Filters
total: 1716
filtered: 851
Search results for: DEGREE OF MONOPOLY
-
Influence of e-beam irradiation on poly(aliphatic/aromatic-ester) multiblock copolymers used as biomaterials
PublicationThe use of polymers became more relevant in medical applications for the versatility in processing and enhanced material properties of polymers. In order to be suitable as a biomaterial, it is of medical importance that these polymers are biocompatible and do not elicit negative responses from the body after implantation. Furthermore during the course of usage under load-bearing conditions, these biomaterials must sustain dynamical...
-
Fast multi-objective optimization of antenna structures by means of data-driven surrogates and dimensionality reduction
PublicationDesign of contemporary antenna structures needs to account for several and often conflicting objectives. These are pertinent to both electrical and field properties of the antenna but also its geometry (e.g., footprint minimization). For practical reasons, especially to facilitate efficient optimization, single-objective formulations are most often employed, through either a priori preference articulation, objective aggregation,...
-
New Materiality-towards ‘Media Environments
PublicationArticle presents media solutions providing new materiality of architectural spaces. Media solutions in architecture evolve in new forms. Articlepresentsboth the developmentof new technological solutionsas well as new ways of application of media solutions in relation toarchitectural form. The aim of the article is to show technical aspects of new materiality - intelligent materials, allowing transmission of changeable visual content...
-
Preliminary Testing of the Influence of Modified Polycaprolactones on Anabaena Variabilis Growth in Seawater
PublicationSeveral new biodegradable polymer materials have recently come onto the global market. Mostly the results on degradation kinetic studies are presented. This paper suggests using one of the tests to estimate the impact of polymer packaging material on sea life. The microorganism chosen was Anabaena variabilis (identified in many waters, including those of the Baltic Sea, especially in the Gulf of Gdansk and Puck Bay; this cyanobacterium...
-
The influence of chemical composition of amide block on the thermal properties and structure of terpoly(ester-b-ether-b-amide) elastomers
PublicationMultiblock terpolymers-(PBT-b-PTMO-b-PA12,10)(n)- constituting the polymer systems, in which one of the three blocks (PBT) does not dissolve in PA12,10 block (hard phase) and, depending on its molecular weight is slightly soluble in PTMO block (soft phase), have been obtained. The DSC method was applied to investigate the thermal properties of these polymers and it was found that PBT block acts as an element that produces stiffness...
-
Thermal Transitions and Structural Characteristics of Poly(3,4-ethylenedioxythiophene/cucurbit[7]uril) Polypseudorotaxane and Polyrotaxane Thin Films
PublicationHerein, we report the thermal transitions and structural properties of poly(3,4-ethylenedioxythiophene/cucurbit[7]uril) pseudopolyrotaxane (PEDOT∙CB7-PS) and polyrotaxane (PEDOT∙CB7-PR) thin films compared with those of pristine PEDOT. The structural characteristics were investigated by using variable-temperature spectroscopic ellipsometry (VTSE), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and atomic force...
-
Evolution of the nanostructure of Pt and Pt–Co polymer electrolyte membrane fuel cell electrocatalysts at successive degradation stages probed by X-ray photoemission
PublicationWe present a set of XPS (X-ray photoemission spectroscopy) measurements and detailed data-analysis of electrodes for polymer electrolyte membrane fuel cell (PEMFC) based on carbon supported catalysts (Pt and Pt–Co) subjected to a step-like potential cycling (accelerated degradation test). The results of the measurements complete and corroborate parallel TEM (transmission electron microscopy), XRD (X-ray diffraction) and XAS (X-ray...
-
Direct amination of boron-doped diamond by plasma polymerized allylamine film
PublicationA novel microwave pulsed-plasma based method for the modification of the hydrogen-terminated polycrystalline boron-doped diamond (BDD) with a thin film of polymerized allylamine (PPAAm) is reported. A modified BDD surface is resistant to hydrolysis and delamination and is characterized by a high density of positively charged amino groups. Pulsed microwave plasma was applied to improve the degree of cross-linking and bonding of...
-
An evaluation and explanation of (in)efficiency in higher education institutions in Europe and the U.S. with the application of two-stage semi-parametric DEA
PublicationThis study uses data envelopment analysis (DEA) to evaluate the relative efficiency of 500 higher education institutions (HEIs) in ten European countries and the U.S. for the period between 2000 and 2010. Efficiency scores are determined using different input-output sets (inputs: total revenue, academic staff, administration staff, total number of students; outputs: total number of publications, number of scientific articles, graduates)...
-
Macroeconomic functions of the Russian stock market
PublicationThe purpose of this article is to present the structure of the stock market in the Russian Federation and the significance of this part of national financial system for the whole economy, particularly the degree of main macroeconomic functions fulfillment. First part of the text includes an overview of the main theoretical concepts linked with the stock market roles as well as a brief description of results of selected studies...
-
Graph Decomposition for Memoryless Periodic Exploration
PublicationWe consider a general framework in which a memoryless robot periodically explores all the nodes of a connected anonymous graph by following local information available at each vertex. For each vertex v, the endpoints of all edges adjacent to v are assigned unique labels within the range 1 to deg (v) (the degree of v). The generic exploration strategy is implemented using a right-hand-rule transition function: after entering vertex...
-
High-temperature oxidation of the Crofer 22 H ferritic steel with Mn1.45Co1.45Fe0.1O4 and Mn1.5Co1.5O4 spinel coatings under thermal cycling conditions and its properties
PublicationThe aim of the presented study was to deposit protective-conducting Mn1.45Co1.45Fe0.1O4 and Mn1.5Co1.5O4 spinel coatings on the Crofer 22 H ferritic steel by means of electrophoresis and to evaluate their physicochemical properties after high-temperature oxidation under thermal cycling conditions. When the Crofer 22 H steel – whether uncoated or coated with the two spinels – was oxidized in 48-h cycles involving a temperature of...
-
Curing epoxy with electrochemically synthesized Zn Fe3-O4 magnetic nanoparticles
PublicationCathodic electrodeposition (CED) was applied in synthesis of undoped and zinc (Zn) doped Fe3O4 nanoparticles. Changes in the lattice structure of nanoparticles were monitored using X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) supported by dispersive X-ray spectrometry (EDS), and vibrating sample magnetometry (VSM). Detailed analyses explored the formation of ZnxFe3–xO4 nanoparticles with x ≈ 0.1,...
-
Reclaimed rubber in-situ grafted with soybean oil as a novel green reactive plasticizer in SBR/silica compounds
PublicationPolymer recycling and biodegradable polymeric materials are two major routes towards the sustainable development of polymer materials which contributes to the management of waste. In this regard, an eco-friendly approach is presented wherein high reclaiming degree of ground tire rubber (GTR) was achieved by low-temperature oxidation under swollen action of soybean oil. In-situ reclaimed GTR with soybean oil was cured into reactive...
-
Optimization of Saccharification Conditions of Lignocellulosic Biomass under Alkaline Pre-Treatment and Enzymatic Hydrolysis
PublicationPre-treatment is a significant step in the production of second-generation biofuels from waste lignocellulosic materials. Obtaining biofuels as a result of fermentation processes requires appropriate pre-treatment conditions ensuring the highest possible degree of saccharification of the feed material. An influence of the following process parameters were investigated for alkaline pre-treatment of Salix viminalis L.: catalyst concentration...
-
Novel monovalent and multivalent recombinant proteins of Borrelia burgdorferi sensu lato with potential diagnostic value – construction and biotechnological production
PublicationThe diverse antigenic structure of Borrelia burgdorferi sensu lato (s.l.) and the low degree of protein sequence conservation between genospecies causes many limitations in serodiagnosis of Lyme disease (LD). Using expression systems based on Escherichia coli, five monovalent B. burgdorferi s.l. recombinant proteins were produced. i.e., BB0108, BB0126, BB0298, BB0323, BB0689 (each in three variants derived from Borrelia afzelii,...
-
Thermosensitive composite based on agarose and chitosan saturated with carbon dioxide. Preliminary study of requirements for production of new CSAG bioink.
PublicationThis study introduces a method for producing printable, thermosensitive bioink formulated from agarose (AG) and carbon dioxide-saturated chitosan (CS) hydrogels. The research identified medium molecular weight chitosan as optimal for bioink production, with a preferred chitosan hydrogel content of 40–60 %. Rheological analysis reveals the bioink's pseudoplastic behavior and a sol-gel phase transition between 27.0 and 31.5 °C. The...
-
Laser-Induced Graphitization of Polydopamine on Titania Nanotubes
PublicationSince the discovery of laser-induced graphite/graphene, there has been a notable surge of scientific interest in advancing diverse methodologies for their synthesis and applications. This study focuses on the utilization of a pulsed Nd:YAG laser to achieve graphitization of polydopamine (PDA) deposited on the surface of titania nanotubes. The partial graphitization is corroborated through Raman and XPS spectroscopies and supported...
-
Rural Building in Opole Silesia During the Period of the Frederician Colonization
PublicationThe aim of the article is to present the rural construction in the Opole countryside (Poland) during the “Frederician colonization”. Showing socio-economic areas of Opole villages, differing from each other, the differences of which resulted from the environmental conditions influencing the processes of enfranchisement and industrialization. These processes at the turn of the 17th and 19th centuries influenced the image of the...
-
Cross-Linking, Morphology, and Physico-Mechanical Properties of GTR/SBS Blends: Dicumyl Peroxide vs. Sulfur System
PublicationIn this work, ground tire rubber and styrene–butadiene block copolymer (GTR/SBS) blends at the ratio of 50/50 wt%, with the application of four different SBS copolymer grades (linear and radial) and two types of cross-linking agent (a sulfur-based system and dicumyl peroxide), were prepared by melt compounding. The rheological and cross-linking behavior, physico-mechanical parameters (i.e., tensile properties, abrasion resistance,...
-
GUIDED WAVES IN SHIP STRUCTURAL HEALTH MONITORING – A FEASIBILITY STUDY
PublicationShips and offshore structures operate in a severe corrosion degradation environment and face difficulty in providing long- lasting corrosion protection. The Classification Societies recommend regular thickness measurements leading to structural component replacements, to ensure structural integrity during service life. The measurements are usually performed using ultrasonic thickness gauges and such an approach requires multiple...
-
Implementation of Hierarchical Control of Drinking Water Supply System
PublicationThe paper presents the outline of the didactical project of a complex computer controlled system realized by the first degree students of the Automatics and Robotics on the Faculty of Electrical and Control Engineering (FoEaCE) in Gdansk University of Technology (GUT). The synthesis, implementation and analysis of a multilayer hierarchical control system for drinking water supply system (DWSS) are main topics of that project. The...
-
Bioavailability of Tannins and Other Oligomeric Polyphenols: a Still to Be Studied Phenomenon
PublicationPurpose of Review Polyphenols are a group of plant secondary metabolites characterized with the presence ofmultiples of phenol structural units. Tannins are plant originated phenolic substances, which play an important role in plant defense system as well as have found applications in medicine, industry, and other fields of human activity. Despite these, the mechanisms of bioavailability of these substances are poorly studied and...
-
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...
-
PRINCIPLES OF ARTIFICIAL INTELLIGENCE APPLICATION IN CONTROL OF THE ENTERPRISE
PublicationThe implementation of the tasks of evaluating historical financial information, the control or audit of business activities are based primarily on professional judgments about the object of study of a professional accountant or auditor. Their findings are drawn on the basis of the study of documents, the use of audit evidence, risk assessment, etc. There is always a probability (and rather high) that professional judgment will...
-
3D X-ray Micro-CT Analysis of Rebar Corrosion in Reinforced Concrete Subjected to a Chloride-Induced Environment
PublicationThe paper presents experimental investigations of the concrete cover protective ability to coun-teract rebar corrosion in reinforced concrete cubes. To study and quantify the consequences of corrosion a reinforced concrete sample was subjected to chloride-induced environment in order to get corroded and combined with un-corroded sample. Chloride-accelerated technique can in-duce a high degree of corrosion within at a controlled...
-
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...
-
Load path sensitivity and multiaxial fatigue life prediction of metals under non-proportional loadings
PublicationEngineering components often operate under complex loadings, in which the variable amplitude multiaxial stresses are raised by geometric discontinuities including holes, grooves, fillets and shoulders, etc. Besides, the non-proportional loading will lead to the rotation of maximum principal stress/strain and additional fatigue damage of structural elements in service. Consequently, the multiaxial and non-proportional loading have...
-
Towards azeotropic MeOH-MTBE separation using pervaporation chitosan-based deep eutectic solvent membranes
PublicationDeep eutectic solvents (DESs) are a new class of solvents that can offset some of the major drawbacks of common solvents and ionic liquids. When dealing with the preparation of dense membranes, the use of DESs is still challenging due to their low compatibility with the polymer phase. In this research, a novel L-proline:sulfolane (molar ratio 1:2) DES was synthesized and used for the preparation of more sustainable bio-based membranes...
-
Nonlinear generation of non-acoustic modes by low-frequency sound in a vibrationally relaxing gas
PublicationTwo dynamic equations referring to a weakly nonlinear and weakly dispersive flow of a gas in which molecular vibrational relaxation takes place. are derived. The first one governs an excess temperature associated with the thermal mode, and the second one describes variations in vibrational energy. Both quantities refer to non-wave types of gas motion. These variations are caused by the nonlinear transfer of acoustic energy into...
-
THE CONCEPT OF MODELING OF SNOW IMPACT ON THE STRUCTURE OF THE SUSPENDED TAURON ARENA ROOF IN CRACOW
PublicationThe article presents studies and numerical simulations on modeling snow influence on TAURON ARENA suspended roof structure in Cracow. The scope of work includes experimental tests, functions solutions taking into account various cases of snow impact according to PN and EC, as well as numerical simulations for the sport and entertainment arena in the Czyzyny district. The FEM roof structure model developed in the SOFISITK software...
-
Space and spatial practices in times of confinement. Evidence from three European countries: Austria, France and Poland
PublicationIn the first half of 2020, millions of people were subjected to drastic restrictions aimed at limiting the spread of the Covid-19 disease. Austria, France and Poland have implemented a lockdown to varying degrees and for varying lengths of time. This is an unprecedented situation in Europe: until now, even in times of war, curfew measures have never been applied 24 h a day. The research presented in this article was carried out...
-
Stress-driven nonlocal elasticity for nonlinear vibration characteristics of carbon/boron-nitride hetero-nanotube subject to magneto-thermal environment
PublicationStress-driven nonlocal theory of elasticity, in its differential form, is applied to investigate the nonlinear vibrational characteristics of a hetero-nanotube in magneto-thermal environment with the help of finite element method. In order to more precisely deal with the dynamic behavior of size-dependent nanotubes, a two-node beam element with six degrees-of freedom including the nodal values of the deflection, slope and curvature...
-
NON-LOCAL VOLUMETRIC APPROACH TO ANALYSIS DEFECT'S SHAPE INFLUENCE ON SPECIMENS DURABILITY SUBJECTED TO BENDING AND TORSION
PublicationThe influence of defect features on fatigue behaviour is a complex trivial issue. Although the important advances over the last decades, the dialectical relationship between the defect orientation and durability is not clearly understood. The paper aims at studying the influence of the orientation of elliptical defects on the durability of samples made of C45 steel. Three types of samples with elliptical defects were subjected...
-
An isogeometric finite element formulation for frictionless contact of Cosserat rods with unconstrained directors
PublicationThis paper presents an isogeometric finite element formulation for nonlinear beams with impenetrability constraints, based on the kinematics of Cosserat rods with unconstrained directors. The beam cross-sectional deformation is represented by director vectors of an arbitrary order. For the frictionless lateral beam-to-beam contact, a surface-to-surface contact algorithm combined with an active set strategy and a penalty method...
-
Soil contamination with geohelminths in children’s play areas in Szczecin, Poland
PublicationThe presence of invasive forms of parasites in the soil represents a potential threat to public health, especially for children. The aim of the study was to determine the degree of contamination with geohelminth eggs of soil samples collected from sandpits and playgrounds in the Szczecin area. The findings showed overall prevalence of soil samples contaminated with geohelminth eggs in the soil and sand...
-
Does the carbon emissions trading system reduce carbon emissions by promoting two-way FDI in developing countries? Evidence from Chinese listed companies and cities
PublicationHow developing countries can effectively promote cities’ carbon emission reduction through the carbon emission trading system (ETS) is a topic worthy of attention in the global carbon reduction campaign. Policy changes in China's ETS provide a unique opportunity to measure whether ETS impacts carbon emissions through two-way FDI. Hence, this paper employs difference-in-differences (DID) method to test the causal impact of ETS...
-
“Shadow” vs. “Phase 3D” method within endoscopic examinations of marine engines
PublicationA visual investigation of surfaces creating internal, working spaces of marine combustion engines by means of specialized view-finders so called endoscopes is at present almost a basic method of technical diag-nostics. The surface structure of constructional material is visible during investigations like through the magnifying glass (usually with a precisely determined magnification), which makes possible a detection, recognition...
-
Curing characteristics, mechanical properties and morphology of butyl rubber filled with ground tire rubber (GTR)
PublicationThe results on testing application of ground tire rubber (GTR), as potential filler for butyl rubber, are pre- sented. The GTR content variation, within the range of 10–90 phr, was studied with respect to the vulcanization process, static mechanical properties (tensile strength, elongation-at-break, hardness and resilience), dynamic mechanical properties and the morphology of the obtained vulcanizates. Butyl rubber was characterized...
-
Efficiency of thermomechanical reclaiming of ground tire rubber conducted in counter-rotating and co-rotating twin screw extruder
PublicationIn this article the results of research on a continuous thermomechanical reclaiming process of ground tire rubber (GTR) conducted in a twin screw extruder are presented. The effects of the rotation direction (co-rotating/counter-rotating), design of co-rotating plasticizing units and the rotational speed of the screws on the extruder working parameters, sol fraction and the degree of reclaiming in the obtained products were described....
-
Challenges in determination of pesticides from various chemical groups in fruits and vegetables applying QuEChERS method
PublicationPesticides are a large group of compounds with different physical and chemical properties, which place some of them among the most toxic, environmentally stable, and mobile substances. Nevertheless, their number, use, and application are continuously expanding. A consequence of their use is the possible presence of residues in treated food products. To protect consumers from exposure to unacceptable levels of pesticides Maximum...
-
Properties of nano-Fe3O4 incorporated epoxy coatings from Cure Index perspective
PublicationThe mission of an advanced epoxy-based nanocomposite coating is to provide a given substrate with protection against an unwelcome guest; e.g. corrosive molecules/media, environmental stress, flame, thermal degradation or microorganisms. In such systems, the degree to which superior properties can be guaranteed depends on the state of network formation in the epoxy in the presence of nanoparticles. For low-filled epoxy nanocomposite coatings,...
-
Interactions of N-alkyl-N-methylmorpholinium based ionic liquids with acetonitrile studied by density and velocity of sound measurements and molecular dynamics simulations
PublicationMorpholinium-based ionic liquids (ILs) and their mixtures with polar co-solvents are an interesting class of emerging electrolytes in electrochemistry that is relatively poorly studied. In this work, densities and sound velocities of four ILs, N-ethyl-N-methylmorpholinium tetrafluoroborate, N-butyl-N-methylmorpholinium tetrafluoroborate, N-octyl-N-methylmorpho-linium tetrafluoroborate and N-decyl-N-methylmorpholinium tetrafluoroborate...
-
In-depth characterization of icosahedral ordering in liquid copper
PublicationThe presence of icosahedral ordering in liquid copper at temperatures close to the melting point is now well-established both experimentally and through computer simulation. However, a more elaborate analysis of local icosahedral and icosahedron-like structures, together with a system for classifying such structures based on some measure of "icosahedrity", has so far been conspicuously absent in the literature. Similarly, the dynamics...
-
A three-dimensional periodic beam for vibroacoustic isolation purposes
PublicationThis paper presents results of investigations on a three-dimensional (3-D) isotropic periodic beam. The beam can represent a vibroacoustic isolator of optimised dynamic characteristics in the case of its longitudinal, flexural and torsional behaviour. The optimisation process concerned both the widths as well as the positions of particular frequency band gaps that are present in the frequency spectrum of the beam. Since the dynamic...
-
An overview of the cognitive and biological effects of city nighttime illumination including a London case study
PublicationCurrent scientific research demonstrates how critical the effects of city nighttime illumination are upon cognitive and biological health1 – which needs to be adequately acknowledged, understood and addressed by conscious cities and the plans they develop. Until recent decades, the design of nighttime lighting was determined mostly by electrical engineers who often applied technical standards to meet the requirements of vehicle-focused...
-
Fully Isohexide-Based Polyesters: Synthesis, Characterization, and Structure-Properties Relations
PublicationHere we present a novel series of biobasedpolyesters solely based on renewable isohexide building blocks,synthesized via melt polymerization. The recently developedisoidide dicarboxylic acid (IIDCA) was polymerized with rigidrenewable diols such as isosorbide (IS), isomannide (IM),isoidide (II), and the novel 2,5-methylene-extended isoididedimethanol (IIDML). Both IIDCA and IIDML weredeveloped to increase the reactivity of the...
-
Strategic balance in graphs
PublicationFor a given graph G, a nonempty subset S contained in V ( G ) is an alliance iff for each vertex v ∈ S there are at least as many vertices from the closed neighbourhood of v in S as in V ( G ) − S. An alliance is global if it is also a dominating set of G. The alliance partition number of G was defined in Hedetniemi et al. (2004) to be the maximum number of sets in a partition of V ( G ) such that each set is an alliance. Similarly,...
-
A fast and convenient method for analysis of collagen hydrolysis products Szybka i dogodna metoda analizy produktów hydrolizy kolagenu
PublicationPolypeptides produced by hydrolysis of collagen from minced animal hide and skin scraps were studied by mass spectrometry (MS) in conjunction with electrophoresis to det. their mol. mass. The degree of peptides ionisation was ca 50+. This allowed for observation of the large polypeptide chains with mass analyzers with a relatively low m/z range. The electrospray and atm. pressure photoionization techniques were used. The polypeptide...
-
MINERAL MATTER IN MUNICIPAL SOLID WASTE
PublicationMunicipal solid waste (MSW) contains mineral materials which are seldom considered as a potential resource. Currently, the waste management sector pays attention to recyclable parts, biodegradable material, waste-to-energy fraction, and residues after waste reuse and recycle. In contrast, this study focus as on the mineral matter in MSW. The aim was to analyze and discuss the sources of mineral matter in MSW, the impact which the...