Dilute Vapor Absorption: A New Accurate Technique for Measurement of the Limiting Activity Coefficient of Water in Hydrophobic Solvents of Lower Volatility
An accurate experimental method for the determination of the limiting activity coefficient of water in hydrophobic solvents was described theoretically; the pertinent apparatus was built and its performance was duly verified. The method is based on continuously saturating the solvent by a gas stream of a constant and known humidity up to the attainment of the steady state and subsequent determination of the water content in the solvent by Karl Fischer titration. Using this new method, accurate values of the limiting activity coefficient of water were determined in eight selected solvents. The measurements were carried out at several temperatures and from these data the infinite dilution dissolution enthalpy and entropy of water in the solvents were evaluated. They both exhibit highly positive values reflecting the breakage of the hydrogen bonding network of water upon its dissolution in the solvents. Prediction of the water limiting activity coefficients was further attempted using the Modified UNIFAC met...
We recently generalized the formerly alignment-dependent multivariate image analysis applied to quantitative structure–activity relationships (MIA-QSAR) method through the application of the discrete Fourier transform (DFT), allowing for its application to noncongruent and structurally dive ... more
Poly-ADP-ribosylation (PARylation) is a protein posttranslational modification (PTM) that is critically involved in many biological processes that are linked to cell stress responses. It is catalyzed by a class of enzymes known as poly-ADP-ribose polymerases (PARPs). In particular, PARP1 is ... more
This review focuses on the type A cytochrome c oxidases (CcO), which are found in all mitochondria and also in several aerobic bacteria. CcO catalyzes the respiratory reduction of dioxygen (O2) to water by an intriguing mechanism, the details of which are fairly well understood today as a r ... more
Rohm and Haas Powder Coatings is delighted to announce that its Reading, Pennsylvania, facility is the first site in the world to receive the RCMS® Site Certification awarded by the American Chemical Council (ACC).
When Raj Gupta, Chairman and CEO of Rohm and Haas Company, became Chairman ... more