Climate change, soil degradation, and the spread of seed-borne pathogens pose serious challenges to global food security and agricultural sustainability. Although chemical seed treatment provides pathogen control, it poses environmental and health risks. This review analyses innovative seed treatment technologies, with particular emphasis on ozonation as an ecologically viable alternative. The mechanisms of action of ozone, its effects on seed germination, reduction of microbial contamination, and crop establishment are discussed. Chemical, physical, and biological treatment methods are comparatively evaluated, analyzing their effectiveness, environmental impact, and application limitations.

Due to environmental pollution and global warming, the use of renewable energy sources such as agricultural residues is gaining attention. Corn is the main source of food in many countries, and after harvesting it, the agricultural and industrial sectors generate significant amounts of residues. This study focused on corncob processing, its preparation, and the evaluation of its characteristics for energy needs. There was no significant difference between drying with active ventilation in the dryer and outdoor drying conditions. The adequate moisture content of corncob pellets is 12.39% at a compression ratio of 3.43 ± 0.011 and a maximum pellet density of 1012.96 ± 3.35 kg m⁻³. The variation in pellet density at a given adequate moisture content is at least 0.78%. The compression ratio of the pellets compacted on the horizontal matrix granulator is 9.75% higher than that of the pellets produced on the laboratory automatic press. The corncob’s lower calorific value was 17.35 ± 0.14 MJ kg⁻¹, and the ash content was 1.78 ± 0.24%. The produced pellets are strong enough and can be used for combustion. This research may help to better understand the properties of corncobs and their energy potential.

When temperature in the leaf gas exchange system changes, the thermodynamic parameters describing the condition of moist air also change. A temperature change of 1 oC in plant leaf tissues leads to a change in partial water vapour pressure of 144 Pa in the gas exchange cavities. Then a temperature decrease of 1 oC in a plant leaf produces 0.897 g of condensate, from 1 m3 of air in leaf ventilation cavities on the surface. When the temperature of plant leaves in the leaf ventilation system changes, the total water vapor state on the inner surface of the leaves changes, and the water vapor state in the stomatal cavities changes. The thickness of the formed condensate film on the plant leaf canal wall surfaces depends on the canal diameter and temperature change. The paper presents information about the mechanism of water formation and thermodynamic processes in the plant leaf gas exchange system participating in the process of assimilation. The formation and change of the internal surfaces of the stomatal cavities of the water film sheet allow the participation of chemical processes in the assimilation of CO2 emissions from the environment.

The article analyses the processes of heat circulation in the plate regularly supplying the varying flow of heat. The construction of the plate where the heat energy is transformed into mechanical work is presented. Applying the method of idealization the working principle and the principal construction of engine converting heat to mechanical work are introduced. The thermodynamic cycle of engine with the processes within are examined. With temperature change by 1°C the thermal efficiency coefficient of engine will be below 0.0034. The theoretical cycle of heat transference into mechanical energy does not encounter the loss of energy. This results from the assumption that after having activated the circulation processes in the border layer and performed a certain mechanical work finally the mechanical energy is reconverted to heat.DOI: http://dx.doi.org/10.5755/j01.mech.19.3.4661

In the technical field, the potential energy of gas under pressure is converted into mechanical kinetic energy by means of special complex channels. Leaf stomata perform a similar function in plant leaves. The shape of leaf stomata channels is much more sophisticated compared to gas flow transformation channels in energy production facilities. There is a biological prototype of a heat engine in the leaf, where leaf stomata convert thermal energy into mechanical kinetic energy of the flow with a change in leaf temperature. The paper presents experimental research on thermal energy conversion into mechanical kinetic energy of the flow in plant leaf stomata. The values of biological heat engine in a plant leaf and the associated processes are minute. The operation of the biological heat engine in a plant leaf was proven by indirect experimental measurements. After applying a light source flux to a plant leaf and inducing a temperature change in the tissues of the plant leaf, the rotational movements of a freely hanging plant leaf about the suspension axis were studied. When studying the dependence of plant leaf rotation movements on the area of the plant leaf, it was found that at a 150 W light source, the angle of rotation increased as the area of the plant leaf increased. For a plant leaf with an area of 52.5 ± 1.9 cm², the angle of rotation reached 165°; 29.1 ± 1.1 cm²—143°; 16.0 ± 0.8 cm²—92°; and 9.2 ± 0.6 cm²—44°. The angular speed of plant leaf rotation was from 0.070–0.262 rad/s. The influence of light sources on the rotation angle of the plant leaf was studied; when illuminating the active leaf area of 25.0 ± 1.0 cm² of the plant with a 40 W power light source, after 11 s, the rotation angle reached 31°, 60 W—97°, 100 W—131° and 150 W—134°. The effect of light sources (from 40 to 150 W) on the angular rotation speed of the plant leaf varies at 0.049–0.213 rad/s, respectively.

Saulė spinduliavimo būdu teikia Žemei šilumos energiją, kurią augalija panaudoja biomasės kūrimui. Augaluose sukurta biomasė gali išskirti energijos tik tiek, kiek biomasės gamybos procese augalija įsisavino Saulės spindulinės energijos. Gam­toje sukurtos biomasės kiekis (energetikai ir maistui) tiesiogiai priklauso nuo augalijoje vykstančio asimiliacijos proceso ir augalų energinio produktyvumo. CO₂ asimiliacijos procese vyksta sudėtingi biologiniai ir fiziniai energinės apykaitos pro­cesai. Straipsnyje pateikiama informacija, kaip augalas augimvietėje kintančius terminius veiksnius ir procesus panaudoja asimiliacijos procesui intensyvinti. Analizuojami augalo lapo žiotelinio variklio termodinaminiai procesai, lemiantys energijų virsmus. Pateikiamas Saulės energijos transformavimo į mechaninę energiją augalo lapo žioteliniame variklyje principas.