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Search results for: crystal structure determination
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Porous structure of natural and modified clinoptilolites
PublicationOpisano wyniki badań struktury porowatej naturalnych zeolitów. W badaniach wykorzystano technikę SEM oraz wyznaczono izotermy procesu adsorpcji-desorpcji azotu w temperaturze 77 st. K.
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The structure, including stereochemistry, of levorin A1
PublicationThe constitution and stereostructure of levorin A1 1, an aromatic heptaeneantifungal antibiotic, was established on the basis of NMR studies, which contained DQFCOSY,ROESY, HSQC and HMBC experiments. Mycosamine moiety was used as an internalchiral probe to determine the absolute configuration of levorin A1 stereogenic centers: 13S,15R, 17S, 18R, 19S, 21R. The relative configuration of the remaining stereogenic centers wasassigned...
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Magnetism and structure ofLixCoO2and comparison toNaxCoO2
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Bulk properties and electronic structure of PuFeAsO
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The Farrow structure for the Hilbert transform filter
PublicationPrzedstawiono nową implementację cyfrowego filtru Hilberta, wykonaną w strukturze Farrowa. Jest to filtr zespolony, realizujący jednocześnie dwie różne operacje liniowe, wykonywane dotychczas za pomocą osobnych filtrów. Pierwsza z nich polega na standardowej filtracji hilbertowskiej. Tworzy ona zespolony "analityczny" odpowiednik rzeczywistego sygnału wejściowego. Drugą, osiąganą za pomocą prze-próbkowania ze współczynnikiem, w...
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Example of tension fabric structure analysis
PublicationThe aim of the work is to examine two variants of non-linear strain-stress relations accepted to description of architectural fabric. Discussion on the fundamental equations of the dense net model, used in description of coated woven fabric behaviour is presented. An analysis of tensile fabric structures subjected to the dead load and initial pretension is described.
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Bulk properties and electronic structure of PuFeAsO
PublicationW pracy zamieszczone wyniki badań krystalograficznych, pomiarów ciepła właściwego i podatności magnetycznej na nowym związku PuFeAsO. PuFeAsO jest antyferromagnetykiem z T_N = 50 K.
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Measures for Evaluation of Structure and Semantics of Ontologies
PublicationArtykuł przedstawia zagadnienie miar jakości ontologii ze szczególnym uwzględnieniem ich podziału na syntaktyczne (strukturalne) i semantyczne. Na tym tle przedstawione jest nowe podejście do pomiaru właściwości semantycznych ontologii bazujące na kartografii wiedzy.
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Structure and Randomness in Planning and Reinforcement Learning
PublicationPlanning in large state spaces inevitably needs to balance the depth and breadth of the search. It has a crucial impact on the performance of a planner and most manage this interplay implicitly. We present a novel method \textit{Shoot Tree Search (STS)}, which makes it possible to control this trade-off more explicitly. Our algorithm can be understood as an interpolation between two celebrated search mechanisms: MCTS and random...
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Structure of the Resource Theory of Quantum Coherence
PublicationQuantum coherence is an essential feature of quantum mechanics which is responsible for the departure between the classical and quantum world. The recently established resource theory of quantum coherence studies possible quantum technological applications of quantum coherence, and limitations that arise if one is lacking the ability to establish superpositions. An important open problem in this context is a simple characterization...
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FE simulations of a soil structure interface.
PublicationPrzedstawiono warunki brzegowe do opisu szorstkości ściany konstrukcji w kontakcie z gruntem. Wykonano doświadczenia i symulacje MES na bazie mikropolarnego prawa hipoplastycznego.
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Minimal parameter implicit solvent model for ab initioelectronic-structure calculations
PublicationAbstract - We present an implicit solvent model for ab initio electronic-structure calculations which is fully self-consistent and is based on direct solution of the nonhomogeneous Poisson equation. The solute cavity is naturally defined in terms of an isosurface of the electronic density according to the formula of Fattebert and Gygi (J. Comput. Chem., 23 (2002) 662). While this model depends on only two parameters, we demonstrate...
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Electronic structure and magnetism of samarium and neodymium adatoms on free-standing graphene
PublicationThe electronic structure of selected rare-earth atoms adsorbed on a free-standing graphene was investigated using methods beyond the conventional density functional theory (DFT+U, DFT +HIA, and DFT+ED). The influence of the electron correlations and the spin-orbit coupling on the magnetic properties has been examined. The DFT+U method predicts both atoms to carry local magnetic moments (spin and orbital) contrary to a nonmagnetic...
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Damaged plasticity model - seismic analysis of structure of the Petronas Twin Towers (Kuala Lumpur) in Malaysia
PublicationThe article presents numerical simulations for the modelling of seismic impact on the structure of Petronas Twin Towers (Kuala Lumpur) in Malaysia with application of two methods. The Response Spectrum method, in which a spectrum of the structure's responses to an earthquake's impact is generated and the Acceletogram (BETA) method, in which we generate dynamic load in the form of a diagram of the connection between acceleration...
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Effect of Individual Components of Lignocellulosic Biomass on Methane Production and Methanogen Community Structure
PublicationOne of the major factors that influences the economic feasibility of biogas production is the availability of digestible feedstocks. There is little research on the influence of the chemical composition of biomass on biogas synthesis, especially with regard to the content of lignocellulosic materials. Therefore, the aim of this study was to estimate how differences in the content of cellulose and lignin in lignocellulosic biomass...
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The Spatial Structure of Suburban Zones in Selected Entrepreneurship Nets of the Tricity Metropolitan Area
PublicationThe chapter describes spatial structures and forms of Polish suburban zones shown on the example of two selected towns in the Trojmiasto Metropolitan Area (TMA). The description of the spatial characteristics in the urban sprawl, with focus on the entrepreneurships nests is illustrated by the choice of typological features, such as: form, land use, density. Suburbanisation is described to be global, however one can observe individual...
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The structure of lead-silicate glasses and nanocomposites doped with iron oxide
Open Research DataThe structure of iron-doped glasses and glass-ceramics were studied. Samples has the composition of 50SiO2–(50−x)PbO–xFe2O3, where x=15, 20 and 25 (in mol%). All samples were prepared by the conventional melt quenching technique; the melting was conducted in air at 1623 K in alumina crucibles. The melts were poured on a brass plate preheated to 573...
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Leszek Ziemczonek dr
PeopleUniversity education 1973-1978 – Nicolaus Copernicus University in Toruń, University of Gdańsk in Gdańsk, Mathematical Physics, M. Sc. 1979 – Diploma of Postgraduate Studies, Pedagogics 1989 – Institute of Physics, Polish Academy of Sciences in Warsaw, Theoretical Physics, Ph. D. 2010-2012 – Diploma of Postgraduate Studies, Mathematics Training: · 09.1983 – Trieste (Italy) – International Centre for Theoretical Physics...
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Seasonal variability and morphological structure of bacteria in the Admiralty Bay (King George Island, Antarctic).
PublicationIntroduction: The aim of investigations was to state whether melting glaciers cause mass mortality of the sea stenohalyne organisms, what in consequence can lead to an increase of accumulation and growth of psychrophilic bacteria. It may be also that fresh melting water is unfavourable to the sea bacteria and front glacier's regions are not the areas of their intensive development. Methods: Field investigations were done in Admiralty...
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Forest habitat types in the State Forests and their age structure in the years 2014-2018
Open Research DataThe dataset contains data illustrating the area occupied by various types in the State Forests and their age structure over the years 2014-2018. It should be noted that this only concerns forests managed by the State Forests National Forest Holding. The average age is determined as a weighted average, with the area in individual age classes and subclasses...
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Forest habitat types in the State Forests and their age structure in the years 2019-2023
Open Research DataThe dataset contains data illustrating the area occupied by various types in the State Forests and their age structure over the years 2019-2023. It should be noted that this only concerns forests managed by the State Forests National Forest Holding. The average age is determined as a weighted average, with the area in individual age classes and subclasses...
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Determination of MDPBP in postmortem blood samples by gas chromatography coupled with mass spectrometry
PublicationMDPBP (1-(3,4-methylenedioxyphenyl)-2-(1-pyrrolidinyl)-1-butanone) is a new psychoactive substance sold on the black market. It has been a controlled drug of abuse in Poland and China since 2015 as some toxic and fatal cases connected with use of synthetic cathinone derivatives were observed. The fatal case outlined here concerns a 19 year-old man, who was found dead with an envelope containing white powder lying nearby the cadaver....
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Improving Output Performance of the Ultrasonic Multicell Piezoelectric Motor by Development the Multi-Rotor Structure
PublicationIn recent years, many researches have been carried out on piezoelectric multi-rotor structures. This paper describes the analysis, development and experimental process of an ultrasonic multi-cell piezoelectric motor using a multi-rotor structure. In this design, three independent cells have been integrated into a mechatronic system. Analytical model and finite element method are used for modal and dynamic analysis of the proposed...
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DETERMINATION OF THE AERODYNAMIC DRAG OF PNEUMATIC LIFE RAFTS AS A FACTOR FOR INCREASING THE RELIABILITY OF RESCUE OPERATIONS
PublicationEnsuring the safety of ship crews at sea is of the utmost importance. Life rafts are one of the basic components of any seagoing vessel and ensuring their stability is an important component of maritime research. This study concerns the determination of the aerodynamic drag coefficients of pneumatic life rafts in a full range of wind speed and directions. The drag coefficients are based on full-scale experimental studies and numerical...
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Determination of stepped plate thickness distribution using guided waves and compressed sensing approach
PublicationGuided waves recently have attracted significant interest as a very promising research area. The signals registered by a specially designed sensor network are processed to assess the state of the tested structure. Despite the constant development of novel damage detection algorithms employing guided waves, the phenomenon of wave propagation still needs detailed recognizing and understanding for the further progress of non-destructive...
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Analysis of pavement structure sensitivity to passage of oversized heavy duty vehicle in terms of bearing capacity
PublicationOversized heavy duty vehicles occur in traffic very rarely but they reach extremely high weights, even up to 800 tonne. The detrimental impact of these vehicles on pavement structure is much higher than in case of commercial vehicles that comprise typical traffic, thus it is necessary to assess the sensitivity of pavement structure to passage of oversized vehicles. The paper presents results of sample calculations of load equivalency factor...
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Analysis of the harmonic structure of the vowel /a/ taking into account the age and gender of the speaker
PublicationSound waves are disturbances propagating through an elastic medium that, upon reaching the ear, elicit auditory sensations. Sounds generated by the surroundings can be captured by a transducer (microphone), which transforms them into an electrical signal. The signal from the microphone is then transmitted to a computer, where software allows for the extraction and analysis of individual tones. This process enables the description...
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Smartphone-based digital image colorimetry for the determination of total capsaicinoid content in chili pepper extracts
PublicationA simple smartphone-based digital image colorimetry was proposed for the determination of total capsaicinoid content and the assessment of chili pepper pungency. The biobased solvent D-limonene was used for the first time to isolate analytes. Capsaicinoids were efficiently separated from chili pepper by solid-liquid extraction with D-limonene followed by partitioning of the analytes into the ammonium hydroxide solution to eliminate...
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The structure of lead-silicate glasses containing nanocrystallites of iron oxides
Open Research DataThe structure of iron-doped glasses and glass-ceramics were studied. Samples has the composition of (50 − 0.5x)SiO2–(50 − 0.5x)PbO–xFe2O3, where x = 2, 5, 10, 15, 20 and 25 (in mol%). All samples were prepared by the conventional melt quenching technique; the melting was conducted in air at 1623 K in alumina crucibles. The melts were poured on a brass...
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Determination of antifreeze substances in the airport runoff waters by solid-phase microextraction and gas chromatography–mass spectrometry method
PublicationA new method has been developed for the determination of antifreeze agents such as ethylene glycol (EG), propylene glycol (PG), and diethylene glycol (DEG) in the samples of airport runoff water. The method is based on headspace solid–phase microextraction (HS–SPME) of target analytes, which is coupled with gas chromatography–mass spectrometry (GC–MS). Until now, there was a lack of appropriate methodology for collecting reliable...
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Structure of the register of immovable monuments in terms of the number of monuments by voivodeship – comparison of 2003 and 2024
Open Research DataThe following dataset compares the structure of the register of immovable monuments in Poland regarding the number of monuments by voivodeship for 2003 and 2024. During these years, the number of monuments increased by more than 16,000.
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Novel 2019 coronavirus structure, mechanism of action, antiviral drug promises and rule out against its treatment
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Synthesis, structure and properties of novel poly(hydroxyurethane)s obtained by non-isocyanate route
PublicationNon-isocyanate polyurethanes (NIPUs) can be synthesized by polyaddition of five-membered bis(cyclic carbonate)s and primary diamines. NIPUs are an alternative for the commonly used (in the form of foams, elastomers, coatings or fibers) in the industry polyurethanes obtained using toxic and moisture sensitive diisocyanates, polyols and low-molecular weight chain extenders. The main aim of this work was to synthesize non-isocyanate...
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The structure of the data flow in integrated urban traffic management systems – the case of TRISTAR system
PublicationThe purpose of the article is to offer some insight into the data flow architecture in the Tri-City’s integrated traffic management system called TRISTAR. To that end selected elements of TRISTAR are identified and described as well as the structure for collecting and exchanging data within different sub-systems. Finally, the article highlights how the TRISTAR system can be extended by adding new elements and modules.
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The structure of lead-borate glasses containing nanocrystallites of iron oxides
Open Research DataThe structure of iron-doped glasses and glass-ceramics were studied. Glass samples of composition of xFe2O3–(100 − x)(B2O3–2PbO) (2.5 b x b 37, in mol%) were prepared by the conventional melt quenching technique. The melting was conducted in alumina crucibles at the temperature of 1523 K. The melts were poured on a preheated (573 K) brass plate and...
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The Effect of Calcination Temperature on Structure and Photocatalytic Properties of WO3/TiO2 Nanocomposites
PublicationSeries ofWO3/TiO2 nanocompositeswere obtained by hydrothermal method followed by calcination in the temperature range from 400∘C to 900∘C. The characteristics of photocatalysts by X-ray diffractometry (XRD), scanning electron microscope (SEM), and diffuse reflectance spectroscopy (DRS) showed that increasing the calcination temperature from 400 to 900∘C resulted in change of photocatalytic activity under UV-Vis light.Moreover,...
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Reduction of vibrations of steel structure models with Polymeric Bearings - experimental study
PublicationEarthquake-induced ground motions are the most severe and unpredictable threats to the structures all around the world. Therefore, designing earthquake protective systems has become an extremely challenging problem in civil engineering. Base isolation is one of the most popular and widely adopted methods of protecting structures against earthquake forces. The present paper reports the results obtained from the shaking table experimental...
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Determination of thiocyanate (biomarkers of ETS) and other inorganic ions in human nasal discharge samples using ion chromatography
PublicationEnvironmental tobacco smoke (ETS) is a mixture of air and tobacco smoke containing more than 4000 chemical substances. In view of the health risks of many of these substances, studies are needed to determine biomarkers of exposure to ETS constituents in people who actively or passively are exposed to the toxic compounds. The methodologies for determining most biomarkers from saliva, urine and blood samples are known, but methods...
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Determination of organophosphorus and organonitrogen pesticides in water samples
PublicationPesticides are among the most dangerous environmental pollutants because of their stability, mobility and long-term effects on living organisms. Their presence in sources of drinking water, essential to life, is a particular danger. In water, these compounds can undergo transformations, leading to the production of substances of even greater toxicity. Legal regulations are in force, stipulating the highest permissible level of...
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Review of the determination of pesticide residues in ambient air
PublicationW publikacji dokonano przeglądu najważniejszych metodyk oznaczania pozostałości pestycydów w powietrzu zewnętrznym. W publikacji przedstawiono także techniki używane do oznaczeń końcowych. Obecnie najpopularniejszą techniką oznaczeń końcowych jest chromatografia gazowa bądź cieczowa sprzężona ze spektrometrem mas.
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Analytical procedures for the determination of surfactants in environmental samples
PublicationBecause of their specific physical and chemical properties (amphiphilicity, solubility in polar and nonpolar liquids, ability to form micelles, adsorption at phase boundaries, low toxicity) surfactants (surface-active compounds) are widely applied in industry and in the household. As their applications are on a very large scale, it has become necessary to acquire a more detailed understanding of their environmental fate.In the...
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Determination of Failure Causes of a Steam Turbine Casing
PublicationThe paper presents results of research and failure analysis undertaken to determine failure causes of a steam turbine casing. After 130,000 hours of service the crack in a outer shell of the turbine casing was found. The inner shell of the casing was made of cast steel grade G21CrMoV5-7, and the outer shell of grade G20CrMo4-5. Following research were performed in order to determine causes of the casing failure: chemical analysis;...
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Modulation frequency constraints on wow and flutter determination
PublicationOpracowane wcześniej algorytmy do określania charakterystyki kołysania i drżenia dźwięku okazały się pomocne w rekonstrukcji rzeczywistych próbek dźwiękowych, jednakże przy ich opracowaniu nie określono przedziału częstotliwości modulujących, które mogą być przez nie śledzone. Prezentowany artykuł zawiera studium pozwalające wyznaczyć brakujące przedziały częstotliwości dla trzech algorytmów śledzących: przydźwięk sieciowy, pozostałość...
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Determination of optimal rotational speeds of circular saws
PublicationW pracy przedstawiono możliwości diagnostyczne stanowiska HewSaw do badania zachowania się pił w funkcji prędkości obrotowej piły. Wykazano, ze wyznaczone wartości prędkości optymalnych badanych pił leżą poniżej wartości zalecanych przez producenta. Praca z prędkościami wyższymi od optymalnych może prowadzić do zwiększenia strat materiałowych, a także stwarzać zagrożenia dla obsługi.
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Determination of the transverse resistance characteristics in railway track
PublicationW pracy przedstawiono problem oporów poprzecznych podsypki z punktu widzenia budowy, utrzymania oraz bezpieczeństwa w eksploatacji toru kolejowego. Zaprezentowano różne sposoby analitycznego podejścia do badanego zjawiska na przykładzie modeli matematycznych spotykanych w literaturze. Scharakteryzowano aktualny stan badań doświadczalnych związanych z oporami poprzecznymi. Omówiono różne sposoby prowadzenia takich badań w eksploatowanych...
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New approaches to chromatographic determination of lipophilicity of xenobiotics
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Recent Developments in Methods of Analysis for Fluoride Determination
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Comparision of Methods for Determination of Potential Evapotransportation (PET)
PublicationPotencjalna ewapotranspiracja (PET) jest traktowana jako indeks maksymalnej, możliwej ewapotranspiracji i jest wielkością często używaną w modelach hydrologicznych. W pracy porównano 4 modele obliczania PET: Konstantinowa, Turca, Thorntkwaita i Penmana. Są to metody o różnym stopniu dokładności. Przykładowe obliczenia przeprowadzono dla pomiarów ze stacji Bielnik, leżącej w pobliżu Gdańska.
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Some approaches to the determination of saw blade stiffness.
PublicationW nowoczesnych zakładach przerobu drewna obserwuje się tendencję do redukcji rzazu w celu ograniczenia strat surowca. Jednakże, cienkie piły są bardziej wrażliwe na odziaływanie sił odporowych (bocznych). Dlatego też, znajomość sztywności statycznej pozwala użytkownikowi prognozować zachowanie się piły podczas pracy. W pracy przedstawiono metodykę wyznaczania sztywności statycznej początkowej i roboczej pił trakowych oraz taśmowych....
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Determination and pathways of nitrogen during wastewater treatment.
PublicationŚcieki rafineryjne, farmaceutyczne oraz z przemysłu spożywczego charakteryzują się wysoką zawartością azotu amonowego. Biologiczne oczyszczanie ścieków przemysłowych zazwyczaj stwarza poważne problemy technologiczne. Azot zawarty w tego typu ściekach jest zawarty w aminach, amidach, czyli związkach, które wymagają wstępnego oczyszczania w celu zmniejszenia ich stężenia do wartości nie inhibujących reakcji biochemicznych oraz nitryfikacji....