| Recent improvements in Raman instrumentation have made this technique an attractive alternative to other spectroscopic methods for quantitative analysis. The implementation of highly efficient charge-coupled device (CCD) detectors, holographic filters, fast spectrographs, and fiber optic interfaces, have made Raman spectrometers stable and sensitive enough to make quantitative applications possible. The fiber-optic sampling for Raman spectroscopy greatly simplifies spectral acquisition and makes possible the analysis of hazardous samples and/or samples situated remotely from the laser and spectrograph.; Utilization of chemometrics or multivariate analysis to model complex Raman data allow concentration predictions which can be used for quality control and real-time monitoring of changes in samples with little or no sample preparation.; In Chapter 2, an experimental study of a silicon etch process using etch solutions containing a mixture of CrO{dollar}sb3{dollar}-HF is discussed. These etching solutions are very corrosive and monitoring the etch process demands the use of safe sample handling. In this chapter it is shown that fiber optic Raman spectroscopy can be used as a useful etch bath sensor to measure etch bath conditions, or monitor the etch process in real time.; Nitrate anion exchange is a very important separation process in nuclear fuel reprocessing systems. The parameters that must be controlled for optimum separations are the concentrations of the individual chemical species present in the metal-nitrate solutions. Chapter 3 discusses the analysis of nitrate species in aqueous solutions mimicking those used in the nuclear fuel reprocessing industry. The first part of this chapter is related to the analysis of "free" nitrate in nitric acid containing solutions. The second part of the chapter is a study of the thorium-nitrate system. By applying factor analysis to the spectra of aqueous Th(NO{dollar}sb3)sb4{dollar} solutions, the amount of nitrate bound to thorium and the formation constant for the thorium-nitrate complex has been determined.; The pharmaceutical industry is faced with the task of analyzing a wide variety of solid samples including bulk active ingredients, excipients, formulations and products in the form of capsules or tablets. Raman spectroscopy is becoming an increasingly important technique in the pharmaceutical industry because it provides unique information that complements data generated by other analytical techniques. The main advantage of Raman spectroscopy is the capability of performing rapid, reliable and nondestructive analysis of drug formulations. Experimental results pertaining to the analysis of bucindolol in gel capsules are presented in Chapters 4 and 5. These results suggest it may be feasible to consider an on-line implementation of the Raman technique for real-time analysis of intact drug formulations. (Abstract shortened by UMI.)... |
