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Published: 4 June 2021
Last updated: 31 July 2024

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1

Suttie, Edward Dominic. "The light stabilisation of wood and wood coatings." Thesis, University of Sussex, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427032.

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2

Braun, Moritz. "Simply Wood : Design of All-Wood Furniture Joints." Thesis, Linnéuniversitetet, Institutionen för skog och träteknik (SOT), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-100435.

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The need for sustainability, increasingly requires developing products according to a cradle to cradle approach. For furniture, wood, being potentially renewable, is a suitable material in this regard. However, most wooden furniture today utilizes steels and synthetic polymers in the joints, which can partially be recycled, but are far from being circular materials. All-wood joints have been used in traditional furniture and construction, but they are not adapted to modern manufacturing techniques and do not fulfill the need for easy assembly.  The aim of this thesis is to explore existing solutions for all-wood joints, as well as relevant manufacturing techniques to create an approach for the development of new joints by practitioners. The research questions are: What are the principles used in existing technical solutions and how can they be used to develop new all-wood furniture joints? What are the most important manufacturing techniques for wood today and how can they be considered in the early-stage development? The general approach in this thesis is to abstract the researched existing technical solutions and manufacturing techniques, ideate on this abstract level, and then detail the concepts on a more concrete level.  As results, fourteen different principles and six different patterns of transformation were extracted from existing solutions and documented in an accessible form. Similarly, seven manufacturing techniques were collected and documented. These were then used in an ideation workshop with practitioners from IKEA, which resulted in six abstract concepts. One of the concepts was further developed into a pre-design and tested with a simulations according to strength and stability requirements from applicable standards.  The testing of the pre-design proved its practicality and a team at IKEA is continuing the development of the concept and planning to manufacture a prototype. This is a good indicator for the usefulness of the approach. Even though it worked well, further exploration of the "toolbox" is recommended, as well as the use of different ideation methods. The full environmental benefits of furniture with all-wood joints are not clear, because only resource depletion was considered and the potential effect is small compared to other industries. Despite this, the thesis shows the potential in circular furniture and encourages IKEA and other furniture companies to delve into the topic of circular furniture more deeply.
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3

Barulich, Nadia Stosija. "Magic Wood." Scholarship @ Claremont, 2015. http://scholarship.claremont.edu/cmc_theses/1088.

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This project is a translation of Liu Qingbang's novella 'Shénmù' from Chinese into English. It is also accompanied by an analysis of the text and Li Yang's movie 'Blind Shaft', which was based on the novella.
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4

Carlsson, Peter. "Optimized wood manufacturing with main focus on wood drying." Doctoral thesis, KTH, Building Sciences and Engineering, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-2940.

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Optimization is performed on two applications from woodmanufacturing, with the main focus on wood drying. As anintroductory study of optimization, the design of a modernracing ski is investigated. The skating ski, which is partlybuilt up by wood, is optimized against maximum stiffness withthe restriction of a limited upper weight.

Wood drying is treated as an optimization problem. The totaldrying time is minimized, at the same time as restrictions onmoisture content, stresses and deformations are considered. Theoutcome of the optimization is drying schedules which describethe environmental air dry temperature and relative humidity asa function of time. Design variables during optimization arethe length of the individual time steps and the air drytemperature and relative humidity connected to each time step.Convex approximation methods are used for optimization (the socalled MMA-method, Method of Moving Asymptotes). Necessarygradients are calculated with finite differences.

Optimization is performed with one- and two-dimensional (1Drespectively 2D) moisture transport models. In optimizationwith 1D analysis, moisture content and stresses are calculatedalong a line in the middle of the board, and with 2D analysisthe calculations are made in a numerical grid which covers thecross section of the board. In both cases, deformations arecalculated as the global cup deformation. All structuralcalculations are made with a FEM-program (FEM = Finite ElementMethod) where the whole cross section is modelled with onesingle element. The moisture calculations are made with aFEM-program in the 1D-case, and with a FD-program (FD = FiniteDifference) in the 2D-case. The transient solutions of thestructural and moisture problems are obtained with a timestepping procedure. It is assumed that the moisture problem canbe solved separately from the structural problem, i.e. that thestress and strain distribution during drying has no influenceon the moisture transport.

The wood material is modelled as an orthotropic materialwith main directions in the radial, tangential, andlongitudinal directions. Most material parameters vary with themain direction, the temperature and the moisture content. Thetotal strain rate in the structural calculation is assumed tobe the sum of the elastic strain rate, the moisture inducedstrain rate and the mechano-sorptive strain rate. It ispossible to vary the dimensions of the board and the growthring orientation (i.e. the pith position). In thetwo-dimensional model, it is also possible to simulatedifferent distributions of sapwood and heartwood in the crosssection.

Numerical examples are performed with both 1D and 2Danalysis. In the last example with 2D analysis, optimization isperformed as distributed computing with computers in anetwork.

The thesis shows that optimization methods work well forwood drying. Modern optimization routines offer powerful toolswhen constructing reliable drying schedules. The knowledgeobtained in this work can be used to refine existing dryingschedules, to develop schedules for new quality demands or tocreate schedules for drying kilns with improvedperformance.

Keywords:Optimization, wood drying, distributedcomputing, drying schedules, one-dimensional, two-dimensional,stresses, deformations, moisture content.

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5

YEH, TING-FENG. "Chemical and structural characterizations of juvenile wood, mature wood, and compression wood of loblolly pine (Pinus taeda)." NCSU, 2005. http://www.lib.ncsu.edu/theses/available/etd-11022005-202923/.

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In an effort to comprehensively study the wood property variation in juvenile wood, compression wood, and mature wood, and also to provide a rapid and cost-effective assessment tool to screening the wood chemical property variation, several loblolly pines (Pinus tadea), and transmittance near infrared spectroscopy were utilized in this study. The method development results show that a successful screening of wood chemical property variation, such as lignin and á-cellulose contents, could be adapted using stacked wood wafers microtomed from increment cores and combining with transmittance near infrared spectroscopy. The morphological, chemical, and metabolic analyses of juvenile wood and compression wood show that although compression wood and juvenile wood share some properties, they are actually distinct in their chemistry during development and in final wood chemistry and anatomy. The within tree variation analyses also show that juvenile wood from the top of the tree and that from the base of the tree are more different in morphological structures than in chemical structures. A similar pattern was found between juvenile wood and mature wood. The results obtained suggest that the within tree compression wood percentage and the fiber quality differences inherent in juvenile wood appear to have a greater influence on the final wood products.
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6

Duchow, Kirk J. "Dielectric characterization of wood and wood infiltrated with ceramic precursors." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/19960.

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7

King, Bryan L. "Wood deck bridges-stress laminated wood panels on steel beams." Morgantown, W. Va. : [West Virginia University Libraries], 2001. http://etd.wvu.edu/templates/showETD.cfm?recnum=1860.

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Thesis (M.S.)--West Virginia University, 2001.
Title from document title page. Document formatted into pages; contains xi, 157 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 96).
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8

Nishimoto, Atsushi. "Ecology of sunken wood community in the ocean." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188518.

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9

Birkhimer, Bradley Charles. "Wood ash glaze." Morgantown, W. Va. : [West Virginia University Libraries], 2006. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4573.

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Thesis (M.F.A.)--West Virginia University, 2006.
Title from document title page. Document formatted into pages; contains iv, 27 p. : col. ill. Vita. Includes abstract. Includes bibliographical references (p. 25).
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10

Larsen, Ingrid Marie Hjellset. "Norwegian Wood Innovation." Thesis, Norwegian University of Science and Technology, Department of Computer and Information Science, 2005. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-10219.

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Terrengmodellering i 3D er i dag en mye brukt måte å fremstille landskap på. Slike modeller kan man se i utallige dataspill, animasjonsfilmer, og geologiske modeller. Den vanligste måten å fremstille et 3D terreng på er ved bruk av kotekart. Mønsteret i en treplate kan minne mye om slike koter, og ved segmentering av mønsteret kan dette resultatet behandles på samme måte som et ordinært kart. Denne rapporten beskriver hvordan en finerplate kan bli ført fra treplate til trelandskap ved hjelp av generelle metoder innenfor området for bildebehandlig og 3D modellering. For sluttproduktet blir to løsninger fremstilt. Den ene er et selvlaget program kalt 3Dtre som viser modellen ved hjelp av Delauney triangulering, den andre er basert på bilblioteket SIM scenery og programvare fra Systems in Motion.

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11

Stokes, Agnes. "Wire water wood /." Online version of thesis, 1987. http://hdl.handle.net/1850/11466.

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12

Vice, President Research Office of the. "Wood Wide Web." Office of the Vice President Research, The University of British Columbia, 2006. http://hdl.handle.net/2429/2701.

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13

Öhman, Micael. "The measurement of compression wood and other wood features and the prediction of their impact on wood products /." Luleå, 2001. http://epubl.luth.se/1402-1544/2001/42/index.html.

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14

Scheepers, Gerhardus C. "Liquid water flow and discolouration of wood during kiln drying /." Link to the online version, 2006. http://hdl.handle.net/10019/1189.

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15

Hildén, Lars. "The characterization of wood and wood fibre ultrastructure using specific enzymes /." Uppsala : Dept. of Wood Science, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/s328.pdf.

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16

Shope, Mitchell G. (Mitchell Grafton). "Strength characterization of wood to wood connections using stress field analysis." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/104245.

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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2016.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 69-70).
Minimizing construction cost and material usage are two dominant aspects in structural design. As a building material, timber presents a cheap, renewable option. However, current practice favors steel connections for wood structures. Wood to wood connections offer a solution to the minimization of steel connections. While some wood-only connections are referenced in timber codes, small modifications to these designs as well as a multitude of other possible connection types are yet to be characterized. This thesis analyzes wood to wood joints with stress fields. Stress field analyses may quickly and easily enable the design of timber joints and characterize the maximum loads they can handle. First, this thesis surveys and interconnects the theoretical concepts of wood behavior, plastic design, stress fields, and graphic statics. Additionally, this thesis tests these relationships empirically by load testing a designed double-birdsmouth connection and observing inconsistencies between the theoretical stress field model, code-required strength, and physical tests. The thesis shows that stress fields are a suitable design approach when considering the design of this wood-wood joint. The results also show that careful consideration must be attributed to the material properties of the wood as well as the possible failure modes. This thesis finally shows that shear failure should be checked in addition to compressive and tensile failure and provides a quick method to ensure a safe design.
by Mitchell G. Shope.
M. Eng.
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17

Ren, Dakai. "Moisture-Cure Polyurethane Wood Adhesives: Wood/Adhesive Interactions and Weather Durability." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/29866.

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This project addresses two main subjects of moisture-cure polyurethane (PUR) wood adhesives: wood/PUR interactions and structure-property behavior emphasizing on weather durability. For these purposes, one simplified model PUR (MPUR) and three more commercially significant PURs (CPURs) with different hard segment contents were prepared. Separately, an early side project involved the synthesis of a 13C and 15N double-labeled polymeric methylenebis(phenylisocyanate) (pMDI) resin; this was used for the solid-state NMR characterization of isocyanate cure chemistry in wood bondline. MPUR and a CPUR were employed to investigate whether wood/adhesive interactions influence PUR properties. Wood interactions significantly altered PUR hard/soft domain size distribution (atomic force microscopy, AFM), thermal transition temperatures (dynamic mechanical analyses, DMA), and urethane/urea hydrogen bonds (Fourier transform infrared spectroscopy, FTIR). The effects of hard segment content on properties of PUR prepolymers, and cured PURs (films and wood composites) were studied. Hard segment content largely influenced the PURs’ molecular weights, viscosity, penetration, thermal transitions, and hard segment hydrogen bonds, but only slightly altered the dry (unweathered) bondline toughness. Three accelerated weathering procedures were developed to evaluate CPUR bondline weather durability through mode-I fracture testing. Both hard segment content and weathering conditions were found to significantly influence the bondline weather durability. Among these weathering procedures, only one (VPSS) was able to effectively distinguish weather durability of PUR adhesives, and therefore it was selected for detailed structure-weather durability studies. PUR weather durability was found to correlate with its moisture sensitivity and hard segment softening temperature; both were provided by water-submersion DMA. Much attention was directed to the investigation of weather-induced PUR molecular changes. FTIR studies provided evidences of post-cure, hydrolytic degradation, and variation of urethane/urea hydrogen bonds. DMA presented weathering effects on PUR thermal properties. Special efforts have been made to correlate these analytical results with PUR weather durability. A 13C and 15N double-labeled pMDI resin was synthesized and used for solid-state NMR characterization of isocyanate cure chemistry in wood bondline, particularly to detect the evidence of urethane formation. Rotational echo double resonance (REDOR) NMR clearly revealed the formation of urethane linkages, but largely overestimated their content.
Ph. D.
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18

Fang, Demi L. "Timber joinery in modern construction: Mechanical behavior of wood-wood connections." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/127868.

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Thesis: S.M. in Building Technology, Massachusetts Institute of Technology, Department of Architecture, May, 2020
Cataloged from the official PDF of thesis.
Includes bibliographical references (pages [107]-112).
Timber joinery is a method of geometrically interlocking timber elements prevalent in historic cultures around the world, including North America, Europe, and East Asia. The use of joinery as structural connections faded with the development of metallic screws and nails. Two recent developments offer the opportunity to revive this historic timber connection type: 1) the increasing desire to reduce embodied carbon in buildings by replacing more components with timber as a low-carbon structural material, and 2) recent digital fabrication capabilities which enable the precise milling of complex geometries as an alternative to the time- and labor-intensive handiwork required previously. How can joinery connections be designed in modern structural joints? Can we quantify the sustainability advantage of using these all-timber joints in lieu of the modern convention of metallic fasteners? This thesis addresses both questions as applied to the Japanese Nuki joinery type, though the workflows may be applied to any joinery geometry. First, the rotational stiffness of the Nuki joint is characterized and cross-verified using multiple methods. Second, the embodied carbon of a gravity frame using Nuki joints is compared to that of a gravity frame using conventional metallic fasteners. The use of Nuki joints not only eliminates the use of steel and aluminum but also provides rotational stiffnesses that enable smaller beam sections to be used. It is shown that gravity frames designed with Nuki joints could reduce embodied carbon by over 70% compared to gravity frames designed using conventional beam hanger connections. The findings make a case for all-timber joinery connections to be implemented as a sustainable alternative to conventional metallic connections used in modern timber construction.
by Demi L. Fang.
S.M. in Building Technology
S.M.inBuildingTechnology Massachusetts Institute of Technology, Department of Architecture
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19

Castleberry, Nikole Lee. "Food habits of the Allegheny woodrat (Neotoma magister)." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1413.

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Thesis (M.S.)--West Virginia University, 2000.
Title from document title page. Document formatted into pages; contains viii, 99 p. : col. maps Vita. Includes abstract. Includes bibliographical references.
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20

Sweeney, Ian James. "Fossil wood from the Moreno Hill Formation: Unique expressions of wood mineralization and implications for the processes of wood preservation." Connect to online resource, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1446097.

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21

Mårtensson, Annika. "Interaction between moisture and stress in wooden materials." Lund, Sweden : Lund Institute of Technology, Division of Structural Mechanics, 1988. http://catalog.hathitrust.org/api/volumes/oclc/21753821.html.

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22

Chang, Wei-Ping. "Ultrasound-assisted surface-modification of wood particulates for improved wood/plastic composites." Morgantown, W. Va. : [West Virginia University Libraries], 2008. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5824.

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Thesis (M.S.)--West Virginia University, 2008.
Title from document title page. Document formatted into pages; contains iv, 87 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 83-86).
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23

Shebani, Anour N. "The effect of wood composition and compatibilisers on polyethylene/wood fibre composites." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5270.

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Thesis (PhD (Chemistry and Polymer Science))--University of Stellenbosch, 2010.
ENGLISH ABSTRACT: The effects of the macromolecular composition and content of different wood species on the properties of wood-polymer composites (WPCs) achieved when using poly(vinyl alcohol-co-ethylene) (EVOH) as a compatibiliser and linear low density polyethylene (LLDPE) as a matrix, were investigated. Four wood different species (A. cyclops (acacia), E. grandis (eucalyptus), P. radiata (pine) and Q. alba (oak)) with different macromolecular composition and contents and average particle lengths were used. WPCs filled with these species and WPCs filled with the same species but without extractives were prepared using 10% wood content and different amounts (0, 2, 5, 7 and 10%) of EVOH. An EVOH content of 7% was found to be optimum. Unextracted woods produced WPCs with higher mechanical properties and better resistance to ultraviolet (UV) degradation, while the extracted woods produced WPCs with lower water absorption (WA) rates and better thermal stability. Use of unextracted A. cyclops resulted in composites with superior mechanical and thermal properties compared with the other unextracted species, most probably due to its higher cellulose and lignin contents and a favourable average wood particle length (0.225 mm). A. cyclops composites also had higher WA and thickness swelling (TS) rates most likely due to the greater number of free hydroxyl groups present in these composites because of higher cellulose content. Composites containing wood species with a high lignin and extractive content, such as A. cyclops and Q. alba, exhibited higher resistance to UV degradation. Poly(vinyl alcohol-co-ethylenes) (EVOHs) with different ethylene content (27, 32, 38 and 44%) and A. cyclops with different particle sizes (180, 250 and 450 ìm) were used to prepare WPCs with 10% A. cyclops content. The effect of the contact area between the A. cyclops particles and LLDPE achieved when using EVOHs as compatibilisers on the properties of WPCs was also investigated. The greatest improvements in the mechanical and thermal properties of composites made with A. cyclops with particle size 180 ìm were obtained when EVOH with 44% ethylene content was used. The greatest improvements in the composites made with A. cyclops with particle size 250 ìm were achieved when EVOH with 38% ethylene content was used. Composites made with A. cyclops with particle size 450 ìm exhibited better properties when EVOH with 27% ethylene content was used. All the composites that had better mechanical and thermal properties, also exhibited better compatibility and interface adhesion. Two successful approaches were used to impart more attractive ecological and economical advantages to WPCs. In the first approach, (0, 2, 5 and 7%) degraded LLDPE was used as a compatibiliser in WPCs at levels of 10, 30 and 50% wood content. The resulting mechanical properties, such as tensile strength and hardness, thermal and morphological properties of the compatibilised composites were slightly higher than those of noncompatibilised composites and virgin LLDPE. Elongation at break and impact properties of the compatibilised composites were lower than in virgin LLDPE, but higher than in noncompatibilised composites. In the second approach, polyethylene (PE) and various functionalised polyethylenes (PEs) were synthesised by copolymerising ethylene and 10-undecen-1-ol using a soluble metallocene/methylaluminoxane catalyst at room temperature. The incorporation of functional groups increased with increasing comonomer content. WPCs with 10 and 30% wood content were prepared. The composites prepared with functionalised PEs had better mechanical, thermal and morphogical properties than the composites prepared with PE. Composites made with functionalised PE with higher hydroxyl groups content exhibited better properties than composites made with functionalised PE with lower hydroxyl groups content. Composites with 10% wood content exhibited better properties and performance than composites with 30% wood content.
AFRIKAANSE OPSOMMING: Die gevolg van die makromolekulere samestelling van verskillende houtspesies op die eienskappe van hout-polimeer saamgestelde materiale (HPS) wanneer poli(viniel alcohol-ko-etileen) (EVOH) as versoeningsmiddel gebruik word saam met linieere lae digtheid poli(etileen) (LLDPE) as matriks is ondersoek. Vier houtspesies (A. cyclops (acacia), E. grandis (eucalyptus), P. radiata (pine) and Q. alba (oak)) met verskillende makromolekulere samestelling and partikelgrootte-verspreiding is gebruik in die studie. HPS materiale is berei met hierdie vesels, beide voor en na ekstraksie van die houtpartikels met onderskeidelik warm water en oplosmiddels (alleen en in kombinasie). In hierdie HPS materiale is 10% hout gebruik en 0, 2, 5, 7 en 10% EVOH. 'n EVOH inhoud van 7% is as optimum bepaal. Houtpartikels voor ekstraksie het HPS materiale met beter meganiese eienskappe en beter weerstand teen UV bestraling, terwyle partikels wat ekstraksie ondergaan het HPS materiale met laer water-absorpsie en beter hitte-stabiliteit to gevolg gehad het. Die gebruik van ongeekstraheerde A. cyclops het samegestelde materiale met die beste meganiese en termiese eienskappe tot gevolg gehad in vergelyking met die ander houtspesies (voor ekstraksie), as gevolg van die hoer sellulose en lignien inhoud van die spesie, sowel as 'n voordelige partikelgrootte-verspreiding. A. Cyclops saamgestelde materiale he took hoer waterabsorpsie (WA) en dikte-swelling (DS) tempos gehad, weens die groter hoeveelheid vrye hidroksielgroepe teenwoording in die materiale, direk in verwantskap met die sellulose-inhoud. Saamgestelde materiale met 'n hoe hoevellheid lignien en ekstraheerbare materiale (A. cyclops and Q. alba) het beter weerstand teen UV-degradasie geopenbaar. Verskillende poli(viniel alkohol-ko-etileen) polimere (EVOHs) met wisselende etileen-inhoud (27, 32, 38 en 44%) en A. Cyclops met verskillende partikel-groottes (180, 250 en 250 µm) is gebruik om HPS materiale met 10% hout te vervaardig. Die gevolg van die kontak-area tussen die houtpartikels en die LLDPE wanneer EVOHs as versoeningsmiddel gebruik is, is ook ondersoek. Die beste verbetering in die meganiese en termiese eienskappe van die saamgestelde materiale met A. cyclops met partikel-grootte 180 µm is gekry met EVOH met 44% etileen-inhoud, terwyl die beste resultate met 250 µm partikels verkry is met 'n EVOH met 38% etileen, en met 27% etileen in die geval van die 450 µm partikels. Twee benaderinge om meer aantreklike ekologiese en ekonomiese eienskappe by die HPS materiale te bewerkstellig was suksesvol. In die eerste geval is gedegradeerde LLDPE as versoeningsmiddel gebruik. Die resulterende meganiese eienskappe van die HPS materiale met LLDPE as versoeningsmiddel was beter as die HPS mateirale daarsonder. Samegestelde materiale met 10, 30 en 50% hout is vervaardig. Die trekverlenging by die breekpunt sowel as die impaksterkte van die HPS materiale was laer as LLDPE alleen, maar beter as die nie-versoende HPS materiale. In die tweede benadering is polietileen (PE) en gefunksionaliseerde PE gesintetiseer deur etileen en 10-undekeen-1-ol te koplimeriseer met ‘n oplosbare metalloseen/metiel alumoksaan katalis. Die hoeveelheid funskionele (OH) groepe is verhoog deur toenemend ekomonommer-inhoud. HPS materiale met 10 en 30% hout is vervaardig. Die saamgestelde materiale met funksionele PE het beter maganiese eienskappe gehad as die met gewone PE. Hoe hoër die hidroksielgroep-inhoud, hoe beter die eienskappe van die HPS materiale, terwyl die materiale met 10% hout beter eienskappe openbaar het as materiale met 30% hout.
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24

Mji, N. (Ntuthuzelo). "Pressurised hot water extraction of wood : three wood species prior to pulping." Thesis, Stellenbosch : Stellenbosch University, 2005. http://hdl.handle.net/10019.1/50423.

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Thesis (MSc)--Stellenbosch University, 2005.
No english abstract available.
AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om die effek van warm water uitloging van houtspaanders by hoë temperature en onder hoë druk voor alkaliese verpulping te ondersoek. Warm water uitloging van houtspaanders onder druk voor alkaliese verpulping was baie belowend, aangesien dit ekstrakstowwe verwyder het wat andersins verteringschemikalieë sou opgebruik het en ook verbertede verpulpingstoestande meegebring het. Gedurende uitloging het die houtstruktuur verander agv die verwydering van die ekstrakstowwe. Dit het veroorsaak dat die houtstruktuur meer toeganglik geword het, en dit het gelei tot 'n verbeterde diffusie van die kookloog. Die versnelde kookloogdiffusie het 'n verbeterde en meer gelykmatige delignifikasie meegebring. Warm water uitloging by verhoogde druk is ondersoek vir drie houtsoorte nl. Eucalyptus grandis, Acacia mearnsii en Pinus patuia. 'n Twee-uur en 'n een-uur uitlogingstyd van die houtspaanders voorafgaande Kraft en soda-AQ verpulping is ondersoek.Vergelyk met 'n een-uur uitloging is daar gevind dat die twee-uur uitloging van die houtspaanders te drasties was, met 'n gevolg van 'n vermindering in pulpopbrengs, vesellengte en pulpsterkte. Die verlaging III pulpsterkte kon toegeskryf word aan polisaggariedafbreking. Die een-uur uitloging het 'n hoër opbrengs opgelewer as beide die kontrole (nie uitgeloogde houspaanders) en die twee-uur uitgeloogde houtspaanders. Die een-uur uitlogingsperiode het besonder goeie verpulpingsresultate vir die ekstrakstofryke Acacia mearnsii houtspaanders getoon, met 'n bykomstige verbetering in pulpsterkte eienskappe.
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Hietala, Maiju. "Extrusion processing of wood raw materials for use in wood-polymer composites." Licentiate thesis, Luleå tekniska universitet, Materialvetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26720.

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The interest in wood-polymer composites and their use in different applications has been growing over the last 10-15 years. Environmental issues and demands on lower material costs are the driving forces behind the increasing use of renewable materials such as wood and other natural fibres as reinforcement in polymer composites. Wood flour consisting of small wood particles is currently used as the main wood raw material in commercial wood-polymer composites. However, the reinforcing potential of wood flour is limited. A better reinforcement could be achieved by using wood fibres with a higher aspect ratio as raw material, but individual fibres are seldom used in composite manufacturing due to processing problems and high cost. Therefore, the objective of the work was to study the possibility to use wood chips as raw material and separate individual fibres with higher aspect ratios from the wood chips during the composite manufacturing process. First, the effect of the extrusion process only on wood raw material was studied without a matrix polymer, and then composites using polypropylene as matrix were made. The main goal was to produce wood particles/fibres with high aspect ratio during the manufacturing of wood polymer composites. The effects of extrusion parameters, different screw configurations, raw materials and raw material pre-treatments were evaluated. The size of the separated wood particles and fibres was measured using optical fibre analysis methods. Microstructure of wood particles as well as the fractured surfaces of prepared composites were examined using electron microscopy. The mechanical properties of the composites were measured using flexural and impact testing. The results showed that wood chips can be used as raw material in a one-step manufacturing process of wood-polymer composites. Also, individual fibres with a higher aspect ratio than wood flour were separated from the wood chips with suitable processing conditions
Godkänd; 2011; 20110302 (ysko); LICENTIATSEMINARIUM Examinator: Professor Kristiina Oksman, Institutionen för teknikvetenskap och matematik, Luleå tekniska universitet Diskutant: Associate Professor Roberts Joffe, Institutionen för teknikvetenskap och matematik, Luleå tekniska universitet Tid: Torsdag den 7 april 2011 kl 13.00 Plats: E246, Luleå tekniska universitet
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26

Shiner, Zachary Philip. "An Investigation of Wood and Wood Packaging Waste in the United States." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/84346.

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Each year a large number of wooden pallets are manufactured, recycled, and disposed of during the transportation of goods throughout the United States. The production of these pallets consumes a significant amount of wood and a large number of pallets also end up in landfills at the end of their useful life cycle. However, these pallets can be recovered through repair, broken apart into components, ground into mulch, fuel, animal bedding, or used by landfills for day to day operations. The purpose of this research was to investigate the total number of pallets and crates reaching landfills in the United States as well as to gain a better understanding of the overall waste stream. This was done by surveying all licensed Municipal Solid Waste (MSW) and Construction and Demolition (CandD) landfills in the continental United States. A questionnaire was sent to these landfills, and this entire study was intended to build upon previous Virginia Tech landfill surveys conducted in 1995 and 1998 with some changes made after careful review. Overall, it was found the average MSW facility in the United States received 185,077 tons of waste and the average CandD facility received 74,911 tons. This results in a total national estimate of 253 million tons of MSW and 76.9 million tons of CandD waste. Approximately 18.3 million pallets were landfilled and an additional 13.8 million were recovered, repurposed, or reused at MSW facilities. At CandD facilities, approximately 19.2 million pallets were landfilled while 38.3 million were recovered.
Master of Science
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27

Sterley, Magdalena. "Green gluing of wood." Licentiate thesis, KTH, Civil and Architectural Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1737.

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28

Wålinder, Magnus. "Wetting phenomena on wood." Doctoral thesis, KTH, Production Systems, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-2908.

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Leverick, Robert Thomas. "Shaping wood/naming shapes /." Online version of thesis, 1990. http://hdl.handle.net/1850/11317.

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30

Oveisi-Fordiie, Ehsanollah. "Durability of wood pellets." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/34002.

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Durability is used for quantifying the quality of pellets by measuring the percentage of broken pellets. This work conducted durability measurement using different approaches, including Dural, Tumbler and drop test, and established relationship between them. In particular, 1) we developed a robust method that measures durability based on Dural. A series of experiments were conducted using eight different machine settings and four types of pellets. It was found that both pellet types and machine settings are statistically significant. The setting represented by 200 g sample, testing duration 15 s and rotational speed 1516 rpm was found to be the most appropriate for Dural. 2) We also conducted drop test for unveiling the effect of different factors on breakage of pellets, such as height, sample size, number of repeated drops, type of bedding and type of pellet. The relation between breakage and height was found to be linear. Harder surface had more impact on pellets. The percentage of dust increased significantly after each drop as the pellets tended to break more readily and the accumulation of fines was approximately 10% after five drops. An asymptote was observed for sample size greater than 1000 g. 3) Finally, we investigated correlations of durability measurement among Tumbler, Dural and drop test. When wood pellets were used, a strong correlation (R² = 0.76) was observed between the Tumbler-measured durability and the Dural-measured durability with a logarithmic curve. The correlation between the durability derived from the drop test versus the Dural tester was significantly stronger (R² = 0.81) than when it was compared to the Tumbler tester (R² = 0.63).
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31

Hansen, Helge Johannes. "Acoustic Studies on Wood." Thesis, University of Canterbury. School of Forestry, 2006. http://hdl.handle.net/10092/1746.

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Several acoustic techniques have been used to determine elastic and damping properties of trees, logs and beams. Time of flight (TOF) measurements in the outerwood of 14-year-old Pinus radiata trees showed that pruning operations increased the outerwood stiffness by up to 25% compared with unpruned trees. However, at the most 5% to 10% of the increased stiffness can be explained by the fact that the outerwood of the pruned trees is free of knots, as TOF measurements are little affected by knots. Thus, it is not known what causes the increase of outerwood stiffness in the pruned trees. One possible explanation could be a smaller microfibril angle (MFA) in the S2 layer of the outerwood cells, which would cause a significant increase in stiffness. Thinning operations decreased the outerwood stiffness by up to 8%. In small Eucalyptus nitens and Pinus radiata logs, which had branch nodes and nodal whorls at specific locations, MOE calculations (using the resonance technique) based on different harmonics gave different results. This indicates that defects do interact with acoustic waves. Acoustic tests on laminated beams with artificial defects (holes filled with dowels) at specific locations also had a significant impact on the MOE. Moreover, it was evident that the damping ratio (evaluated from the Q- factor) of the beams increased with increasing diameter of the holes. However, it was found that holes in laminated beams decreased stiffness while branch nodes and nodal whorls increased stiffness. This shows that relatively small defects, occupying a small volume of the beam, have an impact on acoustic measurements. It is not appropriate to base the MOE calculation on a single harmonic, considering that different harmonics investigate different parts of the specimen
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32

Ryan, Jessica. "CRASHING AGAINST THE WOOD." Master's thesis, University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2788.

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In this collection of short stories, the characters struggle to recover equilibrium in their lives that have been turned upside down. They struggle against one another, against change, and against the loss of loved ones. No matter what bonds hold the characters together, the underlying tension of change and reaction permeates their relationships and threatens what they know to be true. A theme of discontent runs in these stories. Something beneath the surface is not right, and the characters struggle to climb out of the mess their lives have become. Some of them have been stifled, like the narrator in "Resounding Gong, Clanging Cymbal," who’s being pressured on all sides to marry. Some of them are toeing the line of fitting in and being independent, like the teenagers in "Hibiscus Boulevard," who, caught up in the last days of summer, are more concerned with being adults than being kids. In the title story, the teenagers in a small town find a way to memorialize one of their own by performing the act that caused him to die. The cautious bonds between the characters are continuously being worked by one another, by oppressive scenery and location, by the aftereffects of dysfunction, or by unrequited love. No matter what the context or situation, something is always just a little bit off, or wrong, in each story in this collection, and the characters must do their best to correct the situations.
M.F.A.
Department of English
Arts and Humanities
Creative Writing MFA
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33

Chen, Zheng. "Torsional fatigue of wood." Thesis, London South Bank University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271780.

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34

McIlveen-Wright, David. "Electricity generation from wood." Thesis, University of Ulster, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241990.

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35

Sedighi, Moghaddam Maziar. "Wettability of modified wood." Doctoral thesis, KTH, Yt- och korrosionsvetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-175875.

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Despite many excellent properties of wood which make it suitable for many applications, it suffers from a number of disadvantages limiting its use. For instance, modification is needed to reduce water sorption and to improve decay resistance, dimensional stability and weathering performance. In addition, wood/liquid interaction such as water wettability on wood plays an important role in design and characteristics of many processes and phenomena such as adhesion, coating, waterproofing, wood chemical modification, and weathering. This thesis focuses on enhancing the understanding of wetting of wood, with emphasis on modified wood. The influence of surface chemical composition of wood and its microstructural characteristics on wetting and swelling properties has also been studied. A multicycle Wilhelmy plate technique has been developed to evaluate wetting properties of porous materials, such as wood, in which the samples were subjected to repeated immersions and withdrawals in a swelling liquid (water) and in a non-swelling liquid (octane). This method was utilized to dynamically investigate contact angle, sorption and swelling properties, as well as dimensional stability of unmodified, chemically and surface modified wood samples. Scots pine sapwood and heartwood samples were utilized to establish the principles of the technique. Acetylated and furfurylated wood samples with different level of modification were thereafter examined utilizing the developed technique for wetting measurements. A perimeter model based on a linear combination of the measured force and final change in sample perimeter was suggested to evaluate the dynamic dimensional stability of wood veneers. The feasibility of this method for studying dynamic wettability was investigated by measuring the changes of advancing and receding contact angles over repeated cycles on surface modified wood samples, created by combining liquid flame spray and plasma polymerisation methods. X-ray photoelectron spectroscopy (XPS) and X-ray computed tomography (XCT) were employed to study the surface chemical composition and microstructural properties of the samples, respectively. Three different kinetic regimes were observed in the wetting measurements: i) fast wetting and spreading of the liquid on the wood surface, ii) void filling and wicking and iii) swelling, which was the slowest of the three. The multicycle Wilhelmy plate method was found to be suitable for studying liquid penetration, sorption, and dimensional stability of swelling materials. The results demonstrate that the wetting properties of wood are highly affected by surface chemistry and microstructure. It was shown that using both swelling and non-swelling liquids in wetting measurements allow to distinguish between capillary liquid uptake and swelling. Based on this, for chemically modified samples, it was demonstrated that acetylation mostly reduces swelling, while furfurylation reduces both swelling and capillary uptake. This is in line with the microstructural study with X-ray computed tomography where a significant change in the porosity was found as a result of furfurylation, conversely acetylation left the total porosity values unchanged. Wetting results for hydrophobised wood samples demonstrate that the multi-scale roughness obtained by combination of nanoparticle coating and plasma polymerization increased both the hydrophobicity and the forced wetting durability compared to the micro-scale roughness found on wood modified with plasma polymerisation alone.

QC 20151029


Sustainable wood modification
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36

Hansson, Lars. "Microwave treatment of wood." Doctoral thesis, Luleå tekniska universitet, Träteknologi, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26364.

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Drying wood using microwave energy is not very common, but could be a complement to conventional air-circulation drying due to the possibility to dry wood faster than the conventional drying methods with preserved quality. Furthermore, this technique could be used to condition boards with too high moisture content gradient. In this study, an industrial-scale, online microwave drier for wood components has been used and adapted to wood treatment. The aim of the present work was to investigate if the microwave drying method itself affects such wood properties as bending strength, hardness and colour change. Another aim was to explain, with finite element model simulations, the interaction between microwaves and wood during heating and drying and to a lesser extent also during microwave scanning of wood. Tests of the mechanical properties of wood showed no difference in bending strength in comparison with the conventional air circulation method. Nor was there any significant difference in wood hardness (Janka) perpendicular to the grain between the drying methods or between different temperature levels during the microwave drying. However, the results showed that there is a significant difference in wood hardness parallel to the grain between the methods when drying progressed to relatively lower levels of moisture content; i.e. wood hardness becomes higher during microwave drying. The developed multiphysics finite element model is a powerful evaluation tool for understanding the interaction between wood and microwaves during heating and drying as well as scanning. The model can be used for simulation of different microwave treatments of wood.
Godkänd; 2007; 20071015 (ysko)
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37

Vega, Rivera Jorge Humberto. "Premigratory movements of a long-ddistancemmigratory [sic] species, the wood thrush (Hylocichla mustelina)." Connect to this title online, 1997. http://scholar.lib.vt.edu/theses/available/etd-3739142349751421/.

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38

Twomey, Brian M. "The performance and behavior of lightweight wood exposed to fire conditions." Link to electronic thesis, 2007. http://www.wpi.edu/Pubs/ETD/Available/etd-050207-154942/.

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39

Castleberry, Steven Bryan. "Conservation and management of the Allegheny woodrat in the central Appalachians." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1503.

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Thesis (Ph. D.)--West Virginia University, 2000.
Title from document title page. Document formatted into pages; contains xv, 166 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references.
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40

Köpcke, Viviana. "Conversion of Wood and Non-wood Paper-grade Pulps to Dissolving-grade Pulps." Doctoral thesis, KTH, Träkemi och massateknologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-26967.

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Dissolving-grade pulps are commonly used for the production of cellulose derivatives and regenerated cellulose. To obtain products of high quality, these so-called "special" pulps must fulfill certain requirements, such as high cellulose content, low hemicellulose content, a uniform molecular weight distribution and high cellulose reactivity. Most, if not all, of the commercial dissolving pulps accomplish these demands to a certain extent. Nevertheless, achieving high cellulose accessibility as well as solvent and reagent reactivity is not an easy task due to the compact and complex structure presented by the cellulose. In the first part of this work, three commercial monocomponent endoglucanases were investigated with the purpose of enhancing the cellulose accessibility and reactivity of a hardwood dissolving pulp. A monocomponent endoglucanase with a cellulose-binding domain (CBD) was shown to significantly improve the cellulose reactivity. The positive effect of this enzyme on dissolving-grade pulps was also observed on paper-grade pulps. The main focus of the forest industry is the production of paper-grade pulps. Paper-grade pulps are mostly produced by the kraft process. In contrast, dissolving-grade pulps are produced by the sulfite and prehydrolysis kraft processes due to the high purity required for these pulps. The kraft process is known for being the most efficient process in terms of energy and chemical recovery, which makes the production costs of paper-grade pulps lower than those of sulfite dissolving-grade pulps. Besides, the production of dissolving pulps present, among others, higher capital and chemical costs than paper-grade pulps. Therefore, the viability of converting paper-grade pulps into dissolving pulps is brought into a question. However, this task is not simple because paper-grade pulps contain a lower cellulose content and a higher hemicellulose content than dissolving pulps. They also present lower cellulose reactivity and an inhomogeneous molecular weight distribution. As a consequence, the second part of this work focused on the study of the feasibility of converting kraft pulps into dissolving pulps. Several sequences of treatments of hardwoods and non-wood pulps were investigated. The best sequence for each suitable pulp was developed, and the parameters involved were optimized. After several attempts, it was demonstrated that pulps from birch, eucalypt and sisal fulfill the requirements of a commercial dissolving pulp for the viscose process after being subjected to a sequence of treatments that included two commercial enzymes, a xylanase and a monocomponent endoglucanase, and alkali extraction steps.
QC 20101201
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41

Rezaei, Hamid. "Physical and thermal characterization of ground wood chip and ground wood pellet particles." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/60914.

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The goal of the present study is to characterize the ground chip and ground pellet particles with respect to their size, shape, density, flow properties, drying and pyrolysis mass loss. Commercial wood pellets and pulp-quality wood chips are used in this study. These commercial samples are ground in the laboratory using a range of grinder screen sizes. The grinder power input is measured. The ground particles are examined for their size and shape. The ground particles are thermally treated in a micro TGA equipment and in a lab-scale thin-layer drying/pyrolysis equipment. The grinding results show that grinding a whole pellet to the desirable particle sizes for pyrolysis (~1 mm) takes around 1/7 of energy required to grind a whole wood chip to the same mean particle size. Pellet particles are denser, more spherical and shorter than the needle-shape chip particles. The spheroid shape of ground pellet particles lowers the compressibility of bulk, lowers the cohesion among the particles and facilitates their flowability. Higher density and random fiber orientation of the pellet particles prolong the duration of their drying significantly compared to the drying time of thin and long wood chip particles. Further moisture diffusion modeling shows that the moisture diffusion rate inside the pellet particles is half of those inside the chip particles. Although chip and pellet particles show the same level of shrinkage in size of a single particle due to drying, ground pellet particles exhibit a larger reduction in their bed porosity than the bed porosity measured for ground chip particles. Both chip and pellet particles reach their fiber saturation point at a moisture content of around 0.50 (dry basis). The pyrolysis kinetic parameters are determined experimentally and a two-zone kinetic mechanism is modeled and validated using the experimental thin-layer pyrolysis data.
Applied Science, Faculty of
Chemical and Biological Engineering, Department of
Graduate
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42

Gravelsins, Robert J. "Studies of grinding of wood and bark-wood mixtures with the Szego mill." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0003/NQ33903.pdf.

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43

Andersson, Gunnerås Sara. "Wood formation and transcript analysis with focus on tension wood and ethylene biology /." Umeå : Dept. of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/200515.pdf.

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44

Michaelis, L. A. "Evaluation of wood-based energy technologies and the options for wood in Kenya." Thesis, University of Cambridge, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382640.

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45

Kunstmann, Martin. "Comparative LCA of Wood from Conventional Forestry and Wood from Short Rotation Coppice." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-135927.

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Worldwide there is an increasing demand of natural resources. In future, non renewable resources get substituted by renewable resources in the energetic sector as well as in the material sector. That implies a stronger usage of renewable resources especially - wood. In 2009 there was a usage of 77 million cubic meters of wood for material applications and a quantity of 55 million cubic meters for energetic applications in Germany alone. Furthermore, there is an increasing demand on wood for energetic purposes. In 2007 this problematic development led to the first supply bottlenecks. To meet the increasing demands of the future, Short Rotation Coppices (SRC) can help to improve the wood provision. An SRC is a planting of fast growing coppice on agricultural areas, which is managed more intensively than usual forestry practices for a quicker production of wooden biomass. With a comparative LCA of conventional wood and wood from SRC the present study evaluates if wood from SRC is reasonable to cover the increasing demand of wood for material and energetic purposes in an environmental friendly way. A comprehensive literature research regarding LCAs of wood and wooden products shows that there are no previous studies comparing the two types of wood. Hence, the present study examines a particleboard production as the material scenario and the combustion of woodchips in a firing system as the energetic scenario to compare the ecological advantages and disadvantages of wood from SRC and conventional wood. The LCA is implemented with the Gabi software designed by PE International. Data is obtained from previous LCA studies evaluating the production of wood, the particleboard production and the combustion of wood. Additionally, data from the Ecoinvent database is used. Functional units are the production of 1m3 particleboard and the production of 1 MJ of thermal energy. The LCIA is implemented with the “Ecoindicator” as endpoint- and “CML 2001” as midpoint approach to cover broad range of environmental issues. Moreover a sensitivity analyses shows the impact of decisive variables on the results of “Ecoindicator” and “CML 2001”. Results reveal that outcomes of the LCIA are dependent of the assessment method and the processed part of trees from conventional forestry. The present study shows, that with an efficient land use, wood from SRC can help to cover the increasing demand of wood for material and energetic purposes in a sustainable way. However, an immediate usage of wood for energetic purposes has to be seen critical. Instead, a cascaded and sustainable utilization of wood is recommendable to counteract climate change and to improve the efficient use of the renew-able resource - “wood”.
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46

Kunstmann, Martin. "Comparative LCA of Wood from Conventional Forestry and Wood from Short Rotation Coppice." Technische Universität Dresden, 2012. https://tud.qucosa.de/id/qucosa%3A27690.

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Worldwide there is an increasing demand of natural resources. In future, non renewable resources get substituted by renewable resources in the energetic sector as well as in the material sector. That implies a stronger usage of renewable resources especially - wood. In 2009 there was a usage of 77 million cubic meters of wood for material applications and a quantity of 55 million cubic meters for energetic applications in Germany alone. Furthermore, there is an increasing demand on wood for energetic purposes. In 2007 this problematic development led to the first supply bottlenecks. To meet the increasing demands of the future, Short Rotation Coppices (SRC) can help to improve the wood provision. An SRC is a planting of fast growing coppice on agricultural areas, which is managed more intensively than usual forestry practices for a quicker production of wooden biomass. With a comparative LCA of conventional wood and wood from SRC the present study evaluates if wood from SRC is reasonable to cover the increasing demand of wood for material and energetic purposes in an environmental friendly way. A comprehensive literature research regarding LCAs of wood and wooden products shows that there are no previous studies comparing the two types of wood. Hence, the present study examines a particleboard production as the material scenario and the combustion of woodchips in a firing system as the energetic scenario to compare the ecological advantages and disadvantages of wood from SRC and conventional wood. The LCA is implemented with the Gabi software designed by PE International. Data is obtained from previous LCA studies evaluating the production of wood, the particleboard production and the combustion of wood. Additionally, data from the Ecoinvent database is used. Functional units are the production of 1m3 particleboard and the production of 1 MJ of thermal energy. The LCIA is implemented with the “Ecoindicator” as endpoint- and “CML 2001” as midpoint approach to cover broad range of environmental issues. Moreover a sensitivity analyses shows the impact of decisive variables on the results of “Ecoindicator” and “CML 2001”. Results reveal that outcomes of the LCIA are dependent of the assessment method and the processed part of trees from conventional forestry. The present study shows, that with an efficient land use, wood from SRC can help to cover the increasing demand of wood for material and energetic purposes in a sustainable way. However, an immediate usage of wood for energetic purposes has to be seen critical. Instead, a cascaded and sustainable utilization of wood is recommendable to counteract climate change and to improve the efficient use of the renew-able resource - “wood”.
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47

Mathieu, Valentin. "Wood, Cities, and Trade : An Economic Analysis of the Global Urban Demand for Wood Products and the Dynamics of International Wood Trade." Electronic Thesis or Diss., Université de Lorraine, 2023. http://www.theses.fr/2023LORR0267.

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Pour atteindre les objectifs de développement durable et de gestion durable des ressources naturelles, une compréhension approfondie des différents facteurs qui contribuent à l'économie du bois, ainsi qu'une prévision précise de l'offre et de la demande de bois, sont essentielles. De telles analyses s'appuient sur des modèles, appelés dans cette thèse “modèles de flux commerciaux de bois” lorsqu'ils étudient la production, le commerce et la consommation de bois. L'utilisation de modèles pour expliquer et prédire des phénomènes économiques se heurte à plusieurs difficultés méthodologiques. Face à ces difficultés, comment évaluer la capacité d'un modèle à conduire de telles analyses ? Cette thèse considère trois aspects essentiels et interdépendants de la modélisation pour évaluer la capacité d'un modèle à atteindre ses objectifs. Le premier aspect consiste à déterminer si les fondements théoriques des modèles peuvent être testés empiriquement. Le deuxième aspect consiste à déterminer si un modèle prend en compte des facteurs importants pour l'analyse heuristique et prédictive des phénomènes économiques. Le troisième aspect concerne la disponibilité et la qualité des données sur lesquelles une théorie peut être testée et à partir desquelles des facteurs peuvent être identifiés et quantifiés. Cette thèse est structurée autour de ces trois aspects et est divisée en quatre chapitres. Les deux premiers chapitres portent sur deux des aspects de la modélisation considérés : (i) les facteurs pris en compte ou à prendre en compte dans la modélisation de l'économie du bois, et (ii) l'élaboration de modèles fondés sur une théorie empiriquement vérifiable. Les deux derniers chapitres traitent du troisième aspect de la modélisation : la qualité des données et ses implications pour la modélisation. L'objectif de cette thèse est de mener une revue des facteurs considérés pour modéliser les flux commerciaux de bois, et de proposer une analyse économique de la demande urbaine en bois et du commerce international des produits bois. Le chapitre 1 présente une méta-analyse des concepts de modélisation des flux commerciaux du bois. Il conclut que les modèles économiques s'appuient sur un ensemble restreint de quatre catégories de facteurs, négligeant ainsi d'autres facteurs importants, comme l'urbanisation. Le chapitre 2 développe une modélisation spatiale de la demande urbaine en bois. En prenant en compte l'urbanisation comme facteur de l'économie mondiale du bois, le modèle propose une représentation réaliste et précise des phénomènes économiques forestiers, suggérant un rôle déterminant des dynamiques urbaines dans l'économie globale du bois. Le chapitre 3 met en évidence plusieurs incohérences entre les données d'exportation et d'importation et propose une méthode pour tenir compte des erreurs de mesure dans les analyses commerciales. Ce chapitre suggère que ces disparités sont significatives et que le fait de ne pas corriger les modèles pour tenir compte des erreurs dans les données commerciales biaise les résultats des modèles. Le chapitre 4 effectue une analyse de réseau du commerce du bois rond. Bien que cette analyse soit principalement descriptive, elle fournit un modèle réaliste et mécaniste d'évaluation de la structure du réseau commercial et ses dynamiques. Les contributions scientifiques de cette thèse sont triples: elle propose de nouvelles méthodes pour modéliser l'économie mondiale du bois, intègre la dynamique urbaine comme un facteur qui façonne l'économie mondiale du bois, et met en avant un besoin de meilleures pratiques dans l'analyse du commerce des produits bois. Elle s'inscrit dans les enjeux globaux en mettant en avant la nécessité d'anticiper la future demand urbaine en bois, questionne l'efficacité des politiques de régulation économique appliqués aux forêts et aux produits bois, et suggère des stratégies commerciales visant à minimiser les risques de marché
To achieve sustainable development and sustainable natural resource management, a thorough understanding of the various factors that contribute to the wood economy, as well as an accurate forecast of wood supply and demand, are essential. Such analyses rely on models, referred to in this thesis as "wood trade flow models" when studying wood production, trade and consumption. The use of models to explain and predict economic phenomena comes up against several methodological difficulties. Given these difficulties, how can we assess a model's ability to conduct such analyses? This thesis considers three essential and interdependent aspects of modeling to assess a model's ability to achieve its objectives. The first is whether the theoretical framework of models can be tested empirically. The second aspect is to determine whether a model takes into account factors that are important for the heuristic and predictive analysis of economic phenomena. The third aspect concerns the availability and quality of data on which a theory can be tested and from which factors can be identified and quantified. This thesis is structured around these three aspects and is divided into four chapters. The first two chapters deal with two of the modeling aspects considered: (i) the factors taken into account or to be taken into account in modeling the wood economy, and (ii) the development of models based on empirically testable theories. The last two chapters deal with the third aspect of modelling: data quality and its implications for modelling. The aim of this thesis is to conduct a review of the factors considered in modeling wood trade flows, and to propose an economic analysis of urban demand for wood and international trade in wood products. Chapter 1 presents a meta-analysis of wood trade flow modeling concepts. It concludes that economic models rely on a narrow set of factor categories, thus neglecting other important factors, such as urbanization. Chapter 2 develops a spatial model of urban demand for wood. By taking urbanization into account as a factor in the global wood economy, the model offers a realistic and accurate representation of forest economic phenomena, suggesting a crucial role of urban dynamics in shaping the global wood economy. Chapter 3 highlights several discrepancies between export and import data, and proposes a method for accounting for measurement errors in trade analyses. This chapter suggests that these discrepancies are significant, and that failing to correct models for errors in trade data biases model results. Chapter 4 performs a network analysis of the roundwood trade. Although this analysis is primarily descriptive, it provides a realistic and mechanistic model for assessing the structure of the trade network and its dynamics. The scientific contributions of this thesis are threefold: it proposes new methods for modeling the global wood economy, integrates urban dynamics as a factor shaping the global wood economy, and highlights a need for best practices in the analysis of wood product trade. It addresses global issues by highlighting the need to anticipate future urban demand for wood, questions the effectiveness of economic regulation policies applied to forests and wood products, and suggests commercial strategies aimed at minimizing market risks
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48

Slahor, Jeffrey J. "Preservative treatment evaluation of five Appalachian wood species with four preservatives." Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=599.

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Thesis (M.S.)--West Virginia University, 1999.
Title from document title page. Document formatted into pages; contains xiii, 85 p. : ill. Includes abstract. Includes bibliographical references (p. 82-85).
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49

Louro, Graça Maria Cabaço. "Modelo global para as fileiras silvo-lenhosas." Doctoral thesis, ISA/UTL, 2011. http://hdl.handle.net/10400.5/3873.

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Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia
The production flows in the sector of wood construction and furniture, paper and paper board and that of wood, paper and paper board wrapping and packaging sector are analyzed. The macroeconomic indicators associated with them are characterized, showing their importance in the Portuguese national economy. The characteristics of the corresponding enterprises and workforce, as well as the main domestic and international market trends for the different phases of the productive cycle are described. The recent evolution of wood production from maritime pine (Pinus pinaster Aiton) and eucalyptus (Eucalyptus globulus) is described and analyzed in a context that takes in account their potential to supply raw material for wood based industries. The effect of forest fire regimes and cuts on wood availability is modeled, using National Forest Inventories data and wildfire statistics. The models were used in predictions of future wood availability under various fire scenarios. Models for the supply and domestic consumption of sawn wood, wood panels, wood pulp, and paper and paper board, based on econometric equations, were developed.
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50

Stevens, Jason. "Material Properties of Wood Ash-Filled and Wollastonite-Filled Polyproplyene Wood Plastic Composites (WPCS)." Fogler Library, University of Maine, 2011. http://www.library.umaine.edu/theses/pdf/StevensJ2011.pdf.

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