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Comparative evaluation of different methods for determining phytochemicals and antioxidant activity in products containing betalains - Verification of beetroot samples
PublikacjaThis study presents methods that can be used to assess the health quality of products containing betalains. The paper compares and verifies data on the phytochemical composition of three different pigmented beetroot cultivars using spectrophotometric, HPLC-DAD, HPTLC and LC-Q-Orbitrap-HRMS techniques. Additionally, we compared the total antioxidant activity in both the cell-free and cellular systems. Betalain contribution to antioxidant...
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The roadway bridge over Vistula River in Plock - design and construction.
PublikacjaThe paper presents the design and construction works of the Roadway Bridge over Vistula River in Plock (Poland), designed by first two paper authors as being the winners of international competition for design oraganized by Polish association of the bridge engineers. Total length of the bridge is 1,200 m; 615 m is the length of main bridge part over the Vistula riverbed, and 585 m is the length of access bridge part over river...
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Experimental and numerical studies on the mechanical response of a piezoelectric nanocomposite-based functionally graded materials
PublikacjaThis work presents an experimental study of piezoelectric structures reinforced by graphene platelets, based on the concept of the functionally graded materials (FGMs). The assumed model is a rectangular beam/plate and the composition is due to the Halpin-Tsai rule. The model is also simulated in the Abaqus software which is the first time that such a structure has been modelled in an FEM package. In addition, a mathematical model...
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Estimation of the Ultimate Strength of FRP Strips-to-Masonry Substrates Bond
PublikacjaFiber-Reinforced Polymers (FRP) were developed as a new method over the past decades due to their many beneficial mechanical properties, and they are commonly applied to strengthen masonry structures. In this paper, the Artificial Neural Network (ANN), K-fold Cross-Validation (KFCV) technique, Multivariate Adaptive Regression Spline (MARS) method, and M5 Model Tree (M5MT) method were utilized to predict the ultimate strength of...
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Experimental and numerical evaluation of mechanical behaviour of composite structural insulated panels
PublikacjaComposite structural insulated panels (CSIPs) are novel prefabricated elements for structural applications. Panels under consideration are made from glass-fibre reinforced magnesia cement boards as facesheets and expanded polystyrene foam (EPS) as a core. Quasi-static full-scale and model bending tests under monotonic loading were performed to recognize mechanical properties of CSIPs in flexure. In addition, tensile, compressive,...
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Ubiquity of client access in heterogeneous access environment
PublikacjaWith popularization of mobile computing and diverse offer of mobile devices providing functionality comparable to stationary computers, the necessity of providing network access for such users cannot be disputed. The requirement is further reinforced by emergence of general purpose mobile operating systems which provide their full functionality only with network connectivity available and popular XaaS (Anything as a Service) approach....
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Nonlinear Viscoelastic Properties of Polyurethane Nanocomposites
PublikacjaIn recent years, the nonlinear viscoelastic behaviors of elastomeric nanocomposites have been examined, especially for a wide range of rubbery composite (including natural rubber) materials. This chapter describes the influence of fillers and nanofillers on the nonlinear viscoelastic properties of elastomeric polyurethane systems. These filled elastomers (similar to the classic natural rubber reinforced elastomers), also exhibit...
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Nośność konstrukcji gruntowo-łukowej prefabrykowanego wiaduktu w świetle obliczeń numerycznych i badań „in situ”
PublikacjaWartykule przedstawiono analizy przeprowadzone dla wiaduktu WK-15 Pomorskiej Kolei Metropolitalnej wykonanego w technologii łuków prefabrykowanych przykrytych gruntem (system TechSpan). W celu weryfikacji obliczeń numerycznych wykonano próbne obciążenie konstrukcji. Przedstawiono wyniki pomiarów naprężeń i prezmieszczeń konstrukcji. Odniesiono się krytycznie do zastosowanego modelu obliczeniowego.
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Lightweight structures in architecture: scenarios for the future
PublikacjaLightweight structures - structures with a reduced weight, which otherwise retain the qualities necessary for the building performance, ensuring a proper durability and strength, safety, indoor environmental quality and energy efficiency; stuctures which strive for the optimization of structural systems - are in tune with current trends and socio-economic, environmental and technological factors. The growing interest in the lightweight...
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Noise Analysis of Continuous GPS Time Series of Selected EPN Stations to Investigate Variations in Stability of Monument Types
PublikacjaThe type of monument that a GPS antenna is placed on plays a significant role in noise estimation for each permanent GPS station. In this research 18 Polish permanent GPS stations that belong to the EPN (EUREF Permanent Network) were analyzed using Maximum Likelihood Estimation (MLE). The antennae of Polish EPN stations are placed on roofs of buildings or on concrete pillars. The analyzed data covers a period of 5 years from 2008...
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ZAAWANSOWANE SYMULACJE NUMERYCZNE MES DYNAMIKI MOSTÓW Z WYKORZYSTANIEM PROCEDURY EXPLICITE
PublikacjaDostęp do mocy obliczeniowej superkomputerów oraz możliwość wykorzystania nowoczesnych systemów, np. takich jak Ls-Dyna, pozwala na uzyskanie niezwykle szczegółowych rozwiązań bardzo skomplikowanych problemów inżynierskich. Zagadnienia te dotyczą zakresu statyki/stateczności jak i dynamiki dla rozbudowanych układów konstrukcyjnych zarówno w zakresie nieliniowości materiałowej jak i geometrycznej. Uzyskanie wiarygodnych wyników...
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O obliczaniu kablobetonowych ciągłych dźwigarów mostowych
PublikacjaPrzedstawiono analityczną metodę obliczania kablobetonowych ciągłych dźwigarów z wykorzystaniem metody sił. Podano przykład analizy zrealizowanego kablobetonowego wiaduktu o schemacie dwuprzęsłowej belki ciągłej. Porównano wyniki obliczeń analitycznych i numerycznych (model belkowy, program Sofistik).
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Modelling and Analysis of the Positioning Accuracy in the Loading Systems of Mobile Cranes
PublikacjaIn this work, the authors analyse the influence of the order and range of sequential movements of a crane's working members on the accuracy of the final cargo positioning. The analysis was conducted on the basis of a specially developed method in which the authors proposed the introduction of a geometrical indicator of positioning the load in the intermediate positions (after completing each movement sequence) and in the target...
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The influence of sterilization with EnbioJet Microwave Flow Pasteurizer on composition and bioactivity of aronia and blue-berried honeysuckle juices
PublikacjaIn this study, fruit juices that are rich sources of anthocyanins, obtained from aronia (Am. chokeberry, Aronia melanocarpa) and blueberry honeysuckle (Lonicera caerulea L. var. edulis) were used to examine the preservation of plant phytochemicals and bioactivity upon sterilization -either thermal, or with an EnbioJet microwave flow pasteurizer. The chemical properties verified included determinations of anthocyanins and other...
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Image Segmentation of MRI image for Brain Tumor Detection
Publikacjathis research work presents a new technique for brain tumor detection by the combination of Watershed algorithm with Fuzzy K-means and Fuzzy C-means (KIFCM) clustering. The MATLAB based proposed simulation model is used to improve the computational simplicity, noise sensitivities, and accuracy rate of segmentation, detection and extraction from MR...
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Engineering Challenges in the Design of Cochlear Implants
PublikacjaHearing aids such as cochlear implants have been used by both adults and children for a long time. In addition, cochlear implants are used by patients who have severe hearing loss either by birth or after an accident. This paper aims to investigate the engineering challenges bounding the design of cochlear implants and present its possible solution...
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Comprehensive determination of flavouring additives and nicotine in e-cigarette refill solutions. Part I: Liquid chromatography-tandem mass spectrometry analysis
PublikacjaLiquid chromatography-tandem mass spectrometry with electrospray ionization (HPLC-ESI–MS/MS) methods were developed for the simultaneous determination of 42 flavouring compounds and nicotine in liquids for e-cigarettes. The chromatographic separation was performed using an Ace® Ultracore™ SuperC18™ (100 × 2.1 mm, 2.5 μm) column in both acidic and alkaline pH conditions to separate all the compounds. A simple “dilute & shoot” approach...
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Recent Achievements in Constitutive Equations of Laminates and Functionally Graded Structures Formulated in the Resultant Nonlinear Shell Theory
PublikacjaThe development of constitutive equations formulated in the resultant nonlinear shell theory is presented. The specific features of the present shell theory are drilling rotation naturally included in the formulation and asymmetric measures of strains and stress resultants. The special attention in the chapter is given to recent achievements: progressive failure analysis of laminated shells and elastoplastic constitutive relation...
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Wave propagation in damage assessment of ground anchors
PublikacjaThe inspection possibilities of ground anchors are limited to destructive test such as pull-out test. Guided wave propagation gives an opportunity to develop an inspection system dedicated to determine the condition of inspected element without violation of their integrity. In this paper the experimental study on wave propagation in laboratory models of ground anchors are presented. Experiments were conducted for different bonding...
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Methods of estimating the cost of traffic safety equipment’s life cycle
Publikacjan the article, the authors discuss the preliminary information necessary to determine the scope and direction of further research conducted within the project called “The influence of time and operating conditions on the durability and functionality of road safety elements”. The main objective of the project is to develop the concept of a method for optimizing the life cycle costs of road safety devices. The authors draw attention...
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Analysis of load carrying capacity and destruction mechanism of an intermediate anchorage steel plate for pillar jib crane
PublikacjaPillar jib cranes are often mounted to existing floors with the use of an intermediate anchorage steel plate instead of using independent foundations, what is shown in the figure. Standards for steel design provide only basic rules for the design of such an intermediate plate. This study presents a simple design approach by using a numerical model in order to analyze different parameters that have significant influence in the anchorage...
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Mechanical, thermo-mechanical properties of epoxy/glass composites with submicron particles
PublikacjaIn this research the influence of submicron zinc oxide and silicon dioxide particles on mechanical, thermo-mechanical properties of epoxy matrix composites reinforced with glass fibres was investigated. Composites were fabricated using hand lay-up method. Materials contained 39-41 wt.% of glass fibres. The bending tests, dynamic mechanical analysis and tribological tests were performed on each group of composites and also for...
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Impact resistance of plain and twill fabric in GFRP measured by active thermography
PublikacjaThis paper discusses the impact resistance of glass-fibre reinforced polymer (GFRP) composites depending on the type of reinforcement – plain or twill weave. The values of impact energy were: 3J, 10J and 15J. Specimens featuring twill weave transferred higher force during the impact as compared with plain weave specimens. It was observed that an increase of impact energy was accompanied by an increase of the disproportion in...
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A survey of strategies for communication networks to protect against large-scale natural disasters
PublikacjaRecent natural disasters have revealed that emergency networks presently cannot disseminate the necessary disaster information, making it difficult to deploy and coordinate relief operations. These disasters have reinforced the knowledge that telecommunication networks constitute a critical infrastructure of our society, and the urgency in establishing protection mechanisms against disaster-based disruptions. Hence, it is important...
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Dynamic tests of composite footbridge segment – experimental and numerical studies
PublikacjaExperimental dynamic tests and numerical simulations of a 3 meters long segment of a footbridge made of polymer composites are presented in the paper. The span-length is reduced, however dimensions of cross-section are the same as the target footbridge. The segment structure is made of sandwich panels, which consist of fibre reinforced polymer (GFRP) laminates (skins) and a PET foam (core). The first part of the paper contains...
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Sensitivity analysis of free torsional vibration frequencies of thin-walled laminated beams under axial load
PublikacjaThe paper addresses sensitivity analysis of free torsional vibration frequencies of thin-walled beams of bisymmetric open cross-section made of unidirectional fibre-reinforced laminate. The warping effect and the axial end load are taken into account. The consideration is based upon the classical theory of thin-walled beams of non-deformable cross-section. The first-order sensitivity variation of the frequencies is derived with...
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Strongly anisotropic surface elasticity and antiplane surface waves
PublikacjaWithin the new model of surface elasticity, the propagation of anti-plane surface waves is discussed. For the proposed model, the surface strain energy depends on surface stretching and on changing of curvature along a preferred direction. From the continuum mechanics point of view, the model describes finite deformations of an elastic solid with an elastic membrane attached on its boundary reinforced by a family of aligned elastic...
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Composites in energy storing prosthetic feet
PublikacjaComposites reinforced with carbon and glass fibers have become the commonly used material in the production of energy storing prosthetic feet (ESPF/elastic feet prostheses). Their properties ensure a stable and light structure that allows for accumulation, storage and release of energy during walking, thus ensuring an increase in gait efficiency. Depending on the modification of the composite in terms of fiber selection, their...
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Short and Long Term Measurements in Assessment of FRP Composite Footbridge Behavior
PublikacjaThe paper presents application of different sensors for the purpose of short and long term measurements, as well as a structural health monitoring (SHM) system to assess the behavior of a novel fiber reinforced plastics (FRP) composite footbridge. The aim is to present a thorough and concise description of these sensors networks and results gathered with their aid during in situ measurement of strains, displacements, and vibrations,...
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Parametric analysis of Istanbul's Ring Road viaduct for three levels of seismic load
PublikacjaThe paper presents a parametric analysis of the Istanbul's ring road viaduct that is currently under construction within the Northern Marmara Highway project. The structure, due to its location on seismic prone areas is exposed to seismic loads of different strengths and different return periods. The study is focused on concrete bridge supports that are design to work in nonlinear range. The parametric study, conducted in MATLAB...
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Modelling the malware propagation in mobile computer devices
PublikacjaNowadays malware is a major threat to the security of cyber activities. The rapid develop- ment of the Internet and the progressive implementation of the Internet of Things (IoT) increase the security needs of networks. This research presents a theoretical model of malware propagation for mobile computer devices. It is based on the susceptible-exposed- infected-recovered-susceptible (SEIRS) epidemic model. The scheme is based on...
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Improvement of the load capacity of the road overpass as a result of repairs after breakage caused by vehicle impacts
PublikacjaDamage of spans of the overpass caused by impact of underpassing vehicles are a frequent case. Objects that use prefabricated load-bearing elements that are not designed for such impacts are particularly exposed. After impact, such parts suffer extensive damage that need repair. Taking advantages of this recovery actions it is worth to perform strengthening that will protect object against possible future impacts. In this study...
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WYKORZYSTANIE SIECI NEURONOWYCH DO SYNTEZY MOWY WYRAŻAJĄCEJ EMOCJE
PublikacjaW niniejszym artykule przedstawiono analizę rozwiązań do rozpoznawania emocji opartych na mowie i możliwości ich wykorzystania w syntezie mowy z emocjami, wykorzystując do tego celu sieci neuronowe. Przedstawiono aktualne rozwiązania dotyczące rozpoznawania emocji w mowie i metod syntezy mowy za pomocą sieci neuronowych. Obecnie obserwuje się znaczny wzrost zainteresowania i wykorzystania uczenia głębokiego w aplikacjach związanych...
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The effect of road restraint systems on the level of road safety - Polish experience
PublikacjaRoadside accidents happen when a vehicle runs off the road. The majority of these accidents are very severe because leaving the road is usually followed by hitting a solid obstacle (tree, pole, support, culvert front wall, barrier). Roadsides are some of the most important issues of road safety. They have been studied for years to identify roadside hazards and the effectiveness of road safety measures such as restraint systems....
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Timber - material of the future. Examples of small wooden architecture structures.
PublikacjaThe aim of this article is to present various types of wood-based products, classified as engineered timber, while specifying the implications of their structural properties for their forms. Timber is used as a construction material due to its fire resistance, good structural characteristics and insulating properties. The advent of new technologies of wood processing and wood-based materials production has converted timber into...
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Determination of Selected Organic Acids in Animal Farm Water Samples by Ion Chromatography
PublikacjaLow 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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Gentiana asclepiadea exerts antioxidant activity and enhances DNA repair of hydrogen peroxide- and silver nanoparticles-induced DNA damage
PublikacjaExposure to high levels of different environmental pollutants is known to be associated with induction of DNA damage in humans. Thus DNA repair is of great importance in preventing mutations and contributes crucially to the prevention of cancer. In our study we have focused on quantitative analysis of Gentiana asclepiadea aqueous or methanolic extracts obtained from flower and haulm, their antioxidant potency in ABTS post-column...
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Photovoltaic Maximum Power Point Technique based on Incremental Conductance (INCON) control algorithm
PublikacjaMaximum output power status can significantly improve the deployment rate of solar energy system. In order to get the maximum power output, issue of tracking maximum power point (MPP), reduced harmonics around MPP and improve efficiency of the solar power energy system, this paper presents the improved maximum power point tracking (MPPT) control...
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Maximum Power Point Technique (MPPT) for PV System Based on Improved Pert and Observe (P&O) Method with PI Controller
PublikacjaPhotovoltaic power generation system has key rule in electricity production. Although, it is clean renewable energy with unlimited resources but it has some drawbacks in efficiency. In order to maximize the efficiency, PV array must drive at maximum power point. For the reason so, several algorithms are used in PV system to track MPP and reduce the...
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The influence of roasting and additional processing on the content of bioactive components in special purpose coffees
PublikacjaCoffee being the beverage consumed worldwide is also a very competitive commodity. Consequently, producers seek ways of attracting consumers by proposing e.g. novel ingredient combinations usually without evaluating their health quality. In this study, variations in health-promoting determinants for five special purpose coffee brews were characterized. The major bioactive components - chlorogenic acids (CAs) - detected by HPLC-DAD-MS...
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Polycyclic aromatic hydrocarbons as test probes to investigate the retention behavior of 1,3-alternate calix[4]arene silica-bonded stationary phases
PublikacjaA series of polycyclic aromatic hydrocarbons (PAHs) of different size and shape has been used to characterize the chromatographic behavior of five calix[4]arene stationary phases in 1,3-alternate conformation synthesized in our laboratory. The selection of linear, fourring nonlinear, and five-ring PAHs gave data on selectivity changes across range of the calix[4]arene columns. Retention of the 12 aromatic solutes has been evaluated...
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Levels of 13 multi-class pesticide residues in Polish honeys determined by LC-ESI-MS/MS
PublikacjaLevels of 13 pesticides in 40 honey samples form Poland are reported. A rapid and sensitive method was developed for the LC-ESI-MS/MS determination of multi-class pesticide residues in honey samples. Liquid-liquid extraction (LLE) on a diatomaceous earth support (requiring the use of small amounts of organic solvent), followed by chromatographic separation on a C18 column and gradient elution were employed. The method quantifies...
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Chemical composition of shells from red (Strongylocentrotus franciscanum) and green (Strongylocentrotus droeba-chiensis) sea urchin
PublikacjaThe shells from red and green sea urchins accounted for 47.9 and 40.7% of their body weights, respectively. The red and green sea urchin shells contained 91.08 and 90.77% minerals and 4.06 and 4.99% proteins, respectively. The shells did not contain any chitin. Sea urchin shells had a relatively large amount of naphthoquinone pigments, 121 mg per 100 g in red and 163 mg per 100 g in green species. The small quantities of glucosamine...
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Assessment of Lipophilicity Indices Derived from Retention Behavior of Antioxidant Compounds in RP-HPLC
PublikacjaReverse phase high pressure liquid chromatography was employed in order to evaluate the lipophilicity of antioxidant compounds from different classes, such as phenolic acids, flavanones, flavanols, flavones, anthocyanins, stilbenes, xantonoids, and proanthocyanidins. The retention time of each compound was measured using five different HPLC columns: RP18 (LiChroCART, Purosphere RP-18e), C8 (Zorbax, Eclipse XDBC8), C16-Amide (Discovery...
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Determination of cyanide in urine and saliva samples by ion chromatography with pulsed amperometric detection
PublikacjaCommonly known as a highly toxic chemical, cyanide is also an essential reagent for many industrial processes. It naturally occurs in plant seeds as a cyanogenic glycosides. Another relatively common mode of cyanide exposure is inhalation of environmental tobacco smoke. This study concerns importance to determine cyanide ion in human biological samples. Urine and saliva samples were collected healthy volunteers exposed to tobacco...
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Heavy Metals in a High Arctic Fiord and Their Introduction with the Wastewater: A Case Study of Adventfjorden-Longyearbyen System, Svalbard
PublikacjaLongyearbyen is the largest settlement on Svalbard archipelago, with 2400 permanent residents and approximately 150,000 tourists visiting every year. The city annually releases approximately 285,000 m3 of untreated wastewater to the nearby Adventfjorden. To date, the environmental impact of this continuous input has been studied mainly regarding the sediments and benthic fauna in the fiord. Here, we present results from a study...
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Infiltration in a double-porosity medium: Experiments and comparison with a theoretical model
PublikacjaThis paper presents experimental verification of the mathematical model of unsaturated flow in double‐porosity soils developed by the asymptotic homogenization method. A series of one‐dimensional infiltration experiments was carried out in a column filled with a double‐porosity medium composed of a mixture of sand and sintered clayey spheres arranged in a periodic manner. The unsaturated hydraulic properties of each porous material...
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Degradation kinetics and mechanism of pentoxifylline by ultraviolet activated peroxydisulfate
PublikacjaDegradation of pentoxifylline (PTX) by sodium peroxydisulfate (SPDS) assisted by UV irradiation has been investigated in deionized water. The treatment was more favorable over direct photolysis or peroxydisulfate oxidation alone. The effects of various parameters, including different dosage of oxidant agent, PTX concentration, initial solution pH levels, and the presence of inorganic ions like chloride, nitrate and carbonate have...
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Interoperability Description of Web Services Based Application Servers
PublikacjaWeb services standards were designed to enable interoperability of heterogeneous application servers in the Service Oriented Architecture. Although the standards proved to be highly successful, there are still difficulties in effective services integration. The paper presents a methodology that enables description of application servers interoperability in order to improve the service integration process. The methodology proposes...
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Mechanical Properties of Aluminium Bracket Strengthening
PublikacjaThe aim of the research is laboratory investigation of aluminium brackets employed to fasten lightweight curtain walls to building facilities. Tensile loads perpendicular to end plates (vertical) were applied here. The author focused on the solutions intended to increase the load-carrying capacity of aluminium brackets applying the plain washer form A (DIN 125; ISO 7089), plain washer with an outer diameter about 3d (DIN 9021;...