Boiling of the Interface between Two Immiscible Liquids below the Bulk Boiling Temperatures of Both Components

We consider the problem of boiling of the direct contact of two immiscible liquids. An intense vapour formation at such a direct contact is possible below the bulk boiling points of both components, meaning an effective decrease of the boiling temperature of the system. Although the phenomenon is known in science and widely employed in technology, the direct contact boiling process was thoroughly studied (both experimentally and theoretically) only for the case where one of liquids is becoming heated above its bulk boiling point. On the contrary, we address the case where both liquids remain below their bulk boiling points. In this paper we construct the theoretical description of the boiling process and discuss the actualisation of the case we consider for real systems.Comment: 17 page, 7 figures, accepted to Eur. Phys. J.

Collision of viscoelastic bodies: Rigorous derivation of dissipative force

We report a new theory of dissipative forces acting between colliding viscoelastic bodies. The impact velocity is assumed not to be large, to avoid plastic deformations and fragmentation at the impact. The bodies may be of an arbitrary convex shape and of different materials. We develop a mathematically rigorous perturbation scheme to solve the continuum mechanics equation that deals with both displacement and displacement rate fields and accounts for the dissipation in the bulk of the material. The perturbative solution of this equation allows to go beyond the previously used quasi-static approximation and obtain the dissipative force. This force does not suffer from the physical inconsistencies of the latter approximation and depends on particle deformation and deformation rate.Comment: 9 pages, 1 figure. arXiv admin note: text overlap with arXiv:1410.328

Noise-Produced Patterns in Images Constructed from Magnetic Flux Leakage Data

Magnetic flux leakage measurements help identify the position, size and shape of corrosion-related defects in steel casings used to protect boreholes drilled into oil and gas reservoirs. Images constructed from magnetic flux leakage data contain patterns related to noise inherent in the method. We investigate the patterns and their scaling properties for the case of delta-correlated input noise, and consider the implications for the method's ability to resolve defects. The analytical evaluation of the noise-produced patterns is made possible by model reduction facilitated by large-scale approximation. With appropriate modification, the approach can be employed to analyze noise-produced patterns in other situations where the data of interest are not measured directly, but are related to the measured data by a complex linear transform involving integrations with respect to spatial coordinates.Comment: 11 pages, 2 figure

A dissipative force between colliding viscoelastic bodies: Rigorous approach

A collision of viscoelastic bodies is analysed within a mathematically rigorous approach. We develop a perturbation scheme to solve continuum mechanics equation, which deals simultaneously with strain and strain rate in the bulk of the bodies' material. We derive dissipative force that acts between particles and express it in terms of particles' deformation, deformation rate and material parameters. It differs noticeably from the currently used dissipative force, found within the quasi-static approximation and does not suffer from inconsistencies of this approximation. The proposed approach may be used for other continuum mechanics problems where the bulk dissipation is addressed.Comment: 6 pages, 1 figur

Magnetic Flux Leakage Method: Large-Scale Approximation

We consider the application of the magnetic flux leakage (MFL) method to the detection of defects in ferromagnetic (steel) tubulars. The problem setup corresponds to the cases where the distance from the casing and the point where the magnetic field is measured is small compared to the curvature radius of the undamaged casing and the scale of inhomogeneity of the magnetic field in the defect-free case. Mathematically this corresponds to the planar ferromagnetic layer in a uniform magnetic field oriented along this layer. Defects in the layer surface result in a strong deformation of the magnetic field, which provides opportunities for the reconstruction of the surface profile from measurements of the magnetic field. We deal with large-scale defects whose depth is small compared to their longitudinal sizes---these being typical of corrosive damage. Within the framework of large-scale approximation, analytical relations between the casing thickness profile and the measured magnetic field can be derived.Comment: 12 pages, 3 figure

Taymyr Reindeer Herding as a Branch of the Economy and a Fundamental Social Identification Practice for Indigenous Peoples of the Siberian Arctic

There are two factors affecting the way that Nenets and Dolgan people of Taymyr define their regional identity: 1) their traditional trade (reindeer herding); 2) ethnic art-making where the reindeer acts as an image and a symbol of ethnic traditions, touchstones, and values found among the indigenous peoples of Taymyr. Field research was conducted in Taymyr settlements (such as Nosok, Karaul, and Khatanga) from 2010 to 2014. The researchers interviewed Nenets and Dolgan people who belong to non-governmental organizations representing Taymyr indigenous peoples, run businesses or work in government agencies, schools, and other organizations implementing cultural policies. Indigenous peoples have very low economic and social activity. The Dolgans also have a very poor standard of living due to lack of reindeer. The Post-Soviet era has seen an income gap growing between the Dolgans and the Nenets and unequal economic groups being formed. Reviving reindeer herding is essential. Nenets and Dolgan reindeer herding is an economically inefficient subsidized branch of agriculture, but its role is symbolic rather than economic. Nenets and Dolgan reindeer herding is an ethnicity-forming and ethnicity-sustaining factor. Today’s reindustrialization of Taymyr may end up exterminating its indigenous peoples’ unique economic, environmental, and cultural practices. Taymyr’s political establishment must pay due attention to the threat of ruining these unique practices. DOI: 10.5901/mjss.2015.v6n3s5p22