We present a novel universal method for determination of phosphorus and organochlorine pesticides, synthetic pyrethroids and triazoles in plants: cereals, legumes and oilseeds. The technique is based on QuEChERS method of sample preparation followed by purification of the extracts by natural aluminosilicate and determination of the analytes using gas chromatography-mass spectrometry. Accuracy of the procedure is checked in spiking tests. The relative standard deviation is less than 0.05. The advantages of the proposed method are good metrological characteristics, easy implementation, affordability and replaceability of imported sorption materials. The technique can be used in practice of the laboratories engaged in quality monitoring of plants.

Modernization of the pulse discharge generator and analytical signal recording unit is performed on the basis of new electronic components and hardware. Optimal operation parameters of the analytical device are specified. Metrological characteristics of hydrogen determination in the range of 0.001 -0.1 wt.%. in titanium alloys using the modernized mounting are listed.

Highly sensitive colorimetric technique is developed for measuring iron and chromium content in monopotassium phosphate at a level of 10⁶ wt.%. Study of kinetics of iron (III) reduction by hydroxylamine hydrochloride in phosphate media with different revealed that optimal absorbance of iron(II) - 1,10-phenantroline complex correlates with iron concentration in the sample within pH range 7.0 - 7.5. Coloring stability in time is also studied. Proposed blank sample preparation technique eliminates the impact of suspended particles present in the sample on the optical density value. The results obtained by colorimetric method are compared to data of atomic emission spectrometry, analytical target profile of the technique being also assessed.

We present the results of studying metrological characteristics and comparative analysis of the data of electron probe determination of the composition of rare earth minerals and synthetic compounds obtained both by wavelength-dispersive (WDS) and energy-dispersive X-ray spectrometry (EDS). The measurements are carried out on a JXA-8100 (Jeol) micro-probe with three wave spectrometers and energy-system “Link Pentafet” with “INCA Energy 400” software (Oxford Inst., UK). The results demonstrated the effectiveness and reliability of microprobe EDS method in analysis of rare earth minerals. EDS and WDS are comparable in accuracy upon determination of the major and minor components of rare earth minerals, whereas for trace elements (below 1 wt.%) EDS is substantially behind WDS method.

A new approach to description of the phase structure of heterogeneous alloy is exemplified in the study of high-chromium cast iron using optical and mathematical analysis. The evaluative parameters are developed proceeding from mathematical processing of metallografic images of the structures of heterogeneous alloys. The parameters provide consideration of the degree of inhomogeneity of the identified phases. The proposed method can be used both for rapid analysis, or as a part of complex structure analysis that may also include various scientific methods for more accurate study the structural components in the local areas of heterogeneous alloys with allowance for thermodynamic processes occurring upon crystallization and heat treatment.

An improved method of determining the amount of carbon and degree of tetragonality in the surface layers of carbon steels subjected to a plasma hardening. The method is based on analysis of the shift of martensite diffraction line (222) in plasma reinforced steel against the line position in the annealed steel of the same chemical composition thus providing determination of the degree of martensite decomposition upon overlapping of adjoining bands. We demonstrated a possibility of determining the degree of martensite tetragonality and carbon content in martensite without the necessity of extracting powder of the hardened layer. A possibility of using the technique for studying the surface layers obtained by plasma hardening and other strengthening procedures is demonstrated.

A mathematical model of the alloy flow curve in adiabatic conditions of deformation is developed. The dependences of the modulus of resilience and yield stress from the shear strain are obtained. We propose to use the maximum value ofthe yield strength corresponding to alignment of the intensities of hardening and softening as an indicator of the resistance of the material upon cutting. Examples of the flow curves obtained for cutting steels 45 and 35Kh3NM are presented.

A method for determination of the confidence limits of the fatigue curve based on linear regression analysis is considered to provide forecasting of the durability of samples at a given probability of non-destruction. A specific example of using the method demonstrated that at fixed stresses the real laws of the durability distribution of the samples are described rather poorly by parametric statistics and the number of strain cycles prior to destruction thus forecasted does not correspond to the probability of their non-destruction which leads, in turn, to significant error in calculation of the confidence limits. We present an original algorithm of determining the confidence limits of fatigue curve using nonparametric statistics. The developed algorithm provides estimation of the systematic error of fatigue test data processing by the methods of linear regression analysis.

Features of the unique testing machine developed at the Research and Development Institute for constructional materials “NlIgrafit” are considered. The unit is intended for studying the mechanical properties of carbon and carbon-carbon composite materials (CCCM) tested for tension, compression and bending within a temperature range from 20 to 3000°C. The strong points in the designs of furnaces and dilatometers used in testing machine for measuring the longitudinal displacement of the samples upon determination of the elastic-deformation characteristics of the materials under study are described. Designs of the original reversers used for testing samples for compression and bending are also considered. The necessity of using non-standard shaped samples in tests for compression (in the form of a coil) and specimens with elongated heads in tensile tests of carbon-carbon composite materials is shown. Thus we managed to determine not only the strength but also elastic-deformation characteristics of carbon and carbon-carbon composite materials in a temperature range 20 - 3000°C.

Wear resistance of the layer obtained upon plasma hardening of steel 65G on a UDGZ-200 serial unit in conditions of dry friction is shown to increase unevenly. At a distance up to 1.0 mm in depth (zone of complete hardening) the wear resistance increases by 6.6 - 9.0, whereas at a depth of 1.3 - 1.9 mm (incomplete hardening) the wear resistance gradually decreases to the level of unhardened metal. Thin surface layer (about 30 μm) is directly damaged by plasma arc and thus has reduced wear resistance. The wear resistance of the indenter made of hardened steel is 1.4 times lower when used in friction tests on completely hardened surface compared to that on unhardened metal

The use of kernel estimations in determination of the probability density and smoothing of the sequences is considered. Condition of the equality of the estimates of several central moments of the sample and moments determined for kernel estimation of the distribution density is used in the first case, the choice of the fuzziness index being thus simplified. Additionally, separate approximation of the branches of density estimations is used. The method of mode filtration is proposed to be used for smoothing the sequences. Determination of the smoothed value as an argument corresponding to the maximum of the density distribution estimation for the local section of the sequence provides tracing of the abrupt changes in the mean value of sequence and sift impulsive noise.

A possibility of using Text Mining methods for the tasks previously solved by expert procedures is demonstrated. We consider the issues attributed to determination of the scientific novelty of publications and identification of originating technological trends using Text Mining. We also consider the specificity of the problems and their possible solutions, formulate the problem and review the methods used in literature. Methods of automated detection of words-markers which characterize the scientific novelty and their use in creation of specialized templates are studied. The samples containing documents which underwent expert estimations are formed and described to develop the technique of template construction. The results of practical use of the templates thus obtained on the base of analysis of the publications in the field of Computer Science are discussed.