Wyniki wyszukiwania - BazTech

1

The influence of sterilization on properties of polyurethane/polylactide blend

Bednarz P., Bernasik A., Laska J.

Science, Technology and Innovation

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2018

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Vol. 2, no. 1

13--18

EN

The biodegradable polyurethane/polylactide blend was treated with low temperature hydrogen peroxide plasma, ethylene oxide and immersing in ethanol combined with ultraviolet radiation. The samples sterilized by hydrogen peroxide and ethylene oxide stood practically unaffected, while UV/EtOH caused distinct changes in their mechanical properties. For example the significant reduction of tensile strength occurred, elongation at break became twice lower, while the Young’s modulus increased by 23%. The XPS measurements showed that after all types of treatment atomic carbon and nitrogen concentrations in the surface layer was slightly lower than in the bulk. Instead the surface layer was more enriched with oxygen. Ethylene oxide sterilization caused that both surfaces became more hydrophobic i.e. the contact angle increased about 15% for the top surface and 8% for the bottom surface, respectively. Sterilization with ethanol and UV radiation changed the nature of surface into more hydrophilic, the contact angle of the top surface was reduced about 6% and the bottom about 24%. The FT-IR spectra of all sterilized samples were recorded and discussed. From all used sterilization methods only hydrogen peroxide plasma is fully suitable for biodegradable PU/PLA blend.

2

Fabrication, properties and cytotoxicity evaluation of degradable poly(trimethylene carbonate-co-lactide) for the use as nerve guidance channels

Bednarz P.

Tarnowskie Colloquia Naukowe. Nauki Techniczne i Ścisłe

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2017

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T. 4, nr 3

39--48

EN

Strategies to improve healing of damaged nerves include the application of specialized nerve guides, which hold the promise for allowing reanastomosis of the severed or damaged fibers. Studies have demonstrated that the use of a slowly degradable polymeric nerve guide can improve the nature and rate of nerve regeneration across a short gap in small nerves. The objective of this study was to characterize a biodegradable nerve guide based on poly(trimethylene carbonate-co-lactide) for peripheral nerve regeneration and to evaluate its cytotoxicity. The obtained copolymer films were incubated in two different media (distilled water and simulated body fluid), and while the degradation process appeared, pH and ion conductivity changes of solutions were monitored as well as mass loss of the samples. Additionally, mechanical tests (tensile strength, elongation at break and Young’s modulus parameters) before and after different time points were carried out. To evaluate cytotoxicity biological test were done on fibroblasts cells (NIH 3T3). Cell metabolic activity was determined using Alamar Blue reagent and their morphology was observed under fluorescence microscopy. The growth of pH in both media were mostly caused by steadily degradation of carbonate units into alkaline diols. The growth of ion conductivity value at the beginning of the incubation process was associated with the releasing of free ions to the solution. The mechanical parameters decreased with the progress of degradation process. Ringer’s fluid, as more aggressive, caused higher decrease in mechanical properties. The measured contact angles showed good surface wettability. Both surfaces, the top and the bottom, had similar hydrophilicity. Moreover, activity of fibroblasts cells were similar on both sides as well as on the reference TCPS. Good adhesion of NIH 3T3 cells to the surface suggests that the hydrophilic polymers promote colonization of fibroblasts cells on their surface. Biological studies have shown that used cells are very sensitive to surface topography which they colonize and cell viability was higher at the bottom surface, which has a slightly higher average roughness Ra. Thus, fibroblasts cell preferred colonizing rougher than smoother surfaces. Fabricated films does not affect negatively, namely, toxic on cell cultures and forms substrate with favourable surface properties. This was confirmed by the Alamar Blue tests and microscopic observations.

3

Hydrogen peroxide/UV treatment on polylactide/polyurethane blends for biomedical applications

Bednarz P.

Science, Technology and Innovation

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2017

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Vol. 1, no. 1

44--48

EN

Biodegradable polymers should be non-toxic, possess low immunogenicity and good mechanical properties. Due to their hydrophobicity and their low surface energy cells only poorly attach, spread and proliferate on these biodegradable polyesters. Therefore, the surface of these polyesters should usually be modified and already several approaches have been presented to increase their cell affinity. In this research the influence of hydrogen peroxide combined with ultra violet irradiation on wettability, morphology and mechanical properties of PU/PLA blends as well as their pure components. It was clearly visible that both pure PU and PLA acted completely different form PU/PLA blend during treatment. The wettability of pure polymers changed after H2O2/UV, PU surface became more hydrophilic, whereas PLA becomes slightly hydrophobic. Due to micropores and microcracks visible on surfaces resulted from breaking ester linkage, deterioration of their mechanical properties was also observed. The exposure of PU/PLA films to H2O2/UV irradiation showed the change of wettability toward more hydrophilic and increase of mechanical properties because of specific affinity to the etching process.

4

Wykorzystanie technologii RFID w monitorowaniu temperatury - system BLULOG

Bednarz P., Popiel J.

Journal of TransLogistics

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2017

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Vol. 3, nr 2

191--198

PL

Celem głównym artykułu jest obliczenie, ile pieniędzy można zaoszczędzić wykorzystując fale radiowe RFID do pomiaru temperatury w łańcuchu logistycznym. Ponadto wyznaczono cele pomocnicze: określenie zalet i wad tej technologii, a także potencjalnych użytkowników i możliwych zastosowań. Do badania wykorzystano metodę tabelaryczną. Ostatecznie autorzy dokonali kalkulacji, jakie koszty są ponoszone przez marnowanie produktów, które były przechowywane w złych warunkach termicznych. Wyniki przedstawionego badania opatrzono szczegółowym opisem.

EN

The main goal of this article is to calculate how much money is possible to save thanks to the RFID. Moreover, the authors set up some additional goals: to identify advantages, disadvantages and the potential users. For this research, the authors used the table which presents the cost of the food thrown due to the fact that they had been stored improperly. Additionally, the results are described by detailed description.

5

Materials and methods supporting nerve regeneration in peripheral and central nervous system

Laska J., Bednarz P., Lis A., Szarek D.

Engineering of Biomaterials

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2014

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Vol. 17, no. 128-129

95--96

6

Enhanced Oil Recovery methods on offshore fields in the light of world literature

Bednarz P., Stopa J.

AGH Drilling, Oil, Gas

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2014

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Vol. 31, no. 2

215--229

EN

Enhanced Oil Recovery methods (EOR) are known since long time, but in recent years they have been used primarily in the U.S. mostly for research purposes. The increased interest in their use was in the 70's of the twentieth century, and associated with the increase in oil prices. Currently for several years there has been a return to the these methods, including offshore fields. Experience in the application of EOR methods in Poland is small, currently no exploitation is carried out using them. The purpose of this article is to present the current trends and latest technologies in enhanced oil recovery methods in terms of the applicability by the Polish oil companies. Statistical data of current and planned EOR methods in the world with special emphasis on offshore reservoirs is presented. Current trends in technological development of EOR methods are given, both which are still in the phase of laboratory tests and the first tests on fields such as: carbon dioxide flooding, water alternating gas injection, Iow salinity water injection, carbonated water injection, conventional technologies of polymer gels and thermally activated polymers.

7

Minęło 100 lat eksploatacji zbiornika wodnego Pilchowice na Bobrze. Część II

Machajski J., Bednarz P., Sidor S.

Gospodarka Wodna

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2013

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Nr 10

393--398

PL

W artykule przedstawiono historię budowy i eksploatacji zbiornika wodnego Pilchowice na rzece Bóbr. Obiekt przez ponad sto lat użytkowania dorobił się bardzo bogatej historii. Historię budowy zbiornika przedstawiono w nawiązaniu do złożonej hydrologii rzeki Bóbr, omawiając większe wezbrania powodziowe, jak również obowiązujące dla przekroju lokalizacji zbiornika przepływy charakterystyczne. Wskazano wiele problemów eksploatacyjnych obiektu, wynikających nie tylko ze starzenia się obiektu, ale również z braku możliwości pełnego sterowania przejściem wezbrań powodziowych przez zbiornik. Poruszono problematykę wyposażenia obiektu w urządzenia pomiarowo-kontrolne, jak również omówiono niektóre wyniki pomiarów przemieszczeń pionowych, poziomych czy wyniki pomiarów piezometrycznych zjawisk filtracyjnych zarówno w korpusie zapory, jak również w podłożu w rejonie jej posadowienia.

EN

The authors indicate numerous problems with exploitation of the facility, resulting not only from its ageing, but also from the lack of possibility to fully control the flood wave passage. They also discuss problems connected with the issue of equipping the reservoir with control and measurement devices, as well as some results of vertical and horizontal dislocations or the piezometric measurements of filtration phenomena in the dam’s body and in the subsoil near its foundations.

8

Minęło 100 lat eksploatacji zbiornika wodnego Pilchowice na Bobrze

Machajski J., Bednarz P., Sidor S.

Gospodarka Wodna

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2013

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Nr 9

351--358

PL

W artykule przedstawiono historię budowy i eksploatacji zbiornika wodnego Pilchowice na rzece Bóbr. Obiekt przez ponad sto lat użytkowania dorobił się bardzo bogatej historii. Historię budowy zbiornika przedstawiono w nawiązaniu do złożonej hydrologii rzeki Bóbr, omawiając większe wezbrania powodziowe, jak również obowiązujące dla przekroju lokalizacji zbiornika przepływy charakterystyczne. Wskazano wiele problemów eksploatacyjnych obiektu, wynikających nie tylko ze starzenia się obiektu, ale również z braku możliwości pełnego sterowania przejściem wezbrań powodziowych przez zbiornik. Poruszono problematykę wyposażenia obiektu w urządzenia pomiarowo-kontrolne, jak również omówiono niektóre wyniki pomiarów przemieszczeń pionowych, poziomych czy wyniki pomiarów piezometrycznych zjawisk filtracyjnych zarówno w korpusie zapory, jak również w podłożu w rejonie jej posadowienia.

EN

The article presents the rich 100-year history of construction and exploitation of the Pilchowice reservoir on the Bóbr . It shows the reservoir's history in the context of the Bóbr mpl hydrology, discussing largest floods and current characteristic flows for the reservoir’s cross-section. The authors indicate numerous problems with exploitation of the facility, resulting not only from its ageing, but also from the lack of possibility to fully control the flood wave passage. They also dis-cuss problems connected with the issue of equipping the reservoir with control and measurement devices, as well as some results of vertical and horizontal dislocations or the piezometric measure-ments of filtration phenomena in the dam’s body and in the subsoil near its foundations.

9

Influence of surface topography and morphology of PU/PLA films on fibroblasts performance

Bednarz P., Krok M., Laska J.

Engineering of Biomaterials

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2012

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Vol. 15, no. 116-117 spec. iss.

120--122

10

Id polymer composites for medical application

Szaraniec B., Ziąbka M., Bednarz P., Chłopek J.

Polish Journal of Applied Chemistry

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2009

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Vol. 53, nr 3

253-258

EN

The work concerns ID composites with resorbable polymer (poly-UDL-laetidc) matrix which can be used as medical implants. Composites were reinforced with three types of long fibers such as carbon, polyacrylonitrile, and alginate. The samples were produced in two-stages process: composite films casting and hot press moulding. Obtained paddles were incubated in distilled water. Mechanical properties (tensile strength, Young modulus) of the samples before and after different incubation time were measured. On the basis of pH and conductivity changes of water during compositcs incubation the degradation rate was investigated. Additionally the morphology of the surface were evaluated. The composites significantly differed in mechanical properties and degradation rate.

11

Degradacja mieszanin polimerowych poliuretanu z polilaktydem w symulowanym środowisku biologicznym

Gajowy J., Bednarz P., Laska J.

Engineering of Biomaterials

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2009

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Vol. 12, no. 89-91

213--216

PL

W niniejszej pracy przedstawiono wyniki szczegółowych badań degradacji mieszaniny poliuretanu i poli(L-laktyd-co-DL-laktydu) PU/PLDL w symulowanym środowisku biologicznym. Mieszanina o takim składzie charakteryzuje się bardzo dobrą poręcznością chirurgiczną, tj. można uzyskiwać cienkie, elastyczne i wytrzymałe folie, łatwe do przyszycia do tkanki żywej. Proces biodegradacji był badany poprzez inkubację sześciennych próbki o boku 1m w wodzie destylowanej i płynie Ringera w temp. 37oC przez okres 4 miesięcy i obserwację zmian pH, przewodnictwa, ubytku masy oraz czasu przejścia fali ultradźwiękowej.

EN

In this work results of detailed research on polymer mixture of polyurethane and poly(L-lactide-co-DL-lactide) PU/PLDL in simulated biological environment are presented. The mixture of this composition can be easily manoeuvred during the surgery, i.e., thin, elastic, mechanically resistant and suture convenient films can be manufactured. Samples of cubical shape with all three dimensions of 1cm were incubated in water and Ringer’s fluid for four months, and concurrently measurements of pH, conductivity, loss of mass and time of ultrasonic wave passing were carried out.

12

Dwuletni okres eksploatacji ASTKZ na zaporze Pilchowice

Beynar-Czeczott E., Lebiecki P., Żebrowska A., Bednarz P.

Gospodarka Wodna

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2000

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Nr 2

73-74

PL

Przedstawiono charakterystykę systemu ASTKZ zainstalowanego na zaporze w Pilchowicach, wraz z opisem rozmieszczenia i rozmieszczenia i charakterystyką urządzeń pomiarowych. Dokonano oceny pracy systemu wlatach 1996-1997.

EN

he characteristic of the system ASTKZ of the Pilchowice dam inclusive of description of distribution and characteristic of measuring instruments have been presented. The paper presents also estimation of the work of the system in the years 1996-1997.

13

Zapora Pilchowice I - stan techniczny

Beynar-Czeczott E., Lebiecki P., Żebrowska A., Bednarz P.

Gospodarka Wodna

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1999

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Nr 12

421-424

PL

Prowadzone od lat sześćdziesiątych badania i pomiary eksploatowanej od 1913 r. zapory Pilchowice wskazują na pogarszanie się stanu technicznego obiektu. Omówiono wyniki prac badawczych w zakresie filtracji przez podłoże i zaporę oraz wytrzymałosci materiału korpusu zapory i podłoza. Dokonano oceny stanu bezpieczeństwa zapory Pilchowice.

EN

The carried on since the 1960s investigations and measurements of the dam Pilchowice which has been utilized since the year 1913 indicate to the worsening of the technical state of that object. The paper discusses results of the research works concerning filtration through the subsoil and through the dam as well as the strength of the body and the subsoil of the dam. It presents also estimation of the safety state of the dam Pilchowice.