Nalco Holding Company

About: Nalco Holding Company is a based out in . It is known for research contribution in the topics: Corrosion & Aqueous solution. The organization has 2375 authors who have published 3056 publications receiving 51473 citations.

Imidazoline corrosion inhibitors

Abstract: This invention provides a series of novel acrylated, substituted imidazoline corrosion inhibitors of the formula (I) wherein R1 is an alkyl radical having from 2 to 8 carbon atoms; R2 is a radical derived from a fatty acid; and R3 is a radical derived from an unsaturated acid and a method for inhibiting corrosion in metallic flow lines through the introduction of such inhibitors into a system wherein corrosion is sought to be precluded.

Carboxylate containing modified acrylamide polymers

Abstract: A high temperature, pressurized process is described to synthesize substituted carboxylated modified acrylamide polymers represented by the structure: ##STR1## wherein X is from the group --SO 3 M, --PO 3 M 2 , --COOR, --OR, ##STR2## and mixtures thereof.

Ambient pH controls glycogen levels by regulating glycogen synthase gene expression in Neurospora crassa. New insights into the pH signaling pathway.

Abstract: Glycogen is a polysaccharide widely distributed in microorganisms and animal cells and its metabolism is under intricate regulation. Its accumulation in a specific situation results from the balance between glycogen synthase and glycogen phosphorylase activities that control synthesis and degradation, respectively. These enzymes are highly regulated at transcriptional and post-translational levels. The existence of a DNA motif for the Aspergillus nidulans pH responsive transcription factor PacC in the promoter of the gene encoding glycogen synthase (gsn) in Neurospora crassa prompted us to investigate whether this transcription factor regulates glycogen accumulation. Transcription factors such as PacC in A. nidulans and Rim101p in Saccharomyces cerevisiae play a role in the signaling pathway that mediates adaptation to ambient pH by inducing the expression of alkaline genes and repressing acidic genes. We showed here that at pH 7.8 pacC was over-expressed and gsn was down-regulated in wild-type N. crassa coinciding with low glycogen accumulation. In the pacCKO strain the glycogen levels and gsn expression at alkaline pH were, respectively, similar to and higher than the wild-type strain at normal pH (5.8). These results characterize gsn as an acidic gene and suggest a regulatory role for PACC in gsn expression. The truncated recombinant protein, containing the DNA-binding domain specifically bound to a gsn DNA fragment containing the PacC motif. DNA-protein complexes were observed with extracts from cells grown at normal and alkaline pH and confirmed by ChIP-PCR analysis. The PACC present in these extracts showed equal molecular mass, indicating that the protein is already processed at normal pH, in contrast to A. nidulans. Together, these results show that the pH signaling pathway controls glycogen accumulation by regulating gsn expression and suggest the existence of a different mechanism for PACC activation in N. crassa.

A subnanoscale study of the nucleation, growth, and coarsening kinetics of Cu-rich precipitates in a multicomponent Fe – Cu based steel

Abstract: The nucleation, growth, and coarsening kinetics of Cu-rich precipitates in a multicomponent Fe – Cu based steel, containing 1.17 at.% Cu, aged at 500 °C for up to 1024 h are investigated. The temporal evolution of the precipitate, heterophase interface, matrix compositions and precipitate morphology are presented. Coarsening temporal exponents are determined for mean radius, number density, and supersaturations, and are compared to the Lifshitz – Slyzov – Wagner model for coarsening, modified for multicomponent alloys by Umantsev and Olson. The experimental results indicate that the alloy does not strictly follow Umantsev – Olson model behavior. Additionally, we compare the results to an investigation of a similar multicomponent steel containing 1.82 at.% Cu and to results in the literature. Furthermore, we present a Thermo-Calc determined phase diagram.