Fluorescence detection In aldehyde containing model systems: Relationship with fish deterioration

6 páginas, 4 tablas.[ES] En estudios previos se llevó a cabo la deteoeion de oempuestos de interacción a través de sus propiedades fluorescentes a distintos máximos de excitación/emisión durante el procesamiento de pescado, observándose un desplazamiento de la fluorescencia a longitudes de onda mayores como resultado del incremento de la alteración. En el presente trabajo se chequearon distintos tipos de aldehidos al objeto de comparar su capacidad para formar compuestos fluorescentes de distintas longitudes de onda en relación con el procesamiento de pescado. Dichos aldehidos (formaldehido, FA; acetaldehido, AcH; propanal, Pr; hexanal, Hex; 2-hexenal, Hx; benzaldehido, BzH) se hicieron reaccionar con músculo de sardina (Sardina pilchardus) desmenuzada y con n-propilamina a 30°C en oscuridad durante 25 días. Con el aumento del tiempo de reacción, todos los aldehidos estudiados mostraron capacidad para producir un desplazamiento a mayores longitudes de onda de la fluorescencia detectada. Sin embargo se observaron distintas aptitudes, de acuerdo con la estructura y la reactividad de cada aldehido. El desplazamiento fue especialmente pronunciado en los casos de Hx y AcH, mientras que fue bastante pequeño con FAy BzH. En una situación intermedia se situaron Pr y Hex, en los que al igual que durante la alteración de pescado, se observó un incremento en la relación entre las fluorescencias detectadas a 393/463 nm y 327/415 nm al avanzar el tiempo de reacción.[EN] In previous studies interaction compounds formation was accomplished by fluorescence detection at different excitation/ emission wavelength maxima during fish processing. Afluorescence shift towards higher wavelength maxima was then obtained as a result of damage increase. In the present work, different aldehydes were tested in order to compare their ability in producing fluorescent compounds with similar properties to the ones obtained during fish processing. Aldehydes (formaldehyde, FA; acetaldehyde, AcH; propanal, Pr; hexanal, Hex; 2-hexenal Hx; benzaldehyde, BzH) were reacted in model systems with sardine (Sardina pilchardus) muscle and with n-propylamine at 30°C in dark during 25 days. Afluorescence shift was detected for all the aldehydes investigated as long as the reaction time increased. Great differences were observed between aldehydes, according to their chemical structure and reactivity. A sharp shift was detected for Hx and AcH, while little changes were observed in the cases of FA and BzH. As in the case of fish processing, Pr and Hex showed an increasing ratio between fluorescences detected at 393/463 nm and 327/415 nm as long as the reaction time increased.Agradecemos a la Xunta de Galicia la ayuda financiera otorgada (Proyecto FAIR (CEE) CT 95-111).Peer reviewe

Проект гелиевой турбины в составе энергоблока АЭС с высокотемпературным газоохлаждаемым реактором

Целью работы является разработка проекта газовой турбины для энергоблока с высокотемпературным газоохлаждаемым реактором. Исходными данными для выполнения работы являются: высокотемпературный гелиевый реактор с температурой газа на выходе из реактора 1000 °С, конструктивные и энергетические характеристики компрессора, материалы преддипломной практики и данные научно-технической и учебной литературы, периодических изданий.

Improvement of Serviceability and Strength of Textile Reinforced Concrete by using Short Fibres

Nowadays, thin-walled load bearing structures can be realised using textile reinforced concrete (BRAMESHUBER and RILEM TC 201-TRC [1]). The required tensile strength is achieved by embedding several layers of textile. By means of the laminating technique the number of textile layers that can be included into the concrete could be increased. To further increase the first crack stress and the ductility as well as to optimize the crack development, fine grained concrete mixes with short fibres can be used. By a schematic stress-strain curve the demands on short fibres are defined. Within the scope of this study, short fibres made of glass, carbon, aramid and polyvinyl alcohol are investigated in terms of their ability to fit these requirements. On the basis of these results, the development of hybrid fibre mixes to achieve the best mechanical properties is described. Additionally, a conventional FRC with one fibre type is introduced. Finally, the fresh and hardened concrete properties as well as the influence of short fibres on the load bearing behaviour of textile reinforced concrete are discussed

Сравнительная характеристика торфов Томской области и республики Алтай

В данной работе была проведена сравнительная характеристика торфов Томской области и республики Алтай. Для этих торфов были определены технический и групповой составы. В результате исследований выявлено, что торфа с месторождений Томской области и республики Алтай отличаются по степени разложения и зольности. В торфах республики Алтай получили большее содержание гуминовых кислот и лигнина по сравнению с торфами Томской области . Кроме этого, в торфах республики Алтай выявлено низкое содержание битумов и углеводного комплекса и повышенное содержание гуминовых кислот и лигнина. Установлено, что на базе месторождений республики Алтай возможна организация производства гуминовых кислот и битумов в ограниченных размерах.In this work the comparative characteristic of peats of the Tomsk region and Altai Republic has been carried out. For these peats, the technical and group compositions were determined. As a result of the researches it is revealed that peats from deposits of the Tomsk region and Altai Republic differ on extent of decomposition and an ash-content. In peats of Altai Republic have received the bigger content of humic acids and a lignin in comparison with peats of the Tomsk region. Besides, in peats of Altai Republic the low content of bitumens and a carbohydrate complex and the increased content of humic acids and a lignin is revealed. It is established that on the basis of fields of Altai Republic the organization of production of humic acids and bitumens in limited sizes is possible

Познание и образование как основные элементы при изучении будущего

The article gives the overview of cognitive practices in philosophy. The authoremphasizes that there is a correlation between cognition and education.Integration of this two sides of a social life gives a possibility forfurther development of society

The Concept of "Nature’s Human" in the boundaries ecology-futurology’s investigation and obstacle they can to appear attached to his consideration

Стаття присвячена розробці питання "Людина природня" у рамках дослідження екологічної футурології та опису проблем її розуміння.This article is dedicate working out of question about "Nature’s Human" in the boundaries ecology futurology’s and describe problem’s attached to his understanding