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Laser-induced fluorescence KA-14 LIDAR, developed and employed at the National Aviation Academy of Azerbaijan was used for detection of emission spectra of oil spills on the surface of the Caspian sea and earth surface of the Absheron peninsula. It is known, that oil spills may take place due to leakage of oil from different Oil-Gas-Production Companies and Joint Ventures of the State Oil Company of Azerbaijan Republic. There are 8 Oil-Gas-Production Companies and 4 Joint Ventures in Azerbaijan Republic. Fluorescence spectra were excited by 355 nm line of CFR 200- type laser (QUANTEL) with parameters: diameter of laser beam spot- d = 5 mm (after collimation- 40 mm); frequency of excitation- f = 20 Hz; pulse duration and power of laser- τ= 7 ns and 60 mJ, respectively. Analysis of differences of the spectral positions of maximums of fluorescence spectra, forms of the emissions spectra, as well as peculiarities of fine structures in emission spectra allowed with a high degree of availability to determine from which Oil-Gas-Production Company of State Oil Company of Azerbaijan Republic (including OGPC “Neftjanije Kamni”) leakage took place on the surface of the Caspian sea and on the earth of Absheron peninsula. Results obtained allow, for the first time, to create a data bank of fluorescence spectra of crude oil extracted on the earth of the Absheron peninsula of Azerbaijan as well as from adjacent water areas of the Caspian sea, including OGPC "Neftjanije Kamni."

GaSe-type crystals have attracted increasing attention because of pronounced structural anisotropy, unique optical and Nonlinear Optical Properties, which may lead to numerous applications in light generation (second harmonics and tuning in a wide transparency range of λ= 1÷20 μm) and optoelectronics (radiation detectors, photovoltaic energy converters, photo-resistors, light modulators etc.). In the present work, damage threshold of the Bridgman grown GaSe and its structural analogs ((GaSe1-x Sx (where 0 ≤x ≤0.25, InSe and GaTe)), have been investigated under IR τ = 5 ns pulses (λ= 1.064 μm) of "QUANTELL Brilliant b" laser (pulse energy ~ 850 mJ, f = 20 Hz). For all studied crystals occurrence of local micro defects and pulse induced heating were identified to be responsible for damage threshold mechanism. Results for GaSe obtained in the present work are in good agreement with published in literature for damage threshold excited with laser lines in the spectral range of λ= 1.1 ÷ 2.9 μm lines of the Optical Parametric Generator. The values of damage threshold for solid solutions of GaSe1-x Sx, InSe and GaTe crystals are reported for the first time.

Influence of Ag nanoparticles on optical and photovoltaic properties of, silicon substrates, silicon solar cells and glass have been investigated. Silver nanoparticles have been fabricated by evaporation of thin Ag layers followed by the thermal annealing. The surface plasmon resonance peak was observed in the absorbance spectrum at 470 nm of glass with deposited silver nanoparticles. It is demonstrated that deposition of silver nanoparticles on silicon substrates was accompanied with a significant decrease in reflectance at the wavelength 360-1100 nm and increase of the absorption at wavelengths close to the band gap for Si substrates. We studied influence of Ag nanoparticles on photovoltaic characteristics of silicon solar cells without and with common use antireflection coating (ARC). It is shown that silver nanoparticles deposited onto the front surface of the solar cells without ARC led to increase in the photocurrent density by 39% comparing to cells without Ag nanoparticles. Contrary to this, solar cells with Ag nanoparticles deposited on front surface with ARC discovered decrease in photocurrent density. The improved performance of investigated cells was attributed to Ag-plasmonic excitations that reduce the reflectance from the silicon surface and ultimately leads to the enhanced light absorption in the cell. This study showed possibility of application of Ag nanoparticles for the improvement of the conversion efficiency of wafer-based silicon solar cells instead of usual ARC.

Remote sensing of contaminations on water and earth surfaces (oil spills, films) taking place during oil-gas extraction is an interesting and actual problem. This problem may be solved by using different methods of optical spectroscopy, including: •Raman scattering; •light induced breakdown spectroscopy (LIBS); •fluorescence spectroscopy. Fluorescence Light Detection and Ranging (LIDAR) LIDARs are successfully used for remote sensing of chemical and biological substances at atmosphere. A new laser induced fluorescence (LIF) KA-14 LIDAR system for detecting of oil spills on the sea surface was employed at the National Aviation Academy of Azerbaijan. LIDAR’s parameters are as follows: •laser CFR 200- type QUANTEL, λ = 355 nm, beam O = 5.35 mm, f = 20 Hz, pulse duration τ = 7 ns, pulse power 60 mJ; •diameter of Newtonian- type telescope is 200 mm; •collimator expansion of the laser beam diameter- not less than 3; •angle range of telescope measurements relative to horizon: from -20 to +20 degree; •spectral range of measurements: from 380 to 750 nm, number of spectral channels- 32; •maximum range of measurements- not less than 250 m. This LIDAR is the first performing these kind of research not only on the Azerbaijan beach of Caspian sea, but also on the earth places of Absheron peninsula, where oil-gas production takes place. We hope that the performance of LIDAR will have an International recognition and will make noticeable input on the International Research of Caspian sea surfaces.

The article surveys the ethical and social issues that arise from recent developments in assisted reproductive technologies (ART) involving cryotechnology and argues that practitioners must understand ethical as well as technological issues. It discusses the risks associated with ART and the importance of the need to inform patients of them so that they can make considered decisions. It considers problematic areas in the use of ART, particularly the case of lesbian women who wish to conceive. It offers a philosophical definition of ethics and a framework for defining ethical, and unethical, clinical practice. It advocates a utilitarian approach to moral problems, one that attends to the moral consequences of actions. It examines the complex way that morality, law, and ethics interact and refers to controversial legal decisions in the United Kingdom concerning ART. This article considers the various rights (of donors, prospective parents, and offspring) that need to be taken into account by practitioners of ART.

Background: Semen cryopreservation is a widely available method of maintaining fertility in male cancer patients. However this facility is not always used. Aims: To identify the barriers to successful sperm banking in a group of adolescent and young adult patients. Methods: Questionnaires were administered to 55 patients aged 13–21 years who had received potentially gonadotoxic therapy between 1997 and 2001 and had been offered sperm banking. Results: Forty five questionnaires were completed; 67% of respondents were able to bank sperm. Those who had been unsuccessful were younger and described higher levels of anxiety at diagnosis and greater difficulty in talking about fertility. They also described less understanding of sperm banking at the time of diagnosis. Conclusion: Most adolescent cancer patients who have been offered fertility preservation are able to bank sperm. Younger patients may be helped by the provision of high quality information and more open discussion of the technique.

Semiconductors with the common composition II-III2-VI4 (where II are divalent cathions; III – trivalent cathions and VI – chalcogenides) are perspective materials for optoelectronics. The electrical properties, luminescence, photoconductivity and thermally stimulated depolarization of these compounds have been investigated MnGa2Se4, MnGa2S4, MnIn2S4, MnGaInS4 and PbGa2Se4 compounds possess high photosensitivity. CaGa2S4 doped with rare-earth elements have been found to be effective luminescent semiconductor materials.