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This paper describes a study of layered polymers with the addition of reinforcing fibres. Their advantages are strength and stiffness, lightness and improved chemical resistance. The study deals with a comparative evaluation of the wear resistance of textolite with different reinforcing fibres under sliding friction conditions. A sample of the investigated material, made in the form of a disc, was fixed in the centre of the table surface and driven into rotational motion at a given frequency. A 6 mm diameter ball made of 100 Cr6 steel was used as a control sample, which was rigidly fixed in the end of a cylindrical pin (indenter). A normalised normal load was applied to the indenter, which was resting on the disc at some distance from the centre of rotation. During the tests, the coefficient of friction and the depth of penetration of the ball into the test sample were continuously measured. The tests were carried out with increasing and decreasing of the load with the interval of 2,0 N. The duration of the long-term wear tests for each sample was 21500 m of friction path (about 20 hours). The estimation of fixed changes of the friction coefficient from load at tests on wearability of couplings has been carried out. The results of tests of the investigated materials samples have shown the best indices on the intensity of wear at mating with a sample from textolite PTG compared to oxafen and Kevlar, accordingly, in 2.97 and 5.93 times.

A method to increase the protein content of sunflower meal was developed that uses a combination of milling, sieving and gravity tables to separate fractions with higher and lower protein content. The investigation allowed to compare different mills' ability to break down the lumps of raw sunflower meal and allow a suitable mechanical separation with sieving and gravity separation. Different settings of the mills were tested with or without material pre-sieving. Sieve mesh sizes were investigated in the range 250 to 500 mm that allowed the production of high protein fine material and a good performance of the gravity table separation. Sunflower meal was successfully enriched in protein to a level similar to low protein soybean meal by utilising the process described in this work. In particular proteins were increased on average by 7% to a level of 43.5%. The yield of the separation can justify industrial applications of this process whereby the high protein material can have a potential use in feed and food formulations. [ABSTRACT FROM AUTHOR]

Le chanvre industriel est cultivé sur des surfaces limitées (surfaces proches de 11 000 ha en France en 2014, source CETIOM), mais comme pour toute espèce cultivée, une activité de sélection est nécessaire. Celle-ci est conduite en France par un acteur unique depuis plusieurs dizaines d’années, la Fédération Nationale des Producteurs de Chanvre (FNPC). Cet article présente les différents critères de sélection actuels et à venir. Certains axes historiques sont toujours travaillés aujourd’hui, comme la teneur en Δ9-tétrahydrocannabinol, dans un souci de respect des réglementations, ou le maintien de l’état monoïque, permettant une culture mécanisée. D’autres critères de sélection ont évolué, en particulier la précocité variétale et le rendement paille. Pour ces deux critères, de nouveaux objectifs sont apparus : pour la précocité variétale, l’équipe de sélection cherche à élargir la gamme existante, quant au rendement paille, le but actuel est d’améliorer la productivité de la plante, c’est-à-dire d’augmenter le rendement à précocité constante. Enfin, de nouveaux axes de sélection apparaissent, comme par exemple la facilité de défibrage et la tolérance à l’orobanche.

The French branch of industrial hemp: macroeconomics insights. The branch of industrial hemp is of low economic dimension, without being in the field of microeconomics. Supplying fibres, plant aggregates (shives), oilseeds and proteins. The branch has had historically to separate itself from its cousin, the drug cannabis. Although small, its economical dimension is from regional to global according to produced materials. This sector is very strongly regulated by its national and European structuring. [ABSTRACT FROM AUTHOR]

The composite fiber materials of polymers (FRP) have physical properties, which are exploited recently for the reinforcement and rehabilitation of the structures, in mechanical, civil engineering and biomedical field, subjected to degradation or default risks. Since a beam without any form of reinforcement will fail when subjected to a relatively small tensile load. Therefore the use of the FRP to strengthen the structures is an effective solution to increase the overall strength technique. In this paper, a new theoretical approach model to estimate shear and peel-off stresses is proposed. Axial stresses and bending moment coupled with shear deformation and thermal effect in an FRP-strengthened beam are considered, including the variation in FRP plate fiber orientation. [ABSTRACT FROM AUTHOR]