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.
2016
Abstract
Due to more restrictive toxicological requirements and increased ecological awareness of consumers, wood preservatives containing harmful biocides are no longer desired on the market. Therefore, research on new environmentally friendly formulations is of great importance. One of the possible solutions is to develop new preservatives based on natural substances, which are harmless to humans, animals and the environment, while biologically active. The aim of the study was to develop new biocide-free preservative systems which increase wood resistance to wood-decaying fungi. The following silanes: [3-(2-Aminoethylamino)propyl]trimethoxysilane (AATMOS), (Aminopropyl)triethoxysilane (APTEOS), and (Aminopropyl)trimethoxysilane (APTMOS); caffeine, natural oils and potassium carbonate were chosen as components of new protective formulations, which were planned to be an alternative for traditionally used biocides. Samples of three different wood species (pine, spruce, and poplar) were treated with the new preservative systems and exposed to the brown-rot fungus Coniophora puteana and the white-rot fungus Coriolus versicolor according to EN-113 and EN-839 standards. The obtained results show that wood treated with the water-based formulation consisting of silanes and caffeine (2% caffeine + 5% AATMOS, 2% caffeine + 5% APTEOS) demonstrated the highest resistance to the test fungi. Wood mass loss after exposure to the decay fungi was 1%. All wood species treated with this formulation achieved index 1 (“very resistant”) within durability class acc. to the EN350 standard.
Authors
Attila Nemes Annette Dathe Matthew Patterson Daniel Gimenez Johannes Koestel Esther Bloem Nicholas Jarvis Helen FrenchAbstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
Nonylphenols (NP) are a group of alkylphenols, formed upon degradation of nonylphenol ethoxylates such as nonylphenol monoethoxylate (NP1EO) or nonylphenol diethoxylate (NP2EO), which have been broadly used as non-ionic surfactants. Both NP and their ethoxylates are often present in the sewage, despite being banned and substituted by less toxic alcohol ethoxylates in many countries. There is a number of degradation studies of nonylphenol in the soil environment, but there is a lack of understanding on how plants and soil organisms such as earthworms can affect the degradation. In our study, we investigated the degradation of 4-nonylphenol (4-NP) in a mineral field soil in the presence of barley (Hordeum vulgare) and earthworms (Aporrectodea caliginosa). Soil was spiked with 4-NP at a concentration of 12.5 mg kg-1 d.w. soil. Results showed that the degradation of 4-NP in soil was rapid during the 28 days after spiking, with remaining concentration of 0.397 mg kg-1 d.w. soil on day 28. Degradation was much slower between days 28 and 120, with a remaining concentration of 0.214 mg kg-1 d.w. soil on day 120. No significant difference in the degradation of 4-NP in the presence of either plants or worms was observed, but sampling after 28 days of exposure revealed transfer of 4-NP to worms (worm tissue concentration = 0.79 μg g-1), which increased with time (1.66 μg g-1 after 120 d). The calculated transfer factor after 28 (TF28) and 120 days (TF120) was 0.07 and 0.13 respectively. No toxicity or accumulation in plants was observed at the concentration tested herein. Concentration of 4-NP in the rhizosphere was not statistically different from that in the bulk soil.
Authors
Trine EggenAbstract
No abstract has been registered
Authors
Signe Nybø Bård Pedersen Olav Skarpaas Iulie Aslaksen Jarle W. Bjerke Gregoire Certain Hanne Edvardsen Erik Framstad Per Arild Garnåsjordet Aksel Granhus Hege Gundersen Snorre Henriksen Knut Anders Hovstad Anders Jelmert Margaret McBride Ann Norderhaug Geir Ottersen Eivind Oug Hans-Christian Pedersen Ann Kristin Schartau Ken Olaf Storaunet Gro Ingleid van der MeerenAbstract
No abstract has been registered
Abstract
Several species of microalgae and phototrophic bacteria are able to produce hydrogen under certain conditions. A range of different photobioreactor systems have been used by different research groups for lab-scale hydrogen production experiments, and some few attempts have been made to upscale the hydrogen production process. Even though a photobioreactor system for hydrogen production does require special construction properties (e.g., hydrogen tight, mixing by other means than bubbling with air), only very few attempts have been made to design photobioreactors specifically for the purpose of hydrogen production. We have constructed a flat panel photobioreactor system that can be used in two modes: either for the cultivation of phototrophic microorganisms (upright and bubbling) or for the production of hydrogen or other anaerobic products (mixing by “rocking motion”). Special emphasis has been taken to avoid any hydrogen leakages, both by means of constructional and material choices. The flat plate photobioreactor system is controlled by a custom-built control system that can log and control temperature, pH, and optical density and additionally log the amount of produced gas and dissolved oxygen concentration. This paper summarizes the status in the field of photobioreactors for hydrogen production and describes in detail the design and construction of a purpose-built flat panel photobioreactor system, optimized for hydrogen production in terms of structural functionality, durability, performance, and selection of materials. The motivations for the choices made during the design process and advantages/disadvantages of previous designs are discussed.
Abstract
No abstract has been registered
Authors
Ibrahim Tahir Eivind VangdalAbstract
No abstract has been registered
Abstract
Oidium neolycopersici, the cause of powdery mildew in tomato, was exposed to UV radiation from 250 to 400 nm for 1, 12, or 24 min. Radiation ≤ 280 nm strongly reduced conidial germination, hyphal expansion, penetration attempt and infection of O. neolycopersici. From 290 to 310 nm the effect depended on duration of exposure, while there was no effect ≥310 nm. There were no significant differences within the effective UV range (250–280 nm). Conidial germination on a water agar surface was b20% or around 40%, respectively, if samples were exposed for 1 min within the effective UV range followed by 24 h or 48 h incubation. Twelve or 24 min exposure reduced germination to close to nil. A similar trend occurred for germination of conidia on leaf disks on water agar in Petri dishes. The effective UV range significantly reduced all subsequent developmental stages of O. neolycopersici. There was no cytoplasmic mitochondrial streaming in conidia exposed to the effective UV range, indicating that there may be a direct effect via cell cycle arrest. There was no indication of reactive oxygen species involvement in UV mediated inhibition of O. neolycopersici. Optical properties of O. neolycopersici indicat- ed that the relative absorption of UV was high within the range of 250 to 320 nm, and very low within the range of 340 to 400 nm. Identification of UV wavelengths effective against O. neolycopersici provides a future basis for precise disease control.