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A rather extensive degradation of cellulose and hemicelluloses was found in waterlogged oak wood samples from the ancient warship Vasa by size exclusion chromatography with the solvent system lithium chloride/ N,N-dimethylacetamide (LiCl/DMAc). The degradation has mainly occurred after salvage of the wreck, probably as a consequence of keeping iron contaminated wood in contact with air. The most likely explanation is Fenton type of reactions degrading the wood polymers and oxidising reduced sulphur forms to sulphuric acid. An increased degradation rate of the Vasa wood can be anticipated in the future if the sulphuric acid cannot be neutralised and the oxidative reactions cannot be quenched., QC 20100525

The evolution of almost 40 oak-related volatile compounds and the sensorial characteristics of red wines from four Spanish denominations of origin (DOs) (Bierzo, Toro, Ribera de Duero, and Rioja) during aging in barrels made of Rebollo oak wood, Quercus pyrenaica, were studied and compared to the same wines aged in American and French oak barrels. Each oak wood added unique and special characteristics to the wine, and in addition, each wine showed a different ability to extract the compounds, which result in these characteristics from the oak wood. In general, wines aged in Q. pyrenaica wood were characterized by high levels of eugenol, guaiacol, and other volatile phenols. In regards to compounds like cis-whiskylactone or maltol, the behavior of this wood is very similar to that of American oaks. When considering phenolic aldehydes and ketones, the levels of these compounds are intermediate between those of French and American woods and depend greatly on the type of wine. The type of oak, on the other hand, does not affect the chromatic characteristics of the wines. In sensory analysis, the biggest differences are found in the olfactory phase. Among the four DOs studied, wine aged in Q. pyrenaica presented the highest notes of wood, with more aromas of roasting, toasting, milky coffee, spices, or wine-wood interactions. The wines aged in barrels made of Q. pyrenaica wood were highly regarded, and preference was shown for them over those same wines when they had been aged in barrels of American or French oak. © 2008 American Chemical Society.

The chemical composition of heartwood from the Spanish oaks Quercus petraea and Q. pyrenaica includes a wide range of volatile compound families (volatile phenols, phenolic aldehydes, furanic compounds, lactones, phenyl ketones, and others), which are potentially extracted into wine during aging. Changes in volatiles during the natural seasoning process followed in barrel cooperage were studied. Volatile compounds varied during seasoning, with some increasing in concentration while others decreased or did not show significant variations. The evolution of the wood was most significant during the first two years of seasoning, followed by stabilization during the third year, with variations depending on species, origin, and seasoning environmental conditions. Copyright © 2007 by the American Society for Enology and Viticulture. All rights reserved.

In this paper, the changes in the composition of a red wine obtained from Tempranillo grapes (Vitis vinifera L.), stored from 12 to 24 months in bottles were studied. The wine was previously aging for 21 months in barrels made of Spanish oak wood (Quercus spp.). The changes of chromatic data, global polyphenolic families assessment (polyphenols, catechins, proanthocyanidins and anthocyanins) and individually polyphenols by HPLC during their storage time in bottles were studied and compared with these of the same wine aged in barrels made of French oak and American oak and stored in bottle for 24 months. Samples of wines obtained after 12 months in bottle were also compared with those after 24 months. The stepwise discriminant analysis with data of chromatic parameters and global polyphenolic families indicates that the wines aged in Spanish and French oak wood barrels, after 24 months stored in bottle, have similar characteristics, but they are significantly different to those of wines aged in barrels made of American oak wood. Regarding the analysis of individually non-anthocyanic polyphenols, discriminant analysis shows that wines stored for 24 months in bottle, aged in barrels made of Spanish, French and American oak woods, show overlapping results, while those from wines after 12 months in bottle are more dispersed. The discriminant analysis carried out on anthocyanidin concentrations of wines stored 24 months in bottles has shown three groups according the kind of wood used, indicating that wines aged in Spanish and French oak barrels are much more similar in anthocyanidin concentrations than those aged in the American barrels. © Springer-Verlag 2007.

A red Rioja wine aged for 21 months in barrels made of Spanish oak wood (Quercus spp.), was stored in bottles for 24 months at wine cellar. The evolution of some volatile compounds during their storage time in bottles was studied and compared with the evolution of the same wine, but aged in barrels made of French oak (Q. robur, Q. petraea) and American oak (Q. alba). Although the volatile composition of wine underwent an evolution during bottle aging, this was carried out in such a way that the most important characteristics spread into wine from wood, remained until the end of bottle aging, or at least, for the 24 months of our research. Therefore, wines with different characteristics were obtained from the same wine, after 21 months of aging in barrels and 24 months of aging in bottle, depending on the kind of wood used in oxidative aging. © 2005 Elsevier B.V. All rights reserved.

The need for new sources of quality wood supply for cooperage has led to looking into the possibility of utilizing Quercus pyrenaica Wild. oak, a species native to the Iberian peninsula, as an alternative to other European (Quercus robur and Qurecus petraea) and American (Quercus alba) oaks. The low molecular weight phenolic composition, ellagitannins, and volatile compounds (including a wide range of compound families such as volatile phenols, furanic compounds, lactones, phenyl ketones, other lignin-derived compounds, and volatile compounds related to off-flavors) of green heartwood from Spanish forest regions were studied by HPLC and GC, in order to know its enological characteristics. The chemical composition of Q. pyrenaica is similar to that of other species commonly used in cooperage to make barrels, showing only quantitative differences that were more significant with respect to American than to French species. The four provenance regions studied showed similar chemical composition, with high variability among individuals, often higher than the variability among regions of provenance, but in line with that described in other European and American oak woods. Therefore, this species must be considered to be suitable for aging wine. © 2006 American Chemical Society.

Ancient DNA has received much attention since the mid-1980s, when the first sequence of an extinct animal species was recovered from a museum specimen. Since then, the majority of ancient DNA studies have focused predominantly on animal species, while studies in plant palaeogenetics have been rather limited, with the notable exception of cultivated species found in archaeological sites. Here, we outline the recent developments in the analysis of plant ancient DNA. We emphasize the trend from species identification to population-level investigation and highlight the potential and the difficulties in this field, related to DNA preservation and to risks of contamination. Further efforts towards the analysis of ancient DNA from the abundant store of fossil plant remains should provide new research opportunities in palaeoecology and phylogeography. In particular, intraspecific variation should be considered not only in cultivated plants but also in wild taxa if palaeogenetics is to become a fully emancipated field of plant research.

A red Rioja wine was aged in barrels made of Spanish oak wood for 21 months. The evolutions of colour percentage intensity, families of phenolic compounds and low molecular weight phenolic compounds were studied in these wines and compared with those of the same wine aged in barrels made of French and American oak. The analysis of chromatic parameters and total anthocyanins indicates that the wines aged in Spanish and French oak wood barrels have similar chromatic characteristics, but are significantly different to those of wines aged in barrels made of American oak wood, indicating a different degree of modification of the colour. The ageing process also had an important influence on the low molecular weight polyphenols composition of wine. The evolution of these components allowed the production of wines with different characteristics, in relation to the type of wood used in barrel making process. On the other hand, Spanish oak wood can be considered suitable for barrel production for quality wines, since a wine aged in barrels made of Spanish oak wood showed similar and intermediate characteristics to those of the same wine aged in French and American oak woods.

The evolution of low molecular weight polyphenols in Spanish oak heartwood of Quercus robur, Quercus petraea, Quercus pyrenaica, and Quercus faginea was studied by HPLC, in relation to the processing of wood in barrel cooperage. The polyphenolic composition of Spanish woods subjected to natural seasoning for 3 years and to the toasting process was studied in relation to those of French oak of Q. robur (Limousin) and Q. petraea (Allier) and American oak of Q. alba (Missouri), which are habitually used in cooperage. The concentrations of benzoic and cinnamic acids and aldehydes of Spanish woods increased during seasoning depending on the duration of this process and in the same way as those of French and American woods. The process having the main influence on the phenolic composition of wood was the toasting. It led to high increases in the concentration of phenolic aldehydes and acids, especially cinnamic aldehydes (sinapic and coniferylic aldehydes), followed by benzoic aldehydes (syringaldehyde and vanillin) and benzoic acids (syringic and vanillic acids). This polyphenolic composition in Spanish oak species evolved during toasting as in French and American oak, but quantitative differences were found, which were especially important in American species with respect to the others.

Northern red oak boards, 1 inch thick by 4 inches wide by 24 inches long, were dried from an initial moisture content of approximately 80 percent of various final moisture contents by radiofrequency electrical energy. Drying occurred rapidly above the fiber saturation point, but slowed down considerably below this moisture content. With the drying system used in this investigation, the average moisture content could be reduced in 15 minutes from 80 to 25 percent. However, the level of degrade in boards dried to 25 percent or below was probably too high for many oak products in which honeycomb is an important defect. The results did suggest that radiofrequency drying has some potential as a predrying process to be followed by lower temperature drying. (Author)

The level of mill rejects of furniture cuttings dried noted in this investigation is obviously too high to be tolerable. Crook in the long cuttings and cup in the wide cuttings were the major reasons for rejection. Other shorter and narrower cuttings had a much lower rejection rate--one that probably could be tolerated. Although some end checking occurred, and there was some evidence that end coating would reduce this occurrence, end checking caused no rejections. Other drying defects, such as honeycomb or surface checking, were practically nonexistent regardless of kiln schedule. Because kiln schedule did not significantly affect quality, the use of accelerated drying schedules for drying interior frame parts apparently is feasible. Regardless of the kiln schedule used, successful commercial drying of long or wide cuttings, or of both, from lumber cut from small, low-grade bolts will require special measures to control warp. This may also be true for similar cuttings from standard No. 2 Common lumber.

Low-grade wood residue from logging and sawmilling operations could be used in the manufacture of hardboard for pallet construction, if shown to be satisfactory for this purpose. Generally, this evaluation compared the performance of notched stinger, partial 4-way entry oak pallets having 1-inch-thick medium-density hardboard decks with that of similar red oak pallets under laboratory and service-type conditions. The hardboard-lumber pallets withstood handling impact better; were more (or less) rigid in handling, depending on support conditions; racked much less because of corner-wise drop testing (but also failed sooner); and performed similarly, overall under indoor and outdoor handling and storage conditions. Preliminary work indicated that standard helically threaded pallet nails can be used satisfactorily for hardboard-lumber joints for both exterior and interior exposure. This information should be pertinent to pallet manufacturers and users of pallets, especially to those employing mechanized handling systems. (Author)

Wood fiber for dry-formed hardboard was refined under pressure from red oak and balsam fir. The fiber of each species was adjusted to four acidity levels before treating with two phenolic resins, an alkaline curing and an acid curing, that differed in degree of polymerization. An optimum fiber acidity at which most strength properties reached their maximum was found for each of the two resins. By adjusting fiber acidity, red oak boards had strength properties comparable to balsam fir boards. Boards from various blends of the red oak and the balsam fir fiber adjusted to a common pH value possessed strengths of comparable values. Linear and thickness stability were more dependent on species than were other properties. Acidity control was found beneficial in maintaining board quality. (Author)

Thickness losses encountered in kiln drying and dressing 4/4 red oak lumber were studied. Results suggest that rough dry lumber can be reduced to slightly less than 1 inch thick to produce moderately long, wide cuttings dressed two sides to a thickness of 13/16 inch. Rough dry thickness for panels should be slightly over 1 inch to dress to 13/16 inch. Green 4/4 lumber should be 1/8 inch thicker than required rough dry size to allow for shrinkage. Control of sawing variation and warp during drying are two major problems in trying to reduce green and rough thicknesses of hardwood lumber.

The report discusses the behavior of nailed and stapled reusable oak pallets when impacted by a forklift truck, with and without an impact panel, at approximately two miles per hour. The 48- by 40-inch, partial four-way-entry pallets, fabricated by the U.S. Forest Products Laboratory from locally grown green red oak lumber, were loaded with either 750 or 3,000 pounds.

The dielectric constant and loss tangent of white oak, Douglas-fir, and four commercial hardboards were measured at frequencies from 20 Hertz(Hz) to 50 Megahertz(MHz), moisture conditions from ovendry to complete saturation, temperatures from -20 to +90C., and, for the natural wood, with the electric field alined with three principal structural orientations. The hardboard was measured with the electric field perpendicular to the faces of the board. The behavior of all materials studied was qualitatively similar. The dielectric constant increased with increasing moisture content or temperature, and decreased with increasing frequency.

In-use tests in a combination brick and cement block yard and subsequent laboratory tests indicated that laminated pallet deckboards made from knife-cut, low-grade red oak logs can perform as well as deckboards of solid red oak. Performance was not significantly different between laminated oak deckboard pallets assembled with 2-1/2-in.-long by 15-gage staples and pallets assembled with conventional helically threaded pallet nails if approximately five staples were used for every three nails based on total fasteners per pallet. In a severe handling environment, a synthetic elastomeric adhesive for assembling pallets did not perform as well as nails or staples.

The purpose of the test is to determine the relative performance of the test material to that of asbestos-cement board and red oak flooring under similar test conditions. Results are given for flamespread, fuel contributed, and smoke developed. The values obtained from burning the test material represents a comparison with that of asbestos-cement board expressed as zero and red oak flooring expressed as 100., Report on Surface Burning Characteristics determined by ASTM E-84 Twenty-Five Foot Tunnel Furnace Test Method.

In bonding oak-cottonwood exterior plywood with a low-solids phenolic adhesive, a study was made to determine how much can cure time be reduced and still produce acceptable bonds. Satisfactory results were achieved with a cure time of four minutes. Hot stacking might reduce the time in the press even more. (Author)

The purpose of the test is to determine the relative performance of the test material to that of asbestos-cement board and red oak flooring under similar test conditions. Results are given for flamespread, fuel contributed, and smoke developed. The values obtained from burning the test material represents a comparison with that of asbestos-cement board expressed as zero and red oak flooring expressed as 100., Report on Surface Burning Characteristics determined by ASTM E-84 Twenty-Five Foot Tunnel Furnace Test Method.

The purpose of this investigation is to compare the air drying time of presurfaced oak lumber with that of rough oak lumber. (Author)

Northern red oak was dried under experimental conditions according to various combinations of drying procedures. Reduced drying times with minimal degrade encourage further research on commercial levels. (Author)

The study represents the initial step in applying a number of previous scientific findings to bring about a major improvement in the kiln drying of oak. Therefore, the paper reviews some of the most pertinent background in detail and fully describes the study itself. General recommendations for full application of the results cannot be given until other aspects of the research are completed. Suggestions are given, however, for those who are presurfacing northern red oak. (Author)

The report appraises strength characteristics of round and sawed posts of hickory, oak, and pine for guard posts, sign posts, and other accessory items for highway use. Also provides applicable data on treating characteristics of these species for these purposes. (Author), Prepared in cooperation Wisconsin Univ., Madison.

Northern red oak (Quercus rubra L.) lumber from trees with heartwood infected by certain anaerobic bacteria proved more susceptible to honeyconb and ring failure during kiln drying than similar lumber from non-infected heartwood. Before drying, infected heartwood that was sound and clear of stains appeared the same as non-infected heartwood. However, the infected wood could be distinguished from non-infected green wood by having abnormal sour vinegar and rancid odors which result from volatile fatty acid production by the anaerobic bacteria. (Author)

Bakalárska práca sa zaoberá návrhom a opisom jednotlivých procesov výroby konferenčného stolíka. Obsahuje zhrnutie dnešných trendov výroby stolíkov, návrh vlastného originálneho dizajnu a vhodných konštrukčných spojov. Ďalej je práca zameraná na výber vhodných výrobných technológií, použitých strojov a nástrojov pre výrobu navrhnutého výrobku. Súčasťou práce je potrebná výkresová dokumentácia, výrobný postup zvolenej súčiastky a fotografie zo samotnej výroby., The bachelor's thesis deals with the design and description of individual production processes of a coffee table. It contains a summary of today's trends in the production of tables, and making its own original design and suitable structural joints. Furthermore, the work focuses on the selection of suitable production technologies, used machines and tools for the production of the proposed product. Part of the work is necessary drawing documentation, production process of the selected part and photographs from the production itself.

Bakalárska práca sa zaoberá návrhom a opisom jednotlivých procesov výroby konferenčného stolíka. Obsahuje zhrnutie dnešných trendov výroby stolíkov, návrh vlastného originálneho dizajnu a vhodných konštrukčných spojov. Ďalej je práca zameraná na výber vhodných výrobných technológií, použitých strojov a nástrojov pre výrobu navrhnutého výrobku. Súčasťou práce je potrebná výkresová dokumentácia, výrobný postup zvolenej súčiastky a fotografie zo samotnej výroby., The bachelor's thesis deals with the design and description of individual production processes of a coffee table. It contains a summary of today's trends in the production of tables, and making its own original design and suitable structural joints. Furthermore, the work focuses on the selection of suitable production technologies, used machines and tools for the production of the proposed product. Part of the work is necessary drawing documentation, production process of the selected part and photographs from the production itself.

Bakalárska práca sa zaoberá návrhom a opisom jednotlivých procesov výroby konferenčného stolíka. Obsahuje zhrnutie dnešných trendov výroby stolíkov, návrh vlastného originálneho dizajnu a vhodných konštrukčných spojov. Ďalej je práca zameraná na výber vhodných výrobných technológií, použitých strojov a nástrojov pre výrobu navrhnutého výrobku. Súčasťou práce je potrebná výkresová dokumentácia, výrobný postup zvolenej súčiastky a fotografie zo samotnej výroby., The bachelor's thesis deals with the design and description of individual production processes of a coffee table. It contains a summary of today's trends in the production of tables, and making its own original design and suitable structural joints. Furthermore, the work focuses on the selection of suitable production technologies, used machines and tools for the production of the proposed product. Part of the work is necessary drawing documentation, production process of the selected part and photographs from the production itself.

Bakalárska práca sa zaoberá návrhom a opisom jednotlivých procesov výroby konferenčného stolíka. Obsahuje zhrnutie dnešných trendov výroby stolíkov, návrh vlastného originálneho dizajnu a vhodných konštrukčných spojov. Ďalej je práca zameraná na výber vhodných výrobných technológií, použitých strojov a nástrojov pre výrobu navrhnutého výrobku. Súčasťou práce je potrebná výkresová dokumentácia, výrobný postup zvolenej súčiastky a fotografie zo samotnej výroby., The bachelor's thesis deals with the design and description of individual production processes of a coffee table. It contains a summary of today's trends in the production of tables, and making its own original design and suitable structural joints. Furthermore, the work focuses on the selection of suitable production technologies, used machines and tools for the production of the proposed product. Part of the work is necessary drawing documentation, production process of the selected part and photographs from the production itself.

Předmětem bakalářské práce je zhotovení projektové dokumentace pro stavební povolení a části dokumentace pro provádění stavby na základě zadání, které bylo poskytnuto v předmětu AG032 – Ateliér architektonické tvorby IV. v zimním semestru třetího ročníku na téma veřejné stavby. Studie se zabývá návrhem novostavby komerčního centra do plánovaného resortu v Chorvatsku. Jedná se o třípodlažní budovu, která je částečně zapuštěná do terénu. Svým tvarem i umístěním co nejvíce respektuje stavební parcelu a její okolí. Objekt je složen ze tří funkčních celků. Hlavním z nich je komerční centrum, ve kterém se nachází několik prodejen, restaurací, bar, bistro a mnoho dalších provozů. Budova elipsy, která bude primárně využívána pro odpočinek a relaxaci. Posledním celkem je budova administrativy, ta slouží pouze pro zaměstnance resortu. Všechny tyto části jsou propojeny hlavní komunikací komerčního centra, kterou je výrazný dřevěný ochoz, ten je umístěn na jižní část budovy a nabízí ze všech provozů i samotného ochozu krásný výhled na moře., The subject of the bachelor thesis is the preparation of project documentation for building permits and part of the documentation for the implementation of construction based on the assignment, which was provided in the course AG032 - Architectural Design Studio IV in the winter semester of the third year on the topic of public buildings. The study focuses on the design of a new commercial centre to a planned resort in Croatia. It is a three-storey building that is partially embedded in the ground. Its shape and location respects the building plot and its surroundings as much as possible. The building is composed of three functional units. The main one is a commercial centre with several shops, restaurants, a bar, a bistro and many other facilities. The ellipse building which will be primarily used for rest and relaxation. The last unit is the administration building, this is used only for the resort staff. All these parts are connected by the main corridor of the commercial centre, which is a distinctive wooden walkway, it is located on the southern part of the building and offers a beautiful view of the sea from all the establishments and the walkway itself.