Viscosity model of deep eutectic solvents from group contribution method

In this work, based on mathematical model inspired by transition state theory, the group contribution (GC) method is used to predict the viscosity of DESs. The model is constrained by Eyring rate theory and hard sphere free volume theory. A dataset of 2229 experimental measurements of the viscosity of 183 DESs from literature is used for determining the model parameters and subsequent verification of the model. The rules introduced by this model are simple and easy to understand. The results show that the proposed model is able to predict the DESs viscosity with very high accuracy, i.e., with an average absolute relative deviation of 8.12% over the training set and 8.64% over the test set, using only temperature and composition as inputs. The maximum absolute relative deviation is 34.63%. Therefore, the as-proposed model can be considered a highly reliable tool for predicting DESs viscosity when experimental data are absent.

Empirical Correlation of Emulsion Size Prediction for Zinc Extraction Using Flat Blade Impeller System in Emulsion Liquid Membrane Process

In this study, determination of droplets in the presence of blended mixture of surfactants (Span 80 and Tween 80) and nanoparticles, iron (III) oxide (Fe2O3) were investigated using a single stage mixer-settler extractor with 4-pitched flat blade impeller on one shaft employment. Additionally, the influence of Fe2O3 and blended surfactant mixture of Span 80 and Tween 80 on the dispersion of emulsion in terms of Sauter diameter (D32) measurement was compared with new correlations. Results indicate that the presence of Fe2O3 in the blended mixture of surfactant simultaneously decreased in D32 by 79 % and the stability of the emulsion system was enhanced. Overall, empirical correlation for droplet size at different conditions are obtained, and the modified correlation for D32 is presented. The correlation found is D32/DI =0.02265(3.419Φi−1)We-0.6. The calculated average absolute relative deviation (%AARD) is 2.69 %, thus indicating a good accuracy and acceptability between the presented correlation and experimental data.

Solubility Study of Acetylsalicylic Acid in Ethanol + Water Mixtures: Measurement, Mathematical Modeling, and Stability Discussion

Solubility determination of poorly water-soluble drugs is pivotal for formulation scientists when they want to develop a liquid formulation. Performing such a test with different ratios of cosolvents with water is time-consuming and costly. The scarcity of solubility data for poorly water-soluble drugs increases the importance of developing correlation and prediction equations for these mixtures. Therefore, the aim of the current research is to determine the solubility of acetylsalicylic acid in binary mixtures of ethanol+water at 25 and 37°C. Acetylsalicylic acid is non-stable in aqueous solutions and readily hydrolyze to salicylic acid. So, the solubility of acetylsalicylic acid is measured in ethanolic mixtures by HPLC to follow the concentration of produced salicylic acid as well. Moreover, the solubility of acetylsalicylic acid is modeled using different cosolvency equations. The measured solubility data were also predicted using PC-SAFT EOS model. DSC results ruled out any changes in the polymorphic form of acetylsalicylic acid after the solubility test, whereas XRPD results showed some changes in crystallinity of the precipitated acetylsalicylic acid after the solubility test. Fitting the solubility data to the different cosolvency models showed that the mean relative deviation percentage for the Jouyban-Acree model was less than 10.0% showing that this equation is able to obtain accurate solubility data for acetylsalicylic acid in mixtures of ethanol and water. Also, the predicted data with an average mean relative deviation percentage (MRD%) of less than 29.65% show the capability of the PC-SAFT model for predicting solubility data. A brief comparison of the solubilities of structurally related solutes to acetylsalicylic acid was also provided.

ANALYSIS OF DATA FOR FORECASTING SALES BY THE MOVING AVERAGE METHOD

The paper discusses methods of data analysis for forecasting sales using the example of a BigCar retail store that sells spare parts for trucks. Based on the information on sales for the calen-dar year, using the moving average method in MS Excel, the forecast values were calculated for three periods. Analysis of the calculated data showed that the smallest relative deviation is given by a four-month period.

Investigation of the rupture of a synthetic tape within the framework of the percolation theory

Within the framework of the percolation theory (bond problem), a new model of breaking a complex synthetic tape is proposed as a continuous-type phase transition when the state jump is zero. The percolation threshold and accompanying characteristics are calculated for the model of rupture of a synthetic reinforced tape when flowing along the first and second neighbours. The knots of the tape form a strip of a square lattice, the width of which is fixed. All nodes are intact and cannot be damaged, links (tape threads) can be intact and broken (blocked). The dependences of the percolation threshold in the bond problem and the relative deviation of the threshold from the ribbon length are calculated. It is proved that for the simplest model of one-dimensional percolation with percolation along the nearest neighbours (the problem of nodes), the percolation threshold in the thermodynamic limit is equal to unity. It is shown that, with an accuracy of 10%, the percolation threshold for a sufficiently long ribbon is equal to unity. This indicates that the system is quasi-one-dimensional. Thus, using the method of computer simulation, the percolation threshold, root-mean-square and relative threshold deviations were calculated. The critical susceptibility index was also calculated. In contrast to the usual percolation problem, in the proposed model it makes sense to consider only the region above the percolation threshold. The proposed model can be generalized to the case when nodes are also damaged (blocked), then we come to a mixed percolation model, which is supposed to be considered in the future.

The Association Between The Impact Factor of A Journal And The Trueness of Findings Published Therein: A Meta-Epidemiological Study

Background: Scientists, physicians, and the general public legitimately expect scholarly publications to give true answers to study questions raised. We investigated whether findings from studies published in journals with higher Journal Impact Factors (JIFs) are more accurate than findings from studies in less-cited journals via a meta-epidemiological approach.Methods: We screened intervention reviews from the Cochrane Database of Systematic Reviews (CDSR) and sought well-appraised meta-analyses. We defined the trueness of RCT study results as their point estimates’ relative deviation from the pooled effect estimate. In addition to the JIF we considered the open-access policy of journals, the relative size of studies, and the studies’ methodical quality.Results: In 2,459 results from 446 meta-analyses, there was a positive association between a journal’s JIF and the trueness of the study results published therein (Pearson’s r for the deviation = −0.21, 95% CI −0.24 to −0.17, P < 0.001). The mean relative deviation decreased from 1.11 (SD = 0.94) in the lowest JIF quartile to 0.80 (SD = 0.75) in the top quartile (95% CI: 0.21 to 0.40, P < 0.001). Findings from larger and methodically sound studies were also more likely to be accurate. In a multiple regression analysis, the JIF proved to be the strongest determinant of trueness, independent of the covariates.Conclusions: Our results indicate that higher-impact journals act as gatekeepers in the process of science more effectively than less-cited journals. However, the fact alone that a study result is reported in a journal with a high impact factor is only a weak and impractical indicator for its accuracy.

Ultrasonic Exposure of the Liquid Film for Highly Efficient Gas Absorption

A model of ultrasonic intensification of the absorption process is proposed, developed, and analyzed. For the first time, the model takes into account the effect of wave-like capillary perturbations of the liquid-gas surface and the acceleration of diffusion in the liquid volume on the absorption rate due to cavitation. According to the results of the model researches, the need for uniform sounding of the extended surface of the liquid film is established to accelerate the absorption of carbon dioxide and other harmful and target gaseous impurities by at least 3 times. The designs and layout of ultrasonic vibration radiators with an extended radiation surface are proposed. The results of measurements of the vibration amplitudes of the invented transducers showed that they have a relative deviation of the amplitude of no more than 0.2. The proposed approaches to the implementation of the process can be recommended for further research, the selection of optimal designs, and industrial applications to accelerate the absorption of gaseous impurities

The international calibration procedure for B3 film dosimetry system to ensure the quality irradiated products by 10 MeV electron beam accelerators at VINAGAMMA

We performed an in-plant calibration of dosimetry system by electron beam (EB)irradiating the B3 film dosimeters at VINAGAMMA, and inter-compared with the alanine dosimetry, which were supplied and analyzed by Risø High Dose Reference Laboratory (HDRL) as the reference standard. The results revealed that the relative deviation between the values of absorbed doses obtained with our dosimeter and the transfer standards dosimeter measured by HDRL was within the acceptable limitation (about ± 3.0 % in the target range of 2.0-10.0 kGy). And post-irradiation stability of B3 film dosimeters was still maintained after 180 days storage. It is suggested that the B3 filmdosimetry could be used in routine radiation processing at VINAGAMMA with the investigated dose range for quality assurance of the irradiated products, specially are foods and foodstuffs processed under the 10 MeV EB accelerator at VINAGAMMA.

Discharge of a Triangular Orifice under Free Flow Conditions

In this paper, flow through a free triangular orifice is considered. The comparison of two formulas was conducted for discharge calculations: a large orifice formula and a small orifice formula. The results show that, above a certain value of upstream head to orifice height ratio there is no need for small-large formula discrimination. The differences in the outcomes for the two formulas are negligible for upstream head to orifice height ratios greater than 3. This means that a small orifice formula can be used instead of a large orifice formula. Calculations were performed for different variants of triangle orientation (with tip downwards, sidewards and upwards) as well as for different dimensions of orifice (equilateral and isosceles). The calculations also included different submergence levels of the upper edge of the orifice and variable dimensions of the orifice with constant upstream head. Neither of these conditions affect the relative deviation values for small and large orifice formulas.

Solubility of vitamin A in supercritical CO2: experimental study and thermodynamic modeling

One of the best methods of extracting Vitamin A, as a helper of the immune body system and vision, was measured in supercritical carbon dioxide (SC-CO2); Mole fractions were gained at practical conditions in which the temperature was in the range of 303–323 K and the pressure range was 90–235 bar, respectively. Moreover, four Equation of States [Soave–Redlich–Kwong, Peng–Robinson, Stryjek–Vera and Dashtizadeh–Pazuki–Taghikhani–Ghotbi (DPTG)] were compared with the experimental data. Also, the mixing rules of Van der Waals (vdW1 and vdW2) selected to correlate the solubility data of vitamin A. The outcomes indicate that each of EOSs coupled with vdW2, as a method of estimating the physicochemical and critical properties, were correlated with the solubility data of vitamin A in SC-CO2 with more accuracy, in comparison with vdW1. Among the cubic EOSs, the DPTG model with vdW2 generated the most suitable correlation with the percentage average absolute relative deviation (Average Absolute Relative Deviation%) of 6.