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Sorption and thermodynamic properties of Terminalia superba Engl. & Diels and Triplochiton scleroxylon K. Schum. through the 15, 35 and 50 degrees C sorption isotherms. European Journal of wood and wood products. 72(1 ): 99-106.



Abstract: The hygroscopicity and thermodynamic properties of Terminalia superba Engl. & Diels (limba) and Triplochiton scleroxylon K. Schum. (obeche) wood were studied and the species were compared. The 15, 35 and 50 A degrees C isotherms were plotted by applying the saturated salts method and fitted using the GAB model. The thermodynamic parameters were obtained from the isotherms through the integration method of the Clausius-Clapeyron equation. Infrared spectra were used to study possible chemical modifications in the cell wall, and X-ray diffractograms were used to analyse the crystal structure of the cell wall. Obeche had shorter crystallite length and a lower crystallinity index, giving rise to a higher number of amorphous zones and thus a higher number of sorption sites in the monolayer. As a result, the saturation moisture content in the monolayer (X (m) ) is greater in obeche than in limba. In terms of the thermodynamic properties, in both species the net isosteric heat of sorption decreases as the equilibrium moisture content increases, and more energy is required in desorption than in adsorption.

 

García Fernandez, F.

Esteban, L. G.

de Palacios, P.

Simon, C.

Garcia-Iruela, A.

de la Fuente, J.


2014

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Ronny Rößler , Marc Philippe

Johanna H.A. van Konijnenburg-van Cittert, Stephen McLoughlin, Jakub Sakala , Gea Zijlstra, Rajanikanth Annamraju, Sidney Ash , Pieter Baas

Marion Bamford , Richard Bateman

Menno Booi , Nareerat Boonchai

Mariana Brea , Alexandra Crisafulli

Anne-Laure , Martina Dolezych

Tânia Dutra , Luis G. Esteban

Paula Falaschi, Howard Falcon-Lang , Zhuo Feng , Silvia Gnaedinger

Margot Guerra Sommer, Melise Harland, Rafael Herbst, Jason Hilton, Eugenia Iamandei , Stãnilã Iamandei , Hong-Hen Jiang , Zikun Jiang , Kyungsik Kim , Lutz Kunzmann , Francine Kurzawe, Sheila Merlotti, Brigitte Meyer-Berthaud,

Serge Naugolnykh

Harufumi Nishida, Changhwan Oh, Olga Orlova , Paloma de Palacios, Mike Pole, Imogen Poole, Roberto Pujana, Patricia Ryberg, Jakub Sakala, Rodney Savidge, Stephan Schultka, Herbert Süß, Edith Taylor, Kazuo Terada, Frédéric Thévenard, Teresa Torres, Ezequiel Vera, Elisabeth Wheeler, Xiao-ju Yang, Shaolin Zheng & Wu Zhang.


2014

Which name(s) should be used for Araucaria-like fossil wood?— Results of a poll. Taxon. 63(1): 177-184



Abstract: Araucarioxylon Kraus is a widely known fossil-genus generally applied to woods similar to that of the extant Arau- cariaceae. However, since 1905, several researchers have pointed out that this name is an illegitimate junior nomenclatural synonym. At least four generic names are in current use for fossil wood of this type: Agathoxylon Hartig, Araucarioxylon, Dadoxylon Endl. and Dammaroxylon J.Schultze-Motel. This problem of inconsistent nomenclatural application is compounded by the fact that woods of this type represent a wide range of plants including basal pteridosperms, cordaitaleans, glossopterids, primitive conifers, and araucarian conifers, with a fossil record that extends from the Devonian to Holocene. Conservation of Araucarioxylon has been repeatedly suggested but never officially proposed. Since general use is a strong argument for con- servation, a poll was conducted amongst fossil wood anatomists in order to canvass current and preferred usage. It was found that the community is divided, with about one-fifth recommending retention of the well-known Araucarioxylon, whereas the majority of others advocated use of the legitimate Agathoxylon. The arguments of the various colleagues who answered the poll are synthesized and discussed. There is clearly little support for conservation of Araucarioxylon. A secondary aspect of the poll tackled the issue as to whether Araucaria-like fossil woods should be either gathered into a unique fossil-genus, or whether two fossil-genera should be recognized, based on the respective presence or absence of axial parenchyma. A majority of colleagues favoured having one fossil-genus only. Agathoxylon can be used legitimately and appears to be the most appropriate name for such woods. However, its original diagnosis must be expanded if those woods lacking axial parenchyma are to be included.

 

MATERIALS:

WOOD and PAPER

UNIVERSIDAD POLITÉCNICA DE MADRID © 2017

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Comparative wood anatomy of Juniperus from Macaronesia. IAWA Journal. 35(2):186-198



Abstract: The wood anatomy of the three species of Juniperus occurring in Macaronesia is compared for the first time using representative samples of each species collected in its natural region of provenance: J. cedrus Webb & Berthel and J. phoenicea L. var. canariensis Guyot, in the Canary Islands, and J. brevifolia (Seub.) Antoine, in the Azores. The three species are anatomically similar, although some qualitative differences were observed: distribution of axial parenchyma very scarce in J. phoenicea compared with the other two species, presence of crassulae only in J. phoenicea, presence of torus extensions and notches on pit borders in the radial walls of J. brevifolia, and ray parenchyma end walls slightly nodular in J. cedrus as opposed to very nodular in J. phoenicea and J. brevifolia. In addition, the biometry of tracheid pit diameter in the radial walls, ray height in number of cells, and largest and smallest diameters of cross-field pits shows differences for a significance level of 95%.

 

de Palacios, P.

Esteban, L. G.

García Fernandez, F.

Garcia-Iruela, A.

Conde, M.

Román-Jordán, E.


2014

44

Mendes, M.M.

Dinis, J.

Esteban, L.G.

de Palacios, P.

García-Fernández, F.

Pais, J.


2014

Early Cretaceous woods of Figueira da Foz Formation in western Portugal: Palaeoenviromental, palaeoclimatic and palaeobiogeographic insights. Cretaceous Research. 51:112-120



Abstract: Fossil woods of the genus Protocupressinoxylon Eckhold are reported from the Lower Cretaceous (upper Aptian e lower Albian) of Casal do Estortiga, near Santa Catarina da Serra, Lusitanian Basin, western Portugal. The three silicified specimens show up to 7-mm-thick-walled, rounded to polygonal tracheids; homogeneous rays, separated by 2 e 8 cell rows (in average 3e4); normal or traumatic, diffuse axial parenchyma with abundant cell content; and no resin canal but abundant resin content. The cupressoid conifers dominated the border between the temperate wet tropical belt and the arid mid-latitude belt. The indistinct growth rings suggest no marked seasonality in western Portugal, as it was also suggested in the Iberian Mountain System. Several other climate proxies of the trunk-bearing unit confirm that the wood was deposited under a warm and wet climate. During the Early Cretaceous, the Iberian Peninsula was a connecting bridge between Laurasia and northern Gondwana, acting as a large regional ecotone. Although the Iberian Peninsula was dominated by a Laurasian component, climatic differences between the two regions were driving forces behind biogeographical relationships in the western Tethys.

 

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Wood anatomy of Tetraclinis articulata from its natural distribution area in southeast Spain. IAWA Journal. 35(2):186-198



Abstract: For the first time, the wood anatomy of Tetraclinis articulata (Vahl) Masters has been studied using representative samples from its natural distribution area in Spain, in Sierra de Cartagena (Region of Murcia). Mature wood was collected from five individuals representative of the forest stand and their anatomy was compared with other genera of the Cupressaceae. Axial tracheids without helical thickenings, low homogeneous rays, cupressoid pits and the absence of normal axial resin canals are characteristic features of this monotypic genus, as they are of most other Cupressaceae genera. An obvious warty layer separates this wood from the genera sharing its territory (Cupressus and Juniperus) and its semi-spherical, slightly anastomosed warts distinguish it from other, geographically distant genera (Actinostrobus and Callitris). The presence of traumatic axial resin canals is reported for the first time and supports the occurrence of this feature outside the Pinaceae. The wood anatomical diversity within the clade comprising Tetraclinis, Microbiota and Platycladus, as reconstructed by molecular analysis, is discussed.

 

Esteban, L. G.

de Palacios, P.

Garcia-Iruela, A.

Román-Jordán, E.

García Fernandez, F.

Díaz, S.

Conde, M.


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