Search results for: WASTE PLASTIC STRAWS
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Fracture prediction in flat PMMA notched specimens under tension - effectiveness of the equivalent material concept and fictitious material concept
PublicationThe fracture of notched elements under mode I loading (tension) remains an inexhaustible research topic, especially when it comes to the fracture of thermoplastic materials such as polymethylmethacrylate (PMMA), which experience considerable plastic strains under tension. The paper points out that traditional brittle fracture criteria such as mean stress (MS) or maximum tangential stress (MTS) criteria used to predict this phenomenon do...
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Contemporary Architectural Design in the Context of Historic Remains: The Case of the Old City of Gdańsk
PublicationThis article presents several examples of modern developments designed to preserve and coexist with fragments of historic brick buildings. These building projects each faced a similar task; to save and display the historical urban fabric, but they differed significantly in how they chose to achieve that goal. Not all of the projects presented in this study meet the requirements of the Venice Charter equally well. In this field,...
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Miniaturization of ESPAR Antenna Using Low-Cost 3D Printing Process
PublicationIn this paper, the miniaturized electronically steerable parasitic array radiator (ESPAR) antenna is presented. The size reduction was obtained by embedding its active and passive elements in polylactic acid (PLA) plastic material commonly used in low-cost 3D printing. The influence of 3D printing process imperfections on the ESPAR antenna design is investigated and a simple yet effective method to compensate them has been proposed....
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Compatibilization of polymeric composition filled with ground tire rubber – short review
PublicationWaste rubber is recognized as valuable materials resource and searching for new recycling methods is the main activity of many research institutions and companies. At the turn of the last years only few scientific papers about foamed polymer compositions filled with ground tire rubber were published. In paper review about progress in compatibilization and foaming of polymeric compositions filled with ground tire rubber.
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Przepustowość przepustu niezatopionego
PublicationPodczas przepływu w warunkach niezatopionego wlotu i wylotu w przewodzie przepustu woda tworzyć będzie swobodne zwierciadło. Przepływ bezciśnieniowy w przewodzie przepustu może wystąpić również w warunkach zatopionego wlotu. W pracy porównano wyniki obliczeń przepustowości całego przepustu i samego przewodu o przekroju kołowym i kwadratowym. W warunkach spokojnego ruchu wody, przy braku spiętrzenia na wylocie, o przepustowości...
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Determination of Selected Organic Acids in Animal Farm Water Samples by Ion Chromatography
PublicationLow molecular mass carboxylic acids (LCAs) occur in many environmental compartments due to natural processes and human activity. They are an important group of organic pollutants of waste water that mainly includes, volatile fatty acids, and also dicarboxylic, aromatic, hydroxy- and ketoacids. LCAs are present in the environment at concentrations between 1 to 5000 ppm and different methods have been reported for their determination...
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BIOGAS PRODUCTION FROM BAKERY WASTES -DYNAMICS, RETENTION TIME AND BIOGAS POTENTIAL
PublicationThis paper presents results of bakery-waste methane-fermentation. The scope of the study covers the determination of basic physicochemical parameters, process dynamics and retention time as well as biogas composition and biogas efficiency. Methane fermentation process was carried out in accordance with German Standard DIN 38414 S8 and under condition of 38°C. Conclusion: bakery wastes have big potential for biogas production.
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Ocena sprawności cyklu roboczego Pojazdu do Usuwania Odpadów z Pojemników na podstawie danych eksploatacyjnych
PublicationW artykule przedstawiona została metoda oceny sprawności cyklu roboczego śmieciarki. Wykorzystując dane eksploatacyjne wyznaczono dwa reprezentatywne cykle i na ich podstawie obliczono zarówno sprawność całego cyklu, jak i jego poszczególnych faz. Porównano wartości energii potrzebnej do opróżniania pojemników, energii do zagęszczania odpadów oraz energii z paliwa. Przedstawiono przebiegi mierzonych i obliczonych wartości w czasie...
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Technological solutions to landfill management: Towards recovery of biomethane and carbon neutrality
PublicationInadequate landfill management poses risks to the environment and human health, necessitating action. Poorly designed and operated landfills release harmful gases, contaminate water, and deplete resources. Aligning landfill management with the Sustainable Development Goals (SDGs) reveals its crucial role in achieving various targets. Urgent transformation of landfill practices is necessary to address challenges like climate change,...
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The Staged Combustion of Meat-and-Bone Meal:The Characteristics of Conversion Sub-processes and Large-Scale Process Outputs
Publicationt Organic waste has been playing an increasingly important role in the energy market as those that may support the economies in pursuing towards decarbonization by increasing the share of renewables in the overall energy balance. In this group of alternative fuels, meat-and-bone meals being a post-production waste of the steadily developing meat industry, constitute a considerable proportion. Though they are rich in minerals, their...
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Future opportunities for products derived from black soldier fly (BSF) treatment as animal feed and fertilizer - A systematic review
PublicationThe pursuit of novel food products with good nutritional value for both direct and indirect human consumption is crucial. Given the nutritional benefits of insects and the sustainability of this sort of farming, using them as food for farmed animals is a promising alternative. In this regard, the black soldier fly (Hermetia illucens) is most capable of efficiently converting a wide variety of organic materials, from food waste...
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Synthesis and Physicochemical Characteristics of Chitosan-Based Polyurethane Flexible Foams
PublicationThe use of shrimp waste to obtain chitosan (Ch) is an essential issue, considering a circular economy, waste management, and its application to environmentally friendly materials. In this study, northern prawn shells were utilized to obtain Ch, which could then be used for synthesizing chitosan-based polyurethane (PUR+Ch) foams with different Ch concentration. The chemical structure, morphology, hardness, thermal properties, viscoelastic...
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Influence of the fragment size on the recycling process of thin-film modules based on CdTe
PublicationFor several years, the production of second generation cells (the so-called thin film), produced from amorphous silicon, cadmium telluride (CdTe) or copper indium (gallium) diselenide (CI(G)S), has been increasing. The total number of end-of-life panels by 2050 is expected to reach 9.57 million tonnes. They contain heavy metals that can be leached into the environment at the land field. The EU directive on waste electrical and...
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Structural Changes and Their Implications in Foamed Flexible Polyurethane Composites Filled with Rapeseed Oil-Treated Ground Tire Rubber
PublicationThe utilization of post-consumer car tires is an essential issue from an ecological andeconomic point of view. One of the simplest and the least harmful methods is their material recyclingresulting in ground tire rubber (GTR), which can be further applied as fillers for polymer-basedcomposites. Nevertheless, insufficient interfacial interactions implicate the necessity of GTR modi-fication before introduction into polymer matrices....
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Application of Thermo-chemical Technologies for Conversion of Associated Gas in Diesel-Gas Turbine Installations for Oil and Gas Floating Units
PublicationThe paper considers the issue of thermo-chemical recovery of engine’s waste heat and its further use for steam conversion of the associated gas for oil and gas floating units. The characteristics of the associated gas are presented, and problems of its application in dual-fuel medium-speed internal combustion engines are discussed. Various variants of combined diesel-gas turbine power plant with thermo-chemical heat recovery are...
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Nieliniowa statyka 6-parametrowych powłok sprężysto plastycznych. Efektywne obliczenia MES
PublicationGłównym zagadnieniem omawianym w monografii jest sformułowanie sprężysto-plastycznego prawa konstytutywnego w nieliniowej 6-parametrowej teorii powłok. Wyróżnikiem tej teorii jest występujący w niej w naturalny sposób tzw. stopień 6 swobody, czyli owinięcie (drilling rotation). Podstawowe założenie pracy to przyjęcie płaskiego stanu naprężenia uogólnionego na ośrodek typu Cosseratów. Takie podejście stanowi oryginalny aspekt opracowania....
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High-temperature heat pumps – new devices for heat recovery and production of technological steam
PublicationIn the paper, the original high temperature compressor based heat pump with a dry working fluid, i.e. the one in which the slope of saturated vapour line is positive, was presented. The objective of the paper is to investigate the possibility of preparation of technological steam with tempperature 120 C from the waste heat resource at temperature of 50 C. Single comppression cycles as well as cascade systems have been considered...
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A new construction of shell-and-tube heat exchanger with impinging jets and minichannels technologies for heat recovery from gases – experimental analysis
PublicationA dynamic development of technologies allowing waste heat utilization is observed in a correspondence with a pro-ecological approach of the zero waste idea. Such approach becomes the most demanding in the area of low-temperature was heat sources, especially gaseous media. Till now, they were usually not utilized due to unfavorable thermal conditions and high costs. Therefore, the zero waste approach directs research on techniques...
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Propagation of acoustic pulses in some fluids with yield stress
PublicationThis study is devoted to the derivation of approximate equations governing acoustic pulses in flows with yieldstress, including some time-dependent flows with a slow dependence on time of yield stress and apparent viscosity. Themodeling of yield stress and apparent viscosity in the vicinity of a zero deformation rate allows us to consider a thixotropicfluid as a Bingham plastic with coefficients that are dependent on time. The...
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Three phase transient model of wet coal pyrolysis
PublicationA one-dimensional transient mathematical model was developed to describe the thermal and flow phenomena during coal pyrolysis in a coke oven. The model was solved numerically using partly implicit methods for gas flow and heat transfer problems. It was successfully validated with industrial-scale measurements of temperature change in the middle-plane of the coke oven chamber. The evolution of temperature and pressure, distributions...
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Composite GFRP U-shaped footbridge
PublicationThe paper presents proposals for the use of glass fiber reinforced polymer composites for the construction of engineering objects, known and commonly used in the shipbuilding industry. An example of a pedestrian footbridge was used in this case, which, despite the considerable thickness of the structural material, was made using infusion technology in one production cycle. The designed and produced footbridge span is durable, dynamically...
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CONCRETE MIX DESIGN USING ABRAMS AND BOLOMEY METHODS
PublicationOne way to reduce the consumption of cement is to optimize its use. Many known methods of concrete design, based on the Abrams law and the Bolomey method. Therefore, the authors chose those methods for analysis. The concrete composition with the assumed strength class, calculated by any method differs significantly. This applies especially to the cement content, as its content in the composition of concrete varies from 20 to 50%....
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ASSESSMENT OF VOLATILE ORGANIC COMPOUNDS EMISSIONS FROM RECYCLED LOW-DENSITY POLYETHYLENE STREAMS
PublicationThe recycling of plastics is currently one of the most significant industrial challenges. Due to the enormous amounts of plastic wastes generated by various industry branches, it is essential to look for the potential methods of their utilization. Nevertheless, it should not be forgotten that recycled plastics are not pure materials, and they still may show an unfavorable environmental impact. They may contain different contaminants...
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Performance of isotropic constitutive laws in simulating failure mechanisms in scaled RC beams
PublicationResults of numerical calculations of reinforced concrete (RC) beams are presented. Based on experimental results on longitudinally reinforced specimens of different sizes and shapes are investigated. Four different continuum constitutive laws with isotropic softening are used: one defined within continuum damage mechanics, an elasto-plastic with the Rankine criterion in tension and the Drucker-Prager criterion in compression, a...
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The influence of feed rate and shear forces on the devulcanization process of ground tire rubber (GTR) conducted in a co-rotating twin screw extruder
PublicationThe search for new ways to recycling of rubber waste has been the aim of many studies conducted by research centers and companiesworldwide. The results of our investigations on the process of continuous thermomechanical devulcanization of ground tire rubber using a twin screw extruder are presented.We used a co-rotating twin screw extruder with a special configuration of plasticizing unit, enabling generation of considerable shear...
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Distillery Fusel Oil as an Alternative Carbon Source for Denitrification – from Laboratory Experiments to Full-Scale Applications
PublicationIndustrial waste products may be a viable alternative to commercial external carbon sources, such as ethanol. In this study, the properties of fusel oil (distillery waste product) were investigated in terms of temperature dependency of denitrification, acclimation period, and the effects on NO2-N and PO4-P behavior. Furthermore, results obtained during three different full-scale trials were used to verify similarities and differences...
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Prediction of Bioactive Peptides From Chicken Feather and Pig Hair Keratins Using In Silico Analysis Based on Fragmentomic Approach
PublicationBackground: Keratin is among the most abundant structural proteins of animal origin, however it remains broadly underutilized. Objective: Bioinformatic investigation was performed to evaluate selected keratins originating from mass-produced waste products, i.e., chicken feathers and pig hair, as potential sources of bioactive peptides. Methods: Pepsin, trypsin, chymotrypsin, papain, and subtilisin were used for in silico keratinolysis...
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Partial inhibition of borohydride hydrolysis using porous activated carbon as an effective method to improve the electrocatalytic activity of the DBFC anode
PublicationCarbon materials are commonly used catalyst supports in various types of fuel cells. Due to the possibility of designing their properties, they seem to be attractive and functional additives. In Direct Borohydride Fuel Cells (DBFCs), the electrooxidation reaction of borohydride competes with the undesirable hydrolysis reaction, therefore our work aimed to modify anodes based on a multi-component hydrogen storage alloy with a small...
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Ground tire rubber functionalization as a promising approach for the production of sustainable adsorbents of environmental pollutants
PublicationWaste tires management and further utilization are currently one of the biggest concerns regarding the environment and human health protection. At present, shredding, grinding, or pulverization of waste tires are the most popular options for industrial recycling. Although many solutions for ground tire rubber (GTR) applications were checked and verified so far, their further implementation at an industrial scale is still very limited....
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Wybrane aspekty modelowania uderzenia pojazdem dźwigara wiaduktu
PublicationW pracy przedstawiono różne zagadnienia związane z uderzeniem pojazdu w dźwigar wiaduktu. Omówiono wybór modelu obliczeniowego, na podstawie porównania wyników dla modelu dźwigara zespolonego, modelu dźwigara stalowego oraz modelu wiaduktu. Następnie opisano model dźwigara zespolonego zastosowany w analizie MES oraz metodę wyznaczania współczynników tłumienia Rayleigha. Symulację numeryczną uderzenia dźwigara wiaduktu przez koparkę...
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Characteristic and specificity of protease activity of thermophilic bacteria Meiothermus ruber
PublicationThe primary purpose of research was to establish the possibility of using thermophilic bacteria Meiothermus ruber as a source of proteolytic enzymes. The main reason of searching new proteases is their commercial value especially in production of detergents, food, pharmaceuticals, leather, diagnostics or waste management. The development of this type processes will be possible by utilization of enzymes which have unique characteristics...
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FATE OF LAS SURFACT ANTS IN WWTPs BASED ON MEASURED CONCENTRATIONS IN WASTEWATER AND SLUDGE
PublicationThe fate of the surfactant LAS in the two different types of Waste Water Treatment Plants has been reviewed: the small “Swarzewo” WWTP (45 000 PE), and large WWTP “Wschód” (760 000 PE). The elimination of LAS from the water stream in Swarzewo (98,7%), is better than that found in Gdańsk (97,6%). In the sludge treatment course, the reduction of LAS in Swarzewo is greater than that in Gdańsk due to the greater biodegradation of LAS...
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Identification of pollutants at the adjacent areas to the landfill site using two dimensional gas chromatography with mass spectrometry technique
PublicationMunicipal landfills are considered one of the main sources of air pollutants. In this article is presented the use of a modern analytical technique: a two dimensional gas chromatography to identify the substances in the atmospheric air near a waste processing plant located in Gdansk. In order to determine the types of substances occurring in different atmospheric conditions, the study was conducted from February to April 2016....
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Photolysis for the Removal and Transformation of Pesticide Residues During Food Processing: A State-of-the-Art Minireview
PublicationPesticide residues are of great significant issue that exerted adverse effects on humans. There is a need for effective and non-toxic decontamination of pesticide residues during food processing. In this minireview, the recent advances in the degradation of pesticide residues by photolysis have been firstly described during food processing. The mechanisms of pesticide residues destruction by photolysis were discussed accordingly....
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Mechanical Recycling via Regrinding, Rebonding, Adhesive Pressing, and Molding
PublicationIncreasing amount of polyurethane foams waste (e.g. from the building or furniture industry) produced every year resulted in the intensive development of their recycling methods. This chapter covers most important mechanical recycling methods, i.e. regrinding, rebonding, adhesive pressing, and molding. The procedure, required equipment and chemicals (if needed) for each method were described. The possible applications of the products...
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A new strategy for PET depolymerization: Application of bimetallic MOF-74 as a selective catalyst
PublicationLarge-volume production of poly(ethylene terephthalate) (PET), especially in the form of bottles and food packaging containers, causes problems with polymer waste management. Waste PET could be recycled thermally, mechanically or chemically and the last method allows to obtain individual monomers, but most often it is carried out in the presence of homogeneous catalysts, that are difficult to separate and reuse. In view of this,...
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Sustainable Management of Food Wastes Through Cavitation-Assisted Conversion into Value-Added Products
PublicationMore than 30% of worldwide food consumption is thrown out as food wastes causing serious environmental, economic, and social problems. Therefore, it is required to develop sustainable food waste management methods leading to an enhancement in social and economic benefits and mitigation of environmental impacts. Anaerobic digestion can be regarded as one of those effective methods that can be employed for the conversion of food...
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Distillery Fusel Oil as an Alternative Carbon Source for Denitrification – from Laboratory Experiments to Full-Scale Applications
PublicationIndustrial waste products may be a viable alternative to commercial external carbon sources. In this study, the properties of fusel oil (distillery waste product) were investigated in terms of temperature dependency of denitrification and acclimation period. Furthermore, results obtained during three different full-scale trials were used to verify similarities and differences with the results obtained under laboratory-scale conditions....
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Comparative analysis of thermodynamic cycles of selected nuclear ship power plants with high-temperature helium-cooled nuclear reactor
PublicationThis paper presents a comparative analysis of thermodynamic cycles of two ship power plant systems with a high-temperature helium- cooled nuclear reactor. The first of them is a gas system with recuperator , in which classical gas chamber is substituted for a HTGR reactor (High Temperature Gas-cooled Reactor) . The second of the considered cycles is a combined gas-steam system where working medium flux from gas turbine outlet...
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Structure and performance properties of environmentally-friendly biocomposites based on poly(ɛ-caprolactone) modified with copper slag and shale drill cuttings wastes
PublicationThe potential application of two types of industrial wastes, drill cuttings (DC) and copper slag (CS), as silica-rich modifiers of poly(ɛ-caprolactone) (PCL) was investigated. Chemical structure and physical properties of DC and CS fillers were characterized using X-ray diffractometer, X-ray fluorescence spectroscopy, particle size and density measurements. PCL/DC and PCL/CS composites with a variable content of filler (5 to 50...
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Numeryczna symulacja pracy gazowego kotła wodnego oraz ocena jego wpływu na środowisko
PublicationIlość dostarczanego powietrza oraz rozkład jego koncentracji w komorze paleniskowej mają istotny wpływ na prawidłowość przebiegu procesu spalania. Uzyskanie jednorodnego rozkładu jest praktycznie niemożliwe, dlatego powietrze dostarczane jest w nadmiarze. Konieczne jest jednak dobranie takiej wartości współczynnika nadmiaru powietrza, która pozwoli ograniczyć stratę wylotową, utrzymując przy tym wartości emisji na możliwie niskim...
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"Numeryczna symulacja pracy gazowego kotła wodnego oraz ocena jego wpływu na środowisko"
PublicationIlość dostarczanego powietrza oraz rozkład jego koncentracji w komorze paleniskowej mają istotny wpływ na prawidłowość przebiegu procesu spalania. Uzyskanie jednorodnego rozkładu jest praktycznie niemożliwe, dlatego powietrze dostarczane jest w nadmiarze. Konieczne jest jednak dobranie takiej wartości współczynnika nadmiaru powietrza, która pozwoli ograniczyć stratę wylotową, utrzymując przy tym wartości emisji na możliwie niskim...
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"Numeryczna symulacja pracy gazowego kotła wodnego raz ocena jego wpływu na środowisko"
PublicationIlość dostarczanego powietrza oraz rozkład jego koncentracji w komorze paleniskowej mają istotny wpływ na prawidłowość przebiegu procesu spalania. Uzyskanie jednorodnego rozkładu jest praktycznie niemożliwe, dlatego powietrze dostarczane jest w nadmiarze. Konieczne jest jednak dobranie takiej wartości współczynnika nadmiaru powietrza, która pozwoli ograniczyć stratę wylotową, utrzymując przy tym wartości emisji na możliwie niskim...
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Kluczowe zagadnienia procesu recyklingu zużytych modułów fotowoltaicznych I i II generacji
PublicationW ramach technologii fotowoltaicznych wyróżniamy obecnie trzy generacje ogniw fotowoltaicznych. Pierwsza z nich to ogniwa z mono- i polikrystalicznego krzemu (c-Si), druga obejmuje ogniwa wykonane na bazie technologii cienkowarstwowej, zarówno z krzemu amorficznego (a-Si) jak i diseleneku indowo-miedziowo-galowego (CIGS), tellurku kadmu (CdTe) oraz arsenku galu (GaAs). Trzecia generacja to najnowsze technologie, takie jak: organiczne...
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Experimental study on steel columns subjected to impact load under earthquake conditions
PublicationEarthquakes affecting urbanized regions cause exceptional loads to load bearing structural elements such as columns. Such a boost in the load conditions can lead to severe damages which, in a worst case scenario, can lead to a total collapse of a building. This boost is caused by the horizontal ground movement generating a rise in the internal forces due to considerable large displacement between the top and bottom support of columns....
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The effect of elevated temperature on LCF damage growth in 2024AA – Experiment and modeling
PublicationThis paper presents the results of experimental low-cycle fatigue (LCF) tests conducted on EN-AW 2024 alloy in T3511 temper at 100 ◦C, 200 ◦C and 300 ◦C. The material’s basic fatigue characteristics were determined, such as fatigue life curve and cyclic strain curve. Both the hysteresis loop and nature of fracture surfaces obtained in macro- and microscopic observations (scanning electron microscope, SEM) were accounted for. The...
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LDFEM analysis of FDP auger installation in cohesive soil
PublicationThis paper deals with large deformation finite element (LDFE) preliminary modelling of Full Displacement Pile (FDP) installation in cohesive soil deposit located in Jazowa, Poland. The detailed FDP auger geometry is applied and the drilling process is modelled with full 3D Coupled Eulerian-Lagrangian (CEL) formulation. The total stress approach and elastic-perfectly plastic model with rate-dependent Mises plasticity is used. The...
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Deep Eutectic Solvents and Their Uses for Air Purification
PublicationChemical compounds released into the air by the activities of industrial plants and emitted from many other sources, including in households (paints, waxes, cosmetics, disinfectants, plastic (PVC) flooring), may affect the environment and human health. Thus, air purification is an important issue in the context of caring for the condition of the environment. Deep eutectic solvents (DESs) as liquids with environmentally friendly...
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Three-dimensional printed trachea helps to design tailored treatment for tracheobronchomalacia
PublicationTracheobronchomalacia is a rare respiratory disease that is manifesting by impaired ventilation with expiratory collapse of the tracheal wall due to softening of the supporting cartilage and hypotonia of myoelastic elements [1]. Surgery is the mainstay of treatment. We report the case of 39 -year old man with exacerbation of chronic respiratory distress. The membranous wall of the trachea and the large bronchi was stretched to...
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Experimental investigations and damage growth modeling of EN‐AW 2024 aluminum alloy under LCF loading accounting creep pre‐deformation
PublicationThis article presents the results of experimental tests of creep rupture and of low-cycle fatigue (LCF) of EN-AW 2024 aluminum alloy devoid of damage and having preliminary damage. The preliminary damage was dealt in the process of creep at elevated temperature 100C, 200C, and 300C until achievement of two different strain values at each temperature. Samples with preliminary damage were subjected to fatigue tests at room temperature....