Tag Archives: correlations

xxx I. Ivanova, M. Serdyuk, V. Malkina, О. Priss, T. Herasko and Т. Тymoshchuk
Investigation into sugars accumulation in sweet cherry fruits under abiotic factors effects
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Investigation into sugars accumulation in sweet cherry fruits under abiotic factors effects

I. Ivanova¹*, M. Serdyuk¹, V. Malkina, О. Priss¹, T. Herasko¹ and Т. Тymoshchuk²

¹Dmytro Motornyi Tavria State Agrotechnological University, 18, B. Khmelnytsky Ave, UA72312 Melitopol, Zaporizhzhia region, Ukraine
²Polissya National University, 7, Staryi Blvd, UA10008 Zhytomyr, Ukraine
*Correspondence: irynaivanova2017@gmail.com

Abstract:

The level of sugars content in sweet cherry fruit depends on many factors. However, the decisive influence of weather factors is noted. In view of this, the issue of predicting the sugars content in sweet cherry fruit depending on the share of weather factors is relevant for further improvement of transportation technology, storage and processing.
It has been established that according to sugars content and to the variability of their formation the most perspective from the technological point of view were varieties: Zabuta (12.47%), Dachnytsia (15.60%), Krupnoplidna (14.35%). Low and medium variabilities of the selected varieties according to the investigation years were established ( = 8.6%–13.0%). It has been shown that weather conditions had dominating effects on sugars accumulation for all varieties groups irrespective of the ripening period. According to the results of a two-factors dispersion analysis it is expedient to prognosticate the sugars content in sweet cherry fruits by medium values for a particular group of sorts but not for each pomological sort.
In the course of the work the average and strong correlation dependence between 14 weather factors (Хі, i = 1..14) and the sugars content for sweet cherries of early, medium, and late ripening period (|𝑟𝑌𝑗𝑋𝑖|≥0.55, 𝑖=1..14, 𝑗=1..3) were defined. The ranges of share of weather factors participation that have the maximum influence on sugars fund formation in sweet cherry fruit are established (Δ𝑖 9.50% to 30.99%) .
Based on regression analysis, it is substantiated that the sugars accumulation in sweet cherry fruit, regardless of the ripening period, is most influenced by weather conditions of the blossoming period, the last month of fruit formation and thermal parameters and humidity index at the stage of fruit picking.

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1218-1227 R. Rannaveski and M. Listak
Flash points of gasoline from Kukersite oil shale: Prediction from vapor pressure
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Flash points of gasoline from Kukersite oil shale: Prediction from vapor pressure

R. Rannaveski and M. Listak*

Tallinn University of Technology, School of Engineering, Department of Energy Technology, Ehitajate tee 5, EE19086 Tallinn, Estonia
*Correspondence: madis.listak@ttu.ee

Abstract:

The flash point of liquid fuels, especially of light distillates such as gasoline or naphtha, is an important parameter for the handling of such materials. In this work, flash points and volatility characteristics (vapor pressure, boiling point) of a number of shale gasoline samples with different volatilities were measured. The shale gasoline fractions were produced from Kukersite oil shale using solid heat carrier retorting technology. Several existing correlations for calculating flash points of hydrocarbons and petroleum fractions are evaluated, and the absolute average deviations were found to be between 1.1 to 20.9 °C. New, easy-to-use correlations are proposed for estimating flash points for oil shale based gasolines from volatility characteristic that are readily available. The correlation proposed in this work are based on the vapor pressure at 20 or 37.8 °C (100 °F), Reid vapor pressure (37.8 °C) or boiling point. The average absolute deviations for these correlations were 0.82 to 0.93 °C, meaning they are comparable to or better than existing methods developed for petroleum oils, which mostly use boiling point as the input parameter, when applied to gasoline from Kukersite oil shale.

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