Poisson Ratio of TiNi Muslov, S. A.; Lotkov, A. I.; Timkin, V. N.
Inorganic materials : applied research,
04/2022, Letnik:
13, Številka:
2
Journal Article
Recenzirano
A review of the published data and methods for calculating the Poisson ratio of the TiNi intermetallic compound in the poly- and single-crystal state is performed. The results of our own research are ...also presented. Significant variability of the presented data is noted, which is due to differences in the thermomechanical processing of the alloys and the measurement and calculation methods used. By averaging the matrices of elastic constants and compliance coefficients using the Voigt, Reuss, and Hill approximations, we obtained the values of the parameters of the effective elastic properties of TiNi polycrystals and calculated the Poisson ratio. Using analytical expressions to calculate the values of the extreme values, the extrema of the Poisson ratio of cubic TiNi crystals are determined for standard orientations. On the basis of a number of data, TiNi crystals are auxetics (materials having negative Poisson ratio values); on the basis of other data, they are not. We found that TiNi crystals belong to the so-called partial auxetics; in this case, the signs of the inequalities (
s
12
< 0,
s
=
s
11
+
s
12
–
s
44
/2 > 0 or
s
12
> 0,
s
=
s
11
+
s
12
–
s
44
/2 < 0) are opposite. The values of the Poisson ratio TiNi averaged over the transverse directions of deformation are analyzed. Isosurfaces of the Poisson ratio and their sections are presented using the ELATE computer graphics package and the M-ATHCAD computer algebra program. Aspects of TiNi elastic anisotropy, its parameters, and their relationship to martensitic transformations in TiNi and alloys based on it are discussed.
Link for citation: Amin Karimi Kalvarzi, Aref Shirazi, Adel Shirazy, Amin Beiranvand Pour, Ardeshir Hezarkhani, Hamed Nazerian, Timkin T.V., . Voroshilov V.G. Separation of magnetic anomalies using ...fractal method in the Esfordi region for iron exploration, central east of Iran. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 3, рр. 197-209. In Rus.
The relevance of research is determined by the possibilities of measuring the potential magnetic field, which has self-similar (fractal) properties, as well as a practical tool for prospecting and exploration of iron ores. In the Esfordi area, this method was used by us for the first time to identify, separate and interpret geophysical (magnetic) anomalies. The main aim of this thematic and practical study is the qualitative interpretation of geophysical data, the application of new methods in the prospecting and exploration of mineral deposits, modeling the geological environment and forecasting new promising areas. Object: Esfordi region, Yazd province, Iran. Methods. To obtain additional information about the subsurface, magnetometric data were used with their interpretation by the RTP (reduction to the north magnetic pole) method. For modeling purposes, an artificial sample was made, consisting of a sphere, a cube and a cuboid, and it was found that the fractal method can be used to separate anomalies for unipolar models (cube and cuboid). Results. The results of the study were applied to the Esfordi region, where it was found that at a survey scale of 1:100000, there is a direct relationship between the fractal method and the 3D model, which can be used to locate iron ore mineralization.
The paper reports the results of geological, geochemical, and isotope–geochronological studies of subvolcanic rhyolites of NW Gorny Altai and Rudny Altai, which belong to the large Hercynian volcanic ...systems: Altai-Minusa and Altai–Salair, respectively. U–Pb zircon dating revealed two age groups: ~410–405 and 390–381 Ma. The isotope–geochemical characteristics of the rhyolites demonstrate high ε
Nd
(
Т
) from +2.6 to 6.0 with relatively young model ages
T
(DM) = 851–966 Ma in Rudny Altai and older model ages, up to 1266 Ma, in NW Gorny Altai. The rhyolites show transitional geochemical signatures between within-plate and island-arc felsic magmas. The results obtained are consistent with two-stage evolution of volcanism and its migration from the continent to the ocean.
Relevance. The problem of studying organometallic compounds in carbonized and carbonaceous substances is a part of the global problem of the structure of natural materials from plant remains and ...manifestation of ore genesis in organic sedimentary deposits. This problem covers a number of issues. The most pressing one among them is the form of occurrence of finely dispersed gold in the form of organometallic compounds in metal-bearing coals and shales. This is especially true for large gold deposits of black shale strata. Aim. To study the relationship between sedimentation of organic formations and ore genesis in black shale deposits using the example of the Verninskoe deposit (Patom Highlands, Irkutsk Region). Using the SKAUFV hardware and software complex together with ICP-MS and INAA methods, which allow one to assess the degree of Au concentration in organic matter, to substantiate the possibility of determining organometallic compounds of gold that are significant in the processes of sedimentogenesis, lithogenesis and epigenesis. Methods. IR spectroscopy, instrumental neutron activation analysis (INAA) and inductively coupled plasma mass spectrometry (ICP-MS). Results. The authors have determined that the SKAUFV hardware and software complex, together with the ICP-MS and INAA methods, makes it possible to establish the role of organic matter in metasomatism and to identify temperature zonality and the associated gold concentrationin the ore zone. To determine the organometallic compounds of Au, structural and genetic indicators (Pm, Ko, PVt+L, PI) were selected. These indicators reflect the significance of sedimentation, diagenesis, catagenesis and epigenesis on Au concentration in organic matter. These indicators made it possible to assess the level of temperature impact on sedimentary deposits of regional metamorphism and near-ore metasomatism. In this regard, subzones of Au concentration were established in the ore zone, determined by temperature zoning in the form of a manifestation of local metasomatism. The latter was influenced by the protein-fat composition of plants that form organic matter.
Link for citation: Voroshilov V.G., Molukpaeva D.K., Timkin T.V., Savinova O.V. Genesis and mineral-geochemical zoning of the quartz-vein gold deposit Central (Kuznetsk Alatau). Bulletin of the Tomsk ...Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 9, рр. 7-17. In Rus.
Relevance. The peculiarity of the Central ore field consists in the fact that gold mineralization is entirely localized within the initially homogeneous granitoid massif, therefore, the identified mineral-geochemical zoning is almost entirely caused by superimposed post-magmatic processes. The ore-metasomatic zoning is extremely contrasting and is fixed by various methods, both traditional and the most modern. This creates a unique opportunity to refine and improve the model of formation of gold mineralization, which is widely manifested in the Altai-Sayan folded region, associated with the formation of granitoid massifs of «variegated composition». The purpose of the research is to study postmagmatic hydrothermal-metasomatic processes and the zoning of their location in the Central gold field (Kuznetsk Alatau); substantiate the genetic model of the formation of gold mineralization in the ore field. Objects: granitoids, metasomatites and ores of the Central ore field (Kuznetsk Alatau). Methods: detailed mineralogical and geochemical mapping, optical and electron microscopy, microprobe analysis, study of the typomorphic properties of minerals. Results. The products of postmagmatic hydrothermal activity mapped by the authors are combined into four formations that replace each other in time and space: 1) albite-amphibole metasomatites; 2) quartz-K-feldspar-biotite metasomatites; 3) epidote-chlorite propylites; 4) beresites with conjugated quartz-gold-sulfide veins. The earliest albite-amphibole metasomatites are confined to the bottom part of the granitoid massif and higher along the section (and from south to north) are replaced first by quartz-K-feldspar-biotite metasomatites, and then by epidote-chlorite propylites. Near-vein beresites are superimposed on all previous metasomatites. At the same time, in the zone of development of albite-amphibole metasomatites, beresites have a quartz-muscovite composition, and ores are represented by low-sulfide quartz veins. From south to north (and from bottom to top), quartz-muscovite beresites are replaced by quartz-carbonate-sericite ones, and the sulfide content of the veins consistently increases up to 50–80 %. A model is proposed for the formation of multi-tiered gold mineralization with the determining ore-controlling role of the Kuznetsk-Altai deep fault.
Here, using data from the NEMO-3 experiment, we have measured the two-neutrino double beta decay (2νββ) half-life of 82Se as T2ν1/2=9.39±0.17( stat )±0.58( syst )×1019 y under the single-state ...dominance hypothesis for this nuclear transition.
The superelasticity and shape memory effects upon torsional straining of samples of the binary titanium nickelide based alloy with the
B
19' martensitic phase structure have been investigated. It has ...been found that, in samples plastically strained during their loading up to a specified torsional strain of ~39%, the superelasticity value can attain 6.3%, which is comparable with the classical superelasticity effect. The superelasticity manifestation in the martensitic state upon torsion straining of the samples has been compared with the results of similar studies on tensile straining of the titanium nickelide-based alloy samples.
Link for citation: Adel Shirazy, Ardeshir Hezarkhani, Aref Shirazi, Timkin T.V., Voroshilov V.G. Geophysical explorations by resistivity and induced polarization methods for the copper deposit, South ...Khorasan, Iran. Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2022, vol. 333, no. 3, рр. 99-110. In Rus
The relevance. These are the first geophysics studies in the Mesgaran exploration area. Based on geological studies in the mineral zone, copper mineralization was proven. The mineralization type in this area was identified as Cyprus-type massive sulfide. The complexity of the geological structure determines the need to use geophysical research and forecasting methods for planning mining and drilling operations. The main aim of this study is the application of geophysical methods in the search for mineral deposits and modeling of the geological environment. Object: Mesgaran exploration area, South Khorasan province, Iran. Methods. In order to obtain more subsurface information, geophysical methods IP and Rs were used. Five profiles were designed and implemented for geoelectric surveys. Overall, five profiles (P1 to P5) were read as dipole-dipole arrays with 784 points. The profiles were taken east-west and north-south along parallel to the mineralization zones. The dipole-dipole array is designed with the parameters AB=MN=20 m, jump=20 m and up to 6 jumps for MN. Results. In general, four types of anomalies were identified in these investigations. Which to some extent revealed the association of anomalies with the types of rocks and mineralization of the study area: 1) anomalies with low electrical resistivity, as well as low polarity, often correspond to quaternary alluvial deposits; 2) abnormalities with high electrical resistance, and low polarity, which are consistent with limestone’s and are often superficial; 3) anomalies with high polarity and high resistance, which in the south of the profiles form altitude and correspond to the agglomerates; 4) anomalies with high polarity and higher relative resistance are associated with igneous masses, which are often composed of andesitic-basaltic rocks. Based on the position of the identified anomalies in the 5 profiles, the optimal location of the drills was determined.
The present work is devoted to solving the tasks aimed at the study of pressure-driven membrane processes used in the manufacture of ultrafiltration cottage cheese via microfiltration followed by ...ultrafiltration using membranes of domestic manufacture. As a result of this study, the technological parameters of baromembrane processes (speed of solution over the membrane, operating pressure, and temperature) providing the maximum productivity and selectivity of the microbiological clearance of skim milk by microfiltration and the ultrafiltration concentration of curd have been determined. The possibility of affecting the characteristics (permeability and selectivity) of the ultrafiltration process by approaching the isoelectric point of the protein fraction due to the change in the active acidity of the curd under concentration has been considered. The applicability of the microfiltration process in cottage cheese making has been confirmed, since it leads to enhancement of the performance of ultrafiltration membranes and increases the shelf life of the resulting product.
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