Search results for: TUBULAR HOUSE, CONCRETE SHELL STRUCTURE, INNER THERMAL INSULATION
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Semi-transparent ordered TiO2 nanostructures prepared by anodization of titanium thin films deposited onto the FTO substrate
PublicationIn a significant amount of cases, the highly ordered TiO2nanotube arrays grow through anodic oxidationof a titanium metal plate immersed in electrolyte containing fluoride ions. However, for some practicalapplications, e.g. solar cells or electrochromic windows, the semi-transparent TiO2formed directly onthe transparent, conductive substrate is very much desired. This work shows that high-quality Ti coatingcould be formed at room...
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Novel Cast Polyurethanes Obtained by Using Reactive Phosphorus-Containing Polyol: Synthesis, Thermal Analysis and Combustion Behaviors
PublicationPhosphorus-containing polyol applications in polyurethane synthesis can prevent volatilization of flame retardants and their migration on the surface of a material. In this work, novel cast polyurethanes were prepared by a one-step method with the use of different amounts of phosphorus-containing polyol, 4,4′–diphenylmethane diisocyanate and 1,4-butanediol. The chemical structure, thermal, physicochemical and mechanical properties...
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Synthesis and structure of Bi 5 FeTi 3 O 15 ceramics
PublicationAim of the present research was to fabricate and study crystal structure and phase composition of Bi5FeTi3O15 (BTFO) ceramics exhibiting Aurivillius - type structure. By means of simultaneous thermal analysis and X-ray diffraction analysis the process of synthesis of BTFO ceramics has been studied. Mixed oxide method followed by pressureless sintering was used for ceramics preparation. Three endothermic thermal effects have been...
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Study of nanomechanical properties of (1-y)BST-yMgO thin films
PublicationIn the present study thin films of MgO – modified Ba0.6Sr0.4TiO3 (BST60/40) solid solution were prepared by the sol-gel-type chemical solution deposition method on stainless steel substrates. A multilayer spin-coating approach was utilized for the Ba0.6Sr0.4TiO3-MgO thin film deposition with subsequent thermal annealing at T=650-750C. Dried BST60/40-MgO gel powders were studied with thermogravimetric and differential thermal analysis...
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On the deformation and frequency analyses of SARS-CoV-2 at nanoscale
PublicationThe SARS-CoV-2 virus, which has emerged as a Covid-19 pandemic, has had the most significant impact on people's health, economy, and lifestyle around the world today. In the present study, the SARS-CoV-2 virus is mechanically simulated to obtain its deformation and natural frequencies. The virus under analysis is modeled on a viscoelastic spherical structure. The theory of shell structures in mechanics is used to derive the governing...
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The Influence of Stretch Rod Speed on the Relationship between Preblown Bottle Aesthetic Quality and Final Blown Bottle Thickness Profile in Stretch Blow Molding from Preform Process
PublicationFrom a mechanical point of view, the aesthetic quality of preblown PET bottles and thickness profile of final blown PET bottles manufactured in ISBM process are determined by mechanical and thermal response of blown preforms. From the microscopic point of view the biggest influence on the mechanical and thermal properties of PET bottles have orientation and crystallization processes. From a technological point of view, the aesthetic...
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Solvent Exchange around Aqueous Zn(II) from Ab Initio Molecular Dynamics Simulations
PublicationHydrated zinc(II) cations, due to their importance in biological systems, are the subject of ongoing research concerning their hydration shell structure and dynamics. Here, ab initio molecular dynamics (AIMD) simulations are used to study solvent exchange events around aqueous Zn2+, for which observation in detail is possible owing to the considerable length of the generated trajectory. While the hexacoordinated Zn(H2O)62+ is the...
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Wave Method for Structural Health Monitoring: Testing Using Full-Scale Shake Table Experiment Data
PublicationAn algorithm of the wave method for structural health monitoring (SHM) is tested and calibrated using shake table experiment data of a full-scale, seven-story, reinforced-concrete building slice. The method is based on monitoring changes in the velocity of waves propagating vertically through the structure, identified by least-squares (LSQ) fit of beam models. The experiment was conducted by a team from the University of California,...
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Hydro and marine civil engineering (2023-2024)
e-Learning CoursesKurs realizowany na Wydziale Inżynierii Lądowej i Środowiska (WILiŚ) Politechniki Gdańskiej. Studia: II stopnia - magisterskie, stacjonarne Kierunek: Budownictwo Semestr: 1 (letni) Presentation of basic hydro and marine civil engineering structures together with basic computational procedures for determining environmental forces acting on a structure (vertical-wall breakwater, rubble mound breakwater, submarine pipelines...
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Hydro and marine civil engineering (2020-2021)
e-Learning CoursesKurs realizowany na Wydziale Inżynierii Lądowej i Środowiska (WILiŚ) Politechniki Gdańskiej. Studia: II stopnia - magisterskie, stacjonarne Kierunek: Budownictwo Semestr: 1 (letni) Presentation of basic hydro and marine civil engineering structures together with basic computational procedures for determining environmental forces acting on a structure (vertical-wall breakwater, rubble mound breakwater, submarine pipelines...
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Hydro and marine civil engineering (2021-2022)
e-Learning CoursesKurs realizowany na Wydziale Inżynierii Lądowej i Środowiska (WILiŚ) Politechniki Gdańskiej. Studia: II stopnia - magisterskie, stacjonarne Kierunek: Budownictwo Semestr: 1 (letni) Presentation of basic hydro and marine civil engineering structures together with basic computational procedures for determining environmental forces acting on a structure (vertical-wall breakwater, rubble mound breakwater, submarine pipelines...
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Green TPUs from Prepolymer Mixtures Designed by Controlling the Chemical Structure of Flexible Segments
PublicationThis study concerns green thermoplastic polyurethanes (TPU) obtained by controlling the chemical structure of flexible segments. Two types of bio-based polyether polyols—poly(trimethylene glycol)s—with average molecular weights ca. 1000 and 2700 Da were used (PO3G1000 and PO3G2700, respectively). TPUs were prepared via a two-step method. Hard segments consisted of 4,4?- diphenylmethane diisocyanates and the bio-based 1,4-butanodiol...
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Superconducting properties of vn-sio 2 sol-gel derived thin films
Publicationin this work studies of structure and superconducting properties of vnsio2 films are reported. the films were obtained through thermal nitridation (ammonolysis) of solgel derived v2o3sio2 coatings (in a proper v2o3/sio2 ratio) at 1200 ◦c. this process leads to the formation of disordered structure with vn metallic grains dispersed in the insulating sio2 matrix. the structural transformations occurring in the lms as a result...
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Enhancement of PUR/PIR foam thermal stability after addition of Zostera marina biomass component investigated via thermal analysis and isoconversional kinetics
PublicationIn the present work, a thorough thermogravimetric (TG) analysis of bio-based polyurethane–polyisocyanurate (PUR–PIR) foams in both nitrogen and oxygen atmosphere is performed. A sustainable element of the foam is a biopolyol obtained via acid-catalyzed liquefaction of Zostera marina and Enteromorpha Algae biomass. Based on isoconversional analysis and apparent activation energies, several conclusions are obtained. In contradiction...
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Green thermoplastic poly(ether-urethane)s – synthesis, chemical structure and selected properties investigation
PublicationThis work aimed to characterize the effect of the monomers chemical structure on the selected properties of the green thermoplastic poly(ether-urethane)s. During synthesis two types of polyether biopolyols, 4,4′-diphenylmethane diisocyanate and bio-based 1,3-propanediol were employed. Materials were synthesized with the use of two step method and two different prepolymers, which were mixed together in equimolar quantities. Obtained...
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Sustainable urban planning in the context of studentification of the inner city areas
PublicationThe social dimension of urban planning as well as the importance of local communities and civic participation are often underlined in contemporary urban renewal and revitalisation programmes based on the principles of sustainable development. British Urban Renaissance is one the most far-reaching and widely discussed urban regeneration strategies which aims at repopulation and social diversification of inner city areas and land...
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Properties of Composite Oxide Layers on The Ti13Nb13Zr Alloy
PublicationThe development of composite oxide layers on the Ti13Nb13Zr alloy, their structure and properties have been demonstrated. Two subsequent methods were applied to prepare the composite layers. During the first stage gas oxidation produced a solid oxide layer, and subsequently oxide nanotubes were produced by using an electrochemical method. Scanning electron microscopy (SEM), chemical analysis, energy dispersive X-ray spectroscopy...
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Local material symmetry group for first- and second-order strain gradient fluids
PublicationUsing an unified approach based on the local material symmetry group introduced for general first- and second-order strain gradient elastic media, we analyze the constitutive equations of strain gradient fluids. For the strain gradient medium there exists a strain energy density dependent on first- and higher-order gradients of placement vector, whereas for fluids a strain energy depends on a current mass density and its gradients....
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Safety assessment of a concrete viaduct damaged by vehicle impact and an evaluation of the repair
PublicationDamage to lower parts of viaducts caused by impact from under-passing high vehicles is relatively frequent. One such incident, in which a viaduct was damaged by the impact from a truck with an improperly assembled hydraulic crane, is considered in this work. The analysis is based on a detailed object damage evaluation, 3D laser scanning, and numerical simulations. The aim of the study is to accurately model the vehicle impact into...
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Synthesis, structure and physical properties of new intermetallic spin glass-like compounds RE2PdGe3 (RE = Tb and Dy)
PublicationNew intermetallic compounds Tb2Pd1.25Ge2.75 and Dy2Pd1.25Ge2.75 have been synthesized using the arc-melting method. The crystallographic structure and magnetic, electronic transport, and thermal properties are reported. The crystal structure obtained from powder x-ray diffraction analysis suggests that these compounds crystallize in the AlB2-type structure (space group P6/mmm, no. 191) with lattice parameters a = 4.228 53(5)/4.230 54...
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Elastic polyurethane foams containing graphene nanoplatelets
PublicationElastic polyurethane foams were produced from two-component polyurethane systems (SPECFLEX NE 113 izocyjanian/NR 816 poliol system—SPC and Elastic MBMarket company system POLYOL ET MB 500/ISO ET MB 800—ET) by using a one-step method. The foams were a graphene nanoplatelets (GNP) in the amount ranging from 1 to 2 wt.%. The effect of the nanofiller on polyurethane matrix was determined by analyzing the chemical structure, static...
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The study on application of biopolyols obtained by cellulose biomass liquefaction performed with crude glycerol for the synthesis of rigid polyurethane foams
PublicationIn this work rigid polyurethane foams (PUR) were obtained by replacement of 0–70 wt% of petrochemical polyol with bio-polyol obtained via cellulose liquefaction in presence of crude glycerol. The foams with different content of a bio-polyol were prepared by single step method for NCO/OH ratio equals 1.5. The prepared materials were analyzed in terms of their morphology, chemical structure, thermal stability and basic physical and...
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Analysis of EN 1993-1-6 guidelines about determining amplitudes of equivalent imperfections of steel cylindrical shells subjected to uniform external pressure
PublicationCivil engineering structures should be designed with reference to relevant standards. One of them is a Eurocode 3 standard EN 1993-1-6:2007: Design of steel structures Part 1-6: Strength and Stability of Shell Structures. According to this standard, the value of buckling load can be determined using different approaches: classical hand calculations (stress design) and geometrical and material non-linear analysis of an imperfect...
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KOMPOZYTOWY MOST PIESZO - ROWEROWY
PublicationPaper presents the composite foot and cycle bridge developed in FOBRIDGE grant cofinanced by The National Centre for Research and Development and realized by consortium of Gdansk University of Technology (leader), Military University of Technology in Warsaw and ROMA Sp. z o.o. in Toruń. The purpose of the grant was to design a shell type single span foot and cycle bridge made of composite materials, with the assumption of manufacturing...
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Chitin nanowhiskers from shrimp shell waste as green filler in acrylonitrile-butadiene rubber: Processing and performance properties
PublicationIn this work, chitin nanowhiskers with high crystallinity index were obtained from shrimp shells waste using acid hydrolysis method and then comprehensively characterized. Subsequently, the impact of chitin nanowhisker content on processing and performance of acrylonitrile-butadiene rubber based nanocomposites was evaluated. The results showed that the addition of chitin nanowhiskers increased tensile strength and tear strength...
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Low-Cost Open-Hardware System for Measurements of Antenna Far-Field Characteristics in Non-Anechoic Environments
PublicationExperimental validation belongs to the most important steps in the development of antenna structures. Measurements are normally performed in expensive, dedicated facilities such as anechoic chambers, or open-test sites. A high cost of their construction might not be justified when the main goal of antenna verification boils down to demonstration of the measurement procedure, or rough validation of the simulation models used for...
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COMPOSITE FOOTBRIDGE - SYNERGY EFFECT IN COOPERATION BETWEEN UNIVERSITIES AND INDUSTRY
PublicationPaper presents conditions of science and industry cooperation in Poland (restrictions, barriers, good practice). A key role in initiation of collaboration between units has financial support. What is also important, it is much easier to create innovative solutions on the base of combining the potential of individuals. That is why many countries all over the world look for innovative solutions using budget funds to support grants...
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Polyurethane-based aerogels: Preparation, properties, and applications
PublicationPolyurethane aerogels (PUAs) are interesting materials because of their high porosity, low density, and low thermal conductivity, which result in their application as thermal insulations. PUAs are mainly synthesized using di- and polyisocyanates, diols or polyols, catalysts (tertiary amines and organometallic), and solvents (which are used as reaction medium, purifying of obtained semiproducts). Preparation procedure involves several...
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Effect of sisal fiber filler on thermal properties of bio-based polyurethane composites
PublicationThis work is mainly focused on study of thermal and thermomechanical properties of obtained bio-based polyurethane (coded as bio-PU) composites via using different types of bio-components (bio-glycol, modified soybean oil and sisal fiber) in the procedure. The chemical structure, morphology and mechanical properties were also investigated and described in this manuscript in order to know more perfect characterization of produced...
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The effect of hybridization of fire retarded epoxy/flax-cotton fiber laminates by expanded vermiculite: Structure-property relationship study
PublicationThe study describes the hybridization of epoxy/flax-cotton (EP/FF) composites containing ammonium polyphosphate (APP) with micrometric expanded vermiculite (VMT) (1–10 wt%). The efficiency of hybridization of flame retarded epoxy/flax-cotton composites was assessed by performing static tensile and flexural strength evaluation, supplemented by impact strength measurements of the composites. Moreover, thermal and thermomechanical...
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Experimental Study of Dapped-End Beams Subjected to Inclined Load
PublicationThis paper presents the results of an experimental investigation of the reinforced concrete (RC) dapped-end beams loaded with inclined forces, compared to identical ones loaded with vertical forces only. Such a load may occur in, for example, Gerber's joints or in dapped-end beams supported on corbels, where the vertical gravitation force is additionally completed with horizontal forces caused by temperature differences, shrinking,...
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Microemulsion Delivery Systems with Low Surfactant Concentrations: Optimization of Structure and Properties by Glycol Cosurfactants
PublicationExtensive use of microemulsions as delivery systems raises interest in the safe ingredients that can form such systems. Here, we assessed the use of two glycols, i.e., propylene glycol and pentylene glycol, and their mixtures to manipulate the properties and structure of microemulsions. Obtained systems with glycols were extensively characterized in terms of capacity to incorporate water phase, droplet size, polydispersity, structure...
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Poroelastic Low Noise Road Surfaces
PublicationNoise is one of the most important problems related to road traffic. During the last decades, noise emitted by engine and powertrain of vehicles was greatly reduced and tyres became a clearly dominant noise source. The paper describes the concept of low noise poroelastic road surfaces that are composed with mineral and rubber aggregate bound by polyurethane resin. Those surfaces have a porous structure and are much more flexible...
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Diagnostics and monitoring of the longest span extradosed bridge in Europe
PublicationThe article presents complex diagnostic procedures applied for the purpose of behavior analysis of the extradosed bridge with the longest span in Europe that was built in 2018 in Poland. The system of health monitoring was used to: register internal forces in temporary supports, monitor concrete bonding, perform in situ diagnostics and operation tests. The bridge is a continuous four-span structure with spans theoretical lengths...
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Ultra Low Noise Poroelastic Road Surfaces
PublicationNoise is one of the most important environmental problems related to road traffic. During the last decades, the noise emitted by the engines and powertrains of vehicles was greatly reduced and tires became a clearly dominant noise source. The article describes the concept of low noise poroelastic road surfaces that are composed of mineral and rubber aggregate bound by polyurethane resin. Those surfaces have a porous structure and...
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Hydration of Oxometallate Ions in Aqueous Solution
PublicationThe strength of hydrogen bonding to and structure of hydrated oxometallate ions in aqueous solution have been studied by double difference infrared (DDIR) spectroscopy and large-angle X-ray scattering (LAXS), respectively. Anions are hydrated by accepting hydrogen bonds from the hydrating water molecules. The oxygen atom of the permanganate and perrhenate ions form weaker and longer hydrogen bonds to water than the hydrogen bonds...
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Optimized Computational Intelligence Model for Estimating the Flexural Behavior of Composite Shear Walls
PublicationThis article presents a novel approach to estimate the flexural capacity of reinforced concrete-filled composite plate shear walls using an optimized computational intelligence model. The proposed model was developed and validated based on 47 laboratory data points and the Transit Search (TS) optimization algorithm. Using 80% of the experimental dataset, the optimized model was selected by determining the unknown coefficients of...
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Joints Of Steel Sandwich Structures
PublicationSteel sandwich structures are perceived as alternatives to single-skin welded structures in the shipbuilding industry due its advantages like significant reduction of mass in relation to typical single skin structure. However, beside problems with their strength properties itself, applications in real structures requires of solving the problem of joining, both for connection sandwich to sandwich as well as sandwiches to single-shell...
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Numerical modeling and experimental validation of full-scale segment to support design of novel GFRP footbridge
PublicationThe paper contains analysis of full-scaled three meters long segment of a novel composite footbridge. Both numerical modeling and experimental validation were performed. Analyzed object is a shell type sandwich channel-like structure made of composite sandwich with GFRP laminates as a skin and PET foam as a core. Several static load schemes were performed including vertical and horizontal forces. In FEM analysis multilayered laminate...
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Assessment of microstructure, physical and thermal properties of bitumen modified with LDPE/GTR/elastomer ternary blends
PublicationLDPE/GTR/elastomer ternary blends with variable LDPE/GTR ratio and constant elastomer content were prepared via melt-compounding. Obtained LDPE/GTR/elastomer blends were applied as thermoplastic modifiers into bitumen. Microstructure, physical and thermal properties of the modified bitumen were determined. It was observed that chemical composition of LDPE/GTR/elastomer blends has significant influence on their density and rheological...
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Modification of thermal and rheological characteristics of bitumen by waste PET/GTR blends
PublicationWaste poly(ethylene terephthalate) (wPET)/ground tire rubber (GTR) blends with variable compositions were applied as low-cost modifiers into bitumen and their performance has been evaluated via morphological, thermal and rheological analyses. Depending on the weight ratio of wPET/GTR, dispersion of single/composite domains of waste polymers in the bitumen has promoted the interaction between bitumen and blend components. Fourier...
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STRUCTURE AND MAGNETIC PROPERTIES OF Bi5Ti3FeO15 CERAMICS PREPARED BY SINTERING, MECHANICAL ACTIVATION AND EDAMM PROCESS. A COMPARATIVE STUDY
PublicationThree different methods were used to obtain Bi5Ti3FeO15 ceramics, i.e. solid-state sintering, mechanical activation (MA) with subsequent thermal treatment, and electrical discharge assisted mechanical milling (EDAMM). The structure and magnetic properties of produced Bi5Ti3FeO15 samples were characterized using X-ray diffraction and Mössbauer spectroscopy. The purest Bi5Ti3FeO15 ceramics was obtained by standard solid-state sintering...
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Chromium Cluster Luminescence: Advancing Near‐Infrared Light‐Emitting Diode Design for Next‐Generation Broadband Compact Light Sources
Open Research DataIn modern technology devices, an energy-saving miniature near-infrared (NIR) light source plays a critical role in non-destructive, non-invasive sensing applications and further advancement of technology. This dataset reports the broadband NIR luminescence of Cr3+ clusters for designing phosphor-converted NIR light-emitting diodes as an alternative...
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Thermographic imaging of electrochemical double layer capacitors during cycling charging - discharging 0 - 2,75 V at 241 mA. Sample 24, run #3.
Open Research DataDataset contains thermal images of prototype electrochemical double layer capacitor taken during cyclic charging - discharging. The sample was charged to 2,75 V and discharged to 10 mV by constant current 241 mA, experiment run #3The images were taken with thermographic camera VigoCAM V50. The sample was covered by black graphite paint to ensure uniform...
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Thermographic imaging of electrochemical double layer capacitors during cycling charging - discharging 0 - 2,75 V at 241 mA. Sample 24, run #5.
Open Research DataDataset contains thermal images of prototype electrochemical double layer capacitor taken during cyclic charging - discharging. The sample was charged to 2,75 V and discharged to 10 mV by constant current 241 mA, experiment run #5.The images were taken with thermographic camera VigoCAM V50. The sample was covered by black graphite paint to ensure uniform...
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Thermographic imaging of electrochemical double layer capacitors during cycling charging - discharging 0 - 2,8 V at 241 mA. Sample 24, run #1.
Open Research DataDataset contains thermal images of prototype electrochemical double layer capacitor taken during cyclic charging - discharging. The sample was charged to 2,8 V and discharged to 10 mV by constant current 241 mA, experiment run #1.The images were taken with thermographic camera VigoCAM V50. The sample was covered by black graphite paint to ensure uniform...
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Thermographic imaging of electrochemical double layer capacitors during cycling charging - discharging 0 - 3,0 V at 250 mA. Sample 24.
Open Research DataDataset contains thermal images of prototype electrochemical double layer capacitor taken during cyclic charging - discharging. The sample was charged to 3,0 V and discharged to 10 mV by constant current 250 mA. Last experiment with sample 24The images were taken with thermographic camera VigoCAM V50. The sample was covered by black graphite paint to...
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Thermographic imaging of electrochemical double layer capacitors during cycling charging - discharging 0 - 2,5 V at 180 mA. Sample 24
Open Research DataDataset contains thermal images of prototype electrochemical double layer capacitor taken during cyclic charging - discharging. The sample was charged to 2,5 V and discharged to 10 mV by constant current 180 mA. The images were taken with thermographic camera VigoCAM V50. The sample was covered by black graphite paint to ensure uniform surface emission....
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Thermographic imaging of electrochemical double layer capacitors during cycling charging - discharging 0 - 2,7 V at 80 mA. Sample 41.
Open Research DataDataset contains thermal images of prototype electrochemical double layer capacitor taken during cyclic charging - discharging. The sample was charged to 2,7 V and discharged to 10 mV by constant current 80 mA. Sample 41.The images were taken with thermographic camera VigoCAM V50. The sample was covered by black graphite paint to ensure uniform surface...
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Thermographic imaging of electrochemical double layer capacitors during cycling charging - discharging 0 - 2,75 V at 241 mA. Sample 24, run #2.
Open Research DataDataset contains thermal images of prototype electrochemical double layer capacitor taken during cyclic charging - discharging. The sample was charged to 2,75 V and discharged to 10 mV by constant current 241 mA, experiment run #2The images were taken with thermographic camera VigoCAM V50. The sample was covered by black graphite paint to ensure uniform...