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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Untersuchungen von Holzmerkmalen junger Fichten (Picea abies (L.) Karst.) Jahrringbreite, Rohdichte und Ästigkeit von Stecklingsklonen /

Lewark, Siegfried, January 1900 (has links)
Thesis (doctoral)--Georg-August-Universität zu Göttingen. / Vita. Includes bibliographical references (p. 161-169).
12

Compression wood in Scots pine and Norway spruce : distribution in relation to external geometry and the impact on dimensional stability in sawn wood /

Warensjö, Mats. January 2003 (has links)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2003. / Thesis documentation sheet inserted. Appendix includes reprints of five papers and manuscripts, four co-authored with others. Includes bibliographical references. Also issued electronically via World Wide Web in PDF format; online version lacks appendix.
13

Dead wood retention and the risk of bark beetle attack /

Hedgren, Per Olof, January 2002 (has links)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2002. / Thesis statement in Swedish and English abstract inserted. Appendix reprints four papers and manuscripts, three co-authored with others. Includes bibliographical references. Also issued electronically via World Wide Web in PDF format; online version lacks appendix.
14

Nutrient changes in Norway spruce foliage following diagnostic fertilization

Janicki, Wlodzimierz S. January 1992 (has links)
The nutrient status of three Norway spruce (Picea abies L. Karst.) plantations in southwestern Quebec were studied through foliar analysis. At all locations low N and K and marginal Mg foliar concentrations were identified. / Diagnostic fertilization resulted in significantly improved foliar K, N, Ca/K molar ratio and in some cases Mg. The foliage of the treated trees has an improved dark green colour as compared with the controls. From this research it is evident that nutrient deficiencies of N, and K in particular, are showing up in spruce stands in the areas where atmospheric pollution is relatively severe. The use of foliar nutrient concentrations along with evaluation of visual decline symptoms give the best results in assessment of the trees' current nutrient status. Proper diagnostic fertilization, using KNO$ sb3$ and (K,Mg)SO$ sb4$, helped to correct the nutrient disturbances on the calcareous soils of the region, impoverished by former agricultural use. In these soils the balance of Ca with K and Mg is crucial for their proper uptake. The base cations addition enlarged the available P pool, as a result of the improved organic matter decomposition. (Abstract shortened by UMI.)
15

Nutrient changes in Norway spruce foliage following diagnostic fertilization

Janicki, Wlodzimierz S. January 1992 (has links)
No description available.
16

Nondestructive testing (NDT) of Norway spruce with respect to infection by root and butt rot using ultrasound and acoustic methods.

Sturesson, Claes January 2011 (has links)
No description available.
17

Permeability in surface treated Norway spruce samples- Effect of wood properties / Fuktupptag i ytbehandlade granprover- Virkesegenskapers påverkan

Nilsson, Josefin January 2012 (has links)
In Norway spruce there's a large natural variation in durability but knowledge about what is causing this variation is missing. In this thesis the focus were put into investigating how the water uptake ability was affected by the influence of heartwood versus sapwood and wood properties such as density and annual ring width. Liquid water permeability was checked trough a modified version of EN 927-5 and samples were also investigated trough the Mycologg Method. The wide grown wood with a coating system (a priming oil and alkyd or acrylate paint) absorbed less water than the narrow grown wood in the permeability test. The Mycologg test showed a clear difference between wide and narrow grown wood. Further research is necessary to examine the impact of wood properties when it comes to water uptake.
18

Morphology of Norway spruce tracheids with emphasis on cell wall organisation /

Brändström, Jonas. January 2002 (has links)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2002. / Thesis documentation sheet inserted. Appendix reprints four papers and manuscripts, three co-authored with others. Includes bibliographical references. Issued also electronically via World Wide Web in PDF format; online version lacks appendix.
19

Fibres orientation on sawn surfaces : Can fibre orientation on sawn surfaces be determined by means of high resolution scanning / Fiber riktningen på sågade ytor : Kan fiber riktningen på sågade ytor bestämmas med hjälp av högupplöst scanning

Briggert, Andreas January 2014 (has links)
In 2013 the European journal of wood and wood products published an article regarding a new method to predict strength in structural timber (Olsson et al 2013). By determining the fibres orientation on all four surfaces of each board in sample of timber using a high resolution scanner the authors were able to achieve a coefficient of determination, R2, as high as 0.71 between bending strength and a new indicating property (IP). For the same sample of timber Olsson et al (2013) determined the R2 by axial dynamic excitation as 0.59. However, all boards used in their investigation were planed before scanning. This study examines if a high resolution scanner could be used to determine the fibre orientation on the surfaces of sawn timber boards of Norway spruce. Both band sawn surfaces and circular sawn surfaces were examined. The procedure in this investigation is described as follows. Firstly, both the band sawn and the circular sawn boards were scanned by a WoodEye® scanner and together with dimensions, weight and the first longitudinal resonance frequency, a modulus of elasticity (MOE) profile was calculated for each board. The MOE profiles were calculated according to Olsson et al (2013) i.e. by a transformation matrix based upon the fibres orientation and a compliance matrix based on material parameters for Norway spruce. Secondly, the corresponding MOE profiles were then determined after the boards had been planed. As a result two MOE profiles were determined for each board. An indicating property (IP) was defined as the lowest value along each MOE profile. To compare the results a regression analysis was performed in which the IPs defined before planing worked as predictor variable and IPs defined after planing worked as response variable. The band sawn band boards yielded an R2 = 0.94 and the circular sawn boards an R2 = 0.93. Further the standard error of estimate was SEE = 829.1 MPa and SEE = 640.9 MPa respectively. As a last step in this investigation the SEE values achieved in this study where implemented on to the sample Olsson et al (2013) used in their investigation.
20

Adaptive evolution and demographic history of Norway spruce (Picea abies) /

Källman, Thomas, January 2009 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2009. / Härtill 5 uppsatser.

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