Results 11 to 20 of about 5,947,585 (288)
Chemical analysis and Vickers hardness of orthodontic mini-implants
Brazilian Journal of Oral Sciences, 2015 Orthodontic mini-implants are used in clinical practice to provide efficient and aesthetically-pleasing anchorage. Aim: To evaluate the hardness (Vickers hardness) and chemical composition of miniimplant titanium alloys from five commercial brands ...
Christiane Cavalcante Feitoza +5 more
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Specific Impulse and Absolute Chemical Hardness [PDF]
, 2020 The present work is dedicated to show that there are relationships between the absolute chemical hardness (η) of monopropellants and their specific impulse (I s ). A total of sixteen monopropellants have been modelled and the absolute hardness obtained by quantum chemical calculations.
George Santos Marinho, Robson de Farias
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CHEMICAL AND PHYSICAL HARDNESS OF SOLIDS
MRS Proceedings, 2004 ABSTRACTThe concept of chemical hardness was originally developed as a measure of the stability of molecules. Its relationship to physical hardness and to solids is demonstrated here. Also, it is shown that shear moduli, and polarizabilitites, as well as band gaps are related to chemical hardness.
John J. Gilman
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The Fukui potential is a measure of the chemical hardness [PDF]
Chemical Physics Letters, 2011 Abstract The chemical hardness is, after the chemical potential, the most important concept in describing the chemical reactivity of atoms and molecules. Recently, we showed that the Fukui potential at the nucleus of an atom is proportional to its hardness.
Carlos Cárdenas, Cárdenas, Carlos
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Hardness dynamics in a chemical reaction
Chemical Physics Letters, 1994 Temporal evolution of local and global hardness during a chemical reaction modelled as a collision process between a nitrogen atom and a proton has been studied within a quantum fluid density functional framework. Variation of local hardness is similar to that of charge density.
P.K. Chattaraj, S. Nath
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Koopmans' Analysis of Chemical Hardness with Spectral-Like Resolution [PDF]
The Scientific World Journal, 2013 Three approximation levels of Koopmans' theorem are explored and applied: the first referring to the inner quantum behavior of the orbitalic energies that depart from the genuine ones in Fock space when the wave-functions' Hilbert-Banach basis set is ...
Mihai V. Putz
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Change of Hardness and Chemical Potential in Chemical Binding: A Quantitative Model
The Journal of Physical Chemistry, 1994 In this paper we relate the change of chemical hardness and potential with the binding energies as the chemical binding takes place. We use a simple model to demonstrate that the hardness change is not only related to the binding energy of the molecule being formed, but also to the binding energies of the corresponding molecular cations and anions ...
Sourav Pal, Ramkinkar Roy, A. K. Chandra
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Researches on the chemical composition and hardness modifications that appear in the material of tools used for rubber waste attrition [PDF]
Metalurgija, 2012 This paper presents the results of the main changes in the chemical composition of the material, and changes in its hardness. The changes in terms of chemical composition refer primarily to changes in concentration of sulfur and carbon, and in terms of ...
C. Iancu, D. Dobrotă
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Chemical hardness, linear response, and pseudopotential transferability [PDF]
Physical Review B, 1995 We propose a systematic method of analyzing pseudopotential transferability based on linear-response properties of the free atom, including self-consistent chemical hardness and polarizability. Our calculation of hardness extends the approach of Teter\cite{teter} not only by including self-consistency, but also by generalizing to non-diagonal hardness ...
Filippetti, A. +4 more
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Kaya's composite descriptor and Maximum Composite Hardness Rule for chemical reactions
, 2022 Within the framework of Maximum Hardness and Minimum Polarizability Principles and as compatible with Jenkins Volume Based Thermodynamics approach, Kaya and coworkers calculated the lattice energies of inorganic ionic crystals using their eta(M)/V-m(1/3)
Özbakır Işın, Dilara +3 more
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