Розробка методики оцінювання напружено-деформованого стану позацентрово розтягнутих трубобетонних елементів

We developed a procedure for the evaluation of the stressed-deformed state of pipe-concrete elements that are stretched off-center with an entire cross-section. The obtained functional dependences make it possible to establish the magnitudes of stresses and strains in the pipe-shell and the concrete of pipe-concrete elements that are stretched off-center depending on geometrical characteristics and physical-mechanical properties of the element materials.The procedure takes into account the elastic stage of work of the materials considering the volumetric-stressed state and an increase in the loading from zero to destruction. The advantage of the developed procedure is the proposed simplified method for solving the system of defining equations based on the hypothesis about a joint work of the components of pipe-concrete (steel shell and concrete core) at all stages of loading with an off-center stretching effort. This procedure is implemented by consistently solving separate equations. The developed procedure for the evaluation of the stressed-deformed state of stretched pipe-concrete elements takes into account the negative impact of a bending moment, which is an additional force factor under conditions of the off-center stretching. Analysis of the comparison results of experimental data with those theoretical, obtained by the given procedure, confirms the hypothesis about joint work of the steel shell and the concrete core up until the moment when a pipe-concrete element that is stretched off-center runs out of its bearing capacity.The proposed procedure for the evaluation of the stressed-deformed state makes it possible with a sufficient accuracy to determine the bearing capacity of pipe-concrete elements that are stretched off-center with different geometrical parameters and mechanical properties. Results of the study could be applied when designing the structures by determining the bearing capacity of pipe-concrete elements exposed to stretching.Разработана методика оценки напряженно-деформированного состояния внецентренно растянутых трубобетонных элементов сплошного поперечного сечения. Получены теоретические зависимости. Определены значения напряжений і деформаций в оболочке и бетонном ядре в зависимости от геометрических характеристик и физико-механических свойств материалов. Учитывается объемно-напряженное состояние бетонного ядраРозроблено методику оцінки напружено-деформованого стану позацентрово розтягнутих трубобетонних елементів суцільного поперечного перерізу. Отримано теоретичні залежності. Визначено значення напружень і деформацій в оболонці та бетонному ядрі залежно від геометричних характеристик і фізико-механічних властивостей матеріалів. Ураховується об’ємно-напружений стан бетонного осерд

Real-time quantification of meat paste constituents displaying nonlinear blending behavior including salt using an in-line NIR MEMS sensor

Rapid and robust quality monitoring of the composition of meat pastes is of fundamental importance in processing meat and sausage products. Here, an in-line near-infrared spectroscopy/micro-electro-mechanical-system-(MEMS)-based approach, combined with multivariate data analysis, was used for measuring the constituents fat, protein, water, and salt in meat pastes within a typical range of meat paste recipes. The meat pastes were spectroscopically characterized in-line with a novel process analyzer prototype. By integrating salt content in the calibration set, robust predictive PLSR models of high accuracy (R2 > 0.81) were obtained that take interfering matrix effects of the minor and NIR-inactive meat paste recipe component “salt” into account as well. The nonlinear blending behavior of salt concentration on the spectral features of meat pastes is discussed based on a designed mixture experiment with four systematically varied components

Process validation and a new method for quality control of ultrathin polyelectrolyte multilayer coatings

The properties of polyelectrolyte multilayers are ruled by the process parameters employed during self-assembly. This is the first study in which a design of experiment approach was used to validate and control the production of ultrathin polyelectrolyte multilayer coatings by identifying the ranges of critical process parameters (polyelectrolyte concentration, ionic strength and pH) within which coatings with reproducible properties (thickness, refractive index and hydrophilicity) are created. Mathematical models describing the combined impact of key process parameters on coatings properties were developed demonstrating that only ionic strength and pH affect the coatings thickness, but not polyelectrolyte concentration. While the electrolyte concentration had a linear effect, the pH contribution was described by a quadratic polynomial. A significant contribution of this study is the development of a new approach to estimate the thickness of polyelectrolyte multilayer nanofilms by quantitative rhodamine B staining, which might be useful in all cases when ellipsometry is not feasible due to the shape complexity or small size of the coated substrate. The novel approach proposed here overcomes the limitations of known methods as it offers a low spatial sampling size and the ability to analyse a wide area without restrictions on the chemical composition and shape of the substrate

Development of a Procedure for the Evaluation of the Stressed-deformed State of Pipe-concrete Elements That Are Stretched Off-center

We developed a procedure for the evaluation of the stressed-deformed state of pipe-concrete elements that are stretched off-center with an entire cross-section. The obtained functional dependences make it possible to establish the magnitudes of stresses and strains in the pipe-shell and the concrete of pipe-concrete elements that are stretched off-center depending on geometrical characteristics and physical-mechanical properties of the element materials.The procedure takes into account the elastic stage of work of the materials considering the volumetric-stressed state and an increase in the loading from zero to destruction. The advantage of the developed procedure is the proposed simplified method for solving the system of defining equations based on the hypothesis about a joint work of the components of pipe-concrete (steel shell and concrete core) at all stages of loading with an off-center stretching effort. This procedure is implemented by consistently solving separate equations. The developed procedure for the evaluation of the stressed-deformed state of stretched pipe-concrete elements takes into account the negative impact of a bending moment, which is an additional force factor under conditions of the off-center stretching. Analysis of the comparison results of experimental data with those theoretical, obtained by the given procedure, confirms the hypothesis about joint work of the steel shell and the concrete core up until the moment when a pipe-concrete element that is stretched off-center runs out of its bearing capacity.The proposed procedure for the evaluation of the stressed-deformed state makes it possible with a sufficient accuracy to determine the bearing capacity of pipe-concrete elements that are stretched off-center with different geometrical parameters and mechanical properties. Results of the study could be applied when designing the structures by determining the bearing capacity of pipe-concrete elements exposed to stretching