ABSTRACT
An absorption spectrometer equipped with a IV-VI semiconductor tunable mid-IR diode laser was used to make sensitive measurements of benzene (C(6)H(6)) gas in the 5.1-microm spectral range. Wavelength modulation coupled with second-harmonic detection achieved accurate real-time quantification of benzene concentrations down to a minimum detection limit of 1 ppmv with an integration time of 4 s. A variety of calibrated benzene-sensing measurements were made, including the determination of the benzene concentrations in vehicle exhaust and headspace vapors from unleaded gasoline and other liquids. Kinetic phenomena, including the monitoring of benzene evaporation and absorption/desorption by granulated activated carbon were observed with the instrument. Measurements were performed that allowed experimental determination of the activation energy for desorption of benzene from activated carbon, which was found to be 198 meV/molecule (19.0 kJ/mol).
ABSTRACT
The reported high level of depression and suicide among 59 Ethiopian single male refugees is often related to their being culturally and ethnically distinct in the US. Research investigating the psychological well-being of these refugees in California, Washington, and Nevada indicates that the level of stress among Ethiopian refugees resettled by agencies is higher than the stress of those resettled by volunteers. When English facility is held constant, the differential ability of these 2 resettlement methodologies to provide appropriate employment and access to higher education varies directly with the stress levels. Recommendations for improvement of resettlement are offered.
