The yield of sugar beet depends not only on soil and climatic conditions, but also on the quality of the distribution of plants along the sowing series of these plants. The maximum yield is obtained with the optimal value of the average interval between plants, and all intervals should be the same with a coefficient of variation close to zero. A computer program has been computed for the relative yields, depending on the precision of the sowing and the germination of the seeds. The harvest is calculated in relative terms to exclude the influence of soil and weather conditions. For a maximum, the harvest is taken with the exact location of the optimal number of plants under the same germination conditions. The article contains a calculation program and a graphical representation of the results for sugar beet. This will help determine the rational limits of the number of plants per hectare and the accuracy of their distribution. The accuracy of the distribution of plants is estimated by the coefficient of variation of the intervals between them, which can take values from 0.2 to 1.0. The loss of yields from inaccurate distribution of plants along the row may reach 21%.

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On substitution of hydrogen by deuterium the radiation yield of free radicals in polyolefins decreases ca. 2‐fold. Under ultraviolet illumination (γ < 300 nm) in deuterated polyethylene (DPE), allyl radicals are converted into alkyl radicals (hfs constants a = 3.2 Oe, a = 4.4 Oe); in deuterated polypropylene (DPP), allyl and peroxide radicals are converted into alkyl radicals (a = 3.7 Oe). At 77°K under ultraviolet light in γ‐irradiated polyethylene (PE) and DPE, triene, tetraene, dienyl, trienyl, and tetraenyl radicals are formed. Deuterium substitution has no effect on absorption spectra of polyenyl radicals and polyenes. In polyolefins the quantum yields of photochemical reactions of allyl and peroxide radicals are 0.1–1.0. Photochemical reactions of peroxide radicals result in a radical concentration increase of ca. 3‐fold. In reactions of peroxide radicals in the dark, a kinetic isotope effect has been observed. Activation energies of substitution reactions of peroxide radicals are in PE, 9.3 ± 0.3 kcal/mole; in DPE, 10.2 ± 0.3 kcal/mole; in PP, 12.7 ± 0.4 kcal/mole; in DPP, 14 ± 0.5 kcal/mole. Possible mechanisms of the effect of polyolefin isotope composition on radical formation by high energy irradiation as well as on photochemical and dark reactions of free radicals are discussed. The effect of the energy released from phototransformations and radiationless deactivation of macroradicals on the migration of free valence is also considered.

The aim of the study is to search for the analytical dependence of the force of resistance of the wedge on the lifting angle in the case of working with wet soil, which does not crumble into fragments, but slides along the wedge in the form of a continuous tape. Tillage tools can have front and rear sharpening angles. The front angle raises the soil layer, and this action is most common in tillage. The rear corner seals the bottom of the furrow, so it is undesirable in plows. To determine the rational angle of inclination of the entire working surface under working conditions with wet soil, an analytical equation has been obtained, which is applicable if the technological indicators of the soil are observed in a particular field, especially indicators of soil sticking to the working surfaces. In this equation, the traction resistance of the wedge depends on the density of the soil, friction coefficient, tensile strength and shear strength. In the calculations, the deformation of the soil layer was taken inherent in the wetted state with the presence of plant residues, that is, the soil retains the shape of a continuous ribbon in its movement along the working surface of the wedge. According to the results of field studies of the experimental and basic plows, it was determined that on loamy soil with a moisture content of 16 to 22%, an rational angle of elevation of the tillage tool can be taken as an angle of 18 °. An experimental plow with a plowshare angle of 18 ° compared to a basic plow with a lifting angle of 30 ° showed an increase in productivity by 19% and a reduction in specific fuel consumption by 17% due to a decrease in traction resistance and, as a result, by reducing the likelihood of sticking of the soil and rare stops for cleaning the working bodies.

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