Laser Annealing on the Surface Treatment of Thin Super Elastic NiTi Wire

Here the aim of this research is annealing the surface of NiTi wire for shape memory alloy, super-elastic wire by solid state laser beam. The laser surface treatment was carried out on the NiTi wire locally with fast, selective, surface heat treatment that enables precisely tune the localized material properties without any precipitation. Both as drawn (hard) and straight annealing NiTi wire were considered for laser annealing with input power 3 W, with precisely focusing the laser beam height 14.3 % of the Z-axis with a spot size of 1 mm. However, straight annealing wire is more interest due to its low temperature shape setting behavior and used by companies for stent materials. The variable parameter such as speed of the laser scanning and tensile stress on the NiTi wire were optimized to observe the effect of laser response on the sample. Superelastic, straight annealed NiTi wires (d: 0.10 mm) were held prestrained at the end of the superelastic plateau (epsilon: 5 similar to 6.5 %) above the superelastic region by a tensile machine (Mitter: miniature testing rig) at room temperature (RT). Simultaneously, the hardness of the wires along the cross-section was performed by nano-indentation (NI) method. The hardness of the NiTi wire corresponds to phase changes were correlated with NI test. The laser induced NiTi wire shows better fatigue performance with improved 6500 cycles

Probabilistic-deterministic transition involved in a fragmentation process of brittle materials: Application to a high performance concrete

International audienceDynamic loadings produce high stress waves leading to the fragmentation of brittle materials such as ceramics, concrete, glass and rocks. The transition from single fragmentation (under quasi static loading condition) to multiple fragmentation (dynamic loading) is discussed and a damage model based upon the fragmentation analysis is applied to analyze edge-on-impact of a high performnace concrete

Design of a Robotic Manipulator for Loading of Strip Detector Staves

V této práci se věnuji konstrukčnímu návrhu manipulátoru pro zakládání modulů stripového detektoru do jeho konstrukce za použití technologie 3D tisku. Manipulátor s virtuální osou rotace bude zakládat moduly do čtyř soustředných vrstev. Moduly budou v jednotlivých vrstvách naklopeny vzhledem k ose rotace detektoru (nutnost užití virtuální osy rotace). Manipulátor musí tedy umožnit rotační pohyb po kružnici v plném rozsahu, pohyb v radiálním směru pro změnu vrstev a naklopení modulu. Dále pak řešení problematiky nastavení tisku dílů pro dosažení nejlepších výsledků z hlediska životnosti, zachování tuhosti a snížení hmotnosti.In this work I design the manipulator to load the strip detector modules into its structure using 3D printing technology. The manipulator with virtual axis of rotation loads modules into four concentric layers. The modules are tilted in individual layers with respect to the axis of the detector rotation (need for the virtual axis of rotation). The manipulator must therefore allow rotational movement in a circle in the full range, movement in the radial direction to change the layers and tilting the module. Finding correct settings for 3D printing to achieve best results in terms of durability, toughness and mass reduction

Investigation of magneto-structural phase transition in FeRh by reflectivity and transmittance measurements in visible and near-infrared spectral region

Magneto-structural phase transition in FeRh epitaxial layers was studied optically. It is shown that the transition between the low-temperature antiferromagnetic phase and the high-temperature ferromagnetic phase is accompanied by a rather large change of the optical response in the visible and near-infrared spectral ranges. This change is consistent with ab initio calculations of reflectivity and transmittance. Phase transition temperatures in a series of FeRh films with thicknesses ranging from 6 to 100 nm is measured thereby demonstrating the utility of the method to quickly characterise samples. Spatially resolved imaging of their magnetic properties with a micrometer resolution shows that the phase transition occurs at different temperatures in different parts of the sample

Content of specialized metabolites and antimicrobical activitey of spices extracts

Začini i općenito aromatično bilje, izvor su različitih specijaliziranih metabolita, bioaktivnih komponenata, posebice polifenolnih spojeva koji pokazuju značajno antioksidacijsko i antimikrobno djelovanje. Izolacija navedenih spojeva iz aromatičnog bilja predstavlja velik izazov, ponajprije zbog postupaka koji često mogu uzrokovati i njihovu degradaciju. Stoga se danas sve više primjenjuju neinvazivne metode poput ultrazvukom potpomognute ekstrakcije koja omogućuje izolaciju relativno velike mase uzorka u kratkom vremenu. Cilj ovog rada bio je utvrditi fizikalno-kemijska svojstva i sadržaj specijaliziranih metabolita u ekstraktima začina praha češnjaka, kurkume i đumbira uspoređujući klasičnu i ultrazvučnu ekstrakciju pri tri različite temperature (21,7, 40 i 70 °C). Također, utvrditi antimikrobnu aktivnost navedenih ekstrakata prateći sposobnost preživljavanja patogenih sojeva Salmonella, Listeria monocytogenes i Staphylococcus aureus. Istraživanjem su određeni sljedeći fizikalno-kemijski parametri: gustoća otopine, elektroprovodljivost otopine, topljiva suha tvar (TST), ukupne kiseline, pH vrijednost, boja; specijalizirani metaboliti: sadržaj vitamina C, ukupnih fenola (flavonoida i neflavonoida), ukupnih karotenoida te antioksidacijski kapacitet i antimikrobna aktivnost ekstrakata začina. Prema dobivenim rezultatima može se zaključiti da su ekstrakti češnjaka, đumbira i kurkume bogati sadržajem specijaliziranih metabolita, posebice fenolnim spojevima te visokog antioksidacijskog kapaciteta. Način ekstrakcije i upotreba viših temperatura utjecali su na parametre osnovnog fizikalno-kemijskog sastava i sadržaja specijaliziranih metabolita prilikom čega je primjena ultrazvučnog tretmana (35 kHz i 140 W) i viših temperatura (40 i 70 °C) u vremenskom razdoblju od 30 minuta dovela je do povećanja sadržaja topljive suhe tvari, fenolnih spojeva (ukupnih fenola, flavonoida, neflavonoida) i karotenoida u analiziranim uzorcima. S druge strane, ultrazvuk je pozitivno utjecao na sadržaj vitamina C u uzorcima, ali se pri višim temperaturama sadržaj istog reducirao. Dodana koncentracija ekstrakata đumbira i kurkume nije pokazala značajan antimikrobni učinak na odabrane patogene sojeve, dok je ekstrakt češnjaka pokazao potencijalni antimikrobni utjecaj na rast i brojnost formiranih kolonija bakterije L. monocytogenes.Spices and generally aromatic herbs are the source of various specialized metabolites, bioactive components, especially polyphenolic compounds, which have significant antioxidant and antimicrobial activity. The isolation of these compounds from plant material is a great challenge, primarily because of processes that can often cause their degradation. Therefore, non-invasive methods such as ultrasound assisted extraction, which enables the isolation of a relatively large sample mass in a short time, are increasingly being used today. The aim of this study was to determine the physico-chemical properties and content of specialized metabolites in garlic, turmeric and ginger spice extracts by comparing classical and ultrasonic extraction at three different temperatures (21.7 , 40 and 70 °C). Also, to determine the antimicrobial activity of these extracts by following the viability of pathogenic strains of Salmonella, Listeria monocytogenes and Staphylococcus aureus. The study determined the following physico-chemical parameters: solution density, solution conductivity, total soluble solids (TST), total acids, pH value, color; specialized metabolites: vitamin C content, total phenols (flavonoids and neflavonoids) content, total carotenoids, antioxidant capacity and antimicrobial activity of spice extracts. According to the obtained results, it can be concluded that garlic, ginger and turmeric extracts are rich in specialized metabolites, especially phenolic compounds and also exhibit a high antioxidant capacity. The extraction method and the use of higher temperatures influenced on the parameters of the basic physico-chemical composition and content of specialized spice metabolites whereby the application of ultrasonic treatment (35 kHz and 140 W) and higher temperatures (40 and 70 °C) in time interval of 30 minute had increased the content of TST, phenolic compounds (total phenols, flavonoids, neflavonoids) and carotenoids in the analyzed samples. On the other hand, ultrasound had a positive effect on the vitamin C content of the samples, but at higher temperatures the content significantly decreased. The added concentration of ginger and turmeric extracts did not show a significant antimicrobial effect on selected pathogenic strains, while garlic extract showed a potential antimicrobial effect on the growth and abundance of L. monocytogenes colonies formed

Content of specialized metabolites and antimicrobical activitey of spices extracts

Začini i općenito aromatično bilje, izvor su različitih specijaliziranih metabolita, bioaktivnih komponenata, posebice polifenolnih spojeva koji pokazuju značajno antioksidacijsko i antimikrobno djelovanje. Izolacija navedenih spojeva iz aromatičnog bilja predstavlja velik izazov, ponajprije zbog postupaka koji često mogu uzrokovati i njihovu degradaciju. Stoga se danas sve više primjenjuju neinvazivne metode poput ultrazvukom potpomognute ekstrakcije koja omogućuje izolaciju relativno velike mase uzorka u kratkom vremenu. Cilj ovog rada bio je utvrditi fizikalno-kemijska svojstva i sadržaj specijaliziranih metabolita u ekstraktima začina praha češnjaka, kurkume i đumbira uspoređujući klasičnu i ultrazvučnu ekstrakciju pri tri različite temperature (21,7, 40 i 70 °C). Također, utvrditi antimikrobnu aktivnost navedenih ekstrakata prateći sposobnost preživljavanja patogenih sojeva Salmonella, Listeria monocytogenes i Staphylococcus aureus. Istraživanjem su određeni sljedeći fizikalno-kemijski parametri: gustoća otopine, elektroprovodljivost otopine, topljiva suha tvar (TST), ukupne kiseline, pH vrijednost, boja; specijalizirani metaboliti: sadržaj vitamina C, ukupnih fenola (flavonoida i neflavonoida), ukupnih karotenoida te antioksidacijski kapacitet i antimikrobna aktivnost ekstrakata začina. Prema dobivenim rezultatima može se zaključiti da su ekstrakti češnjaka, đumbira i kurkume bogati sadržajem specijaliziranih metabolita, posebice fenolnim spojevima te visokog antioksidacijskog kapaciteta. Način ekstrakcije i upotreba viših temperatura utjecali su na parametre osnovnog fizikalno-kemijskog sastava i sadržaja specijaliziranih metabolita prilikom čega je primjena ultrazvučnog tretmana (35 kHz i 140 W) i viših temperatura (40 i 70 °C) u vremenskom razdoblju od 30 minuta dovela je do povećanja sadržaja topljive suhe tvari, fenolnih spojeva (ukupnih fenola, flavonoida, neflavonoida) i karotenoida u analiziranim uzorcima. S druge strane, ultrazvuk je pozitivno utjecao na sadržaj vitamina C u uzorcima, ali se pri višim temperaturama sadržaj istog reducirao. Dodana koncentracija ekstrakata đumbira i kurkume nije pokazala značajan antimikrobni učinak na odabrane patogene sojeve, dok je ekstrakt češnjaka pokazao potencijalni antimikrobni utjecaj na rast i brojnost formiranih kolonija bakterije L. monocytogenes.Spices and generally aromatic herbs are the source of various specialized metabolites, bioactive components, especially polyphenolic compounds, which have significant antioxidant and antimicrobial activity. The isolation of these compounds from plant material is a great challenge, primarily because of processes that can often cause their degradation. Therefore, non-invasive methods such as ultrasound assisted extraction, which enables the isolation of a relatively large sample mass in a short time, are increasingly being used today. The aim of this study was to determine the physico-chemical properties and content of specialized metabolites in garlic, turmeric and ginger spice extracts by comparing classical and ultrasonic extraction at three different temperatures (21.7 , 40 and 70 °C). Also, to determine the antimicrobial activity of these extracts by following the viability of pathogenic strains of Salmonella, Listeria monocytogenes and Staphylococcus aureus. The study determined the following physico-chemical parameters: solution density, solution conductivity, total soluble solids (TST), total acids, pH value, color; specialized metabolites: vitamin C content, total phenols (flavonoids and neflavonoids) content, total carotenoids, antioxidant capacity and antimicrobial activity of spice extracts. According to the obtained results, it can be concluded that garlic, ginger and turmeric extracts are rich in specialized metabolites, especially phenolic compounds and also exhibit a high antioxidant capacity. The extraction method and the use of higher temperatures influenced on the parameters of the basic physico-chemical composition and content of specialized spice metabolites whereby the application of ultrasonic treatment (35 kHz and 140 W) and higher temperatures (40 and 70 °C) in time interval of 30 minute had increased the content of TST, phenolic compounds (total phenols, flavonoids, neflavonoids) and carotenoids in the analyzed samples. On the other hand, ultrasound had a positive effect on the vitamin C content of the samples, but at higher temperatures the content significantly decreased. The added concentration of ginger and turmeric extracts did not show a significant antimicrobial effect on selected pathogenic strains, while garlic extract showed a potential antimicrobial effect on the growth and abundance of L. monocytogenes colonies formed

MILLING TOOL DEFORMATION CAUSED BY HEATING DURING THE CUTTING PROCESS

The presented paper describes an experiment dealing with the deformation of a milling tool caused by heating during the cutting process. Based on the literature review an experimental procedure is designed to simulate heating of the milling tool during machining. The experimental heating of the milling tool is realized using a laser beam. The frequency of laser radiation and the length of each pulse are selected in order to simulate the real cutting process. The output power of the laser radiation is 10W or 20W. During the experiment deformation and temperature of the tool are measured. In the second part of the presented article an experiment is carried out investigating the heating and deformation of the milling tool during real machining of an aluminium alloy. The experiment consists of several test cycles, when a different amount of material is removed. Deformations of the tool and also of the machine tool are measured immediately after milling, and during cooling to ambient temperature. The results clearly show that there is a significant temperature rise of the milling tool during the cutting process, which mainly causes milling tool extension in the axial direction. The conclusion of the experiment is that the thermal deformation of the milling tool during machining cannot be neglected, as it can also be a source of certain errors

Robotic arm human-machine interface for laser shock peening applications

The HiLASE Centre is equipped with a Laser Shock Peening station (LSP). LSP is a surface enhancing technique and it is used to prolong the fatigue life of metallic components. Part of the station is a FANUC M-20iA/20M 6-axis industrial robotic arm equipped with an R-30iB controller. The robotic arm is used to handle the LSP samples In order to facilitate the utilisation of the LSP station at the HiLASE centre for untrained operators, a human-machine interface (HMI) for the station's industrial robotic arm is being developed. This project aims to determine what type of HMI is the most suitable for the given application and to implement this solution

NON-PROFIT ORGANIZATIONS IN THE CONTEXT OF DIGITAL TRANSFORMATION: RESEARCH RESULTS FROM POLAND

The article discusses the issue of digital transformation of non-profit organizations (NPOs). Despite increasing interest in digital transformation within the non-profit sector, few organizations actively pursue initiatives in this area. The purpose of this article is to examine 1) the level of digital advancement of non-profit organizations compared to for-profit organizations in Poland, and 2) the mediating role of digital and technical advancement in the relation between digital skills of employees and organizational performance in a non-profit organization. To achieve this objective, quantitative research was carried out in the last quarter of 2023 among non-profit organizations in Poland. The CAWI method was used, and NPOs were selected using purposive sampling. The calculations were made using the PS Imago Pro 9.0 and Process macro for SPSS ver. 4.2. The results showed that the level of digital maturity remains lower in non-profit organizations, the effect size is weak, suggesting that this difference may disappear in the future. Moreover, it was found that employees’ digital skills positively affect the organizational performance of non-profit organizations, with digital and technical advancement mediating this relationship. Of the two mediators, digital advancement plays a more significant role.Artykuł porusza problematykę transformacji cyfrowej organizacji non-profit (NPO). Mimo zwiększonego zainteresowania transformacją cyfrową ze strony organizacji non-profit wskazuje się, że niewiele z nich podejmuje jakiekolwiek działania w tym obszarze. W tym kontekście celem artykułu jest: 1) zbadanie poziomu zaawansowania cyfrowego organizacji non-profit w porównaniu do organizacji nastawionych na zysk w Polsce oraz 2) weryfikacja, czy zaawansowanie cyfrowe i techniczne (na tle konkurencji) są mediatorami relacji między umiejętnościami pracowników w zakresie posługiwania się technologiami cyfrowymi i rezultatami osiąganymi przez organizacje non-profit. Dla osiągnięcia celu pracy przeprowadzono badania ilościowe w organizacjach non-profit zlokalizowanych na terenie Polski. Badania przeprowadzono w drugim kwartale 2023 r. wykorzystując metodę CAWI. Obliczenia wykonano przy użyciu programu PS Imago Pro 9.0 oraz makra Process dla SPSS ver. 4.2. Uzyskane wyniki pokazały, że poziom dojrzałości cyfrowej w organizacjach non-profit jest w dalszym ciągu niższy w porównaniu do organizacji nastawionych na zysk, jednak różnica jest niewielka i można oczekiwać, że w przyszłości zaniknie. Co więcej, udowodniono, że umiejętności cyfrowe pracowników wpływają na rezultaty uzyskiwane przez organizacje non-profit, a zaawansowanie cyfrowe organizacji i techniczne (na tle konkurencji) pośredniczą w tej relacji. Spośród dwóch mediatorów ważniejsze jest zaawansowanie cyfrowe organizacji