New Method of Simulation to Evaluate the Sensitivity to Oxidation of Lubricating Oils: An Aging Cell Coupled with Fourier Transform Infrared Spectroscopy

Abstract

This study presents a new method for evaluating the oxidation of lubricating oils. An aging cell adapted to a Fourier transform infrared (FT-IR) spectrometer allows the continuous and direct study of the oxidative aging of base oils. During the test, oxidation bands appeared in the spectra (carbonyl bands around 1730 cm(-1)). The graphic representation of the carbonyl band modification--using a spectroscopic index--makes it possible to monitor the evolution of the lubricant composition. Comparing the oxidation constants, determined from the kinetic plots of several base oils, makes it possible to evaluate their relative sensitivity.

Preliminary studies on the mid-infrared analysis of edible oils by direct heating on an ATR diamond crystal

“…Most of the curves for olive and especially sunflower oil observed in Fig. 2a have three phases, as already described by Priéri, Gresser, Le Dréau, Obiols, and Kister (2008).…”

Cellular senescence and the aging brain

“…Thus far, replication-competent cell types that undergo senescence include fibroblasts, epithelial cells, melanocytes, endothelial cells, astrocytes and many others (Bitto et al, 2010; Coppe et al, 2010; Coppe et al, 2008; Voghel et al, 2007; Wajapeyee et al, 2008). The senescence response arrests cell proliferation, stably and essentially irreversibly, in response to stresses that puts cells at risk for malignant transformation (Campisi, 2001; Collado and Serrano, 2010; Prieri et al, 2008). These stresses include repeated cell division that erodes telomeres (perceived by cells as severely damaged DNA), DNA damage anywhere in the genome, and disrupted chromatin (epigenomic damage) (Campisi, 2007; Guney et al, 2006; Rodier et al, 2005; Shay and Wright, 2005).…”

Reactivity of Triphenyl Phosphorothionate in Lubricant Oil Solution

“…FT-IR and NMR spectroscopy have already been used to identify the oxidation products and to investigate the oxidation kinetics [46,[49][50][51][52][53][54]. The appearance of two broad absorption bands in the 1850-1685 cm -1 and in the 1300-850 cm -1 regions of the FT-IR spectrum, corresponding, respectively, to the stretching vibration of the C=O and C-O bonds, has been used to follow the oil-aging process [46,50,53].…”

“…The appearance of two broad absorption bands in the 1850-1685 cm -1 and in the 1300-850 cm -1 regions of the FT-IR spectrum, corresponding, respectively, to the stretching vibration of the C=O and C-O bonds, has been used to follow the oil-aging process [46,50,53]. However, the complex carbonyl envelope made it difficult to give a definitive statement on the chemical nature and distribution of all the species involved [46,50].…”