The bacteriorhodopsin film in gelatin matrixes which are used as sensitive elements of integrated optic and fibre-optic sensors of various vapor and gases components will not be able to carry out the chemical control of aqueous solutions. In the given paper the results of technological development of obtaining the bacteriorhodopsin (bR) films in a sol-gel matrix are represented. The films are obtained in a broad thickness range (from 0.5 to 20 microns) with various bR concentrations and photosensitize additives. The optimal technological conditions of obtaining of uniform films with given optical parameters are defined. The surface morphology and cross section of the obtained films was studied using an AFM and SEM. The films have a reasonable surface roughness (~ 100 nm) and a uniform distribution of the purple membrane fragments in the nanostructured sol-gel glass matrix along the films surface and thickness. The transmission spectrums have the characteristic for bR the absorption band, the value of which depends on bR concentration and technological features of the films deposition. The investigated photosensitive properties of the obtained films and influence on them of chemical components of aqueous solutions, allow recommending the thin bR films in sol-gel matrixes for creation of planar waveguides in the role of components of the chemical sensors of liquid solutions.
All-optical switching using an optical fibre long-period gating (LPG) modified with bacteriorhodopsin (bR) is demonstrated. The switching process is based on the photo-induced RI change of bR, which in turn changes the phase matching conditions of the mode coupling by the LPG, leading to modulation of the propagating light. The effect was studied with an LPG immersed into a bR solution and with LPGs coated with the bR films, deposited onto the LPGs using the layer-by-layer electrostatic self-assembly (LbL) method. The dependence of the all-optical switching efficiency upon the concentration of the bR solution and on the grating period of the LPG was also studied. In addition, an in-fibre Mach-Zehnder interferometer (MZI) composed of a cascaded LPG pair separated by 30 mm and modified with bR was used to enhance the wavelength range of all-optical switching. The switching wavelength is determined by the grating period of the LPG. Switching efficiencies of 16 % and 35% were observed when an LPG and an MZI were immersed into bR solutions, respectively. The switching time for devices coated with bR-films was within 1s, 10 times faster than that observed for devices immersed into bR solution.
The paper deals with the issue of compiling the Southwestern dialect dictionaries. A survey of the history of the dialect dictionaries from the mid-nineteenth century to the present is given. The scientific background and principles of compiling the dictionaries in question are analyzed. Special attention is given to dictionary register, dictionary entry structure, description of semantic properties of registered words, illustrative material, word passport.
It has been established that many aspects of the Hutsul dialects are reflected in different lexicographical works, though a big academic dictionary still needs to be written. There exist big differential dictionaries of the Boyko, Bukovynian, Upper Dniestrian dialects. The Transcarpathian and Lemko dialects are less closely studied in this respect. There have been carried out some lexicographical studies of the Podillian, Pokuttian, Southern Volynian dialects and the dialects of the Sian river basin; further research is certainly needed to provide a firm basis for compiling dictionaries of these dialects.
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