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.

the adsorption of pyrazolone(hpmsp), calix[4]-arene,cu and cs, on carbon nanotube(cnt) atroom temperature has been investigated using spectroscopy.uv spectroscopy indicated that pyrazolone molecules adsorbed on carbon nanotube at roomtemperature in compared calix[4]- arene molecules adsorbed approximately same.the amount ofpyrazolone(hpmsp) adsorb 3.8. le mol/g and amount calix[4]-arene adsorbe...

The cleavage of a DNA phosphodiester bond by Escherichia coli DNA topoisomerase I and the simultaneous covalent linkage of the enzyme to the 5’-phosphoryl group of the DNA at the cleavage site have been reported previously (Depew, R. E., Liu, L. F., and Wang, J. C. (1978) J. Biol. Chem 253, 511-518; Liu, L. F., and Wang, J. C. (1979) J. Biol. Chem 254, 11082-11088). With either E. coli or Micmc...

It is stressed that the two-center exchange energy components lead to a significant lowering of the total molecular energy because of exclusion of self-repulsion, and this is inevitable for covalent bond formation. The success of the two-center bond order index relies on the fact that it gives a qualitative estimate of this important phenomenon.

A recombinant thermostable lipase (Pf2001Δ60) from the hyperthermophilic Archaeon Pyrococcus furiosus (PFUL) was immobilized by hydrophobic interaction on octyl-agarose (octyl PFUL) and by covalent bond on aldehyde activated-agarose in the presence of DTT at pH = 7.0 (one-point covalent attachment) (glyoxyl-DTT PFUL) and on glyoxyl-agarose at pH 10.2 (multipoint covalent attachment) (glyoxyl PF...

The first-principles density functional molecular dynamics simulations have been carried out to investigate the geometric, the electronic, and the finite temperature properties of pure Li clusters Li10, Li12 and Al-doped Li clusters Li10Al, Li10Al2 . We find that the addition of two Al impurities in Li10 results in a substantial structural change, while the addition of one Al impurity causes a ...

Peptides are short chains of amino acid monomer molecules linked through a covalent chemical bond (Scitable). They are designed to start, promote, and prohibit several cellular functions through chemical secretion—from paracrine and endocrine signals to various growth factors and neurotransmitters. Operating at the cellular level, peptides secrete elements that promote and regulate a wide varie...