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The provenance variation in natural durability of Douglas fir (Pseudotsuga menziesii (Mirb.) Franco)Akhter, Shaheen January 2001 (has links)
No description available.
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Production of acetic acid in kraft pulp mill biorefinery using bi-polar membrane electrodialysisPatil, Ravikant Amogisidha 13 December 2016 (has links)
<p> The objective of this dissertation was to develop a process for the production of acetic acid in kraft mills. Acetyl groups in hardwood can be hydrolyzed using alkali at 50 °C. The product from this process contains about 15 g/L of sodium acetate and was determined to be suitable for the production of acetic acid.</p><p> Experiments performed using aqueous sodium acetate to evaluate the ability of electrodialysis (ED) to separate and concentrate sodium acetate showed that sodium acetate can be concentrated up to 275 g/L starting with an initial concentration of 17 g/L. The transport of water with sodium and acetate ions through ED membranes limited the maximum obtainable concentration.</p><p> To avoid the deleterious effects of white liquor on ED, selectivity experiments were performed using synthetic oxidized white liquor extract. These experiments showed a decrease in the efficiency of ED process due to the presence of sodium carbonate and sodium sulphate in the extract. Hence, it was concluded that caustic should be used as the extraction solvent.</p><p> Bi-polar electrodialysis (BPMED) experiments performed using sodium acetate showed that up to 200-280 g/L of acetic acid can be produced using BPMED. Although higher concentrations of sodium hydroxide can also be produced using BPMED, 30 g/L concentration was considered to be sufficient for recycle to the extraction process.</p><p> Feed and bleed mode BPMED experiments were performed to determine the current efficiencies and the suitable inlet concentration of sodium acetate for the production of up to 200 g/L of acetic acid. Both feed and bleed mode and batch experiments showed that the current density was the major driving force for BPMED.</p><p> Two types of concentrated wood extracts; namely (1) clarified and (2) unclarified were prepared with and without the lignin removal pre-treatment, respectively. The results of the ED and BPMED experiments performed using these extracts were similar to those of the synthetic sodium acetate. A major difference involved an increase of about 15% in electric energy consumption arising from the transport of formate, lactate and glycolate salts. The color of the anionic membranes slightly changed after processing unclarified extract through ED and BPMED.</p>
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Chemically modified wood for thermally formed compositesTimar, Maria Cristina January 1998 (has links)
No description available.
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A study of home range in two Neotoma fuscipes colonies in Klamath County, OregonFrazier, Brent D. 18 February 1977 (has links)
Home ranges of dusky-footed wood rats (Neotoma fuscipes) were determined by the exclusive boundary strip method in two colonies 630 m apart in Klamath County, Oregon. The mean home range area was 1800 - 1900 m2 . Densities or trees and shrubs were determined on selected home ranges and densities of wood rat houses and nests were determined on all home ranges. No significant correlation was found between home range areas and densities of various trees and shrubs, home range areas and densities of woodrat houses and nests, or home range areas and weights of woodrats in those areas.
No movement between colonies was observed.
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A catalyzed chemimechanical-anthraquinone pulping /Wang, Biao, 1963- January 1997 (has links)
No description available.
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Fighting for the Forests: A History of The Western Australian Forest Protest Movement 1895-2001ronaldchapman1@bigpond.com, Ron Chapman January 2008 (has links)
As the first comprehensive study of Western Australian forest protest the thesis analyses the protest movement's organisation, campaigns and strategies. Its central argument is that the contemporary Western Australian forest protest movement established a network of urban and south-west activist groups which encouraged broad public support, and that a diversity of protest strategies focused public attention on forest issues and pressured the state government to change its forest policies. The forest protest movement was characterised by its ability to continually adapt its organisation and strategies to changing social and political conditions. This flexible approach to protest not only led to victories in the Shannon River Basin, Lane-Poole Reserve and old growth forest campaigns, but also transformed forest protest into an influential social movement which contributed to the downfall of the Court Liberal Government in 2001.
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Pulping qualities of refractory vs. permeable douglas-fir heartwood /Blackman, Gary Lee. January 1970 (has links)
Thesis (M.S.)--Oregon State University, 1970. / Typescript. Mounted photographs. Includes bibliographical references (leaves 64-69). Also available on the World Wide Web.
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Waste from glued wood - A base for new products and/or bio-fuel?Bjurman, Therese January 2009 (has links)
<p> </p><p>The Swedwood Company is a supplier to IKEA of wood furniture. They have grown larger concurrently with IKEA and at present they have 47 production units spread over twelve countries of which most are located in Eastern Europe.</p><p>One of the factories is Zbaszynek which is located in Poland. They manufacture so called board-on-frame furniture. A board-on-frame is basically made out of particle board frames which are filled with special design paper that enfolds air. The frames are then covered with their skin; thinner particle boards, so called High Density Fibre (HDF) boards, and then edge banded with plastic stripes and painted and lacquered into desired design.</p><p>This production generates not only furniture, last financial year Zbaszynek generated about 61 000 tons wood waste too. It can be compared to their total production of furniture which reached 439 000 tons during the same period of time. This generation of wood waste has caused a problem for Swedwood in general. A project called IKEA Goes Renewable (IGR) has started within IKEA with the aim to reduce the electric- and heat energy consumption and increase the use of renewable energy sources. But to be able to reduce the heat energy at a board-on-frame factory, such as Zbaszynek, there has to be an economic incentive to do so. But the wood waste is contaminated in comparison with waste from pure wood (free from adhesives, plastics etc.) so purchasers have been hard to find. And since the wood waste is used to generate the heat at the factories, the economic value has become relative low. Zbaszynek earn 1.4 €/MWh for their wood waste at present (energy value of 5.1 MWh/ton), while for example recycled contaminated wood chippings (RT-chippings) are worth about 7.3 €/MWh in Sweden (energy value of 4.4-5.1 MWh/ton). RT-chippings in Sweden are even allowed to contain more contaminations to receive that price, as long as it is not pressure creosoted. 1.4 €/MWh can also be compared to the economic value of coal which is about 13.7 €/MWh, and for district heating to households in Sweden was the average price about 68 €/MWh during 2007 (Energimarknadsinspektionen, 2007).Therefore, the main task of this thesis has been to investigate if there are any possible solutions to increase the economic value of the wood waste in Zbaszynek. There are more board-on-frame factories within Swedwood with the same problem, but Zbaszynek has been the pilot factory during this research.</p><p>The first thing which should be considered in Zbaszynek is to keep the amount of waste as low as possible. The main task should be to reduce the amounts of wood waste; in the end it is a furniture factory and not a waste producer, which should be concerned before taking any further action. It is assumed though that this has already been thought through in Zbaszynek and further investigation of the waste has taken place.The wood waste has been sent to the Eurofins laboratory in Sweden for an analysis and the test results were then compared to wood waste of pure wood. The comparison indicates the nitrogen content being the main difference between Zbaszynek's wood waste and pure wood. Nitrogen compounds, often referred to as NO<sub>x</sub> can cause severe damage to the environment and foremost lead to increased eutrophication (= Eutrofizacja (Polish) / Övergödning (Swedish)) when it is emitted to the air. Apart from the nitrogen contamination, other significant differences have not been found. The energy content of the wood waste has even revealed it would suit well as bio-fuel, on the condition that proper equipment to reduce the NO<sub>x</sub> emissions is present. It has been calculated that the energy content, of the generated wood waste in Zbaszynek during Financial Year 2008, reached 310 GWh. Which can be compared to the electricity consumption of 78 GWh as was bought during the same time of period.</p><p>Four main possibilities have been investigated in this report and they are:</p><ul><li><p>- Selling the waste to cement producers as alternative fuel</p></li><li><p>- Make new products and use for furniture production again</p></li><li><p>- Make briquettes or pellets and sell as fuel</p></li><li><p>- Start up a Combined Heat and Power plant and produce electricity</p></li></ul><p>All these alternatives have their advantages and disadvantages but they all seem to be realistic solutions, on a few conditions.</p>
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Carbohydrates in a thermomechanical pulp, a sulfite pulp, and a solvent sulfite pulp from western hemlock /Ni, Hae-Rong. January 1983 (has links)
Thesis (Ph. D.)--Oregon State University, 1984. / Typescript (photocopy). Includes bibliographical references (leaves 108-115). Also available on the World Wide Web.
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Two-stage high-yield sulfite pulping of red alder (Alnus rubra Bong.) /Hansen, Edward Dee. January 1967 (has links)
Thesis (M.S.)--Oregon State University, 1967. / Typescript (photocopy). Includes bibliographical references (p. 52-60). Also available on the World Wide Web.
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