Compressive and Tensile Behaviours of PLLA Matrix Composites Reinforced with Randomly Dispersed Flax Fibres

Nowadays, the ecological footprint of a material is becoming tremendously important. The Poly l-Lactide Acid (PLLA) matrix composites reinforced by randomly scattered flax fibres have mechanical properties similar to polyester/glass composites [1], lower environmental impacts and can be compost at the end of their lives. In this study, the mechanical characterization of biocomposites has been pushed further with the determination of the compressive and tensile properties. Furthermore, the mechanical properties of single flax fibres have been measured and implemented in a micro-mechanical estimation of the composite elastic modulus. Tensile and compressive stiffness determined by the mechanical analyses show very good correlations with the mathematical estimation.     

A Multiplicative Model for Gauge R & R Studies

We introduce a multiplicative measurement error model and analyze a gauge R & R study with the new model using data from a sample exchange program. Some aspects of designing a gauge R & R study are considered. Also, we analyze data from a factorial experiment where the measurement error arises from the new model using a simultaneous analysis of experimental and gauge R & R study data. WinBUGS code for these analyses is provided. Copyright © 2014 John Wiley & Sons, Ltd.     

1.8-THz bandwidth, zero-frequency error, tunable optical combgenerator for DWDM applications

We report on the experimental realization of a simple optical comb generator, based on phase modulation within an amplified fiber loop, which offers exact referencing to an arbitrary supplied reference frequency and tunable comb-line spacing. At a reference wavelength of 1529 nm up to 103 comb lines within a 40-dB power envelope were generated with spacings adjustable from 1 to 25 GHz, limited only by the bandwidth of the phase modulator     

Das Pergamentpapier des Handels

Ohne ZusammenfassungMitteilung aus dem Laboratorium der Veruchsstation und Lehranstalt für Molkereiwesen in Kiel. Referent: A. Burr.     

Nutritional epidemiology

Epidemiological techniques constitute an important method of nutritional investigation. Historical and geographical evidence suggests hypotheses which can be tested by more detailed studies. Cross-sectional surveys describe populations and provide information about prevalence; they also enable the interrelationships of various nutritional and physiological indices to be investigated. The case-control study is useful in exploring possible aetiological factors in diseases, but has the drawback that past dietary information is difficult to obtain accurately. Prospective studies identify predictors of disease and death; they are especially valuable in elucidating the natural history of disease, and supply good evidence on causation, but their duration and expense are disincentives to their use. Randomized controlled trials provide the most precise evidence about causation, and should be used whenever feasible to answer specific questions.     

Sheet molding compound characterization using spiral flow

Sheet molding compound (SMC) is a fiber‐reinforced polymeric composite. It is often used in automotive, marine, and industrial applications over other materials because of its high strength to density ratio, resistance to corrosion, and low cost. There is a demand in the SMC industry to be able to characterize SMC processability. This is particularly true for heavy truck body panels, one of the fastest growing applications of SMC. Because of their large size and high strength requirement, the molding forces have a major influence in the molding cycle. Also because of the long flow paths involved, the ability of the paste to carry glass needs to be properly characterized when developing new SMC materials. In this article, we demonstrate the benefits of using spiral flow as a processability tester. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008