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Proton transfer and hydrogen bonds in supramolecular, self-assembled structures of imidazolium silanethiolates. X-ray, spectroscopic and theoretical studies
PublikacjaThe reaction of 1-methylimidazole, 2-ethyl-4-methylimidazole and 2-ethylimidazole with tris(2,6- diisopropylphenoxy)silanethiol (TDST) leads to the formation of three new salts, which have been characterized by elemental analyses, thermogravimetric analyses, FTIR spectroscopy, and their structures were determined by single-crystal X-ray diffraction. Structural analyses indicate that in all three compounds a proton transfer has...
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Current harmonic controller in multiple reference frames for series active power filter integrated with 18-pulse diode rectifier
PublikacjaThe paper presents the control system and selected results of experimental tests of the AC/DC power converter consisting of an 18-pulse diode rectifier based on coupled reactors and a serial active power filter. Proportional integral controllers with decoupling components are implemented in multiple reference frames for selective line current harmonic suppression. The regulator is provided with a backtracking anti-windup mechanism...
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A facile method for Tauc exponent and corresponding electronic transitions determination in semiconductors directly from UV–Vis spectroscopy data
PublikacjaIn this work, a facile method allowing for estimation of the exponent in the Tauc equation directly from the UV–vis spectra is presented. It is based on the Taylor expansion of the logarithmic version of the Tauc equation. The Tauc exponent is calculated from the tangent slope of the absorption data. Knowledge of this coefficient provides information about the optical transition types and is used as an input for the calculations...
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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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Dynamic Research of Masonry Vault in a Technical Scale
PublikacjaThe paper presents preliminary results of dynamic tests of the masonry barrel vault in a technical scale. Experimental studies are intended to identify material properties of homogenized masonry vaults under dynamic loads. The aim of the work is to create numerical models to analyse vault’s dynamic response to dynamic loads in a simplest and accurate way. The process of building the vault in a technical scale is presented in the...
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Influence of orientational disorder on the optical absorption properties in hybrid metal‐halide perovskite CH3NH3PbI3. A combined DFT/TD‐DFT and experimental study.
PublikacjaAn experimental and theoretical investigation is reported to analyze the relation between the structural and absorption properties of CH3NH3PbI3 in the tetragonal phase. More than 3000 geometry optimizations were performed in order to reveal the structural disorder and to identify structures with the lowest energies. The electronic structure calculations provide an averaged band gap of 1.674 eV, which is in excellent agreement...
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Smart Weighing Scale with Feet-Sampled ECG
PublikacjaIn a smart home, health and well-being monitoring systems could be embedded in everyday devices providing a pervasive care. A home bathroom scale is an example of such a device, typically used to measure body weight and very often its composition (e.g. body water/fat percentage). In this paper, we analyzed a potential use of the bathroom scale to measure electrocardiogram (ECG) from electrodes located on the scale's tile. In particular...
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Stability by linear approximation for time scale dynamical systems
PublikacjaWe study systems on time scales that are generalizations of classical differential or difference equations and appear in numerical methods. In this paper we consider linear systems and their small nonlinear perturbations. In terms of time scales and of eigenvalues of matrices we formulate conditions, sufficient for stability by linear approximation. For non-periodic time scales we use techniques of central upper Lyapunov exponents...
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The Large Customer Reactive Power Control Possibilities
Publikacjan this paper the authors wish to draw attention to the rationale for, and the possibility of, the use of local reactive power sources by the Transmission Node Master Controller (TNMC). Large Customers (LC) are one of the possible reactive power sources. The paper presents the issues related to the need for coordination between the control systems installed in the LC network, and coordination between control systems of the LC as...
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Numerical solutions for large deformation problems in geotechnical engineering
PublikacjaThe problem of large deformations often occurs in geotechnical engineering. Numerical modeling of such issues is usually complex and tricky. The chosen solution has to implicate soil-soil and soil-structure interactions. In this paper, a review of the most popular numerical methods for large deformation problems is presented. The Coupled Eulerian-Lagrangian (CEL) method, the Arbitrary Lagrangian-Eulerian (ALE) method, the Smoothed...
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Adaptive Hounsfield Scale Windowing in Computed Tomography Liver Segmentation
PublikacjaIn computed tomography (CT) imaging, the Hounsfield Unit (HU) scale quantifies radiodensity, but its nonlinear nature across organs and lesions complicates machine learning analysis. This paper introduces an automated method for adaptive HU scale windowing in deep learning-based CT liver segmentation. We propose a new neural network layer that optimizes HU scale window parameters during training. Experiments on the Liver Tumor...
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Comparison of various speech time-scale modificartion methods
PublikacjaThe objective of this work is to investigate the influence of the different time-scale modification (TSM) methods on the quality of the speech stretched up using the designed non-uniform real-time speech time-scale modification algorithm (NU-RTSM). The algorithm provides a combination of the typical TSM algorithm with the vowels, consonants, stutter, transients and silence detectors. Based on the information about the content and...
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Symmetrical and unsymmetrical diphosphanes with diversified alkyl, aryl and amino substituents
PublikacjaWe present the comprehensive study of diphosphanes with diversified substituents regarding their syntheses, structures, and properties. To this end, we have synthesized a series of novel unsymmetrical alkyl, aryl and amino-substituted diphosphanes of the general formula R1R2P-PR3R4 (where R1, R2, R3, R4 = tBu, Ph, Et2N or iPr2N) via salt metathesis reactionof halophosphanes with metal phosphides in high yield. We vastly expanded...
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Theoretical studies of fragmentation processes of neutral and ionized furan molecule
PublikacjaThis PhD thesis focuses on the fragmentation mechanism of the furan molecule in the gas phase. The approach taken in this work comprised of three theoretical methodologies considering the dynamical, energetical and entropic aspects of the studied process. First, molecular dynamics simulations were performed. Next, the potential energy surfaces were explored at the DFT/B3LYP level of theory. Finally, a new statistical Microcanonical...
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Comparison of effectiveness of musical sound separation algorithms employing neural networks.
PublikacjaNiniejszy referat przedstawia kilka algorytmów służących do separacji dźwięków instrumentów muzycznych. Zaproponowane podejście do dekompozycji miksów dźwiękowych opiera się na założeniu, że wysokość dźwięków w miksie jest znana, tzn. wejściem dla algorytmów jest przebieg zmian wysokości dźwięków składowych miksu. Proces estymacji fazy i amplitudy składowych harmonicznych wykorzystuje dopasowywanie zespolonych przebiegów harmonicznych...
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Density functional LCAO calculations of vibrational modes and phonon density of states in the strained single-layer phosphorene
PublikacjaThe paper presents an investigation of phosphorene under axial strain on the phonon density of states and vibrational modes. The studies were performed by means of density functional theory (DFT) within the linear combination of atomic orbitals (LCAO). The strained models were constructed using optimised supercell techniques. The vibrational mode spectra were estimated for strains applied for both the zigzag and armchair directions...
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Hydration of simple amides. FTIR spectra of HDO and theoretical studies
PublikacjaZastosowano metodę ważonych widm różnicowych do opisu hydratacji amidów w roztworach wodnych: formamidu, N-metyloformamidu, N,N-dimetyloformaidu, acetamidu, N-metyloacetamidu, N,N-dimetyloacetamidu. Narzędziem wspomagającym interpretację wyników eksperymentalnych są struktury agregatów solwatacyjnych wokół cząsteczki substancji rozpuszczonej uzyskane na podstawie obliczeń teoretycznych metodą ab initio z korelacją elektronową...
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Electronic structure of TbBa2Cu3O7
PublikacjaW pracy wykonano obliczenia kwantowomechaniczne struktury elektronowej hipotetycznego materiału TbBa2Cu3O7 (Dy123) metodą FP-LAPW (full potential - linearized augmented plane wave) w ramach formalizmu DFT (density functional theory) stosując przybliżenie GGA (generalized gradient approximation). Ze względu na silne oddziaływania korelacyjne elektronów 4f w atomie Tb zastosowano dodatkowo poprawkę kulombowską U w ramach modelu...
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Absorptive Desulfurization of Model Biogas Stream Using Choline Chloride-Based Deep Eutectic Solvents
PublikacjaThe paper presents a synthesis of deep eutectic solvents (DESs) based on choline chloride (ChCl) as hydrogen bond acceptor and phenol (Ph), glycol ethylene (EG), and levulinic acid (Lev) as hydrogen bond donors in 1:2 molar ratio. DESs were successfully used as absorption solvents for removal of dimethyl disulfide (DMDS) from model biogas steam. Several parameters affecting the absorption capacity and absorption rate have been...
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Theoretical and Experimental Studies on the Visible Light Activity of TiO2 Modified with Halide-Based Ionic Liquids
PublikacjaFormation of a surface complex between organic molecules and TiO2 is one of the possible strategies for the development of visible light-induced TiO2 photoactivity. Herein, three ionic liquids (ILs) with the same cation and dierent anions (1-butylpirydynium chloride/bromide/iodide) have been applied for the surface modification of TiO2 and to understand the role of anions in visible light-induced activity of ILs-TiO2 systems. Photocatalytic...
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Mechanochemically synthesized Mn3O4@β-cyclodextrin mediates efficient electron transfer process for peroxymonosulfate activation
PublikacjaThe rational surface engineering of heterogeneous catalysts is of great significance in advanced oxidation processes (AOPs) for eliminating refractory contaminants but remains challenging. In this study, β-cyclodextrin modified Mn3O4 (Mn3O4@β-CD) was prepared through a mechanochemical approach for peroxymonosulfate (PMS) activation, which achieved efficient bisphenol A (BPA) removal via electron transfer process (ETP). The reactive...
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A DFT/TD DFT study of the structure and spectroscopic properties of 5-methyl-2-(8-quinolinyl)benzoxazole and its complexes with Zn(II) ion
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Development of cluster analysis methodology for identification of model rainfall hyetographs and its application at an urban precipitation field scale
PublikacjaDespite growing access to precipitation time series records at a high temporal scale, in hydrology, and particularly urban hydrology, engineers still design and model drainage systems using scenarios of rainfall temporal distributions predefined by means of model hyetographs. This creates the need for the availability of credible statistical methods for the development and verification of already locally applied model hyetographs....
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Properties of Oxygen Vacancy and Hydrogen Interstitial Defects in Strontium Titanate: DFT + Ud,p Calculations
PublikacjaThis work presents extensive theoretical studies focused on the mixed ion-electron transport in cubic strontium titanate (STO). A new approach to the description of this difficult system was developed within the framework of linear-scaling Kohn–Sham density functional theory, as realized in the ONETEP program. The description we present is free of any empirical parameters and relies on the Hubbard U and Hund’s J corrections applied...
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On the Peano Theorem for Some Functional Differential Equations on Time Scale
PublikacjaThe Peano Theorem for some functional differential equations on time scale is proved. Assumptions are of Caratheodory type. Two counter examples for false Peano theorems in the literature are presented.
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Topic 1: Transformations / Spatial form design, scale 1:1
Kursy OnlineBrief description: The subject matter of the spatial form design classes is transformation. First, a black square becomes a flat graphic composition, which is then converted to color. The final stage of the transformation process is a spatial object, which is by assumption devoid of any utilitarian functions. Course content / classes schedule: 1. Graphic. The task is to create an achromatic flat composition in the contrast...
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Synthetic, Structural, and Spectroscopic Characterization of a Novel Family of High-Spin Iron(II) [(β-Diketiminate)(phosphanylphosphido)] Complexes
PublikacjaThis work describes a series of iron(II) phosphanylphosphido complexes. These compounds were obtained by reacting lithiated diphosphanes R2PP(SiMe3)Li (R = t-Bu, i-Pr) with an iron(II) β-diketiminate complex, [LFe(μ2-Cl)2Li(DME)2] (1), where DME = 1,2-dimethoxyethane and L = Dippnacnac (β-diketiminate). While the reaction of 1 with t-Bu2PP(SiMe3)Li yields [LFe(η1-Me3SiPPt- Bu2)] (2), that of 1 with equimolar amounts of i-Pr2PP(SiMe3)Li,...
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A scale with ECG measurements capability for home cardiac monitoring
PublikacjaPresented device -a scale developed for enabling extra measurements, in addition to body weight and composition, the electrical activity of the heart (electrocardiogram - ECG) and the level of oxygen saturation in the blood SaO2. Electrical activity is recorded in the form of six leads, socalled - limb leads. The device allows measurement of all standard limb leads and without the need for additional procedures. ECG, although the...
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Unexpected Z/E isomerism of N-methyl-O-phosphothioyl benzohydroxamic acids, their oxyphilic reactivity and inertness to amines
PublikacjaThiophosphinoylation of N-methyl p-substituted benzohydroxamic acids using disulfanes (method A) or diphenylphosphinothioyl chloride (method B) provides only one conformer of the respective O-phosphothioyl derivative (Xray and NMR analysis). Undergoing the P-transamidoxylation reaction is an evidence of the reversibility of thiophosphinoylation. Only those products containing strong EWG substituents in the aroyl residue or bulky...
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Towards sugar-derived polyamides as environmentally friendly materials
PublikacjaAs part of our ongoing study investigating isohexide-based polyamides, we have synthesized isosorbide(bis(propan-1-amine)) (DAPIS) and studied its reactivity in the polymerization towards fully biobased polyamides. Polycondensation of nylon salts with various contributions of DAPIS afforded a family of homo- and copolyamides, which were characterized using complementary spectroscopic techniques. The chemical structure of the materials...
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Effect of urea and glycine betaine on the hydration sphere of model molecules for the surface features of proteins
PublikacjaWater properties may significantly affect protein stability. Osmolytes are compounds that intrinsically affect water in many different ways and thus can influence proteins with this type of indirect mechanism. In this study, we characterize water properties in ternary solutions: model–water–osmolyte, with two model molecules: N-methylacetamide (NMA) and dimethyl sulfoxide (DMSO) and two osmolytes: glycine betaine (TMG)and urea....
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The potential of imogolite nanotubes as (co-)photocatalysts: a linear-scaling density functional theory study
PublikacjaWe report a linear-scaling density functional theory (DFT) study of the structure, wall-polarization absolute band-alignment and optical absorption of several, recently synthesized, open-ended imogolite (Imo) nanotubes (NTs), namely single-walled (SW) aluminosilicate (AlSi), SW aluminogermanate (AlGe), SW methylated aluminosilicate (AlSi-Me), and double-walled (DW) AlGe NTs. Simulations with three different semi-local and dispersion-corrected...
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The electronic structure of p-xylylene and its reactivity with vinyl molecules
PublikacjaThe electronic states of p-xylylene molecule were described at the multi-configurational CASSCF/MRMP2 level of theory. The closed-shell singlet state representing the quinoidal p-xylylene molecule was pre-dicted to be the ground electronic state whereas the triplet (benzoidal) and the singlet open-shell states were found to be much higher in energy (by 159 and 423 kJ/mol, respectively, as found at the CASSCF(8,8)/6-31+G(d) level)....
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Enhanced photocatalytic properties of lanthanide-TiO2 nanotubes: An experimental and theoretical study
PublikacjaA series of Er-, Yb-, Ho-, Tb-, Gd-, Pr-TiO2 nanotubes (RE-NTs) was prepared via an electrochemical method. The as-prepared photocatalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV–vis absorption, scanning electron microscopy (SEM) and luminescent spectroscopy. The experiments demonstrated that toluene in the gas phase was successfully degraded under visible light (LEDs λmax = 465...
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Polymerization of chloro-p-xylylenes, quantum-chemical study
PublikacjaThe p-xylylene monomers of parylene N, C and D have similar high polymerization reactivity. For effective copolymerization processes this fact is basically a draw- back and for instance the copolymerization with styrene doesn't go at all (Corley et al. J Pol Sc 13(68):137156, 1954). Substitution of terminal hydrogen atoms by chlorine atoms reduces reactivity dramatically. 7,7,8,8-tetrachloro-p- xylylene and 2,5,7,7,8,8-hexachloro-p-xylylene...
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Deep eutectic solvents based highly efficient extractive desulfurization of fuels – Eco-friendly approach
PublikacjaThe developed process is based on alternative, green and cheap solvents for efficient desulfurization of fuels. Several deep eutectic solvents (DESs) were successfully synthesized and studied as extraction solvents for desulfurization of model fuel containing thiophene (T), benzothiophene (BT) and dibenzothiophene (DBT). The most important extraction parameters (i.e. kind of DES, DES: fuel volume ratio, hydrogen bond acceptor:...
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Extractive detoxification of feedstocks for the production of biofuels using new hydrophobic deep eutectic solvents – Experimental and theoretical studies
PublikacjaThe paper presents a synthesis of novel hydrophobic deep eutectic solvents (DESs) composed of natural components, which were used for removal of furfural (FF) and 5-hydroxymethylfurfural (HMF) from lignocellulosic hydrolysates. The main physicochemical properties of DESs were determined, followed by explanation of the DES formation mechanism, using 1H NMR, 13C NMR and FT-IR analysis and density functional theory (DFT). The most...
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The influence of the position of a chiral substituent on undecathiophene chain. A DFT study
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DFT-based prediction of reactivity of short-chain alcohol dehydrogenase
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Music Data Processing and Mining in Large Databases for Active Media
PublikacjaThe aim of this paper was to investigate the problem of music data processing and mining in large databases. Tests were performed on a large data-base that included approximately 30000 audio files divided into 11 classes cor-responding to music genres with different cardinalities. Every audio file was de-scribed by a 173-element feature vector. To reduce the dimensionality of data the Principal Component Analysis (PCA) with variable...
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Parallelization of large vector similarity computations in a hybrid CPU+GPU environment
PublikacjaThe paper presents design, implementation and tuning of a hybrid parallel OpenMP+CUDA code for computation of similarity between pairs of a large number of multidimensional vectors. The problem has a wide range of applications, and consequently its optimization is of high importance, especially on currently widespread hybrid CPU+GPU systems targeted in the paper. The following are presented and tested for computation of all vector...
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Application of Web-GIS for Dissemination and 3D Visualization of Large-Volume LiDAR Data
PublikacjaThe increasing number of digital data sources, which allow for semi-automatic collection and storage of information regarding various aspects of life has recently granted a considerable rise in popularity to the term “Big data”. As far as geospatial data is concerned, one of the major sources of Big data are Light Detection And Ranging (LiDAR) scanners, which produce high resolution three-dimensional data on a local scale. The...
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Analytical eco-scale for assessing the greenness of analytical procedures
PublikacjaWe propose the analytical eco-scale as a novel comprehensive approach to evaluating the greenness of analytical methodology. It is based on assigning penalty points to parameters of an analytical process that are not in agreement with the ideal green analysis. This approach compares different parameters and different steps of the analytical process. Traditional green chemistry metrics 9e.g. Atom Economy, E-factor and Reaction Mass...
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A method for counting people attending large public events
PublikacjaThe algorithm for people counting in crowded scenes, based on the idea of virtual gate which uses optical flow method is presented. The concept and practical application of the developed algorithm under real conditions is depicted. The aim of the work is to estimate the number of people passing through entrances of a large sport hall. The most challenging problem was the unpredicted behavior of people while entering the building....
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Can Historic Interiors with Large Cubature be Turned Acoustically Correct?
PublikacjaHistoric interiors with large cubature, such as reception, theatrical, and concert halls, need to be renovated periodically if they are to be preserved as cultural heritage for future generations. In such cases it is necessary to maintain appropriate balance between requirements imposed by heritage conservation authorities office which are usually being given a higher priority, applicable safety regulations, and the comfort of...
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Theoretical designing of selenium heterocyclic non-fullerene acceptors with enhanced power conversion efficiency for organic solar cells: a DFT/TD-DFT-based prediction and understanding
PublikacjaIn this study, we have designed and explored a new series of non-fullerene acceptors for possible applications in organic solar cells. We have designed four molecules named as APH1 to APH4 after end-capped modification of recently synthesized Y6-Se-4Cl molecule. Density functional theory and time dependent-density functional theory have been employed for computing geometric and photovoltaic parameters of the designed molecules....
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Generation of large finite-element matrices on multiple graphics processors
PublikacjaThis paper presents techniques for generating very large finite-element matrices on a multicore workstation equipped with several graphics processing units (GPUs). To overcome the low memory size limitation of the GPUs, and at the same time to accelerate the generation process, we propose to generate the large sparse linear systems arising in finite-element analysis in an iterative manner on several GPUs and to use the graphics...
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A novel (Ti/Ce)UiO-X MOFs@TiO2 heterojunction for enhanced photocatalytic performance: Boosting via Ce4+/Ce3+ and Ti4+/Ti3+ redox mediators
PublikacjaTitanium-substituted cerium-oxo-based UiO MOFs with terephthalate linkers modified by various groups (–Br, –NH2, –NO2) or their derivatives (N-heterocyclic or biphenyl groups) were combined with titanium dioxide in a multistep route to obtain a core-shell-like architecture. DFT simulations showed that Ce- and bimetallic Ti/Ce- MOFs exhibited different charge compensation. Extended characterization revealed the formation of heterojunctions between...
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Electrochemical, theoretical and surface physicochemical studies of the alkaline copper corrosion inhibition by newly synthesized molecular complexes of benzenediamine and tetraamine with π acceptor
PublikacjaTwo charge transfer complexes, namely [(BDAH)+(PA−)] CT1 [(BTAH)2+(PA−)2] and CT2 (BDAH = 1,2-benzenediamine, BTAH = 1,2,4,5-benzenetetramine, and PA− = 2,4,6-trinitrophenolate), were synthesized and fully characterized using various spectroscopic techniques. CT1 and CT2 were tested as inhibitors to effectively control the uniform and anodic corrosion processes of copper in an alkaline electrolyte (1.0 M KOH) using various electrochemical...
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Structural Insights into New Bi(III) Coordination Polymers with Pyridine-2,3-Dicarboxylic Acid: Photoluminescence Properties and Anti-Helicobacter pylori Activity
PublikacjaTwo novel coordination polymers, [Bi2(2,3pydc)2(2,3pydcH)2(H2O)]n(1) and {(Et3NH)2[Bi(2,3pydc)(2,3pydcH)Cl2]}n(2) were prepared using as a prolinker pyridine-2,3-dicarboxylic acid(2,3pydcH2). The obtained complexes were fully characterized by elemental analysis, TG/DTG, FT-IR,solid-state photoluminescence, DFT calculations and single-crystal X-ray diffraction. The obtainedcomplexes crystallized in the triclinicP-1 space group (1)...