Time filter

Source Type

Lublin, Poland

Maria Curie-Skłodowska University was founded October 23, 1944 in Lublin. It is named in honour of Marie Curie-Sklodowska.Currently the number of students is almost 36,000. The university has 302 professors , 231 habilitated doctors, 826 senior lecturers, and 1829 teachers in total. Total staff is 3628.To meet the growing demand for higher education, the university has established branches in other cities. Wikipedia.

Wardak C.,Maria Curie Sklodowska University
Journal of Hazardous Materials | Year: 2011

A new polyvinylchloride membrane sensor for Pb2+ with solid contact based on ionic liquid has been prepared. The electrode shows a Nernstian response for lead ions over a wide concentration range (1×10-8 to 1×10-1molL-1) and the slope of 29.8mV/decade. The limit of detection is 4.3×10-9molL-1. It has a fast response time of 5-7s and can be used for 4 months without any divergence in potential. The proposed sensor is not pH sensitive in the range 3.5-7.3 and shows a very good discriminating ability towards Pb2+ ion in comparison with some alkali, alkaline earth, transition and heavy metal ions. It was successfully applied as an indicator electrode in potentiometric titration of lead ions with K2CrO4 and for direct determination of Pb2+ ions in real sample solution. © 2010 Elsevier B.V.

In the article, a new integrated kinetic Langmuir equation (IKL) is derived. The IKL equation is a simple and easy to analyze but complete analytical solution of the kinetic Langmuir model. The IKL is compared with the nth-order, mixed 1,2-order, and multiexponential kinetic equations. The impact of both equilibrium coverage θ eq and relative equilibrium uptake u eq on kinetics is explained.Anewly introduced Langmuir batch equilibrium factor f eq that is the product of both parameters θ equ eq is used to determine the general kinetic behavior. The analysis of the IKL equation allows us to understand fully the Langmuir kinetics and explains its relation with respect to the empirical pseudo-first-order (PFO, i.e., Lagergren), pseudo-second-order (PSO), and mixed 1,2-order kinetic equations, and it shows the conditions of their possible application based on the Langmuir model. The dependence of the initial adsorption rate on the system properties is analyzed and compared to the earlier published approximate equations. © 2010 American Chemical Society.

Kloskowski J.,Maria Curie Sklodowska University
Oikos | Year: 2012

In anthropogenic landscapes animals may be lured into low-quality habitats where they survive or reproduce poorly ('ecological traps'). I investigated breeding habitat selection in relation to intra-seasonal changes in food availability and reproductive output in red-necked grebes Podiceps grisegena, a size-limited predator, of common carp Cyprinus carpio ponds. Carp farms constitute highly heterogeneous habitat mosaics due to separate stocking of different age/size fish. Pond features significant for grebe settling decisions, i.e. hydroperiod and emergent vegetation cover, had no obvious effects on prey abundance for chicks and on fledging success. Breeding grebes avoided ponds containing fish too large for them to ingest but exhibited little preference between ponds with medium-sized one-year-old carp that could be exploited by pre-laying birds, and ponds designated for young-of-the-year carp, where only invertebrates and amphibians were available as prey in early spring. Red-necked grebes settling on ponds with medium-sized fish failed to predict future shifts in interactions with carp stocks; carp exceeded the prey-size threshold of chicks and adversely affected their non-fish prey levels. The resulting food shortage led to severe egg-to-fledging mortality rates compared to fishless ponds or those containing young-of-the-year fish. This study shows that waterbirds vulnerable to competition from fish can risk maladaptive habitat selection due to unrecognised spatial and temporal variation in food resources caused by fish stocking practices. Ecological traps created by perturbations to trophic interactions may be common but difficult to detect because altered dynamics of trophic resources can affect wildlife indirectly. As with other types of ecological traps, manipulation of habitat features identified as attractive cues for settling animals, but not related to critical food resources, may help to reduce perceptual pitfalls. For example, wetland management to mitigate trap effects driven by commercially stocked fish should preserve abundant emergent vegetation in habitats with weak fish impact and extend their hydroperiod. © 2012 The Authors.

Rogatko M.,Maria Curie Sklodowska University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

Making use of the conformal positive energy theorem, we prove the uniqueness of four-dimensional static electrically charged black holes being the solution of Chern-Simons modified gravity equations of motion. We assume that black hole spacetime contains an asymptotically flat spacelike hypersurface with compact interior and nondegenerate components of the event horizon. © 2013 American Physical Society.

Jurak M.,Maria Curie Sklodowska University
Journal of Physical Chemistry B | Year: 2013

Cholesterol is an important component of lipid rafts in mammalian cell membranes. Studies of phospholipid monolayers containing cholesterol provide insight into the role of cholesterol in regulating the properties of animal cells, raft stability, and organization. In this contribution, a study of the characteristics of binary Langmuir monolayers consisting of phospholipids, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), 1,2-dioleoyl-sn-glycero-3- phosphocholine (DOPC), 2-oleoyl-1-palmitoyl-sn-glycero-3-phosphocholine (POPC), 1,2-dipalmitoyl-sn-glycero-3-phospho-rac-(1-glycerol) (DPPG), and cholesterol (Chol), was conducted on the basis of the surface pressure-area per molecule (π-A) isotherms. Analysis of the results obtained provided information on the mean molecular area, the excess Gibbs energy of mixing, and condensation in the monolayer. The mixed monolayers were also deposited onto the mica plates and investigated by the contact angle measurements of water, formamide, and diiodomethane. The contact angles allowed calculating surface free energy of the films from the van Oss et al. approach. It was found that cholesterol determines the molecular packing and ordering of the monolayers closely connected with the kind of phospholipid. This is reflected in the values of surface free energy of the model membranes. From the thermodynamic analysis of phospholipid/cholesterol/liquid interactions, one may draw conclusions about the most favorable composition (stoichiometry) of the binary film which is especially important in view of the lipid rafts formation. © 2013 American Chemical Society.

Discover hidden collaborations