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Applying Fuzzy Logic of Expert Knowledge for Accurate Predictive Algorithms of Customer Traffic Flows in Theme Parks
PublikacjaThis study analyzes two forecasting models based on the application of fuzzy logic and evaluates their effectiveness in predicting visitor expenditure and length of stay at a popular theme park. The forecasting models are based on a set of more than 600 decision rules constructed in the form of a complex series of IF-THEN statements. These algorithms store expert knowledge. A descriptive instrument that records the individual visitor's...
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Analysis of Interspike-Intervals for the General Class of Integrate-and-Fire Models with Periodic Drive
PublikacjaWe study one-dimensional integrate-and-fire models of the general type x˙=F (t, x) and analyze properties of the firing map which iterations recover consecutive spike timings. We impose very week constraints for the regularity of the function F (t, x), e.g. often it suffices to assume that F is continuous. If additionally F is periodic in t, using mathematical study of the displacement sequence of an orientation preserving circle...
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50’ Sail Catamaran with Hybrid Propulsion, Design, Theoretical and Experimental Studies
PublikacjaThe development of modern lithium batteries and propulsion systems now allows the use of complex propulsion systems for vessels of various sizes. As part of the research and implementation project, a parallel hybrid drive system was designed, built and then tested in the laboratory. The experimental studies conducted allowed for the measurements of power, fuel consumption and electric power distribution in various operating modes...
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Emulator and simulator of Terma SCANTER and ARPA radar data server
PublikacjaThe software solutions presented in this paper generate real-time data compatible with ARPA radar standard as well as Terma SCANTER 2001 radar cooperating with Video Distribution and Tracking (VDT) server. Two different approaches to this problem are considered: emulation based on the data captured from real devices and simulation of objects on the sea. For both of them architecture, implementation details and functional test results...
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Modelowanie przepływu pary przez okołodźwiękowe wieńce turbinowe z użyciem sztucznych sieci neuronoych
PublikacjaNiniejszy artykuł stanowi opis modelu przepływu pary przez okołodźwiękowe stopnie turbinowe, stworzonego w oparciu o sztuczne sieci neuronowe (SSN). Przedstawiony model neuronowy pozwala na wyznaczenie rozkładu wybranych parametrów w analizowanym przekroju kanału przepływowego turbiny dla rozpatrywanego zakresu wartości ciśnienia wlotowego.
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Uproszone modelowanie sieci dystrybucyjnej na potrzeby analiz przyłączeniowych
PublikacjaW artykule przedstawiono rozważania na temat sposobu modelowania sieci średniego (SN) i niskiego (nn) napięcia na potrzeby wykonywania analiz przyłączeniowych przez operatorów sieci dystrybucyjnej. Przeprowadzono dyskusję na temat możliwych do wykonania uproszczeń w modelowaniu sieci, które są do zaakceptowania z punktu widzenia uzyskiwanego wyniku końcowego. Głównym elementem wymuszającym uproszenia w modelowaniu jest środowisko...
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Easy recipes for cooperative smoothing
PublikacjaIn this paper we suggest how several competing signal smoothers, differing in design parameters, or even in design principles, can be combined together to yield a better and more reliable smoothing algorithm. The proposed heuristic, but statistically well motivated, fusion mechanism allows one to combine practically all kinds of smoothers, from simple local averaging or order statistic filters, to parametric smoothers designed...
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Geometrically Nonlinear Analysis of Functionally Graded Shells Based on 2-D Cosserat Constitutive Model
PublikacjaIn this paper geometrically nonlinear analysis of functionally graded shells in 6-parameter shell theory is presented. It is assumed that the shell consists of two constituents: ceramic and metal. The mechanical properties are graded through the thickness and are described by power law distribution. Formulation based on 2-D Cosserat constitutive model is used to derive constitutive relation for functionally graded shells. Numerical...
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Improving all-reduce collective operations for imbalanced process arrival patterns
PublikacjaTwo new algorithms for the all-reduce operation optimized for imbalanced process arrival patterns (PAPs) are presented: (1) sorted linear tree, (2) pre-reduced ring as well as a new way of online PAP detection, including process arrival time estimations, and their distribution between cooperating processes was introduced. The idea, pseudo-code, implementation details, benchmark for performance evaluation and a real case example...
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Elastoplastic nonlinear FEM analysis of FGM shells of Cosserat type
PublikacjaThe paper is a continuation of [1] where the formulation of the elastic constitutive law for functionally graded materials (FGM) on the grounds of nonlinear 6-parameter shell theory with the 6th parameter (the drilling degree of freedom) was presented. Here the formulation is extended to the elasto-plastic range. The material law is based on Cosserat plasticity and employs the well-known Tamura-Tomota-Ozawa (TTO) [2] mixture...
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A robust 18-pulse diode rectifier with coupled reactors
PublikacjaThe article presents the principle of operation and selected results of simulation and laboratory tests of the 18-pulse rectifier system with coupled reactors and small series active power filter. The presented system makes it possible to reduce, especially in distribution supply networks, undesired higher current harmonics. The 18-pulse nature of operation of the rectifier is reached using a set of coupled three-phase network...
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The Imaging of Gdansk Bay Seabed by Using Side Sonar
PublikacjaThis paper is mainly aimed at presentation of an impact of environmental conditions on imaging accuracy by using hydro-acoustic systems in waters of a high non-uniformity of spatial distribution of hydrological parameters. Impact of refraction on erroneous estimation of range, in case of wave radiation into water under a large angle, like in side sonars or multi-beam echo-sounders, is especially important. In this paper seasonal...
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Hierarchical random models in road transport safety
PublikacjaIn this paper multilevel approach to the issue of road safety level on the road network of European regions, classified as NUTS 2 in statistical databases of the EU, has been presented. The risk calculated as the number of death casualties in road accidents per 100,000 inhabitants of a given region has Poisson distribution. Therefore, generalized Poisson model has been assumed in the modelling process. Multilevel stochastic analysis...
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The Influence of Shear Deformation in analysis of plane frames
PublikacjaThe focus of the paper is to investigate the influence of shear deformation effect on the distribution of internal forces and frame deformation. To estimate shear deformation effect, the Timoshenko beam theory and the concept of shear deformation coefficients are used. Analysis of example frames gives the possibility to evaluate what have the most impact on size of shear deformation and in which type of frames the shear deformation...
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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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Optimised allocation of actuators for DWDS
PublikacjaThis paper addresses the problem of actuators’ allocation within networked structured system, namely allocation of disinfectant booster stations within Drinking Water Distribution System (DWDS), under receding horizon optimised control – Model Predictive Control (MPC) to be exact. The allocation task is kept within dynamic multiobjective optimisation framework. The MPC is defined as a single objective predictive operator. Two numerical...
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Application of gpr method in diagnostics of reinforced concrete structures
PublikacjaThis paper presents an application of the ground penetration method (GPR) for diagnostics of reinforced concrete structures. In situ measurements were conducted for three civil engineering structures: the ground floor structure, the abutment of the railway viaduct and the concrete well. The dual polarized ground penetrating radar with the antenna operating at a center frequency of 2 GHz was used for GPR surveys. Three different...
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Analysis of the Usefulness of Cheap Audio Recorders for Spectral Measurement of Environmental Noise
PublikacjaEnvironmental noise pollution is nowadays one of the most serious health threats. The impact of noise on the human body depends not only on the sound level but also on its spectral distribution. Reliable measurements of the environmental noise spectrum are often hampered by the very high price of top quality measuring devices. This paper explores the possibility of using much cheaper audio recorders for the frequency analysis....
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The influence of stainless steels microstructure evolution on the mechanical properties of pressure installation elements
PublikacjaIn this paper results of FEM analysis performed for pipe and 90o elbow, made of super duplex stainless steel, after precipitation of sigma phase (),were presented. Heat treatment conditions simulate accidental overheating that can occur in nuclear installations after cooling circulation fails. For initial and modified microstructure tensile test was performed and numerical description of work hardening curves was done. Verification...
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The influence of stainless steels microstructure evolution on the mechanical properties of pressure installation elements
PublikacjaIn this paper results of FEM analysis performed for pipe and 90o elbow, made of super duplex stainless steel, after precipitation of sigma phase (s), were presented. Heat treatment conditions simulate accidental overheating that can occur in nuclear installations after cooling circulation fails. For initial and modified microstructure tensile test was performed and numerical description of work hardening curves was done. Verification...
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Ordinal pattern statistics for the assessment of heart rate variability
PublikacjaThe recognition of all main features of a healthy heart rhythm (the so-called sinus rhythm) is still one of the biggest challenges in contemporary cardiology. Recently the interesting physiological phenomenon of heart rate asymmetry has been observed. This phenomenon is related to unbalanced contributions of heart rate decelerations and accelerations to heart rate variability. In this paper we apply methods based on the concept...
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TS-based RSM-aided design of cold-formed steel stiffened C-sectional columns susceptible to buckling
PublikacjaThe paper focuses on joint-performance analysis of a built-up cold-formed thin-walled C-sectional column with a fillister (stiffener) of the same type, interconnected with a series of bolts located along the length of the compressed members in specific spacing. The quantity of bolts and the non-connected starting distance of the fillister are considered random variables of the problem. Optimal distribution of joints on the stiffener...
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The project IDENT: Multimodal biometric system for bank client identity verification
PublikacjaBiometric identity verification methods are implemented inside a real banking environment comprising: dynamic handwritten signature verification, face recognition, bank cli-ent voice recognition and hand vein distribution verification. A secure communication system based on an intra-bank client-server architecture was designed for this purpose. Hitherto achieved progress within the project is reported in this paper with a focus...
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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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Optimization of Single-Sided Lapping Kinematics Based on Statistical Analysis of Abrasive Particles Trajectories
PublikacjaThe chapter presents the influence of selected kinematic parameters on the geometrical results of the single-sided lapping process. The optimization of these parameters is aimed at improving the quality and flatness of the machined surfaces. The uniformity of tool wear was assumed as main optimization criterion. Lapping plate wear model was created and in detail was analyzed. A Matlab program was designed to simulate the abrasive...
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Minimising the Churn Out of the Service by Using a Fairness Mechanism
PublikacjaThe paper proposes an algorithm of bandwidth distribution, ensuring fairness to end-users in computer networks. The proposed algorithm divides users into satisfied and unsatisfied users. It provides fairness in terms of quality of experience (QoE) for satisfied users and quality of service (QoS) for unsatisfied users. In this paper, we present detailed comparisons relevant to service providers to show the advantages of the proposed...
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Medium-sized cyclic bis(anisylphosphonothioyl)- disulfanes and their corresponding cyclic sulfane-structures and most characteristic reactions
PublikacjaCyclic 8-, 9-, 10-, and 12-membered bis(anisylphosphonothioyl)disulfanes were synthesized. Next, structurally related 7 to 9-membered cis and trans sulfanes were isolated as a result of sulfur atom extrusion from the parent cyclic disulfanes. The results of the desulfurization of the disulfanes were compared to the results obtained for desulfurization of the respective bis(anisylphosphodithioates). Cyclic disulfanes predominantly...
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Hydrauliczna wiarygodność wyników pomiarów terenowych stosowanych do identyfikacji oporności hydraulicznej przewymiarowanych sieci wodociągowych
PublikacjaPublikacja zawiera zalecenia metodyczne dotyczące identyfikacji oporności hydraulicznej w przewymiarowanych sieciach wodociągowych na tle spotykanych nieprawidłowości. Krytycznie oceniono wyniki pomiarów terenowych, które zastosowano do tarowania komputerowych modeli przepływów (KMP) pomimo, że nie spełniały kryterium hydraulicznej wiarygodności. Ponadto zaproponowano spadek hydrauliczny jako obiektywny wskaźnik wiarygodności pomiarów,...
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Processing and structure–property relationships of natural rubber/wheat bran biocomposites
PublikacjaIn this work, wheat bran was used as cellulosic filler in biocomposites based on natural rubber. The impact of wheat bran content [ranging from 10 to 50 parts per hundred rubber (phr)] on processing, structure, dynamic mechanical properties, thermal properties, physico-mechanical properties and morphology of resulting biocomposites was investigated. For better characterization of interfacial interactions between natural rubber...
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The impact of hydrological research, municipal authorities, and residents on rainwater management in Gdańsk (Poland) in the process of adapting the city to climate change
PublikacjaAim of the study The city of Gdańsk faces changing climatic conditions that result in a higher frequency of extreme weather events. In response to the increasingly frequent appearance of flash floods, scientific research was carried out on changes in the probability of the occurrence of maximum daily precipitation in Gdańsk. The purpose of this paper is to show the role of hydrological research (science), decisions of local authorities...
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Steady magnetohydrodynamic flow in a diverging channel with suction or blowing
PublikacjaAn analysis is made of steady two-dimensional divergent flow of an electrically conducting incompressible viscous fluid in a channel formed by two non-parallel walls, the flow being caused by a source of fluid volume at the intersection of the walls. The fluid is permeated by a magnetic field produced by an electric current along the line of intersection of the channel walls. The walls are porous and subjected to either suction...
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Quantitative study of free convective heat losses from thermodynamic partitions using Thermal Imaging
PublikacjaThe following paper presents a simple method of determining the presence, distribution and values of heat losses from external building walls as thermodynamic partitions using a Thermal Imaging Camera (TIC). According to Fourier's equation, the value of heat loss is proportional to the temperature gradient ∂t/∂y|y=0 in air in the y direction perpendicular to the heated surface. Unfortunately, air temperature cannot be measured...
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Effect of small quantities of potassium promoter and steam on the catalytic properties of nickel catalysts in dry/combined methane reforming
PublikacjaCarbon dioxide and methane are two of the principal greenhouse gases. Reduction of their content in the atmosphere is currently the subject of much worldwide research. Dry and combined reforming of methane are effective methods of CO2 and CH4 utilization and production of synthesis gas (syngas) in chemical technology. Testing of catalysts that provide the desired H2/CO ratio and long operation time is one of the critical aspects...
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Contribution of dynamic vehicle loads to pavement failure
PublikacjaPavement surfaces are not ideally even, which causes dynamic loads of vehicle axles. Distribution of dynamic loads of a given axle is similar to normal distribution and can be described by static load and dynamic load coefficient. The dynamic load coefficient depends on road profile, vehicle speed, properties of suspensions and static load of axle. While for a given road section road profile remains constant, vehicle speed and...
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Effect of pavement roughness and vehicle dynamic loads on decrease of fatigue life of flexible pavements
PublikacjaDue to the fact that pavement surfaces are not ideally even, dynamic loads of vehicle axles deviate from static loads. Higher dynamic loads contribute to faster pavement distress. The distribution of dynamic loads is similar to normal distribution and can be described by static load and factors DI (dynamic impact) and DLC (dynamic load coefficient). With the deterioration of pavement condition its evenness decreases as well and...
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Flow maldistribution and its mitigation in mini heat exchangers
PublikacjaIn the present paper, a detailed numerical investigation has been carried out to analyze the flow maldistribution in 50 parallel 1 mm x 1 mm rectangular minichannels and 1 mm depth minigap section with rectangular, trapezoidal, triangular or concave mani-folds in Z-type flow configuration (16 different cases). The working medium was ethanol and the mass flow rate was 5×10-4 kg/s. Both sections was heated from the bottom side. Heat...
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Mitigation of the Flow Maldistribution in Minichannel and Minigap Heat Exchangers by Introducing Threshold in the Manifolds
PublikacjaIn the present paper, a detailed numerical investigation has been carried out to analyze the flow maldistribution in 50 parallel rectangular cross-section (1 mm depth and 1 mm width) minichannels and minigap section (1 mm depth and 99 mm width) with rectangular/trapezoidal manifolds in Z-type flow configuration. The author carried out numerical investigation with various mass flowrates, namely 0.05 kg/s, 0.1 kg/s and 0.2 kg/s which...
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Stabalization of solar-panel energy system for Pakistani household
PublikacjaRenewable energy resources such as Sun and wind are getting popular and easier to use day by day. It is a better method to fulfill our demands as sun is a continuous source of energy for Earth. Many countries are fulfilling their demands by Solar Panels. Solar panel is used as a converter between sunlight and electrical energy. This research paper is going to tell that how to obtain electrical energy from sunlight more efficiently...
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Thermal decomposition kinetics of dynamically vulcanized polyamide 6-acrylonitrile butadiene rubber-halloysite nanotube nanocomposites
PublikacjaThermally stable thermoplastic elastomer nanocomposites based on polyamide 6 (PA6), acrylonitrile butadiene rubber (NBR), and halloysite nanotubes (HNTs) were dynamically vulcanized, and their nonisothermal decomposition kinetics were examined. The Friedman, Kissinger–Akahira–Sunose (KAS), Ozawa–Wall–Flynn (FWO), and modified Coats–Redfern (m‐CR) isoconversional models were used to obtain information about the kinetics of the thermal...
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2-bondage in graphs
PublikacjaA 2-dominating set of a graph G=(V,E) is a set D of vertices of G such that every vertex of V(G)D has at least two neighbors in D. The 2-domination number of a graph G, denoted by gamma_2(G), is the minimum cardinality of a 2-dominating set of G. The 2-bondage number of G, denoted by b_2(G), is the minimum cardinality among all sets of edges E' subseteq E such that gamma_2(G-E') > gamma_2(G). If for every E' subseteq E we have...
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A novel luminescent chemical sensor for the determination of Pb 2+ and Cu 2+ ions
PublikacjaSilica xerogel surface grafted with aminopropyl (PrNH2) groups was additionally treated by cetyltrimethylammonium bromide (CTAB) surfactant and ascorbic acid (asc) in alkaline solution. This material symbolized as SiO2-PrNH2-CTAB/asc, proved to be a stable luminescent material, exhibited an emission band peaked at 393 nm under excitation wavelength 335 nm. Time evolution of the band intensity suggests changes of defect concentration...
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Frequency-Reconfigurable Hybrid SIW-Based Self-Diplexing Antenna Using Solid and Liquid Dielectric Loading
PublikacjaThis paper presents a novel frequencyreconfigurable self-diplexing antenna (SDA) utilizing a hybrid substrate-integrated waveguide (SIW). The antenna comprises a radiating slot, a feeding network, and a hybrid SIW cavity featuring half-mode circular and half-mode rectangular SIW structures. The unique feature of this antenna lies in its fine-tuning capability of each resonant frequency by inserting or injecting solid and liquid...
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Investigating COVID-19 active pharmaceutical ingredients (APIs) degradation using Peroxydisulfate/FeMnOx binary metal oxide/Ultrasound System
PublikacjaDegradation of Favipiravir using a hybrid system of peroxydisulfate, FeMnOx binary metal oxide, and ultrasound irradiation was studied. A novel catalyst was synthesized with deep eutectic solvent (DES). The effects of DES type on catalytic performance was evaluated and the catalysts were characterized using XRD, SEM, BET, XPS, and EDS. DES-based catalysts exhibited higher efficiency due to structure change, surface area enhancement...
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Ultrafast high-temperature sintering (UHS) of cerium oxide-based compound
PublikacjaUltrafast high-temperature sintering (UHS) is an innovative sintering technique that can densify ceramics in a few seconds, dramatically reducing the carbon footprint and firing costs. In this work, the feasibility of applying UHS in Gd-doped ceria (GDC) and GDC-Er-stabilized bismuth oxide (ESB) composite powders was investigated. At high UHS currents (22-24 A), a fully dense GDC sample with a large grain size was obtained. Nonetheless,...
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Multichannel self-optimizing narrowband interference canceller
PublikacjaThe problem of cancellation of a nonstationary sinusoidal interference, acting at the output of an unknown multivariable linear stable plant, is considered. No reference signal is assumed to be available. The proposed feedback controller is a nontrivial extension of the SONIC (self-optimizing narrowband interference canceller) algorithm, developed earlier for single-input, single-output plants. The algorithm consists of two loops:...
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Preparation and characterization of genipin cross-linked porous chitosan–collagen–gelatin scaffolds using chitosan–CO2 solution
PublikacjaNovel porous scaffolds composed of chitosan, collagen and gelatin were prepared by the multistep procedure involving final freeze-drying and characterized. To eliminate the need for residual acid removal from the material after drying, carbon dioxide saturation process was used for chitosan blend formulation. The use of CO2 for chitosan dissolution made the scaffold preparation process more reproducible and economically sustainable....
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Luminescence recognition material as an INHIBIT logic gate in presence of Pb2+ and Cu2+ ions in aqueous solutions
PublikacjaA recognition material consisting of silica xerogel with amino-modified surface selectively recognizes Pb2+ and Cu2+ (but only in presence of Pb2+ ions) in aqueous solutions of other metal ions. The analytical action of the material is based on a significant change in luminescence emission spectra of the material after chemisorption of Pb2+ ions. In the presence of Pb2+ in octahedral coordination environment, a new broad and strong...
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Local Conformation and Cocrystallization Phenomena in Renewable Diaminoisoidide-Based Polyamides Studied by FT-IR, Solid State NMR, and WAXD
PublikacjaBiobased polyamides synthesized from diaminoisoidide (DAII), 1,4-diaminobutane, and sebacic acid are investigated by FT-IR, 13C{1H} magic-angle spinning/cross-polarization (CP/MAS) NMR spectroscopy, and WAXD. Their molecular conformation and mobility undergo distinct changes as a function of temperature and diaminoisoidide content in the compositions. The presence of randomly distributed diaminoisoidide (DAII) in the polyamides...
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The Ellenbogen’s “Matter as Software” Concept for Quantum Computer Implementation: IV. The X@C60 Molecular Building Blocks (MBBs) and Computing System Lifetime Estimation
PublikacjaThe problem of approximate lifetimes of individual X@C60 MBBs and tip-based nanofabricated quantum computing device systems is discussed under the conservative assumption of single-point failure. A single chemical transformation of the C60 cage into high-energy opened o-C60 isomer which forms the communication canal for the low energy transfer of an X atom from X@C60 MBB to the outside environment was studied. According to the...
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Nano-engineered diamond-based materials for supercapacitor electrodes: A review
PublikacjaOwing to the popularity of carbon-based supercapacitors, diamond has also been examined as a potential candidate with unique advantages such as a wide electrochemical potential window and stable capacitive behavior in both aqueous and non-aqueous electrolytes. Moreover, its chemical stability in harsh environments at extreme applied potential and current provides rare opportunities for designing new supercapacitors. Owing to the...