Fedotov

pp. 76-88

pp. 8-19

pp. 221-234

pp. 32-46

pp. 201-216

pp. 27-41

pp. 155-170

pp. 114-128

pp. 534-549

pp.148-161

pp.177-192

The paper concerns a laser fluorescence method for vegetation monitoring. It presents the experimental study results of laser-induced fluorescence spectra of plants in stress situations caused by improper watering. It is shown that at 532 nm wavelength of fluorescence excitation a stress factor impact may cause both a magnification of fluorescent signal and a deformation of fluorescence spectrum profile.  An identifying factor to characterize deformation of laser-induced fluorescence spectrum profile can be a relationship of fluorescence intensities at two wavelengths, i.e. 685 and 740 nm. Measurement of fluorescent signal intensity and fluorescence spectrum profile can be a basis of the laser fluorescence method to detect the plant stress situations.

The article describes an experimental setup for studying the laser fluorescence method for control of stress situations for plants. Fluorescence spectra of lawn grass are presented in normal and various stress conditions during fluorescence excitation at the wavelength of 532 nm induced by anthropogenic soil pollution. It is shown that influence of stress factors induced by soil pollution on plants transforms the fluorescence spectrum significantly; these results could be used as a basis for a new laser method for remote control of plants’ condition.

The article deals with classification of oil slicks on the earth surface. The authors provide experimentally obtained fluorescence spectra of pure oil and petroleum products; of various earth surfaces that are not polluted with oil; of oil and petroleum products spilled on various earth surfaces. It is shown that the use of the method based on detection of fluorescent radiation in five narrow spectral ranges allows to detect and classify oil slicks on the earth surface with probability of correct detection and correct classification close to one.

The article covers a laser method of measuring thickness of thin metal films on a transparent insulating substrate, based on the measurement of transmittance of a four-layer system "air (vacuum) - metal film - insulating base - air (vacuum)." Mathematical modeling results show that when measuring transmittance of a four-layer system "air (vacuum) - metal film - insulating base - air (vacuum)" at the wavelength of 515 nm, thickness determination of gold nanofilms on a quartz substrate is possible to a precision of  not more than 2% in the film thickness range  of 5 – 70 nm.

Experimental setup for studying the condition of plants by laser fluorescence method is described in this article. Fluorescence spectra of lawn grass in normal and stressful situations is also presented. It is shown that influence of stress factor on plants could lead to increase in fluorescent signal.

 In this paper the authors consider a laser reflectometric method of measurement of thickness of metallic films on dielectric substratewas. Optimal wavelengths for measuring thickness of gold nanofilms on quartz substrate were determined; error estimation for determining film thickness from laser reflectometry measurements was obtained. Mathematical simulation shows that the method allows to measure a gold nanofilm with thickness from 1 nm to 5 nm using wavelength 1310 or 1550 nm with mean error ~ 0,15 % and with thickness from 5 nm to 50 nm using wavelength 515 nm with mean error ~ 0,25 % and the relative root-mean-square value of measurement noise 1 %.

Laser monitoring problem of oil pollution at earth's surfaces was considered in this paper. It was shown that use of laser method based on detection of fluorescence radiation within four narrow spectral bands and hierarchical method of classification, allowed to classify oil pollution at earth's surfaces with a probability of correct classification close to one.

Article is devoted to experimental research of laser induced fluorescent spectrums of oil pollution on the earth’s surface. It was shown, that fluorescent spectrums of natural formations (earth’s underlying surfaces) and oil pollution had their own features which can be used to control oil pollution on the earth’s surface both right after spillage and at least a day after.

This article considers laser method of measurement of thickness and refraction index of a nanofilm on substrate. It is shown that the method based on determination of the first-order derivative of reflection coefficient allows to measure (with very few measurement errors) thickness and refraction index of a film at a measurement error of determination of reflection coefficient and first-order derivative of reflection coefficient by ~ 0,3 % in a wide range of refraction index (~ 3…7 and more) and thickness (~ 10…100 nm and more).