MODELLING CONVECTIVE THIN-LAYER DRYING OF CARROT SLICES AND QUALITY PARAMETERS

The influence of thin layer convective dehydration parameters on drying kinetics parameters, chemical composition, and color parameters of carrot slices were investigated, and corresponding mathematical models were developed. In the carrot slices, convective dehydration process hot air temperature and the sample slice thickness were varied, while measured, calculated, and modeled responses were: time of dehydration, effective moisture diffusivity, the energy of activation, proteins and cellulose contents, lightness, redness, and yellowness. The obtained results showed that varied convective dehydration process parameters statistically significantly affected all investigated responses except activation energy. The most efficient drying model with the minimum thickness (3 mm) and the maximum drying temperature (70 °C) had the shortest drying time (231 minutes). This model had the minimum resistance to mass transfer (the minimum effective moisture diffusivity, 2.04. 10–08 – 7.12. 10–08 [m2s–1]), and the average maximum energy of activation (31.31 kJ/mol). As far as the carrot slices’ chemical composition and color parameters were concerned, the model with the maximum thickness (9 mm) and the minimum drying temperature (35 °C) was the optimal one. This model had the longest dehydration time (934 minutes), the maximum resistance to the mass transfer (8.87. 10–08 [m2s–1]), the minimum total protein content (5.26 %), and the darkest color (49.70). The highest protein content (7.91%) was found for the samples subjected to the highest drying temperatures and the lowest carrot slice thickness. In contrast, the process of convective dehydration had led to the lighter, reddish, and yellowish carrot slices. All developed mathematical models were statistically significan

Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

Fabrication of High-Entropy Alloys Using a Combination of Detonation Spraying and Spark Plasma Sintering: A Case Study Using the Al-Fe-Co-Ni-Cu System

The use of pre-alloyed powders as high-entropy alloy (HEA) coating precursors ensures a predetermined (unaltered) elemental composition of the coating with regard to the feedstock powder. At the same time, it is interesting to tackle a more challenging task: to form alloy coatings from powder blends (not previously alloyed). The powder-blend-based route of coating formation eliminates the need to use atomization or ball milling equipment for powder preparation and allows for the introduction of additives into the material in a flexible manner. In this work, for the first time, a HEA was obtained using detonation spraying (DS) followed by spark plasma sintering (SPS). A powder mixture with a nominal composition of 10Al-22.5Fe-22.5Co-22.5Ni-22.5Cu (at.%) was detonation-sprayed to form a multicomponent metallic coating on a steel substrate. The elemental composition of the deposited layer was (9 ± 1)Al-(10 ± 1)Fe-(20 ± 1)Co-(34 ± 1)Ni-(27 ± 1)Cu (at.%), which is different from that of the feedstock powder because of the differences in the deposition efficiencies of the metals during DS. Despite the compositional deviations, the deposited layer was still suitable as a precursor for a HEA with a configurational entropy of ~1.5R, where R is the universal gas constant. The subsequent SPS treatment of the substrate/coating assembly was carried out at 800–1000 °C at a uniaxial pressure of 40 MPa. The SPS treatment of the deposited layer at 1000 °C for 20 min was sufficient to produce an alloy with a single-phase face-centered cubic structure and a porosity of 0.3). The hardness of the coatings measured in two perpendicular directions did not differ significantly. The features of the DS–SPS route of the formation of HEA coatings and its potential applications are discussed

Revealing Changes in the Technical Parameters of the Teat Cup Liners of Milking Machines During Testing and Production Conditions

To implement effective cow milking, it is necessary to take into account the peculiarities of the milk flow process, the milking machine's adaptability to perform the given technological functions. The aim of research is to establish changes in the design and technological parameters and physical and mechanical properties of teat cup liner of milking machines during its testing and in production conditions. The results obtained will make it possible to make a rational choice of rubber, ensure an efficient milking process during its service life. It is found that the tensile strength of silicone teat cup liner at the beginning of operation was 1.6 times higher than that of a rubber compound, and after 6 months. operation – 1.7 times. With respect to the relative elongation, this difference was 1.4 times, and after operating time – 1.3 times. Studies have proven that rubber during operation changes its physical and mechanical properties: the length of the active part increased by 3.1 mm; wall thickness – 0.2 mm. It is found that the most intensively elastic properties of teat cup liner changed during the first 10–20 days. After 10 days, the closing vacuum increased by 16.6 % compared to the initial one, and after 20 days by 23.3 %, which amounted to 8.57 and 9.06 kPa, respectively. Up to 420 hours of operation, the clamping vacuum reached 11.3 kPa, which is 5.8 % lower than the requirements for toughening teat cup liner for rejection. In general, over the period of experiments, the average value of the vacuum of closing the opposite walls of teat cup liner increased from 7.35 to 12.43 kPa, which is 3.6 % higher than the norm (12 kPa). As a result of experimental studies, the regularity of the rubber tension force depending on the operating time in the form of a fourth degree polynomial is obtained. It is found that after 150 hours of operation, the tensile force of teat cup liner decreased by 21