Search results for "fibre"
showing 4 items of 494 documents
Electrical conductivity of glass fiber-reinforced plastic with nanomodified matrix for damage diagnostic
2021
The electrical conductivity of glass fiber-reinforced plastic (GFRP) with epoxy matrix modified by multiwall carbon nanotubes (MWCNT) was studied. The electrical conductivity of nanomodified lamina and multi-layered GFRP was investigated on several levels using a structural approach. Components of the electrical conductivity tensor for unidirectional-reinforced monolayer were calculated similarly as in micromechanics using the conductivity of the nanomodified matrix. The electrical conductivity of multilayer composite was calculated using laminate theory and compared with values measured experimentally for various fiber orientation angles. Calculated and experimental data were in good agree…
Modelling and analysing oriented fibrous structures
2014
Abstract. A mathematical model for fibrous structures using a direction dependent scaling law is presented. The orientation of fibrous nets (e.g. paper) is analysed with a method based on the curvelet transform. The curvelet-based orientation analysis has been tested successfully on real data from paper samples: the major directions of fibrefibre orientation can apparently be recovered. Similar results are achieved in tests on data simulated by the new model, allowing a comparison with ground truth. peerReviewed
Characterization of three-dimensional microstructure of composite materials by X-ray tomography
2016
Analysis methods for X-ray microtomographic images of short fibre composite materials were developed. The methods enable estimation of microstructural properties of the material, e.g., aspect ratio and orientation of fibres. Being based on X-ray microtomography and image analysis, the methods are nondestructive and do not require user intervention. In particular, a method for determination of the aspect ratio of fibres was first developed. The method contains an assumption about similarity of the shape of the fibres. The assumption was relaxed in an improved method that can estimate cross-sectional properties of fibres, too, e.g., cross-sectional area. Additionally, the effect of finite ima…
Grain Composition and Functional Ingredients of Barley Varieties Created in Latvia
2015
Abstract Cereals, including barley, have been recognised as functional foods that provide beneficial effect on the health of the consumer and decrease the risk of various diseases. The aim of investigation was to determine the grain composition of barley varieties and perspective breeding lines bred in Latvia and to evaluate its functional ingredients. The results of analysis showed that protein content among varieties ranged from 106.6-146.8 g·kg-1, total dietary fibre 187.4-208.2 g·kg-1, β-glucans 42.8 g-49.4 g·kg-1, and amount of α-tocopherol 6.03-8.93 mg·kg-1. The sum of essential amino acids in barley grain samples was from 32.90 g·kg-1 to 38.71 g·kg-1. All varieties of hulled and hull…