The viability of using pulsed laser excited Raman spectroscopy as a method for diamond detection from ore, has been investigated. In this method the spontaneous Stokes Raman signal is used as indicator of diamond, and a dual channel system is necessary for correcting for fluorescence of minerals and diamond itself. Various pulsed laser wavelengths from 266 to 1064nm were used, as well as cw lasers for comparison. Wavelength scans of the regions of interest, indicated that pulsed lasers at 532, 355 and 308nm may be used with confidence for this purpose. Mineral fluorescence did not appear to pose a threat to the method, but rather own fluorescence of some types of diamonds. In this respect, pulsed lasers offer a decided advantage above cw, due to nonlinear increase of fluorescence with laser power, resulting in superior Raman to fluorescence signal ratios. An apparatus constructed for discriminating diamond from ore was evaluated, and using minerals commonly occurring in diamond carrying ore as well as a wide variety of diamonds, it proved to function effectively. A significant improvement in the capability for diamond detection was found when pulsed lasers at 532 and 308nm were used, in comparison to the 532nm cw laser.

The viability of using pulsed laser excited Raman spectroscopy as a method for diamond detection from ore, has been investigated. In this method the spontaneous Stokes Raman signal is used as indicator of diamond, and a dual channel system is necessary for correcting for fluorescence of minerals and diamond itself. Various pulsed laser wavelengths from 266 to 1064nm were used, as well as cw lasers for comparison. Wavelength scans of the regions of interest, indicated that pulsed lasers at 532, 355 and 308nm may be used with confidence for this purpose. Mineral fluorescence did not appear to pose a threat to the method, but rather own fluorescence of some types of diamonds. In this respect, pulsed lasers offer a decided advantage above cw, due to nonlinear increase of fluorescence with laser power, resulting in superior Raman to fluorescence signal ratios. An apparatus constructed for discriminating diamond from ore was evaluated, and using minerals commonly occurring in diamond carrying ore as well as a wide variety of diamonds, it proved to function effectively. A significant improvement in the capability for diamond detection was found when pulsed lasers at 532 and 308nm were used, in comparison to the 532nm cw laser.

The purpose of this study was to examine attitudes and potential for sorting of food waste at restaurants in the central part of Umeå. The information was gathered through a questionnaire survey and by exploring different sorting methods. The questionnaire was sent to 55 restaurants and 24 of them responded. A majority of the respondents wanted to sort out food waste. 72.8 % believe they have a good or moderate potential to sort out food waste in the future and none of the respondents answered that they believed that they had no means of sorting out food waste. Overall, the restaurants are considered to have good attitudes about sorting food waste. However, this may be because the respondents have a better attitude than those who chose not to respond. The sorting methods were evaluated by reviewing reports written by government agencies and industry associations. Mill systems connected to a tank had the most pros and least cons of the sorting methods, but were expensive to install and required a lot of space. Sorting in individual containers was less expensive and required less space but was considered worse from a working environment standpoint. It seems that a combination of individual containers and a mill system connected to a tank suit most restaurants.