Silane modification of the flax/epoxy system interface

Natural fibres (NF) are normally subjected to pre-treatment to ensure good fibre to matrix bonding and consequent mechanical properties and durability. To enhance the sustainability of NF composite systems, it would be sensible to minimise processes that incur environmental burdens. This research considers that addition of silane coupling agent to epoxy resin hardener may be an alternative to the direct chemical pre-treatment of NF before composites manufacture. The current study indicates that silane-in-hardener can eliminate the pre-treatment of fibres and generates composites with optimum mechanical properties

El género Lysaphidus (Hymenoptera: Braconidae) en la Península Ibérica

The genus Lysaphidus Smith, 1944 (Hymenoptera, Braconidae, Aphidiinae) is recorded for the first time from the Iberian Peninsula represented by two species: L. arvensis Stary, 1960, first record for the Iberian Peninsula, and L. santolinae n. sp., both of them parasitoids of Coloradoa Wilson,1910 genus (Homoptera, Aphididae). The mummies were collected on Santolina chamaecyparissus L. and Santolina rosmarinifolia L. (Asteraceae).Se detecta la presencia del género Lysaphidus Smith, 1944 (Hymenoptera, Braconidae, Aphidiinae) en la Península Ibérica, representado por dos especies, L. arvensis Stary, 1960, nueva cita para la Peninsula Ibérica y L. santolinae n. sp., parasitoides ambos del género Coloradoa Wilson, 1910 (Homoptera, Aphididae), cuyas momias fueron recolectadas sobre Santolina chamaecyparissus L. y Santolina rosmarinifolia L. (Asteraceae)

ANALISIS DEL CRECIMIENTO DE Ananas Comosus (L.) MERR. POR EL METODO DE β-SPLINES

Se realizó un experimento de análisis en crecimiento de piña (Ananas comosus {L.) Merr.) cv. 'Española Roja', sembrada en una finca de los aledaños de Jusepín, Edo. Monagas. Se cosecharon mensualmente, al azar, 1 O muestras de la fitomasa de la comunidad y se separaron el follaje asimilatorio y no asimilatorio, los tallos, las raíces, los retoños axilares, el tejido precursor de la inflorescencia, los hijos basales, la corona y los hijos de la corona, el pedúnculo y el fruto. Se secaron las muestras en una estufa a 85"C hasta peso constante. Se midió el área foliar y se procesaron las características de crecimiento de las plantas de piña a partir de los datos primarios de peso seco y área foliar de las muestras, mediante las técnicas de análisis funcional de crecimiento de Hunt. El peso seco total de la planta de piña a los 600días después de la siembra (DDS) fue de 3.940 g m-2, de los cuales 53 % correspondieron a follaje asimilatorio y 2 % a follaje nó asimilatorio. El resto (45%) estuvo representado por el peso seco de tallos, de raíces, de hijos y de otras estructuras. El peso promedio de los frutos frescos (sin corona ni hijos) fue 1.050 g con un rendimiento promedio de 35,03 tm ha-1 de frutos. El índice de área foliar asimilatoria (IAF) máximo fue de 8,14 m2m-2 (96 %) y el de no asimilatorio 0,30 m2m-2 (4 %) a los 600 DDS. Para esa misma fecha las mayores tasasabsolutas (C) y relativa de crecimiento del peso seco total (1RCW) fueron de 33,8 g m -2 d -1 y de o, 02 g g- ld-1 respectivamente. La tasa neta de asimilación (INA) mostró valores amplios de varianza durante el ciclo general del cultivo y la variación del cociente de superficie foliar (CAF) no fue significativamente diferente.   PALABRAS CLAVES: Anna, CAM, crecimiento.   ABSTRACT   In a field of Spanish red pineapple, ten random samples of phytomass were collected at monthly intervals. The material was separated as to assimilatory and non - assimilatory foliage, stems, roots, axillary shoots, precursor inflorescence tissue, basal shoots, crown and crown shoots, peduncle, and fruil The samples were oven ed at 8511C to constant weighl Leaf area was measured and the growth characteristics of the plants were determined using the primary data on dry matter and leaf area of the samples, using Hunt's technique of functional growth analysis. The total dry matter of a pineapple plant, 600 days post-planting (DDS) was 3.940 gm-2, of which assimilatory foliage constituted 53%, non-assimilatory foliage 2%, while stems, roots, sprouts and other structures represented 45%. The mean fresh weightof pineapple fruits (without crown) was 1.050 g and the mean yield of fruits was 35,03 tm ha-1.Ihe maximan assimilatory leaf area index (LAI) was 8,14 m 2m-2 ( 96% ); non-assimilatory being 0,30 m2 m-2 (4%) at600DDS. Atthe samedate, thehighestabsolute (C) and relative cates of  wth of total dry mass (TRCW) were 33,8 gm- d-1 and 0,02 gg- 1d-1 respectively. The net rate of assimilation (INA) showed wide variance values during the general growing cycle; the variation of foliage surface coefficient (CAF) was not significant.   KEY WORDS: Ananas, CAM, growth

Sustainable Manufacture of Natural Fibre Reinforced Epoxy Resin Composites with Coupling Agent in the Hardener

Lignocellulosic natural fibres are hydrophilic, while many matrix systems for composites are hydrophobic. The achievement of good mechanical properties for natural fibre-reinforced polymer (NFRP) matrix composites relies on good fibre-to-matrix bonding at the interface. The reinforcement is normally coated with an amphiphilic coupling agent to promote a strong interface. A novel alternative approach is to dissolve the coupling agent in the hardener for the resin before creating the stoichiometric mix with the base epoxy resin. During composite manufacture, the hydrophilic (polar) end of the coupling agent migrates to surfaces (internal interfaces) and bonds to the fibres. The hydrophobic (non-polar) end of the coupling agent remains embedded in the mixed resin. Mechanical testing of composite samples showed that silane added directly to the matrix produced a NFRP composite with enhanced longitudinal properties. As pre-process fibre coating is no longer required, there are economic (shorter process times), environmental (elimination of contaminated solvents) and social (reduced worker exposure to chemical vapours) benefits arising from the new technique

Supervision multidistribuida de un secadero solar de madera empleando sensores de bajo coste

Multi-distributed supervision of wood in solar dryers is carried out by means of high performance low cost ambient sensors. An experimental dryer of 0.3 m 3 is used for testing the proposed instrumentation mainly based on thermocouples and SENSIRION TM which are combined with the psychometric model defined by ASABE in order to assess the amount of water released by the wood during the drying process. Continuous monitoring enables the Implementation of automated control of the dryer by means of regulating the fan speed and the amount of re-circulated air