Evaluation of Raman spectroscopy for the analysis of colored fibers: a collaborative study

A collaborative study on Raman spectroscopy was carried out by members of the ENFSI (European Network of Forensic Science Institutes) European Fibres Group (EFG) on three dyed fibers: two red acrylics and one red wool. Raman instruments from six different manufacturers were tested as well as nine different laser wavelengths ranging from blue (lambda = 458 nm) to near infrared-NIR (lambda = 1064 nm). This represents the largest comparison study of Raman analytical parameters carried out on identical fiber samples. For the chosen fiber and dye samples, red lasers (lambda = 633 and 685 nm) gave the poorest spectral quality whereas blue (458 nm), green (514 nm) and near infrared lasers (785, 830 and 1064 nm) provided average results. Blue (488 nm) and green lasers (532 nm) globally gave the best quality spectra. Fluorescence problems were often encountered with some of the excitation wavelengths and therefore a flexible Raman instrument equipped with different lasers can be recommended to measure forensic fiber samples. The instrument should also be equipped with a Raman microscope in order to be able to focus on a single fiber. This study shows that Raman spectroscopy usually enables the identification of the main dye present in a colored fiber; however, minor dye components are much more difficult to detect. SERRS (Surface Enhanced Resonance Raman Scattering) techniques give an improvement of the dye's spectral intensity but no spectral improvement was observed for the two red acrylic and red wool fibers tested.     

Democratization without decentralization: Local government in Hong Kong

The literature on democratization tends to neglect the question of decentralization. The case of the Hong Kong Special Administrative Region (HKSAR) of the People's Republic of China shows that there can be partial democratization without decentralization. Democratization in Hong Kong took place in the mid‐1980s and 1990s, when more directly elected seats were introduced to political institutions at the territorial, municipal and district levels. However, democratization has not been accompanied by an attempt to decentralize administrative and political power to the institutions at the local level. These political institutions, including the Urban Council (UrbCo), Regional Council (RegCo) and District Boards remain relatively weak vis‐à‐vis the executive branch of the government. The recent attempt by the HKSAR government to abolish the UrbCo and RegCo represents a move toward centralization of administrative and political power. Moreover, District Boards remain consultative and politically powerless. It is the dynamic relationship between democratization and decentralization at which future research should be directed.