nitrogen-hydrides because in the interstellar environment Nitrogen reacts with Hydrogen and forms NH+; NH; NH2; NH3. Among these Hydrides the electronic configuration of NH+ is the closest to Carbon. Thus this ionized Nitrogen-mono-hydride is the best candidate to substitute Carbon in the diamond structure. The bands of the substitutional NH+ defect are deduced by red shifting the irradiation induced N+ bands due to the mass of the additional Hydrogen. The six bands of the NH+ defects are identified in both the pre-solar and the carbonado diamond spectra. The new assignments identify all of the nitrogen-related bands in the spectra, indicating that pre-solar and carbonado diamonds contain only single nitrogen impurities.
262 - Jozsef Garai 2010
Historically, the thermodynamic behavior of gasses was described first and the derived equations were adapted to solids. It is suggested that the current thermodynamic description of solid phase is still incomplete because the isothermal work done on or by the system is not counted in the internal energy. It is also suggested that the isobaric work should not be deducted from the internal energy because the system does not do work when it expands. Further more it is suggested that Joule postulate regarding the mechanical equivalency of heat -the first law of thermodynamics- is not universal and not applicable to elastic solids. The equations for the proposed thermodynamic description of solids are derived and tested by calculating the internal energies of the system using the equation of state of MgO. The agreement with theory is good.
34 - Jozsef Garai 2010
The average distance of the equal hard spheres is introduced to evaluate the density of a given arrangement. The absolute smallest value is two radii because the spheres can not be closer to each other than their diameter. The absolute densest arrang ement of two, three and four spheres is defined, which gives the absolute highest density in one, two and three dimensions. The absolute highest density of equal spheres in three dimensions is the tetrahedron formed by the centers of four spheres touching each other with density of 0.7796. The density of this tetrahedron unit can be maintained only locally because the tetrahedron units can not be expanded to form a tightly packed arrangement in three dimensions. The maximum number of tetrahedron units that one sphere is able to accommodate is twenty which corresponds to the density of 0.684. The only compatible formation of equal spheres which can be mixed with tetrahedron is octahedron. In order to mix the tetrahedron and octahedron units certain geometrical constrains must be satisfied. It is shown that the only possible mixture of tetrahedrons and octahedrons units is the one which accommodates eight tetrahedron and six octahedron vertexes which is identical to FCC and an alternative proof for the Kepler conjecture. It is suggested that there is a density gap between the FCC density and the highest density of disordered arrangements and that the icosahedrons configuration with its 0.684 density represents the upper bound on the disordered arrangements.
42 - Jozsef Garai 2009
Self-resonance in the atomic vibration occurs when the average wavelength of the phonon thermal vibration is equivalent or harmonic of the diameters of the atoms. It is suggested that applying pressure at temperature corresponding to the self-resonan ce should effectively reduce the number of vacancies. This theoretical prediction is tested on Niobium by measuring the magnetic susceptibility of the untreated and treated samples. The applied pressure-temperature treatment increased the critical temperature of Niobium by about 30 percent which was also accompanied with volume increase.
Collecting the complete data set of previous experiments on periclase, covering a pressure and temperature range of 0-141.8 GPa and 100-3031 K respectively, the first comprehensive P-V-T description of MgO is presented comprising all previous experim ents. The P-V-T EoS of Birch-Murnaghan, Rydberg-Vinet and Garai are determined by unrestricted fitting. The three EoSs are consistent and a unique set of parameters is able to cover the entire pressure and temperature range. The RMS misfits for the pressure are 0.371 GPa, 0.381 GPa and 0.396 GPa for the Garai, Birch-Murnaghan and Rydberg-Vinet EoSs. The RMS misfits for the volume and the temperature are 0.018 cm3 and 60.3 K for the EoS of Garai.
58 - Jozsef Garai 2009
Five new correlations between sunspot activity and orbiting position of the Jovian planets are detected. In order to explain these correlations it is suggested that the resonance of the outer planets destabilizes the orbit of Kuiper Belt Objects and generates a cyclical impact frequency on the Sun. The vaporization of the object initiates a shock way disrupting the upwelling of the plasma resulting in a sunspot formation. The proposed model is able to explain the length of the cycle, the latitude distribution of the sunspots and the extremely long term stability of the cycles. Calculating the positions of the Jovian planets at conjunction and opposition allows the long term prediction of the solar activity.
Pressure-melting temperature relationship is proposed and tested against the experiments of metals (Pt and Al), salt (NaCl), and ceramic (MgO) with positive results. The equation contains one open parameter which remains constant for the investigated substances. The constant value of the parameter indicates that the presented equation for the melting curve might be the first one which does not contain any arbitrary constant which is left open to fit to the experiments.
52 - Jozsef Garai 2009
New model describing the pressure effect on the melting temperature is proposed by using four assumptions. One, the average wavelength of the phonon vibration at the Debye temperature corresponds to the length of the unit cell. Two, the phonon vibrat ion at the melting temperature is in self-resonance with the lattice vibration of the surface atomic/molecular layer. Three, the phonon wavelength ratio of the Debye and the melting temperature does not be affected by the pressure. Four the pressure reduces the anharmonic part of the vibration. The relevant equations are derived and tested against the experiments of sodium with positive result.
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