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Environmental impact and industrial development of biorenewable resources for polyurethanes
PublikacjaPolyurethanes are among the most developed types of polymers. They are produced from the three primary components, i.e., polyols, low-molecular-weight glycols used as chain extenders, and diisocyanates. Until recently, all these substrates have been obtained via petrochemical processes. A decrease in petroleum-based resources and new ecological trends in chemistry, chemical technology, and materials engineering have generated increasing...
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EVALUATING THE INFLUENCE OF BENDING STRESS ON A 1H18N9 STEEL SHAFT WEAR PROCESS IN A WATER LUBRICATED SLIDING BEARING WITH A RUBBER BUSHING
PublikacjaThe issue of excessive wear of shaft journals co-working with a rubber bearing has been unexplained so far. Premature and sometimes very intensive wear of ship sliding bearings in water conditions is the reason for carry out very expensive and more frequent than expected repairs. The authors (E. Piątkowska, W. Litwin) made an attempt to find a case that influences the value of this wear described in the paper “Attempt at Evaluating...
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Comparative wear test of journal sliding bearings with sintered bronze and Babbitt alloy bushes lubricated by environmentally acceptable/adapted lubricants (EAL)
PublikacjaA growing awareness of the negative effects of mineral oils on the natural environment has resulted in the introduction of new regulations related to environmental protection. One of these regulations requires the use of environmentally acceptable/adapted lubricants (EAL) to lubricate marine main shaft bearings, in place of the mineral lubricating oils that have been used for decades. Classification Societies, which supervise...
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Deposition and growth of thin ceramic films
Publikacja: Thin ceramic films play an important role in modern technology. One of the more utilized methods of deposition of ceramic films is spin coating. In this paper we investigate optimal deposition parameters for LaNi0.6Fe0.4O3−δ thin layers spin coated from a polymeric precursor. The quality of the obtained layers is checked using scanning electron microscopy. Additionally, we investigate the growth of grains in ceramic films annealed at...
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Functionalized polyolefins, synthesis application and industrial relevance
PublikacjaPolymers play a key role in our modern life full of technical advances and a continuous request for new materials with tailored properties for a low price. Their excellent mechanical properties, good processability, chemical stability and low price make polyolefins the polymers of choice for most commodity and some more specialized applications. As a result, polyolefins account for over 65% of the total world demand of plastic...
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Crystal and electronic structures of Ni(II) silanethiolates containing flexible diamine ligands
PublikacjaFive nickel(II) complexes containing aliphatic diamines and tri-tert-butoxysilanethiolate ligand have been synthesized for the purpose of studying their structural, spectral (IR, UV–Vis, HF EPR) and thermal properties. Complexes (1)–(5) have been prepared in high yield by reactions of [Ni{SSi(OtBu)3}2(NH3)(H2O)] with 1.3-propanediamine (L1), 1,6-hexanediamine (L2), or 1,7-heptanediamine (L3). The X-ray structures were determined...
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Enhanced aging resistance of poly(ε-caprolactone)/brewers’ spent grain composites
PublikacjaThe presented paper investigated the influence of brewers’ spent grain (BSG) extrusion pa-rameters on the photo-oxidative resistance of poly(ε-caprolactone)-based wood polymer composites. Filler samples characterized by the higher melanoidin content were more efficient in hindering of poly-mer degradation, inhibiting the decomposition of the polymer amorphous phase. As aresult, deteriora-tion of mechanical performance was limited,...
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Eksperymentalna analiza współczynników oporów lokalnych dla wybranych kształtek i złączek w systemach rur wielowarstwowych
PublikacjaArtykuł poświęcony jest analizie wartości współczynników oporów lokalnych dla wybranych kształtek i złączek pracujących w instalacjach z rur wielowarstwowych z tworzyw sztucznych. Badaniom poddano elementy o średnicach DN16, DN20, DN25, powszechnie wykorzystywane we współczesnych instalacjach sanitarnych. W pracy przedstawiono wybrane wyniki badań laboratoryjnych (dla rozszerzeń, kolanek i trójników) oraz ich porównanie z wartościami...
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Measurements of guided wave propagation in CFRP/steel adhesive joints obtained by scanning laser vibrometry
Dane BadawczeThe DataSet contains guided wave signals measured in adhesive joints of steel plates (steel of type S355 with a thickness of 11.9 mm ) and carbon fibre reinforced polymer (CarboDur S1012 with a thickness of 1.24 mm). The samples were as follows: #0 – intact; #1 – 10% disbond; #2 – 20% disbond; #3 – 50% disbond; #4 – 80% disbond; #5 – 100% disbond.
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Simultaneous determination of Na+, K+, Ca2+, Mg2+ and Cl- in unstimulated and stimulated human saliva using all solid state multisensor platform
PublikacjaHuman saliva is one of the body fluids which collection method is relatively simple and non-invasive. The article is dedicated to assess concentration (activity) of Na+, K+, Ca2+, Mg2+ and Cl- in fresh, unstimulated or stimulated human saliva samples using single solid contact ion-selective electrodes with conventional reference electrode and self-made multisensor platform (MP) equipped with ion-selective membranes for Na+, K+,...
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Turmeric nanofiber-encapsulated natural product formulation act as a phytogenic feed additive—A study in broilers on growth performance, biochemical indices of blood, and E. coli in cecum
PublikacjaA phytogenic feed additive (PFA) formulation was prepared with bioactive molecules—curcuminoids, gingerol, and carvacrol by encapsulating in nanofiber isolated from turmeric spent (turmeric nanofiber, TNF). This formulation was completely characterized by scanning electron microscope, ultra performance liquid chromatography, and gas chromatography and evaluated for its efficacy. PFA-encapsulated TNF (PFA@TNF) considerably increased...
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Molecular dynamics simulations of the growth of poly (chloro-para-xylylene) films.
PublikacjaParylene C, poly(chloro-para-xylylene) is the most widely used member of the parylene family due to its excellent chemical and physical properties. In this work we analyzed the formation of the parylene C film using molecular mechanics and molecular dynamics methods. A five unit chain is necessary to create a stable hydrophobic cluster and to adhere to a covered surface. Two scenarios were deemed to take place. The obtained results...
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Analysis of AC/DC/DC Converter Modules for Direct Current Fast-Charging Applications
PublikacjaThe paper is a comprehensive laboratory comparison study of two galvanic isolated solution off-board battery chargers: (1) Si-based cost-effective case, and (2) SiC-bidirectional ready for vehicle to grid concept case. All circuits are modular, and in both cases the DC/DC converter can be replaced according to the end user requirements (the coupled transformer remains the same and is constructed based on 12xC100 cores to avoid...
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Degradibility in vitro of polyurethanes based on synthetic atactic poly[)R,S)-3-hydroxybutyrate
PublikacjaThe aim of the paper was to determine the degradibility of aliphatic polyurethanes in hydrolytic and oxidative solutions. DSC, GPC, density, polymer surface morphology were studied.
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Extremophile Deinococcus geothermalis as potential source of proteolytic enzymes
PublikacjaAmong many extremozymes, thermophilic enzymes have attracted most attention during the past four decades. Such enzymes are of considerable industrial and biotechnological interest due to the fact that the enzymes are better suited for harsh industrial processes. There are many advantages of conducting industrial processes at high temperature, such as the increased solubility of many polymeric substrates, resulting in decreased...
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Salicylaldimine-based receptor as a material for iron(III) selective optical sensing
Publikacjaα,α-Bis(salicylimino)-m-xylene (L) was prepared using both conventional and microwave-assisted procedure. The compound exhibits ability to colorimetric recognition of iron(III) ions in aqueous environment, what is shown by significant color change from yellow to purple. In DMSO : water (9:1 v/v) solvent system receptor creates with iron(III) cations complexes of 2:1 stoichiometry (L:Fe3+) with stability constant (log K) 7.54±0.21....
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Membranes for toxic- and heavy-metal removal
PublikacjaSince time ago, membranes have greatly attracted the attention of researchers for different types of water-treatment applications, such as wastewater treatment, water purification, removal of microorganisms, chemical compounds, and heavy metals. Nowadays, one of the current challenges of research community definitely deals with the removal of toxic and heavy metals from water. In this regard, the current chapter provides enough...
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Studies on applicability of new solid-phase microextraction and determination of short - chain monocarboxylic acids
PublikacjaA convenient approach to monitor the short-chain monocaroboksylic acids (SCAMs) in different samples is gas chromatography (GC) preceded by sample preparation based on solid-phase microextraction (SPME). The fiber with polar coatings were used to extract the SCAMs from headspace of liquid and solid samples. Recently polimeric ionic liquid (PIL) fiber coatings have been proposed to extract volatile organic compounds, minly polar...
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Underwater Wet Repair Welding of API 5L X65M Pipeline Steel
PublikacjaThis paper presents results of the research of effect of polymer insulation of pipeline made of API 5L X65M steel as well as underwater wet welding parameters on properties of joints made by covered electrodes. Effect of heat input on structure and hardness of joints during repair of underwater pipeline was analyzed. Welding defects like microcracks, micro-lacks of fusion, slag inclusions, as well as HAZ hardness increase over...
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The influence of 4,4'-bis(6-hydroxyhexoxy)biphenyl moieties on properties of polyurethanes based on 4,4'-methylenebis(cyclohexyl isocyanate)
PublikacjaZsyntetyzowano dwie serie poliuretanów z 4,4'-bis(6-hydroksyheksyloksy)bifenylu (BH6), poliadypinianu 1,6-heksylenu i diizocyjanianu 4,4'-dicykloheksylometanu o udziałach izomeru trans, wynoszącym odpowiednio 16 i 46%. Badano wpływ udziału wagowego (u) małocząsteczkowego diolu(BH6)w odniesieniu do sumy mas komonomerów diolowych, na właściwości uzyskanych poliuretanów metodami DSC, DTA, TGA, mikroskopii polaryzacyjnej, WAXS, DMTA...
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Thin-layer synthesized acrylamide copolymers modified with montmorillonite. Flocculation efficiency evaluation
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Esterification of starch with sodium selenite and selenate
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Carboxymethyl cellulose–gelatin complexes
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Electrosynthesis of potato starch–whey protein isolate complexes
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Spectroscopic insight into supramolecular assemblies of boric acid derivatives and β-cyclodextrin
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Novel hydrophilic carboxymethyl starch/montmorillonite nanocomposite films
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Carboxymethylated starch and cellulose derivatives-based film as human skin equivalent for adhesive properties testing
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Glycoside hydrolase (PelAh) immobilization prevents Pseudomonas aeruginosa biofilm formation on cellulose-based wound dressing
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Synthesis, chemical structure and properties of cross-linked poly(esterourethanes) based on unsaturated oligo(alkyleneester)diols
PublikacjaW pracy przedstawiono wyniki badań struktury chemicznej i właściwości nienasyconych oligo(alkilenoestro)dioli oraz syntetyzowanych z ich udziałem poli(estrouretanów). Strukturę oligomeroli oraz poliuretanów ustalono w oparciu o wyniki badań FTIR, NMR, analizę elementarną. Właściwości poli(estrouretanów) określono przez pomiary stabilności termicznej, analizę termomechaniczną oraz obliczenia ciężaru cząsteczkowego łańcuchów polimerowych...
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Effect of preparation method on the properties of potato starch acetates with an equal degree of substitution
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All-natural bio-plastics using starch-betaglucan composites
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Properties of retrograded and acetylated starch produced via starch extrusion or starch hydrolysis with pullulanase
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Selected properties of acetylated adipate of retrograded starch
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Patentology of chitinous biomaterials. Part I: Chitin
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Bacterial cellulose yield increased over 500% by supplementation of medium with vegetable oil
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Superabsorbent crosslinked bacterial cellulose biomaterials for chronic wound dressings
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Correlation between type of alkali rinsing, cytotoxicity of bio-nanocellulose and presence of metabolites within cellulose membranes
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Evaluation of usefulness of 2DCorr technique in assessing physicochemical properties of bacterial cellulose
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Microwave-assisted silication of potato starch
PublikacjaSilication of potato starch was performed by microwave irradiation and convectional heating of starch with sodium metasilicate. The study has shown that microwaves offered more selective silication thanconvectional heating. Depending on the dose of metasilicate products of either monoesterification or crosslinking esterification were formed. Increase in the amount of the silicating agent favoured crosslinking of starch. In the...
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Stability and physicochemical properties of model salad dressings prepared with pregelatinized potato starch
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Microwave-assisted preparation of potato starch silicated with silicic acid
PublikacjaApplication of microwave irradiation for the silication of granular potato starch with silicic acid, and the properties of silicated starch were investigated. Potato starch was esterified on 20 min microwave irradiation of starch with silicic acid, applying the power of 450 or 800Wand, for comparison, on 120 min convectional heating of the reagent blend at 100 ◦C. The degree of esterification and the reaction efficiency did not...
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Microwave-assisted synthesis of zinc derivatives of potato starch
PublikacjaZincatated potato starch was prepared in a solid-state, microwave-assisted reaction using generated in situ sodium tetrahydroxozincate [Na2Zn(OH)4]. For comparison, zincatation of starch was also carriedout on convectional heating. Depending on the irradiation conditions, the products of either mono- or crosslinking esterification were formed. Higher power applied at shorter exposition offered products ofmonoesterification, and...
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Rigid polyurethane foams modified with ground tire rubber - mechanical, morphological and thermal studies
PublikacjaRigid polyurethane foams, prepared by a single step method, were modified with the two types of ground tire rubber particles, i.e. untreated and thermo-mechanically reclaimed by using a co-rotating twin screw extruder. The foaming process as well as the structure and the physical, mechanical and thermal properties of the resulting foams were investigated. The presence of ground tire rubber decreased the velocity of polymerization....
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Foamed Polyurethane Composites With Different Types of Ash – Morphological, Mechanical and Thermal Behavior Assessments
Publikacjancorporation of two types of ash particles into flexible polyurethane foams has been investigated, wood ash from gasification process and fly ash resulting from coal burning in power plant. Samples were modified with 5, 10 and 15 wt% of fillers. Structure, mechanical and thermal properties of obtained foams were investigated. Incorporation of both types of ash particles resulted in materials showing...
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Investigation of an elutable N-propylphosphonic acid chitosan derivative composition with a chitosan matrix prepared from carbonic acid solution
PublikacjaPorous chitosan composites using CO2 dissolution procedure and including water soluble N-propylphosphonic chitosan derivative (p-CHI) were obtained and characterized. In contrast to the control material, composites containing modified chitosan distinguished by a rapid moisture absorption and good adhesion to the skin. The FTIR analysis confirmed the presence of propylphosphonic group in the structure of the polymer. The porosity...
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Preparation and characterization of genipin cross-linked porous chitosan–collagen–gelatin scaffolds using chitosan–CO2 solution
PublikacjaNovel porous scaffolds composed of chitosan, collagen and gelatin were prepared by the multistep procedure involving final freeze-drying and characterized. To eliminate the need for residual acid removal from the material after drying, carbon dioxide saturation process was used for chitosan blend formulation. The use of CO2 for chitosan dissolution made the scaffold preparation process more reproducible and economically sustainable....
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Novel Biodegradable Potato Starch-based Compositions as Candidates in Packaging Industry, Safe for Marine Environment
PublikacjaAbout 70 % of our planet’s surface is covered by seas and oceans to which even 10 million tons of waste go every year. It makes these places the largest global landfills, containing up to 90 % of plastic waste. In this article we present the results of research on novel starch-based compositions expected to be more safe for the marine environment. For these purpose biopolymers such as, thermoplastic starch (TPS), polylactide (PLA)...
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Collagen and hyaluronic acid hydrogel in water-in-oil microemulsion delivery systems
PublikacjaThe efficacy of microemul-sion in dermal and transdermal delivery of active ingredients. Here, we assessed the water-in-oilmicroemulsion capacity to incorporate two natural polymers, i.e. collagen and hyaluronic acid withlow and high molecular weight. Systems were extensively characterized in terms of conductivity, phaseinversion studies, droplet diameter, polydispersity index and rheological properties. The results of thisresearch...
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Performance properties of rigid polyurethane-polyisocyanurate/brewers’ spent grain foamed composites as function of isocyanate index
PublikacjaIn the presented work, rigid polyurethane-polyisocyanurate (PUR-PIR) foams filled with brewers’ spent grain (BSG) were prepared. The influence of the isocyanate index (II) on its performance was investigated. Foams obtained with higher isocyanate index required a higher amount of hydrofluorocarbon physical blowing agent to provide the same apparent density of material. An increase of isocyanate index resulted in a slight decrease...
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Structural changes of bacterial cellulose due to incubation in conditions simulating human plasma in the presence of selected pathogens
PublikacjaBacterial nanocellulose (BNC) is a natural biomaterial with a wide range of medical applications. However, it cannot be used as a biological implant of the circulatory system without checking whether it is biodegradable under human plasma conditions. This work aimed to investigate the BNC biodegradation by selected pathogens under conditions simulating human plasma. The BNC was incubated in simulated biological fluids with or...