2024 - Repozytorium publikacji - Politechnika Gdańska

Pokaż publikacje z roku

Publikacje z roku 2024

Pokaż wszystkie

Soft Tissue Retraction Maneuver in Cone Beam Computed Tomography Prior to Crown-Lengthening Procedure—A Technical Note
- Paulina Adamska
- Marcin Stasiak
- Wojciech Dąbrowski
- Dorota Pylińska-Dąbrowska
- Łukasz Adamski
- Adam Zedler
- Ewa Kozłowska
- Michal Studniarek
2024 Pełny tekst Journal of Clinical Medicine
Background: An accurate determination of the biological width and the relationship of the cemento-enamel junction with the border of the alveolar bone is crucial during a clinical crown-lengthening (CCL) procedure. The aim of this study was to present a technical note about the retraction techniques in cone beam computed tomography (CBCT) prior to CCL, highlighting the significant enhancement in procedural accuracy and predictability that these techniques offer. Methods: Clinical and radiological examinations should be performed before a CCL procedure. It is necessary to determine the length of the tooth crowns, the periodontal pockets’ depth, and the phenotype of the gingiva. The ideal CBCT examination should be performed with soft tissue retraction. This can be achieved using retractors or cotton rolls. Results: Retraction of the lips, cheeks, and tongue allows one to assess the marginal gingiva, the cemento-enamel junction, and the alveolar bone. A detailed plan of the CCL procedure, which involves retraction, ensures both the aesthetic appeal and the achievement of a newly defined gingival zenith, enhancing the overall visual harmony. Conclusions: Compared with conventional radiographic imaging, the soft tissue retraction maneuver in CBCT prior to CCL surgery offers an effective approach to the evaluation and diagnosis of soft and hard tissue. This is because of the detailed planning of the aesthetic CCL procedure. Such an approach leads to superior aesthetic outcomes in dentistry, contributing to the advancement of aesthetic dentistry through a harmonious blend of art and science.
Solid and liquid fractionation of sugarcane and Agave bagasse during ozonolysis and enzymatic hydrolysis: Impact on biohydrogen and biogas production
- Jacobo Pérez-Barragán
- Octavio García-Depraect
- Rafael Maya-Yescas
- Ramiro Vallejo-Rodríguez
- Hasbleidy Palacios-Hinestroza
- Mónica Coca
- Roberto Castro Munoz
- Elizabeth León-Becerril
2024 INDUSTRIAL CROPS AND PRODUCTS
Sustainable and cost-efficient lignocellulosic biomass-to-energy bioprocesses require assessing the main components released during biomass fractionation. This study assessed the mesophilic biochemical potential of biohydrogen (BHP) and methane production (BMP) from sugarcane bagasse (SCB) and cooked (CAB) and uncooked (UAB) Agave bagasse. A systematic comparative analysis was performed for the liquid and solid fractions derived from classical enzymatic hydrolysis and ozonolysis-assisted enzymatic hydrolysis. Ozonolysis partially delignified the materials tested while preserving most fermentable sugars and avoiding the generation of inhibitors. During hydrolysis, ozonolysis also led to higher sugar yields and organic matter solubilization regardless of the bagasse type. Hydrolysates with ozonated material showed the highest BHP of 135, 94 and 105 NmL-H2/g-VSfed and BMP of 250, 269 and 247 NmL-CH4/g-VSfed, for SCB, CAB, and UAB, respectively. The total amount of energy harvested was dependent on the material tested and the biomass conversion process applied. Compared with raw material, ozonolysis, followed by enzymatic hydrolysis, increased both the BHP and BMP by 153–371% and 5–53%, respectively.
Solubility enhancement of metronidazole using natural deep eutectic solvents: Physicochemical and thermodynamic studies
- Adrian Szewczyk
- Dorota Warmińska
- Jakub Ruszkowski
- Michał Szymankiewicz
- Magdalena Prokopowicz
2024 JOURNAL OF MOLECULAR LIQUIDS
This research aimed to explore the utility of natural deep eutectic solvents (NADES) as the co-solvents for slightly water-soluble metronidazole (MNZ). After testing 70 wt% (percentage by weight) aqueous mixtures of seven NADESs, it was found that MNZ had the highest solubility in water solutions of NADES composed of choline chloride (ChCl) and citric acid (CA). The solubility of MNZ (expressed as 103 mol fraction) increased with the concentration of ChCl:CA NADES (from 6.7743 to 26.8518 at 298.5 K, for 30 and 70 wt% NADES-water mixtures, respectively), and it was more effective when compared to aqueous solutions of individual NADES components with wt% corresponding to these in the NADES-water mixtures. The study also found a preferable mixing of MNZ with aqueous solutions of NADES reflected by negative values of standard molar enthalpy change of mixing (approx. − 4.2 kJ·mol−1), compared with positive values in the case of MNZ mixing with water or ChCl aqueous solutions (approx. 7.3 kJ·mol−1). Comparative research conducted on the volume and acoustics of MNZ in water and aqueous solutions of ChCl, CA, and ChCl:CA NADES also confirmed stronger interactions between the drug and NADES and CA. The dominant interactions between MNZ and co-solvent were hydrophilic-hydrophobic and hydrophobic-hydrophobic. This effect increased in the following strength order: ChCl < NADES < CA. In conclusion, the obtained NADES seems to be a promising co-solvent which provides solid grounds for further research to evaluate the full potential in pharmaceutical design of MNZ liquid formulations.
Solvation phenomena in ternary system tetramethylurea-methylacetamide-water: Insights from volumetric, compressibility and FTIR analysis
- Jarosław Wawer
- Emilia Kaczkowska
- Magdalena Tyczyńska
- Małgorzata Jóźwiak
- Joanna Krakowiak
2024 JOURNAL OF MOLECULAR LIQUIDS
The properties of the ternary systems N,N,N’,N’-tetramethylurea - N-methylacetamide - water were investigated using Fourier-transform infrared spectroscopy (FTIR), volumetric and compression measurements. Densities and sound velocities were determined in order to obtain the apparent molar volumes (VΦ) and apparent molar isentropic compressions (ΚS,Φ). These values were then extrapolated to infinite dilution. Additionally, interaction parameters were calculated from the McMillan-Mayer theory. The studies were conducted at 288.15, 298.15, and 308.15 K, at atmospheric pressure (0.1 MPa). The concentration ranges of N-methylacetamide were 2, 4, 6, and 8 moles per kilogram of pure water, and for N,N,N’,N’-tetramethylurea from 0 to around 0.35 moles per kilogram of solvent. Discrete changes in isentropic compression were observed. This is the result of the alignment of plots of ΚS,Φ 0 as a function of NMA concentration. The results for N,N,N’,N’-tetramethylurea were compared with analogous data for the system containing n-butylurea, which is an isomeric compound but exhibits different hydration behaviour. Additionally, large volumetric interaction coefficients were observed, indicating strong interactions between urea derivatives and NMA. This suggests the possibility of strong interactions between protein destabilizers and the protein backbone, differing from those observed for protein structure stabilizers. The observation contributes to understanding the mechanism of osmolyte action and their influence on protein stability.
Sonocatalytic degradation of Bisphenol A from aquatic matrices over Pd/CeO2 nanoparticles: Kinetics study, transformation products, and toxicity
- Alexandra A. Ioannidi
- Georgios Bampos
- Maria Antonopoulou
- Paula Oulego
- Grzegorz Boczkaj
- Dionisios Mantzavinos
- Zacharias Frontistis
2024 SCIENCE OF THE TOTAL ENVIRONMENT
In this work, different ratios of palladium – cerium oxide (Pd/CeO2) catalyst were synthesized and characterized, while their sonocatalytic activity was evaluated for the degradation of the xenobiotic Bisphenol A (BPA) from aqueous solutions. Sonocatalytic activity expressed as BPA decomposition exhibited a volcano-type behavior in relation to the Pd loading, and the 0.25Pd/CeO2 catalyst characterized by the maximum Pd dispersion and lower crystallite size demonstrated the higher activity. Using 500 mg/L of 0.25 % Pd/CeO2 increased the kinetic constant for BPA destruction by more than two times compared to sonolysis alone (20 kHz at 71 W/L). Meanwhile, the simultaneous use of ultrasound and a catalyst enhanced the efficiency by 50.1 % compared to the sum of the individual processes, resulting in 95 % BPA degradation in 60 min. The sonocatalytic degradation of BPA followed pseudo-first-order kinetics, and the apparent kinetic constant was increased with ultrasound power and catalyst loading, while the efficiency was decreased in bottled water and secondary effluent. From the experiments that were conducted using appropriate scavengers, it was revealed that the degradation mainly occurred on the bubble/liquid interface of the formed cavities, while the reactive species produced from the thermal or light excitation of the prepared semiconductor also participated in the reaction. Five first-stage and four late-stage transformation products were identified using UHPLC/TOF-MS, and a pathway for the sonocatalytic degradation of BPA was proposed. According to ECOSAR software prediction, most transformation by-products (TBPs) present lower ecotoxicity than the parent compound, although some remain toxic to the indicators chosen.
Sonochemical Based Processes for Treatment of Water and Wastewater
- Kirill Fedorov
- Manoj P Rayaroth
- Xun Sun
- Reza Darvishi
- Shirish H. Sonawane
- Noor S. Shah
- Varsha Srivastava
- Zhaohui Wang
- Grzegorz Boczkaj
2024
Sonochemical Based Processes for Treatment of Water and Wastewater - Opportunities and Challenges – A Future Perspective.
Sorbents modified by deep eutectic solvents in microextraction techniques
- Patrycja Makoś-Chełstowska
- Jacek Gębicki
2024 TRAC-TRENDS IN ANALYTICAL CHEMISTRY
In recent years, considerable attention has been directed towards the employment of green solvents, specifically deep eutectic solvents (DES), in liquid phase microextraction techniques. However, comprehensive and organized knowledge regarding the modification of sorbent surface structures with DES remains limited. Therefore, this paper reviews the application of DES in modifying and improving the properties of sorbents for microextraction techniques. The review begins by explaining the criteria for selecting DES as surface modifiers and the types of sorbents. Subsequently, it delves into the diverse techniques employed to modify sorbents using DES, including dip coating, sol-gel coating, polymer monolith coatings, molecular imprinting, electrochemical deposition, and simultaneous DES formation and sorbent impregnation. The impact of these modifications on sorbent selectivity, and durability, extraction efficiency, and environmental sustainability is critically evaluated. Additionally, this paper discusses the applications of DES-modified sorbents in various types of solid-phase extraction and solid-phase microextraction techniques. The review concludes with a discussion of current challenges and future perspectives in the field, including potential avenues for further research.
Sounding Mechanism of a Flue Organ Pipe—A Multi-Sensor Measurement Approach
- Paolo Bordoni
- Piotr Odya
- Józef Kotus
- Bożena Kostek
2024 Pełny tekst SENSORS
This work presents an approach that integrates the results of measuring, analyzing, and modeling air flow phenomena driven by pressurized air in a flue organ pipe. The investigation concerns a Bourdon organ pipe. Measurements are performed in an anechoic chamber using the Cartesian robot equipped with a 3D acoustic vector sensor (AVS) that acquires both acoustic pressure and air particle velocity. Also, a high-speed camera is employed to observe the jet coming out from the windway. For that purpose, the steam resulting from dry ice and hot water is used. A numerical simulation of the sounding mechanism of a pipe of the same geometry is based on measuring the pressure signal and the intensity field around the mouth employing an intensity probe and visualizing and observing the motion of the air jet, which represents the excitation mechanism of the system. The ParaVIEW software serves for the simulation and visualization of the air jet. Then, the results obtained from measurements and simulations are compared and discussed. Also, some future directions discussing the application of a machine-learning approach to the area of pipe organ air flow investigation are contained in the Conclusions section.
sp2-rich dendrite-like carbon nanowalls as effective electrode for environmental monitoring of explosive nitroaromatic
- Anna Dettlaff
- Małgorzata Szopińska
- Daniel Houghton
- Piotr Prasuła
- Yisong Han
- Marc Walker
- Geoff West
- Agata Kamieńska-Duda
- Sylwia Fudala-Książek
- Michał Sobaszek
2024 Pełny tekst CHEMICAL ENGINEERING JOURNAL
Nitroaromatic compounds are commonly used explosive materials that pose a risk to human health and ecosystems due to their acute toxicity and carcinogenicity. Nitroaromatics have numerous pathways into the environment via discarded munitions (e.g. into the Baltic Sea after World War II), after use in mining operations, and in industrial run-off from factories producing these compounds (which are produced across the world to date). The current detection method relies on chromatography and mass spectrometry methods, which are time-consuming, expensive, and require specialist equipment and training. Carbon-based electrochemical sensors offer a low-cost, fast, and easy on-site method for the detection of a variety of compounds. This study demonstrates an efficient approach for rapid electrochemical sensing of Tetryl (N-methyl-N-2,4,6-tetranitroaniline) through the use of boron-doped sp2-rich carbon structures. These structures, known as dendrite-like carbon nanowalls (D:CNW), were fabricated in one-step deposition and extensively characterized to understand the structure and surface chemistry. Electrodes were used to detect a range of nitroaromatic compounds, most notably tetryl in both laboratory and real environmental samples, with an excellent sensitivity of 153.0 µA cm−2 ppm−1 and a detection limit of 17 ppb. The analytical and electrochemical capabilities of D:CNW electrodes indicate their suitability for extensive environmental monitoring.
Spatial variability of the hydrochemistry of shallow groundwaters and surface waters of the Rensdyrbekken: A case study of a permafrost catchment in Bellsund (SW Spitsbergen, Svalbard)
- Sara Lehmann-konera
- Piotr Zagorski
- Kamil Nowinski
- Krzysztof Raczynski
- Marcin Frankowski
- Łukasz Franczak
- Mateusz Dobek
- Danuta Szumińska
- Ruman Marek
- Ramia Bakain Al
- Żaneta Polkowska
2024 Pełny tekst LAND DEGRADATION & DEVELOPMENT
Progressive climate change may have unpredictable consequences for the Arctic environment. Permafrost catchments off the west coast of Svalbard, described as “thin” and “warm,” are particularly sensitive to climate change. The interdisciplinary research on the hydrochemical response of surface and underground water functioning within a small permafrost catchment area focused on the determination of the impact of meteorological conditions (temperature (T), precipitation (P)) on the mean daily discharge (Q), and the lowering of the groundwater table (H). We determined physical and chemical properties (pH and SEC) and concentrations of major elements (Ca, Mg, Na, K) and 23 trace elements (i.a. Cd, Cu, Hg, Pb, Zn) in 280 water samples. The results of the correlation matrix showed that an increase in the average air temperature in the summer of 2021 had a significant impact on the hydrochemistry of both types of waters operating in the catchment. In response to increase in T, the lowering of the H (0.52 < r < 0.66) and a decrease in Q (0.66 < r < 0.68) were observed what in consequence also leads to changes in water chemistry. The principal component analysis (CA) indicates that chemical weathering and binding of elements to DOC are processes influencing water chemistry. Results of statistical analysis showed that the resultant of the hydrometeorological conditions that prevailed in that season and the type of geological formations on which they were located had a significant impact on the water chemistry at individual measurement points. Significant differences in the concentrations of elements between points on the same geological formations were also found.
Specification-Oriented Automatic Design of Topologically Agnostic Antenna Structure
- Adrian Bekasiewicz
- Mariusz Dzwonkowski
- Tom Dhaene
- Ivo Couckuyt
2024
Design of antennas for modern applications is a challenging task that combines cognition-driven development of topology intertwined with tuning of its parameters using rigorous numerical optimization. However, the process can be streamlined by neglecting the engineering insight in favor of automatic de-termination of structure geometry. In this work, a specification-oriented design of topologically agnostic antenna is considered. The radiator is developed using a bi-stage algorithm that involves min-max classification of randomly-generated topologies followed by local tuning of the promising designs using a trust-region optimization applied to a feature-based representation of the structure frequency response. The automatically generated antenna is characterized by –10 dB reflection for over 600 MHz around the center frequency of 6.5 GHz and a dual-lobe radiation pattern. The obtained performance figures make the radiator of use for in-door positioning applications. The design method has been favorably compared against the frequency-based trust-region optimization.
Spectroscopic studies on physicochemical properties of selected unsymmetrical bisacridine derivatives and NMR analysis of their interactions with the model sequence Pu22 aided by molecular dynamics
- Michał Kosno
2024 Pełny tekst
In recent years, new promising acridine derivatives have appeared, belonging to the unsymmetrical bisacridines (UAs) family with high anticancer activity. Both their physicochemical properties and their mechanism of action at the molecular level have not been thoroughly analyzed so far. Four derivatives were selected for the study, termed as: C-2028, C-2041, C-2045 and C-2053. The first aim of this work was to determine the protonation forms in which the studied compounds exist at different pH. The second aim was the analysis of aggregation process at different conditions. Methods such as UV-Vis and NMR spectroscopy were used for this purpose. The obtained spectral data were subjected to a thorough chemometric analysis, using techniques such as principal components analysis, multiple regression and numerical optimization. Previous studies have shown that a potential molecular target for unsymmetrical bisacridines may be the promoter sequence of the C-Myc proto-oncogene, known as Pu22. Next goal of the presented work was to determine the interactions of the studied compounds with the above mentioned sequence using advanced NMR spectroscopy and molecular dynamics methods. These studies were narrowed down to the two most promising derivatives: C-2045 and C-2053. In order to determine the exact molecular structure of the obtained complexes, a series of one- and two-dimensional NMR spectra of both investigated compounds and their monomeric derivatives (C-1311 and C-1748) were recorded, which allowed to build the initial structures of the studied complexes. In the next step, they were subjected to an equilibrium MD simulation. In the final stage of the research, the nature and strength of the interactions between the studied compounds and the selected G-quadruplex were estimated using the umbrella sampling method, which allowed the determination of the free energy profiles of the obtained complexes. The results obtained allowed to determine the way in which the unsymmetrical bisacridines interact with the C-Myc promoter sequence - their potential molecular target. In addition, their basic physicochemical properties have been determined, which will allow further research on the compounds described above. In this work, a simple and reliable method for the determination of physicochemical constants has been developed and presented, which yields well credible results, even in the case of compounds with a complex structure having many sites capable of protonation.
Sport as a Tool for the Development of Healthy and Sustainable Cities: A Strategic Documentation Review
- Aleksander Orłowski
- Narek Parsamyan
2024
The rapidly changing cities and their environment are causing new challenges for which actions and solutions must be sought. Most of all, a major challenges facing cities are adverse environmental changes and issues related to public health and citizens well-being. Sport is present in the lives of most of us and is an essential component of urban infrastructure, while in relation to this, to what extent is it being used to support health and sustainable goals, shaping cities of tomorrow. The area of relevance of sport for healthy and sustainable cities has not been explored in depth so far. The study aims to examine the sport dimensions and sport factors that contribute to healthy and sustainable city frameworks, through a literature review and analysis of international institutions' policy documents and metrics. The study will contribute to broader understanding of the role of sport within the framework of healthy and sustainable cities and creates the paradigm of future considerations of the relevance of sport from the perspective of city management and policy maker. The novelty of this study is the use of primary sources (strategic documents) for analysis, being a relevant step for the further process of identifying the sport role towards healthy and sustainable cities.
Sport-related concussion alters cerebral hemodynamic activity during controlled respiration
- Cody A. Ellingson
- Jyotpal Singh
- Chase J. Ellingson
- M. Abdullah Shafiq
- Luke W. Sirant
- Kim D. Dorsch
- Marcin Gruszecki
- Gregory Kratzig
- J Neary
2024 JOURNAL OF NEUROPHYSIOLOGY
This study investigated cerebral hemodynamic activity following sport-related concussion. Prefrontal cortex oxygenation was assessed by near-infrared spectroscopy (NIRS) during a controlled breathing protocol. Wavelet transformation of the NIRS signals showed significant decreases in HbO2 and HbD amplitude at the respiratory frequency interval (0.10–0.6 HZ) from preseason baseline to acute concussion. These results suggest a decreased respiratory contribution to cerebral hemodynamic activity following acute concussion.
Standardy dostępności do Zintegrowanych Węzłów Przesiadkowych
- Kazimierz Jamroz
- Marek Wysocki
- Jacek Szmagliński
- Romanika Okraszewska
- Łukasz Jeliński
- Anna Gobis
2024
Wiele z istniejących węzłów wymaga integracji pomiędzy poszczególnymi rodzajami transportu pasażerskiego i dostosowania do wymagań osób ze szczególnymi potrzebami, co jest związane z opracowaniem jednolitych standardów dostępności, jednolitej procedury i narzędzi przeprowadzenia oceny dostępności tych węzłów dla OzSP i zaproponowania skutecznych i efektywnych usprawnień. Problemy z samodzielnym i bezproblemowym przemieszczaniem się uwidaczniają się w zależności od klasy i wielkości węzła przesiadkowego (międzynarodowy, krajowy, regionalny, lokalny), jego dostępności, jakości infrastruktury i systemu obsługi. Różnice między przyjętymi rozwiązaniami i stosowanymi udogodnieniami występować mogą nie tylko między węzłami, ale również w obszarze jednego węzła, w zależności od obszaru lub elementu węzła. Sytuacja ta wynika z braku spójnych zasad projektowania obszarów węzłów transportowych traktowanych jako całość, niezależnie od rodzaju podsystemu i odpowiedzialnej jednostki. Nawet w sytuacji stosowania rozwiązań uwzględniających potrzeby poszczególnych grup OzSP, w przypadku braku spójnego podejścia dla niektórych grup – jak np. osoby niewidome – wielość rozwiązań i brak standaryzacji może również stanowić barierę. Dlatego w ramach projektu „Przesiadka bez Barier” podjęto wyzwanie zwiększenia dostępności węzłów przesiadkowych poprzez opracowanie spójnych zasad dla wszystkich elementów Zintegrowanego Węzła Przesiadkowego (budynków, ciągów pieszych, przystanków). Zasady te zebrano i przedstawiono w dokumencie zatytułowanym „Zintegrowane Węzły Przesiadkowe. Standardy Dostępności” (dalej zwanym Standardami Dostępności). Opracowany dokument z jednej strony integruje już istniejące standardy, a dodatkowo rozszerza je o zasady dla miejsc styku infrastruktury poszczególnych rodzajów transportu. Holistyczne podejście, zestawienie zbioru zasad i wytycznych odnoszących się do całego obszaru i wszystkich elementów węzła są podstawą spójnej w skali kraju oceny dostępności ZWP.
Static and dynamic concrete calculations: Breakable aggregates in DEM model
- Michał Nitka
2024 Journal of Building Engineering
The paper deals with the calculations of a 3-point bending beam under static and dynamic loads. The real microstructure was obtained from laboratory tests using micro-tomography images. The quasi-static results were compared directly with experimental data at both macro and micro levels. Subsequently, higher strain rates were applied to investigate dynamic effects. The study focused on the influence of dynamic loading on the macroscopic stress-strain curve, crack propagation, the number of broken contacts, and the distribution of forces and stresses. Special attention was given to micro-fracture and cracking. The calculations were performed using the discrete element method (DEM) and were limited to a 2D problem. The proposed model introduced the consideration of aggregate breakages, which is a novel aspect compared to our previous computations. Fragmentation of the aggregate is particularly important in dynamic tests due to the release of higher energy. Finally, a beam with weak aggregate was used to validate the effectiveness of the model.
Statistical Data Pre-Processing and Time Series Incorporation for High-Efficacy Calibration of Low-Cost NO2 Sensor Using Machine Learning
- Sławomir Kozieł
- Anna Pietrenko-Dąbrowska
- Marek Wójcikowski
- Bogdan Pankiewicz
2024 Pełny tekst Scientific Reports
Air pollution stands as a significant modern-day challenge impacting life quality, the environment, and the economy. It comprises various pollutants like gases, particulate matter, biological molecules, and more, stemming from sources such as vehicle emissions, industrial operations, agriculture, and natural events. Nitrogen dioxide (NO2), among these harmful gases, is notably prevalent in densely populated urban regions. Given its adverse effects on health and the environment, accurate monitoring of NO2 levels becomes imperative for devising effective risk mitigation strategies. However, the precise measurement of NO2 poses challenges as it traditionally relies on costly and bulky equipment. This has prompted the development of more affordable alternatives, although their reliability is often questionable. The aim of this article is to introduce a groundbreaking method for precisely calibrating cost-effective NO2 sensors. This technique involves statistical preprocessing of low-cost sensor readings, aligning their distribution with reference data. Central to this calibration is an artificial neural network (ANN) surrogate designed to predict sensor correction coefficients. It utilizes environmental variables (temperature, humidity, atmospheric pressure), cross-references auxiliary NO2 sensors, and incorporates short time series of previous readings from the primary sensor. These methods are complemented by global data scaling. Demonstrated using a custom-designed cost-effective monitoring platform and high-precision public reference station data collected over five months, every component of our calibration framework proves crucial, contributing to its exceptional accuracy (with a correlation coefficient near 0.95 concerning the reference data and an RMSE below 2.4 µg/m3). This level of performance positions the calibrated sensor as a viable, cost-effective alternative to traditional monitoring approaches.
Statistical Method for Analysis of Interactions Between Chosen Protein and Chondroitin Sulfate in an Aqueous Environment
- Piotr Weber
- Piotr Bełdowski
- Adam Gadomski
- Krzysztof Domino
- Piotr Sionkowski
- Damian Ledziński
2024
We present the statistical method to study the interaction between a chosen protein and another molecule (e.g., both being components of lubricin found in synovial fluid) in a water environment. The research is performed on the example of univariate time series of chosen features of the dynamics of mucin, which interact with chondroitin sulfate (4 and 6) in four different saline solutions. Our statistical approach is based on recurrence methods to analyze chosen features of molecular dynamics. Such recurrence methods are usually applied to reconstruct the evolution of a molecular system in its reduced phase space, where the most important variables in the process are taken into account. In detail, the analyzed time-series are spitted onto sub-series of records that are expected to carry meaningful information about the system of molecules. Elements of sub-series are splinted by the constant delay-time lag (that is the parameter determined by statistical testing in our case), and the length of sub-series is the embedded dimension parameter (using the Cao method). We use the recurrent plots approach combined with the Shannon entropy approach to analyze the robustness of the sub-series determination. We hypothesize that the robustness of the sub-series determines some specifics of the dynamics of the system of molecules. We analyze rather highly noised features to demonstrate that such features lead to recurrence plots that graphically look similar. From the recurrence plots, the Shannon entropy has been computed. We have, however, demonstrated that the Shannon entropy value is highly dependent on the delay time value for analyzed features. Hence, elaboration of a more precise method of the recurrence plot analysis is required. For this reason, we suggest the random walk method that can be applied to analyze the recurrence plots automatically.
Stiffness assessment of the laminate recovered from end-of-life wind turbine blade
- Łukasz Pyrzowski
- Agnieszka Sabik
- Jacek Kluska
- Jakub Zembrzuski
2024 COMPOSITE STRUCTURES
In the paper the stiffness parameters of the laminate recovered from an aerodynamic shell of a decommissioned wind turbine blade are evaluated. The aim of the work is to assess selected methods for identifying material data, as well as to estimate the level of stiffness degradation during turbine operation. Several practical identification methods are presented and compared. Two concepts of a single laminate layer are considered, global and local. The global concept assumes that the equivalent layer of the laminate is a system of three physical layers of a single triaxial fabric. The local concept takes into account all physical layers of the laminate. The material parameters of the global layer are identified and validated in experimental tests. Data for individual physical layers are determined by inverse analysis and the rule of mixtures. The compliance of the results obtained allows one to conclude that the stiffness of the material did not degrade significantly during the operation period. The stiffness parameters of the laminate have shown that the tested material is still very attractive for structural purposes.
Storage of High-Strength Steel Flux-Cored Welding Wires in Urbanized Areas
- Adrian Wolski
- Aleksandra Świerczyńska
- Grzegorz Lentka
- Dariusz Fydrych
2024 Pełny tekst International Journal of Precision Engineering and Manufacturing-Green Technology
The condition of the consumables is a key factor determining the waste reduction in the welding processes and the quality of the welded joint. The paper presents the results of tests of four types of fux-cored wires dedicated for welding high-strength steels, stored for 1 month and 6 months in Poland in two urbanized areas: in a large seaside city (Gdańsk) and in Warsaw, located in the center of the country. The wires were subjected to macroscopic and microscopic (stereoscopic, SEM) observations, EDS analysis, technological tests assessing elastic properties and targetability. The degree of degradation of the wires was also tested using resistance measurements. In order to assess the efect of storing wires on the weldability of steel, the difusible hydrogen content in deposited metal was determined by high-temperature extraction. It was found that the storage caused changes in the surface condition of the wires, afected their elasticity and electrical properties, which afects the behavior of the wires during welding. A signifcant infuence of storage conditions on the hydrogenation of deposited metal was found: in the case of three types of wires, the level of low hydrogen processes was exceeded and the maximum result was 15.18 ml/100 g of deposited metal. It was also found that copper-plated wire showed a signifcantly increased resistance to storage conditions compared to non-copper-plated wires.