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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2009

Abstract

A series of comparable specimens of spruce wood were submitted to chemical pre-treatments. Chemical pre-treatments were carried out with diluted sodium hydroxide, or sodium hydroxide and then by hydrogen peroxide, or per-acetic acid. All pre-treatments modified the chemical composition of wood and led to its weight loss. The pre-treatments resulted in a complete deacetylation, and partial delignification of wood and did not cause apparent loss of cellulose. Chemical alterations of the pre-treated spruce wood were markedly reflected in its improved digestibility under conditions of kraft cook. The obtained pulps were characterized with apparently reduced content of residual lignin, lower yield, moderate drop in DP, higher brightness and better optical properties (colour and lightness) of both unbleached and bleached pulps.

Abstract

This paper describes briefly the phenomena of alternate bearing of European plums and point out that more detailed investigations about physiological factors, in particular plant hormones, involved in the flowering process are of great importance.

Abstract

One of the biggest drawbacks of using European native wood species as a construction material is its tendency to degrade by fungal attack. This has lead to the development of different systems for wood preservation. Many of these systems suffer the disadvantage that they contain biocides, which can leach from the wood into the environment and damage organisms. In this project ten silanes, 3-(2-Aminoethylamino)propyltrimethoxysilane, 3-[2-(2- aminoethylamino)ethylamino]propyltrimethoxysilane, 3-Aminopropyltrimethoxysilane, Diethoxydimethylsilane, Dodecyltriethoxysilane, Hexadecyltrimethoxysilane, NTrimethoxysilylpropyl- N,N,N-trimethylammoniumchloride, Octyltriethoxysilane, Octyltrimethoxysilane and Phenyltrimethoxysilane, have been investigated for their ability to increase the hydrophobicity of wood and decrease shrinking and swelling, and thus increase its ability to withstand attack by fungi. In the initial phase of the project two solvents, ethanol and water were investigated to find out which of these that gave the best result for surface modification with silanes. The results showed that water as solvent gave a surface with higher hydrofobicity than when ethanol was used as solvent....

Abstract

A cost efficient use of harvesting resources is important in the forest industry. The main planning is made in an annual resource plan which is continuously revised. The harvesting operations are divided into harvesting and forwarding. The harvesting operation fells trees and put them in piles in the harvest areas. The forwarding operation collects piles and moves them to storage locations adjacent to forest roads. These operations are done by machines (harvesters, forwarders and harwarders) and these are operated by crews living in cities/villages which are within some maximum distance from the harvest areas. Machines, harvest teams and harvest areas have different characteristic and properties and it is difficult to come up with the best possible match throughout the year. The aim with the planning is to come up with a cost efficient plan The total cost is based on three parts; production cost, traveling cost and moving cost. The production cost is the cost for the harvesting and the forwarding. The traveling cost is the cost for driving back and forward (daily) to the harvest area from the home base. Moving cost is associated with moving the machines and equipment between harvest areas. The Forest Research Institute of Sweden has together with a number of Swedish forest companies developed a decision support platform for the planning. An important aspect is to come up with high quality plans within short computational time. A central part is an optimization model which integrates assignment of machines to harvest areas and scheduling of the harvest areas during the year for each machine. The problem is complex and we propose a two phase solution method where we first solve the assignment problem and in a second stage the scheduling. In order be able to control the scheduling also in phase 1, we have introduced an extra cost component which balances the geographical spread of the assignments in phase 1. We have tested the solution approach on a case study from one of the larger Swedish forest companies. This case study involves 46 machines and 968 harvest areas representing a log volume of 1,33 million cubic meters. We describe some numerical results and experiences from the development and tests.