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A challenging aspect of local loading is that a restricted volume of structure contributes in tolerating external loading and therefore most of the remote zones of the structure remain intact. The present study surveys the effect of using incompressible fluid as a continuum to transfer the impact energy to a broader volume of the structure by employing experimental and numerical approaches. For the experimental study, three classes of doubly layered cylinders with different distances between the layers are fabricated from DIN S235JR steel and pure fresh water is used for filling the space between the layers. Instrumented impactors with different masses and falling heights imparted local dynamic energy on the specimens. The experimental results revealed that by the introduction of the fluid, on average, 25 percent of reduction in local deformation could be observed. Moreover, by implementing a validated numerical procedure, the energy contribution of every layer is scrutinized. It is observed that at a special distance between the layer, fluid contribution in impact energy absorption is maximized. Numerical outcomes illustrated a few percent of improvement in terms of energy contribution in inner and outer shells. Also, the probability of instability of the inner shell has been reported. • 25% reduction in local damage severity induced by lateral impact loading. • Enhancing the energy balance of different parts due to effect of the fluid presence. • At a distance between the layers, intensity of fluid absorbed energy is maximized. • Assessment of the fluid, inner and outer shell's contribution in energy absorption. • Comments on symmetric and asymmetric buckling of the inner shell. [ABSTRACT FROM AUTHOR]

Abstract: Periodic slab calculations in generalized gradient approximation density–functional theory (GGA–DFT) have been used to demonstrate how the existence of second metals can modify the atomic oxygen adsorption on Au (100) surfaces. The computed adsorption energies for atomic oxygen adsorbed at 0.125ML (monolayer) surface coverage on the Au (100) and bimetallic Au–Pt (100), Au–Cu (100), Au–Pt–Au (100) and Au–Cu–Au (100) surfaces are 275.60, 417.96, 427.79, 283.38, and 275.55kJ/mol, respectively. In all coverages, the adsorption energies for Au–Pt and Au–Cu surfaces are higher than that for Au–Pt–Au, Au and Au–Cu–Au. In low coverage (θ <0.5), the adsorption energy for Au–Cu is larger than that for Au–Pt. As the coverage rises, reduces and for Au–Cu becomes smaller than that for Au–Pt. In Au–Cu–Au (100) surface, the largest shift in the d-band center away from the Fermi level results in the weakest oxygen binding energy. [Copyright &y& Elsevier]

Abstract: The intramolecular hydrogen bonding in different conformers of dihydroxyacetone (DHA) and its isomer, glyceraldehyde (Gald) was investigated using Density Functional Theory (DFT), second-order Møller–Plesset (MP2) method and “Atoms in Molecules” (AIM) theory. The effect of intramolecular hydrogen bonding on the relative stability of conformers was studied. It was found that the stability of different conformers depends on the size of the ring in which hydrogen bond is formed and the hybridization of the oxygen atom of acceptor. The AIM analysis showed that some of the considered interactions are not real hydrogen bonds and therefore, there is no cooperativity in the considered conformers. [Copyright &y& Elsevier]

Abstract: The aniline–HCl–A complexes are studied using DFT (B3LYP) method and 6-31+G (d,p) basis set. A is a catalyst molecule such as H2SO4, H2SO3, HCOOH, HNO3, HF, CH3OH, H2O, H2O2, HNO2(b), HNO2(a), NH3, HCOH, HCN, HCl, H2S and PH3. We found that the proton transfer take place in 12 structures in which A=H2SO4, H2SO3, HCOOH, HF, HNO2(a), HNO3, H2O2, H2O, NH3, HNO2(b), HCl, CH3OH and not occurred in another 4 structures with A=HCOH, HCN, H2S and PH3. The interaction energies (E int) of the complexes are computed and correlation between E int and the extent of proton transfer is investigated. The atoms in molecules theory (AIM) of Bader is also applied to study the intra-cluster hydrogen bonds in the aniline–HCl–A clusters. Additionally, the influence of phenyl ring on the proton transfer reaction is computed with the complexes structures without the phenyl ring (NH3–HCl–catalyst). [Copyright &y& Elsevier]