Wyniki wyszukiwania - Biblioteka Nauki

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Environmental modeling in small catchments in the context of climate change: Reda case study

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Walczykiewicz T. , Jakusik E. , Skonieczna M. , Woźniak Ł.

Meteorology Hydrology and Water Management. Research and Operational Applications

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2020

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tom Vol. 8, Iss. 1

98--106

EN

The BONUS MIRACLE project focuses on understanding the of the impact of climate change on water environments, including it’s affects on hydrological regimes and nutrient concentrations. The overall objective of MIRACLE is to initiate a social learning process in collaboration with stakeholders, that can identify new configurations for governance (conceptual, institutional, and practice based) in order to reduce nutrient enrichment and flood risk in the Baltic Sea region. These configurations should be understood as new solutions to protect water resources, ecosystem services and provide win-win solutions. To achieve this environmental modelling of the Reda catchment, Poland, is used as a pilot study for the project. Mathematical models which specified the detailed processes associated with water cycles, including determining interconnections and quantifying variables characteristic to the assessment of the water resource quantity and quality, were found to be useful. Due to the complexity of some models, launching, entering the appropriate data in the correct formats and calibrating the models proved to be challenging. Future developments in the water management sector should concentrate on specific local catchment areas where the application of integrated water resource management principles and the adaptation to climate change are more easily merged with local spatial planning. However, a larger number and higher frequency of measurements would be required.

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Study of selected physical, chemical and biological properties of selected materials intended for contact with human body

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Mrówka M. , Machoczek T. , Jureczko P. , Szymiczek M. , Skonieczna M. , Marcoll Ł.

Polish Journal of Chemical Technology

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2019

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tom Vol. 21, nr 1

1--8

EN

The purpose of the conducted study was to analyse new materials intended for contact with the human body in view of their physical, chemical and biological properties. The authors have put to test six commercially available materials, four out of which were composite polyamide 12-based materials, while two were polyurethanes. The examined materials were assessed in terms of the surface. Subsequently, their hardness and biocompatibility were tested. The authors devoted major attention to the tests of absorption and emissivity of water, the pH = 7.4 PBS buffer solution and pH = 4.3 artificial sweat in temperatures of 21°C and 37°C. The results of the tests have confirmed the non-toxicity of all the tested materials and allowed to provide their characteristics in terms of their surface, hardness, as well as absorption and emissivity of various body fluids. Both polyamide 12 and the tested polyurethanes are classified as thermoplastics that may be used in additive technology.

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The influence of halloysite on the physicochemical, mechanical and biological properties of polyurethane-based nanocomposites

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Mrówka M. , Szymiczek M. , Machoczek T. , Lenża J. , Matusik J. , Sakiewicz P. , Skonieczna M.

Polimery

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2020

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tom T. 65, nr 11-12

784--791

EN

The impact of the addition of the nanofiller – halloysite – on the mechanical, physicochemical and biological properties of a nanocomposite, in which thermoplastic polyurethane fulfilled the role of the matrix was investigated. The nanocomposite was obtained by extrusion in three variants with 1, 2 and 3 wt % halloysite. The nanostructure of the obtained materials was confirmed using Atomic Force Microscopy (AFM). Based on the mechanical tests carried out, it was proven that the obtained nanocomposites were characterized by a tensile modulus greater than the polyurethane constituting the matrix. The density and hardness of the nanocomposites had changed within error limits compared to unmodified polyurethane. Biological tests showed no cytotoxicity of all the tested materials to normal human dermal fibroblasts (NHDF). Degradation tests were carried out in artificial plasma and showed that samples with 2 wt % halloysite addition had the best ratio of tensile strength and elongation at break to elasticity modulus.

PL

Zbadano wpływ naturalnego nanonapełniacza – haloizytu – na właściwości mechaniczne, fizykochemiczne oraz biologiczne kompozytu wytworzonego na bazie termoplastycznego poliuretanu. Nanokompozyt o zawartości 1, 2 i 3% mas. haloizytu otrzymywano na drodze wytłaczania. Nanostrukturę wytworzonych materiałów potwierdzono za pomocą mikroskopii sił atomowych (AFM). Na podstawie przeprowadzonych badań mechanicznych wykazano, że uzyskane nanokompozyty charakteryzują się modułem sprężystości większym niż poliuretan stanowiący osnowę. Zmiany gęstości i twardości niemodyfikowanego poliuretanu po dodaniu haloizytu mieściły się w granicach błędu pomiaru. Testy biologiczne nie wykazały cytotoksyczności wszystkich badanych materiałów wobec prawidłowych fibroblastów ludzkiej skóry (NHDF). Badania degradacji przeprowadzone w środowisku syntetycznego osocza wykazały, że próbki z dodatkiem 2% mas. haloizytu mają najlepszy stosunek wytrzymałości na rozciąganie i wydłużenia przy zerwaniu do modułu sprężystości.