Water molecular state in 1-hexylpyridinium hexafluorophosphate: Water mean cluster size as a function of water concentration

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Radio-frequency magnetron sputtering A versatile tool for CdSe quantum dots depositions with controlled properties

International audienceCdSe nanoparticles are of great interest for many applications. However, their size, shape, and aggregation are still difficult to control by the conventional synthesis methods. Here, we report on the synthesis of CdSe quantum dots (QDs), with an average diameter less than 10 nm, using radio-frequency magnetron sputtering (RFMS) on glass and silicon substrates at 25 °C. First, results show that a target-substrate distance of 13.5 cm and a chamber pressure of 2.2.10-1 mbar were required to deposit a CdSe QDs layer on the substrates. The morphology and optical properties of CdSe QDs were then studied as a function of RF power and deposition time. The size of CdSe QDs increases with increasing both the RF power and the deposition time. UV-visible spectroscopy shows that the CdSe QDs layer deposited on the glass-substrate by RFMS has almost the same optical properties as the one obtained from commercial CdSe QDs solutions. In both cases, a shift of the characteristic absorption band of CdSe QDs towards the higher wavenumbers is observed with the QDs size increase. AFM confirms the success of CdSe QDs layer deposition by RFMS CdSe QDs with a mean diameter of 7.5 ± 2 nm were observed for a RF power of 14 W, a chamber pressure of 2.2.10-1 mbar, a target-substrate distance of 13.5 cm and a deposition time of 7.5 min (optimal values). With these parameters, the coverage of the substrate by the nano-objects is estimated at 25-30 % of the overall surface

Radio-frequency magnetron sputtering A versatile tool for CdSe quantum dots depositions with controlled properties

International audienceCdSe nanoparticles are of great interest for many applications. However, their size, shape, and aggregation are still difficult to control by the conventional synthesis methods. Here, we report on the synthesis of CdSe quantum dots (QDs), with an average diameter less than 10 nm, using radio-frequency magnetron sputtering (RFMS) on glass and silicon substrates at 25 °C. First, results show that a target-substrate distance of 13.5 cm and a chamber pressure of 2.2.10-1 mbar were required to deposit a CdSe QDs layer on the substrates. The morphology and optical properties of CdSe QDs were then studied as a function of RF power and deposition time. The size of CdSe QDs increases with increasing both the RF power and the deposition time. UV-visible spectroscopy shows that the CdSe QDs layer deposited on the glass-substrate by RFMS has almost the same optical properties as the one obtained from commercial CdSe QDs solutions. In both cases, a shift of the characteristic absorption band of CdSe QDs towards the higher wavenumbers is observed with the QDs size increase. AFM confirms the success of CdSe QDs layer deposition by RFMS CdSe QDs with a mean diameter of 7.5 ± 2 nm were observed for a RF power of 14 W, a chamber pressure of 2.2.10-1 mbar, a target-substrate distance of 13.5 cm and a deposition time of 7.5 min (optimal values). With these parameters, the coverage of the substrate by the nano-objects is estimated at 25-30 % of the overall surface

Effect of cold plasma surface treatment on the properties of supported ionic liquid membranes

International audienc

The profitability of P.G. 600 in well managed sow herd

Adequate results in reproduction are one of the key points for successful pig production. P.G. 600, a combination of pregnant mare serum gonadotropine and human chorionic gonadotropine is used as oestrus promoter on many pig farms. The profitability of P.G. 600 treatment was tested on primiparous sows on well managed farm with 2.500 sows and 14.04 liveborn piglets per litter. The experiment lasted for a period of one year. The experimental group, 502 animals, was treated with P.G. 600 at weaning of the first litter. Control group, 503 animals, was not treated. Data were evaluated according to four seasons: spring, summer, autumn and winter. The costs of feed, sow depreciation, building, labour and P.G. 600 treatment in experimental group were calculated for the period from weaning to successful insemination or fromweaning to culling. In P.G. 600 group production costs were lower in spring (-0.68 EUR per born piglet) and in summer (-0.88 EUR per born piglet), but not in autumn (+0.05 EUR per born piglet) and in winter (+0.46 EUR per born piglet). The calculated total benefit on the farm with yearly production of 65 thousand 30 kg pigs was 3,249 EUR. Calculated benefit for only spring and summer use was 4.937 EUR. The last number represents only 0.15 to 0.19% of estimated turnover of the farm. The use of P.G. 600 on well managed farm will not increase profitability of production.Primerni rezultati reprodukcije so ključnega pomena za uspešno prašičerejsko proizvodnjo. P.G. 600, ki je kombinacija serumskega gonadotopina brejih kobil in človeškega horionskega gonadotropina, se pogosto uporablja kot spodbujevalec estrusa. Gospodarnost uporabe P.G. 600 smo preizkusili na svinjah prvesnicah na dobro vodenem obratu z 2.500 svinjami in 14,04 živorojenimi pujski po gnezdu. Poskus je trajal eno leto. Poskusno skupino, 502 živali, smo tretirali s P.G. 600 ob odstavitvi prvega gnezda. Kontrolne skupine, 503 živali, nismo tretirali. Podatke smo obdelali po štirih letnih sezonah: pomlad, poletje, jesen in zima. Stroške za krmo, amortizacijo svinje in objektov ter opreme, dela in tretiranja s P.G. 600 v poskusni skupini smo ocenili za obdobje od odstavitve do uspešne osemenitve ali do izločitve. Stroški v skupini, tretirani z P.G. 600, so bili nižji spomladi (-0,68 EUR po rojenem pujsku) in poleti (Ž0,88 EUR po rojenem pujsku), ne pa jeseni (+0,05 EUR) in pozimi (+0,46 EUR). Na farmi z letno proizvodnjo 65 tisoč 30 kg težkih pujskov so se stroški znižali za 3.249 EUR. Če bi preparat uporabljali le spomladi in poleti, bi privarčevali 4.973 EUR. To predstavlja le 0,15 do 0,19 % letnega prihodka farme. Uporaba P.G. 600 na dobro vodenem obratu ne bi izboljšala gospodarnosti

Chemical and physicochemical characterizations of the water-soluble fraction of the Commiphora Africana exudate

International audienceThe present study focuses on the chemical and physical characterization of the water-soluble fraction of the Commiphora Africana exudate. The chemical analysis proved that this fraction is mainly composed of carbohydrates and hydrophobic amino acids. Size exclusion chromatography (SEC) revealed the presence of three distinct polysaccharide populations that are all bonded to protein. In addition, both SEC and rheology demonstrated that the gum owns highly compact structure that suggests an AGP-like polymer. commiphora Africana gum exhibits excellent surface activity at concentration 2 orders of magnitude lower than the reference, acacia gum and was attributed to the fact that the three populations contribute to the surface tension lowering. This remarkable property has been confirmed by preliminary experiments on model emulsions and suggests a very promising application in formulation

Rhamnolipids From Pseudomonas aeruginosa Are Elicitors Triggering Brassica napus Protection Against Botrytis cinerea Without Physiological Disorders

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Semipurified Rhamnolipid Mixes Protect Brassica napus Against Leptosphaeria maculans Early Infections

International audienc

Image_2_Rhamnolipids From Pseudomonas aeruginosa Are Elicitors Triggering Brassica napus Protection Against Botrytis cinerea Without Physiological Disorders.TIF

<p>Rhamnolipids (RLs) are amphiphilic molecules naturally produced by some bacteria with a large range of biological activities. Although some studies report their potential interest in plant protection, evaluation of their effects and efficiency on annual crops of worldwide agronomic interest is lacking. The main objective of this work was to investigate their elicitor and protective activities on rapeseed crop species while evaluating their physiological effects. Here we report that RLs from Pseudomonas aeruginosa secretome trigger an effective protection of Brassicanapus foliar tissues toward the fungus Botrytis cinerea involving the combination of plant defense activation and direct antimicrobial properties. We demonstrated their ability to activate canonical B.napus defense responses including reactive oxygen species production, expression of defense genes, along with callose deposits and stomatal closure as efficient physical protections. In addition, microscopic cell death observations and electrolyte leakage measurements indicated that RLs trigger a hypersensitive response-like defense in this plant. We also showed that foliar spray applications of RLs do not induce deleterious physiological consequences on plant growth or chlorophyll content and that RL protective properties are efficient on several grown cultivars of rapeseed. To our knowledge, this is the first report of RLs as an elicitor that suppresses fungal disease on tissues of an annual crop species under greenhouse conditions. Our results highlight the dual mode of action of these molecules exhibiting plant protection activation and antifungal activities and demonstrate their potential for crop cultures as environmental-friendly biocontrol solution.</p

Image_4_Rhamnolipids From Pseudomonas aeruginosa Are Elicitors Triggering Brassica napus Protection Against Botrytis cinerea Without Physiological Disorders.TIF

<p>Rhamnolipids (RLs) are amphiphilic molecules naturally produced by some bacteria with a large range of biological activities. Although some studies report their potential interest in plant protection, evaluation of their effects and efficiency on annual crops of worldwide agronomic interest is lacking. The main objective of this work was to investigate their elicitor and protective activities on rapeseed crop species while evaluating their physiological effects. Here we report that RLs from Pseudomonas aeruginosa secretome trigger an effective protection of Brassicanapus foliar tissues toward the fungus Botrytis cinerea involving the combination of plant defense activation and direct antimicrobial properties. We demonstrated their ability to activate canonical B.napus defense responses including reactive oxygen species production, expression of defense genes, along with callose deposits and stomatal closure as efficient physical protections. In addition, microscopic cell death observations and electrolyte leakage measurements indicated that RLs trigger a hypersensitive response-like defense in this plant. We also showed that foliar spray applications of RLs do not induce deleterious physiological consequences on plant growth or chlorophyll content and that RL protective properties are efficient on several grown cultivars of rapeseed. To our knowledge, this is the first report of RLs as an elicitor that suppresses fungal disease on tissues of an annual crop species under greenhouse conditions. Our results highlight the dual mode of action of these molecules exhibiting plant protection activation and antifungal activities and demonstrate their potential for crop cultures as environmental-friendly biocontrol solution.</p