The main steps of creating the gravity gradiometers for the measurement of inhomogineasly of gravitational fields on different mobile carriers, including in conditions of space, are considered on the basis of the analysis of the open literature. The role of these devices in modern science and technology is described. There are the basic physical principles which allowed to create devices that are actually used at the moment. The basic parameters of these devices characterizing their quality are also described. The aim of this study is to establish the basic problems that have to be solved to create these instruments, as well as obstacles to their widespread adoption in the various areas of science and technology and to formulate the basic tendencies and state of development at the moment. It is shown that the existing devices are too expensive, heavy and massive to be used widely on the Earth and in space. Here is described the desire of developers to create more simple, reliable and low-budget devices, which primarily intended for using in micro satellites is described here. It is concluded that the development of gravity gradiometer based on micromechanical and electromechanical technologies currently can not overcome the problems associated with noises inherent such instruments. This study in some ways is the rationale for the following work of authors, which sets out the principles of the new gravity gradiometer, which may help to solve some of the problems are described here.

Coolant flow mixing processes with different temperatures and concentrations of diluted additives widely known in nuclear power units operation. In some cases these processes make essential impact on the resource and behavior of the nuclear unit during transient and emergency situations. The aim of the study was creation of measurement system and test facility to carry out basic tests and to embed spatial conductometry method in investigation practice of turbulent coolant flows. In the course of investigation measurement system with sensors and experimental facility was designed, several first tests were carried out. A special attention was dedicated to calibration and clarification of conductometry sensor application methodologies in studies of turbulent flow characteristics. Investigations involved method of electrically contrast tracer jet with concurrent flow in closed channel of round crosssection. The measurements include both averaged and unsteady realizations of measurement signal. Experimental data processing shows good agreement with other tests acquired from another measurement systems based on different physical principles. Calibration functions were acquired, methodical basis of spatial conductometry measurement system application was created. Gathered experience of spatial sensor application made it possible to formulate the principles of further investigation that involve large-scale models of nuclear unit equipment. Spatial wire-mesh sensors proved to be a perspective type of eddy resolving measurement devices.

In order to solve the problem of continuous or periodic monitoring of water areas affected by radioactive contamination in the result of scheduled emissions in nuclear power plants or in the result of emergency situations in nuclear fuel cycle plants we need to develop measurement instruments with advanced mathematics and program support to assess the level of radioactive contamination with required accuracy. The aim of theoretical research was to optimize detection device construction, estimate spectrometer metrological parameters in given measurement geometries, and determine effective position of detection device in the process of in situ measurements. This device consists of spectrometric scintillation probe packed into sealed container (detection device) based on NaI(T1) crystal of Ø 63 × 63 mm or Ø 63 × 160 mm size, cable reel with deep-sea cable and a tablet PC for data processing and displaying. The container withstands static hydraulic pressure up to 5 MPa and can be used for measurements at depths of 500 m maximum. Probe measures energy distribution of gammaradiation with energy from 70 keV to 3000 keV. The implemented three-dimensional system for detection device position and orientation determination allows automatic operation of the device (without operator) for water areas or bottom sediment scanning. The spectrometer can output measurement results with threedimensional geographical coordinates as index maps of distribution with necessary resolution and accuracy. Monte Carlo models of spectrometer and controlled objects are developed in order to determine the detector response functions to given radionuclides in given measurement geometries without use of expensive standard measures of activity. Multifunction gamma-spectrometer for in situ radiation monitoring of water areas and bottom sediments was developed and constructed. In the result of theoretical researches the response functions have been calculated in the form of theoretical spectra of monitored radionuclides in definite measuring geometries. The results of mathematical modeling of the gamma-emitting transfer process allowed to estimate effective position of detection device for in situ measurements of specific activity radionuclides ¹³⁴Cs and ¹³⁷Cs in bottom sediments. 

Instruments for spectral filtration of images are an important element of the systems used in remote sensing, medical diagnostics, in-process measurements. The aim of this study is analysis of the functional features and characteristics of the proposed two image monochromator versions which are based on dispersive spectral filtering. The first is based on the use of a dispersive monochromator, where collimating and camera lenses form a telescopic system, the dispersive element of which is within the intermediate image plane. The second version is based on an imaging double monochromator with dispersion subtraction by back propagation. For the telescopic system version, the spectral and spatial resolutions are estimated, the latter being limited by aberrations and diffraction from the entrance slit. The device has been numerically simulated and prototyped. It is shown that for the spectral bandwidth 10 nm (visible spectral range), the aberration-limited spot size is from 10–20 μm at the image center to about 30 μm at the image periphery for the image size 23–27 mm. The monochromator with dispersion subtraction enables one to vary the spectral resolution (up to 1 nm and higher) by changing the intermediate slit width. But the distinctive feature is a significant change in the selected central wavelength over the image field. The considered designs of dispersive image monochromators look very promising due to the particular advantages over the systems based on tunable filters as regards the spectral resolution, fast tuning, and the spectral contrast. The monochromator based on a telescopic system has a simple design and a rather large image field but it also has a limited light throughput due to small aperture size. The monochromator with dispersion subtraction has higher light throughput, can provide high spectral resolution when recording a full data cube in a series of measuring acts for different dispersive element positions. 

Manufacture of module of chemical sensors on a single chip is one of the promising directions in the development of gas sensory. The aim of this work was development of construction of multisensor microsystem enabled to retain the characteristics of a single sensor and its dimensions and, at the same time, to reduce power consumption and cycle time of measuring concentration of gases CO, H₂ , C₃H₈ , CO₂ in the environment. Multisensor microsystem consists of four detached sensors placed on a single substrate of nanostructured aluminum oxide. The use of through-holes and the dielectric substrate itself in microsystem topology reduced power consumption of gas microsystems. We have devised a method of measuring sensitivity of foursensor microsystem to the concentration of gases CO, H₂ , C₃H₈ , CO₂. A full cycle of measuring gases concentration consisted of the time required for preliminary heating of all sensors of the microsystem (5 s), the heating time of each of the sensors sequentially (5 s) and time required to measure resistance for each sensor (80 s). The measured results show that the reaction time of multisensor microsystem when exposed to gases – H₂ at a concentration of 0,001 %, CO2  1 %, СО – 0,02 %, C₃H₈ – 0,01 % does not exceed 90 s for full measurement cycle. Sensitivity value at power consumption of < 150 mW makes up 48–64 % for H₂ , 32– 36 % for CO₂ , 20–29 % for СО, 68–78 % for C₃H₈ . The proposed method to control sensitivity of multisensor microsystem to the concentration of gases CO, H₂ , C₃H₈ , CO₂ allows performing measurements within 90 s while the measurement cycle by a single sensor in pulse heating mode is 2 min, in continuous heat mode – 5 min. Maximum power consumption of the microsystem does not exceed 150 mW. Microsystems allow measuring lower concentrations of detected gases. 

Transition of the precision engineering and instrumentation to the widespread use of nanoscale structures and thin layers requires improved localization methods for measuring the depth of the material. Unified standards and the generally accepted methods for measuring the wear resistance and friction coefficient are not currently available. The aim of this work was the development of a universal friction machine with the simplified requirements for the preparation and the geometric shape of the sample and the opposing disc. An important requirement for the equipment and the method of measurement is the ability to measure the friction coefficient and the determination of the wear resistance of coatings and hardened layers of micron and submicron thicknesses. Another important requirement is modeling in the experiment of acyclic friction process, as close as possible to the real operating conditions of components and parts. Both of these conditions are successfully realized by using the method of «disc on plate». Implementation of «disk on plate» method was used to simplify and improve the rapid measurement, and to minimize load on the friction assembly, reduce friction pair temperature, increase the sensitivity and improve the resistive bridge thermal stabilization. The complex for the study of friction and wear processes of various materials pairs in conditions close to operational was manufactured and tested. The measuring console with a low value of the parasitic load on the measuring cell was designed. A computerized hardware and software system for the registration of the friction parameters of the process was developed. The software for processing and storage of experiment results was developed. The software is compatible with modern Windows operating systems. The file format for measurement results storage is compatible with the conventional graphic editors and could be processed by means of Exсel. The main principles of the analysis and processing of the results are consequentially described. Typical results of usage of the developed machine for friction coefficient measurements and the determination of the wear resistance of massive, homogeneous surfacehardened materials and alloys with coatings are shown. The high efficiency of the created equipment complex during investigation of coatings, optimization of coating depositing processes and the modification of the surface layers are shown in the study. The efficiency of the complex was confirmed by the study of the modified layers and micron thickness coatings. It was found that the friction coefficient and wear resistance of construction materials, modified thin microcrystalline layers and nanostructured coatings was effectively controlled by using of the created complex. 

Laser pulse simulation of the surface waves and its receiving by contact piezoelectric probes is perspective direction to detect surface defects. The aim of this work was to determine optimal conditions for detection of the real fatigue cracks of nearly microns width and surface pores by moving depending on the position of the center of a laser beam laser beam spot. The objects of research were metal specimens with crack’s width of 8 m up to 0,5 mm and depth ≈ 400– 500 mm up to ≈ 200 mm. Cylindrical hole by ≈ 1 mm diameter used as a model pore. An experimental installation used consisted of the pulse laser light emission source with laser wavelength of 1.06 m and laser pulse duration of ≈ 20 ns. An arrangement to adjust the laser beam spot geometry in the form of a long strip and a circle was applied. Surface waves were received by the 2.7 MHz frequency probe, and processed with use of a «Spectronic» TDS 3052B oscilloscope. The laws of acoustical signal amplitude and its form changes vs. the laser beam spot geometry and its position in regard to defect were determined. We discovered that optimal conditions for flaw detection took place when the laser beam spot moving trough the defect’s range – crack and pore. In the first case amplitude growth of the signal was up to 7–8 time – like as resonance conditions realized. And the ratio of the laser’s beam spot width (as long strip) to wave length were ≈ 1.8–2.2. The more informative parameter to find crack with small width (≈ 0.5mm) was the acoustical pulse spectrum or the pulse entrance part. Thus, the further increasing of the surface flaw detection may be realized by laser simulation of the surface waves controlling the form of the moving spot of laser beam. New possibilities to increase sensitivity and reliability of ultrasonic evaluation surfaces in objects with complicated profile and fare accessible places are to be arise.

Medical, and technological linear particle accelerators, and nuclear reactors are vastly widespread worldwide today. These facility generate fields of secondary gamma radiation with energy to 10 MeV. Therefore, we have a need to calibrate spectrometric and dosimetric ionization measurement instruments for the energies to 10 MeV. The aim of this work is to determine possibility to use thermal neutron collimator of АТ140 Neutron Calibration Facility with 238Pu-Be fast neutron source (IBN-8-6) for this. Below 3 MeV we use a set of point gamma standard spectrometry sources OSGI. We can acquire gamma rays with energies above 3 MeV using radioactive thermal neutron capture on target, i.e. (n, γ)-nuclear reaction. We can use neutron capture gamma-ray from titanium target (to 7 MeV) or nickel target (to 10 MeV) situated in thermal neutron field for calibration. We can use thermal neutron collimator of АТ140 Neutron Calibration Facility with 238Pu-Be fast neutron source (IBN-8-6) for slowing down neutrons from radionuclide fast neutron sources to thermal energies in polyethylene. Thermal neutron collimator forms a beam from radionuclide source with a significant amount of neutrons with thermal energies. We placed Ti and Ni targets in collimator’s canal. We got experimental spectral data on detection unit BDKG-19M NaI(Tl) 63 × 160 mm with nonlinear channel-energy conversion characteristic in range to 10 MeV. For additional filtration we proposed to use polyethylene neutron reflector and lead discs. We experimentally determined that placement of lead discs in collimator in front of the target allows to filter all spectrum while insignificantly weakening target’s emission. Using theoretical and experimental data we proved the ability to calibrate gamma-ray spectrometers in the range to 10 MeV. 

The aim of this work was to estimate limitations related of the actual resolution of images taken into the object reconstruction procedure (using Structure from Motion method) applied for anthropometric measurements. This is necessary to define technical parameters of equipment used for this application. A series of 42 images of the sample static object were taken with use of high resolution camera. The object was in a stable position, properly illuminated with stable, diffused light sources. With use of VisualSFM software a virtual cloud of points representing real points of examined object was calculated. During tests a resolution of input images were changed then the calculation time and influence of the number of points in the cloud onto deviation of selected anthropometric parameters were analyzed. In conditions of the performed experiment decreasing of the resolution of input images to the level of 80 % of initial value (or lower) has significant influence onto results of the measurements of selected anthropometric parameters. Structure from Motion (SfM) technique can be adopted for anthropometric measurement systems when the input images are taken with high resolution imaging device (over a dozen of million pixels). Presented measurement method for anthropometry is characterized by ease of use, do not need any calibration before measurements or specialized equipment. Thank to this can be adopted in practice in any conditions and operated by unskilled operator. 

The aim of this work is the analysis of the influence of annealing in an inert atmosphere on the electrical properties and structure of non-stoichiometric tin dioxide films by means of impedance spectroscopy method. Non-stoichiometric tin dioxide films were fabricated by two-step oxidation of metallic tin deposited on the polycrystalline Al₂O₃ substrates by DC magnetron sputtering. In order to modify the structure and stoichiometric composition, the films were subjected to the high temperature annealing in argon atmosphere in temperature range 300–800 °С. AC-conductivity measurements of the films in the frequency range 20 Hz – 2 MHz were carried out. Variation in the frequency dependencies of the real and imaginary parts of the impedance of tin dioxide films was found to occur as a result of high-temperature annealing. Equivalent circuits for describing the properties of films with various structure and stoichiometric composition were proposed. Possibility of conductivity variation of the polycrystalline tin dioxide films as a result of аnnealing in an inert atmosphere was demonstrated by utilizing impedance spectroscopy. Annealing induces the recrystallization of the films, changing in their stoichiometry as well as increase of the sizes of SnO₂ crystallites. Variation of electrical conductivity and structure of tin dioxide films as a result of annealing in inert atmosphere was confirmed by X-ray diffraction analysis. Analysis of the impedance diagrams of tin dioxide films was found to be a powerful tool to study their electrical properties.