Five hole-transporting triphenylamine derivatives containing methoxy and methyl groups are synthesized and investigated. The hole-mobility increases in the presence of methyl-and methoxy substituents, exceeding 10 -2 cm 2 /Vs in the case of the methyl groups. Quantum mechanical calculations on these compounds indicate very different dipole moments and intermolecular interaction strengths, with intriguing correlations to the trend in hole-mobility. Temperature dependent hole-mobility measurements indicate disorder dominated hole transport. The values of the energetic disorder parameter (σ) decrease upon methyl and methoxy substitutions despite the increase in dipole moments. This trend is discussed as a function of the interaction energy between adjacent molecules, the dipole moment, the molecular polarizability, and the conformational degree of freedom. Our results indicate that the global decrease of σ upon methyl and methoxy substitutions is dominated by the the larger decrease in the geometrical randomness component of the energetic disorder. A direct correlation is established between the decrease in geometrical randomness and the increase in intermolecular interaction energies, mainly stemming from the additional C-H….π,O,N hydrogen bonds induced by methyl and methoxy groups. the dipolar-moments on the energetic disorder, 6,7 methoxy substitutions are then expected to result in degraded-or improved charge transport properties, partly depending on the (respectively) important-or negligible increase of the molecular dipole moments. As will be shown in this study, the

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Synthesis, optical, thermal, electrochemical, and photoelectrical properties of new carbazole-and triphenylamine-based hydrazones with reactive vinyl groups are reported. Self-polymerization in the solid state of the synthesized monomers was studied by differential scanning calorimetry (DSC) and IR spectrometry. Molecular weights of the soluble polymers were determined by gel chromatography. The synthesized compounds were characterized by 1 H and 13 C NMR, IR, UV/VIS, fluorescence, and mass spectrometries, as well as by cyclic voltammetry. The synthesized carbazole-and triphenylamine-based hydrazones form glasses with the glass transition temperatures ranging from 83 to 118°C, as was elucidated by DSC. Their thermal degradation starts above 270°C, as was revealed by thermogravimetric analysis. The ionization potentials of the films of carbazole-and triphenylamine-based hydrazones, measured by the electron photoemission in air technique, range from 5.32 to 5.65 eV. Hole-drift mobilities in amorphous layers of the monomers, estimated by xerographic time of flight technique, approach 10 À3 cm 2 /Vs at high electric fields.

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Liucernostai vitaminų A, D, E ir K šaltinis. Augaluose taip pat yra daug fermentų, priešuždegiminį poveikį turinčių medžiagų, hormonų, β-karotino, vitamino B6, vitamino C ir vitamino U. Liucerna turi taninų, pektino medžiagų, saponinų, aminų, kumarino darinių, triterpeno glikozidų, karotinoidų, purino bazių, augalų sterolių, fitoestrogenų, flavonų, izoflavonoidų ir fenolinių junginių. Darbo tikslas-nustatyti ir atrinkti liucernų (Medicago L.) ir kaliaus kultūrų in vitro veisles, kaupiančias didžiausius bioaktyvių junginių kiekius. Nustatyta, kad didžiausias chlorofilo a kiekis buvo įvertintas liucernų veislėje Žydrūnė, išaugintose in vitro Murashige-Skoog (MS) terpėje-76,7 ± 0,06 mg/100g. Nustatyta, kad didžiausi bioaktyvių junginių kiekiai buvo liucernose, išaugintose in vitro MS terpėje: baltymų-veislėje Antanė (32 ± 0,07 mg/100 mg); vitamino C-veislėje Birutė (70,4 ± 0,01 mg/100 g); flavonoidų-veislėje Malvina (1,5 ± 0,01 %); fenolinių junginių-veislėje Antanė (0,07 ± 0,01 mg/100 mg). Didžiausias liucernų antioksidacinis aktyvumas prieš DPPH radikalą buvo nustatytas 22,3 ± 0,01 % liucernų veislėje Žydrūnė, o kaliaus kultūrose iš šaknų-26,36 ± 0,03 % veislėje Malvina, išaugintose in vitro MS terpėje su 2,4-dichlorofenoksiacto rūgštimi (2 mg/l) ir kinetinu (0,25 mg/l). Reikšminiai žodžiai: liucerna, kaliaus kultūra, bioaktyvūs junginiai, fitocheminis įvertinimas.