49 research outputs found
METHODS OF IDENTIFICATION OF MUSCLE TISSUE IN MEAT PRODUCTS. PREREQUISITES FOR CREATING A MULTI–LEVEL CONTROL SYSTEM
Unfair production and products that do not comply with the declared labeling are currently an acute problem in the field of technical regulation, including with regard to food safety and quality. Given the high added value and multicomponent composition, finished meat products are among the most susceptible to adulteration. Despite the best efforts of regulatory agencies to counteract these inconsistencies, the hidden substitution of cheaper or lower-grade meats is still widespread. One of the main tasks facing research laboratories and testing centers today is the detection of falsification of food products, as well as standardization and certification of techniques necessary to solve such problems. The manufacturer, aware of the current control methods, can go to the deception, using vegetable protein, new unregistered feed additives. To determine the complex changes that occur in products, it is necessary to use methodological approaches in which it is possible to reliably determine these changes. The paper presents an overview of the most commonly used methodologies for assessing the component composition of meat products. Quality assessment of meat products includes control of components of finished products. The most difficult task is to determine the proportion of muscle protein in multicomponent meat products that have undergone heat treatment.Unfair production and products that do not comply with the declared labeling are currently an acute problem in the field of technical regulation, including with regard to food safety and quality. Given the high added value and multicomponent composition, finished meat products are among the most susceptible to adulteration. Despite the best efforts of regulatory agencies to counteract these inconsistencies, the hidden substitution of cheaper or lower-grade meats is still widespread. One of the main tasks facing research laboratories and testing centers today is the detection of falsification of food products, as well as standardization and certification of techniques necessary to solve such problems. The manufacturer, aware of the current control methods, can go to the deception, using vegetable protein, new unregistered feed additives. To determine the complex changes that occur in products, it is necessary to use methodological approaches in which it is possible to reliably determine these changes. The paper presents an overview of the most commonly used methodologies for assessing the component composition of meat products. Quality assessment of meat products includes control of components of finished products. The most difficult task is to determine the proportion of muscle protein in multicomponent meat products that have undergone heat treatment
Protonation and Photocatalytic Activity of the Rb 2
The Rb2La2Ti3O10 layered oxide was synthesized by the solid-state method. Three phases with different protonation degrees and intercalated water contents were obtained from the initial compound by the treatment with distilled water and hydrochloric acid. The obtained samples were characterized by powder X-ray diffraction, SEM, X-ray microanalysis, BET, DRS, and TG. It was found that the complete ion exchange of Rb+ for H+ in the layered oxide Rb2La2Ti3O10 proceeds through the formation of two metastable intermediate phases with average protonation degrees of 0.5 and 0.75, which successively transform from one to another. Each of these phase transformations is accompanied not only by the contraction of the interlayer distance but also by the displacement of adjacent perovskite layers by 1/2 of the cell parameter which results in the change in the space group. The photocatalytic activity of obtained samples decreases with the increase in the protonation degree, which correlates with the decrease in the intercalated water content
Biases in estimation of insect herbivory from herbarium specimens
Information regarding plant damage by insects in the past is essential to explore impacts of climate change on herbivory. We asked whether insect herbivory measured from herbarium specimens reflects the levels of herbivory occurring in nature at the time of herbarium sampling. We compared herbivory measurements between herbarium specimens collected by botany students and ecological samples collected simultaneously by the authors by a method that minimized unconscious biases, and asked herbarium curators to select one of two plant specimens, which differed in leaf damage, for their collections. Both collectors and curators generally preferred specimens with lesser leaf damage, but the strength of this preference varied among persons. In addition, the differences in measured leaf damage between ecological samples and herbarium specimens varied among plant species and increased with the increase in field herbivory. Consequently, leaf damage in herbarium specimens did not correlate with the actual level of herbivory. We conclude that studies of herbarium specimens produce biased information on past levels of herbivory, because leaf damage measured from herbarium specimens not only underestimates field herbivory, but it is not proportional to the level of damage occurring in nature due to multiple factors that cannot be controlled in data analysis
Riociguat treatment in patients with chronic thromboembolic pulmonary hypertension: Final safety data from the EXPERT registry
Objective: The soluble guanylate cyclase stimulator riociguat is approved for the treatment of adult patients with pulmonary arterial hypertension (PAH) and inoperable or persistent/recurrent chronic thromboembolic pulmonary hypertension (CTEPH) following Phase
Highly Efficient Liquid-Phase Exfoliation of Layered Perovskite-like Titanates HLnTiO<sub>4</sub> and H<sub>2</sub>Ln<sub>2</sub>Ti<sub>3</sub>O<sub>10</sub> (Ln = La, Nd) into Nanosheets
Nanosheets of layered perovskite-like oxides attract researchers as building blocks for the creation of a wide range of demanded nanomaterials. However, Ruddlesden–Popper phases are difficult to separate into nanosheets quantitatively via the conventional liquid-phase exfoliation procedure in aqueous solutions of bulky organic bases. The present study has considered systematically a relatively novel and efficient approach to a high-yield preparation of concentrated suspensions of perovskite nanosheets. For this, the Ruddlesden–Popper titanates HLnTiO4 and H2Ln2Ti3O10 (Ln = La, Nd) have been intercalated by n-alkylamines with various chain lengths, exposed to sonication in aqueous tetrabutylammonium hydroxide (TBAOH) and centrifuged to separate the nanosheet-containing supernatant. The experiments included variations of a wide range of conditions, which allowed for the achievement of impressive nanosheet concentrations in suspensions up to 2.1 g/L and yields up to 95%. The latter were found to strongly depend on the length of intercalated n-alkylamines. Despite the less expanded interlayer space, the titanates modified with short-chain amines demonstrated a much higher completeness of liquid-phase exfoliation as compared to those with long-chain ones. It was also shown that the exfoliation efficiency depends more on the sample stirring time in the TBAOH solution than on the sonication duration. Analysis of the titanate nanosheets obtained by means of dynamic light scattering, electron and atomic force microscopy revealed their lateral sizes of 30–250 nm and thickness of 2–4 nm. The investigated exfoliation strategy appears to be convenient for the high-yield production of perovskite nanosheet-based materials for photocatalytic hydrogen production, environmental remediation and other applications
The effect of transition metal substitution in the perovskite-type oxides on the physicochemical properties and the catalytic performance in diesel soot oxidation
The paper is focused on the Fe for Co substitution effect on the redox and catalytic properties in the perovskite structure of GdFeO3. The solid oxides with the composition GdFe1xCoxO3 (x = 0; 0.2; 0.5; 0.8; 1) were obtained by the sol-gel method and characterized by various methods: Xray diffraction (XRD), temperature-programmed reduction (H2-TPR), N2 sorption, temperatureprogrammed desorption of oxygen (TPD-O2), simultaneous thermal analysis (STA), and X-ray photoelectron spectroscopy (XPS). The H2-TPR results showed that an increase in the cobalt content in the GdFe1xCoxO3 (x = 0; 0.2; 0.5; 0.8; 1) leads to a decrease in the reduction temperature. Using the TPD-O2 and STA methods, the lattice oxygen mobility is increasing in the course of the substitution of Fe for Co. Thus, the Fe substitution in the perovskite leads to an improvement in the oxygen reaction ability. Experiments on the soot oxidation reveal that catalytic oxidation ability increases in the series: GdFe0.5Co0.5O3 < GdFe0.2Co0.8O3 < GdCoO3, which is in good correlation with the increasing oxygen mobility according to H2-TPR, TPD-O2, and STA results. The soot oxidation over GdFeO3 and GdFe0.8Co0.2O3 is not in this range due to the impurities of iron oxides and higher specific surface area