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Activity of Patents in Fuel Cells and Hydrogen Production in the Context of Passenger Car Fleet in the V4 Countries
PublikacjaThe hydrogen market in the world today is capable ovule and em-pirical evidence on activity of patents in fuel cells and hydrogen production islimited so far. Patent applications in zero-emission mobility in the aspect of fuelcells include: DAFC/DMFC&DMFC, PEMFC, SOFC, AFC, PAFC. As for thepatents relating to the hydrogen production, they concern low carbon, electrol-ysis and inorganic. The purpose of the study was to investigate...
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Feedline Alterations for Optimization-Based Design of Compact Super-Wideband MIMO Antennas in Parallel Configuration
PublikacjaThis letter presents a technique for size reduction of wideband multiple-input-multiple-output (MIMO) antennas. Our approach is a two-stage procedure. At the first stage, the antenna structure is modified to improve its impedance matching. This is achieved through incorporation of an n-section tapered feedline, followed by reoptimization of geometry parameters. Reducing the maximum in-band reflection well beyond the acceptance...
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Broad Stopband, Low-Loss, and Ultra-Compact Dual-Mode Bandpass Filter Based on HMSIRC
PublikacjaIn this investigation, an ultra-compact dual-mode bandpass filter (BPF) with a wide stopband re-sponse is realized by using a half-mode substrate-integrated rectangular cavity (HMSIRC). The HMSIRC resonator is designed with a cavity that is rectangular in shape and has metallic vias along three of the sides. The fourth side is open-ended and contains microstrip feed lines. For the purpose of constructing a magnetic wall, a rectangular...
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Compact Quasi-Elliptic-Type Inline Waveguide Bandpass Filters With Nonlinear Frequency-Variant Couplings
PublikacjaThis work presents the design techniques to synthesize a class of compact inline quasi-elliptic-type waveguide cavity bandpass filters based on novel nonlinear frequency-variant couplings (NFVCs). These highly dispersive frequency-variant couplings (FVCs) are realized by means of a pair of partial-height posts that are placed at the junctions between every two cavity resonators. Each NFVC produces a transmission pole in between...
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Design and Optimization of a Compact Super-Wideband MIMO Antenna with High Isolation and Gain for 5G Applications
PublikacjaThis paper presents a super-wideband multiple-input multiple-output (SWB MIMO) antenna with low profile, low mutual coupling, high gain and compact size for microwave and millimeter wave (mm-wave) fifth-generation (5G) applications. A single antenna is a simple elliptical-square shape with a small physical size of 20 × 20 × 0.787 mm3. The combination of both square and elliptical shapes results in an exceptionally broad impedance...
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Current trends in consumption of multimedia content using online streaming platforms: A user-centric survey
PublikacjaIn its early days, consumption of multimedia content was only possible at a stationary terminal device. The music player was located at home, and had to have a physical drive. Over the last decade, there has been an enormous increase in the number of online streaming platforms. These services enable users to consume rich multimedia content on various devices. Thanks to the widespread and availability of portable devices, any person...
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Abilities, Motivations, and Opportunities of Furloughed Employees in the Context of Covid-19: Preliminary Evidence From the UK
PublikacjaThe Covid-19 global pandemic is a crisis like no other, forcing governments to implement prolonged national lockdowns in an effort to limit the spread of the disease. As organizations aim to adapt and remain operational, employers can suspend or reduce work activity for events related to Covid-19 and claim government support to subsidize employee wages. In this way, some employees are placed on furlough (i.e., temporary unemployment)...
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Rapid multi-objective design optimisation of compact microwave couplers by means of physics-based surrogates
PublikacjaThe authors introduce a methodology for fast multi-objective design optimisation of miniaturised microwave couplers. The approach exploits the surrogate-based optimisation paradigm with an underlying low-fidelity model constructed from an equivalent circuit of the structure under consideration, corrected through implicit and frequency space mapping. A fast prediction tool obtained this way is subsequently optimised by a multi-objective...
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A Compact Self-Hexaplexing Antenna Implemented on Substrate-Integrated Rectangular Cavity for Hexa-Band Applications
PublikacjaThis brief introduces a novel architecture of a compact self-hexaplexing antenna (SHA) implemented on a substrate-integrated rectangular cavity (SIRC) for hexa-band applications. The proposed SHA is configured by using an SIRC resonator, two Pi-shaped slots (PSSs), and six 50Ω microstrip feedlines. The PSSs are connected back-to-back and loaded on top of the SIRC resonator to produce six patch radiators (PRs). The PRs are excited...
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Compact Electromagnetic Lens Antennas Using Cascaded Metasurfaces for Gain Enhancement and Beam Steering Applications
PublikacjaElectromagnetic (EM) lens antenna designs using cascaded metasurfaces for gain enhancement and beam steering applications are proposed. Two different lens aperture designs are proposed and populated with aperiodic unit cells of size 0.2λo × 0.2λo. In lens Design 1, the unit cells of different phases are distributed in concentric circular zones, whereas in lens Design 2, the unit cells of different phases are distributed in vertical...
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Green, simple analytical method for total biogenic amines content determination in wine using spectrophotometry
PublikacjaA simple, green and equitable procedure for total biogenic amines (BAs) content determination was developed. The scientific novelty lies in the use of commercially available S 0378 dye, the reaction of which with BAs results in a colour change of the solution. Sample preparation and analysis were simplified to make the method suitable for routine analyses even in resource-scarce settings. The optimization of the method was carried...
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Comparison of Renewable Energy Sources in ‘New’ EU Member States in the Context of National Energy Transformations
PublikacjaThe European Union strives to create sustainable, low-carbon economies; therefore, energy policies of all member states should move towards renewable energy sources (RES). That concerns also the so-called new EU member states. These countries, on the one hand, are characterized by significant historical similarities in terms of post-communist legacy and adopted development strategies linked with the EU membership, and on the other...
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Optimization-Based Robustness Enhancement of Compact Microwave Component Designs with Response Feature Regression Surrogates
PublikacjaThe ability to evaluate the effects of fabrication tolerances and other types of uncertainties is a critical part of microwave design process. Improving the immunity of the device to parameter deviations is equally important, especially when the performance specifications are stringent and can barely be met even assuming a perfect manufacturing process. In the case of modern miniaturized microwave components of complex topologies,...
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Smartphone-based digital image colorimetry for the determination of total capsaicinoid content in chili pepper extracts
PublikacjaA simple smartphone-based digital image colorimetry was proposed for the determination of total capsaicinoid content and the assessment of chili pepper pungency. The biobased solvent D-limonene was used for the first time to isolate analytes. Capsaicinoids were efficiently separated from chili pepper by solid-liquid extraction with D-limonene followed by partitioning of the analytes into the ammonium hydroxide solution to eliminate...
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Measurements of glucose content in scattering media with time-of-flight technique: comparison with Monte Carlo simulations.
PublikacjaZbadano możliwości pomiaru koncentracji glukozy w materiale silnie rozpraszającym światło z wykorzystaniem techniki czasu przelotu. Badania przeprowadzono wykorzystując ''Intralipid'' będącym fantomem tkanki. Stężenie glukozy wynosiło 100, 200, 300, 500, 1000, 2000,4000 lub 8000 mg/dl. Wyniki pomiarów porównano z wynikami uzyskanymi na drodze modelowania matematycznego.
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Electron-beam irradiation in TEM of hard-segment homopolymers and polyurethanes with different hard-segment content.
PublikacjaZbadano odporność na niszczenie radiacyjne w transmisyjnym mikroskopie elektronowym homopolimeru segmentów sztywnych i poliuretanów z różną zawartością segmentów sztywnych. Dokonano rejestracji morfologii tych polimerów w TEM w trakcie obserwacji w jasnym polu oraz selektywnej dyfrakcji elektronowej. Analizowano tkże te polimery w mikroskopie polaryzacyjnym przed i po obserwacjach w TEM. Potwierdzono doniesienia literatutowe o...
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Experimental study of the fuel jet combustion in high temperature and low oxygen content exhaust gases
PublikacjaPrzeprowadzono badania eksperymentalne spalania pojedynczego strumienia paliwa gazowego. Paliwo podawano współosiowo do generowanych przez konwencjonalny palnik gazowy spalin o wysokiej temperaturze i niskiej zawartości tlenu. Badano wpływ zawartości tlenu w utleniaczu na widzialność płomienia i skład produktów spalania.
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Poland’s energy dependence - economic context
Dane BadawczePoland does not have vast resources of non-renewable energy and no nuclear power plant, therefore the issue of the energy dependence of the state, which affects the level of energy security of the country, is an extremely important factor. It depends on both the volume of imports of energy raw materials and the policy of diversification of sources of...
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Buckling analyses of metal cylindrical silos containing bulk solids during filling
PublikacjaThe paper presents 3D results on stability of thin-walled cylindrical metal silos made of isotropic rolled and corrugated plates containing bulk solids. The behavior of bulk solids was described using a hypoplastic constitutive model. Nonlinear finite element (FE) analyses with both geometric and material nonlinearity were performed with a perfect and an imperfect silo shell wherein initial geometric imperfections were taken into...
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Magdalena Gajewska prof. dr hab. inż.
OsobyMagdalena Gajewska (ur. 1.06.1968 r. w Gdańsku) ukończyła studia w 1993 roku na Wydziale Hydrotechniki Politechniki Gdańskiej. Jest adiunktem w Katedrze Technologii Wody i Ścieków na Wydziale Inżynierii Lądowej i Środowiska Politechniki Gdańskiej. Doktorat (2001) i habilitacja (2013) w dyscyplinie inżynierii środowiska. W kadencji 2016–2020 pełni funkcję prodziekana ds. nauki. Specjalizuję się w technologiach związanych z ekoinżynierią:...
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Jakub Miler dr inż.
OsobyKariera akademicka: 2000: mgr inż. Wydział ETI, Politechnika Gdańska, praca pt. "Computer system for supporting risk management in a software engineering project", promotor prof. Janusz Górski 2005: dr inż. Wydział ETI, Politechnika Gdańska, rozprawa pt. "A Method of Software Project Risk Identification and Analysis", obroniona z wyróżnieniem, dziedzina nauki techniczne, dyscyplina informatyka, promotor prof. Janusz Górski Zainteresowania...
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Finite-difference time-domain analyses of active cloaking for electrically-large objects
PublikacjaInvisibility cloaking devices constitute a unique and potentially disruptive technology, but only if they can work over broad bandwidths for electrically-large objects. So far, the only known scheme that allows for broadband scattering cancellation from an electrically-large object is based on an active implementation where electric and magnetic sources are deployed over a surface surrounding the object, but whose ‘switching on’...
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Interactions of telomeric proteins with nucleic acids: sequence recognition on intact and oxidatively damaged telomeres
PublikacjaTelomeres are complex nucleoprotein assemblies that play a vital role in the maintenance of functional ends of linear chromosomes. Telomeric DNA, composed of tandem repeats of the 5'-TTAGGG-3' motif, solves the so-called end replication problem: as chromosomes shorten with each cell division, no information is lost, and the telomere can be re-extended. In the cell, many protein factors regulate telomere length, nuclear positioning...
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The content of triterpene saponins and phenolic compounds in American ginseng hairy root extracts and their antioxidant and cytotoxic properties
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Microbiological, biochemical and ecotoxicological evaluation of soils in the area of biochar production in relation to polycyclic aromatic hydrocarbon content
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Enzymatic Activity and Content of Polycyclic Aromatic Hydrocarbons (PAHs) in Soils under Low-Stack Emission in Lublin
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Wave propagation analysis in spatial frames using spectral Timoshenko beam elements in the context of damage detection
PublikacjaPraca poświęcona jest zjawisku propagacji fal sprężystych w trójwymiarowych układach ramowych. W ramach teorii belek Timoszenki formułuje się wielowęzłowy element belkowy klasy C0 z sześcioma inżynierskimi stopniami swobody w każdym węźle. Zakłada się, że elementy są wykonane z jednorodnego, izotropowego materiału liniowo sprężystego. Zasadniczym celem artykułu jest sformułowanie szybkiego i wydajnego schematu całkowania po czasie....
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Dynamika układu wieloczłonowego podlegającego więzom opisującym punktowy kontakt pomiędzy układem i nieruchomą krzywką
PublikacjaPraca opisuje zagadnienia modelowania dynamiki układów wieloczłonowych ze skleronomicznymi więzami dwustronnymi. Modelowany układ ma strukturę zamkniętego wieloboku. Zamknięcie struktury wynika z obecności kontaktu pomiędzy układem wieloczłonowym i nieruchomą krzywką. W pracy skoncentrujemy się na równaniach więzów. Rozważania ograniczymy do analizy układów płaskich. Sformułowano ogólna postać równań więzów. Łączy ona równania...
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Content of odd-numbered carbon fatty acids in the milk of lactating women and in infant formula and follow-on formula
PublikacjaBadano zależność pomiędzy występowaniem w mleku ludzkim kwasów pentadekanowego C15:0 (PA) i heptadekanowego C17:0 (HA) a rodzajem diety matek oraz oznaczono zawartość kwasów PA i HA w preparatach do początkowego i następnego żywienia niemowląt, dostępnych w sprzedaży. Badaniu poddano mleko ludzkie uzyskane od 34 zdrowych kobiet w wieku 24-33 lata. Matki podzielono na dwie grupy zgodnie ze spożywana przez nie dietą: grupa kobiet...
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Medical polyurethanes with different hard segments content obtained from polycaprolactone diol, aliphatic diisocyanates and butanediol.
PublikacjaW artykule opisano syntezę 3 serii segmentowych poliuretanów o przeznaczeniu medycznym otrzymanych z polikaprolaktonodiolu, alifatycznych diizocyjanianów: 1,6 heksametylenowego lub 4,4'-dicyklohesametylenowego oraz butanodiolu. Przedstawiono charakterystykę PU uzyskaną na podstawie badania pęcznienia w wodzie, oleju oraz soli fizjologicznej, właściwości powierzchniowych (kąt zwilżania i profilometria), a także badania IR i DSC....
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The Evaluation of Phenolic Acids and Flavonoids Content and Antiprotozoal Activity of Eryngium Species Biomass Produced by Biotechnological Methods
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Building engineering issues in Architectural education in Poland, in context of actual Ministry of Science and Higher Education Regulations
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Comparison of the content of phenolic compounds and antioxidant activity of white, red and black currants (Ribes sp.) extracts
PublikacjaThe aim of this study was to compare the content of antioxidant compounds and the antioxidant activity of extracts from white, red and black currants (Ribes sp.). The chemical properties verified included determinations of anthocyanins and other phenols by HPLC-DAD-MS, total antioxidant activity by standard spectrophotometric tests (ABTS, DPPH and FCR), and profiles of antioxidants by TLC with visualization reagents (ABTS, DPPH,...
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Atomistic Surrogate-Based Optimization for Simulation-Driven Design of Computationally Expensive Microwave Circuits with Compact Footprints
PublikacjaA robust simulation-driven design methodology for computationally expensive microwave circuits with compact footprints has been presented. The general method introduced in this chapter is suitable for a wide class of N-port un-conventional microwave circuits constructed as a deviation from classic design solutions. Conventional electromagnetic (EM) simulation-driven design routines are generally prohibitive when applied to numerically...
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Effect of the Yerba mate (Ilex paraguariensis) brewing method on the content of selected elements and antioxidant potential of infusions
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Corrigendum: Contrast Tempo of Movement and Its Effect on Power Output and Bar Velocity During Resistance Exercise
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The influence of montmorillonite content on change the physicochemical properties of lubricating greases produced from vegetable base oil
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Laboratory Examination of Frost-heaving Properties of Road Unbound Mixtures Based on Fines Content and Plasticity Index
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A Central Composite Design in increasing the quercetin content in the aqueous onion waste isolates with antifungal and antioxidant properties
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Elicitation strategies for the improvement of essential oil content in Rhododendron tomentosum (Ledum palustre) bioreactor-grown microshoots
PublikacjaRhododendron tomentosum Harmaja, previously Ledum palustre L., is a fragrant plant growing in swampy areas, which is characterized by well-known repellent properties and the anti-arthritic potential. In the present study, R. tomentosum microshoots cultivated in RITA® bioreactor, providing the alternative, environment-independent source of the valuable essential oil, were treated for 7 days with copper and nickel salts, methyl jasmonate,...
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Inverse modeling for fast design optimization of small-size rat-race couplers incorporating compact cells
PublikacjaIn the paper, a framework for computationally-efficient design optimization of compact rat-race couplers (RRCs) is discussed. A class of hybrid RRCs with variable operating conditions is investigated, whose size reduction is obtained by replacing ordinary transmission lines with compact microstrip resonant cells (CMRCs). Our approach employs a bottom-up design strategy leading to the development of compact RRCs through rapid design...
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A structure and design optimization of novel compact microscrip dual-band rat-race coupler with enhanced bandwidth
PublikacjaIn the letter, a topology of a novel compact wideband dual-band rat-race coupler has been presented along with its computationally efficient design optimization procedure. Reduction of the circuit size has been achieved by meandering transmission lines of the conventional circuit. At the same time, the number of independent geometry parameters has been increased so as to secure sufficient flexibility of the circuit, necessary in...
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Silicon oxycarbide ceramics as anodes for lithium ion batteries: influence of carbon content on lithium storage capacity
PublikacjaWe report here on the synthesis and characterization of silicon oxycarbide (SiOC) in view of its application as a potential anode material for Li-ion batteries. SiOC ceramics are obtained by pyrolysis of various polysiloxanes synthesized by sol–gel methods. The polysiloxanes contain different organic groups attached to silicon, which influence the chemical composition and the microstructure of the final ceramic product. The structure...
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Effects of La Content on the Densification, Microstructure, and Conductivity of Doped La10−x Ge6 O26±δ Electrolytes
PublikacjaIn this study, the influence of La content on the characteristics of Nb-, Mo-, and W-doped LaxGe6O26±δ electrolytes was investigated through sintering study, X-ray diffraction, scanning electron microscopy, and conductivity measurement. The densification of LaxGe5.5Nb0.5O26±δ and LaxGe5.5W0.5O26±δ was retarded as the x reached 9.75, while that of LaxGe5.5Mo0.5O26±δ improved with increasing La content. The average grain size slightly...
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Broadband Compact Single-Layer Magic-T Junction with Separation of DC Signals between All Ports
PublikacjaA novel structure for a four-port microstrip magic-T junction is presented. The device is composed of microstrip and slotline circuits etched onto two sides of a dielectric substrate. The device is extremely compact and occupies an area more than three times smaller than similar structures recently reported in the literature. The novelty of the device lies in the use of microstrip/slotline transitions for both input ports: summation...
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Effect of User Mobility upon Trust Building among Autonomous Content Routers in an Information-Centric Network
PublikacjaThe capability of proactive in-network caching and sharing of content is one of the most important features of an informationcentric network (ICN). We describe an ICN model featuring autonomous agents controlling the content routers. Such agents are unlikely to share cached content with other agents without an incentive to do so. To stimulate cooperation between agents, we adopt a reputation and trust building scheme that is able...
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Relationships between stakeholder pressure, culture, and CSR-practices in the context of project management in the construction industry in Poland
PublikacjaThe study aims to investigate how CSR-stakeholder pressure, CSR-company culture, and CSR-practices are related to one another based on the example of the construction industry in Poland. This knowledge will make it possible to assess which of the two factors, i.e., stakeholder culture or the internal company culture have a stronger effect on the CSR-practices. To accomplish the goal of the study a sample composed of 216 cases was...
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Low-cost performance-driven modelling of compact microwave components with two-layer surrogates and gradient kriging
PublikacjaUtilization of electromagnetic (EM) simulation tools has become indispensable for reliable evaluation of microwave components. As the cost of an individual analysis may already be considerable, the computational overhead associated with EM-driven tasks that require massive simulations (e.g., optimization) may turn prohibitive. One of mitigation methods is the employment of equivalent network models. Yet, they are incapable of accounting...
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Visegrád countries' scientific productivity in the European context: a 10-year perspective using Web of Science and Scopus
PublikacjaMeasuring the growth of research productivity is a core element of performance in the higher education sector. This paper aims to analyse the scientific productivity of the Visegrád Group countries (2010-2019) based on data from the WoS and Scopus databases as well as data from secondary sources (demographic and socio-economic factors). Quantitatively, although Poland has the highest output, this is due to its comparative size,...
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Shape memory thin films of Polyurethane: Does graphene content affect the recovery behavior of Polyurethane nanocomposites?
PublikacjaThin nanocomposite films of polyurethane have received remarkable attention due to their shape memory properties. As most of the reports focus on the beneficial aspects of the presence of nanofillers such as graphene nanoplatelets (GNPs) introduced into shape memory polymers, some research results reveal the opposite trend. The polyether/polyester-based polyurethane was synthesized through a condensation polymerization and the...