STUDY OF GROUND PORK THAWING DYNAMICS USING MAGNETIC RESONANCE IMAGING

Visualization of changes in shape and size of the frozen residue during the thawing of ground pork is implemented using magnetic resonance imaging. A technique has been developed to study the displacement of thawing front line without damage to integrity of the object being thawed. It has been established that the melting of bound water crystals outran the melting of free water crystals in meat. A mathematical model that adequately describes the experimental data obtained in the analysis of tomograms is proposed. Tomograms are an important information source for studying the patterns of heat and mass transfer during the thawing of frozen foods.Visualization of changes in shape and size of the frozen residue during the thawing of ground pork is implemented using magnetic resonance imaging. A technique has been developed to study the displacement of thawing front line without damage to integrity of the object being thawed. It has been established that the melting of bound water crystals outran the melting of free water crystals in meat. A mathematical model that adequately describes the experimental data obtained in the analysis of tomograms is proposed. Tomograms are an important information source for studying the patterns of heat and mass transfer during the thawing of frozen foods

Computation of Invariants of Lie Algebras by Means of Moving Frames

A new purely algebraic algorithm is presented for computation of invariants (generalized Casimir operators) of Lie algebras. It uses the Cartan's method of moving frames and the knowledge of the group of inner automorphisms of each Lie algebra. The algorithm is applied, in particular, to computation of invariants of real low-dimensional Lie algebras. A number of examples are calculated to illustrate its effectiveness and to make a comparison with the same cases in the literature. Bases of invariants of the real solvable Lie algebras up to dimension five, the real six-dimensional nilpotent Lie algebras and the real six-dimensional solvable Lie algebras with four-dimensional nilradicals are newly calculated and listed in tables.Comment: 17 pages, extended versio

Realizations of Real Low-Dimensional Lie Algebras

Using a new powerful technique based on the notion of megaideal, we construct a complete set of inequivalent realizations of real Lie algebras of dimension no greater than four in vector fields on a space of an arbitrary (finite) number of variables. Our classification amends and essentially generalizes earlier works on the subject. Known results on classification of low-dimensional real Lie algebras, their automorphisms, differentiations, ideals, subalgebras and realizations are reviewed.Comment: LaTeX2e, 39 pages. Essentially exetended version. Misprints in Appendix are correcte

Terahertz plasma wave localization and velocity control in tapered double-layer graphene heterostructure

Terahertz plasma wave (plasmon) localization and velocity control in tapered heterostructure (taper) with double-layer graphene were numerically studied. We employ a simple rigorous theoretical model to find out the plasmon localization length and energy velocity values along the tapered structure. It is shown that the plasmon decelerates while moving from the taper apex and the deceleration process is accompanied with increase of the plasmon wave localization. While moving along the structure from the taper apex, the plasmon energy velocity as well as the plasmon localization length can become nearly an order of magnitude smaller as compared to the values near the taper apex

STUDY OF GROUND PORK THAWING DYNAMICS USING MAGNETIC RESONANCE IMAGING

Visualization of changes in shape and size of the frozen residue during the thawing of ground pork is implemented using magnetic resonance imaging. A technique has been developed to study the displacement of thawing front line without damage to integrity of the object being thawed. It has been established that the melting of bound water crystals outran the melting of free water crystals in meat. A mathematical model that adequately describes the experimental data obtained in the analysis of tomograms is proposed. Tomograms are an important information source for studying the patterns of heat and mass transfer during the thawing of frozen foods

Nuclear magnetic resonance study of ice-based composite materials reinforced with nanodisperse aluminum oxide fibers

Pulsed-field gradient NMR spectroscopy and magnetic resonance imaging methods were used to investigate water suspensions of nanosized fibers of aluminum oxide and ice composite materials based on these fibers. Introduction of the nanofibers was shown to have no noticeable structural effect in the suspensions in the Al2O3 concentration range of 1-10 wt %. High content of the filler was found to change the morphology and texture of the ice matrix in the composites remarkably: it becomes more homogeneous and acquires a higher degree of continuity; the melting front does not visualize internal melting zones or integrity defects in the composite. At the same time, addition of the nanofibers to the ice composites weakly influences the quantitative dynamics of the heat transfer, which is manifested in close values of the propagation speeds of the freezing/melting front in the samples at similar temperatures

Optical properties of parietal peritoneum in the spectral range 350- 2500 nm

ABSTRACT The wide application of optical methods in the areas of diagnostics, therapy and surgery of modern medicine has stimulated the investigation of optical properties of various biological tissues. Numerous investigations related to determination of tissue optical properties are available; however, the optical properties of many tissues have not been studied in a wide wavelength range. In this work the optical properties of parietal peritoneum in the wavelength range 350-2500 nm were measured. Measurement of the diffuse reflectance, total and collimated transmittance were performed using LAMBDA 950 (Perkin Elmer, USA) spectrophotometer with an integrating sphere, and values of absorption and scattering coefficients, and the scattering anisotropy factor were calculated by inverse Monte Carlo Method