Two methods of acid decomposition (in an open system and autoclave-cured decomposition) suitable for large scale analysis of rocks, soils, ground and bottom sediments using atomic emission (AE) and inductively coupled plasma mass spectrometry (ICP-MS) are developed. We propose a method of using domestic highly enriched stable isotopes, which, although with limitations, provides control ofthe dissolution phase of for each test sample.

A technique of gas chromatographic determination of the derivatives of methyl-phosphonic acid: O-isopropylmethylfluorophosphonate (sarin), O-1,2,2-trimethylpropylmethylfluorophosphonate (soman), O-isobutyl-S-[2-(N,N-diethylamino)ethyl]methylthiophosphonate (Russian Vx, RVx), O-methyl-O'-isobutylmethylphosphonate (DAMF) is developed. The method suggests the use of a detector of thermal conductivity. The method of internal standard is used for quantitative calculations. The error ofthe methods is below 3%, time of analysis is 40 min.

To reduce the detection limit of gold determination by atomic absorption spectrometry with atomization (ETAAS) in iron-containing materials, we propose to use dispersion microextraction with chloroform of ion associates AuCl⁴ with a cation of brilliant green. Optimal conditions of microextraction which provide 96% of gold recovery (two-fold extraction) are specified. The developed ex-traction-ETAAS procedure of gold determination is used in analysis of sedimentary rocks (shale pyrite) and oxidized (secondary) polymetallic ore containing 7 and 37% iron, respectively. The detection limit is 0.0002 mg/kg ;the relative standard deviation does not exceed 0.2.

Processes that occur in heat affected zone (HAZ) upon heating and cooling of metal ofwelded joint upon local heat treatment (LHT) in normalizing mode are simulated. For cooling rates used in workshop conditions critical points are determined for steels of different chemical composition. Novel LHT modes are developed for different pipe steels capable of increasing the impact toughness due to formation of small austenitic grains after heating and uniform fine-grained ferrite-pearlite microstructure in welded joint after cooling. The results are tested and imlemented in production of electric-welded tubes 114 - 530 mm in diameter (K50 - K60 pipe grades, according to API standard) at the JSC “Vyksa Steel Works.”

The results of studying the structure and mechanical properties of VT8-1 alloy subjected to different heat treatment procedures are presented.The phase com position and morphology of the precipitating phases are determined using transmission electron microscopy. It is shown that temperature elevation at the first stage of annealing leads to an increase in the strength properties and fracture toughness due to increased dispersion of the secondary and tertiary precipitates of а-phase. The width and morphology of a-plates, and the ratio of primary and transformed (secondary) а-phase depends on the initial (a + ß) state, and hence on the selected processing temperature at the high temperature stage with respect to the temperature of polymorphic transformation. The formation of the complex of structural characteristics is also affected by the nature of the discharge and the size of the titanium silicides near the interphase boundaries.

We specified an algorithm of determining the SHF dielectric permeability (DP) upon heating in a cylindrical guide cavity. It is shown that uneven heating and different thermal and physical conditions of measuring the inherent parameters of the cavity with and without the specimen are the main sources of errors in determination of dielectric permeability. The developed algorithm of DP calculation upon heating includes an integral expression for determination of the electric length of the cavity with allowance for unevenness of heating which provides improved accuracy in determination of the temperature dependence of dielectric permeability.

A technique for determination of the specific conductivity of complex aqueous electrolyte solutions containing the admixtures is developed. Capillary cell of a contact type with three platinum electrodes and AC bridge R5083 ensure a wide frequency range (0.1 - 100) kHz of measurements with a reative accuracy of 0.01 %. Calculation of the electrical conductivity with allowance for the polarization impedance is performed using the method of the cell constant variation (CCV). A comparison between CCV results and data obtained by frequency method revealed that the discrepancy with the literary data does not exceed 4 %. Testing of method and measurements are carried out using reference KCl solutions 0.1 and 1 mol/kg in a temperature range of 20 - 70 °C.

We developed a method and a set of measuring devices for rapid determination of the apparent and real densities of structural graphites and carbon-carbon composites and compared the results with the corresponding data of conventional procedures. The values of the apparent density obtained on a device GeoPyc 1360 are higher than “standard” values that can be attributed to pseudoliquid environment thus used, whereas the values of real density obtained on AccuPyc 1340 are below standard which can be attributed to closed pores present in the specimen in case of non-destructive analysis. The divergence decreases as the degree of sample fragmentation increases.

Three physical models of crack growth in condition of corrosion fatigue failure of steels are developed: energy model; model of hydrogen embrittlement, and a model of local anodic dissolution of metal at the crack tip. Anodic dissolution model appeared most preferable for quantitative analysis and provided good agreement of the variants calculation with experimental results. A predominant role of the local anodic dissolution as the main mechanism activating the process of fatigue failure of middle-strength carbon and low alloyed steels in aqueous corrosive media is demonstrated.

A design and algorithm of using certified multi-function education and research training bench are presented. The design of the bench provides simulation of a wide range of conventionally monitored items (vessels, pipelines, tubular furnaces, tanks, etc.) and main sources of acoustic emission (AE): cracks, leaks, corrosion damage induced by aggressive media, etc. AE simulator devices (AESD) are mounted on the bench via waveguides which provides acoustic communication and safety of the key elements even upon damage of the simulator. AESD are controlled using a loading device which provides setting of the onset and rate of AESD destruction. Design features of the bench also provide a possibility ofrepetitive simulation of a variety of situations that arise in-service and upon technical diagnostics of dangerous industrial objects at minimum costs. The bench can be used in research, training, certification of AE techniques and equipment, and nondestructive laboratory testing.

The methodology of accelerated tests of materials for wear in a pair of the disc-plane and the disk-to-disk is considered. A distinctive feature of the proposed method of testing is the constancy of the contact area of the elements in the friction zone. A design of a portable installation developed to implement considered testing methodology is described. The results of comparative tests of steel samples with different carbon content hardened by electromechanical treatment for wear are presented. It is shown that the results of testing for wear resistance obtained according to the proposed procedure match with the data of standard testing method, the difference being no more than 9%. The duration of each sample testing is reduced ten times.

The goal ofmathematical statistics is development ofthe methods for data analysis aimed at solution of applied problems. Approaches to developing methods of data analysis change as time goes by. Hundred years ago it was assumed that distributions ofthe data are of a certain type, for example, normal distributions, and developed statistical theory on proceeding from that assumption. Limit theorems guided theoretical studies at the next stage. A term of “small sample” suggests a sample for which the conclusions based on the limit theorems can not be used. In each statistical problem there is a need to divide the final sample sizes into two classes - those for which you can apply the limit theorems, and those for which limit theorems can not be used because of the risk of incorrect conclusions. The Monte Carlo method is often used solve those problems. More complex problems arise when the properties of statistical procedures of data analysis are affected with various deviations from original assumptions. The Monte Carlo method also can be used to study those impacts. The basic - and not solved in a general way - problem of the studying the stability of conclusions in the presence of deviations from the parametric families of distributions is the problem of choosing some distributions to be used in modeling. We consider some examples of application of the Monte Carlo method relating to the activities of our research team and formulate the main unsolved problems.

The goals of improving the efficiency of Monte Carlo calculations are considered. The key role is assigned to selection of a body of statistical tests (simulated random numbers) and to the quality of random number generators. Problems of implementation of the Monte Carlo algorithms attributed to the goal of increasing rate of convergence of asymptotic solutions to the true solutions are discussed.