| 1. |
- Eriksson, P, et al.
(författare)
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Neonatal exposure to DDT and its fatty acid conjugate: effects on cholinergic and behavioural variables in the adult mouse
- 1990
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Ingår i: NeuroToxicology. - 1872-9711. ; 11:2, s. 345-354
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Tidskriftsartikel (refereegranskat)abstract
- We have recently observed that DDT and a DDT metabolite, DDOH, conjugated to a fatty acid, palmitic acid, DDOH-PA, affects muscarinic cholinergic receptors (MAChR) in the neonatal mouse brain when given to suckling mice during rapid brain growth. This early exposure of the neonatal mouse also affects the behaviour of the animals as adults. When DDT and DDOH-PA was given as a single low oral dose of 1.4 mumol/kg body weight, DDT (0.5 mg), DDOH-PA (0.7 mg) and a 20% fat emulsion vehicle (10 ml) per kg body weight to 10-day-old NMRI mice, behavioural tests at adult age of four months, indicated disruption of a simple, non-associative learning process, i.e. habituation, in both DDT and DDOH-PA treated mice. There was also a significant increase in the potassium evoked release of ACh from slices of cerebral cortex and a tendency towards a decrease in the density of MAChR in mice receiving DDT. These effects in the adult mice could not be correlated to the concentration of DDT in the adult brain since DDT one month after its administration to the 10-day-old mouse no longer is present in the brain.
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| 2. |
- Dannetun, Per, et al.
(författare)
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Proceedings of the International Conference on Science and Technology of Synthetic Metals The chemical and electronic structure of the interface between aluminum and conjugated polymers or molecules
- 1993
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Ingår i: Synthetic metals. - : Elsevier. - 0379-6779 .- 1879-3290. ; 55:1, s. 212-217
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Tidskriftsartikel (refereegranskat)abstract
- The interaction between aluminum and α-ω-diphenyltetradecaheptaenee (DP7), α-sexithienyl (6T), and poly(p-phenylenevinylene) (PPV), respectively have been studied using both X-ray Photoelectron Spectroscopy (XPS) and Ultraviolet Photoelectron Spectroscopy (UPS). The UPS valence band spectra, are interpreted with the help of quantum chemical calculations based upon Modified Neglect of Diatomic Overlap (MNDO), Valence Effective Hamitonian (VEH) and ab initio Hartree-Fock methods. DP7 is a model molecule for polyacetylene, while 6T is a model molecule (an oligomer) of polythiophene. The results indicate that aluminum reacts strongly with the surfaces of all of the materials studied. The π-electronic structure of each material was strongly modified. Furthermore, aluminum reacts preferentially with the polyene partof DP7, with the vinylene part of PPV, and with the α-carbons of the thiophene nits of 6T.
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| 3. |
- Jarfors, A., et al.
(författare)
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On the thermodynamics and kinetics of carbides in the aluminium-rich corner of the AlTiC phase diagram
- 1991
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Ingår i: Materials Science & Engineering. - 0921-5093 .- 1873-4936. ; 135:C, s. 119-123
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Tidskriftsartikel (refereegranskat)abstract
- Aluminium composites have a great potential because of their high strength-to-weight ratio. Carbides will in the future be powerful reinforcements. To be able to manufacture these it is of importance to know the thermodynamic properties and the kinetic limitations. The objective of this investigation is to study the equilibria between the carbides occurring in the AlTiC system as well as the initial precipitation and dissolution behaviour of these carbides. It can be shown that there is a change in stability between TiC and Al4C3, depending on both composition and temperature. To study the nucleation and precipitation behaviour of the carbides in liquid aluminium and aluminium alloys a set of alloys were melted and heated to an appropriate temperature in graphite crucibles. The effect of time and the effect of composition on the chemical reactions involving carbides have been investigated. A theoretical analysis of both the thermodynamics and kinetics was performed, giving a tentative explanation. © 1991.
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