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Modeling the Structure, Dynamics, and Transformations of Proteins with the UNRES Force Field
PublikacjaThe physics-based united-residue (UNRES) model of proteins ( www.unres.pl ) has been designed to carry out large-scale simulations of protein folding. The force field has been derived and parameterized based on the principles of statistical-mechanics, which makes it independent of structural databases and applicable to treat nonstandard situations such as, proteins that contain D-amino-acid residues. Powered by Langevin dynamics...
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THE APPLICATION OF THE MECHANOCHEMICAL SYNTHESIS FOR THE PREPARATION OF ADVANCED CERAMICS BASED ON BARIUM TITANATE
PublikacjaIn the present study, the lead-free BaTi1-xZrxO3 (for x = 0, 0.05 and 0.15) ceramics were prepared by High-Energy Ball Milling and heat treatments. The performed X-ray, SEM and EDS measurements confirmed high purity, good quality and the expected quantitative composition of the obtained samples. The study of dielectric properties was performed by means of broadband dielectric spectroscopy at the frequency ranging from 0.1 Hz to...
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Does the low optical band gap of yellow Bi3YO6 guarantee the photocatalytical activity under visible light illumination?
PublikacjaBi3YO6, which is known as an ionic conductor, was tested here as an electrode and photoanode in contact with aqueous electrolytes. Bi3YO6 was deposited onto the Pt substrate and the such prepared electrode was polarized in various aqueous electrolytes. The optical energy band gap of the material equal to 1.89 eV was determined using the Kubelka-Munk function resulting from the UV-Vis spectrum (allowed indirect transition) and also...
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Decrease in Photovoltaic Module Efficiency Due to Deposition of Pollutants
PublikacjaThe deposition of pollutants on the surface of photovoltaic (PV) modules reduce the efficiency that can be achieved in given climatic conditions. This results in the loss of energy yield obtained from the solar installation. A number of factors determine the scale of this problem. The first of these is the amount of impurities deposited, the associated amount of precipitation, and the speed and direction of the wind. A second aspect...
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A Web-GIS tool for diagnosing spatial orientation of young adults: design and evaluation of Geo-Survey
PublikacjaSpatial orientation is the effectiveness with which one is able to assess the mutual location of objects relative to a point of reference or a system of coordinates. Traditionally, this ability has been evaluated through field navigation tests, which do not take into account the prevailing influence of free online maps and virtual walks on a person’s interpretation of space. In this context, this study presents a Web-GIS tool designed...
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Constructive Controllability for Incompressible Vector Fields
PublikacjaWe give a constructive proof of a global controllability result for an autonomous system of ODEs guided by bounded locally Lipschitz and divergence free (i.e. incompressible) vector field, when the phase space is the whole Euclidean space and the vector field satisfies so-called vanishing mean drift condition. For the case when the ODE is defined over some smooth compact connected Riemannian manifold, we significantly strengthen...
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Virtual immersive environments
PublikacjaYet a higher level of active systems may be achieved when users are fully immersed in an interface which is a 3D computer generated virtual world and can interact with surrounding objects of that world as they were in a real one. This is the issue covered by Chapter 7. Interaction in such a world is both multidimensional and multimodal, with the possibility of free movement of the user in any direction and the simultaneous stimulation...
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Accuracy of marine gravimetric measurements in terms of geodetic coordinates of land reference benchmark
PublikacjaThe article presents how the values of (3D) coordinates of land reference points affect the results of gravimetric measurements made from the ship in sea areas. These measurements are the basis for 3D maritime inertial navigation, improving ships' operational safety. The campaign verifying the network absolute point coordinates used as a reference point for relative marine gravity measurements was described. The obtained values...
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Thermostability and photophysical properties of mixed-ligand carboxylate/benzimidazole Zn(II)-coordination polymers
PublikacjaThe reaction between Zn(NO3)2*6H2O or Zn(CH3COO)2*2H2O and isophthalic acid (1,3-H2bdc) in the presence of benzimidazole (Hbzim) in dimethylformamide (DMF)/ethanol (EtOH)/H2O solvent mixture at room temperature yielded two structurally different coordination polymers: [Zn2(1,3-bdc)2(Hbzim)2] (1) and [Zn2(1,3-bdc)(bzim)2] (2). (1) is a 2D-layered framework with a molecule of benzimidazole coordinated to the Zn center, whereas (2)...
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Gold(III) complexes with chloride and cyanopyridines: Facilitated hydrolysis of nitrile ligand to amide and antibacterial activity
PublikacjaA range of novel simple gold(III) compounds has been synthesized in their monocrystalline form, including two previously unknown chloro-complexes of Au3+ with 2-cyanopyridine or 3-cyanopyridine, respectively. Our investigations have revealed the intricate nature of the reaction between 2-cyanopyridine and tetrachloroauric acid, yielding at least three distinct products. The main product, obtained in high yield, is a salt featuring...
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Ordered TiO2 nanotubes with improved photoactivity through self-organizing anodization with the addition of an ionic liquid: effects of the preparation conditions
PublikacjaModifying the geometric and surface parameters of oriented TiO2 nanotubes (NTs) is beneficial to the utilization of solar energy for chemical reactions, and this performance may be further improved. Thus, the effects of adding an ionic liquid (IL), 1-butylpiridinium chloride [BPy][Cl], and the effects of the water content and preparation conditions on the surface morphological, physicochemical, photocatalytic and photoelectrochemical...
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Examining Government-Citizen Interactions on Twitter using Visual and Sentiment Analysis
PublikacjaThe goal of this paper is to propose a methodology comprising a range of visualization techniques to analyze the interactions between government and citizens on the issues of public concern taking place on Twitter, mainly through the official government or ministry accounts. The methodology addresses: 1) the level of government activity in different countries and sectors; 2) the topics that are addressed through such activities;...
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Curing epoxy resin with anhydride in the presence of halloysite nanotubes: the contradictory effects of filler concentration
PublikacjaEpoxy resins can be cured with a wide variety of curing agents such as amines and anhydrides, but anhydride curing would be more favorable for research purpose because of epoxy-anhydride curing taking place slowly at room temperature. Incorporation of natural nanosized minerals into epoxy is of environmental importance. Halloysite nanotubes (HNTs) display chemical properties similar to those of silica and alumina, and hydroxyl...
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In situ study of a composition of outlet gases from biogas fuelled Solid Oxide Fuel Cell performed by the Fourier Transform Infrared Spectroscopy
PublikacjaThe purpose of this study was to develop a method and software based on the Fourier Transform Infrared Spectroscopy for the in-situ, quantitative analysis of the composition of outlet gases from Solid Oxide Fuel Cell (SOFC). The calibration procedure performed at the beginning of the experiment indicated a polynomial dependence between the concentration of a calibrating gas (CO, CO2, CH4) and the corresponding integrated absorbance in...
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Liquefaction of alder wood as the source of renewable and sustainable polyols for preparation of polyurethane resins
PublikacjaLiquefaction of wood-based biomass gives different polyol properties depending on the reagents used. In this article, alder wood sawdust was liquefied with glycerol and poly(ethylene glycol) solvents. Liquefaction reactions were carried out at temperatures of 120, 150 and 170 °C. The obtained bio-polyols were analyzed in order to establish the process efficiency, hydroxyl number, acid value, viscosity and structural characteristics...
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Adsorption onto zeolites: molecular perspective
Publikacja2D minerals are among key elements of advanced systems, but the need for understanding their interactions/reactions with materials and systems in which they are involved necessitates tracking their molecular and atomic monitoring. Zeolitic structures are microporous materials formed in the nature through volcanic activities or synthesis. Because of their outstanding physicochemical properties like cation exchange capacity and excellent...
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Analyzing and Visualizing Government-Citizen Interactions on Twitter to Support Public Policy-making
PublikacjaTwitter is widely adopted by governments to communicate with citizens. It has become a major source of data for analyzing how governments communicate with citizens and how citizens respond to such communication, uncovering important insights about government-citizen interactions that could be used to support public policy-making. This article presents research that aims at developing a software tool called Twitter Analytics for...
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Atmospheric degradation mechanism of anthracene initiated by OH•: A DFT prediction
PublikacjaDensity functional theory (DFT) calculations at the M06-2X/def2-TZVP level have been employed to investigate the atmospheric oxidation mechanism of anthracene (ANT) initiated by HO•. Direct hydrogen atom abstraction from the ANT using HO• takes place hardly at ambient conditions while the addition of HO• to the C1, C2, and C4 sites are thermodynamically and kinetically more advantageous. The addition reactions are controlled by...
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Ionic liquid as morphology-directing agent of two-dimensional Bi2WO6: New insight into photocatalytic and antibacterial activity
PublikacjaAn efficient and durable utilization of light to drive photocatalytic reactions still requires the overcoming of barriers. Herein, two-dimensional (2D) ultrathin IL_Bi2WO6 (IL_BWO) photocatalysts were prepared for the first time via ionic liquid-assisted hydrothermal route by adjusting the amount of tetrabutylammonium chloride [TBA][Cl], synthesis temperature and duration. IL played the role of morphology-directing agent given...
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MXene-based composites for capacitive deionization – The advantages, progress, and their role in desalination - A review
PublikacjaMXenes, a novel large family of 2D transition metal carbides, carbonitrides and nitrides are currently a “hot topic” in science due to their several fascinating physical and chemical properties. It follows from a rich diversity of their elemental compositions and chemical functionalities. MXenes can form composites with many substances, including polymers or metal oxides, which allows to effective “tune” MXene characteristics to...
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Glutathione-mediated conjugation of anticancer drugs: an overview of reaction mechanisms and biological significance for drug detoxification and bioactivation.
PublikacjaThe effectiveness of many anticancer drugs depends on the creation of specific metabolites that may alter their therapeutic or toxic properties. One significant route of biotransformation is a conjugation of electrophilic compounds with reduced glutathione, which can be non-enzymatic and/or catalyzed by glutathione-dependent enzymes. Glutathione usually combines with anticancer drugs and/or their metabolites to form more polar...
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ZASTOSOWANIE APLIKACJI INTERNETOWEJ W OCENIE JAKOŚCI DOPASOWANIA APARATÓW SŁUCHOWYCH
PublikacjaW pracy opisano zastosowanie aplikacji internetowej do oceny jakości dopasowania aparatów słuchowych. Metoda oceny polega na badaniu ankietowym, uzupełnionym testem rozumienia słów jednosylabowych w polu swobodnym. Opisywana aplikacja internetowa pozwala na przeprowadzenie badania z dowolnego komputera z dostępem do sieci. Dzięki implementacji metody w postaci aplikacji internetowej, można w systematyczny i uporządkowany sposób...
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Nutraceutical value of persimmon (Diospyros kaki Thunb.) and its influence on some indices of atherosclerosis in an experiment on rats fed cholesterol-containing diet
PublikacjaThe nutraceutic value of persimmon (Diospyros kaki Thunb. cv. Triumph) and its influence on some indices of atherosclerosis were studied in vitro and in experiment on rats fed cholesterol-containing diet. It was found that persimmon possesses a high nutraceutical value: it contains soluble fibers, total polyphenols and phe - nolic acids. The content of dietary fiberwas 1.83 ± 0.11, 0.69 ± 0.07 and 1.14 ± 0.12 g/100 g fresh weight...
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Mechanisms of Damage to DNA Labeled with Electrophilic Nucleobases Induced by Ionizing or UV Radiation
PublikacjaHypoxia—a hallmark of solid tumors—makes hypoxic cells radioresistant. On the other hand, DNA, the main target of anticancer therapy, is not sensitive to the near UV photons and hydrated electrons, one of the major products of water radiolysis under hypoxic conditions. A possible way to overcome these obstacles to the efficient radio- and photodynamic therapy of cancer is to sensitize the cellular DNA to electrons and/or ultraviolet...
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Small Hydropower Plants in Pomerania: The Example of Evolution of Modern Industrial Brick Architecture
PublikacjaModernism is usually recognized and associated with the aesthetics of the International Style, represented by white-plastered, horizontally articulated architecture with skimpy decoration, where function was the main imperative of the architects’ ambitions. The brick face of Modernism in Northern Europe reflected, in fact, the complexity of the modern change, breaking ties with the historic styles of the 19th century and being...
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Electron attachment to representative cations composing ionic liquids
PublikacjaUsing ab initio electronic structure methods with flexible atomic orbital basis sets, we investigated the electronic structure and stability of reduction products of selected representative cations (C+) constituting ionic liquids. We found that an electron attachment to such cations leads to the neutral radicals, whereas a subsequent attachment of another (i.e., excess) electron leads to adiabatically stable anions only in two...
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Social Entrepreneurship Research – Challenges, Explanations and Suggestions for the Field Development
PublikacjaEmploying critical review and reflection on the key literature in the area of entrepreneurship and management studies in social entrepreneurship field, this paper aims to outline the current challenges this field is facing, while introducing related explanations and suggesting required changes. The current field of social entrepreneurship research is at its nascent stage, which is determined by ongoing definitional debates and...
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Photocatalytic degradation and pollutant-oriented structure-activity analysis of carbamazepine, ibuprofen and acetaminophen over faceted TiO2
PublikacjaPhotocatalytic degradation of carbamazepine, ibuprofen, acetaminophen and phenol was studied in the presence of anatase photocatalyst, exposing three different crystal facets in the majority of {0 0 1}, {1 0 0} or {1 0 1}. It was found that octahedral anatase particles exposing {1 0 1} facets allow to achieve the best degradation and mineralization of all persistent organic pollutants. This confirms that the previous findings,...
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Bimetallic Bi/Cu0-catalyzed persulfate-based advanced oxidation processes towards clofibric acid degradation in wastewater
PublikacjaClofibric acid (CFA), an important blood-lipid regulatory drug is an emerging organic pollutant and widely reported in water resources. A novel bimetallic, bismuth/zero valent cupper (Bi/Cu0) catalyst was prepared which showed better physiological, structural, and catalytic properties than Cu0. The Bi/Cu0 effectively catalyzed persulfate (S2O82−) and caused 85% degradation of CFA. The Bi coupling improved reusability and stability...
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The effect of boron concentration on the electrical, morphological and optical properties of boron-doped nanocrystalline diamond sheets: Tuning the diamond-on-graphene vertical junction
PublikacjaIn this paper, the effect of boron doping on the electrical, morphological and structural properties of free-standing nanocrystalline diamond sheets (thickness ~ 1 μm) was investigated. For this purpose, we used diamond films delaminated from a mirror-polished tantalum substrate following a microwave plasma-assisted chemical vapor deposition process, each grown with a different [B]/[C] ratio (up to 20,000 ppm) in the gas phase....
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Reaktory elektrochemiczne w przemyśle - konstrukcja i zastosowania
PublikacjaZ biegiem lat reakcje elektrochemiczne przestały być postrzegane jedynie jako eksperymenty laboratoryjne lub proste baterie. Chociaż mechanizm reakcji i budowa prostych reaktorów znana jest ludzkości już od ponad 100 lat w ostatnich latach można zauważyć największy wzrost zainteresowania tą dziedziną. Nowy stale opracowywane są lepsze projekty budowy reaktorów. Modyfikacje to nie tylko rodzaje i formy materiałów, z których wykonane...
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Evaluation of RTKLIB's Positioning Accuracy Using low-cost GNSS Receiver and ASG-EUPOS
PublikacjaThe paper focuses on a comparison of different positioning methods provided by free and open source software (FOSS) package called RTKLIB. The RTKLIB supports real‐time and post‐processed positioning. The most important modes of operation tested by the authors are Kinematic, Static, Fixed and Precise Point Positioning (PPP). The data for evaluation were obtained from low‐cost Global Navigation Satellite System (GNSS) receiver....
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Recycling of raw materials, silicon wafers and complete solar cells from photovoltaic modules
PublikacjaPhotovoltaic modules (PVs) are an attractive way of generating electricity in reliable and maintenance-free systems with the use of solar energy. The average lifetime of photovoltaic modules is 25 to 30 years. To offset the negative impact of photovoltaic modules on the environment, it is necessary to introduce a long-term strategy that includes a complete lifecycle of all system components from the production phase through installation...
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The Boltzmann sequence-structure channel
PublikacjaWe rigorously study a channel that maps binary sequences to self-avoiding walks in the two-dimensional grid, inspired by a model of protein statistics. This channel, which we also call the Boltzmann sequence-structure channel, is characterized by a Boltzmann/Gibbs distribution with a free parameter corresponding to temperature. In our previous work, we verified experimentally that the channel capacity has a phase transition for...
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Determination of volatile organic compounds using solventless sample preparation techniques and gas chromatography
PublikacjaIn this paper the latest advances in the determination of volatile organic compounds using solvent-free extraction techniques in the sample preparation step are presented. A paper is focus mainly on one of the most popular sample preparation technique: solid-phase microextraction technique (SPME) combined with different detection systems and its applications to sampling of VOCs from the samples with different matrices. This paper...
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Thermodynamic Studies of Interactions between Sertraline Hydrochloride and Randomly Methylated β-Cyclodextrin Molecules Supported by Circular Dichroism Spectroscopy and Molecular Docking Results
PublikacjaThe interaction between sertraline hydrochloride (SRT) and randomly methylated β-cyclodextrin (RM β CD) molecules have been investigated at 298.15 K under atmospheric pressure. The method used—Isothermal Titration Calorimetry (ITC) enabled to determine values of the thermodynamic functions like the enthalpy (DH), the entropy (DS) and the Gibbs free energy (DG) of binding for the examined system. Moreover, the stoichiometry coefficient...
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The Examination of the Upper Layers of the Seabed by the Means of the Acoustic Methods
PublikacjaPropagation of acoustic waves in the sea, in particular in shallow sea, depends on several factors. The basic of them are source power and frequency of acoustic waves, spatial distribution inhomogeneous medium in which acoustic wave propagates, and distributions of speed of sound and density of seawater. The coastal conditions, which limit water medium from above (free surface of the sea) and from bottom (the seabed), are no less...
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Influence of Diosmin Treatment on the Level of Oxidative Stress Markers in Patients with Chronic Venous Insufficiency
PublikacjaOxidative stress plays an important role in the pathophysiology of many human disorders, while antioxidants prevent the development of various adverse symptoms. Diosmin is a natural flavonoid applied in vascular system disorders, especially in chronic venous insufficiency (CVI), and it plays a significant part in the alleviation of CVI symptoms. Due to antioxidant activity, it also has the ability to scavenge the oxygen free radicals...
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Impact of Low Switching-to-Fundamental Frequency Ratio on Predictive Current Control of PMSM: A simulation study
PublikacjaPredictive current control algorithms for permanent magnet synchronous (PMSM) drives rely on an assumption that within short intervals motor currents can be approximated with linear functions. This approximation may result either from discretizing the motor model or from simplifications applied to the continuous-time model. As the linear current approximation has been recognized as inaccurate in case when the drive operates with...
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Determination of selected parameters/ analytes in surface water samples collected in the surroundings of the capital of Spitsbergen (Longyearbyen)
PublikacjaPolar regions are extremely sensitive to pollution such as harmful gases, particles or toxic substances which affect the Arctic climate and ecosystems. Spitsbergen, as well as all Arctic region, because of its geographically distant location and lack of industry sector, should be free of chemical pollution. Despite this, many pollutants could be found in the Polar environment, for example in freshwaters. Their occurrence is related...
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Chemical composition of lipids isolated from selected organs and tissues of the raccoon dog (Nyctereutes procyonoides)
PublikacjaOur paper presents a qualitative analysis of particular lipid classes (phospholipids, triacylglycerols, cholesterol, free fatty acids) isolated from the tissues of raccoon dogs harvested in northeastern Poland. In all examined tissues (except for the liver) the dominant group of lipids were triacylglycerols. The amounts of lipids representing the other classes depended on the kind of tissue from which the fat was isolated. The...
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Theoretical Model of Acoustic Wave Propagation in Shallow Water
PublikacjaThe work is devoted to the propagation of low frequency waves in a shallow sea. As a source of acoustic waves, underwater disturbances generated by ships were adopted. A specific feature of the propagation of acoustic waves in shallow water is the proximity of boundaries of the limiting media characterised by different impedance properties, which affects the acoustic field coming from a source situated in the water layer “ deformed”...
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Quest for the Molecular Basis of Improved Selective Toxicity of All-Trans Isomers of Aromatic Heptaene Macrolide Antifungal Antibiotics
PublikacjaThree aromatic heptaene macrolide antifungal antibiotics, Candicidin D, Partricin A (Gedamycin) and Partricin B (Vacidin) were subjected to controlled cis-trans to all trans photochemical isomerization. The obtained all-trans isomers demonstrated substantially improved in vitro selective toxicity in the Candida albicans cells: human erythrocytes model. This effect was mainly due to the diminished hemotoxicity. The molecular modeling...
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Dynamics of Chains as a Tool to Study Thermomechanical Properties of Proteins.
PublikacjaPolymer dynamics can be formulated on different levels of detail. One approach eliminates microscopic degrees of freedom and a polymer molecule is represented by a simplified structure—a chain. In the simplest case monomers of ideal chain have fixed length, and their orientation is independent of the orientations and positions of neighbouring monomers. This is reason that two monomers can co-exist at the same place. Ideal chain...
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Optimization of Wireless Networks for Resilience to Adverse Weather Conditions
PublikacjaIn this chapter, we consider how adverse weather conditions such as rain or fog affect the performance of wireless networks, and how to optimize these networks so as to make them robust to these conditions. We first show how to analyze the weather conditions in order to make them useful for network optimization modelling. Using an example realistic network, we show how to optimize two types of wireless networks: free-space optical...
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Decoupled Kalman filter based identification of time-varying FIR systems
PublikacjaWhen system parameters vary at a fast rate, identification schemes based on model-free local estimation approaches do not yield satisfactory results. In cases like this, more sophisticated parameter tracking procedures must be used, based on explicit models of parameter variation (often referred to as hypermodels), either deterministic or stochastic. Kalman filter trackers, which belong to the second category, are seldom used in...
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The mechanical properties and bactericidal degradation effectiveness of tannic acid-based thin films for wound care
PublikacjaThe surface area is the most important aspect when considering the interactions between a material and the surrounding environment. Chitosan (CTS) and tannic acid (TA) were previously successfully tested by us to obtain thin films to serve as wound dressings or food packaging materials. However, surface properties as well as the antimicrobial activity of the material were not considered. They are important if the material is likely...
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Comparative study of a combined heat and power plant retrofitted by CO2 capture during the combustion of syngas from sewage sludge gasification versus zero-emission combustion of hydrogen produced using renewables
PublikacjaWith ecological requirements aimed at limiting the production of CO2, it is necessary to produce all, or most of the energy from RES. During the transformation process, ecological and highly efficient combustion power plants will be needed. The classic cycle of combined heat and power (CCGT) with green improvements will continue to be one of the most suitable technologies for this task. This article presents the modernization of...
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Grafting and reactive extrusion technologies for compatibilization of ground tyre rubber composites: Compounding, properties, and applications
PublikacjaChemical modification of ground tyre rubber (GTR) to compatibilize it with the matrix is a well-known approach. Based on our recent review of the surface etching methods used in GTR modification, the purpose of the current work is to take a deeper look into more advanced methods such as grafting and reactive extrusion. While grafting is more efficient in achieving compatibility, however, it usually involves multi-step synthesis...
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Raman investigation of the patina layers on Hungarian copper ingots from a fifteenth century shipwreck
PublikacjaWe report results of the patina study of underwater archeological finding ofmedieval copper objects performed by means of the Raman and complementary spectroscopic techniques. The objects were found submerged in the sea as cargo part of the ship which sunk in the Gulf of Gdańsk in 1408. The excavated collection consists of 230 oval ingots of the size and mass up to about 60 cm and 18 kg (total of 2 tons), respectively. In the Raman...