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Liquid chromatography techniques for separation of flavonoids from Droseraceae
PublikacjaFlavonoids which are presented in insectivorous plants of the Droseraceae family have wide range of advantageous properties i.e. an antioxidant, anti-inflammatory and antimicrobial activities, antitumor activity was reported as well.The purpose of the research was to develop the most favourable conditions for liquid chromatographic separation and identification of myricetin and quercetin in extracts of insectivorous plants. In...
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Concentrations of alfa- and gamma- tocopherols in human breast milk during the first months of lactation and in infant formulas
PublikacjaThe aim of this study was to determine the concentrations of alpha- and gamma-tocopherols in human breast milk samples from different periods of lactation and to compare them with tocopherol content in commercially available formulas for infants at corresponding ages. The study included 93 breast milk samples obtained on the 2nd (colostrum, n=17), 14th (n=30), 30th (n=27) and 90th day of lactation (n=19), along with 90 samples...
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Variable-Fidelity Simulation Models and Sparse Gradient Updates for Cost-Efficient Optimization of Compact Antenna Input Characteristics
PublikacjaDesign of antennas for the Internet of Things (IoT) applications requires taking into account several performance figures, both electrical (e.g., impedance matching) and field (gain, radiation pattern), but also physical constraints, primarily concerning size limitation. Fulfillment of stringent specifications necessitates the development of topologically complex structures described by a large number of geometry parameters that...
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Formation of Highly Conductive Boron-Doped Diamond on TiO2 Nanotubes Composite for Supercapacitor or Energy Storage Devices
PublikacjaIn the present paper, we report the phenomena of the formation of the novel composite nanostructures based on TiO2 nanotubes (NTs) over-grown by thin boron-doped diamond (BDD) film produced in Microwave Plasma Enhanced Chemical Vapor Deposition (PE MWCVD). The TiO2 nanotube array overgrown by boron-doped diamond immersed in 0.1 M NaNO3 can deliver high specific capacitance of 7.46 mF cm−2. The composite electrodes were characterized...
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Fabrication and characterization of composite TiO2 nanotubes/ boron-doped diamond electrodes towards enhanced supercapacitors
PublikacjaThe composite TiO2 nanotubes / boron-doped diamond electrodes were deposited using Microwave Plasma Enhanced Chemical Vapor Deposition resulting in the improved electrochemical performance. This composite electrode can deliver high specific capacitance of 7.46 mF cm‐− 2 comparing to boron-doped diamond (BDD) deposited onto flat Ti plate (0.11 mF cm‐− 2).The morphology and composition of composite electrode were characterized...
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Controlling the size and morphology of precipitated calcite particles by the selection of solvent composition
PublikacjaCalcium carbonate particles were obtained in the reaction of calcium hydroxide with carbon dioxide at 65°C. Initial Ca(OH)2 suspensions were prepared in pure water and aqueous solutions of ethylene glycol or glycerol of the concentration range up to 20% (vol.). The course of reaction was monitored by conductivity measurements. Precipitated solids were analyzed by FTIR, XRD, SEM and the particles size distribution was determined...
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Unravelling the role of electron–hole pair spin in exciton dissociation in squaraine-based organic solar cells by magneto-photocurrent measurements
PublikacjaA high absorption coefficient and narrow absorption bands in squaraine (SQ) dyes have resulted in rapidly growing interest in them as a donor material in photovoltaic devices. The exciton dissociation process in organic systems proceeds via a multistep mechanism where the electron–hole pairs (charge transfer states) involved in the current generation process determine the recombination losses and subsequently limit the overall...
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DETERMINATION OF SEAKEEPING PERFORMANCE FOR A CASE STUDY VESSEL BY THE STRIP THEORY METHOD
PublikacjaThe increase of seakeeping performance is of particular importance for car and passenger ferries, service ships in the gas and oil extraction industry and offshore wind power farm industry, as well as for special purpose ships (including military applications). In the water areas of the Baltic Sea, North Sea, and Mediterranean Sea, which are characterised by a short and steep wave, the hull shape has a substantial impact on the...
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Optimization of carbamazepine photodegradation on defective TiO2-based magnetic photocatalyst
PublikacjaIn this work, carbamazepine (CBZ) degradation over defective Fe3O4@SiO2/d-TiO2/Pt photocatalyst was studied. Within the titania structure, Ti vacancies and Pt nanoparticles were introduced to enhance the photocatalyst’s light absorption and influence charge carriers’ mobility. For the carbamazepine degradation, process parameters, e.g., temperature, flux intensity, photocatalyst loading, aeration, pH, and addition of H2O2, were optimized...
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GTR/Thermoplastics Blends: How Do Interfacial Interactions Govern Processing and Physico-Mechanical Properties?
PublikacjaIn this work, GTR/thermoplastics blends (in ratio 50/50 and 75/25 wt.%) were prepared by melt-compounding in an internal mixer. During research, trans-polyoctenamer rubber (TOR), ethylene-vinyl acetate copolymer (EVA), ethylene-octene copolymer (EOC), and linear low-density polyethylene (LLDPE), were used in their thermoplastic phase. Microstructure and processing-performance property interrelationships of the studied materials...
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Direction of Arrival Estimation Based on Received Signal Strength Using Two-Row Electronically Steerable Parasitic Array Radiator Antenna
PublikacjaIn this paper, we present a novel approach to direction-of-arrival (DoA) estimation using two-row electronically steerable parasitic array radiator (ESPAR) antenna which has 12 passive elements and allows for elevation and azimuth beam switching using a simple microcontroller, relying solely on received signal strength (RSS) values measured at the antenna output port. To this end, we thoroughly investigate all 18 available 3D antenna...
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Open extensive IoT research and measurement infrastructure for remote collection and automatic analysis of environmental data.
PublikacjaInternet of Things devices that send small amounts of data do not need high bit rates as it is the range that is more crucial for them. The use of popular, unlicensed 2.4 GHz and 5 GHz bands is fairly legally enforced (transmission power above power limits cannot be increased). In addition, waves of this length are very diffiult to propagate under field conditions (e.g. in urban areas). The market response to these needs are the...
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Surrogate-assisted EM-driven miniaturization of wideband microwave couplers by means of co-simulation low-fidelity models
PublikacjaThis article proposes a methodology for rapid design optimization of miniaturized wideband couplers. More specifically, a class of circuits is considered, in which conventional transmission lines are replaced by their abbreviated counterparts referred to as slow-wave compact cells. Our focus is on explicit reduction of the structure size as well as on reducing the CPU cost of the design process. For the sake of computational feasibility,...
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Low-Cost Automated Design of Compact Branch-Line Couplers
PublikacjaBranch-line couplers (BLCs) are important components of wireless communication systems. Conventional BLCs are often characterized by large footprints which make miniaturization an important prerequisite for their application in modern devices. State-of-the-art approaches to design of compact BLCs are largely based on the use of high-permittivity substrates and multi-layer topologies. Alternative methods involve replacement of transmission-line...
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Investigation into MPI All-Reduce Performance in a Distributed Cluster with Consideration of Imbalanced Process Arrival Patterns
PublikacjaThe paper presents an evaluation of all-reduce collective MPI algorithms for an environment based on a geographically-distributed compute cluster. The testbed was split into two sites: CI TASK in Gdansk University of Technology and ICM in University of Warsaw, located about 300 km from each other, both connected by a fast optical fiber Ethernet-based 100 Gbps network (900 km part of the PIONIER backbone). Each site hosted a set...
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A hierarchical porous composite magnetic sorbent of reduced graphene oxide embedded in polyvinyl alcohol cryogel for solvent‐assisted‐solid phase extraction of polycyclic aromatic hydrocarbons
PublikacjaA hierarchical porouscomposite magnetic sorbent was fabricated and applied tothe dispersive solvent-assisted solid-phase extraction of five polycyclic aromatichydrocarbons. A sorbent was first prepared by incorporating graphene oxide,calcium carbonate, and magnetite nanoparticles into a polyvinyl alcohol cryo-gel. The graphene oxide was converted to reduced graphene oxide using ascorbicacid and a hierarchical porous structure was...
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Material Design and Optimisation of Electrochemical Li-Ion Storage Properties of Ternary Silicon Oxycarbide/Graphite/Tin Nanocomposites
PublikacjaIn this work, we present the characterization and electrochemical performance of various ternary silicon oxycarbide/graphite/tin (SiOC/C/Sn) nanocomposites as anodes for lithium-ion batteries. In binary SiOC/Sn composites, tin nanoparticles may be produced in situ via carbothermal reduction of SnO2 to metallic Sn, which consumes free carbon from the SiOC ceramic phase, thereby limiting the carbon content in the final ceramic nanocomposite....
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Reduction in Errors in Roughness Evaluation with an Accurate Definition of the S-L Surface
PublikacjaCharacterization of surface topography, roughly divided into measurement and data analysis, can be valuable in the process of validation of the tribological performance of machined parts. Surface topography, especially the roughness, can respond straightly to the machining process and, in some cases, is defined as a fingerprint of the manufacturing. When considering the high precision of surface topography studies, the definition...
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Dissimilar autogenous TIG joint of Alloy 617 and AISI 304H steel for AUSC application
PublikacjaTo reduce costs and improve high-temperature performance in Advanced Ultra Super Critical (AUSC) boilers, it is necessary to weld austenitic steel to Inconel alloy. In this study, the autogenous tungsten inert gas (TIG) welding process was used to join Alloy 617 and an austenitic AISI 304H steel plate of thickness 5 mm. Microstructural analysis showed that the microstructure formation was uneven along the weldments, with columnar...
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Tuning the Laser-Induced Processing of 3D Porous Graphenic Nanostructures by Boron-Doped Diamond Particles for Flexible Microsupercapacitors
PublikacjaCarbon (sp3)-on-carbon (sp2) materials have the potential to revolutionize fields such as energy storage and microelectronics. However, the rational engineering and printing of carbon-on-carbon materials on flexible substrates remains a challenge in wearable electronics technology. This study demon-strates the scalable fabrication of flexible laser-induced graphene (LIG)-boron doped diamond nanowall (BDNW) hybrid nanostructures...
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Potential degradation of norfloxacin using UV-C/Fe2+/peroxides-based oxidative pathways
PublikacjaThe removal of norfloxacin (NOR), a widely used pharmaceutical and emerging water pollutant, was studied using UV-C and Fe2+ catalyzed peroxides-based oxidative processes (e.g., UV-C/Fe2+/H2O2, UV-C/Fe2+/S2O82− and UV-C/Fe2+/HSO5−) and compared with UV-C and UV-C/Fe2+. The UV-C and UV-C/Fe2+ degraded NOR to 38 and 55 %. However, use of peroxides, i.e., H2O2, S2O82−, HSO5− with UV-C and UV-C/Fe2+ promoted NOR %degradation to 75,...
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Reduced-cost optimization-based miniaturization of microwave passives by multi-resolution EM simulations for internet of things and space-limited applications
PublikacjaStringent performance specifications along with constraints imposed on physical dimensions, make the design of contemporary microwave components a truly onerous task. In recent years, the latter demand has been growing in importance, with the innovative application areas such as Internet of Things coming into play. The need to employ full-wave electromagnetic (EM) simu-lations for response evaluation, reliable yet CPU heavy, only...
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AMO model for neuro-inclusive remote workplace
PublikacjaPurpose The aim of this article is to extend current debates on organizational equality, diversity and inclusion to a consideration of neurodivergence in the remote workplace context. Design/methodology/approach Drawing on the ability, motivation, and opportunity (AMO) model and an emerging strength-based approach to neurodiversity, this conceptual paper integrates research on neurodiversity at work and remote working to provide...
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Cost-Efficient Optical Fronthaul Architectures for 5G and Future 6G Networks
PublikacjaFifth-generation and Beyond (5GB) wireless networks have introduced new centralized architectures such as cloud radio access network (CRAN), which necessitate extremely high-capacity low latency Fronthaul (FH). CRAN has many advantageous features in terms of cost reduction, performance enhancement, ease of deployment, and centralization of network management. Nevertheless, designing and deploying a cost-efficient FH is still a...
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The use of Preston equation to determine material removal during lap-grinding with electroplated CBN tools
PublikacjaGrinding executed in a lapping configuration is an alternative finishing process benefiting from both grinding and free-abrasive machining, while minimizing the heat effect impact. Electroplated tools can be effectively used in different abrasive processes, including high-speed grinding, however, the assessment of machining performance over time is a key factor in their correct use to achieve satisfactory technological results....
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Adsorption behavior and corrosion inhibitive characteristics of newly synthesized cyano-benzylidene xanthenes on copper/sodium hydroxide interface: Electrochemical, X-ray photoelectron spectroscopy and theoretical studies
PublikacjaElegant process for synthesis of 3-(7H-dibenzo[c,h]xanthen-7-yl)benzaldehyde (3), as new starting material to create a set of novel xanthene analogues, 2-(3-(7H-dibenzo[c,h]xanthen-7-yl)benzylidene)malononitrile (4), 3-(3-(7H-dibenzo[c,h]xanthen-7-yl)phenyl)-2-cyanoacrylic acid (5), and Ethyl-3-(3-(7H-dibenzo[c,h]xanthen-7-yl)phenyl)-2-cyanoacrylate (6), was achieved starting with available materials under mild conditions. Various...
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Employee Well-Being and its Potential Link With Human Knowledge Risks
PublikacjaEmployee well-being is an essential component of any organisation organisation. Conscious companies make every effort to create a healthy work environment. The well-being of employees and their overall emotional, physical and economic health is affected by various internal and external factors. When employees feel well, they tend to perform better. Therefore, the impact of employee well-being on the organisation is a fact and has...
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On Nature-Inspired Design Optimization of Antenna Structures Using Variable-Resolution EM Models
PublikacjaNumerical optimization has been ubiquitous in antenna design for over a decade or so. It is indispensable in handling of multiple geometry/material parameters, performance goals, and constraints. It is also challenging as it incurs significant CPU expenses, especially when the underlying computational model involves full-wave electromagnetic (EM) analysis. In most practical cases, the latter is imperative to ensure evaluation reliability....
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Recycled rubber wastes-based polymer composites with flame retardancy and electrical conductivity: Rational design, modeling and optimization
PublikacjaPolymer recycling techniques experience a maturity period of design and application. Rubbers comprise a high proportion of polymer wastes, highly flammable and impossible to re-melt. Polymer composites based on ground tire rubber (GTR) and ethylene-vinyl acetate copolymer (EVA) containing carbon black (CB) (1–50 phr), with variable EVA/GTR weight composition (10/90, 25/75, 50/50, 75/25 and 90/10), and processing temperature (Low:...
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Molecular transformation of dissolved organic matter in manganese ore-mediated constructed wetlands for fresh leachate treatment
PublikacjaThe organic matter (OM) and nitrogen in Fresh leachate (FL) from waste compression sites pose environmental and health risks. Even though the constructed wetland (CW) can efficiently remove these pollutants, the molecular-level transformations of dissolved OM (DOM) in FL remain uncertain. This study reports the molecular dynamics of DOM and nitrogen removal during FL treatment in CWs. Two lab-scale vertical-flow CW systems were...
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Carbon dioxide sequestration by industrial wastes through mineral carbonation: Current status and perspectives
PublikacjaMineral carbonation using natural minerals or industrial wastes is a safe and promising strategy for CO2 sequestration. Application of industrial wastes for this purpose has significant ecological and environmental value, which is one of the key green technologies in the global carbon mitigation. This review summarizes the current research status of CO2 mineralization by industrial wastes. This work surveys the mechanisms and capacities...
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PROBLEMY ZWIĄZANE Z ZASTOSOWANIEM NANOTECHNOLOGII W TERMOIZOLACJI BUDYNKÓW
PublikacjaBudownictwo i architektura były zawsze ściśle związane z rozwojem technologicznym a ciągły postęp w badaniach nad inżynierią materiałową pozwalał na uzyskiwanie bardziej wydajnych i wytrzymałych materiałów. Dotyczy to nie tylko elementów konstrukcyjnych budynku ale także technologii związanych z jego wykończeniem. Obecnie coraz większą rolę w budownictwie i architekturze odgrywa pojęcie nanotechnologii. Dziedzina nauki, zdawałoby...
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Rheological, Mechanical, Microstructural and Radiation Shielding Properties of Cement Pastes Containing Magnetite (Fe3O4) Nanoparticles
PublikacjaThis work examines the influence of iron oxide nanoparticles (Fe3O4 NPs) on neutron and gamma-ray radiation shielding characteristics of Portland cement paste. Experimental evaluations were supplemented with theoretical studies using NXCom program. Portland cement pastes with 5, 10, 15, 20, and 30 wt% of nanomagnetite cement replacement were produced. Moreover, rheological, early strength development, compressive strength, and...
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Constrained multi-objective optimization of compact microwave circuits by design triangulation and pareto front interpolation
PublikacjaDevelopment of microwave components is an inherently multi-objective task. This is especially pertinent to the design closure stage, i.e., final adjustment of geometry and/or material parameters carried out to improve the electrical performance of the system. The design goals are often conflicting so that the improvement of one normally leads to a degradation of others. Compact microwave passives constitute a representative case:...
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Expedited Re-Design of Multi-Band Passive Microwave Circuits Using Orthogonal Scaling Directions and Gradient-Based Tuning
PublikacjaGeometry scaling of microwave circuits is an essential but challenging task. In particular, the employment of a given passive structure in a different application area often requires re-adjustment of the operating frequencies/bands while maintaining top performance. Achieving this necessitates utilization of numerical optimization methods. Nonetheless, if the intended frequencies are distant from the ones at the starting point,...
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3D mesoporous α-Co(OH)2 nanosheets electrodeposited on nickel foam: A new generation of macroscopic cobalt-based hybrid for peroxymonosulfate activation
PublikacjaCobalt-based catalysts with high stability and facile recovery for heterogeneous peroxymonosulfate (PMS) activation are still rather sparse and therefore highly desirable. Herein, 3D mesoporous α-Co(OH)2 nanosheets was created on robust nickel foam (NF) via facile electrodeposition approach at 6 mA/cm2 for only 400 s. Almost complete removal of phenol can be achieved within 7 min with a degradation rate of 0.39 min−1, 2 times higher...
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Using Decisional DNA to Enhance Industrial and Manufacturing Design: Conceptual Approach
PublikacjaDuring recent years, manufacturing organizations are facing market changes such as the need for short product life cycles, technological advancement, intense pressure from competitors and the continuous customers’ expectation for high quality products at lower costs. In this scenario, knowledge and its associated engineering/management of every stage involved in the industrial design has become increasingly important for manufacturing...
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Phototransformation of Amlodipine: Degradation Kinetics and Identification of Its Photoproducts
PublikacjaNowadays, monitoring focuses on the primary compounds and does not include degradation products formed during various biological and chemical processes. Transformation products may have the same effects to human health and the environment or sometimes they can be more toxic than the parent compound. Unfortunately, knowledge about the formation of degradation products is still limited, however, can be very important for the environmental...
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Salt melt synthesis of curved nitrogen-doped carbon nanostructures: ORR kinetics boost
PublikacjaImplementing metal-free electrocatalysts for the oxygen reduction reaction (ORR) and revealing crucial chemical or topographical parameters driving their activity are vital for the development of power cells. The carbon-based catalysts are very often synthesized through carbonization of biopolymers, in particular, those one containing nitrogen groups such as chitosan. Unfortunately, the resulting carbonaceous materials usually...
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Enhanced solar light photocatalytic performance of Fe-ZnO in the presence of H2O2, S2O82−, and HSO5− for degradation of chlorpyrifos from agricultural wastes: Toxicities investigation
PublikacjaThis study reported Fe doped zinc oxide (Fe-ZnO) synthesis to degrade chlorpyrifos (CPY), a highly toxic organophosphate pesticide and important sources of agricultural wastes. Fourier transform infrared, X-ray diffraction, scanning electron microscope, and energy-dispersive X-ray spectroscopic analyses showed successful formation of the Fe-ZnO with highly crystalline and amorphous nature. Water collected from agricultural wastes...
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Recent progress in ultra-low formaldehyde emitting adhesive systems and formaldehyde scavengers in wood-based panels: a review
PublikacjaTraditional wood-based panels are produced with synthetic, formaldehyde-based adhesives, commonly made from fossil-derived constituents, such as urea, phenol, melamine, etc. Along with their numerous advantages, such as chemical versatility, high reactivity and excellent adhesive performance, these adhesives are characterized by certain problems, connected with the hazardous volatile organic compounds (VOCs), mostly free formaldehyde...
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Balanced Spider Monkey Optimization with Bi-LSTM for Sustainable Air Quality Prediction
PublikacjaA reliable air quality prediction model is required for pollution control, human health monitoring, and sustainability. The existing air quality prediction models lack efficiency due to overfitting in prediction model and local optima trap in feature selection. This study proposes the Balanced Spider Monkey Optimization (BSMO) technique for effective feature selection to overcome the local optima trap and overfitting problems....
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Interpretable deep learning approach for classification of breast cancer - a comparative analysis of multiple instance learning models
PublikacjaBreast cancer is the most frequent female cancer. Its early diagnosis increases the chances of a complete cure for the patient. Suitably designed deep learning algorithms can be an excellent tool for quick screening analysis and support radiologists and oncologists in diagnosing breast cancer.The design of a deep learning-based system for automated breast cancer diagnosis is not easy due to the lack of annotated data, especially...
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Quality control of cheese samples for the presence of natamycin preservative – A natural deep eutectic solvent (NADES) based extraction coupled with HPLC
PublikacjaA new protocol for the determination of natamycin – an antifungal agent used as a food preservative - in cheese samples – is described. This new method is based on a natural deep eutectic solvent (NADES) green extraction procedure. High-performance liquid chromatography (HPLC) was used for detection and quantification. NADESs with different molar ratios were evaluated for efficient and selective extraction. NADES made of thymol...
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Machine-Learning-Based Global Optimization of Microwave Passives with Variable-Fidelity EM Models and Response Features
PublikacjaMaximizing microwave passive component performance demands precise parameter tuning, particularly as modern circuits grow increasingly intricate. Yet, achieving this often requires a comprehensive approach due to their complex geometries and miniaturized structures. However, the computational burden of optimizing these components via full-wave electromagnetic (EM) simulations is substantial. EM analysis remains crucial for circuit...
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Nanofiltration-Assisted Concentration Processes of Phenolic Fractions and Carotenoids from Natural Food Matrices
PublikacjaIn new food formulations, carotenoids and phenolic compounds are likely to be the most sought after food ingredients according to their bioactivity, nutraceutical, nutritional value, and compatibility properties once incorporated into food formulations. Such solutes are naturally present in many plant-based sources, and some portions are directly consumed when enriching food products and formulations; however, some portions, which...
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Crystalline Silicon (c-Si)-Based Tunnel Oxide Passivated Contact (TOPCon) Solar Cells: A Review
PublikacjaContact selectivity is a key parameter for enhancing and improving the power conversion efficiency (PCE) of crystalline silicon (c-Si)-based solar cells. Carrier selective contacts (CSC) are the key technology which has the potential to achieve a higher PCE for c-Si-based solar cells closer to their theoretical efficiency limit. A recent and state-of-the-art approach in this domain is the tunnel oxide passivated contact (TOPCon)...
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A new index for statistical analyses and prediction of travelling ionospheric disturbances
PublikacjaTravelling Ionospheric Disturbances (TIDs) are signatures of atmospheric gravity waves (AGWs) observed in changes in the electron density. The analysis of TIDs is relevant for studying coupling processes in the thermosphere–ionosphere system. A new TID index is introduced, which is based on an easy extension of the commonly used approach for TID detection. This TID activity index, which can be applied for individual Global Navigation...
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Design of novel highly sensitive sensors for crack detection in metal surfaces: theoretical foundation and experimental validation
PublikacjaThe application of different types of microwave resonators for sensing cracks in metallic structures has been subject of many studies. While most studies have been focused on improving the sensitivity of planar crack sensors, the theoretical foundation of the topic has not been treated in much detail. The major objective of this study is to perform an exhaustive study of the principles and theoretical foundations for crack sensing...
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Multi-Analytical Techniques for the Study of Burial Clothes of Polish King Sigismund III Vasa (1566–1633) and His Wife Constance Habsburg (1588–1631)
PublikacjaThe subjects of this research are the burial clothes of Polish King Sigismund III Vasa and his wife Constance, which were woven and embroidered with silk and metal threads. Fragments of the textiles underwent spectroscopic, spectrometric, and thermogravimetric analyses. The hydrofluoric acid extraction method was improved to isolate various classes of dyes from the textile samples that had direct contact with human remains. High-performance...