Filters
total: 3071
-
Catalog
- Publications 2214 available results
- Journals 23 available results
- Publishing Houses 2 available results
- People 75 available results
- Inventions 3 available results
- Projects 8 available results
- Laboratories 2 available results
- Research Teams 7 available results
- Research Equipment 1 available results
- e-Learning Courses 112 available results
- Events 15 available results
- Open Research Data 609 available results
displaying 1000 best results Help
Search results for: Stefan Chwin
-
Effect of modified soybeen oil amount on rheological characteriza-tion of polyurethane pre-polymers
PublicationPolyurethanes (Pu’s) are the polymeric materials which have got urethane groups in the structure. The properties of Pu’s depend both on the method of preparation and monomers used. Polyurethanes are produced by two methods known as one step or two step method called as “pre-polymers method”, especially for the case of segmented polyurethanes (SPU’s). These materials are thermoplastic block copolymers of the (AB)n type consisting...
-
Synthesis, structure and properties of poly(ester-urethane)s obtained using bio-based and petrochemical1,3-propanediol and 1,4-butanediol
PublicationIn this paper, the poly(ester-urethane)s obtained using petrochemical and bio-based chain extenders were prepared and characterized. The influence of glycols’ origin on the chemical structure, mechanical and thermal properties of the prepared polyurethanes was studied. The materials were synthesised by prepolymer method. The first step involved the reaction of α,ω-dihydroxy(ethylene-butylene adipate (POLIOS 55/20) with 4,4’-diphenylmethane...
-
Synthesis and characterization of novel aliphatic polyurethanes for tissue engineering applications
PublicationSummarizing, in this thesis was described the synthesis of novel PUR system, which was obtained by using aliphatic diisocyanate (HDI), amorphous macrodiol (PEBA) and chain extender (BDO). This PUR system was established as suitable for TE purpose and successfully modified with AA, which as expected improved its biocompatibility. According to this, AA-modified HDI-based PURs is the PUR system ready for further studies including...
-
Heat turbomachinery
e-Learning Courses1. Steam turbine cycles. 2. Gas turbine cycles. 3. Combined gas-steam cycles. 4. Flows in nozzles. 5. Theory of turbine stages. 6. Multistage turbines. 7. Examples of turbine design.
-
Numerical modelling of moored floating structures using SPH. Preliminary results
PublicationThis article presents partial results of the works carried out under the research project "The development of the methodof modeling the dynamics of the floating (offshore) objects subjected to the environment influence", which aims at developing computational methods for modeling the dynamics of offshore structures.The article contains the description of the method of modeling the hydrodynamic impacts using SPH method and the description...
-
Two families of infinitely many homoclinics for singular strong force Hamiltonian systems
PublicationWe are concerned with a planar autonomous Hamiltonian system with a potential possessing a single well of infinite depth at a point X and a unique strict global maximum 0 at a point A. Under a strong force condition around the singularity X, via minimization of an action integral and using a shadowing chain lemma together with simple geometrical arguments, we prove the existence of infinitely many geometrically distinct homoclinic...
-
Book Chapter in the Prime Archives in Chemistry: 2nd Edition (dissemination of knowledge)
PublicationTo cite a chapter in a book include: Jaroslaw Spychala. The CON−H….+NH2 Blue-Shifting H-Bond Stabilizing Effect on Z Secondary Amides and Cyclic System Conformational Rearrangement through an Alkylamine-Chain Migration Pathway. In: VSR Rajasekhar Pullabhotla, editor. Prime Archives in Chemistry: 2nd Edition. Hyderabad, India: Vide Leaf. 2022. https://doi.org/10.1155/2022/1707245
-
On mixing in the class of quadratic stochastic operators
PublicationWe study different types of limit behavior of quadratic stochastic operators acting on ℓ^1 (or ℓ^1_d) spaces in both strong and uniform topologies. The main motif of the paper is to express the uniform and strong asymptotic stability of the quadratic stochastic operator in terms of convergence of the associated (linear) nonhomogeneous Markov chain. We also examine which type of uniform convergence of iterates of the quadratic...
-
Krzysztof Druet dr inż.
People -
Polnische Vertreter des Stahlbaus.
PublicationPodano rozszerzone notki biograficzne trzech wybitnych naukowców polskich - prof. Feliksa Jasińskiego, prof. Maksymiliana Tytusa Hubera, prof. Stefana Bryły oraz znakomitego konstruktora mostów - Polaka działającego w USA Rudolfa (Ralpha) Modrzejewskiego (Modejskiego).
-
Can sodium 1-alkylsulfonates participate in the sodium dodecyl sulfate micelle formation?
PublicationThe aggregation behavior of sodium dodecyl sulfate (SDS) was studied in an aqueous solution in the presence of increasing concentrations of selected sodium 1-alkylsulfonates, namely sodium 1-octanesulfonate, sodium 1-decanesulfonate, and sodium 1-dodecanesufonate. The critical micelle concentration (CMC) of SDS was determined by conductivity and fluorescence intensity measurements. The steady-state fluorescence quenching experiments...
-
ESCASA : Analytical estimation of atomic coordinates from coarse‐grained geometry for nuclear‐magnetic‐resonance ‐assisted protein structure modeling. I. Backbone and Hβ protons
PublicationA method for the estimation of coordinates of atoms in proteins from coarse-grained geometry by simple analytical formulas (ESCASA), for use in nuclear-magnetic-resonance (NMR) data-assisted coarse-grained simulations of proteins is proposed. In this paper, the formulas for the backbone Hα and amide (HN) protons, and the side-chain Hβ protons, given the Cα-trace, have been derived and parameterized, by using the interproton distances...
-
Dis/Trust and data-driven technologies
PublicationThis concept paper contextualises, defines, and systematises the concepts of trust and distrust (and their interrelations), providing a critical review of existing literature so as to identify gaps, disjuncture, and continuities in the use of these concepts across the social sciences and in the context of the consolidation of the digital society. Firstly, the development of the concept of trust is explored by looking at its use...
-
Wykorzystanie modelu układu regulacji prędkości kątowej hydrozespołu w adaptacyjnej metodzie synchronizacji prądnic
PublicationW artykule przedstawiono sposób wykorzystania modelu układu regulacji prędkości kątowej elektrowni wodnych pracujących przy dużym spadzie i długich rurociągach, w adaptacyjnej metodzie synchronizacji prądnic. Zaprezentowano algorytm identyfikacji wybranych parametrów modelu oraz wyniki badań symulacyjnych. Przedstawiono także sposób wykorzystania modelu do wyznaczenia chwil czasu, w których jest możliwe spełnienie warunków synchronizacji.
-
Manufacturing Techniques 1, W, L, Energy Tech., sem.02, letni22/23
e-Learning Courses -
Maria Jolanta Milewska prof. dr hab. inż.
PeopleMaria Jolanta Milewska, po ukończeniu Technikum Chemiczno-Mechanicznego w Wąbrzeźnie (specjalizacja: przetwórstwo tworzyw sztucznych) kontynuowała naukę na Wydziale Chemicznym Politechniki Gdańskiej. W 1979 r. zdobywa tytuł mgr inżyniera na kierunku Chemia, o specjalizacji Lekka Synteza Organiczna. Studium Doktoranckie PG ukończyła w 1984 r. W 1983 r została zatrudniona na macierzystym wydziale w Katedrze Chemii Organicznej, początkowo...
-
Microstructure and corrosion behaviour of carbon steel and ferritic and austenitic stainless steels in NaCl solutions and the effect of p-nitrophenyl phosphate disodium salt
PublicationThe microstructure and corrosion behavior of carbon steel (CSA516) and ferritic (SS410) and austenitic (SS304L) stainless steels were studied and compared. Corrosion tests were carried out in 0.5 M NaCl solutions. Rates of corrosion were monitored based on weight loss, Tafel extrapolation and linear polarization resistance (LPR) methods. Rates of corrosion were ranked following the order: CSA516 >> SS410 > SS304L. The impact of...
-
The change of mechanical properties of selected wood species after drying process under various conditions
PublicationThe result of mechanical properties change of selected wood species after drying process under various parameters are presented. The global elasticity modulus and bending strength for steam dried, air-steam mixture dried and air dried samples as reference were measured. It allowed to reveal the effect of wood stream, air-steam mixture and their temperature on mechanical properties of wood. It has been recognized that steam and...
-
Mashup Approaches for Improving Service Oriented Business Scenarios
PublicationTwo kinds of business scenarios are considered: application- and service-oriented. It is shown that the former are more flexible and easier reconfigurable for both traditional (human-oriented) and IT services. Moreover, complex IT services can be created by simple IT services using the modern mashup technology. It is the reason why such business scenarios can be modeled by BPMN in much easier ways. A simple example of a supply...
-
Crystal Structure of N-(2-Benzoyl-4,5-dimethoxyphenethyl)-2-phenylacetamide
PublicationThe crystal structure of N-(2-benzoyl-4,5-dimethoxyphenethyl)-2-phenylacetamide indicates that the compound crystallizes in the monoclinic C2/c space group with eight molecules in the unit cell. The heteroatoms from the amide group form a chain of intermolecular N-H ··· O hydrogen bonds propagating along the b axis. The carbonyl group from the benzoyl substituent participates in short contacts with two H-atoms from the ethyl or...
-
Systemy zarządzania i ich certyfikacja w przedsiębiorstwach spożywczych
PublicationW opracowaniu ukazano rolę obligatoryjnych systemów jakości odpowiedzialnych za bezpieczeństwo żywności z punktu widzenia przedsiębiorcy. W pracy omówiono wybrane systemy (GMP/GHP, HACCP) oraz certyfikację systemu HACCP obowiązującą normą ISO 22000. Przedstawiono również liczbę certyfikacji Systemu Zarządzania Bezpieczeństwem Żywności – Wymagania dla organizacji w całym łańcuchu żywnościowym w latach 2007-2011 w Polsce i na świecie,...
-
A Framework for Searching in Graphs in the Presence of Errors
PublicationWe consider a problem of searching for an unknown target vertex t in a (possibly edge-weighted) graph. Each vertex-query points to a vertex v and the response either admits that v is the target or provides any neighbor s of v that lies on a shortest path from v to t. This model has been introduced for trees by Onak and Parys [FOCS 2006] and for general graphs by Emamjomeh-Zadeh et al. [STOC 2016]. In the latter, the authors provide...
-
CBR methodology application in an expert system for aided design ship's engine room automation
PublicationW artykule przedstawiono metody obliczania podobieństwa na podstawie przypadków, zastosowane w opracowanym systemie ekspertowym do wspomagania projektowania siłowni okrętowej. Do realizacji metody na przykładzie automatyki napędu głównego zastosowano oprogramowanie bazy danych i system ekspertowy. Uzyskane wyniki wyszukiwania w bazie danych statków podobnych zostały porównane i przeanalizowane. Do weryfikacji zastosowanych w bazie...
-
Modelowanie i symulacja procesu nadzorowania drgań w układzie hybrydowym na przykładzie frezowania przedmiotów podatnych.
PublicationPraca dotyczy nadzorowania drgań niestacjonarnych układów mechanicznych za pomocą sterowania optymalnego przy energetycznym wskaźniku jakości. W układzie drgającym wyodrębniono podukład modalny, podukład strukturalny oraz podukład łączący. Dynamikę układu sterowanego opisano we współrzędnych hybrydowych. Przedstawiono przykład nadzorowania drgań podczas skrawania przedmiotów podatnych frezem kulistym.
-
ZUŻYCIE POWIERZCHNI KULEK CERAMICZNYCH W PROCESIE NAGNIATANIA TOCZNEGO STALI HARTOWANEJ
PublicationPrzedstawiono wyniki z badań eksperymentalnych dotyczących przydatności kulek wykonanych z ceramiki technicznej, do nagniatania tocznego, narzędziami z dociskiem hydrostatycznym. W przeprowadzonych badaniach zastosowano narzędzie umożliwiające wymianę kulek ceramicznych zastosowanych jako elementów nagniatające. Badania wykonano poprzez nagniatanie próbek - wałków wykonanych ze stali Cf53 w stanie utwardzonym (zahartowanym). Wyniki...
-
Mobility and biodegradability of an imidazolium based ionic liquid in soil and soil amended with waste sewage sludge
PublicationSorption on solids and biodegradation are main phenomena that can mitigate the pollution of soil and water by ionic liquids (ILs). ILs sorbed on soil particles become immobilized (temporarily or permanently) which prevents them from spreading into deeper layers of soil or groundwater but which also makes them less bioavailable. In this study we attempt to examine if amendment of soil with waste sludge has a potential to mitigate...
-
Detrimental effects of chemotherapeutics and other drugs on the endothelium: A call for endothelial toxicity profiling
Publication -
Ocena stanu powierzchni kulek ceramicznych po nagniataniu tocznym stali hartowanej Cf53
PublicationW artykule przedstawiono wyniki z badań eksperymentalnych dotyczących przydatności kulek wykonanych z ceramiki technicznej, do nagniatania tocznego, narzędziami z dociskiem hydrostatycznym. W badaniach wykorzystano narzędzie umożliwiające wymianę kulek nagniatających. Badania wykonano poprzez nagniatanie wałków wykonanych ze stali Cf53 w stanie utwardzonym (zahartowanym). Wyniki badań obejmują charakterystyki stanu powierzchni...
-
Automated Diagnostics of Current Pick-Up Disturbances in Electric Traction Networks
PublicationThe present work defines the basic causes of bow disturbances of current pick-up, sets a task of establishing a system of automated control of bow disturbances at feeder zones of electric traction networks, proposes structural variants of the technical system implementation, describes the algorithm of detection of bow disturbances of current pick-up.
-
Development and application of asphalt binder relaxation test in different dynamic shear rheometers
PublicationIn this study, a novel relaxation test is proposed to evaluate asphalt binder low temperature properties using a Dynamic Shear Rheometer (DSR) with parallel plates of 4 mm in diameter. Three rheometers from three different manufacturers are used to analyze seven asphalt binders. Different material parameters are derived which are useful to evaluate and discriminate different asphalt binders. Test results of all three instruments...
-
Różnica w subiektywnej ocenie jakości mowy pomiędzy nastolatkami dwujęzycznymi a jednojęzycznymi
PublicationProces percepcji mowy omawiany jest w szerokim zakresie dziedzin i dyscyplin naukowych, od nauk humanistycznych, technicznych, aż po nauki medyczne. Wiele badań skupia się np. na ocenie różnicy w grupach bez i z wykształceniem muzycznym. Skoro stwierdzono, że zdolności muzyczne wpływają na percepcję poszczególnych atrybutów dźwięku, autorzy postanowili zbadać, czy zdolności językowe także mogą mieć wpływ na ocenę jakości sygnału...
-
XVIII Międzynarodowe Sympozjum Inżynierii i Reżyserii Dźwięku
PublicationThe subjective assessment of speech signals takes into account previous experiences and habits of an individual. Since the perception process deteriorates with age, differences should be noticeable among people from dissimilar age groups. In this work, we investigated the difference of speech quality assessment between high school students and university students. The study involved 60 participants, with 30 people in both the adolescents...
-
Physical crosslinking of hyaluronic acid in the presence of phospholipids in an aqueous nano-environment
PublicationHyaluronic acid and phospholipids are two components in the synovial joint cavity that contribute to joint lubrication synergistically. Molecular dynamics simulations were performed and hydrogen bonds in hyaluronic acid were analyzed to identify specific sites that are responsible for its physical cross-linking. Two molecular masses of hyaluronic acid, 10 kDa and 160 kDa, were considered. We use molecular dynamics simulations and...
-
Structure and Molecular Dynamics in Renewable Polyamides from Dideoxy-Diamino Isohexide
PublicationThe chemical structure, the conformation, andthe flexibility of the polymer chain fragments present in thepolyamides synthesized from 2,5-diamino-2,5-dideoxy-1,4;3,6-dianhydrosorbitol, 1,4-diaminobutane, and either sebacic orbrassylic acid have been studied by liquid-state 2D NMRspectroscopy viz. correlation spectra (COSY) and heteronuclearmultiple-bond correlation spectra (gHMBC), by 13Ccross-polarization/magic-angle spinning...
-
Dimeric structure of the N-terminal domain of PriB protein from Thermoanaerobacter tengcongensis solved ab initio
PublicationPriB is one of the components of the bacterial primosome, which catalyzes the reactivation of stalled replication forks at sites of DNA damage. The N-terminal domain of the PriB protein from the thermophilic bacterium Thermoanaerobacter tengcongensis (TtePriB) was expressed and its crystal structure was solved at the atomic resolution of 1.09 Å by direct methods. The protein chain, which encompasses the first 104 residues of the...
-
Privacy-Preserving, Scalable Blockchain-Based Solution for Monitoring Industrial Infrastructure in the Near Real-Time
PublicationThis paper proposes an improved monitoring and measuring system dedicated to industrial infrastructure. Our model achieves security of data by incorporating cryptographical methods and near real-time access by the use of virtual tree structure over records. The currently available blockchain networks are not very well adapted to tasks related to the continuous monitoring of the parameters of industrial installations. In the database...
-
Copper(I) halide cluster-based coordination polymers modulated by chiral ditopic dithiodianthranilide ligands: synthesis, crystal structure and photoluminescence
PublicationReaction of copper(I) halides with chiral dithiodianthranilidesmdtaandbdtaafforded polymeric complexeswhere polynuclear CuX clusters were linked together by ditopic bridging ligands into 1D chains or 2D layerstructures. In the case of racemic ligands double stranded chain polymers were formed where the Cu4X4(X = I or Br) cores are connected by enantiomeric pairs of the ditopic ligands. In contrast, a homochiralmdtaligand created...
-
Accuracy Investigations of Turbine Blading Neural Models Applied to Thermal and Flow Diagnostics
PublicationPossibility of replacing computional fluid dynamics simulations by a neural model for fluid flow and thermal diagnostics of steam turbines is investigated. Results of calculations of velocity magnitude of steam for 3D model of the stator of steam turbine is presented.
-
Sensitivity analysis of buckling loads of bisymmetric I-section columns with bracing elements
PublicationWyznaczono pierwsza wariacje siły krytycznej wyboczenia słupa o przekroju bisymetrycznym otwartym przy wariacji sztywnosci i połozenia stezen. Przyjeto załozenia klasycznej teorii pretów cienkosciennych o nieodkształcalnym przekroju poprzecznym. Analizowano zarówno stezenia boczne jak i stezenia ograniczajacespaczenie oraz skrecenie przekroju poprzecznego. Stezenia modelowano jako podpory sprezyste. W przykładzie numerycznym zbadano...
-
Simulation of ship spiral test for ballast and full load conditions
Open Research DataThe data show the results of the spiral test for the simplified ship model, taking into account two states of loading: ballast and full load. The data set contains the results of time simulation for sea state 10 on the Beaufort scale: changes in rudder angle delta_tab[deg]; angular velocity r_tab[deg/s]; surge velocity u_tab (m/s); sway velocity v_tab...
-
SEI Growth and Depth Profiling on ZFO Electrodes by Soft X-Ray Absorption Spectroscopy
PublicationZnFe2O4 (ZFO) Li-ion batteries (LIBs) represent a reliable, affordable, and safe energy storage technology for use in portable application. However, current LIB active materials (graphite, lithium/transition metal spinel or layered oxides, olivine structures) can store only limited energy since they rely on insertion storage based on solid-state host-guest interactions. Moreover, performances and durability of the cells are strongly...
-
Physical properties of homogeneous TiO2 films prepared by high power impulse magnetron sputtering as a function of crystallographic phase and nanostructure
PublicationOptical, photo-electrochemical, crystallographic and morphological properties of TiO2 thin films prepared by high power impulse magnetron sputtering at low substrate temperatures (<65 ◦C) without post-deposition thermal annealing are studied. The film composition-anatase, rutile or amorphous TiO2-is adjusted by the pressure (p ∼ 0.75-15 Pa) in the deposition chamber. The different crystallographic phases were determined with grazing...
-
Prezentacja instalacji artystycznej "Mam dla Ciebie moje serce" na wystawie zbiorowej „WETWARE: PROLIFERACJA I PRZECZUCIE” w Instytucie Cybernetyki Sztuki
Publication„WETWARE: PROLIFERACJA I PRZECZUCIE” Marcin Bożek, Marta Branicka, Flora Ćwirko + Jan Maurycy Adamski, Jowan Czerkas, Urszula Dulewicz, Dorota Grubba Thiede + Danuta Ćwirko Godycka, Tomasz Kopcewicz, Marta Koniarska, Maria Krupa, Monika Krygier + Stefan Krygier + Włodzimierz Pietrzyk, Przemysław Kryszk, Ryszard Ługowski, Krzysztof Malec, Anna Malinowska, Andrzej Egon Fietke Miastkowski, Piotr Tadeusz Mosur, Mateusz Pęk, Katarzyna...
-
Integrable zero-range potentials in a plane
PublicationWe examine general statements in the Wronskian representation of Darboux transformations for plane zero-range potentials. Such expressions naturally contain scattering problem solution. We also apply Abel theorem to Wronskians for differential equations and link it to chain equations for Darboux transforms to fix conditions for further development of the underlying distribution concept. Moutard transformations give a convenient...
-
Fundamentals of thermodynamics and heat transfer, W/C, GTM (WCh), sem.04, zimowy 23/24 (PG_00048767)
e-Learning CoursesTable of contents presented on the course: Basic terms.The first law of thermodynamics for closed and open systems.The properties of perfect, semi-perfect and real gases.Gas rights. Thermal and caloric state equation.Thermodynamic transformations of a perfect gas.Gaseous thermodynamic cycles. The second law of thermodynamics.Steam and steam cycles.Basics of heat exchange.
-
Effect of molar ratio [NCO]/[OH] groups during prepolymer chains extending step on the morphology and selected mechanical properties of final bio‐based thermoplastic poly(ether‐urethane) materials
PublicationThe main aim of this work was to investigate the effect of [NCO]/[OH] molar ratio used during the prepolymer chain extending step (with bio‐based diols) on the chemical structure, and thermomechanical and mechanical properties of thermoplastic poly(ether‐urethane)s. Thermoplastic poly(ether‐urethane)s were obtained from bio‐based polyol (polytrimethylene ether glycol), bio‐based glycol (1,4‐butanediol or 1,3‐propanediol), and 4,4'diphenylmethane...
-
Structure, morphology and mechanical behaviour of novel bio-based polyurethane composites with microcrystalline cellulose
PublicationThe aim of this work was to obtain bio-based polyurethane composites using biocomponents such as, bio-glycol, modified natural oil-based polyol, and microcrystalline cellulose (MCC). The prepolymer method was used to prepare the bio-based polyurethane matrix. Prepolymer synthesised from 4,4’-diphenylmethane diisocyanate (MDI) and a polyol mixture containing 75% wt. commercial polyether and 25% wt. hydroxylated soybean oils (H3)...
-
Thermo-oxidative exfoliation of carbon black from ground tire rubber as potential reinforcement in green tires
PublicationConsidering the balance between rapidly growing global tire demand and scarcity of natural resources, recycling and reclaiming techniques of tire rubber have become the state of the art. Herein, we set out to implement a self-designed thermo-oxidative reactor for the exfoliation of carbon black (CB) from ground tire rubber, which is efficiently functioned under a thermo-oxidative reclaiming condition without any additive. The exfoliation...
-
Phylogenetic trees of genus Oncidium Sw. based on analysis of DNA sequences
Open Research DataGenus Oncidium Sw. is widely regarded as a polyphiletic, and the taxonomic boundaries between him and such genera as Odontoglossum Kunth. or Miltonia Lindley remain blurred. The goal of the study was to determine the phylogenetic relationships within the genus Oncidium s.lato based on the DNA sequences analysis. The correlation between molecular data...
-
Krystyna Nagrodzka-Godycka prof. dr hab. inż.
People