Use Of Cork Research Articles

Effects of dominant tree species on insectivorous birds breeding in Mediterranean oak woodlands

Capsule Differences in Cork Oak Quercus suber and Holm Oak Quercus rotundifolia dominance had little influence on bird communities though bark-gleaners showed a foraging preference for Cork Oak.Aims Examine the use of Cork and Holm Oak trees by insectivorous birds in Mediterranean oak woodlands.Methods Point-counts were used to compare species abundance among Cork Oak-dominated, Holm Oak-dominated and mixed woodlands. Focal foraging observations were used to evaluate the use of Cork and Holm Oaks in the three habitats and to relate tree characteristics with the foraging time of foliage- and bark-gleaners.Results Bird densities in the three habitats were not different for most foliage- and bark-gleaners. Tree preference index values and foraging time per tree showed no significant differences between tree species and foraging guilds, however bark-gleaners had positive index values for Cork Oak in the three habitats. The foraging time of foliage- and bark-gleaners on both tree species showed a positive relationship with characteristics associated with arthropod abundance.Conclusion Cork and Holm Oak trees are equally preferred by foliage-gleaners but bark-gleaners moderately preferred Cork Oak. Characteristics regarding morphology, phenology and physiological condition of trees can be used to predict habitat quality for insectivorous forest birds in Mediterranean oak woodlands.

A novel approach to bar adsorptive microextraction: Cork as extractor phase for determination of benzophenone, triclocarban and parabens in aqueous samples

This study describes the use of cork as a new coating for bar adsorptive microextraction (BAμE) and its application in determining benzophenone, triclocarban and parabens in aqueous samples by HPLC–DAD. In this study bars with 7.5 and 15 mm of length were used. The extraction and liquid desorption steps for BAμE were optimized employing multivariate and univariate procedures. The desorption time and solvent used for liquid desorption were optimized by univariate and multivariate studies, respectively. For the extraction step the sample pH was optimized by univariate experiments while the parameters extraction time and ionic strength were evaluated using the Doehlert design. The optimum extraction conditions were sample pH 5.5, NaCl concentration 25% and extraction time 90 min. Liquid desorption was carried out for 30 min with 250 μL (bar length of 15 mm) or 100 μL (bar length of 7.5 mm) of ACN:MeOH (50:50, v/v). The quantification limits varied between 1.6 and 20 μg L−1 (bar length of 15 mm) and 0.64 and 8 μg L−1 (bar length of 7.5 mm). The linear correlation coefficients were higher than 0.98 for both bars. The method with 7.5 mm bar length showed recovery values between 65 and 123%. The bar-to-bar reproducibility and the repeatability were lower than 13% (n = 2) and 14% (n = 3), respectively.

Cork: a strategic material.

Cork: a strategic material.

Integrated environmental analysis of the main cork products in southern Europe (Catalonia – Spain)

Abstract This study presents an environmental analysis of the cork sector by integrating and evaluating the production of the products that are most commonly made of cork: natural cork stoppers, champagne cork stoppers, white cork granulate and black cork granulate, in order to propose environmental strategies that could contribute to minimising the potential impacts of the cork sector. Life Cycle Assessment (LCA) was the methodology used in order to assess the potential environmental impacts of the cork sector and its main products. Inventory was supported by 15 companies in Catalonia. Different environmental midpoint impact categories were reported and analysed according to CML 2001 method such as Abiotic Depletion (ADP), Acidification Potential (AP), Eutrophication Potential (EP), and many other. Also, the Global Warming Potential (GWP 100 years), was assessed, and it was found that the cork sector contributed to fixing carbon dioxide and consequently can help to mitigate climate change, besides generating cork products. Specifically, 3.4 tonnes of CO2 eq. were emitted to convert a tonne of raw cork from the forest into products, while 18 tonnes of CO2 are fixed per tonne as a result of the existence of cork oak forests; the resulting balance was that 14.6 tonnes of CO2 are fixed. A sensitivity analysis was carried out of the distribution of environmental impacts between products; it was observed that allocation rules were an important point of the assessment. The use of cork, a natural, renewable and local material, can help to reduce the environmental impact of products. The use of cork stoppers contributes to reducing the carbon footprint of beverages such as wines, champagnes, beers, ciders, brandies and many other beverages.

Use of cork agglomerates as acoustic absorbents

Black agglomerate (BA) and composite agglomerate (CA) of cork were tested as acoustic absorbents. The energy absorption coefficient was studied as a function of the specimen thickness. For CA, the effects on the acoustic absorption of the particle size and the resin dosage used in its preparation were also analysed. The wave ratio n, the coefficient of acoustic absorption α and the coefficient of noise reduction (CNR) were calculated using an ASTM norm (C-384-56). Usually, regardless of the specimen thickness, for both BA and CA, α first increased with frequency and then decreased. The maximum of α shifted to a higher frequency with decreasing specimen thickness. In general, BA was the best acoustic absorbent at low and high frequencies, whereas CA was at intermediate frequencies. Particle size and resin dosage had a less important influence on the absorbent behaviour of CA.

Dynamic crushing behaviour of aluminium tubes filled with cork

Cork is a natural cellular material with unique remarkable properties such as low density, great elasticity, chemical stability and resilience, no permeability to liquid and gases and resistance to wear and fire. Besides, it is ecological, hygienic, easy to maintain and a very durable material. Unfortunately, there are still application fields that have not been explored yet for the use of cork, possibly due to the fact that it is a complex cellular material, characterized by very variable mechanical properties which clearly depend on its microstructure. The fundamental aspects of the static and dynamic mechanical behaviour of natural and agglomerate cork, used alone and as filler inside a tube with small dimensions, under axial compressive loading, have already been studied by the authors. Aluminium cork-filled tubes and their empty counterparts were tested experimentally and numerically at quasi-static and dynamic strain rates from 10 -3 s -1 to 600 s -1 . Data from the Split-Hopkinson Pressure Bar and deconvolution techniques were used to generate stress-strain curves for the structures composed of natural and agglomerate cork. The numerical simulations of the dynamic compression of the specimens were carried out using the finite element method software LS-DYNA and showed quite good agreement with the experimental results. Hence, in this work, in order to extend the study started previously and investigate the possible advantages of cork-filling in longer tubes with a different section, the authors simulate, using the same software, the influence of the introduction of agglomerate cork in square and circular aluminium tubes with a diameter/width of 80 mm, a length of 300mm and a variable thickness. The mechanical properties of the structures composed of cork may constitute a potential for this material to be used in innovative applications related to diverse fields such as automotive, transport, ships and military applications.

GC−MS Study of Volatiles of Normal and Microbiologically Attacked Cork fromQuercus suberL.

The volatile compounds of cork were studied by gas chromatography and combined gas chromatography−high-resolution mass spectrometry using simultaneous distillation−extraction to prepare the samples. To assess the origin of the volatiles, three different types of samples were analyzed: “normal”, attacked by Armillaria mellea, and infested by molds. The study of the volatiles of these different types of corks allowed the identification of the chemical modifications which may occur in cork polymers. The cork attacked by A. mellea showed higher amounts of phenols, vanillin, benzaldehyde, benzyl alcohol, and chlorinated compounds than normal cork; this may indicate lignin degradation. The cork infested by molds contained higher levels of 3-methyl-1-butanol, 1-octen-3-ol, 1-octanol, 2-methylisoborneol, chlorinated compounds, and methyl ketones. These components resulting from microbial metabolism were also present in cork attacked by A. mellea. The use of cork attacked by A. mellea is not recommended in the ma...