Isolation, purification and characterization of a complex heteroxylan from industriel wheat bran

International audienc

In-situ X-Ray diffraction for ionic-covalent material study under swift heavy ion irradiation

International audienceDue to increasing technologic interests for ceramics in electronuclear industry, studies of the evolution of material properties under swift heavy ion irradiation are highly topical. The effects of electronic excitation on structural properties for insulating ceramics has been highlighted, numerous questions are still remaining about driving forces which induce structural parameter evolutions. In this context, at IRRSUD beam-line (GANIL-Caen), which delivers typical 2 ions of fission products, an X-Ray diffractometer has been recently set up on line to get easy 7 access to phase transition kinetics under irradiation. It prevents problems of sampling variations and it offers possible combination of numerous irradiation parameters which is fundamental for phenomena understanding. By tilting the goniometer and using special vacuum chamber for ion beam propagation, in-situ grazing XRD measurements are possible during irradiation, the grazing configuration allowing the analysis of the only irradiated region. The communication will present the first results obtained on this device. As school cases for structural study, some insulating ionic-covalent materials have been picked up. Combination with microstructural analysis by transmission electron microscopy and point defect study by optical spectroscopy will be presented. Evidences with ion doses of latent tracks, amorphization or phase transitions will be highlighted

Influência do intervalo entre a colheita e a aplicação do 1-metilciclopropeno no controle do amadurecimento de mamão Influence of the interval between harvest and 1-methylcyclopropene application on papaya ripening

Este trabalho teve como objetivo determinar a influência do intervalo entre a colheita e a aplicação do 1-MCP na sua eficiência como retardador do amadurecimento de mamões 'Golden'. Os frutos foram colhidos em pomares comerciais da região de Linhares-ES, no estádio 2 de maturação, armazenados a 11&plusmn;1ºC e submetidos à aplicação de 1-MCP (100nL.L-1) após 0; 1; 2 e 3 dias da colheita. Frutos tratados e não-tratados permaneceram durante 6 dias a 11&plusmn;1ºC e, em seguida, foram armazenados a 22&plusmn;1,5ºC e 80-90%UR, até completo amadurecimento. O 1-MCP retardou a perda de firmeza e a mudança da cor da casca dos frutos. Os frutos sem 1-MCP atingiram firmeza ideal para consumo entre o 2º e o 4º dia a 22ºC. Os frutos que receberam 1-MCP no 2º ou no 3º dia após a colheita, atingiram ponto de consumo entre o 8º e o 10º dia a 22ºC. Aqueles tratados no 1º dia após a colheita atingiram firmeza de consumo no 12º dia a 22ºC, e aqueles que receberam 1-MCP no dia da colheita, não amoleceram. A coloração da casca teve comportamento similar ao da firmeza, porém em menor intensidade. Houve pequeno aumento no teor de sólidos solúveis dos frutos em função do amadurecimento. Quanto menor o intervalo entre a colheita e a aplicação do 1-MCP maior sua eficiência como retardador do amadurecimento de mamões 'Golden'. Essa informação é fundamental na definição da tecnologia de aplicação desse regulador vegetal.<br>The purpose of this work was to determine the influence of the interval between harvest and 1-MCP application on 1-MCP efficiency in delaying ripening in Golden papaya. Fruits were harvested from commercial orchards located in Linhares, ES, in a second stage of maturation, stored at 11&plusmn;1ºC and treated with 1-MCP (100 nL.L-1) 0, 1, 2 and 3 days after harvest. Treated and non-treated fruits were kept at 11&plusmn;1ºC for 6 days and, then, were stored at 22&plusmn;1.5ºC and 80-90%RH until complete ripening. 1-MCP delayed loss of firmness and skin color changes. Non-treated fruits reached ideal firmness for consumption between the 2nd and 4th day of storage at 22ºC. Fruits treated with 1-MCP on the 2nd or 3rd day after harvest reached consumption stage between the 8th and 10th day of storage at 22ºC. While fruits treated with 1-MCP one day after harvest reached optimum firmness for consumption on the 12th day of storage at 22ºC, those treated on the harvest day did not softened. Though more subtly, skin color behaved in a similar way as firmness. There was a slight increase in soluble solids amounts in fruits along ripening. The lower the interval between harvest and 1-MCP application, the longer the 1-MCP efficiency in delaying ripening in Golden papaya. This is the key information when defining the application procedure for 1-MCP as a ripening regulator