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Publicatii proprii
Refractive indexes measurement and correlation for selected binary systems of various polarities at 25 0C
New refractive indexes at 25 0C were measured and reported here for 19 binary mixtures of pentan-3-one + 1,2-dichloroethane, + 1,3-dichloropropane, + 1,4-dichlorobutane, + trichloromethane, + 1,1,1-trichloroethane, + 1,1,2,2,-tetrachloroethane, cyclopentanone + 1-chlorobutane, + 1,1,2,2,-tetrachloroethane, cyclohexanone + 1,1,2,2-tetrachloroethane, 5-chloro-2-pentanone + n-hexane, + toluene, + ethylbenzene, nitromethane + trichloromethane and nitromethane
Read moreComputer Aided Study Regarding the Influence of Filling Characteristics on the Longitudinal Reaction within the Body of a Braked Train
This paper describes a computer aided approach to the study of the longitudinal dynamics of a braked train. The numerical simulation of the phenomena takes into account the delay between the braking action of the cars and the fact that the values of the braking force of each wagon is reached gradually, in certain time after the braking command. The values of the time interval elapsed between the braking command and the moment when the nominal braking
Read moreLongitudinal dynamics of Trainsa non-smooth approach
An efficient and straightforward algorithm for the integration of the constrained systems is developed in the present work. Some of the fundamental issues of contact dynamics are briefly reviewed. Considering Gauss’ least constraint principle, an intuitive and effective computation method of the constraint forces is arrived at. The contact problem is solved by means of the generalized matrix inverse (GI) embedded in an appropriate algorithm and
Read moreAlternative Friction Models for Train Braking Dynamics
Braking dynamics plays an essential role in ensuring the comfort and running safety of trains. Due to the complexity of the phenomena involved and the presence of dry friction, studies have been carried out by numerical methods using smoothening. Based on the non-smooth dynamics framework, in the present paper, an efficient and comprehensive alternative model is defined. Set-valued friction of Coulomb's law type is accounted for and motion equations
Read morePhotoelectron spin-flipping and texture manipulation realized in a topological insulator
Recently discovered materials called three-dimensional topological insulators constitute examples of symmetry protected topological states in the absence of applied magnetic fields and cryogenic temperatures. A hallmark characteristic of these non-magnetic bulk insulators is their protected metallic Dirac fermion-like surface states. Electrons in these surface states are spin polarized with their spins governed by their momentum, resulting in a helical
Read moreFinancial stability and monetary policy: a reduced-form model for the Euro area
This paper is related to the growing academic literature on monetary policy and financial stability. In the first part, we propose a review of the literature on the subject, describing both theoretical and empirical models. In the second part, based on Filardo’s approach, we construct a reduced-form model for the Euro Area, addressing the need to include the financial stability objective into the ECB monetary policy decisions. The purpose of the
Read moreEstablishment of rare flood meadow species by plant material transfer: Experimental tests of threshold amounts and the effect of sowing position
The transfer of freshly cut seed-containing plant material is a widely applied method to re-establish grassland of high biodiversity. Still, the amount of plant material applied varies greatly across restoration projects. Therefore, we set up a two-year common garden experiment where we assessed the effect of plant material amount (0, 400, 800, 1600, 3200 g m_2) and relative seed position (on top and beneath a litter layer) on seedling establishment,
Read moreSudden changes in environmental conditions do not increase invasion risk in grassland
After direct habitat transformation, biological invasions are considered to be the second most important threat to biodiversity. A better understanding of the factors affecting invasion success in new areas is crucial, and may provide insight into potential control actions. We hypothesized that invasion risk increases in habitats undergoing a sudden change in the disturbance regime or environmental conditions. For testing this assumption we initiated
Read moreExtreme genetic depauperation and differentiation of both populations and species in Eurasian feather grasses (Stipa)
A highly selfing breeding system affects gene flow, which may have consequences for patterns of genetic variation and differentiation on both the population and species level. Feather grasses (Stipa spp.) are dominant elements of Eurasian steppes that persist in Central Europe in scattered isolated populations that are of great conservation interest. Cleistogamy is common in the Stipa pennata group, the phylogeny of which is largely unresolved. Intraspecific
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