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The influence of methods of potato weed control and meteorological conditions on shaping the tuber yield structure
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Gypsum dehydration in cement and its impact on air-void structure in air-entrained concrete
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Fiber - optic low-coherence tomography system for visualization of internal structure of ceramic materials
PublicationW artykule przedstawiono światłowodowy system dwuwymiarowej wizualizacji niejednorodnych struktur warstw ceramicznych. Omówiono projekt i fizyczną realizację układu wykorzystującego optyczną, niskokoherentną reflektometrię optyczną, która umożliwia niedestrukcyjne obrazowanie wewnętrznych struktur różnych materiałów. W pracy przedstawiono przykładowe wyniki pomiarów wewnętrznych warstw LSFO.
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Modulated photocurrents in a sandwich-cell structure: II. Influence of biasillumination intensity and carrier diffusion
PublicationPodano przybliżone wyrażenia opisujące modulowane fotoprądy (na podstawiemodelu wielokrotnego pułapkowania) w uwzględnieniem czynników wymienionych wtytule. Zbadano numerycznie ich wpływ na modulowane fotoprądy dla modelowychrozkładów pułapek. Otrzymano wzór - kryterium zaniedbania wpływu dyfuzji nafotoprądy.
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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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Structure recognition in MD-simulated materials: a case study of boroxyl rings in borate glasses
PublicationZanalizowano statystyczne właściwości geometryczne losowo deformowanej jednostki strukturalnej AC_3, gdzie trzy kationyC znajdują się w wierzchołkach trójkąta równobocznego, a anionA - w jego środku. W szczególności opisano rozkłady kątów AAA,ACA i CAA oraz dwóch estymatorów kształtu w funkcji amplitudydeformacji trójkąta. Wyniki analizy stochastycznej zastosowanodo ilościowej oceny stopnia nieuporządkowania w szkle B_2O_3,symulowanym...
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Synthesis and structure of Dicyclohexylammonium Tri-tert-pentoxysilanethiolate and 5-aminopentylammonium Tri-tert-pentoxysilanethiolate
PublicationTri-tert-pentoksysilanotiol reaguje z dicykloheksyloaminą i 1,5-diaminopentanem dając odpowiednie sole amoniowe. Sole te scharakteryzowano poprzez analizę elementarną, widma IR i NMR oraz metodą rentgenowskiej analizy strukturalnej. Są to pierwsze pochodne tri-tert-pentoksysilanotiolu, dla których wyznaczono strukturę krystaliczną.
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Influence of controlled crystallization and SrF2 content on the structure and properties of Eu3+ doped phosphate glasses
PublicationNew phosphate glasses and glass-ceramics P2O5–Bi2O3–K2O–Nb2O5-SrF2 doped with Eu were synthesized and studied in this work. The influence of the SrF2 content (0–15 mol%) and the parameters of the heat treatment on their structural and optical properties were investigated. For the above purpose, the structural characterization by FTIR spectroscopy and XRD measurements was carried out, which showed a significant effect of SrF2 on...
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Impact of steel grade on a ship colliding with an offshore wind turbine monopile supporting structure
PublicationOffshore wind power is experiencing rapid development around the world. The number of installations and their size is growing. Thousands of monopile support structures with diameters of 10 m and weights of 2000 tons will be installed in the coming years. Offshore wind power installations, often located close to the shore and shipping routes, pose a new challenge to ship safety. The study analyses the damages from an accidental...
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Amide/Amino-Based Functional Additives for Lubricants: Structure, Antimicrobial Activity and Wear Resistance
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Endophytic microbiota and ectomycorrhizal structure of Alnus glutinosa Gaertn. at saline and nonsaline forest sites
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New Content Based Image Retrieval database structure using Query by Approximate Shapes
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The partial-order tree: a new structure for indexing on complex attributes in object-oriented databases
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FE-investigations of micro-polar boundary conditions along interface between soil and structure
PublicationW artykule zaproponowano mikropolarne warunki brzegowe w strefie kontaktu materiału granulowanego ze ścianą konstrukcji. Warunki te umożliwiają wyznaczenie grubości strefy kontaktu w zależności od szorstkości ściany. Obliczenia wykonano przy zastosowaniu metody elementów skończonych i mikropolarnego modelu hipoplastycznego.
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Chalcogen bonding interactions in a series of aromatic selenocyanates
PublicationSelenium atoms in aromatic selenocyanates are characterized by the occurrence of two σ-holes, a stronger one in the prolongation of the NC–Se bond and a weaker one in the prolongation of the Ar–Se bond. The crystal structures of several bis(selenocyanato) derivatives, prepared by a method originally developed for ortho bis-substituted derivatives, illustrate very well this difference, with a short NC–Se⋯NC ChB interaction organizing...
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Dimeric structure of the N-terminal domain of PriB protein from Thermoanaerobacter tengcongensis solved ab initio
PublicationPriB is one of the components of the bacterial primosome, which catalyzes the reactivation of stalled replication forks at sites of DNA damage. The N-terminal domain of the PriB protein from the thermophilic bacterium Thermoanaerobacter tengcongensis (TtePriB) was expressed and its crystal structure was solved at the atomic resolution of 1.09 Å by direct methods. The protein chain, which encompasses the first 104 residues of the...
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Interplay between Aryl···Perfluoroaryl and Hydrogen Bonding Interactions in Cocrystals of Pentafluorophenol with Molecules of Trigonal Symmetry
PublicationCocrystals of seven star-shaped triaryl compounds with pentafluorophenol (pfp) were prepared and structurally characterized by the single-crystal X-ray diffraction method. Cocrystallization of pfp with planar (or almost planar) compounds gave six 3:1 molecular complexes with well-defined layered structures. The layers are composed of alternating pfp3 trimers, linked by hydrogen bonding, and triaryl molecules held together in planes...
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<i>N,N</i>'-diphenylthiourea acetone monosolvate
PublicationIn the title compound, C13H12N2S·C3H6O, the phenyl rings of the thiourea molecule are in syn and anti positions in relation to the C=S bond. Two molecules are connected by N-HS=C hydrogen bonds into a centrosymmetric dimer. An additional N-HO=C hydrogen bond to the acetone solvent molecule and some weak C-H interactions reinforce the crystal structure.
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Manifestation of Intermolecular Interactions in the IR Spectra of 2- and 4-Methylmethcathinones Hydrochlorides: DFT Study and Hirshfeld Surfaces Analysis
PublicationThis paper reports a Hirshfeld surfaces analysis of crystalline 2- and 4-methylmethcathinone (2-MMC and 4-MMC) hydrochlorides to analyze NH∙Cl and CH∙∙∙Cl intermolecular interactions and approve the formation of the NН2+–Cl– salt fragment in both 2-MMC∙HCl and 4-MMC∙HCl crystals. Two isomeric dimers were separated from the corresponding crystal packing to model IR spectra of the crystalline 2-MMC∙HCl...
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Experimental and theoretical investigation of conformational states and noncovalent interactions in crystalline sulfonamides with a methoxyphenyl moiety
PublicationFour sulfonamide derivatives with a methoxyphenyl moiety, namely N-{4-[(2-methoxyphenyl)sulfamoyl] phenyl}acetamide (1a), N-{4-[(3-methoxyphenyl)sulfamoyl]phenyl}acetamide (1b), 4-amino-N-(2- methoxyphenyl)benzenesulfonamide (2a) and 4-amino-N-(3-methoxyphenyl)benzenesulfonamide (2b), have been synthesized and characterized physiochemically by CHNS, MS, FT-IR, 1H NMR, 13C NMR, PXRD and TG methods. Crystal structures were determined...
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New heterometallic Co/Zn, Ag/Co, and Ag/Zn imidazolates: structural characterization and catalytic activity in the oxidation of organic compounds
PublicationNanocrystalline powders of monometallic and bimetallic imidazolates of Co, Zn, and Ag were produced by a reaction carried out in water. The powders were characterized by powder X-ray diffraction and the crystal structures of new compounds Ag2ZnIm4 and Ag2CoIm4 (Im = imidazolate) were solved. Heterometallic Co/Zn imidazolates showed the standard ZIF-8 crystal structure while Ag/Zn and Ag/Co systems were isostructural with the copper...
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Coordination polymers and molecular structures among complexes of mercury(II) halides with selected 1-benzoylthioureas
PublicationSix new 1-benzoyl-3-phenylthiourea and 1-benzoyl-3-(2-methylphenyl)thiourea complexes of mercury( II) were obtained in the reactions of the ligands with HgX2 in methanol (X = Cl, Br, I). Their structures, determined by single-crystal X-ray diffraction analysis, exhibit different stoichiometries and molecular organization. Coordination centers adopt more or less distorted tetrahedral geometry (five structures) or distorted trigonal...
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Studies on intercorrelation between selected persistent organic pollutants (POPs) and ions in sea water from the coastal zone of the Baltic Sea, Gdańsk Bay Region
PublicationMorze Bałtyckie jest zbiornikiem słonej wody a szacunkowy czas wymiany z innymi akwenami wynosi 25 lat. Woda morska jest zanieczyszczona wieloma nieorganicznymi oraz organicznymi substancjami. Opracowanie przedstawia wyniki badań monitoringowych oraz ocenę stanu zanieczyszczenia środowiska morskiego w południowej części Morza Bałtyckiego, w rejonie Zatoki Gdańskiej. W próbkach wody morskiej oznaczano: wielopierścieniowe węglowodory...
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Profesor Jan Czochralski – historia najwybitniejszego polskiego inżyniera
PublicationHistoria odkrycia metody wzrostu kryształów
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Luminescent, Scintillation, and Photoconversion Properties of Micro‐Pulling‐Down‐Grown Single Crystals of Ce 3+ ‐Doped Gd 3− x Lu x Al 5− y Ga y O 12 Garnets
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Catena-Poly[{[mu]-[eta]5:[eta]5-1-[2-(dimethylamino)ethyl-[kappa]N]cyclopentadienyl}-lithium(I)-([mu]-1,1,3,3-tetra-tert-butyltriphosphane-[kappa]3P2:P1,P3)lithium(I)]
PublicationThe title compound, [Li2(C9H14N)(C16H36P3)]n, is a by-product of the reaction of [Cp(C5H4CH2CH2NMe2)ZrCl2]n with tBu2P-P(SiMe3)Li in toluene. It is a coordination polymer composed of infinite chains running along [010]. One Li(I) atom is chelated by the cyclopentadienyl ring and and the N atom of the scorpionate ligand and a P atom, whereas the other Li(I) atom is coordinated by the backside of the cyclopentadienyl ring and two...
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Synthesis, Structure and Properties of Poly(ester-Urethane-Urea)s Synthesized Using Biobased Diamine
PublicationModern polymer science and technology is focused on the development of partial or fully green polymers. This focus is related to green chemistry trends, which propose using natural and renewable resources as monomers in the synthesis of polymers. In this study, biobased diamine was used as a chain extender of ester-urethane prepolymer. Obtained poly(ester-urethane-urea) contains 16 wt% of biobased diamine. There is mention of an...
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Local Structure and Stability of SEI in Graphite and ZFO Electrodes Probed by As K-edge Absorption Spectroscopy
PublicationThe evolution of the solid electrolyte interphase (SEI) during the first Li uptake in advanced Li-ion electrodes is studied by X-ray absorption spectroscopy (XAS). The As atoms present in the electrolyte solution were used as a local probe for monitoring the SEI growth on different electrodes. High-quality As K-edge spectra were collected in fluorescence mode for a set of graphite and carbon-coated ZnFe2O4 electrodes. XAS measurements...
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Fe local structure in Pt-free nitrogen-modified carbon based electrocatalysts: XAFS study
PublicationThe paper presents a new results on the bonding environment (coordination number and geometry) and on oxidation states of Fe in nitrogen-modified Fe/C composites used as Pt-free catalysts for oxygen reduction in Direct Hydrogen Fuel Cells. Starting from glucose or fructose, two catalysts displaying different electrochemical performance were prepared and studied in the form of pristine powder and thin catalytic layer of electrode...
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Chemical structure, thermal and mechanical characterization of bio-based polyurethane composites filled with microcrystalline cellulose
PublicationOver the past several decades, the interest in replacing the synthetic components used in the production of polymers and composites with their natural counteparts has been growing. Biocomposites belong to the group of materials produced with the use of renewable raw materials. There has been a recent surge of interest in the industrial applications of composites containing natural fibres reinforced with biopolymers. Biopolymers...
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Structure and thermoelectric properties of Bi–Te alloys obtained by novel method of oxide substrates reduction
PublicationA novel method of thermoelectric materials fabrication has been developed. Oxide reagents have been melted at high temperature in air, quenched, milled to powder and reduced in hydrogen to form Bi–Te alloys. Structural and thermoelectric properties of samples have been investigated depending on initial composition and temperature of reduction process. Sample 25Bi2O3–75TeO2 reduced at 340 °C for 10 h has been found to be a p-type...
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Synthesis, Molecular Structure, Metabolic Stability and QSAR Studies of a Novel Series of Anticancer N-Acylbenzenesulfonamides
PublicationA series of novel N-acyl-4-chloro-5-methyl-2-(R1-methylthio)benzenesulfonamides 18–47 have been synthesized by the reaction of N-[4-chloro-5-methyl-2-(R1-methylthio) benzenesulfonyl]cyanamide potassium salts with appropriate carboxylic acids. Some of them showed anticancer activity toward the human cancer cell lines MCF-7, HCT-116 and HeLa, with the growth percentages (GPs) in the range from 7% to 46%. Quantitative structure-activity relationship...
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Eu3+ doped tellurite glass ceramics containing SrF2 nanocrystals: Preparation, structure and luminescence properties
PublicationEu3+ doped tellurite glass ceramics containing SrF2 nanocrystals were prepared using melt quenching technique and subsequent heat treatment of glass in 370 °C for different time periods. Thermal properties of glass matrix have been determined based on DSC measurements. XRD and XPS results confirmed formation of SrF2 nanocrystals in glass matrices after annealing at 370 °C. FTIR studies revealed absorption bands in the range of...
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UNRES server for physics-based coarse-grained simulations and prediction of protein structure, dynamics and thermodynamics
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Theoretical study of the structure, energetics and vibrational frequencies of water-acetone and water-2-butanone complexes
PublicationKompleksy acetonu i 2-butanonu z 0-2 cząsteczkami wody połączonymi wiązaniem wodorowym z tlenem karbonylowym zbadano z wykorzystaniem teorii funkcjonału gęstości (DFT) na poziomie B3LYP/6-311++G(d,p). Obliczenia w fazie gazowej uzupełniono o optymalizacje w otoczeniu rozpuszczalnika, symulowanego za pomocą modelu polaryzowalnego kontinuum (PCM). Częstości drgań oscylacyjnych otrzymane na podstawie zależności empirycznej sa zgodne...
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Cast aluminium matrix composites modified with using FSP process – Changing of the structure and mechanical properties
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Influence of the preparation method and aluminum ion substitution on the structure and electrical properties of lithium–iron ferrites
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Short review on the design and application of fractionl delay Hilbert transform filter using Farrow structure
PublicationThis paper is treated as a brief summary of our hitherto research on the design and utilization of the FDHTF, particularly in the sub-samole delay estimator.
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Assessment of operation of energy system of serial reliability structure on the example of ship main propulsion system
PublicationW artykule przedstawiono rozwinięcie znanej metody oceny działania systemu energetycznego, zastosowanej w odniesieniu do głównego układu napędowego statku. Według tej interpretacji działanie może być przedstawiane jako wielkość fizyczna. W tym aspekcie, na podstawie wybranego podsystemów funkcjonalnego statku, oceniono jej przydatność do opisu własności niezawodnościowych tego systemu. W analizie zastosowano teorię procesów Poissona,...
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Emplying set of experience knowledge structure and decisional DNA to enhance industrial design: conceptual approach
PublicationZaprezentowano koncepcje wspomagania projektowania przemyslowego przy pomocy nowoczenego podejscia do reprezentacji wiedzy w postaci SOEKS oraz Decyzyjnego DNA
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Enhancing set of experiance knowledge structure (SOEKS) with w nearest neighbour algorithm Relief-F
PublicationPrzedstawiono koncepcje uzupelnienia i wpsomagania struktury wiedzy opartej na SOEKS przy pomocy algorytmu przypisujacego wagi atrybutow.
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Hunting for the Magnesium(I) Species: Formation, Structure, andReactivity of some Donor-Free Grignard Compounds
PublicationMagnesium bromide radicals have to be prepared as high-temperature molecules and trapped as a metastable solution because a seemingly simple reduction of donor-free Grignard compounds failed. However, the essential role of magnesium(I) species during the formation of Grignard compounds could be demonstrated experimentally.
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Behaviour of Colliding Multi-Storey Buildings under Earthquake Excitation Considering Soil-Structure Interaction
PublicationThis paper investigates the coupled effect of the supporting soil flexibility and pounding between neighbouring, insufficiently separated buildings under earthquake excitation. Two adjacent three-storey structures, modelled as inelastic lumped mass systems with different structural characteristics, have been considered in the study. The models have been excited using the time history of the Kobe earthquake of 1995. A nonlinear...
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Revised structure of the repeating unit of the O-specific polysaccharide from Azospirillum lipoferum strain SpBr17
PublicationO-polisacharyd otrzymany poprzez delikatną kwasową hydrolizę lipopolisacharydu wyizolowanego z Azospirillum lipoferum SpBr17 był badany metodami spektroskopii NMR jak również metodą analizy metylacyjnej połączonej z elektroforezą SDS-PAGE. Stwierdzono, że nie jest on liniowym homopolimerem złożonym wyłącznie z (1->3) [alfa]-glikozydowo połączonych cząsteczek L-ramnopiranozy (jak proponowano wcześniej) lecz sekwencją kolejnych bloków...
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Structure and superconductivity of VN-SiO2 films obtained by thermal nitridation of sol-gel derived coatings
PublicationPraca prezentuje wyniki badań strukturalnych oraz właściwości nadprzewodzących cienkich warstw xVN-(100-x)SiO2, gdzie x = 90, 80, 70, 60 mol%. Warstwy zostały wykonane metodą termicznego azotowania z użyciem amoniaku cienkich warstw tlenkowych otrzymanych metodą zol-żel. Badania struktury przeprowadzono metodami XRD oraz XPS, natomiast właściwości nadprzewodzące badano metodą MMMA. Właściwości nadprzewodzące warstw zależą zarówno...
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Green thermoplastic poly(ether-urethane)s – synthesis, chemical structure and selected properties investigation
PublicationThis work aimed to characterize the effect of the monomers chemical structure on the selected properties of the green thermoplastic poly(ether-urethane)s. During synthesis two types of polyether biopolyols, 4,4′-diphenylmethane diisocyanate and bio-based 1,3-propanediol were employed. Materials were synthesized with the use of two step method and two different prepolymers, which were mixed together in equimolar quantities. Obtained...
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Multiparameter sensitivity analysis of a GFRP composite footbridge of a sandwich structure and U-shaped cross-section
PublicationThe paper deals with multiparameter sensitivity analysis of a composite footbridge. A shell‐like structure is 14.5 m long shows U‐shaped cross‐section and inner service dimensions 1.3 × 2.5 m. Glass fiber reinforced polymer GFRP laminate constitutes faces of a sandwich structure while PET foam received from recycled bottle builts a core. The structure was divided into 285 independent areas where the thickness of laminates and stiffness...
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The Morphology, Structure, Mechanical Properties and Biocompatibility of Nanotubular Titania Coatings before and after Autoclaving Process
PublicationThe autoclaving process is one of the sterilization procedures of implantable devices. Therefore, it is important to assess the impact of hot steam at high pressure on the morphology, structure, and properties of implants modified by nanocomposite coatings. In our works, we focused on studies on amorphous titania nanotubes produced by titanium alloy (Ti6Al4V) electrochemical oxidation in the potential range 5–60 V. Half of the...
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Structure, luminescent properties and FDTD simulation of TeO2-BaO-Bi2O3-Ag:Ln3+ glass-ceramics system
PublicationTeO2-BaO-Bi2O3-Ag glass systems (TBB) co-doped with terbium and europium ions have been successfully synthesized through conventional melt-quenching technique. Heat treatment procedure at 350 °C has been conducted in order to synthesize silver nanoparticles embedded in TBB glass matrix. Structural measurements involved XRD studies that revealed no crystallization of glass structure after heat treatment at elevated temperatures....
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Assessment of technical condition and repair of steel structure elements on the example of fire damage in a warehouse building
PublicationThe paper analyses a case study on the structural assessment of warehouse building partially damaged by fire caused by external source (fire of lorries close to the building). The authors focus on the site investigations and laboratory test results prior to assessing actual condition of the structural elements. Both strengthening concept and repair procedure of a steel column are addressed here. A short literature survey in the...