Spectroscopic Methods For Lubricant Quality Control In Engines And Gear Boxes

Lubricants play a vital role in reducing the wear and tear of engine/gear box metal parts. Number of analytical and spectroscopic methods have been used to analyze the quality of the lubricant oil. Moreover some parameters such as Total Acid Number (TAN), viscosity index also have been used to analyze the quality of the oil. Several used wind turbine gear oil samples were analyzed by various spectroscopic methods such as UV-Visible, Fourier-transform infrared (FTIR) and Fluorescence Spectroscopy. Fluorescence method gave promising results among those three spectroscopic methods. In order to study thermal degradation, motor oil samples were subjected to artificial aging in the laboratory conditions by heating them up to different temperatures for different time periods and then subsequently analyzed with fluorescence spectroscopic method. Subsequently two used engine oil samples from a same diesel engine vehicle were analyzed using fluorescence spectroscopic method.  Notable variation in fluorescence emission intensities was observed with oil aging. Intensity of the fluorescence emission signal decrease with oil degradation.  Therefore fluorescence spectroscopic method can be used to predict the reusability of gear oils as well as to identify the oil degradation. This method can be further extended to develop a novel potential sensor to detect the quality of oil in various types of engines. KEYWORDS: Lubricant oil, Oil degradation, Fluorescence spectroscopy, Analytical methods

Quantitative characterization of individual microdroplets using surface-enhanced resonance Raman scattering spectroscopy

Surface-enhanced resonance Raman scattering (SERRS) spectroscopy is a highly sensitive optical technique capable of detecting multiple analytes rapidly and simultaneously. There is significant interest in SERRS detection in micro- and nanotechnologies, as it can be used to detect extremely low analyte concentrations in small volumes of fluids, particularly in microfluidic systems. There is also rapidly growing interest in the field of microdroplets, which promises to offer the analyst many potential advantages over existing technologies for both design and control of microfluidic assays. While there have been rapid advances in both fields in recent years, the literature on SERRS-based detection of individual microdroplets remains lacking. In this paper, we demonstrate the ability to quantitatively detect multiple variable analyte concentrations from within individual microdroplets in real time using SERRS spectroscopy. We also demonstrate the use of a programmable pump control algorithm to generate concentration gradients across a chain of droplets