Jozef Kirkiewicz

Conditions for observation of the enhanced backscattering phenomenon in a turbulent atmosphere

Influence of enhanced backscattering effect on laser measurements of dust and aerosols content in a turbulent atmosphere is discussed. It is shown that doubling of the backscattered light intensity, characteristic for enhanced backscattering, leads to overestimating dust content in the air. To avoid undesirable effect of overestimation, it is recommended to displace receiving aperture sidewise relatively to laser source. Other method to eliminate overestimation is to use wider laser beam and extended receiving aperture as compared to coherence radius of the scattered wave field.

Influence of the electromagnetic wave polarization on surface impedance of metal

Our results consider the surface impedance of a metallic half space in the presence of the external magnetic field perpendicular to the surface. We consider a weak magnetic field and the strong one separately. The presented results include of Fermi liquid effects (the quasiparticles interaction), consequently they are valid only in low temperatures when the elastic electron scattering on the impurities is predominant. The shape of the integral terms of the impurity scattering operator allows distinguishing the difference between the transport mean free path from the mean free path. Because we take into account the kind of polarization of the electromagnetic wave, all calculations are made in the circular coordinates. Each part of the surface impedance has been separated to express exactly the influence of magnetic field and kind of polarization on the real part of impedance and on the imaginary one. All considerations are restricted to the isotropic metal model because the anisotropic case may be a matter of purely numerical calculations only.

Surface impedance in the anomalous skin effect regime

An analytical solution of the surface impedance is obtained using the kinetic equation with the collision integral that takes into account the Fermi liquid effects. It is assumed that the reflection of electrons is purely diffusive. Particular attention is paid to the influence of external magnetic field and polarization of the incident wave on the real and imagine part of the surface impedance.

Comparative studies of water turbidity on the grounds of a nephelometric method and diffraction effects

Water turbidity may be examined by measuring the scattered light intensity by suspended particles in comparison with the scattered light intensity in pattern solution that states for a nephelometric method. Water turbidity may be also measured with the use of monochromatic light beam absorption. But a diffraction method has found the broadest use. The method uses indicatrix of scattering as the sizes of the measured particles vary from 0.1 to 2000 μm. The examinations of the Odra River water turbidity have been performed on the basis of a diffraction method. Results of the examinations are plotted in graphs.

Investigation of the relations between the dust granularity and pollution concentration

Mechanism of light interaction with particles of dusts was presented in quantum aspect by analyzing differential cross section onto scattering. For rotational symmetry the differential scattering cross section was related with angle of scattering. One pointed on relation between the shape of indicatrix of scattering with size of scattered particles. Next a model of devices was introduced which makes possible a measurement of concentration of dustiness of the air oe gases and defines the sizes of dust grains on the basis of measurement of the scattered light stream.

Generalized optical methods for studies of inhomogeneities and pollutants in natural media

Starting from Maxwell electromagnetic equations one executed such kind of transformation, which make possible to express the energy of radiation by measurement of light intensity. The propagation of electromagnetic waves in heterogeneous medium we can treat as a process of multiple interaction of energy with particles of matter. If we use monochromatic source of light the interaction becomes univocal. The diffraction processes in heterogeneous medium form indicatrix of scattering, which shape introduces correlation between size of scattering particles as well as energy of scattered radiation. Got effects of measurement of energetic distribution can be used in processes of many technological fields, in which granulosis of product is measure of quality.

Distribution of intensities of light scattered on suspension particles

One marked the field of radiation of the electric dipole and next cross section on scattering. One analyzed the scattering lights on molecules not possessing of own dipole moment and then polar small particles. Treating the small parts of dust and of suspensions as elementary centers of scattering gone measured the angle distribution of scattered light intensity for selected size of particles. During measurements one used a monochromatic laser light researching scattering process in range of angle from 5 to 175 degrees.

Application of amplitude changes of monochromatic scattered light to investigation of dust grain composition

The light beam crossing the dust area meets with the loss of energy. We know by experience that the scattering indikatrix depends on the size of the dust particles. The measurement of the light energy scattered into given solid angle enables to identify and specification of the grain composition of the dust particles. Basis on the research a special head has been made to step change of the location of the photodetectors and in result to measure a specific or even desirable dust fraction for the sake of technology. In this paper the graphs of the grain dust distribution are presented with regard to the materials which are transported most frequently by Polish merchant marine.

Examination of the energy distribution of a laser beam scattered on dust particles at angles limited by meter discrimination and included in the scattering indicatrix

It has been pointed out that the shape of indicatrix of scattering laser beam on dust particles, assumed to be spherical, depends on grain size. This results from the fact that the angel of scattering is proportional to changes in interfering potential The device based on the above assumption can be measure granularity of particles with diameters scattering light at angles limited by the discrimination of the system. The measurement results presented graphically are repeatable and comparable with results obtained by professional instruments. Sericite dusts were used for reference in the investigation to be compared with dusts from most common types of cargoes carried by ships of the Polish merchant fleet.

Laser application in chosen maritime economy divisions

There has been described the method of making use of the Doppler effect in laser anemometrics, indicating that in order to define the frequency shifting, the method of heterodyne action for light beams passing through the area of examined flow has been used. The optics /scheme/ of anemometer has been shown, pointing at the arrangement of interference striae as the place of measurement. The radiation e mitted from the place of measuring location is recorded by photode tector, and then in the photodetector signal one can separate the basic signal and the frequency signal /Doppler signal!. The recorded curves, correspoding to the basic and Doppler signals, are passed on to the analysing and calculating block which displays the value of the flow velocity.