the potential function of lippincott and schroeder for linear hydrogen bond has been re-examined and extended to nonlinear hydrogen bond. the parameters originally introduced to the potential function by lippincott and schroeder have been determined from the structural parameters such as 0.. .odistance 0-h bond distance, h.. .o distance and hoo angle. thevalidity of harmonic oscillator approxim...

The dynamics of water are dramatically modified upon confinement in nanoscale hydrophilic silica pores. In particular, the OH reorientation dynamics of the interfacial water are non-exponential and dramatically slowed relative to the bulk liquid. A detailed analysis of molecular dynamics simulations is carried out to elucidate the microscopic origins of this behavior. The results are analyzed i...

The potential function of Lippincott and Schroeder for linear hydrogen bond has been re-examined and extended to nonlinear hydrogen bond. The parameters originally introduced to the potential function by Lippincott and Schroeder have been determined from the structural parameters such as 0.. .Odistance 0-H bond distance, H.. .O distance and HOO angle. Thevalidity of harmonic oscillator appr...

human serum albumin (hsa) is the most abundant protein constituent of blood plasma. this protein consists of a single polypeptide chain of 585 amino acid residues, which has many important physiological functions. hsa can bind and carry many drugs, including anticoagulants, tranquilizers, and general anesthetics. some technique such as: fluorescence spectroscopy, three-dimensional fluorescence ...

Molecular structure, isomerism, conformational stability and intramolecular hydrogen bonding (IHB) of cis-enol forms of 1-(n-pyridyl)butane-1,3-diones (nPBD) (n = 2, 3, or 4) have been investigated by means of density functional theory (DFT) calculations. Energy differences for all possible nPBD cis-enol forms of isomers with respect to the most stable form of the correspondin...

background and aims. studies have shown decreased bond strength of composite resin to human and bovine bleached enamel. this study evaluated the effect of sodium ascorbate and delayed bonding on the bond strength of two adhesive systems to bleached enamel. materials and methods. the labial surfaces of 150 sound bovine incisor teeth were abraded with abrasive paper. the teeth were randomly divid...

molecular structure, isomerism, conformational stability and intramolecular hydrogen bonding (ihb) of cis-enol forms of 1-(n-pyridyl)butane-1,3-diones (npbd) (n = 2, 3, or 4) have been investigated by means of density functional theory (dft) calculations. energy differences for all possible npbd cis-enol forms of isomers with respect to the most stable form of the corresponding isomer have been...

Tertiary interactions that allow RNA to fold into intricate three-dimensional structures are being identified, but little is known about the thermodynamics of individual interactions. Here we quantify the tertiary structure contributions of individual hydrogen bonds in a "ribose zipper" motif of the recently crystallized Tetrahymena group I intron P4-P6 domain. The 2'-hydroxyls of P4-P6 nucleot...

abstract statement of problem: bleaching systems with different concentrations and applications are widely used to improve the visual appearance of the teeth, but one of the complications of these materials is reduction of bond strength for immediately bonding to the bleached enamel. objectives: the aim of this study was to evaluate the influence of using different modified hydrogen peroxide bl...

the solvatochromism of fluoresceine and its derivatives was studied in solvents of different hydrogen bond donor (hbd), hydrogen bond acceptor (hba), donor number (dn) and acceptor number (an) by their uv-vis spectra. results showed that position, intensity and shape of absorption bands change with type of solvent. these changes can be rationalized by solvatochromic parameters such as α, β, et ...