TRENDS FOR THE DEVELOPMENT OF THE TECHNOLOGIES FOR SEMI-FINISHED RESTRUCTURED MEAT PRODUCTS

The authors analyze the main trends in the technology of restructured meat products. The main technical and technological methods of restructured meat production technologies are identified. An innovative idea for a new product – restructured semi-finished meat products, is formulated; the main indicators are defined and characterized. Criteria for the selection of food ingredients and mixtures based on them, which are able to modify adhesive and cohesive properties of meat pieces for obtaining a new product - restructured meat products.

Effects of Zn and Mg Segregations on the Grain Boundary Sliding and Cohesion in Al: Ab Initio Modeling

The formation of Zn and Mg segregations at a tilt Σ5{013} <100> grain boundary (GB) in Al and the effects of these solutes on deformation behavior of polycrystalline Al were investigated using ab initio total energy calculations. Using a step-by-step modeling of the segregation process, we found that the formation of a thick segregation layer of Zn at the GB is energetically preferable, while the formation of an atomically thin segregation layer is expected in the case of Mg. To reveal the effect of segregation on the cohesive properties of Al GBs, we calculated the energy of cleavage decohesion and the shear resistance for GB sliding. We show that the segregation of Zn results in a substantial decrease in barriers for GB sliding, while the segregation of Mg increases the barriers. The results obtained allow us to explain experimental findings and demonstrate a strong relationship between chemical bonding of solute atoms, their segregation ability, and GB strength.

On Quantitative Assessment of Effective Cement Bonding to Guarantee Wellbore Integrity

Methane leakage due to compromised wellbore cement integrity may result in operational complications and environmental contaminations in oil and gas wells. In this work, the problem of fluid-driven fracture propagation at the cement interfaces is revisited by a thorough and comprehensive consideration of the non-uniform cement bonding to the formation along the wellbore. While previous works were mainly focused on discharge without attention to mechanical failure or mechanical failure without ties to seepage rate, here we couple these two analyses to provide a practical aspect of this approach. As revealed by cement evaluation logs, the quality of the cement behind the casing varies and may include flaws in the form of channels or pockets of mud residuals. A novel methodology, initiated with laboratory-scale cement bonding properties using the push-out test, is introduced to estimate the cohesive properties of the cement interface, considering mud removal and mud residuals in the rock. Then the measured cohesive properties are applied to a field-scale numerical model with an embedded cohesive layer between cement and formation to evaluate the susceptibility of the wellbore to develop cement debonding. The excessive fluid pressure at the casing shoe is assumed to be the source for the fracture initiation. The proposed numerical model has been tested against actual SCP field tests for validation purposes. This model may estimate the geometry of leakage pathways and predict leakage flow rate within acceptable ranges. The effect of several key factors in the development of SCP due to the cement debonding is investigated. The results show that the early stage of SCP build up is controlled by the cohesive properties of the cement interfaces (i.e., cement properties), but the cohesive properties have minor effects on the stabilized pressure. The method proposed herein presents a method to evaluate the cement bond quantitatively to be further integrated in cement design.

Evaluation of the Cohesive Properties of SBS-Modified Binders at Low Temperatures

The durability, fatigue resistance, and low-temperature behavior of asphalt layers are greatly affected by the properties of bitumen. Therefore, the composition of bitumen is frequently modified to improve the performance of asphalt mixtures. Sty-rene-butadiene-styrene (SBS) has been the most often used additive recently. Researchers are trying to improve the cohesive and adhesive properties of binders by such polymer-based additives. In this study, 160/220 penetration grade bitumen and Kraton D 1101 SBS were used. The present study contains a new evaluation for determining the cohesive behavior of SBS-modified binders at -1°C, -3°C, and -5°C. The results of this evaluation were compared to conventional and rheological test results. Penetration, softening point, viscosity, dynamic shear rheometer, and bending beam rheometer tests were therefore conducted. Finally, the results of a low-temperature tensile test were found to be consistent with the results of the other tests; hence, they also confirm the cohesive behavior of SBS-modified binders at low temperatures.