Search results for "SITE"
showing 10 items of 8388 documents
Farming intensity indirectly reduces crop yield through negative effects on agrobiodiversity and key ecological functions
2022
International audience; Farming intensity and landscape heterogeneity influence agrobiodiversity and associated ecological functions. The relative contributions of these agroecosystem components to agricultural production remain unclear because of inter-relations and weather-dependant variations. Using a structural equation modelling approach, we estimated direct and indirect contributions of farming intensity (soil management, pesticide use and fertilisation) and landscape heterogeneity (of semi-natural covers and crop mosaic) to cereal crop production, in 54 fields (mostly wheat), in two years (24 and 30 fields). Indirect effects were evaluated through agrobiodiversity (carabid and plant …
Effect of the extensional flow on the properties of oriented nanocomposite films for twist wrapping
2011
In this study, we examined the mechanical behavior of nanocomposite films based on polyethylene (PE) and pristine PE films. The films were prepared by film blowing and were then cold-drawn at low temperature. The experimental results show that cold drawing significantly enhanced the orientation; with increasing draw ratio (DR), the elastic modulus and tensile strength of the PE films strongly increased, particularly in the presence of the organoclay. To obtain polymeric films suitable for twist wrapping, the films must be sufficiently stiff so that no shrinkage or elastic recovery occur during or after twisting. The elongation at break and the yield strain sharply decreased with orientation…
Ruokapalveluhenkilöstön työn stressitekijät ja hyvinvointi työssä
1999
Urasiirtymät muuttuvassa työelämässä : analyysi urasiirtymän käsitteestä
2012
Työn ja perheen vuorovaikutus : työn stressitekijöiden yhteydet perheen hyvinvointiin
2000
Tutkimus tehostaa suojelutoimia : yhteenveto Puutteellisesti tunnettujen ja uhanalaisten metsälajien tutkimusohjelman vaikuttavuudesta
2017
Non peer reviewed
Woodland key habitats : a key to effective conservation of forest biodiversity?
2011
Prompt Determination of the Mechanical Properties of Industrial Polypropylene Sandwich Pipes
2021
A simple and prompt method to determine the mechanical properties of industrial multilayer extrusion polypropylene pipes for a gravity sewer network is suggested. The engineering formulas included for calculating the permissible thickness and relative position of a foam core in the pipes are based on a linear-elastic approximation and the rule of mixtures. The applicability of the approximation was justified experimentally during investigation of the effective tensile characteristics of single- and multilayer pipes and each layer specimen by using traditional tests and finite-element calculations. The results obtained were used to formulate engineering recommendations for calculations of th…
Influence of uniaxial pressure on dielectric properties of (1- x )Na 0.5 Bi 0.5 TiO 3– x SrTiO 3 for x = 0.01, 0.04, and 0.1 ceramics
2017
The publication costs of this article were covered by the Estonian Academy of Sciences and the University of Tartu.