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MEASUREMENT OF TEMPERATURE-DEPENDENT VISCOSITY AND THERMAL CONDUCTIVITY OF ALUMINA AND TITANIA THERMAL OIL NANOFLUIDS
PublikacjaIn this study results of simultaneous measurements of dynamic viscosity, thermal conductivity, electrical conductivity and pH of two nanofluids, i.e. thermal oil/Al2O3 and thermal oil/TiO2 are presented. Thermal oil is selected as a base liquid because of possible application in ORC systems as an intermediate heating agent. Nanoparticles were tested at the concentration of 0.1%, 1% and 5% by weight within temperature range from...
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The Taxonomy Spatial Measure of Development in the Standard of Living Analysis
PublikacjaIncorporation of spatial relationships in the construction of taxonomy measure of development is gaining popularity in Polish literature. However, there is no one common idea concerning how the spatial relationship should be taken into account when creating a synthetic variable nor, indeed, where the spatial weight matrix should be placed. It seems that the inclusion of spatial relationships is more important in smaller regions’...
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Rhodotorulic Acid and its Derivatives: Synthesis, Properties, and Applications
PublikacjaSiderophores are low molecular weight compounds produced by microorganisms to scavenge iron in iron-deficient environments. Rhodotorulic acid (RA), a natural hydroxamate siderophore, plays a vital role in iron acquisition for fungi and bacteria. As the simplest natural hydroxamate siderophore, RA exhibits a high affinity for ferric ions, enabling it to form stable complexes that facilitate iron uptake and transport within microorganisms....
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OBTAINING OF COUMARONE-INDENE RESINS BASED ON LIGHT FRACTION OF COAL TAR 3. COUMARONE-INDENE RESINS WITH METHACRYLIC FRAGMENTS
PublikacjaThe method for obtaining coumarone-indene resins with methacrylic fragments (CIRM) was developed with the addition of methyl ethacrylate, using a light fraction of coal tar and its fraction boiling within 423–463 К. CIRM was obtained via radical cooligomerization using 2,2'-azobis (2-methyl-propionitrile) as the initiator. The effect of the initiator amount, temperature and reaction time on the yield, softening temperature and...
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Hybrid Modulation for Modular Voltage Source Inverters with Coupled Reactors
PublikacjaThis paper proposes and discusses a concept of a hybrid modulation for the control of modular voltage source inverters with coupled reactors. The use of coupled reactors as the integrating elements leads to significant reduction in the size and weight of the circuit. The proposed modulation combines novel coarsely quantized pulse amplitude modulation (CQ-PAM) and innovative space-vector pulse width modulation (SVPWM). The former...
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Wpływ produkcji butelek z tworzyw sztucznych na środowisko naturalne. Cz. I. Zastosowanie metody oceny ReCiPe 2016 w celu identyfikacji problemów środowiskowych
PublikacjaDokonano oceny wpływu opakowań na środowisko naturalne. Głównym celem było przeprowadzenie analizy cyklu życia (LCA) butelki do napojów wykonanej z poli(tereftalanu etylenu) (PET). Za jednostkę funkcjonalną przyjęto łącznie 1000 szt. butelek PET o pojemności 1 L. Granica przyjętego systemu obejmowała kroki od momentu dostarczenia preform do zakładu produkcyjnego aż do ich prawidłowego ukształtowania w procesie produkcyjnym. Z systemu...
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DNA-damaging imidazoacridinone C-1311 induces autophagy followed by irreversible growth arrest and senescence in human lung cancer cells
PublikacjaImidazoacridinone 5-diethylaminoethylamino-8-hydroxyimidazoacridinone (C-1311) is an antitumor inhibitor of topoisomerase II and FMS-like tyrosine kinase 3 receptor. In this study, we describe the unique sequence of cellular responses to C-1311 in human non-small cell lung cancer (NSCLC) cell lines, A549 and H460. In A549 cells, C-1311 (IC80 = 0.08 µM) induced G1 and G2/M arrests, whereas H460 cells (IC80 = 0.051 µM) accumulated...
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Exploring the Antitumor Efficacy of N-Heterocyclic Nitrilotriacetate Oxidovanadium(IV) Salts on Prostate and Breast Cancer Cells
PublikacjaThe crystal structures of two newly synthesized nitrilotriacetate oxidovanadium(IV) salts, namely [QH][VO(nta)(H2O)](H2O)2 (I) and [(acr)H][VO(nta)(H2O)](H2O)2 (II), were determined. Additionally, the cytotoxic effects of four N-heterocyclic nitrilotriacetate oxidovanadium(IV) salts— 1,10-phenanthrolinium, [(phen)H][VO(nta)(H2O)](H2O)0.5 (III), 2,2′-bipyridinium [(bpy)H][VO(nta)(H2O)](H2O) (IV), and two newly synthesized compounds...
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A facile strategy for reclaiming discarded graphite and harnessing the rate capabilities of graphite anodes
PublikacjaGraphite negative electrodes are unbeaten hitherto in lithium-ion batteries (LiBs) due to their unique chemical and physical properties. Thus, the increasing scarcity of graphite resources makes smart recycling or repurposing of discarded graphite particularly imperative. However, the current recycling techniques still need to be improved upon with urgency. Herein a facile and efficient hydrometallurgical process is reported to...
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Highly Dissipative Materials for Damage Protection against Earthquake-Induced Structural Pounding
PublikacjaIt is a common situation that seismic excitations may lead to collisions between adjacent civil engineering structures. This phenomenon, called earthquake-induced structural pounding, may result in serious damage or even the total collapse of the colliding structures. Filling the gap between two buildings erected close to one another by using visco-elastic materials can be considered to be one of the most effective methods to avoid...
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In vivo imaging of the human eye using a two-photon excited fluorescence scanning laser ophthalmoscope
PublikacjaBACKGROUND. Noninvasive assessment of metabolic processes that sustain regeneration of human retinal visual pigments (visual cycle) is essential to improve ophthalmic diagnostics and to accelerate development of new treatments to counter retinal diseases. Fluorescent vitamin A derivatives, which are the chemical intermediates of these processes, are highly sensitive to UV light; thus, safe analyses of these processes in humans...
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On design and analysis of flow characteristics of the last stage of gas-steam turbine
PublikacjaResearch regarding blade design and analysis of flow have been conducted for over a century. Meanwhile new concepts and design approaches were created and improved. Advancements in information technologies allowed to introduce computational fluid dynamics (CFD) and computational flow mechanics (CFM). Currently a combination of mentioned methods is used for design of turbine blades. These methods enabled us to improve flow efficiency...
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Self-Optimizing Adaptive Vibration Controller
PublikacjaThis paper presents a new approach to rejection of sinusoidal disturbances acting at the output of a discrete-time linear stable plant with unknown dynamics. It is assumed that the frequency of the sinusoidal disturbance is known, and that the output signal is contaminated with wideband measurement noise. The proposed controller, called SONIC (self-optimizing narrowband interference canceller), combines the coefficient fixing technique,...
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A new approach to active noise and vibration control - [Part I: the known frequency case]
PublikacjaThis paper presents a new approach to rejection of complex-valued sinusoidal disturbances acting at the output of a discrete-time stable linear plant with unknown dynamics. It is assumed that the frequency of the sinusoidal disturbance is known, and that the output signal is contaminated with wideband measurement noise. The disturbance rejection control rule is first derived and analyzed for a nominal plant model, different from...
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An Empirical Model for the Polarisation Characteristics of Indoor Off-Body Channels
PublikacjaThis paper presents an analysis of the polarisation characteristics for the channel in dynamic off-body communications, and an empirical channel model, based on measurements performed at 2.45 GHz in an office environment. Body presence and propagation conditions have a strong influence on signal depolarisation. The model assumes three components for the total path loss: mean path loss, represented by a log-distance function with...
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Weak Stability of Centred Quadratic Stochastic Operators
PublikacjaWe consider the weak convergence of iterates of so-called centred quadratic stochastic operators. These iterations allow us to study the discrete time evolution of probability distributions of vector-valued traits in populations of inbreeding or hermaphroditic species, whenever the offspring’s trait is equal to an additively perturbed arithmetic mean of the parents’ traits. It is shown that for the existence of a weak limit, it...
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High-temperature kinetics study of 430L steel powder oxidized in air at 600–850 °C
PublikacjaThe 430L stainless steel powder with a mean particle size of 95 μm was studied to determine its high-temperature oxidation properties. Continuous thermogravimetric measurements were carried out for 100 h in air at temperatures in the range of 600–850 °C. Even though a considerable amount of Cr (up to ˜5 wt.% Cr) inside the grains was depleted – especially inside small grains – no breakaway oxidation was observed. This indicates...
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Wideband Off-Body Channel Characteristics with Dynamic User
PublikacjaThis paper presents the preliminary results of a dynamic off-body channel characterisation study, based on wideband measurements at 5.8 GHz in an indoor environment. The Channel Impulse Response (CIR) was measured for a scenario with the user approaching and departing from the off-body antenna. A CIR deconvolution procedure was performed jointly in two polarisations, and the received signal power, Cross-Polarisation Discrimination...
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Minimal surfaces and conservation laws for bidimensional structures
PublikacjaWe discuss conservation laws for thin structures which could be modeled as a material minimal surface, i.e., a surface with zero mean curvatures. The models of an elastic membrane and micropolar (six-parameter) shell undergoing finite deformations are considered. We show that for a minimal surface, it is possible to formulate a conservation law similar to three-dimensional non-linear elasticity. It brings us a path-independent...
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Regression points in non-intrusive polynomial chaos expansion method and D-optimal design
PublikacjaThe paper addresses selected issues of uncertainty quantification in the modelling of a system containing surgical mesh used in ventral hernia repair. Uncertainties in the models occur e.g. due to variability of abdominal wall properties among others. In order to include them, a non-intrusive regression-based polynomial chaos expansion method is employed. Its accuracy depends on the choice of regression points. In the study a relation...
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The study of acoustic climate of the Southern Baltic
PublikacjaThis paper presents the statistical characteristics of seawater properties, which are necessary for predicting the propagation of acoustic waves in selected areas of the Baltic Sea. The statistics were elaborated based on long-term measurements of vertical distributions of sound speed, temperature, and salinity, and the nonlinearity parameter B/A. Nonlinear properties of the environment are considered, in connection...
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Ultrasound monitoring for evaluation of damage in reinforced concrete
PublikacjaThe paper deals with automated monitoring of damage evolution in concrete elements subjected to three-point bending tests. The monitoring is based on the nonlinear interactions of traveling ultrasonic waves with micro-crack zones inside the concrete specimens and surface-breaking cracks. The developed procedure assumes semi-continuous ultrasonic testing during the element full loading cycle and generation of the power spectral...
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A multistage turbine for a micro power plant
PublikacjaThis paper presents results of a design analysis of a multi-stage turbine for the cogeneration micro-power plant working in accordance with Organic Rankine Cycle (ORC). The heat power of the plant is assumed equal to 20 kW and the corresponding available electric output is estimated to be of about 3 kW. Different variants of the radial and axial-flow turbines have been considered, while the detailed results of the calculations...
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Mercury in Living Organisms: Sources and Forms of Occurrence, Bioaccumulation, and Determination Methods
PublikacjaMercury (Hg) is a heavy metal with well-known and broadly tested toxicity. Since Hg pollution and its impacts on human health are of global concern, it has become necessary to develop analytical methodologies that will provide tools to obtain reliable analytical information about the levels of Hg in samples, which very often have a complex matrix composition. This chapter summarizes key information on Hg and its chemical forms,...
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Bi-GRU-APSO: Bi-Directional Gated Recurrent Unit with Adaptive Particle Swarm Optimization Algorithm for Sales Forecasting in Multi-Channel Retail
PublikacjaIn the present scenario, retail sales forecasting has a great significance in E-commerce companies. The precise retail sales forecasting enhances the business decision making, storage management, and product sales. Inaccurate retail sales forecasting can decrease customer satisfaction, inventory shortages, product backlog, and unsatisfied customer demands. In order to obtain a better retail sales forecasting, deep learning models...
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Self-assessment of competencies of students and graduates participating in didactic projects – Case study
PublikacjaAim/purpose: the aim of this article is to examine the opinions of students and graduates of the faculty of economics of a technical university as regards their selfassessment of their preparation for entering the modern labour market. All the respondents participated during their studies in didactic projects aimed at improving their competencies taking into account the expectations of potential employers. Design/methodology/approach:...
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ARIMA vs LSTM on NASDAQ stock exchange data
PublikacjaThis study compares the results of two completely different models: statistical one (ARIMA) and deep learning one (LSTM) based on a chosen set of NASDAQ data. Both models are used to predict daily or monthly average prices of chosen companies listed on the NASDAQ stock exchange. Research shows which model performs better in terms of the chosen input data, parameters and number of features. The chosen models were compared using...
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The correlation of fractal dimension to fracture surface slope for fatigue crack initiation analysis under bending-torsion loading in high-strength steels
PublikacjaIn this study, the fractal dimension of fatigue fracture surfaces is investigated in order to find an alternative failure loading indicator. Some of many metrological factors are generalized by reducing the fracture surface structure to one factor and develop an entire fracture surface procedure by analyzing the impact of surface slope and calculation resolution. Three notched geometries are studied under cyclic bending-torsion:...
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Computational Complexity and Its Influence on Predictive Capabilities of Machine Learning Models for Concrete Mix Design
PublikacjaThe design of concrete mixtures is crucial in concrete technology, aiming to produce concrete that meets specific quality and performance criteria. Modern standards require not only strength but also eco-friendliness and production efficiency. Based on the Three Equation Method, conventional mix design methods involve analytical and laboratory procedures but are insufficient for contemporary concrete technology, leading to overengineering...
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Effective Air Quality Prediction Using Reinforced Swarm Optimization and Bi-Directional Gated Recurrent Unit
PublikacjaIn the present scenario, air quality prediction (AQP) is a complex task due to high variability, volatility, and dynamic nature in space and time of particulates and pollutants. Recently, several nations have had poor air quality due to the high emission of particulate matter (PM2.5) that affects human health conditions, especially in urban areas. In this research, a new optimization-based regression model was implemented for effective...
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Measured and predicted freeze-thaw days frequencies in climate change conditions in central Poland
PublikacjaThe rate of progression of geomorphological phenomena is greatly influenced by freeze-thaw processes. In the face of air temperature increasing over the past few decades, a question of the future impact of these processes arises, notably in the temperate and cold climate zones. Using the mean, maximum and minimum daily air temperature data in the period 1951–2018 obtained from three weather stations located in the vicinity of Jeziorsko...
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Comparative study on total nitrogen prediction in wastewater treatment 1 plant and effect of various feature selection methods on machine learning algorithms performance
PublikacjaWastewater characteristics prediction in wastewater treatment plants (WWTPs) is valuable and can reduce the number of sampling, energy, and cost. Feature Selection (FS) methods are used in the pre-processing section for enhancing the model performance. This study aims to evaluate the effect of seven different FS methods (filter, wrapper, and embedded methods) on enhancing the prediction accuracy for total nitrogen (TN) in the WWTP...
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A Comparability of Renal Length and Volume Measurements in MRI and Ultrasound in Children
PublikacjaIntroduction: Despite the significant increase in use of magnetic resonance imaging (MRI) in children, there is still a lack of normal reference values of renal size in this method and reference values are being interpolated from the ultrasound (US) studies. The study provides comparative analysis of agreement in renal length and volume measurements between MRI and ultrasound. Materials and Methods: Ninety-three children with a...
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Preliminary studies of seamless flux cored wires stored in extreme conditions
PublikacjaIn the paper preliminary experimental studies of flux cored wires moisturized under controlled conditions are described. Three seamless wires of different grades have been placed in environmental chamber and moisturized in extremely adverse conditions (temperature T = 60° C, relative humidity H = 90%) for 240 hours. During this time measurements of weight gain and observations of surface of wires have been carried out. Also diffusible...
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Synthetic Principles Determining Local Organization of Copolyesters Prepared from Lactones and Macrolactones
PublikacjaA highly effective and facile technique for catalytic ring-opening copolymerization (cROP) of lactones viz. ε- caprolactone and ε-decalactone with ω-pentadecalactone is being described. The reactions were mediated by Zn- and Cabased tridentate Schiff base complexes and benzyl alcohol as initiator. The catalysts were successfully employed for the preparation of numerous block and random copolymers. To unravel the composition of...
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Examining Ownership Equity as a Psychological Factor on Tourism Business Failure Forecasting
PublikacjaThis paper examines ownership equity as a predictor of future business failure within the tourism and hospitality sectors. The main goals of this study were to examine which ratios are the most important for a tourism business failure forecasting model and how significant is the “total percentage of equity ownership by company directors” ratio compared with other ratios associated with the probability of bankruptcy. A stepwise...
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Outlier detection method by using deep neural networks
PublikacjaDetecting outliers in the data set is quite important for building effective predictive models. Consistent prediction can not be made through models created with data sets containing outliers, or robust models can not be created. In such cases, it may be possible to exclude observations that are determined to be outlier from the data set, or to assign less weight to these points of observation than to other points of observation....
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Sessile droplet contact angle of water–Al2O3, water–TiO2 and water–Cu nanofluids
PublikacjaThis work presents measurements of the contact angle of sessile droplets for three nanofluids, i.e. water–Al2O3, water–TiO2 and water–Cu. The plates made of glass, anodized aluminium and stainless steel of different roughness served as substrates. Ultrasonic vibration was used for 30–60 min in order to stabilise the dispersion of the nanoparticles. Nanoparticles were tested at the concentration of 0.01%, 0.1%, and 1% by weight....
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On ''cheap smoothing'' opportunities in identification of time-varying systems
PublikacjaIn certain applications of nonstationary system identification the model-based decisions can be postponed, i.e. executed with a delay. This allows one to incorporate into the identification process not only the currently available information, but also a number of ''future'' data points. The resulting estimation schemes, which involve smoothing, are not causal. Despite the possible performance improvements, the existing smoothing...
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Module architecture as alternative approach to traditional construction processes
PublikacjaModule architecture today is a special type of building construction process that combines repetitive design, low-cost production based on prefabricated elements and fast erection. Module does not mean the same as modular. In general, module architecture today refers to the design of any system composed of separate components, manufactured before in factory, that can be connected together at the building site much faster than normally....
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Study of the atomic structure and morphology of the Pt3Co nanocatalyst
PublikacjaThe local structure and chemical disorder of a commercially available Pt3Co nanocatalyst supported on high surface area carbon were investigated. High-quality XAFS spectra were collected at the ELETTRA synchrotron XAFS 11.1 beamline. XAFS spectra analysis have been performed accounting for the reduction of the coordination number and degeneracy of three-body configurations, resulting from transmission electron microscopy (TEM)...
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On Anti-Plane Surface Waves Considering Highly Anisotropic Surface Elasticity Constitutive Relations
PublikacjaWithin the framework of highly anisotropic surface elasticity model we discuss the propagation of new type of surface waves that are anti-plane surface waves. By the highly anisotropic surface elasticity model we mean the model with a surface strain energy density which depends on incomplete set of second derivatives of displacements. From the physical point of view this model corresponds to a coating made of a family of parallel...
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System Loss Model for Body-to-Body Networks in Indoor and Outdoor Environments
PublikacjaA system loss model for body-to-body networks in indoor and outdoor environments is proposed in this paper, based on measurements taken at 2.45 GHz. The influence of the type of environment, antenna visibility and user mobility on model parameters has been investigated. A significant impact of mutual antennas’ placement and their visibility is shown. The proposed model fits well to empirical data, with the average root mean square...
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Comparative analysis of numerical with optical soliton solutions of stochastic Gross–Pitaevskii equation in dispersive media
PublikacjaThis article deals with the stochastic Gross–Pitaevskii equation (SGPE) perturbed with multiplicative time noise. The numerical solutions of the governing model are carried out with the proposed stochastic non-standard finite difference (SNSFD) scheme. The stability of the scheme is proved by using the Von-Neumann criteria and the consistency is shown in the mean square sense. To seek exact solutions, we applied the Sardar subequation...
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RMS-based damage detection in reinforced concrete beams: numerical simulations
PublikacjaImage-based damage detection methods using guided waves are well known and widely applied approaches in structural diagnostics. They are usually utilized in detection of surface damages or defects of plate-like structures. The article presents results of the study of applicability of imaging wave-based methods in detection in miniscule internal damage in the form of debonding. The investigations were carried out on numerical models...
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Selected Aspects of Pavement Texture Influence on Tire Rolling Resistance
PublikacjaTire rolling resistance has a significant influence on fuel consumption in cars and trucks and on CO2 emissions. Rolling resistance depends on the tire construction, pavement texture and stiffness, as well as environmental and traffic conditions. This article presents a pilot study on the impact of pavement texture on the rolling resistance of passenger car tires. Reasons why Mean Profile Depth is not a good descriptor of pavement...
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Organomercury compounds in environmental samples: emission sources, toxicity, environmental fate and determination.
PublikacjaIn view of the specific properties of mercury and its capability of forming compounds that can be bioaccumulated and biomagnified at successive levels of the trophic pyramid, it has become necessary to gather detailed information on the sources of emission of this element into the environment and its fate there. Moreover, the increasing awareness of the relationship between the toxicity of mercury and its chemical form has sharpened...
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Gas boiler as a heat source for the domestic micro-CHP
PublikacjaThis analysis considers a commercially available domestic gas boiler as a heat source for a domestic organic Rankine cycle system. An experimental study was made into the applicability of the gas boiler (De Dietrich with thermal power 25 kW) coupled with the laboratory prototype micro ORC setup. The main aim of the study is to determine the working fluid temperature, attainable heat rates and effciencies of the whole system. Preliminary...
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The Effect of Water and Frost on Fatigue Life of Asphalt Concrete
PublikacjaThis paper presents testing of fatigue life of asphalt concrete that has been subjected to action of water and frost. Simulation of water and frost action was based on the original AASHTO T283 method and its modification. The original method was modified in such a way that instead of a single freeze-thaw cycle, 50 and 150 cycles were applied. Fatigue life was measured in the indirect tensile fatigue test in the Nottingham asphalt...
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Small Scale Gasification of Biomass and Municipal Wastes for Heat and Electricity Production using HTAG Technology
PublikacjaCombustion and gasification technology utilizing high-cycle regenerative air/steam preheater has drawn increased attention in many application areas. The process is to be realized at temperature level above ash melting point using highly preheated agent. The use of highly preheated media above 900degC provides additional energy to conversion processes and results in considerable...