The effect of Na, Ca, Mg, Al and Fe on the efficiency of sorption concentration of Ru, Pd, Ir, Pt and Au chlorocomplexes on Styrosorb-514 hypercrosslinked polystyrene is studied in the presence of tributylamine ion-pair reagent. It is shown that general saline composition of the solutions strongly affects the degree of noble metal extraction. Various matrix components of rocks (Na, Ca, Mg, Al, and Fe) have a specific and different effect on the degree of sorption and extraction of the analytes. The obtained experimental data indicate that the introduction of Fe³+ ions into a final sorption solution obtained after fusing the rock into NiS-matte and subsequent dissolution of the matte leads to an increase in the degree of Ir sorption up to 90%. Quantitative (97 ±3%) sorption of five noble metals (Ru, Pd, Ir, Pt, Au) on Stirisorb-514 is achieved by combining fusion of a solid sample into NiS-matte and introduction of Fe³⁺ ions (2 g/liter) into the sorption solution. Further simultaneous determination of noble metals is possible either in the phase of sorbent using appropriate instrumental control or in the phase of the concentrate when selecting a suitable desorbtion agent.

Composition and structure of (2R,4R,4aR,7R,8aR )-4,7-dimethyl-2- (thiophen-2-yl)octahydro-2H-chromen-4-ol are determined using elemental analysis, UV-, IR-, NMR¹H- and¹³C-spectrometry. A number of physicochemical parameters - melting point, molecular weight, “pellucidness,” “chromacity” and pH; humidity (after Fisher) and sulphated ash - are determined. A qualitative determination of the substance is based on the indophenine reaction between thiophene and isatin with sulfuric acid present. A method of quantitative determination of the active substance and validation of the procedure is developed using HPLC. Content of the active substance determined by the proposed method ranges from 99.4 to 100.7%. The detection and quantification limits are 0.78 and 2.4 μg/ml, respectively.

Ultra-high-performance liquid chromatography/quadrupole-time-of-flight mass spectrometry of high resolution is used for rapid screening and determination of seven neonicotinoid insecticides (acetamiprid, dinotefuran, imidacloprid, clotianidin, nitenpyram, thiacloprid and thiamethoxam) in natural and potable water without sample preparation. An insignificant matrix effect is observed from the components of natural water samples. Two modifications of neonicotinoid determination in water are considered: i) standard addition method and ii) calibration curve. The detection limits and determinable contents of neonicotinoids range within 0.01 -1 ng/ml and 0.04 - 50(100) ng/ml, respectively. The relative standard deviation of the analysis results did not exceed 0.1, the analysis duration was 10 - 15 min.

We describe here the main principles and parameters of the laboratory thermogasobaric unit intended for chemical dispersion of alloys and intermetallic compounds by hydrogenation/dehydrogenation and nitriding in a wide range of temperatures and working pressures of reaction gases. Case study of Sm₂F₁₇ and Nd₂Fe₁₄B - the most important materials for manufacturing high-energy permanent magnets - demonstrated the possibilities of the installation in terms of imparting the desired properties to the materials by imbedding atoms of light elements into a metal matrix. Comparative analysis of the practical results revealed that obtained magnetic materials thus obtained exhibit improved magnetic characteristics compared to those for cast alloys and powders obtained by mechanical dispersion, bypassing the stage of preliminary hydride dispersion.

The impact of the geometry (mainly the surface roughness) of cold rolled strips of anisotropic electrical (transformer) steel of domestic production (technical soft magnetic bcc alloy Fe - 3 wt.% Si with an edge crystallographic texture (110)[001]) on the magnetic properties (particularly on electromagnetic induction B₈₀₀ and specific magnetic losses P₁7/₅₀) is studied. It is shown that corrugations are formed on the surface of steel strips during cold rolling to a final thickness of 0.23 - 0.30 mm with a reduction of 50 - 70%. As a rule, their ridges and valleys are perpendicular to the direction of rolling and have a wavy form. Formation of the relief is attributed to the gradient of the stress-strain state along the cross section of the strip and to the tightness of the flow of the surface layers at the end of the deformation region and inevitably accompanies the rolling process. The presence of corrugations like any other roughness on the strip surface reduces B₈₀₀ and increases P_1,7/₅₀. We propose a method for elimination of the surface defects (including corrugations) of cold rolled steel strips after cold rolling, i.e., ironing, which can be carried out by drawing of strips with a small draft (~3%) in cold rolling mills with a disconnected work roll drive using coilers. Introduction of drawing into the transformer steel manufacture technology improves the magnetic properties of steel due to increased perfection of the crystallites (grains), increased sharpness of the edge(110)[001] texture and free movement of the boundaries of magnetic domains upon magnetic reversal. Ironing of the steel strips of nitride-copper melt (inhibitors - dispersed particles of AlN and CuMn₂O₄) with a thickness of 0.30 mm increased B₈₀₀ up to 1.93 T and decreased P_1,7/₅₀ to 1.07 W/kg (thus improving the magnetic properties by 5.7 and 10%, respectively). The resulted properties of domestic steel production are not inferior to those of foreign steel.

The polytherm of crystallization of the NH₄NO₃ - C₆H₁₂N₄ - H₂O system is first studied. The system under study has one eutectic and two eutonic systems in the terminating elements. In the eutectic system NH₄NO₃ - C₆H₁₂N₄ there is a stratification region with the presence of oxidation-reduction reactions (ORR), which is accompanied by the emission of gases confirming the redox process. Simulation procedure is used to calculate the characteristics of triple-eutonics in the system NH₄NO₃ - C₆H₁₂N₄ - H₂O providing composition and melting temperature of eutonics of the ternary system from the data regarding the terminating elements. Moreover, the solution of the inverse problem, which consists in primary determination of the characteristics of triple-eutonics, provides optimization of the choice of the internal cuts for elucidation of monovariant curves and crystallization surface of the ternary system. The use of simulation and single (confirming) experiment by differential thermal analysis (DTA) significantly reduced the time and labor costs for studying the system as a whole. A DTA unit of the new generation is used to confirm the validity of the triple-eutonics simulation and the internal sections of the system are studied using visual-polythermic analysis. The crystallization surface of the NH₄NO₃ - C₆H₁₂N₄ - H₂O system is constructed. The system has a triple eutonics with a temperature of-18°C. The area of oxidation-reduction reactions is first revealed on the crystallization field, whereas a number of specially considered internal sections made it possible to reveal the size of the region of redox reactions inside the Tamman triangle.

The article is devoted to the problematic issues regarding unification of the methods of mechanical testing of structural materials for crack resistance and activities of the Scientific and Methodological Commission for Standardization in the Fracture Mechanics of the Scientific and Technical Council of the State Standard of the USSR in connection with the 40th anniversary of its creation. The methodological foundations of tests for crack resistance are considered in connection with the types of limiting states of the materials and structures with due regard for domestic experience in the study of brittle fracture. The results of scientific and organizational activities of the Commission are presented in a historical retrospective relating to the set of goals and scientific prerequisites for developing of technical standards and regulatory documents in the field of experimental methods in fracture mechanics. An emphasis is made on the correlation and succession of the basic methodological principles of testing for crack resistance and determining the characteristics of the mechanical of materialsBrief descriptions of the conceptual and scientific base of GOST 25.506 - 85, methodological instructions and recommendations regulating determination of the fracture toughness characteristics under static, dynamic and cyclic loading, welded joints and at the stage of crack arrest are presented. Developed regulatory and technical documentation formed the base of the regulatory guidelines for methodological documents regarding testing of various construction materials, conditions of crack development, types of loading and extreme states of materials and impacts. Preparation and publication of the All Union State standard (GOST) predetermined the positive result of the initial stage of formation and further fruitful development of combined experimental and computational methods of fracture mechanics.

Results of the activities of the Scientific and Methodological Commission for Standardization in the field of Fracture Mechanics of the Scientific and Technical Council of the State Standard of the USSR in connection with the 40th anniversary of its creation are presented. An emphasis is made on the results of the basic experiment in fracture mechanics in order to verify the main methodological guidelines of tests for crack resistance. A number of problematic issues and limitations arising upon testing and interpretation of the results, especially when using plastic steels and inherent strive to extend ideas and requirements of linear fracture mechanics to elastoplastic strain and fracture. The list of methodological recommendations for determining the characteristics of crack resistance for specific classes of materials and test conditions with reference to specific objects and structures previously developed by the commission and published in the late 1990s is presented. The substantial part of the methodological recommendations regulating the general approaches to carrying out calculations for crack resistance with a description of the flowchart calculations based on the criteria of fracture mechanics is given in more details. Areas of application of force, energy and deformation criteria of fracture are determined, as well as existing assurance coefficients and their allowed values are specified. The main trends and directions of the development of computational and experimental methods of fracture mechanics are considered in conclusion along with the primary goals of unification of test and computation methods used for determination of the crack resistance.

Results of x-ray fluorescence analysis of several organic manganese compounds are used to study and elucidate the sources of errors in a non-destructive technique of analysis by the method of external standard with dilution accepted in practice of elemental analysis at the Institute of Organoelement Compounds of the Russian Academy of Sciences. Metrological differences occurred when using emulsion polystyrene and chromatographic cellulose as diluents are discussed.

The main aspects of the efficiency of rapid determination of the sand quality indicators are discusses along with analysis of the methods used for assessing individual quality indicators of highly-silicate raw materials. Basic approaches to determination of the significance of individual quality indicators are considered and quality indicators of the quartz sand significant for the glass ware production are revealed. A geometric model of the integrated index of the quartz sand quality is developed.