We observed the bare W2(+) metal cation upon electron ionization of the weakly bound W(CO)6 dimer. This metal cation can be only observed due to the fast conversion of the weak cluster bond into a strong covalent bond between the metal moieties.

since industrial revolution heavy metals such as lead (pb) and cadmium (cd) have been extensively dispersed in environment which, unknown biological effects and prolong biological half-life make them as a major hazard to human health. in addition, the sharp increase in multiple sclerosis incidence rates has been recorded in iran. the propose of this study was to measuring blood lead and cadmium...

The ability to form multiple carbon-carbon bonds in a controlled sequence and thus rapidly build molecular complexity in an iterative fashion is an important goal in modern chemical synthesis. In recent times, transition-metal-catalysed coupling reactions have dominated in the development of C-C bond forming processes. A desire to reduce the reliance on precious metals and a need to obtain prod...

PURPOSE Pre-surface treatments of coping materials have been recommended to enhance the bonding to the veneering ceramic. Little is known on the effect on shear bond strength, particularly with new coping material. The aim of this study was to investigate the shear bond strength of veneering ceramic to three coping materials: i) metal alloy (MA), ii) zirconia oxide (ZO), and iii) lithium disili...

Transition metal-catalyzed reactions proceed through multiple elementary steps in general and, consequently, the mechanisms are often complicated, especially when backbone structures are reconstructed through a sequence of cleavage and formation of C–C bonds. A step-by-step understanding of elementary steps would be valuable to understand such catalytic transformations. This chapter focuses on ...

Background: The purpose of this study was to compare and evaluate the effects of metal primer on the shear bond strength of denture base resin to base metal alloy after electrolytic and laser etching. Materials and Methods: A total of 48 cobalt‐chromium (Co‐Cr) alloy specimens were fabricated. The specimens were divided into 6 groups of 8 specimens each. Group I: Sandblasting (control group). G...

We present a database of 21 bond dissociation energies for breaking metal-ligand bonds. The molecules in the metal-ligand bond energy database are AgH, CoH, CoO+, CoOH+, CrCH3+, CuOH2+, FeH, Fe(CO)5, FeO, FeS, LiCl, LiO, MgO, MnCH3NiCH2+, Ni(CO)4, RhC, VCO+, VO, and VS. We have also created databases of metal-ligand bond lengths and atomic ionization potentials. The molecules used for bond leng...

PURPOSE The purpose of this study was to compare the fracture strength of the metal and the bond strength in metal-ceramic restorations produced by selective laser sintering (SLS) and by conventional casting (CAST). MATERIALS AND METHODS Non-precious alloy (StarLoy C, DeguDent, Hanau, Germany) was used in CAST group and metal powder (SP2, EOS GmbH, Munich, Germany) in SLS group. Metal specime...