background and aims. various factors influence the interfacial bond between the fiber posts and root canal dentin. the aim of the present study was to evaluate the effect of pre-warming of resin cement on the push-out bond strength of fiber posts to various segments of root canal dentin. materials and methods. in this in vitro study, 40 single-rooted human premolars were decoronated and underwe...

background: the purpose of this study was to compare the push-out bond strength of mineral trioxide aggregate (mta) and calcium enriched mixture (cem) as root end fi lling materials. materials and methods: a total of 40 root dentin slices (1 ± 0.2 mm) were prepared from freshly extracted human maxillary central teeth and their lumens were enlarged to 1.3 mm. the slices were randomly divided int...

In the present study, the presence of brass mesh on the bond strength of aluminum (AA1050) strips in the cold roll bonding process was investigated. The influence of various process parameters including reduction in thickness, pre-rolling annealing, initial thickness of the strips, and post-rolling annealing was also considered. After cold roll bonding process, peeling test was carried out and ...

Electron motion in chemical bonds occurs on an attosecond timescale. This ultrafast motion can be driven by strong laser fields. Ultrashort asymmetric laser pulses are known to direct electrons to a certain direction. But do symmetric laser pulses destroy symmetry in breaking chemical bonds? Here we answer this question in the affirmative by employing a two-particle coincidence technique to inv...

Searching and designing materials with extremely low lattice thermal conductivity (LTC) has attracted considerable attention in material sciences. Here we systematically demonstrate the diverse lattice dynamics of the ternary Cu-Sb-Se compounds due to the different chemical-bond environments. For Cu3SbSe4 and CuSbSe2, the chemical bond strength is nearly equally distributed in crystalline bulk,...

We explore explicit electron pair behaviour within the chemical bond (and lone pairs) by calculating the probability distribution for the center-of-mass (extracule) of an electron pair described by single localized orbitals. Using Edmiston-Ruedenberg localized orbitals in a series of 61 chemical systems, we demonstrate the utility of the extracule density as an interpretive tool in chemistry. B...

From a simplified version of the mathematical structure of the strong coupling limit of the exact exchange-correlation functional, we construct an approximation for the electronic repulsion energy at physical coupling strength, which is fully nonlocal. This functional is self-interaction free and yields energy densities within the definition of the electrostatic potential of the exchange-correl...