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Wyniki wyszukiwania dla: chemical structure
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Anthropogenic enrichment of the chemical composition of bottom sediments of water bodies in the neighborhood of a non-ferrous metal smelter (Silesian Upland, Southern Poland)
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Synthesis, physical–chemical properties and in vitro photodynamic activity against oral cancer cells of novel porphyrazines possessing fluoroalkylthio and dietherthio substituents
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Synergistic effect of carbon fibers and carbon nanotubes on improving thermal stability and flame retardancy of polypropylene: a combination of a physical network and chemical crosslinking
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Isolation and characterization of stable nanofiber from turmeric spent using chemical treatment by acid hydrolysis and its potential as antimicrobial and antioxidant activities
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Influence of modification of the amino acids ionic liquids on their physico-chemical properties: Ionic liquids versus ionic liquids-supported Schiff bases
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The Effect of Mechanical Vibration during Transport under Model Conditions on the Shelf-Life, Quality and Physico-Chemical Parameters of Four Apple Cultivars
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Interspecific distribution and co-associations of chemical elements in the liver tissue of marine mammals from the Polish Economical Exclusive Zone, Baltic Sea
PublikacjaPrzeprowadzono analizy próbek wątroby ssaków morskich z Polskiej Strefy Ekonomicznej Morza Bałtyckiego w celu oznaczenia szerokiej gamy pierwiastków (mikro- i makroelementy) z wykorzystaniem takich technik analitycznych jak ICP-MS, ICP-AES oraz CV-AAS.Badano zależności pomiędzy zawartością poszczególnych pierwiastków a wiekiem, płcią, miejscem bytowania, sposobem odżywiania i gatunkiem ssaków.
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Chemical and biological characterization of Ocimum basilicum L. phenolic extract and essential oil derived through ultrasound and microwave-assisted extraction techniques
PublikacjaPlant-derived bioactive molecules are increasingly utilized in food processing as natural additives, driven by a growing interest in healthier lifestyles. This trend has spurred industries to reformulate products to meet the demands of health-conscious consumers. This study investigates the phenolic extract and essential oil of O. basilicum L. obtained via ultrasound-assisted extraction and microwave-assisted extraction, respectively. Characterization...
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Formaldehyde detection with chemical gas sensors based on WO3 nanowires decorated with metal nanoparticles under dark conditions and UV light irradiation
PublikacjaWe report results of formaldehyde gas (CH2O) detection under dark conditions and UV light irradiation with pristine tungsten trioxide nanowires (WO3 NWs) and metal nanoparticles decorated WO3 NWs gas sensing layers. The resistive layers were deposited by one step aerosol assisted chemical vapor deposition (AACVD) on commercial alumina substrates with 10-pair interdigitated platinum electrodes. The elaborated gas sensors, based...
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Analysis of features of stainless steels in dissimilar welded joints in chloride inducted corrosion
PublikacjaStainless steels of femtic-austenitic microstructure that means the duplex Cr-Ni-Mo steels, in comparison with austenitic steel includes less expensive nickel and has much better mechanical properties with good formability and corrosion resistance, even in environments containing chloride ions. Similar share of high chromium ferrite and austenite, which is characterized by high ductility, determines that the duplex steels have...
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Electronic structure calculations in electrolyte solutions: Methods for neutralization of extended charged interfaces
PublikacjaDensity functional theory (DFT) is often used for simulating extended materials such as infinite crystals or surfaces, under periodic boundary conditions (PBCs). In such calculations, when the simulation cell has non-zero charge, electrical neutrality has to be imposed, and this is often done via a uniform background charge of opposite sign (“jellium”). This artificial neutralization does not occur in reality, where a different...
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Binder-induced surface structure evolution effects on Li-ion battery performance
PublikacjaA comparative investigation on binder induced chemical and morphological evolution of Li4Ti5O12 electrodes was performed via X-ray photoemission spectroscopy, scanning electron microscopy, and electrochemical measurements. Composite electrodes were obtained using three different binders (PAA, PVdF, and CMC) with 80:10:10 ratio of active material:carbon:binder. The electrochemical performances of the electrodes, were found to be...
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Influence of synthesis conditions on glass formation, structure and thermal properties in the Na 2 O-CaO-P 2 O 5 system doped with Si 3 N 4 and Mg
PublikacjaOxynitride phosphate glasses and glass-ceramics were prepared using new synthesis routes for phosphate glasses. Materials were melted from pre-prepared glass samples in the system Na-Ca-P-O with addition of Mg and/or Si3N4 powders under different preparation conditions. The melting process was conducted at 1000–1500 °C either under air or nitrogen atmosphere to obtain materials with different nitrogen content. Their topography...
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Geometry optimization of steroid sulfatase inhibitors - the influence on the free binding energy with STS
PublikacjaIn the paper we review the application of two techniques (molecular mechanics and quantum mechanics) to study the influence of geometry optimization of the steroid sulfatase inhibitors on the values of descriptors coded their chemical structure and their free binding energy with the STS protein. We selected 22 STS-inhibitors and compared their structures optimized with MM+, PM7 and DFT B3LYP/6–31++G* approaches considering separately...
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Properties of nano-Fe3O4 incorporated epoxy coatings from Cure Index perspective
PublikacjaThe mission of an advanced epoxy-based nanocomposite coating is to provide a given substrate with protection against an unwelcome guest; e.g. corrosive molecules/media, environmental stress, flame, thermal degradation or microorganisms. In such systems, the degree to which superior properties can be guaranteed depends on the state of network formation in the epoxy in the presence of nanoparticles. For low-filled epoxy nanocomposite coatings,...
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Superconducting SrSnP with Strong Sn–P Antibonding Interaction: Is the Sn Atom Single or Mixed Valent?
PublikacjaThe large single crystals of SrSnP were prepared using Sn self-flux method. The superconductivity in the tetragonal SrSnP is observed with the critical temperature of ∼2.3 K. The results of a crystallographic analysis, superconducting characterization, and theoretical assessment of tetragonal SrSnP are presented. The SrSnP crystallizes in the CaGaN structure type with space group P4/nmm (S.G. 129, Pearson symbol tP6) according...
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Influence of Surface-Modified Montmorillonite Clays on the Properties of Elastomeric Thin Layer Nanocomposites
PublikacjaIn recent years, polyurethane nanocomposites have attracted more attention due to the massive demand for materials with increasingly exceptional mechanical, optical, electrical, and thermal properties. As nanofillers have a high surface area, the interaction between the nanofiller and the polymer matrix is an essential issue for these materials. The main aim of this study is to validate the impact of the montmorillonite nanofiller...
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Exploring of electronic structure of nitrogen-modified TiO2 photocatalysts through photocurrent and surface photovoltage studies
PublikacjaPrzeprowadzono pomiary fotonapięcia powierzchniowego i fotoprądu w obecności różnych reduktorów celem otrzymania eksperymentalnego potwierdzenia położenia pasma walencyjnego w strukturze elektronowej tlenku tytanu(IV) modyfikowanego azotem. Zaobserwowano silne sprzężenie poziomów N 2p i O 2p, którego konsekwencją jest powstanie nowego pasma walencyjnego
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Cubane Like Structure of a Silanethiol Primary Amine Assembly a Novel, Unusual Hydrogen Bond Pattern.
PublikacjaMetodą rentgenowskiej analizy strukturalnej wyznaczono struktury krystaliczne i cząsteczkowe trzech soli amoniowych: (t-BuO)3SiS(-)H3N(+)Bu-t, (i-PrO)3SiS(-)H3N(+)Bu-t i (t-BuO)3SiS(-)H3N(+)(CH2)2CH(CH3)2. Wszystkie trzy związki w ciele stałym tworzą tetramery w których atomy S i N wyznaczają w przybliżeniu naroża sześcianu. Trwałość tych agregatów, oprócz sił elektrostatycznego przyciągania, zapewnia sieć wiązań wodorowych N-H
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Prediction of Protein Structure by Template-Based Modeling Combined with the UNRES Force Field
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Nanoparticles preparation using microemulsion systems
PublikacjaMetallic nanoparticles become of current interests because they exhibit unique properties compared with those of metal atoms or bulk metal due to the quantum size effect and their large surface area, which make them attractive for applications in optics, electronics, catalysis biology and medicine. TiO2 has been used for environmental remediation purposes such as in the purification of water and air and also solar-to chemical energy...
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Correction: Synergistic effect of carbon fibers and carbon nanotubes on improving thermal stability and flame retardancy of polypropylene: a combination of a physical network and chemical crosslinking
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Design, Chemical Synthesis and Kinetic Studies of Trypsin Chromogenic Substrates Based on the Proteinase Binding Loop of Cucurbita maxima Trypsin Inhibitor (CMTI-III)
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Morpho-chemical characterization and source apportionment of potentially toxic metal(oid)s from school dust of second largest populous city of Pakistan
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Thermal and solutal performance of Cu/CuO nanoparticles on a non-linear radially stretching surface with heat source/sink and varying chemical reaction effects
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Chemical Reduction of 2,4,6-Tricyano-1,3,5-triazine and 1,3,5-Tricyanobenzene. Formation of Novel 4,4‘,6,6‘-Tetracyano-2,2‘-bitriazine and Its Radical Anion
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Impact of the Cultivation System and Pre-Sprouting of Selected Potato Cultivars on the Physico-Chemical Properties and Enzymatic Activity of Soil in the Conditions of Central-Eastern Poland
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Study of Phase Transitions Occurring in a Catalytic System of ncFe-NH3/H2 with Chemical Potential Programmed Reaction (CPPR) Method Coupled with In Situ XRD
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Evaluation of the Effect of Four Bioactive Compounds in Combination with Chemical Product against Two Spider Mites Tetranychus urticae and Eutetranychus orientalis(Acari: Tetranychidae)
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A dithiocarbamate/thiuram disulfide redox system. The electrochemical, strutructural and chemical characteristics.Zesz. Nauk. P. Gdań.2003 Chemia z.51[Rozprawa habilitacyjna]
PublikacjaKolokwium habilitacyjne 03.03.2004 r.
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Elucidation of chemical compounds in different extracts of two Lavandula taxa and their biological potentials: Walking with versatile agents on the road from nature to functional applications
PublikacjaDue to their health-promoting and nutraceutical properties, lavenders are frequently employed in the food and pharmaceutical industries. Here, we focused on investigate the chemical profile of hexane, MeOH, and water extracts of leaf, flower, and root of L. pedunculata and L. stoechas and to assess their antioxidant, enzyme inhibitory, and antibacterial properties. The highest total polyphenolic and flavonoids contents were recorded...
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Seashore sediment and water chemistry at the Admiralty Bay (King George Island, Maritime Antarctica) – geochemical analysis and correlations between the concentrations of chemical species
PublikacjaThis study covers water and sediment chemical characteristics by the western shore of Admiralty Bay (King George Island, Antarctica) in 2016. Chemical processes between sediment and water have been described based on the determination of ions, metals, non-metals, and TOC concentrations. Rock weathering is an important source of Fe, Ni, Co, Al in the seashore area. The PCA shows the impact of acidification in the release metals...
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Preliminary studies comparing the chemical composition of goitschiteand Saxonian succinite = Wstępne badania dotyczące porównania chemicznego składu goitszytu i sukcynitu saksońskiego
PublikacjaChemiczny skład goitszytu i sukcynitu saksońskiego porównano metodą spektroskopową (FTIR). Dalsza analiza została przeprowadzona z ekstraktów niepolarnych za pomocą chromatografii gazowej sprzężonej ze spektrometrią mas (GC-MS). Potwierdzono podobieństwo składu chemicznego bursztynu bitterfeldzkiego i sukcynitu z regionu Morza Bałtyckiego. Substancje zidentyfikowane w ekstrakcie goitszytu mogą sugerować jego genetyczne podobieństwo...
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Microbial and chemical quality assessment of the small rivers entering the South Baltic. Part II: Case study on the watercourses in the Puck Bay catchment area
PublikacjaDue to its location, Puck Bay is an area particularly vulnerable to pollution of anthropogenic origin. The aim of the study was to assess the water quality of small watercourses entering the inner part of Puck Bay. The paper presents the results of chemical and microbiological analyses of 10 rivers and canals at their estuaries located on the western shore of the internal Puck Bay. The following environmental parameters were analyzed:...
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Microbial and chemical quality assessment of the small rivers entering the South Baltic. Part I: Case study on the watercourses in the Baltic Sea catchment area
PublikacjaThe area of the Coastal Landscape Park (CLP) due to its location is extremely attractive touristic area. In the summer season, a significant increase in population density is observed, which influences surface water quality. Large numbers of tourists generate an increased amount of municipal wastewater, being treated in local treatment plants and discharged into rivers and streams. The paper presents preliminary research from summer...
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Sources and composition of chemical pollution in Maritime Antarctica (King George Island), part 2: Organic and inorganic chemicals in snow cover at the Warszawa Icefield
PublikacjaThe study area is located on King George Island, where 90% of the area is permanently glaciated. This study provides a comprehensive analysis of the inorganic and organic chemistry of snow cover in the icefield and a comparison against previous results obtained in fresh water. Snow samples were collected in the summer of 2017 in the Warszawa Icefield area. Sampling points are located along two transects: between the Arctowski Polish...
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Amphotericin B and Its New Derivatives - Mode of Action
PublikacjaAmphotericin B (AmB) is a well known antifungal and antiprotozoal antibiotic used in the clinic for several decades. Clinicalapplications of AmB, however, are limited by its nephrotoxicity and many other acute side effects which are not acceptable by patientswhen their life is not threaten. In order to improve the therapeutic index of this drug, lipid formulations have been introduced and manyefforts have been made to obtain less...
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Elastic polyurethane foams containing graphene nanoplatelets
PublikacjaElastic polyurethane foams were produced from two-component polyurethane systems (SPECFLEX NE 113 izocyjanian/NR 816 poliol system—SPC and Elastic MBMarket company system POLYOL ET MB 500/ISO ET MB 800—ET) by using a one-step method. The foams were a graphene nanoplatelets (GNP) in the amount ranging from 1 to 2 wt.%. The effect of the nanofiller on polyurethane matrix was determined by analyzing the chemical structure, static...
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IDENTIFICATION OF ODOR OF VOLATILE ORGANIC COMPOUNDS USING CLASSICAL SENSORY ANALYSIS AND ELECTRONIC NOSE TECHNIQUE
PublikacjaThe paper compares two methods of analysis of odour of volatile organic compounds: classical sensory analysis and electronic nose technique. Eight volunteers participated in the classical sensory analysis investigations, which lasted two weeks. An instrumental odour analysis involved a prototype of 6-sensor electronic nose designed by the authors. The research performed with this device provided higher reproducibility and reliability...
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Wpływ struktur wsparcia na efektywność nauczania języka pisanego w środowisku e-learningowym
PublikacjaThe process of knowledge and language skills development during an online course can be very effective if student engagement in learning is achieved. This can be attained by introducing general and specific support mechanisms prior to the commencement of the course and during it. The former relates to the technological aspect, that is to familiarizing students with the functionalities of the virtual learning environment they will...
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Properties of Composite Oxide Layers on The Ti13Nb13Zr Alloy
PublikacjaThe development of composite oxide layers on the Ti13Nb13Zr alloy, their structure and properties have been demonstrated. Two subsequent methods were applied to prepare the composite layers. During the first stage gas oxidation produced a solid oxide layer, and subsequently oxide nanotubes were produced by using an electrochemical method. Scanning electron microscopy (SEM), chemical analysis, energy dispersive X-ray spectroscopy...
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Quality Model for Integrated Security Monitoring and Control in Water Distribution Systems
PublikacjaThis article addresses the problem of drinking water distribution system (DWDS) security in the terms of water quality which in the era of terrorist threat is of high importance to the public. The contribution of this paper is the development of the so called security module to extend a multi-species water quality model. This gives an insight to the situation in DWDS not only under normal operational conditions but also in case...
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By-Products from Food Industry as a Promising Alternative for the Conventional Fillers for Wood–Polymer Composites
PublikacjaThe present paper describes the application of two types of food-industry by-products, brewers’ spent grain (BSG), and coffee silverskin (ŁK) as promising alternatives for the conventional beech wood flour (WF) for wood–polymer composites. The main goal was to investigate the impact of partial and complete WF substitution by BSG and ŁK on the processing, structure, physicochemical, mechanical, and thermal properties of resulting...
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Novel Cold Crucible Ultrasonic Atomization Powder Production Method for 3D Printing
Publikacja: A new powder production method has been developed to speed up the search for novel alloys for additive manufacturing. The technique involves an ultrasonically agitated cold crucible installed at the top of a 20 kHz ultrasonic sonotrode. The material is melted with an electric arc and undergoes pulverization with standing wave vibrations. Several different alloys in various forms, including noble and metallic glass alloys, were...
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Insights into Compatibilization of Poly(ε-caprolactone)-based Biocomposites with Diisocyanates as Modifiers of Cellulose Fillers
PublikacjaThis study aimed to analyze the impact of cellulose fillers’ modification with diisocyanates on the performance of composites based on the poly(ε-caprolactone) (PCL) matrix. Four most commonly used diisocyantes (isophorone, hexamethylene, toluene, and methylene diphenyl) were applied as modifiers of cellulose fillers (5 and 15 wt% per mass of filler). Modified fillers were introduced in the amount of 30 wt% into the PCL matrix....
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Recent advances in electrochemically surface treated titanium and its alloys for biomedical applications: A review of anodic and plasma electrolytic oxidation methods
PublikacjaNowadays, titanium and its alloys are widely used materials in implantology. Nevertheless, the greatest challenge is still its appropriate surface treatment in order to induce optimal properties, which facilitates formation of a permanent bond between the implant and human tissue. The use of electrochemical treatment such as anodic oxidation or plasma electrolytic oxidation allows for the production of porous coating that mimics...
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Insights into Seawater Biodegradation of Sustainable Mater-Bi/Poly(ε-caprolactone)-Based Biocomposites Filled with Diisocyanate-Modified Cellulose Particles
Publikacja: Due to rapid economic growth, the use of plastics in almost all areas of human life has significantly increased over recent decades, leading to massive pollution. Therefore, works dealing with sustainable and biodegradable polymer materials are vital now. Herein, sustainable MaterBi/poly(ε-caprolactone) (PCL)-based biocomposites, filled with diisocyanate-modified cellulose particles, were prepared and subjected to 12-week seawater...
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Evaluation of the Cathodic Electrodeposition Effectiveness of the Hydroxyapatite Layer Used in Surface Modification of Ti6Al4V-Based Biomaterials
PublikacjaThe important issue associated with the design and the fabrication of the titanium and titanium alloy implants is the increase of their biointegration with bone tissue. In the presented paper, the research results concerning the conditions used in the cathodic deposition of hydroxyapatite on the surface Ti6Al4V substrates primarily modified by the production of TiO2 nanoporous coatings, TiO2 nanofibers, and titanate coatings, are...
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Preparation and photocatalytic properties of BaZrO 3 and SrZrO 3 modified with Cu 2 O/Bi 2 O 3 quantum dots
PublikacjaIn this study, we report a novel method of BaZrO3 and SrZrO3 surface modification by two different types of quantum dots (QDs, Cu2O and Bi2O3), which improved the photocatalytic performance of the obtained materials under UV-Vis light irradiation. Pristine BaZrO3 and SrZrO3 were prepared by the hydrothermal method. The deposition of Cu2O- and Bi2O3-QDs was carried out by chemical reduction. The morphology of the nanoparticles was...
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APPLICATION OF CHEMOMETRIC ANALYSIS TO THE STUDY OF SNOW AT THE SUDETY MOUNTAINS, POLAND
PublikacjaSnow samples were collected during winter 2011/2012 in three posts in the Western Sudety Mountains (Poland) in 3 consecutive phases of snow cover development, i.e. stabilisation (Feb 1st), growth (Mar 15th) and its ablation (Mar 27th). To maintain a fixed number of samples, each snow profile has been divided into six layers, but hydrochemical indications were made for each 10 cm section of core. The complete data set was subjected...