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Nitrogen removal in two technologies of wastewater treatment
PublicationW pracy przedstawiono problematykę usuwania związków azotu ze ścieków w świetle wymogów prawnych Polski i Unii Europejskiej. Problem został scharakteryzowany w odniesieniu do dwóch typów oczyszczalni ścieków - pracujących w całkowicie różnych skalach: dużej oczyszczalni ścieków miejskich Gdańska (Oczyszczalnia ścieków ''Wschód'') oraz oczyszczalni hydrofitowych, przeznaczonych do oczyszczania względnie niewielkich objętości ścieków...
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Determination and pathways of nitrogen during wastewater treatment.
PublicationŚcieki rafineryjne, farmaceutyczne oraz z przemysłu spożywczego charakteryzują się wysoką zawartością azotu amonowego. Biologiczne oczyszczanie ścieków przemysłowych zazwyczaj stwarza poważne problemy technologiczne. Azot zawarty w tego typu ściekach jest zawarty w aminach, amidach, czyli związkach, które wymagają wstępnego oczyszczania w celu zmniejszenia ich stężenia do wartości nie inhibujących reakcji biochemicznych oraz nitryfikacji....
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Hydrothermal Surface Treatment of Biodegradable Mg-Materials
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Rheological, Mechanical, Microstructural and Radiation Shielding Properties of Cement Pastes Containing Magnetite (Fe3O4) Nanoparticles
PublicationThis 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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Studies on Silver Ions Releasing Processes and Mechanical Properties of Surface-Modified Titanium Alloy Implants
PublicationDispersed silver nanoparticles (AgNPs) on the surface of titanium alloy (Ti6Al4V) and titanium alloy modified by titania nanotube layer (Ti6Al4V/TNT) substrates were produced by the chemical vapor deposition method (CVD) using a novel precursor of the formula [Ag5(O2CC2F5)5(H2O)3]. The structure and volatile properties of this compound were determined using single crystal X-ray diffractometry, variable temperature IR spectrophotometry...
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Evaluating the effect of different operational strategies on the carbon footprint of wastewater treatment plants – case studies from northern Poland
PublicationNowadays, low greenhouse gas (GHG) emission is expected at wastewater treatment plants (WWTPs). However, emission quantification and evaluation still faces difficulties related to data availability and uncertainty. The objective of this study was to perform carbon footprint (CF) analysis for two municipal WWTPs located in northern Poland. Slupsk WWTP is a large biological nutrient removal (BNR) facility (250,000 PE) which benefits...
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Transcriptional profile of in vitro expanded human epidermal progenitor cells for the treatment of non-healing wounds
PublicationBackground Epidermal progenitor cells (EPCs) have been under extensive investigation due to their increasing potential of application in medicine and biotechnology. Cultured human EPCs are used in the treatment of chronic wounds and have recently became a target for gene therapy and toxicological studies. One of the challenges in EPCs culture is to provide a high number of undifferentiated, progenitor cells displaying high viability...
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Chitosan-coated coconut shell composite: A solution for treatment of Cr(III)-contaminated tannery wastewater
PublicationTannery industry generates a large amount of Cr(III)-contaminated wastewater daily. Unless properly treated, not only this effluent contaminates the water body, but also damages the environment and threatens public health. This batch study investigates the feasibility of chitosan-coated coconut shells as a low-cost material for removing Cr(III) from tannery wastewater. Both chitosan and coconut shell (CS) waste are abundantly available...
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Alternative treatment approaches of urinary tract infections caused by uropathogenic Escherichia coli strains
PublicationUrinary tract infections (UTIs) are the most widespread and annoying infections affecting millions of people every year annually. The biggest problem of urinary diseases are recurrences, the increasing resistance of uropathogens to commonly used antibiotics, as well as the high health care costs of afflicted persons. Uropathogenic Escherichia coli strains (UPECs) are the most dominant etiologic agent of community-acquired infections...
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Effect of Compounding Conditions on Static and Dynamic Mechanical Properties of High Density Polyethylene/Ground Tire Rubber Blends
PublicationSearching for new and cost-effective methods of waste rubber recycling is a subject of research in many scientific centers in the world. In this paper there are presented results of the research of the extrusion process of cheap and environmentally friendly thermoplastic compositions containing 50 % wt. of masses of ground tire rubber (GTR). The aim of this study was to determine the relationship between the mixing conditions and...
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Effect of slag coal ash and foamed glass on the mechanical properties of two-stage concrete
PublicationTwo-stage concrete (TSC) is known by various names such as colcrete, Polcrete, preplaced aggregate concrete and prepacked concrete. It is different from traditional concrete in two fundamental ways, namely method of construction and mix proportion. Two-stage concrete (TSC) is defined as firstly, coarse aggregates are placed into the formwork and grout is applied to fill in the between coarse aggregate particles voids. Secondly,...
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Innovations in Wastewater Treatment: Harnessing Mathematical Modeling and Computer Simulations with Cutting-Edge Technologies and Advanced Control Systems
PublicationThe wastewater treatment landscape in Central Europe, particularly in Poland, has undergone a profound transformation due to European Union (EU) integration. Fueled by EU funding and rapid technological advancements, wastewater treatment plants (WWTPs) have adopted cutting-edge control methods to adhere to EU Water Framework Directive mandates. WWTPs contend with complexities such as variable flow rates, temperature fluctuations,...
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Potential fertilizing properties of sewage sludge treated in the Sludge Treatment Reed Beds (STRB)
PublicationIn research the fertilizer value of sludge from reed beds is evaluated based on the sampling sludge on different depths from 4 Danish STRB after long periods of stabilization. The dewatering efficiency of sewage sludge in the STRB is comparable to mechanical dewatering. The long-term stabilization of sewage sludge progressively decreases the concentration of organic matter due to the process of humification. The aim of the work...
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Long-term operation of Kickuth-type constructed wetland applied to municipal wastewater treatment in temperate climate
PublicationThe purpose of this paper is to discuss the problem of changes of effectiveness of Kickuth-type constructed wetland with subsurface flow applied to domestic wastewater treatment. This study is based on an example of a wetland 3000 m2 in surface, serving 800 inhabitants, located in Poland. The results of chemical analysis showed that after an initial year of ‘start-up time’, the efficiency of pollutant removal gradually increased...
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Dynamic mechanical properties and flexing fatigue resistance of tire sidewall rubber as function of waste tire rubber reclaiming degree
PublicationA stepwise downsizing method of gel particles in reclaimed rubber to a micro-nano scale and its excellent dynamic performance in tire sidewall were introduced by this work. The results showed that the size of gel particles decreased from several micrometers to micro-nanometers with the increase of reclaiming degree, accompanied by reduced molecular weight and widened molecular weight distribution of sol fraction. The addition of...
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A distillery by-product as an external carbon source for enhancing denitrification in mainstream and sidestream treatment processes
PublicationThe use of fusel oil as an 'alternative' carbon source for denitrification in the mainstream and sidestream treatment processes was studied. Research comprised two kinds of batch experiments as well as acclimation of process biomass to external carbon sources. In the conventional nitrate utilization rate (NUR) measurements (one-phase experiments with non-acclimated biomass), the NUR with fusel oil was 1.4-1.7 g N/(kg VSS•h which...
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Nitrogen removal via the nitrite pathway during wastewater co-treatment with ammonia-rich landfill leachates in a sequencing batch reactor
PublicationThe biological treatment of ammonia-rich landfill leachates due to an inadequate C to N ratio requires expensive supplementation of carbon from an external carbon source. In an effort to reduce treatment costs, the objective of the study was to determine the feasibility of nitrogen removal via the nitrite pathway during landfill leachate co-treatment with municipal wastewater. Initially, the laboratory-scale sequencing batch reactor...
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Energy consumption optimization in wastewater treatment plants: Machine learning for monitoring incineration of sewage sludge
PublicationBiomass management in terms of energy consumption optimization has become a recent challenge for developed countries. Nevertheless, the multiplicity of materials and operating parameters controlling energy consumption in wastewater treatment plants necessitates the need for sophisticated well-organized disciplines in order to minimize energy consumption and dissipation. Sewage sludge (SS) disposal management is the key stage of...
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Physico‐Mechanical Properties and Flammability of PUR/PIR Foams Containing Expandable Graphite Core‐Shell Composite Particles
PublicationIn this work, polyurethane/polyisocyanurate (PUR/PIR) foams were modified by two types of expandable graphite (EG) core-shell composite particles. The pulverized EG core-shell composite particles were prepared during emulsion polymerization using methyl methacrylate or glycidyl methacrylate for the synthesis of the polymeric shells (poly(methyl methacrylate) (PMMA) and poly (glycidyl methacrylate) (PGMA)), and then the obtained EG_PMMA...
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Low-energy positron scattering from gas-phase tetrahydrofuran: A quantum treatment of the dynamics and a comparison with experiments
PublicationIn this paper we report new quantum calculations of the dynamics for low-energy positrons interacting with gaseous molecules of tetrahydrofuran. The new quantum scattering cross sections are differential and integral cross sections at collision energies between 1.0 and 25.0 eV and include a careful treatment of the additional effects on the scattering process brought about by the permanent dipole moment of the target molecule....
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Microstructure and Mechanical Properties of Combined GTAW and SMAW Dissimilar Welded Joints between Inconel 718 and 304L Austenitic Stainless Steel
PublicationA dissimilar welded joint of Inconel 718 and 304L austenitic stainless steel was prepared using a combined procedure with the gas tungsten arc welding and shielded metal arc welding processes by employing the Ni-based fillers: ERNiCr-3 and ENiCrFe-3. The welded joints were investigated for metallographic testing and mechanical properties, and a relationship was established between the microstructure and the resultant mechanical...
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Dynamic Properties of Two-Axle Freight Wagon with UIC Double-Link Suspension as a Non-smooth System with Dry Friction
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Friction and wear behaviour of self mated DLC and DLC-W coatings in water or salt in water solution lubricated sliding
PublicationPrzedstawiono wyniki badań powłok ceramicznych DLC oraz DLC z wolframem (DLC-W) nałożonych na podłoże ze stali nierdzewnej,przy tarciu ślizgowym , w modelowym skojarzeniu o styku konforemnym (płaskie czoło obracającej się względem swojej osi tulei - powierzchnia płaska). Badania prowadzono stosując smarowanie wodą destylowaną albo wodnym roztworem soli - NaCl. Wyznaczano współczynniki tarcia oraz intensywność zużywania ceramicznej...
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Friction and flow around growing tissue in bioreactor. Proceedings of the Biomechanics 2003. Engineering Biomechanics - Biomechanics of Sport - Medical Biomechanics.
PublicationPrzedstawione zostały problemy teoretyczne związane z wyznaczaniem sił tarcia, współczynników tarcia, rozkładów wartości ciśnienia w warstwie przyściennej wytworzonej wokół hodowanej tkanki w bioreaktorze w trakcie opływu tej tkanki cieczami biologicznymi o właściwościach lepkosprężystych. Model Rivlina Ericksena lepkosprężystej cieczy biologicznej jest tu brany pod uwagę.
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Morphology, Thermo-Mechanical Properties and Biodegradibility of PCL/PLA Blends Reactively Compatibilized by Different Organic Peroxides
PublicationReactive blending is a promising approach for the sustainable development of bio-based polymer blends and composites, which currently is gaining more and more attention. In this paper, biodegradable blends based on poly(ε-caprolactone) (PCL) and poly(lactic acid) (PLA) were prepared via reactive blending performed in an internal mixer. The PCL and PLA content varied in a ratio of 70/30 and 55/45. Reactive modification of PCL/PLA...
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Monitoring of crosslinking of a DGEBA-PAMAM adhesive in composite/aluminium bonded joint using mechanical and ultra-sound techniques
PublicationAdhesive cure is an important and determining aspect of strength and stability of bonded structures. Crosslinking of the polymer leads to the adhesive strength, stiffness and durability. Depending on the resin and curing agent used, cure time can vary from minutes to weeks, even then 100% crosslinking not being guaranteed. Standard methods based on dynamic mechanical analysis (DMA) or calorimetric techniques (DSC, DTA) are valuable...
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Evaluation of Health Hazard Due to Emission of Volatile Organic Compounds from Various Processing Units of Wastewater Treatment Plant
PublicationThe paper describes an attempt at health risk assessment and odour concentration determination in the most important units of a wastewater treatment plant. The cancer risk (CR) and hazard index (HI) parameters in selected measurement locations were calculated based on the results of chromatographic analyses (GCxGC-TOF-MS) and the United States Environmental Protection Agency (US EPA) guidelines. No exceedance of the CR and HI acceptable...
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Automotive fleet repair facility wastewater treatment using air/ZVI and air/ZVI/H2 O2 processes
PublicationAdvanced automotive fl eet repair facility wastewater treatment was investigated with Zero-Valent Iron/Hydrogen Peroxide (Air/ZVI/H2 O2 ) process for different process parameters: ZVI and H2 O2 doses, time, pH. The highest Chemical Oxygen Demand (COD) removal effi ciency, 76%, was achieved for ZVI/H2 O2 doses 4000/1900 mg/L, 120 min process time, pH 3.0. COD decreased from 933 to 227 mg/L. In optimal process conditions odor and...
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Enhanced electrochemical activity of boron-doped nanocarbon functionalized reticulated vitreous carbon structures for water treatment applications
PublicationAn extraordinary charge transfer kinetics and chemical stability make a boron-doped diamond (BDD) a prom- ising material for electrochemical applications including wastewater treatment. Yet, with flat geometrical sur- faces its scaling options are limited. In this study, the reticulated Vitreous Carbon (RVC) served as a substrate for boron-doped diamondized nanocarbons (BDNC) film growth resulting with complex heterogeneity carbon structures...
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Exploring synergistic effects in physical-chemical activation of Acorus calamus for water treatment solutions
PublicationThe research proposed a novel method of obtaining sorption material from readily available Acorus calamus bio- mass through a combination of physical and chemical activation processes. The material with the highest specific surface area (1652 m2 g−1) was obtained by physical activation with CO2, followed by chemical activation with KOH. Reversing the order of activation methods resulted in a lower specific surface area (1014 m2...
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Quantitative determination of mechanical stability in the novel coronavirus spike protein
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Thermal, Mechanical, and Morphological Properties of DPU/Titanate Nanotubes Nanocomposites
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The Influence of Nano-Fe3O4 on the Microstructure and Mechanical Properties of Cementitious Composites
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The Effect of Nanosilica on the Mechanical Properties of polymer-Cement Composites (PCC)
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Mechanical Modelling of Human Fascia in the Problem of Ventral Hernia Repair
PublicationPraca dotyczy badań doświadczalnych tkanki ludzkiej oraz symulacji numerycznej zachowania tej tkanki. Na podstawie eksperymentu dokonuje się identyfikacji modelu materiałowego tkanki a następnie w celu wweryfikacji przeprowadza się symulacje numeryczną zachowania modelowanej struktury. Celem badań jest uzyskanie informacji przydatnych podczas leczenia przepuklin brzusznych u ludzi.
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Mechanical model of fascia-implant structure. Finite element simulation.
PublicationPraca dotyczy modelowania i symulacji syntetycznych implantów chirurgicznych stosowanych w leczeniu przepulin brzusznych metodą laparoskowpową. Prponowane są modele matematyczne a ich prawidłowość weryfikowana jest na podstawie badań doświadczalnych zachowania się modeli fizycznych wszczepionych implantów pod wpływem obciążeń wynikających z fizjologii człowieka. Nakreślona jest metodologia oceny trwałości połączenia siatki chirurgicznej...
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Mechanical properties and corrosion resistance of dissimilar stainless steel welds
PublicationW artykule przedstawiono właściwości mechaniczne oraz odporność korozyjną doczołowych złączy różnoimiennych stali odpornych na korozję, austenitycznej 316L oraz duplex 2205. Blachy o grubości 15 mm spawano automatycznie łukiem krytyn z różnymi energiami liniowymi. Wykazano, że właściwości mechaniczne złączy spełniają wymagania okrętowych towarzystw klasyfikacyjnych, natomiast najbardziej narażoną strefą złącza na działanie korozji...
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Thermal and dynamic mechanical analysis of cross-linked poly(esterurethanes)
PublicationW pracy przedstawiono wyniki badań termograwimetrycznych oraz termomechanicznych usieciowanch za pomocą styrenu i metakrylanu metylu poli(estrouretanów). Uzyskane wyniki pozwoliły stwierdzić, że stabilność termiczna poli(estrouretanów) jest wystarczająca do wielu zastosowań technicznych. Przeprowadzone analizy wykazały również, iż polimery sieciowane styrenem wykazują separację fazową.
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The optimized Rayleigh–Ritz scheme for determining the quantum-mechanical spectrum
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Physical, Chemical and Mechanical Properties of Novel Poly(Urethaneamideimide)s
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Mechanical Strength of MV Ship-switchgear During Fault Arc
PublicationIn the paper the analysis of pressure stressed in enclosure during fault arc inside switchgear is pre-sented as well. There is introduced the method based on determining stresses which are sum of tensile stresses (membrane) and deflection stresses. For tensile stresses nalysis the energy method, for unrestrainedly supported rectangular plate, was used. In the further part of the paper, the calculations and measurements results...
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Mechanical and Non-Destructive Testing of Plasterboards Subjected to a Hydration Process
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Mechanical Properties of Polyester Coated Fabric Subjected to Biaxial Loading
PublicationThe paper is focused on the comparison between uniaxial and biaxial laboratory test results for polyester coated fabric. A short literature review concerning coated woven fabrics with emphasis on biaxial tensile tests is presented. A description of the polyester-coated fabric under biaxial test by means of constitutive models and material parameter values is proposed. To establish the right values of the ultimate tensile strength,...
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Cyclic mechanical stress impact on protective properties of organic coatings
PublicationCelem pracy jest zaprezentowanie wyników badań wpływu cyklicznych naprężeń mechanicznych na układy powłoka/metal. Powtarzające się naprężenia mechaniczne zostały zidentyfikowane jako czynnik w znaczącym stopniu przyczyniający się do degradacji powłok. Próbki składające się z powłoki epoksydowej nałożonej na stal St3SAl poddano serii 21000 cykli naprężenie-odpuszczenie. Badania przeprowadzono w zakresie odkształceń elastycznych...
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Degradation of organic coatings subjected to alternating mechanical stress impact.
PublicationW pracy przedstawiono wyniki badań nad wpływem cyklicznych naprężeń mechanicznych na dwa rodzaje systemów powłokowych stosowanych do ochrony konstrukcji mostowych. Powłoki epoksydowe i winylowe poddano cyklom zginanie/odpuszczenie w granicach odkształceń elastycznych materiału podłoża. Stan powłok oceniano przy użyciu techniki elektrochemicznej spektroskopii impedancyjnej. Otrzymane wyniki porównano z zachowaniem analogicznych...
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Research and education at Faculty of Mechanical Engineering, Gdańsk University of Technology.
PublicationPrzedstawiono aktualną działalność naukowo-badawczą Wydziału Mechanicznego Politechniki Gdańskiej w 60-lecie jego istnienia - realizowaną w 11 Katedrach w ramach działalności statutowej, badań własnych, projektów badawczych KBN i umów z przemysłem. Omówiono proces dydaktyczny na studiach inżynierskich, magisterskich i doktoranckich. Scharakteryzowano prowadzone specjalności i podano zamierzenia w zakresie umiędzynarodowienia studiów...
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Fatigue damage evaluation of organic coatings subjected to mechanical stress
PublicationZnaczna liczba konstrukcji ulega niszczeniu zmęczeniowemu w wyniku oddziaływania cyklicznych naprężeń mechanicznych. Jednakże w dziedzinie organicznych powłok ochronnych czynnik ten pozostaje niedoceniany. W pracy dokonano porównania wpływu cyklicznych naprężeń mechanicznych na nowe i pre-eksponowane (w podwyższonej temperaturze lub promieniowaniu UV) powłoki epoksydowe.
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The impact of natural fibers’ characteristics on mechanical properties of the cement composites
PublicationThe paper reviews the properties of cement composites reinforced with short fibres. The effect of natural fibres was investigated: cotton, sisal, jute, ramie, bamboo, and synthetic fibres: polymer and polypropylene. It was noticed that the fibres change the consistency of the mixture up to 15%. In the composite flexural strength tests, a change in strength by +/− 8% was observed, depending on the type of fibres used. The research...
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Faculty of Mechanical Engineering in the Time of its 60th/100th Anniversary
PublicationScharakteryzowano historię Wydziału Mechanicznego w perspektywie 100. letniej tradycji kształcenia politechnicznego w Gdańsku oraz 60 lat Wydziału Mechanicznego Politechniki Gdańskiej. Omówiono kształcenie studentów, tematykę badawczą i innowacyjną oraz program obchodów Roku Jubileuszowego na Wydziale.
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Modelling and computer programmes for dynamie analysis of complex mechanical systems
PublicationPraca dokumentuje dokonania samodzielnych pracowników naukowych Wydziału Mechanicznego Politechniki Gdańskiej i ma na celu przedstawienie i rozpowszechnienie wyników badań prowadzonych na Wydziale, szczególnie w ramach grantów KBN, rozpraw doktorskich i habilitacyjnych w ostatnich kilku latach.