In order to examine some possible tyrosyl interactions, poly-tyrosyl lysozyme and poly-O-methyltyrosyl lysozyme were prepared and their solubilities were compared. Both derivatives exhibited
similar pH dependent solubilities, showing a minimum solubility at
about pH 8. Their solubilities varied with temperature, having a
positive enthalpy of solution. The effect of a...
Polypeptidyl derivatives of bovine pancreatic ribonuclease
(RNase) containing two or three tyrosine chains
with an average of two to three residues per chain have
been prepared. The effects of various perturbants such as
neutral salts, ethanol, urea and guanidine hydrochloride
on the thermal transition of the derivatives have been
studied....
An oscillating plasma glow discharge detector for gas
chromatography is used to obtain fingerprint information
about an analyte by combining both the average cell
current and oscillation frequency signals. Five homologs
each of the n-alkanes, 1-alkenes, 1-alkynes, 2-ketones and
aldehydes are studied. Although triplicate determinations
had some scatter due to...
Polybenzimidazoles were synthesized from 3,3'-diaminobenzidine (DAB) and dicarboxylic acids. The polymerizations using the dicarboxylic acid monomers were carried out in polyphosphoric acid (PPA) and phosphorus pentoxide/methansulfonic acid (PPMA) which acted as the solvent and condensing agent. The resulting polybenzimidazoles had inherent viscosities in the range of 0.12 to 0.84 dL/g....
A comparative study was made on the effect of urea denaturation
of bovine serum albumin (BSA), polyglycyl BSA and poly-L-phenylalanyl
BSA. The denaturation process was followed by ultraviolet
spectrophotometry and optical rotation.
A blue shift in the absorption maximum at 278 mμ was observed
in urea denatured proteins, In 7M...
Many pesticides, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers
(PBDEs), and polycyclic aromatic hydrocarbons are persistent, bio-accumulative, and
toxic. These semi-volatile organic compounds (SOCs) can undergo atmospheric
transport and deposition in cold, remote ecosystems. A better understanding of their
accumulation in the fish of these ecosystems is important to better predict...
The objective of this research was to assess the variability of POP deposition by snow on a 10 km spatial scale by measuring the POP concentrations in fresh-fallen snow from remote alpine sites. Samples of pre-metamorphic snow were concurrently collected from three remote alpine sites, of matched altitude and exposure,...