Search results for " wood"
showing 10 items of 239 documents
Supply and uses of wood in Auvergne, from the Iron Age in the Middle Ages
2018
Waterlogged woods are rare discoveries in archeology because of the conditions inherent in their conservation. When they reach us, they give a lot of data on the importance of this material for past populations.Auvergne is a privileged context for their conservation. Thousands of woods from fortuitous discoveries or archaeological excavations are dated from the Neolithic to the modern era, however the corpus covers mostly the Second Iron Age until the Middle Ages.The diversity of the woods enables a better understanding of different uses according to their respective destination.The state of conservation of many elements gives information about the different stages of shaping, from the fell…
What do we know about growth of vessel elements of secondary xylem in woody plants?
2021
Despite extensive knowledge about vessel element growth and the determination of the axial course of vessels, these processes are still not fully understood. They are usually explained as resulting primarily from hormonal regulation in stems. This review focuses on an increasingly discussed aspect - mechanical conditions in the vascular cambium. Mechanical conditions in cambial tissue are important for the growth of vessel elements, as well as other cambial derivatives. In relation to the type of stress acting on cambial cells (compressive versus tensile stress) we: (i) discuss the shape of the enlarging vessel elements observed in anatomical sections; (ii) present hypotheses regarding the …
Neolithic woodland in the north Mediterranean basin: A review on Olea europaea L.
2013
The aim of this paper is to specify the natural distribution of Olea europaea L. during the Early Holocene in the Northern Mediterranean by means of the identification of wood charcoal remains of this species at prehistoric sites. For this purpose, we have reviewed the relevant literature and extracted the data in which Olea charcoal has been identified. We have taken into consideration the biogeographical and chrono-cultural contexts in which the species is present, its frequency of occurrence at different locations and the associated plant taxa with the aim of tracking the Holocene history of the oleaster. Based on this information we suggest that the species started expanding during the …
Thermal conductivity measurement of insulating innovative building materials by hot plate and heat flow meter devices: A Round Robin Test
2019
Abstract The characterization of thermal insulation properties of construction materials represents a fundamental step on the building insulation assessment. In recent years innovative materials have been introduced in the market to fulfill the continuously growing requirements of energy saving and sustainability, and their performance is not so reliable and mature as it happens for traditional insulators. The work presents a Round Robin Test realised among six European laboratories hosting hot plates devices to measure the thermal conductivity of four different materials: aerogel, vacuum insulation panels, polystyrene and birch wood fibre insulation boards. After the definition of the comm…
I Ventimiglia e le arti decorative a Lascari
2016
Il saggio, attraverso l'analisi di inedite fonti archivistiche, delinea la committenza di alcuni membri della famiglia Ventimiglia per Lascari e la sua chiesa parrocchiale dalla fine del XVII secolo ai primi decenni del XIX. Gli esponenti della nobile stirpe per la realizzazione di tali opere, alcune delle quali ancora custodite, si rivolgevano perlopiù ad artisti palermitani, tra cui l'abile marmorario Domenico Magri. The essay, through the analysis of unpublished archival sources, outlines the patronage of some members of the Ventimiglia family for Lascari and its parish church from the end of the 17th century to the first decades of the 19th century. The exponents of the noble lineage fo…
Nitrogen Distribution in Annual Growth of ‘Italia’ Table Grape Vines
2018
Little information is available about either nitrogen (N) content/concentration in table grape vines. The knowledge about N accumulated by the vine organs during the season could support sustainable fertilization programs for table grape vineyards. The aim of the present paper was to investigate the N content in different annual organs, in summer and winter pruning materials, clusters at harvest and fallen leaves at post-harvest of table grape vines in order to verify the vine annual N requirements to be used for sustainable N fertilization schedules. Biomass and nitrogen were analyzed at six phenological growth stages (flowering, berry-set, berry growth, veraison, ripening, and harvest) fr…
Issues Related to the Restoration of Mirrors of the Wooden paliotto della chiesa del Santissimo Crocifisso all’Albergheria, Sicily (Italy)
2017
ABSTRACTIn this work, the decision-making process involved in the restoration of the eighteenth century paliotto ligneo (wooden altar frontal) della chiesa del Santissimo Crocifisso all’Albergheria of Palermo is presented. Earlier research concerning mirror restoration was based on only a few case studies and the proposed techniques were not suitable for the artwork here. As a consequence, it was necessary to re-examine theories and protocols of modern restoration to plan an appropriate intervention of the altar frontal. Since in this artwork the role of mirrors is not to give back images, as usual, but rather to create special light effects and play of lights, this work aims to find an app…
Consolidation of waterlogged woods by in-situ polymerisation of isoeugenol
2008
Architetture lignee per lo spettacolo tra XVII e XVIII secolo a Palermo (Theatral wooden architectures in Palermo during XVIII and XIX centuries)
2016
La realizzazione di architetture per lo spettacolo, stabili o temporanee, interamente realizzate in legno fu una consuetudine sette-ottocentesca diffusa sia in molte grandi città europee sia in centri di minori. Anche a Palermo anfiteatri, teatri-circo e casotti occuparono anche a lungo le piazze del centro storico e grandi edifici "contenitori" pubblici o di facoltosi cittadini, ospitando giochi equestri, spettacoli con animali esotici. La connotazione temporanea suggeriva l'uso del legno a costruttori e progettisti: realizzate rapidamente, potevano con semplicità essere smontate e riproposte altrove. Sebbene si trattasse di "architetture provvisorie", era necessario che fossero non solo s…
Bio-inspired consolidants derived from crystalline nanocellulose for decayed wood
2018
Abstract Novel bio-inspired materials derived from crystalline nanocellulose (CNC) have been tested as wood consolidants. A suspension of CNC, produced by acid hydrolysis of cellulose and used as such or mixed with lignin and/or siloxane derivatives (PDMS), was applied on rotted wood samples of Norway spruce. X-Ray diffraction analysis on CNC powder showed high crystallinity index. Dynamic light scattering (DLS) measurement indicated a nearly uniform particle size distribution with an average hydrodynamic diameter for pure CNC smaller than that in the mixtures. Raman and FTIR spectroscopies suggested interactions between lignin, PDMS and CNC components. The storage modulus of wood samples, …