Laser-induced breakdown spectroscopy (LIBS): a new spectrochemical technique

We have used the breakdown spark from a focused laser beam to generate analytically useful emission spectra of minor constituents in air and other carrier gases. The medium was sampled directly. It was not necessary to reduce the sample to solution nor to introduce electrodes. The apparatus is particularly simple; a pulsed laser, spectrometer, and some method for time resolution. The latter is essential in laser-induced-breakdown spectroscopy (LIBS) because of the strong early continuum. High temperatures in the spark result in vaporization of small particles, dissociation of molecules, and excitation of atomic and ionic spectra, including species which are normally difficult to detect. In one application, we have monitored beryllium in air at conventrations below 1 ..mu..g/m/sup 3/, which is below 1 ppB (w/w). In another we have monitored chlorine and fluorine atoms in real time. LIBS has the potential for real-time direct sampling of contaminants in situ

Policy and Non-Policy Determinants of U.S. Equity Foreign Direct Investment

This study examined the effects of policy and non-policy variables on the location of new U.S. direct investment abroad (as distinct from reinvested earnings of existing affiliates), using 1977 and 1982 Benchmark data. The data revealed statistically significant effects for investment incentives (positive), performance requirements (negative), and host country effective tax rates (negative) with interesting differences between the two time periods and between developed versus developing countries. Significance was also found for non-policy variables such as political stability, cultural distance, GDP per capita, and infrastructure.© 1995 JIBS. Journal of International Business Studies (1995) 26, 281–299

International acquisitions: do financial analysts take note?

Recent research has determined that managers are increasingly concerned with how institutional investors and securities analysts view their companies' long term strategies. This article examines characteristics of international acquisitions that influence professional stock analysts' estimates of the acquirer's earnings per share. Previous international acquisition experience and target country operating experience positively affect analysts' estimates of stock earnings, and relatedness between the parent and target business lines also affects analyst estimates when viewed in light of operating experience in the acquisition target's home country.

Real-time monitoring of airborne beryllium, at OSHA limit levels, by time-resolved laser-induced breakdown spectroscopy

Real-time detection of beryllium particulate is being investigated by the new technique of laser-induced breakdown spectroscopy. For beryllium detection we monitor the 313.1-nm feature of once ionized beryllium (Be II). Numerous publications describe the technique, our beryllium results, and other applications. Here we summarize the important points and describe our experiments with beryllium

Optical instrumentation for on-line analysis of chemical processes

Optical diagnostics provide the capability for nonintrusive, on-line, real time analysis of chemical process streams. Several laser-based methods for monitoring fossil energy processes have been evaluated. Among the instrumentation techniques which appear quite promising are coherent anti-Stokes Raman spectroscopy (CARS), laser-induced breakdown spectroscopy (LIBS), and synchronous detection of laser-induced fluorescence (SDLIF). A CARS diagnostic was implemented on a coal gasifier and was successfully employed to measure species concentrations and temperatures within the process stream. The LIBS approach has been used to identify total trace impurities (e.g., Na, K, and S) within a gasifier. Recently, individual components in mixtures of aromatics hydrocarbons have been resolved via the synchronous detection of laser-induced fluorescence. 9 figures