Extremal Problems and Quadratic Differentials

We study extremal problems for domains with free poles that belong to ray systems of points. __________ Translated from Neliniini Kolyvannya, Vol. 8, No. 3, pp. 298–303, July–September, 2005.     

Development of methods for ultrasonic scanning of X-ray wavelength

The method for X-ray wavelength tuning using an adaptive element (a quartz monolithic resonator modulated by a standing longitudinal low-frequency ultrasonic wave) has been proposed and implemented. This method is characterized by high tuning accuracy and possibility of scanning X-ray beam parameters with a time resolution of up to 3 μs.     

Evolution of X-ray rocking curves for paratellurite and lithium fluoride crystals under intense ultrasound

Local deformations of the crystal lattice under ultrasonic loading over a wide range of amplitudes have been investigated by means of recording the X-ray rocking curves for paratellurite and lithium fluoride single crystals.     

Accurate Control of Synchrotron Radiation Parameters Using X-ray Acoustic Longitudinal Resonators: Paratellurite (ТeO2) Crystals

Crystallography Reports - When carrying out experiments on the P23 beamline of the Petra III synchrotron source (Hamburg, Germany), high efficiency of X-ray acoustic longitudinal resonators for...     

New method for measuring rocking curves in X-ray diffractometry by ultrasonic modulation of the lattice parameter

A method for measuring double-crystal rocking curves with the aid of an X-ray-acoustic analyzer is proposed and implemented. This method makes it possible to perform precise measurements with a high time resolution and without the mechanical rotation of the crystal. The results of testing the method are presented.     

Rocking Curve Measurement for Deformed Crystals Using an Adaptive X-Ray Optical Bending Monochromator

A technique for recording rocking curves using an X-ray optical bending element is proposed to study the changes in the defect structure of single crystals under external impacts. The technique has been approved for a silicon crystal under a uniaxial mechanical load.     

Investigations of the Growth Processes of Bismuth-Germanate Crystals (Bi<Subscript>12</Subscript>GeO<Subscript>20</Subscript>) from the Melt using the X-Ray Diffraction Characteristics of Natural Lateral Faces

Single crystals of bismuth-germanate grown by the Czochralski method and possessing a combination of piezoelectric, electro-optical and magneto-optical characteristics are studied. The possibility of the non-destructive quality control of the grown crystals by X-ray diffraction investigation of their natural lateral faces is shown.     

X-ray acoustic resonators for controlling the spatial characteristics of X-radiation

The paper presents the results of studying the acoustic characteristics of special X-ray acousto-optical elements designed for precision control of X-ray beam parameters with time resolution. X-ray measurements revealed a number of specific features of oscillations of X-ray acoustic elements not exhibited in standard electromechanical measurements. The existence of these features is confirmed by numerical calculations computations of the acoustic fields in this type of elements.     

Some extremal problems in the theory of nonoverlapping domains with free poles on rays

We obtain new results on the maximization of the product of powers of the interior radii of pairwise disjoint domains with respect to certain systems of points in the extended complex plane. __________ Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 58, No. 12, pp. 1715–1719, December, 2006.