Occurrence of arbuscular mycorrhizal fungi in the roots of two grapevine cultivars in response to bioproducts

The aim of this study was to determine the influence of different bioproducts on the occurrence of arbuscular mycorrhizal fungi (AMF) in the roots of ‘Solaris’ and ‘Regent’ grapevine cultivars. The following bioproducts were used, alone or with mineral fertilization (NPK): Ausma, Bioilsa, manure and BF Ekomix. The highest mycorrhizal frequency was recorded in the roots of ‘Solaris’ after applying the bioproduct Ausma. For the ‘Regent’ cultivar, the highest mycorrhizal frequency was found in the plants treated with Ausma, BF Ekomix and manure. Colonization of grapevine roots by AM fungi was limited bymineral fertilization. After the combined use of bioproducts and mineral fertilizers, there was observed a tendency for minimized negative effect of mineral fertilization on the formation of arbuscular mycorrhizal fungi

CONTRIBUTION A L'ETUDE DES PROPRIETES OPTIQUES LINEAIRES ET NON LINEAIRES DES SEMI-CONDUCTEURS A I IB V I

ANGERS-BU Lettres et Sciences (490072106) / SudocSudocFranceF

Structural, morphological and photoluminescent properties of annealed ZnO thin layers obtained by the rapid sol-gel spin-coating method

ZnO thin layers were deposited on p-type silicon substrates by the sol-gel spin-coating method and, then, annealed at various temperatures in the range of 573-873 K. Photoluminescence was carried out in the temperature range of 20-300 K. All samples showed two dominant peaks that have UV emissions from 300 nm to 400 nm and visible emissions from 400 nm to 800 nm. Influence of temperature on morphology and chemical composition of fabricated thin layers was examined by XRD, SEM, FTIR, and Raman spectroscopy. These measurements indicate that ZnO structure is obtained for samples annealed at temperatures above 573 K. It means that below this temperature, the obtained thin films are not pure zinc oxide. Thus, annealing temperature significantly affected crystallinity of the thin films

Optical properties of styrylquinoline containing copolymers withdifferent substituents

International audienceStyrylquinolines (StQs) are derivatives of stilbene and can undergo various photochemical reactions [1]. They have two activecentres: ethylene group and an endocyclic nitrogen atom. Styryl dyes [2], and styrilquinoline containing compounds were usedfor various sensitive materials, such as sensitizers or desensitizers. The development of new technologies leads to the discoveryof new applications for styrylquinoline dyes in the fields of electroluminescence [3], photochromism [4], and pharmacy [5]. Thestudy of the photochemical properties of 2-styrylquinoline and its several derivatives showed that substituents in the styrylmoiety increase the quantum efficiency of photoisomerization [6].The aim of the study was to present the influence of various substituents on luminescence and optical properties ofstyrylquinoline copolymers. The thin films of synthesized compounds were prepared using the spin-coating technique(Spin200i, POLOS) at a spin rate of 1500 rpm for 60 s. Immediately after the deposition, the films were cured in an oven at50ºC for 180 minutes in order to eliminate any residual solvent. Optical parameters were obtained from absorbancemeasurements. The luminescent properties of prepared thin layers on glass substrates were registered by the HITACHI f-2500fluorescence spectrophotometer in the range of 360-600 nm (λex. = 340 nm, Xe lamp).References:[1] E.N. Gulakova, D.V. Berdnikova, T.M. Aliyeu, Y.V. Fedorov, I.A. Godovikov, O.A. Fedorova, “Regiospecific C-N photocyclization of 2-styrylquinolines,” J. Org. Chem. 79, 5533–5537 (2014).[2] T. Deligeorgiev, A. Vasilev, S. Kaloyanova, J.J. Vaquero, “Styryl dyes – synthesis and applications during the last 15 years,” Soc. Dyers Col. 126, 55–80 (2010).[3] M. Rams-Baron, M. Dulski, A. Mrozek-Wilczkiewicz, M. Korzec, W. Cieslik, E. Spaczyńska, P. Bartczak, A. Ratuszna, J. Polanski, R. Musiol, “Synthesis of New Styrylquinoline Cellular Dyes, Fluorescent Properties, Cellular Localization and Cytotoxic Behavior,” PLoS ONE 10(6), 1-17 (2015).[4] M.F. Budyka, N.I. Potashova, T.N. Gavrishova, V.M. Li, “Design of fully photonic molecular logic gates based on the supramolecular bis-styrylquinoline dyad,” Nanotechnol. Russ. 7, 280–287 (2012).[5] F. Mao, J. Yan, J. Li, X. Jia, H. Miao, Y. Sun, L. Huang, X. Li, “New multi-target-directed small molecules against Alzheimer’s disease: a combination of resveratrol and clioquinol,” Org. Biomol. Chem. 12, 5936–5944 (2014).[6] M.F. Budyka, N.I. Potashova, T.N. Gavrishova, V.M. Li, “Photoisomerization of 2-styrylquinoline in neutral and protonated forms,” High Energy Chem. 42, 446–453 (2008)

Optical properties of styrylquinoline containing copolymers withdifferent substituents

International audienceStyrylquinolines (StQs) are derivatives of stilbene and can undergo various photochemical reactions [1]. They have two activecentres: ethylene group and an endocyclic nitrogen atom. Styryl dyes [2], and styrilquinoline containing compounds were usedfor various sensitive materials, such as sensitizers or desensitizers. The development of new technologies leads to the discoveryof new applications for styrylquinoline dyes in the fields of electroluminescence [3], photochromism [4], and pharmacy [5]. Thestudy of the photochemical properties of 2-styrylquinoline and its several derivatives showed that substituents in the styrylmoiety increase the quantum efficiency of photoisomerization [6].The aim of the study was to present the influence of various substituents on luminescence and optical properties ofstyrylquinoline copolymers. The thin films of synthesized compounds were prepared using the spin-coating technique(Spin200i, POLOS) at a spin rate of 1500 rpm for 60 s. Immediately after the deposition, the films were cured in an oven at50ºC for 180 minutes in order to eliminate any residual solvent. Optical parameters were obtained from absorbancemeasurements. The luminescent properties of prepared thin layers on glass substrates were registered by the HITACHI f-2500fluorescence spectrophotometer in the range of 360-600 nm (λex. = 340 nm, Xe lamp).References:[1] E.N. Gulakova, D.V. Berdnikova, T.M. Aliyeu, Y.V. Fedorov, I.A. Godovikov, O.A. Fedorova, “Regiospecific C-N photocyclization of 2-styrylquinolines,” J. Org. Chem. 79, 5533–5537 (2014).[2] T. Deligeorgiev, A. Vasilev, S. Kaloyanova, J.J. Vaquero, “Styryl dyes – synthesis and applications during the last 15 years,” Soc. Dyers Col. 126, 55–80 (2010).[3] M. Rams-Baron, M. Dulski, A. Mrozek-Wilczkiewicz, M. Korzec, W. Cieslik, E. Spaczyńska, P. Bartczak, A. Ratuszna, J. Polanski, R. Musiol, “Synthesis of New Styrylquinoline Cellular Dyes, Fluorescent Properties, Cellular Localization and Cytotoxic Behavior,” PLoS ONE 10(6), 1-17 (2015).[4] M.F. Budyka, N.I. Potashova, T.N. Gavrishova, V.M. Li, “Design of fully photonic molecular logic gates based on the supramolecular bis-styrylquinoline dyad,” Nanotechnol. Russ. 7, 280–287 (2012).[5] F. Mao, J. Yan, J. Li, X. Jia, H. Miao, Y. Sun, L. Huang, X. Li, “New multi-target-directed small molecules against Alzheimer’s disease: a combination of resveratrol and clioquinol,” Org. Biomol. Chem. 12, 5936–5944 (2014).[6] M.F. Budyka, N.I. Potashova, T.N. Gavrishova, V.M. Li, “Photoisomerization of 2-styrylquinoline in neutral and protonated forms,” High Energy Chem. 42, 446–453 (2008)

APPLICATION OF THE MINIRHIZOTRON TECHNIQUE TO STUDYING THE ROOTS OF FRUIT PLANTS

Minirhizotron, a non-destructive technique is based on the application of transparent tubes, located in plant’s root zone. This method has been known since the beginning of 20th century and is used for plant root’s observations, especially in forest trees (Scots pine, Norway spruce, silver fir, birch), steppe grasses, vegetables and cereals. Minirhizotron technique is also applicable to pomological plants observations, mostly apples, but many others orchard species were observed with this method last years. The study of root growth dynamics in fruit plants using the non-destructive, minirhizotron method is conducted in the Pomological Orchard in Skierniewice. The objects of the observations are the roots of: apple trees cultivar. ‘Gold Milenium’, blackcurrant bushes cultivar ‘Tiben’ and sweet cherry cultivar ‘Vanda’. The observations were carried out monthly over a period of from March to November

ZnO nanostructures for lightning, solar cells and gas sensors

International audienceA great economic progress in white LEDs and photovoltaic (PV) markets is possible thanks to the use of lanthanide-free phosphors that are supposed to convert UV light into visible one, thanks to down-conversion (DS) process. ZnO nanoparticles (NPs) have aroused a growing interest, since due to the size reduction, they possess a variety of intrinsic defects (Zn vacancies and O interstitials). These defects can behave as efficient light-emitters, which provide light emission in the visible range. ZnO NPs naturally absorb the UV light thanks to a wide band gap of about 3.37 eV and it can also emit visible light, from yellow to red, depending on the nature of the crystalline and surface defects involved in the emission process. This is so-called “down-shifting”. However, the stability in time of their high photoluminescent quantum yield (PL QY) and easy to scale–up fabrication process (expected for industrial applications) are still challenging issues. Our collaborators from IRCELyon developed a quick and convenient chemical solution approach to get unique mesospheric self-assembly hybrid ZnO system with intense photoluminescent quantum yield of 40-75 % and stable visible emissions. This chemical process is industry-capable and cost effective. The use of a mixture of commercial polyacrylic acid-based polymers can provide large scale amounts of ZnO NPs in clear water suspensions that can be dried and dispersed again in water and the high PL QY is still preserved. The surface functionalization of ZnO NPs also influences their PL QY and the enhancement of this parameter is observed for some specific procedures applied during the synthesis process. ZnO NPs emitting in the visible spectral range can be applied for LED lightning as phosphors or the down-shifting layer on the top of solar cells in order to increase their efficiency in the UV spectral zone