The dielectric losses of Si2N2O, studied theoretically and experimentally up to 1573 K at 10 GHz, demonstrated an increase above 1000 K due to the impurity conduction losses, because of the small Li ...activation energy. Calculations based on the first-principles theory were performed to obtain the density of states. The optical and elastic properties of Si2N2O doped with a 4.8 % molar fraction of Li were modeled using a plane-wave pseudopotential method to investigate the effect of Li incorporation into Si2N2O. The polycrystalline static dielectric constants of Si2N2O increased after it was doped with Li. We also provided the optical properties of silicon nitride compounds to be used as references. The calculated elastic constants of pure and Li-doped Si2N2O indicated that the elastic modulus of the Li-doped Si2N2O was smaller than that of the pure Si2N2O. Additionally, Li-doped Si2N2O crystals were more brittle than the pure forms. Theoretical analyses of the dielectric losses and first-principles calculations emphasized that to consider Li-doped Si2N2O materials for applications, the dielectric losses and Li contents should be carefully optimized, since these factors also affect the conductivities of these materials.
Najbolj razširjena oblika vrste Brassica napus L. je oljna ogrščica, njeno seme pa je zaradi svojih fizikalnih lastnosti zelo mobilno in zato nagnjeno k raztrosu. Nenadzorovane izgube semena ...predstavljajo potencial za pojavljanje samosevnih in podivjanih populacij te vrste znotraj in zunaj pridelovalnih površin, saj se njeno seme ohranja in ostaja viabilno v tleh tudi več let. Dinamika pojavnosti teh rastlin je odvisna od potenciala talne semenske banke in kompleksih interaktivnih lastnosti genotipa semena ter pedoloških in agro-klimatskih dejavnikov. Prisotnost nedefiniranih opraševalnih virov, ki izvirajo iz talne semenske banke, pa v naravi predstavlja potencial za spontane intra- in inter-speciesne oprašitve vrste B. napus, kar vpliva na spremembe v njeni genetski strukturi.
The most common form of the Brassica napus L. is oilseed rape. Because of its physical characteristics the seed is very mobile and therefore disposed to spillage. Uncontrolled seed loss represents ...the potential for the appearance of volunteer and feral populations of B. napus inside and outside production areas; B. napus seed remains viable in the soil for several years. The appearance dynamics of these plants is dependent on the soil seed bank potential and complex interactive characteristics of the genotype seeds and soil and agro-climatic factors. The presence of undefined pollinating resources originated from soil seed bank in the nature presents the potential for spontaneous intra- and inter-species pollination of B. napus reflected also in its genetic structure.
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