Lulea Technical University

Sweden

Lulea Technical University

Sweden
SEARCH FILTERS
Time filter
Source Type

Mansouri H.R.,University of Lorraine | Mansouri H.R.,University of Zabol | Pizzi A.,University of Lorraine | Leban J.M.,French National Institute for Agricultural Research | And 3 more authors.
Journal of Adhesion Science and Technology | Year: 2011

Linear vibration welding of good quality pine (Pinus sylvestris) wood from Sweden containing a small proportion of a native mixture of terpenoic acids, known under the collective name of rosin, has been shown to yield joints of much upgraded water resistance. This has been shown to be due to the protecting influence the molten rosin from the wood itself has on the welded interphase, because of the water repellency of rosin. Joints of unusually high percentage wood failure but modest strength were obtained, rosin apparently reinforcing the welded interphase to yield weldline strengths always much higher than the strength of the surrounding wood. © Koninklijke Brill NV, Leiden, 2011.


Locat A.,Laval University | Leroueil S.,Laval University | Bernander S.,Lulea Technical University | Demers D.,Section Mouvements de Terrain | And 2 more authors.
Canadian Geotechnical Journal | Year: 2011

Observations from past events are used to show that the concept of progressive failure may explain translational progressive landslides and spreads - large landslides occurring in sensitive clays. During progressive failure, the strain-softening behaviour of the soil causes unstable forces to propagate a failure surface further in the slope. Translational progressive landslides generally take place in long, gently inclined slopes. Instability in a steeper upslope area is followed by redistribution of stress, which increases earth pressure further downslope. Passive failure may therefore occur in less-inclined ground, heaving the soil. Spreads are usually trigged by erosion of a deposit having a higher angle near the toe. Instability starts near the toe of the slope and propagates into the deposit, reducing earth pressure. This may lead to the formation of an active failure with dislocation of the deposit into horsts and grabens. The failure mechanism of both types of landslides is controlled by the stresses in the slope and the stress-strain behaviour of the soil. The mechanism presented explains the sensitivity of a slope to minor disturbances and the resulting high retrogressions observed for such landslides in Scandinavia and eastern Canada.


Sakharova A.V.,Kazan Federal University | Filippov A.V.,Kazan Federal University | Munavirov B.V.,Kazan Federal University | Skirda V.D.,Lulea Technical University
Russian Journal of Physical Chemistry A | Year: 2011

Transverse relaxation and self-diffusion of molecules in a glyceryl monooleate (monoolein)-D2O system was studied using pulsed 1H NMR in a range of water concentrations from 10 to 30 wt % and a range of temperatures from 20 to 90°C. It was noted that self-diffusion is described by one or two self-diffusion coefficients, depending on the temperature and concentration of water, while NMR-relaxation has a complex form. It was determined that with a reduction in the transverse magnetization, a component that has a form similar to Gaussian and relaxation times of 70 to 250 j, s is observed at certain temperatures and concentrations of water, confirming the formation of structures in which glyceryl monooleate molecules (GM) are characterized by anisotropic rotational mobility. It was demonstrated that the ranges of the concentrations of water and temperature in which this component is observed correspond to liquid-crystalline phase for lamellar and inverse hexagonal structural organizations of lipids, according to the state diagram obtained by X-ray diffraction. In the state diagram areas corresponding to micellar and cubic structures (characterized by the isotropic rotation of GM molecules in the time scale of NMR), multiexponential decays of magnetization with average relaxation times were noted in the range of 10 to 200 ms. A number of features were discovered with the use of NMR: specimens always contain structures with isotropic rotational mobility in the presence of structures characterized by anisotropic rotational mobility; a change in the fraction of the structures with anisotropic rotational mobility takes place slowly over 5-15 K, not abruptly. Our conclusions regarding the polymorphism of a GM-D2O system in the presence of anisotropic structures was confirmed by an analysis of the transverse NMR relaxation in an egg phosphatidylcholine-D2O system, for which the presence of only lamellar liquid-crystalline structure is confirmed by 31P NMR. © Pleiades Publishing, Ltd., 2011.

Loading Lulea Technical University collaborators
Loading Lulea Technical University collaborators