Repozytorium UKWRepozytorium cyfrowe DSpace zapisuje, przechowuje, indeksuje i udostępnia cyfrowe materiały.https://repozytorium.ukw.edu.pl:4432024-03-19T06:39:19Z2024-03-19T06:39:19ZEffect of Low-Temperature Oxygen Plasma Treatment of Titanium Alloy Surface on Tannic Acid Coating DepositionWiniecki, MariuszStepczyńska, MagdalenaMoraczewski, KrzysztofSkowroński, ŁukaszTrzciński, MarekRerek, TomaszMalinowski, Rafałhttps://repozytorium.ukw.edu.pl///handle/item/81482024-02-27T10:24:04Z2024-01-01T00:00:00ZEffect of Low-Temperature Oxygen Plasma Treatment of Titanium Alloy Surface on Tannic Acid Coating Deposition
Winiecki, Mariusz; Stepczyńska, Magdalena; Moraczewski, Krzysztof; Skowroński, Łukasz; Trzciński, Marek; Rerek, Tomasz; Malinowski, Rafał
In this study, the effect of low-temperature oxygen plasma treatment with various powers of a titanium alloy surface on the structural and morphological properties of a substrate and the deposition of a tannic acid coating was investigated. The surface characteristics of the titanium alloy were evaluated by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), atomic force microscopy (AFM), and contact angle measurements. Following this, the tannic acid coatings were deposited on the titanium alloy substrates and the structural and morphological properties of the tannic acid coatings deposited were subject to characterization by XPS, SEM, and spectroscopic ellipsometry (SE) measurements. The results show that the low-temperature oxygen plasma treatment of titanium alloys leads to the formation of titanium dioxides that contain –OH groups on the surface being accompanied by a reduction in carbon, which imparts hydrophilicity to the titanium substrate, and the effect increases with the applied plasma power. The performed titanium alloy substrate modification translates into the quality of the deposited tannic acid coating standing out by higher uniformity of the coating, lower number of defects indicating delamination or incomplete bonding of the coating with the substrate, lower number of cracks, thinner cracks, and higher thickness of the tannic acid coatings compared to the non-treated titanium alloy substrate. A similar effect is observed as the applied plasma power increases.
2024-01-01T00:00:00ZHow Are Different Perfectionism Traits Related to Mental Health in Students?Larionow, Pawełhttps://repozytorium.ukw.edu.pl///handle/item/81472024-02-27T10:24:30Z2024-01-01T00:00:00ZHow Are Different Perfectionism Traits Related to Mental Health in Students?
Larionow, Paweł
Multidimensional models of perfectionism postulate the existence of various perfectionism traits, with different effects on mental health. In order to suggest parsimonious targets in psychological interventions for university students, this study aimed to explore whether, how, and which individual perfectionism traits are uniquely associated with stress and well-being. The participants were 253 students aged 18–30 who completed the Frost Multidimensional Perfectionism Scale, the Perceived Stress Scale, and the Warwick–Edinburgh Mental Well-being Scale. Controlling for the common variance of perfectionism traits in statistical analysis, it was shown that (1) Personal Standards were associated with higher well-being and lower stress, (2) Concern over Mistakes and Doubts about Actions were related to lower well-being and higher stress, (3) Parental Expectations and Parental Criticism were not correlated with stress, and (4) Parental Criticism was associated with lower well-being. In the multi-predictor mediation model, with five perfectionism traits as predictors, perceived stress was a significant mediator between several perfectionism traits (i.e., Personal Standards, Concern over Mistakes, and Doubts about Actions) and well-being. Overall, Personal Standards, Concern over Mistakes, and Doubts about Actions seem to be parsimonious psychological targets, with Personal Standards expressing mental health-promoting effects, whereas Parental Expectations and Parental Criticism seem to be less important psychological targets.
2024-01-01T00:00:00ZColor converters for white LEDs using liquid phase epitaxy growth methodMarkovskyi, AntonGorbenko, VitaliyZorenko, TetianaFedorov, A.Zorenko, Yuriyhttps://repozytorium.ukw.edu.pl///handle/item/81462024-02-26T09:30:23Z2024-01-01T00:00:00ZColor converters for white LEDs using liquid phase epitaxy growth method
Markovskyi, Anton; Gorbenko, Vitaliy; Zorenko, Tetiana; Fedorov, A.; Zorenko, Yuriy
The development of innovative high-power lighting sources is urgently required to design and investigate the new high structural quality and high-temperature stable converters in the form of single crystals and single crystalline films. This research deals with the growth and investigation of structural, luminescence, and photoconversion properties (color coordinates, color temperature and color rendering index) of the single crystalline films of Ce3+ doped (Lu, Y, Tb, Gd)3Al5O12 garnets, grown using the Liquid Phase Epitaxy method onto undoped Y3Al5O12 substrates. The combination of Ce3+ doped Lu3Al5O12, Y3Al5O12, Tb3Al5O12, Gd2.9Lu0.1Al5O12 film converter with respective thickness with commercial blue LED allows for obtaining green-yellow-orange-emitting pc-WLEDs. The application of the mentioned film converters results in the formation of four basic trends on the color diagram depending on the thickness of the converter.
2024-01-01T00:00:00ZLuminescence and photoconversion properties of Ce-doped Ca3Sc2Si3O12 crystalShakhno, AnnaGieszczyk, W.Bilski, P.Witkiewicz-Łukaszek, SandraZorenko, TetianaCieszko, MieczysławSzczepański, ZbigniewKotlov, A.Zorenko, Yuriyhttps://repozytorium.ukw.edu.pl///handle/item/81452024-02-26T09:32:20Z2024-01-01T00:00:00ZLuminescence and photoconversion properties of Ce-doped Ca3Sc2Si3O12 crystal
Shakhno, Anna; Gieszczyk, W.; Bilski, P.; Witkiewicz-Łukaszek, Sandra; Zorenko, Tetiana; Cieszko, Mieczysław; Szczepański, Zbigniew; Kotlov, A.; Zorenko, Yuriy
This work is dedicated to investigation of the luminescent properties of the prospective photoconversion material based on the crystal of Ce3+ doped Ca3Sc2Si3O12 (CSSG) garnet. The GSSG:Ce crystal was grown using the micro-pulling-down (μPD) method. The CSSG:Ce crystal exhibited an intensive photoluminescence (PL) emission band with two sub-bands peaked at 504 and 545 nm, corresponding to 5d-4f (2F5/2;7/2) transitions. Furthermore, we have investigated also the formation of cerium multicenters in the GSSG:Ce crystal using analyses of the structure of Ce3+ photoluminescence emission and excitation spectra under excitation of the luminescence of this crystal by synchrotron radiation. The formation of Ce3+-multicenters in CSSG:Ce garnet is caused by the local inhomogeneity of the dodecahedral sites of garnet lattice due to localization of the hetero-valent Sc3+ and Si4+ cations in the octahedral and tetrahedral positions of the garnet host. The existence of Ce3+ multicenters resulted in a significant enhancement of the Ce3+ emission band in the red range and improving the performance of conventional YAG:Ce phosphor. The next task of our work was to evaluate the possibility of application of the GSSG:Ce crystal as a light phosphor-converter (pc) for white light-emitting diodes (WLEDs). In the frame of this task, we have successfully developed a prototype of WLED by employing the CSSG:Ce crystal as a phosphor-converter (pc) with blue 450 emitting LED as well as investigated the color characteristics of this pc-WLED.
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