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1
Content available Drug - eluting bioresorbable vascular stents manufactured by microinjection moulding
Dobrzyński P., Sobota M., Włodarczyk J., Stoiko M., Pastusiak M., Kasperczyk J., Milewski K., Krauze A.
Engineering of Biomaterials
|
2018
|
Vol. 21, no. 148
33
2
Content available Studium teoretyczne przewidywania ryzyka wystąpienia rozgorzenia, wstecznego ciągu płomieni oraz zapalenia gazów pożarowych
Krauze A., Krasuski A., Ślęczkowski B.
Bezpieczeństwo i Technika Pożarnicza
|
2016
|
Vol. 42, nr 2
87--94
PL
Cel: Niniejszy artykuł opisuje zjawiska występujące podczas przebiegu pożarów wewnętrznych. Szczególną uwagę poświęcono mechanizmowi powstawania wstecznego ciągu płomieni oraz rozgorzenia. Zaprezentowano również możliwości ich przewidywania na podstawie symptomów związanych z rozwojem pożaru oraz zgromadzonych danych sensorycznych. Artykuł ukazuje również potrzebę stworzenia systemu, który wspomagałby kierującego działaniem ratowniczym na miejscu akcji. Wprowadzenie: Nieliniowe efekty pożaru, takie jak rozgorzenie, wsteczny ciąg płomieni, czy też zapalenie lub wybuch gazów pożarowych stanowią poważne zagrożenie dla strażaków. Czynnikiem stwarzającym niebezpieczeństwo dla ratowników, będącym skutkiem gwałtownego rozwoju pożaru w obiekcie, są przede wszystkim wysoka temperatura i związane z nią promieniowanie cieplne. Na podstawie danych zgromadzonych w trakcie rozpoznania trudno jest dokładnie określić szanse wystąpienia wspomnianych zjawisk. Istnieje zatem konieczność podjęcia prac nad stworzeniem systemu, posiadającego możliwość przewidywania wystąpienia wstecznego ciągu płomieni oraz rozgorzenia, także na podstawie danych sensorycznych pochodzących z pomieszczenia objętego pożarem. Wspomniany system byłby niewątpliwie przydatnym narzędziem zwiększającym efektywność i bezpieczeństwo działań strażaków. Ponadto taki system dałby kierującemu działaniem ratowniczym większą pewność w podejmowaniu decyzji oraz pozwalałby na eliminację decyzji prowadzących do powstania rozgorzenia lub wstecznego ciągu płomieni. Metodologia: Przy opracowaniu artykułu bazowano na dwóch metodach naukowych: analizie i krytyce piśmiennictwa, stanowiącej punkt wyjściowy do analiz i źródło hipotez naukowych podlegających weryfikacji oraz uogólnionej metodzie ankietowej polegającej na konfrontacji obecnego stanu wiedzy reprezentowanego przez piśmiennictwo z wiedzą ekspercką doświadczonych dowódców PSP. Wnioski: Nieliniowe efekty pożaru, w przypadku ich wystąpienia, stanowią duże zagrożenie dla strażaków-ratowników. Stworzenie systemu analizującego na bieżąco dane sensoryczne gromadzone w miejscu prowadzonych działań pozwoliłoby na przewidywanie z wyprzedzeniem ich powstania, co wpływałoby na podniesienie bezpieczeństwa strażaków. System taki mógłby działać zarówno w oparciu o dane pochodzące z czujników, jak i z rozpoznania – strażak wprowadzałby dane do urządzenia ręcznie, co dawałoby możliwość pełnego wykorzystania jego potencjału.
EN
Aim: This article describes events, which occur during the development of a fire inside buildings. Special attention is devoted to the development of backdraft and flashover. Additionally, the article identifies possibilities for earlier prediction of potential developments based on symptoms and data from sensors. Furthermore, the article highlights a need to build a system, which supports commanders at the scene of an incident. Introduction: Extreme fire behaviour such as ventilation induced flashover, backdraft, and gas ignition or smoke explosion, pose significant threats to human life and property. A factor contributing to the significant risk for firefighters is associated with the rapid increase in the rate of heat release and temperature within structures. Based on data gathered from a reconnaissance, it is difficult to predict the probability of above mentioned events happening. Therefore, there is a need to devise a system with the potential for prediction of extreme fire behaviour, based on sensor data derived from premises engulfed by a fire. Such a system will undoubtedly be a useful tool, which will enhance the effectiveness and safety of firefighters. Furthermore, such a tool will support incident commanders in decision making and allow for the elimination of decisions, which could lead to development of flashover or backdraft. Methodology: The study utilised two scientific approaches: review and critical analysis of literature, which provided an exit point and source of verifiable scientific hypotheses. This was enhanced by survey methods based on a contrast of current knowledge identified in literature with practical know how of experienced commanders from the Polish State Fire Service. Conclusions: Non-linear progression and unpredictable fire behaviour, when it occurs, creates significant dangers to firefighters. Development of a system, which can analyse current sensor data gathered at the scene of a fire incident, will allow for the anticipation of extremes in fire progression with a consequential impact on safety. Such a system could function on the basis of data obtained from sensors as well as from information gathered during a reconnaissance - a firefighter could enter data manually, thus maximising the use of the system potential.
3
Content available remote Problematyczna wentylacja oddymiająca garaży zamkniętych - projektowanie na podstawie zasad wiedzy technicznej
Fliszkiewicz M., Krauze A., Ilnicki M., Kubera D.
Ciepłownictwo, Ogrzewnictwo, Wentylacja
|
2015
|
T. 46, nr 6
223--229
PL
Projektowanie wentylacji oddymiającej garaży zamkniętych jest zadaniem skomplikowanym dla wielu architektów, projektantów oraz rzeczoznawców ds. zabezpieczeń przeciwpożarowych. Poprawne zaprojektowanie rzeczonego urządzenia przeciwpożarowego wymaga posiadania wiedzy z zakresu wielu norm zagranicznych oraz szeroko rozumianych zasad wiedzy technicznej. Często jednak wiedza ta pozostaje w sprzeczności z obowiązującymi w Polsce przepisami przeciwpożarowymi. W niniejszym artykule autorzy odniosą się do kilku wybranych problemów występujących podczas procesu projektowego wentylacji pożarowej garaży zamkniętych.
EN
Design of smoke ventilation in closed garages is a complicated task for many architects, designers and experts in fire protection. Proper design of fire equipment requires a knowledge of many foreign standards and widely understood principles of technical knowledge. However, this knowledge is often in contradiction with the Polish fire regulations. In this article, we will refer to a few selected problems encountered during design process of fire ventilation in closed garages.
4
Content available Możliwości stosowania programów komputerowych w inżynierii bezpieczeństwa pożarowego
Fliszkiewicz M., Krauze A., Maciak T.
Bezpieczeństwo i Technika Pożarnicza
|
2013
|
Nr 1
47-60
PL
W artykule przedstawiono ogólny zarys i problematykę związaną z wykorzystaniem programów komputerowych w zakresie analizy i prognozowania wybranych zagrożeń. Dokonano przeglądu oprogramowania i jego możliwości wykorzystania w świetle polskiego prawa. Szczególną uwagę skupiono na dwupoziomowej formule przepisów, która w przyszłości umożliwiać będzie projektowanie obiektów budowlanych w oparciu o metody obliczeniowe. Opisano obszary, w których obecnie wykorzystuje się programy komputerowe w celu oszacowania bezpieczeństwa. Ponadto, autorzy omawiają podstawowe wymagania, jakie powinny spełniać programy do modelowania wybranego zagrożenia. W artykule przedstawiono możliwości programów komputerowych z zakresu modelowania rozwoju pożaru, modelowania zachowania się konstrukcji w czasie pożaru oraz modelowania skutków awarii przemysłowych. Dla każdej z wymienionych dziedzin przygotowano przegląd oprogramowania wraz ze spisem podstawowych funkcji. Zaproponowano wymagania dotyczące formy wprowadzania danych wejściowych oraz formy prezentacji danych wyjściowych. Wszystkie informacje zaprezentowano w formie tabel porównujących możliwości wybranych programów.
EN
The article describes general outline and main problems connected with using computer programs for analysis and forecasting of selected threats. An overview of the software and its possibility to apply in the light of Polish law was presented. Particular attention is focused on the two-tier formula regulations, which in the future will allow to design buildings based on computational methods. The areas in which computer programs are used to assess safety are shown. In addition, the authors discuss the basic requirements to be met by the selected software. The article discusses the possibilities of software development in the field of fire modeling, modeling behavior of the structure during the fire, and modeling the effects of industrial accidents. For each of these areas overview of the software, together with a list of basic functions was prepared. Proposed requirements for input data entry form and presentation of the output were also discussed. All information is presented in the form of tables comparing the capabilities of selected programs.
5
Content available Symulacje komputerowe jako metoda szacowania wymaganego czasu ewakuacji
Fliszkiewicz M., Krauze A., Maciak T.
Zeszyty Naukowe SGSP / Szkoła Główna Służby Pożarniczej
|
2012
|
Nr 44
111--132
PL
W artykule przedstawione zostały inżynierskie metody wyznaczania wymaganego czasu ewakuacji dla przykładowego budynku opery. W celu oszacowania czasu ewakuacji wykorzystano symulacje komputerowe oraz brytyjski standard w tym zakresie [1]. Ponadto, w pracy zamieszczono krótki przegląd aktualnie dostępnego na rynku oprogramowania.
EN
Proper management of evacuation processes is one of the basic requirements within life safety concepts. Many times it helps to prevent dangerous situations which may occur during the evacuation. The performance based on fire codes allow the use of numerical simulation of evacuation processes to improve the fire safety in buildings. Actually, there are approximately 40 programs for modeling this phenomenon, but each has some limitations, which the potential user should know. This paper describes two methods of estimating the required safe escape time: the computer simulation and the British standard. Both methods were compared and the required safe escape time was assessed. It was based on the opera house example.
6
Content available Modelowanie probabilistyczne na potrzeby szacowania ryzyka pożarowego
Fliszkiewicz M., Krauze A., Maciak T.
Zeszyty Naukowe SGSP / Szkoła Główna Służby Pożarniczej
|
2012
|
Nr 43
49--61
PL
W artykule przedstawiono ogólny zarys i problematykę związaną z wykorzystaniem narzędzia inżynierii bezpieczeństwa pożarowego jakim jest program Probabilistic Fire Simulator. Zaprezentowano zadanie projektowe, w którym przeprowadzono obliczenia wielokrotne z wykorzystaniem modelu strefowego oraz programu PFS.
EN
Building fire risk analysis is a complex subject. It is important to remember that when embarking on a building fire risk analysis effort, one should take care to identify and involve the interested and affected stakeholders, carefully consider the range of risk issues involved, and seek the most appropriate approaches, tools, methods, and data for the problem.
7
Content available Badanie skuteczności projektowanych instalacji wentylacji oddymiającej , przy wykorzy staniu symulacji CFD
Fliszkiewicz M., Krauze A., Maciak T
Zeszyty Naukowe SGSP / Szkoła Główna Służby Pożarniczej
|
2012
|
Nr 43
13--35
PL
W artykule zaprezentowano możliwości wykorzystania oprogramowania FDS, do oceny skuteczności przyjętych rozwiązań w projekcie instalacji wentylacji oddymiającej. Przedstawiono zasady projektowania systemów oddymiania oraz omówiono zaawansowaną technikę sprawdzenia efektywności działania urządzeń służących do usuwania dymu.
EN
Fire Dynamics Simulator (FDS) is a computational fluid dynamics (CFD) model of fire-driven fluid flow. The software solves numerically a form of the Navier-Stokes equations appropriate for low-speed, thermally-driven flow, with an emphasis on smoke and heat transport from fires. FDS is a powerful tool designed for particular fire hazard analysis and solving issues connected with fire safety engineering, especially to evaluate the accuracy of the solutions adopted in the project of smoke ventilation system. Its practical application supports designing non-standard buildings abide by the rules of fire safety, but mainly FDS is an advanced method of verifying the effectiveness of equipment used for smoke removal.
8
Content available Modelowanie rozwoju pożaru i rozprzestrzeniania się dymu przy wykorzystaniu numerycznej mechaniki płynów, na przykładzie oprogramowania FDS
Fliszkiewicz M., Krauze A., Maciak T.
Bezpieczeństwo i Technika Pożarnicza
|
2012
|
Nr 1
85-94
PL
Program Fire Dynamics Simulator (FDS) wykorzystuje metody obliczeniowe numerycznej mechaniki płynów CFD. Model CFD, zastosowany w programie FDS pozwala badać rozwój pożaru w złożonych geometriach. CFD opisuje ruch płynu na podstawie rozwiązań układu równań różniczkowych cząstkowych Naviera-Stokesa. Wykorzystują one zasady zachowania masy, pędu i energii. W ramach sprawdzenia możliwości praktycznego wykorzystania programów komputerowych CFD w inżynierii bezpieczeństwa pożarowego, została wykonana symulacja komputerowa rozwoju pożaru oraz rozprzestrzeniania się dymu w obiekcie handlowym, z uwzględnieniem działania mechanicznej wentylacji oddymiającej. Symulację wykonano w programie Fire Dynamics Simulator.
EN
Fire Dynamics Simulator (FDS) is a computational fluid dynamics (CFD) model of fire-driven fluid flow. The software solves numerically a form of the Navier-Stokes equations appropriate for low-speed, thermally-driven flow, with an emphasis on smoke and heat transport from fires. FDS is a powerful tool designed for particular fire hazard analysis and solving issues connected with fire safety engineering. Its practical application supports designing non-standard buildings abide by the rules of fire safety. This article describes general outline and main problems connected with using fire safety engineering tools like FDS. As a check, a practical usage of CFD computer programs in fire safety engineering, computer simulation was made of fire growth and spread of smoke in the building trade, including the operation of mechanical smoke ventilation.
9
Content available remote Numerical analysis of femur in living and dead phase
Krauze A., Kaczmarek M., Marciniak J.
Journal of Achievements in Materials and Manufacturing Engineering
|
2008
|
Vol. 26, nr 2
163-166
EN
Purpose: The paper presents numerical analysis results of stresses and displacement in femur in a living and a dead phase. The aim of the work was to present the influence of different mechanical properties of bone tissue on the obtained results. The appropriate selection of the properties ensures correct results, comparable with the results obtained in real conditions. Design/methodology/approach: The analysis was carried out on the femur of adult. The influence of the selected properties on the results of numerical analyses was analyzed. In order to carry out calculations, 3 models of diverse mechanical properties (Young modulus of bone in a living phase EI=17260 MPa, Young modulus in order to carry out a comparison analysis EII=18600 MPa and Young modulus of bone in a dead phase EIII=20202 MPa) were selected. Findings: The analyses showed the difference in displacements and reduced stresses depending on the selected mechanical properties. The analyses show that in order to select the appropriate stabilization method, mechanical characteristics of bone structures should be considered as viscoelastic. Quality of bone structures depends on individual features (genetic, hormonal, metabolic and circulatory factors). Research limitations/implications: The limitations were connected with simplification of numerical model of femur as well as with the selected boundary conditions. Practical implications: The obtained results can be useful in clinical practice. They can be applied in selection of stabilization methods or rehabilitation as well as in describing the biomechanical conditions connected with type of bone fracture obtained from medical imaging. Originality/value: Stress-displacement characteristics of femur for different degrees of demineralization, obtained from the numerical analyses were presented in the work.
10
Content available remote Corrosion behaviour of AISI 316L steel in artificial body fluids
Kajzer W., Krauze A., Marciniak J.
Journal of Achievements in Materials and Manufacturing Engineering
|
2008
|
Vol. 31, nr 2
247-253
EN
Purpose: The paper presents the comparison of corrosion resistance of AISI 316L stainless steel in variouscorrosive media such as artificial urine, Tyrode's physiological solution and artificial plasma. Design/methodology/approach: The tests were carried out on samples of the following surfaces: grinded-average roughness Ra=0.31 μ m and electropolished and chemically passivated average roughness Ra=0.10 μ m. The corrosion tests were realized by recording of anodic polarization curves with the use of the potentiodynamic method. The VoltaLab ® PGP 201 system for electrochemical tests was applied. The tests were carried out in electrolyte simulating urine (pH=6-6.4), Tyrode's physiological solution (pH=6.8-7.4) and plasma (pH=7.2-7.6) at the temperature of 37± 1° C. Findings: Surface condition of AISI 316L stainless steel determines its corrosion resistance. The highestvalues of breakdown potentials were recorded for all electropolished and chemically passivated samples in allsimulated body fluids. The highest values of anodic current density were recorded for samples tested in artificialurine, the lowest values were recorded for samples tested in Tyrode's physiological solution. Research limitations/implications: The obtained results are the basis for the optimization of physicochemical properties of the AISI 316L stainless steel. Practical implications: On the basis of the obtained results it can be stated that stainless steel meets the basic biocompatibility criteria and can be applied in reconstruction surgery, operative cardiology and urology. Originality/value: The paper presents the influence of various corrosive media simulating human body fluids on corrosion resistance of AISI 316L stainless steel.
11
Content available remote Corrosion resistance of metallic implants used in bone surgery
Kiel M., Krauze A., Marciniak J.
Archives of Materials Science and Engineering
|
2008
|
Vol. 30, nr 2
77-80
EN
Purpose: The purpose of the research was analysis of influence of mechanical damages on the implants’ surface made of Cr-Ni-Mo steel on the pitting corrosion resistance. Analysis was performed for implants after different time of implantation applied for stabilization of the funnel chest and for stabilization bone fractures, as well as for intramedullary nails in the initial state. Design/methodology/approach: Research were performed on three groups of implants after different implantation time. Research were based on the potentiodinamic tests by recording the anodic polarization curves. The tests were performed in the Tyrode’s physiological solution. Findings: The research effect was determination the corrosion potential Ecorr and breakdown potential Eb for three groups of implants after different time of implantation and different mechanical surface damages. On the basis of investigation it was stated that for all implants the breakdown potential was in the range of Eb = +549 – +1017 mV and the corrosion potential was in the range of Ecorr = -143 – +103 mV. Research limitations/implications: The obtained results can be applied to comparing the effects of possible postoperative complications. They also show the relation between the damage of surface layers and implantation time. The values of corrosion and breakdown potentials indicate good corrosion resistance of the applied austenitic stainless steel. Practical implications: The essential influence on the corrosion resistance had the time of implantation and size of surface damages. The results of research of implants made of Cr-Ni-Mo austenitic stainless steel presents that the steel was performed quality requirements for metallic biomaterials used for tested implants. Originality/value: The work presents the results of pitting corrosion tests for metallic implants made of Cr-Ni- Mo steel in the initial state and after different implantation time.
12
Content available remote Surface modification and corrosion resistance of Ni-Ti alloy used for urological stents
Kajzer W., Kaczmarek M., Krauze A., Marciniak J.
Journal of Achievements in Materials and Manufacturing Engineering
|
2007
|
Vol. 20, nr 1-2
123-126
EN
Purpose: The work presents the influence of the surface treatment of Ni-Ti alloy, intended for implants applied in urogenital surgery, on their corrosion resistance. The tests were carried out in the simulated urine at the temperature 37 plmin 1 degree centigrade and pH = 5.6-6.4. In particular, the pitting and crevice corrosion resistance tests were carried out. Design/methodology/approach: The corrosion tests were realized by recording of anodic polarization curves with the use of the potentiodynamic method. The VoltaLab(R) PGP 201 system for electrochemical tests was applied. The tests were carried out in electrolyte simulating urine (pH = 5.6-6.4) at temperature of 37 plmin 1 degree centigrade. Findings: Surface condition of metallic biomaterial determines its corrosion resistance. Research limitations/implications: The obtained results are the basis for the optimization of physicochemical properties of the Ni-Ti alloy. Practical implications: On the basis of the obtained results it can be stated that Ni-Ti alloy can be applied in urology. Originality/value: The paper presents the influence of the surface treatment on corrosion resistance of Ni-Ti alloy.
13
Content available Analiza numeryczna płyt do leczenia lejkowatej klatki piersiowej
Krauze A., Marciniak J.
Engineering of Biomaterials
|
2007
|
Vol. 10, no. 67-68
32-34
14
Content available remote Surface modification and corrosion behavior of Ni-Ti alloy used for urological implants
Kajzer W., Kaczmarek M., Krauze A., Marciniak J.
Archives of Materials Science and Engineering
|
2007
|
Vol. 28, nr 9
525-532
EN
Purpose: The work presents the influence of the surface treatment of Ni-Ti alloy, intended for implants applied in urogenital surgery, on their corrosion resistance. The tests were carried out in the simulated urine. In particular, the pitting and crevice corrosion resistance tests were carried out. Design/methodology/approach: The corrosion tests were realized by recording of anodic polarization curves with the use of the potentiodynamic method. The VoltaLab PGP 201 system for electrochemical tests was applied. The tests were carried out in electrolyte simulating urine (pH =5,6 ÷ 6,4) at the temperature of 37 ± 1°C. The tests were carried out on samples of the following surfaces: grinded-average roughness Ra=0,16 µm and electropolished and chemically passivated average roughness Ra=0,10 µm. Findings: Surface condition of Ni-Ti alloys determines its corrosion resistance. Research limitations/implications: The obtained results are the basis for the optimization of physicochemical properties of the Ni-Ti alloy. Practical implications: On the basis of the obtained results it can be stated that Ni-Ti alloy can be applied in urology. Originality/value: The paper presents the influence of the surface treatment on corrosion resistance of Ni-Ti alloy.
15
Content available remote Biomechanical analysis of plates used in treatment of pectus excavatum
Krauze A., Marciniak J., Marchacz A.
Archives of Materials Science and Engineering
|
2007
|
Vol. 28, nr 5
301-304
EN
Purpose: The paper presents computer simulation results of displacement, strain and stresses in the plate used in treatment of the pectus excavatum. Design/methodology/approach: The numerical analysis was performed for selected models of the stabilizing plates made of the Cr-Ni-Mo stainless steel (AISI 316L) and Ti-6Al-4V ELI alloy. Findings: The displacement, strain and stress analyses showed the diverse results depending on the plates geometry and the properties of the applied metallic biomaterial. The numerical analysis shows that stresses in plates didn't exceed the yield point: for the stainless steel R p0,2 min=690 MPa and Ti-6Al-4V ELI - Rp 0,2min =895 MPa. Research limitations/implications: The limitations were connected both with the necessity of simplifications applied to the numerical model and with the established boundary conditions. Practical implications: The obtained results are the basis for the stabilizing plate optimization to ensure favorable conditions for the pectus excavatum treatment. Originality/value: The work presents the displacement-strain-stress characteristics obtained on the basis of the numerical analysis.
16
Content available Influence of mechanical damage on corrosion resistance of plates used in funnel chest treatment
Krauze A., Kajzer W., Dzielicki J., Marciniak J.
Journal of Medical Informatics & Technologies
|
2006
|
Vol. 10
133--141
EN
The paper presents influence of mechanical surface damage on corrosion resistance of plates made of Cr-Ni-Mo stainless steel, used in funnel chest treatment. The surface of the steel was electrochemically polished and fitted. The surface damage is induced in the given deformation regions and is a potential reason of corrosion. The corrosion tests were realised by recording of anodic polarization curves with the use of the potentio-dynamic method. The VoltaLab® PGP 201 system for electrochemical tests was applied. Additionally, the tests showed that the structure of the steel the plates were made of, met the PN-ISO 5832-1 standard. On the basis of the obtained results it can be stated that that stainless steel can be applied in funnel chest treatment.
17
Content available remote Physicochemical properties of fixation plates used in funnel chest treatment
Krauze A., Kajzer W., Walke W., Dzielicki J.
Journal of Achievements in Materials and Manufacturing Engineering
|
2006
|
Vol. 18, nr 1-2
151--154
EN
Purpose: The paper presents physicochemical properties and biomechanical analysis of fixation plates made of Cr-Ni-Mo stainless steel used in the funnel chest treatment. Design/methodology/approach: The corrosion tests were realized by recording of anodic polarization curves with the use of the potentiodynamic method. The VoltaLab® PGP 201 system for electrochemical tests was applied. The numerical analysis was performed for: the stabilizer of 460 mm length, 16 mm width and 4.5 mm thickness, the stabilizer of 460 mm length, 16 mm width and 3.5 mm thickness, the stabilizer of 460 mm length, 16 mm width and 2.5 mm thickness. Findings: The tests showed that structure of the steel the plates were made of, met the PN-ISO 5832-1 standard. The surface damage is induced in the given deformation regions and is a potential reason of corrosion. The numerical analysis shows that stresses in plates didn’t exceed the yield point: for the stainless steel Rp0,2min = 590 MPa. Values of maximum displacements occuring in the stabilizing bar in the range of clinically acceptable displacements. Research limitations/implications: The obtained results are the basis for the optimization of physicochemical and mechanical properties of the metallic biomaterial. Practical implications: On the basis of the obtained results it can be stated that that stainless steel can be applied in the funnel chest treatment. Originality/value: The paper presents the influence of surface damage and stresses and displacement of plates used in the funnel chest treatment on the corrosion resistance.
18
Content available remote Numerical method in biomechanical analysis of intramedullary osteosynthesis in children
Krauze A., Marciniak J.
Journal of Achievements in Materials and Manufacturing Engineering
|
2006
|
Vol. 15, nr 1-2
120--126
EN
Purpose: The paper presents the biomechanical analysis of intramedullary osteosynthesis in 5-7 year old children. Design/methodology/approach: The numerical analysis was performed for two different materials (stainless steel – 316L and titanium alloy – Ti-6Al-4V) and for two different fractures of the femur (1/2 of the bone shaft, and 25 mm above). Furthermore, the stresses between the bone fragments were calculated while loading the femur with forces derived from the trunk mass. In the research the Metaizeau method was applied. This method ensures appropriate fixation without complications. Findings: The numerical analysis shows that stresses in both the steel and the titanium alloy nails didn’t exceed the yield point: for the stainless steel Rp0,2,min= 690 MPa and for the titanium alloy Rp0,2,min = 895 MPa. Research limitations/implications: The obtained results are the basis for the optimization of mechanical properties of the metallic biomaterial. Practical implications: On the basis of the obtained results it can be stated that both stainless steel and titanium alloy nails can be aplied in elastic osteosythesis in femur fractures in children. Originality/value: The obtain results can be used by physicians to ensure elastic osteosythesis that accelerate bone union.
19
Content available remote Corrosion resistance of Cr-Ni-Mo steel in simulated body fluids
Kajzer W., Krauze A., Walke W., Marciniak J.
Journal of Achievements in Materials and Manufacturing Engineering
|
2006
|
Vol. 18, nr 1-2
115--118
EN
Purpose: The paper presents the comparison of corrosion resistance of Cr-Ni-Mo stainless steel in various corrosive media simulating human body fluids. Design/methodology/approach: The corrosion tests were realized by recording of anodic polarization curves with the use of the potentiodynamic method. The VoltaLab® PGP 201 system for electrochemical tests was applied. The tests were carried out in electrolyte simulating urine (pH = 6 ÷ 6.4), Tyrode’s physiological solution (pH = 6.8 ÷ 7.4) and plasma (pH = 7.2 ÷ 7.6) at the temperature of 37±1°C. Findings: Surface condition of metallic biomaterial determines its corrosion resistance. The highest values of breakdown potentials are recorded for electropolished and chemically passivated samples tested in artificial urine. The lowest values of anodic current density were recorded for samples tested in Tyrode’s physiological solution. Research limitations/implications: The obtained results are the basis for the optimization of physicochemical properties of the metallic biomaterial. Practical implications: On the basis of the obtained results it can be stated that stainless steel can be applied in reconstruction surgery, operative cardiology and urology. Originality/value: The paper presents the influence of various corrosive media simulating human body fluids on corrosion resistance of Cr-Ni-Mo stainless steel.
20
Content available Odporność korozyjna płyt stosowanych w leczeniu lejkowatej klatki piersiowej
Krauze A., Marciniak J., Dzielicki J.
Inżynieria Biomateriałów
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2006
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R. 9, nr 58-60
149-152
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