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Optical hyperfinestructure investigations in several spectral lines were carried out in the Sb-I spectrum from which for the first time accurate values of the hfs-splitting constants A and B of the ground configuration 5p 3 and also for five of the eight levels of the first excited configuration 5p 2 6s were obtained. With these parameters the influence of core polarization effects is calculated to be a c = -6.6(4)mK, (equivalent to a magnetic field of -283 (20) (10) inK, and a value 6(r2) 121' 123 =0.12(4) fm 2 for the change in the mean square nuclear charge radius between 121Sb and ~ 23Sb which is about 50 percent of the prediction of the unified nuclear model.

The aim of this study was to develop further surface‐enhanced Raman scattering (SERS) substrates appropriate for the in situ environmental determination of chemicals in sea‐water important for global environmental problems. By encapsulating silver colloids in a sol–gel‐derived xerogel, SERS‐active coatings were produced with the high mechanical and chemical stability required for underwater field measurements. A flow‐through system was used which simulates measurements under real flow conditions. Substrates were optimized regarding sensitivity to different analytes and long‐term stability by varying solvent type, pH and sol–gel precursors. The substrates were characterized by their SERS activity and calibration functions of the Langmuir isotherm type were found for a variety of aromatic hydrocarbons. Limits of detection as low as 9 ppb for phenylacetylene and 135 ppb for biphenyl were achieved. Detailed tests on long‐term stability in sea‐water yielded a substrate half‐life of 13 days, which resulted in a substrate lifetime of at least 5 weeks. Copyright © 2000 John Wiley & Sons, Ltd.

As a tool for the in situ characterization of meat quality, a hand-held Raman sensor head using an excitation wavelength of 671 nm was developed. A microsystem-based external cavity diode laser module was integrated into the sensor head and attached to a Raman probe, which is equipped with lens optics for excitation and signal collection as well as a Raman filter stage for Rayleigh rejection. The Raman signal was guided by an optical fiber to the detection unit, which was in the initial phase a laboratory spectrometer with a charge-coupled device (CCD) detector. The laser and the sensor head were characterized in terms of stability and performance for in situ Raman investigations. Raman spectra of meat were obtained with 35 mW within 5 seconds or less, ensuring short measuring times for the hand-held device. In a series of measurements with raw and packaged pork meat, the Raman sensor head was shown to detect microbial spoilage on the meat surface, even through the packaging foil.