Full-text resources of CEJSH and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl

Results found: 3

first rewind previous Page / 1 next fast forward last

Search results

Search:
in the keywords:  tensile strength
help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Publication available in full text mode
Content available

An in vitro study for the evaluation of morphological and biochemical characteristics of absorbable sutures coated with genistein and nicotine

100%
Chopra A., Cecil A., Eshwaramoorthy R., John R. S.
European Journal of Clinical and Experimental Medicine
|
2023
|
issue 4
742-749
EN
Introduction and aim. Inflammation, cell proliferation, matrix deposition, and tissue remodeling are all elements of the well-structured and well-coordinated process of wound repair. The aim of this study was to analyze the effect of genistein and nicotine on polyglycolic acid (PGA) and vicryl sutures. Material and methods. Genistein and nicotine were isolated and solution was prepared and the suture material PGA and vicryl were immersed in the solution and dried. They were tested for their tensile strength and degradation values after immersion in artificial saliva (on the first day and on the 14th day). The sutures were also seen under a scanning electron microscope (SEM) for its uniform coating and the mixture formulation of genistein and nicotine were tested for their anti-inflammatory and antioxidant activity using protein denaturation assay and 2,2-diphenyl-1-picrylhydrazyl assay respectively. Results. Nicotine has a high anti-inflammatory activity on the suture material, whereas Genistein has an insignificant anti-inflammatory effect. The mixture formulation has a relatively similar anti-inflammatory effect when compared to the control. The SEM analysis shows a uniform coating of the formulation on the PGA and vicryl sutures. In comparison, PGA has shown lesser tensile strength and hence higher degradation ability. Conclusion. Nicotine and Genistein affect the tensile strength and degradation properties of the sutures.
2

Mechanical Properties of Lining Leathers Finished with the Addition of Oregano Essential Oil

84%
Bielak E., Marcinkowska E.
Zeszyty Naukowe Uniwersytetu Ekonomicznego w Krakowie
|
2017
|
issue 7(967)
19-31
EN
The hygienic properties of lining leathers can be improved significantly by introducing oregano essential oil into leathers. This is because adding antiseptic oil makes leathers more resistant to microorganisms that are potentially harmful to humans and cause damage to animal leathers. The paper presents the results of tests to check selected mechanical properties – tensile strength, elongation and tear load – of leathers fatliquored with oregano essential oil at a concentration of 3% w/w and without this treatment. The tests were carried out on the Instron 5544 testing machine. The leathers enriched with oil met the standard requirements set for lining leathers for of the parameters: tensile strength and elongation. Statistical analysis using the chi-squared, Hartley and Fisher-Snedecor tests at an assumed significance level of α = 0.05 revealed that leather enriched with oregano essential oil has a significantly higher tensile strength than leather fatliquored without this oil, while both leather samples showed no significant difference in elongation and tear load. Thus, it can be concluded that adding 3% w/w of oil will have not have an adverse effect on basic mechanical properties of leathers.
PL
Higieniczność skór podszewkowych można znacząco poprawić dzięki wprowadzeniu do skóry olejku lebiodkowego, ponieważ dodatek olejku o działaniu antyseptycznym pozwala na nadanie skórze oporności wobec mikroorganizmów potencjalnie szkodliwych dla człowieka oraz powodujących destrukcję skór zwierzęcych. W artykule przedstawiono wyniki badań wybranych właściwości mechanicznych skór natłuszczonych z dodatkiem oraz bez dodatku olejku lebiodkowego w stężeniu 3% na masę skóry, tj. wytrzymałości na rozciąganie, wydłużenia i siły rozdzierającej, które wykonano na maszynie wytrzymałościowej Instron 5544. Skóry uszlachetnione olejkiem spełniały wymagania podane w normie wyrobu stawiane skórom podszewkowym w zakresie wytrzymałości na rozciąganie oraz wydłużenia. Analiza statystyczna z wykorzystaniem testów chi-kwadrat, Hartleya oraz Fishera-Snedecora przy przyjętym poziomie istotności α = 0,05 wykazała, że w przypadku badanych próbek wytrzymałość na rozciąganie skóry z dodatkiem olejku lebiodkowego była istotnie wyższa od wartości tego parametru w skórze natłuszczonej bez dodatku olejku, zaś wydłużenie oraz siła rozdzierająca skóry z dodatkiem olejku nie różniły się istotnie od wydłużenia i siły rozdzierającej skóry bez dodatku substancji naturalnej. Można zatem stwierdzić, że dodatek olejku w ilości 3% na masę skóry nie będzie miał niekorzystnego wpływu na podstawowe właściwości mechaniczne skór uszlachetnionych tym olejkiem.
3
Publication available in full text mode
Content available

Analysis of the impact of high temperature on the change in tensile strength of cement mortars with or without polypropylene fibres added

84%
Drzymala T., Reszka M.
Scientific Journal of the Military University of Land Forces
|
2018
|
vol. 50
|
issue 3(189)
109-126
EN
When evaluating concrete, its strength is the most important feature from the practical point of view. In compliance with technological requirements, the strength of concrete depends primarily on its composition, mainly on the content and strength of cement slurry. This is because this concrete component is most susceptible to changes in working conditions in a construction, including high temperature impact on concrete during the fire. The paper presents the results of tests performed on the cement mortar with and without the addition of polypropylene fibers. This treatment allowed for the elimination of the effect of the coarse aggregate by reason of the accuracy of the tested strength characteristics. The studies concerned the impact of high temperature on the change in tensile strength of cement mortars modified with the addition of polypropylene fibers. The analysis of available literature shows that one of the main causes of concrete’s thermal spalling is seen in high tensile stresses. The results of many tests prove that the addition of polypropylene fibers can have a positive effect on the behavior of concrete structures at high temperatures and help reduce spalling. The polypropylene fibers present in a composite may also positively influence the increase in tensile strength. This article discusses the purpose and scope of research, research methods, the experiment plan, test benches, and test results as well. The conclusions of the study were formulated in the final part of the article.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.