Polypropylene Fiber Reinforced Polymer Concrete: effect of gamma radiation

Design of polymer concrete involves extensive studies on their materials in order to get improved properties; specifically on the physicochemical properties of both polymer resin and mineral aggregates, including size and shape of the last one. Alternative studies are focusing on using different materials or methods to obtain such improvements. In this work, polymer concrete was elaborated with unsaturated polyester resin, marble particles and polypropylene fibres, after it was modified by using gamma radiation to achieve a complete polymerization. The results show improvements in the compressive strength and in the modulus of elasticity with 0.2 vol.% of polypropylene fibres and irradiation at a dose of 250 KGy. However, lower compressive strains were obtained when using gamma radiation

Degeneración de los folículos postovulatorios en la anchoa del golfo de Vizcaya (Engraulis encrasicolus L.)

The degeneration of postovulatory follicles (POFs) in time and at different temperatures was studied for the Bay of Biscay anchovy. For this purpose a key of 7 POF stages, solely defined on the basis of their histological degeneration characteristics, was applied. The novelty of this procedure is that it separates staging of POFs from their ageing process. The female gonads, taken from several captivity experiments and field samples, were classified in this way. Water temperature in captivity tanks corresponded to high values (17-21°C), except for one case in which different day and night temperatures were applied. In addition, 472 field samples (11948 anchovy females) from several cruises were examined; of these, 126 samples (3348 females) were identified as coming from areas of high sea surface temperature (weighted mean =17.76°C, s.d.=0.84) and 131 samples (3181 females) as coming from areas of low sea surface temperature (weighted mean =14.42°C, s.d.=0.75). There was close agreement in the succession of POF stages over time after spawning between the experiment and the field samples. The first four stages of POF degeneration occurred in less than 24 h, and by the end of the first day the POFs were mainly in Stage V. Stages VI and VII showed their highest occurrence during the first and second half of the second day after spawning, respectively. Full resorption of POFs was achieved in about 55-60 h. For the range of temperatures examined (13-19°C), little effect of temperature on the degeneration of POFs over time was noticed. The advanced degeneration stages were found all day round, showing some overlapping periods when successive spawning cohorts co-occurred. The application of these results for ageing POFs is discussed.Se ha estudiado la degeneración de los folículos postovulatorios (FPOs) para la anchoa del golfo de Vizcaya en el tiempo y a diferentes temperaturas. Para este fin se ha utilizado una clave de 7 estadios de FPOs basada únicamente en características de degeneración histológica. La novedad de este procedimiento consiste en la separación entre la clasificación de los estadios de FPOs y su datación. Así, se han clasificado las gónadas de hembras obtenidas a partir de experimentos en cautividad y de muestras de campo. Las temperaturas de los experimentos en cautividad se corresponden con temperaturas altas (17-21ºC), excepto en un caso en el que se aplicaron cambios de temperatura día/noche. Además se clasificaron gónadas de anchoa de 472 muestras de diferentes campañas (11948 hembras de anchoa). De éstas, 126 muestras (3348 hembras) fueron identificadas como procedentes de zonas con temperatura superficial alta (media ponderada =17.76ºC, s.d.=0.84) mientras que 131 muestras (3181 hembras) procedían de zonas con temperaturas superficiales bajas (media ponderada =14.42ºC, s.d.=0.75). Se ha encontrado una gran concordancia en la sucesión temporal de los estadios de FPOs tanto en los experimentos como en las muestras de campo. Los 4 primeros estadios de degeneración de FPOs ocurren en menos de 24 horas y para el final del primer día se alcanza mayoritariamente el estadio V. Los estadios VI y VII son mayoritarios durante la primera y segunda mitad del segundo día tras la puesta, respectivamente. La reabsorción total del folículo se produce en unas 55-60 horas. Para el rango de temperaturas examinado (13-19ºC), la influencia de la temperatura en la degeneración de los FPOs resulta pequeña. Los estadios de degeneración avanzada se encuentran a lo largo de todo el día, mostrando periodos de superposición de cohortes sucesivas. Finamente se discute la aplicación de estos resultados a la datación de los FPOs

Influence of 1D and 2D carbon fillers and their functionalisation on crystallisation and thermomechanical properties of injection moulded nylon 6,6 nanocomposites

Carbon nanotubes (CNTs) and graphene were used as reinforcing fillers in nylon 6,6 in order to obtain nanocomposites by using an injection moulding process. The two differently structured nanofillers were used in their pristine or reduced form, after oxidation treatment and after amino functionalisation.Three low nanofiller contents were employed. Crystallisation behaviour and perfection of nylon 6,6 crystals were determined by differential scanning calorimetry and wide angle X-ray diffraction, respectively. Crystallinity was slightly enhanced in most samples as the content of the nanofillers was increased. The dimensionality of the materials was found to provide different interfaces and therefore different features in the nylon 6,6 crystal growth resulting in improved crystal perfection. Dynamical, mechanical analysis showed the maximum increases provided by the two nanostructures correspond to the addition of 0.1 wt.% amino functionalised CNTs, enhancing in 30% the storage modulus and the incorporation of 0.5 wt.% of graphene oxide caused an increase of 44% in this property. The latter also provided better thermal stability when compared to pure nylon 6,6 under inert conditions. The superior properties of graphene nanocomposites were attributed to the larger surface area of the two-dimensional graphene compared to the one-dimensional CNTs

Efeitos de snack de amaranto desengordurado (Amaranthus caudatus L.) no metabolismo lipídico de pacientes com hipercolesterolemia moderada

We evaluated the effects of defatted amaranth (Amaranthus caudatus L.) snacks on plasma lipids in moderate hypercholesterolemic patients. Twenty-two subjects [30-65 years old), 11 males, with total cholesterol (TC) &gt; 240 mg.dL-1, low-density cholesterol (LDL-c) 160-190 mg.dL-1 and plasma triglycerides (TG) < 400 mg.dL-1] were randomized in a double blind clinical trial to receive an amaranth snack (50 g/day) or equivalent corn snack (placebo) for 2 months. There were no differences between amaranth and placebo on TC and LDL-c, and TG respectively: -8.4 and -5.7% (p = 0.17); -12.3 and -9.7% (p = 0.41) and -0.6 and -7.3% (p = 0.47). However, amaranth snacks significantly reduced high-density cholesterol (HDL-c): -15.2 vs. -4% (p = 0.03). In conclusion, the intake of 50 g of extruded amaranth daily during 60 days did not significantly reduce LDL-c in moderate hypercholesterolemic subjects; furthermore there was a significant reduction in HDL-c. Studies with greater number of subjects and greater quantity of this food are necessary to test the effects of amaranth on lipid metabolism in humans.Avaliamos os efeitos de snacks feitos com amaranto desengordurado (Amaranthus caudatus L.) no metabolismo lipídico de pacientes com hipercolesterolemia moderada. O ensaio clínico contou com vinte e dois voluntários [30-65 anos, 11 homens, com colesterol total &gt; 240 mg.dL-1, LDL-c 160-190 mg.mL-1, e triglicerídeos plasmáticos (TG) < 400 mg.mL-1] aleatoriamente distribuídos em dois grupos que receberam um snack de amaranto (50 g/dia) ou um placebo equivalente (snack de milho) por dois meses. Não houve diferenças significativas entre o amaranto e o placebo no colesterol total, LDL-c e TG, cujos valores foram, respectivamente, -8,4 e -5,7% (p = 0,17); -12,3 e -9,7% (p = 0,41) e -0,6 e -7,3% (p = 0,47). Entretanto, o consumo de snacks de amaranto reduziu significativamente o HDL-c: -15,2 vs. -4% (p = 0,03). Concluímos que o consumo de 50 g de amaranto extrusado por 60 dias não foi suficiente para reduzir significativamente LDL-c em pacientes com hipercolesterolemia moderada; além disso, observou-se significativa redução de HDL-c. Estudos com maior número de participantes e maior quantidade de amaranto são necessários para se testarem os seus efeitos no metabolismo humano.FAPESPInCorCNP

SAVASA project @ TRECVID 2012: interactive surveillance event detection

In this paper we describe our participation in the interactive surveillance event detection task at TRECVid 2012. The system we developed was comprised of individual classifiers brought together behind a simple video search interface that enabled users to select relevant segments based on down~sampled animated gifs. Two types of user -- `experts' and `end users' -- performed the evaluations. Due to time constraints we focussed on three events -- ObjectPut, PersonRuns and Pointing -- and two of the five available cameras (1 and 3). Results from the interactive runs as well as discussion of the performance of the underlying retrospective classifiers are presented

Influence of Silanization Treatment on Thermomechanical Properties of Multiwalled Carbon Nanotubes: Poly(methylmethacrylate) Nanocomposites

Unfunctionalized and silanized multiwalled carbon nanotubes (MWNTs) were incorporated in poly(methylmethacrylate) matrices using in situ polymerization. Polymer-compatible functional groups on carbon nanotube (CNT) surfaces were characterized by infrared spectroscopy. These chemical moieties improve interaction at interfaces, allowing transfer of mechanical load between the matrix and the dispersed phase as reflected in the resulting improved mechanical and thermophysical properties. The composites were characterized by Raman spectroscopy to evaluate molecular level interactions and dynamical mechanical analysis. Composites with silanized CNTs have higher storage modulus (E′) than polymer reinforced with unfunctionalized nanotubes. Considering the average of the samples, only 1 wt.% of silanized nanotubes provides an increase in E′ of 165% at room temperature with respect to polymer matrix, and the increments reached are by a factor of 6.8 and 13.6 over the polymer matrix at 80°C and 90°C, respectively. 1 wt% of silanized CNTs increases the glass transition temperature of polymer matrix around 30°C. Microscratch testing results of composites show that unfunctionalized CNTs cause deeper penetration of the indenter than polymer matrix at the same force; however, the composites developed with silanized CNTs present more regular behavior than polymer reinforced with unfunctionalized CNTs

A technical and environmental comparison of novel silica PEI adsorbent-based and conventional MEA-based CO2 capture technologies in the selected cement plant

The cement industry accounts for almost 7 % of anthropogenic carbon dioxide emissions globally. Therefore, it is imperative to identify innovative solutions to mitigate carbon dioxide emissions from the cement industry.This study aims to evaluate and compare the technical and environmental aspects of integrating two post combustion carbon capture processes (CCS) into a cement plant: the conventional monoethanolamine (MEA)-based CCS process and the novel silica-alkoxylated polyethyleneimine (SPEI)-based CCS process. Three scenarios were considered: (i) a reference cement plant without CCS, (ii) the conventional MEA-based CCS system integrated into a cement plant and (iii) the novel SPEI-based CCS system integrated into a cement plant. The technical evaluation results showed that the regeneration energy requirements for the conventional MEA and novel SPEI based CCS processes were 3.53 GJ/tonne CO2 and 2.36 GJ/tonne CO2, respectively, to achieve a capture rate of 90 %. However, the performance of MEA-based carbon capture processes can be improved by using advanced amine formulations that offer lower regeneration heat requirements at 3.3 GJ/tonne CO2, although this is still higher than the SPEI-based carbon capture processes.The novel SPEI-based CCS process showed superior environmental performance compared to the conventional MEA-based CCS process. The endpoint single score was conducted which showed that the SPEI-based CCS process had a lower impact on human health, ecosystems, and resources (7 %, 9 %, and 26 % lower, respectively) compared to the MEA-based CCS process.<br/