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Structure-rheology relationship of fully bio-based linear polyester polyols for polyurethanes - Synthesis and investigation
PublicationThe synthesis of polyols from renewable substances as an alternative for petrochemical-based polyols play important matter in the polyurethane industry. In this work, the fully bio-based linear polyester polyols with different catalyst amounts were synthesized via two-step polycondensation method. The effect of various catalyst content on the structure and rheological behavior were established. Fourier Transform Infrared Spectroscopy,...
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Rheology of liquid crystalline polymers
PublicationLiquid crystallinity was invented in the 19th century. It was sometimes called the fourth state of matter because of the ability of macromolecules to generate liquid crystal phases. The main classification divided liquid crystalline polymers (LCPs) into lyotropic and thermotropic types. Interpretation of the rheological behavior of LCP is more complicated than for other polymers. Ordinary polymers are characterized by a normal...
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Direct human contact with siloxanes (silicones): safety or risk. Part 1: characteristics of siloxanes (silicones
PublicationSiloxanes are commonly known as silicones. They belong to the organosiliconcompounds and are exclusively obtained by synthesis. Their chemical structuredetermines a range of physicochemical properties which were recognized as unique.Due to the susceptibility to chemical modifications, ability to create short, long orcomplex polymer particles, siloxanes found an application in many areas of human life.
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The use of chain extenders as processing aids in the valorization of single-use polylactide (PLA) products by rotomolding
PublicationBiodegradable plastics in single-use products have increased in popularity as a way to reduce the negative environmental impact of conventional plastics and meet the tightening law regulations. However, their recyclability needs to be assessed, as the environmental behavior of single-use plastics, even if compostable, is not negligible. Polylactide (PLA) is susceptible to thermal, oxidative, hydrolytic, and mechanical degradation...
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Effect of hydroxylated soybean oil and bio-based propanediol on the structure and thermal properties of synthesized bio-polyurethanes
PublicationThe aim of this work was to obtain bio-polyurethanes using synthetic compounds and bio-components, i.e. bio-glycols. Bio-polyurethanes were prepared by means of the prepolymer method. Prepolymers were synthesized from 4,4′-diphenylmethane diisocyanate (MDI) and a polyol mixture containing 75% by weight of commercial polyether and 25% by weight of hydroxylated soybean oils (H2 or H3), the latter being obtained in the reaction with...
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Rhodotorulic Acid and its Derivatives: Synthesis, Properties, and Applications
PublicationSiderophores are low molecular weight compounds produced by microorganisms to scavenge iron in iron-deficient environments. Rhodotorulic acid (RA), a natural hydroxamate siderophore, plays a vital role in iron acquisition for fungi and bacteria. As the simplest natural hydroxamate siderophore, RA exhibits a high affinity for ferric ions, enabling it to form stable complexes that facilitate iron uptake and transport within microorganisms....
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Właściwości mechaniczne tworzywa PET - przegląd literatury
PublicationThe article describes the influance of the microstructure and environment conditions on the mechanical properties of PET material. From the microskopic point of view, mechanical and thermal properties of PET material have the biggest influance on orientation and crystallization processes of material. From the macroskopic point of view mechanical properties can be described by parameters derived from strees-strain mechanical answers...
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OBTAINING OF COUMARONE-INDENE RESINS BASED ON LIGHT FRACTION OF COAL TAR 3. COUMARONE-INDENE RESINS WITH METHACRYLIC FRAGMENTS
PublicationThe method for obtaining coumarone-indene resins with methacrylic fragments (CIRM) was developed with the addition of methyl ethacrylate, using a light fraction of coal tar and its fraction boiling within 423–463 К. CIRM was obtained via radical cooligomerization using 2,2'-azobis (2-methyl-propionitrile) as the initiator. The effect of the initiator amount, temperature and reaction time on the yield, softening temperature and...
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Synthesis and characterization of novel renewable polyesters based on 2,5-furandicarboxylic acid and 2,3-butanediol
PublicationNovel polyesters from 2,5-furandicarboxylic acid or 2,5-dimethyl-furandicarboxylate and 2,3-butanediol have been synthesized via bulk polycondensation catalyzed by titanium (IV) n-butoxide, tin (IV) ethylhexanoate, or zirconium (IV) butoxide. The polymers were analyzed by size exclusion chromatography, nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy (FTIR), matrix-assisted laser ionization-desorption...
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Waldenstrom macroglobulinemia - Female, 50 - Tissue image [3300730069453581]
Open Research DataThis is the histopathological image of HEMATOPOIETIC AND RETICULOENDOTHELIAL SYSTEMS tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Waldenstrom macroglobulinemia - Female, 50 - Tissue image [11290630017293601]
Open Research DataThis is the histopathological image of HEMATOPOIETIC AND RETICULOENDOTHELIAL SYSTEMS tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Waldenstrom macroglobulinemia - Female, 50 - Tissue image [3300730069459481]
Open Research DataThis is the histopathological image of HEMATOPOIETIC AND RETICULOENDOTHELIAL SYSTEMS tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Renewable natural resources as green alternative substrates to obtain bio-based non-isocyanate polyurethanes-review
PublicationCommercially available polyurethanes are synthesized by the polyaddition of diisocyanates with polyols and low molecular weight chain extenders. A new approach to polyurethanes synthesis is realized via non-isocyanate routes. Negative impacts of petroleum-based chemicals on the environment and human health as well as gradual reduction of fuel-based resources, which leads to an increase in their prices, are an incentive to looking...
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The structure of novel polyurethanes containing synthetic poly[(R,S)-3-hydroxybutyrate]
PublicationThe aim of this study was to estimate the structure of new polyurethanes with the potential to be used in medicine. Atactic poly[(R,S)-3-hydroxybutyrate], obtained via a ring-opening polymerization, and polycaprolactonediol or polyoxytetramethylenediol were used to built the soft segments. 4,4'-methylene dicyclohexyl diisocyanate and 1,4-butanediol were the components to form hard segments. Polyurethanes with low-molecular weight...
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How Chain Transfer Leads to a Uniform Polymer Particle Morphology and Prevents Reactor Fouling
PublicationABSTRACT: The effect of adding diethyl zinc as a chain transfer agent during the polymerization of propylene in heptane performed at 80 °C was studied. Although it was expected that the chain transfer would stop after precipitation of the polymer, the polymer molecular weight continued to increase throughout the whole of the polymerization. The presence of diethyl zinc had an additional effect that the polymerizations were devoid...
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Novel, Fully Biobased Semicrystalline Polyamides
PublicationNovel, semicrystalline polyamides and co(polyamides) were synthesized from biobased sebacic acid (SA), 2,5-diamino-2,5-dideoxy-1,4;3,6-dianhydroiditol (diaminoisoidide, DAII) as well as from 1,4-diaminobutane (DAB), also known as putrescine in nature. Low molecular weight polyamides were obtained by melt polycondensation of the salts based on these monomers or by interfacial polycondensation. In order to increase their molecular...
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Waldenstrom macroglobulinemia - Female, 50 - Tissue image [11290630017292111]
Open Research DataThis is the histopathological image of HEMATOPOIETIC AND RETICULOENDOTHELIAL SYSTEMS tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Waldenstrom macroglobulinemia - Female, 50 - Tissue image [3300730069457891]
Open Research DataThis is the histopathological image of HEMATOPOIETIC AND RETICULOENDOTHELIAL SYSTEMS tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Waldenstrom macroglobulinemia - Female, 50 - Tissue image [11290630017294351]
Open Research DataThis is the histopathological image of HEMATOPOIETIC AND RETICULOENDOTHELIAL SYSTEMS tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Waldenstrom macroglobulinemia - Female, 50 - Tissue image [11290630017296721]
Open Research DataThis is the histopathological image of HEMATOPOIETIC AND RETICULOENDOTHELIAL SYSTEMS tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Waldenstrom macroglobulinemia - Female, 50 - Tissue image [11290630017291451]
Open Research DataThis is the histopathological image of HEMATOPOIETIC AND RETICULOENDOTHELIAL SYSTEMS tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Waldenstrom macroglobulinemia - Female, 50 - Tissue image [11290630017294051]
Open Research DataThis is the histopathological image of HEMATOPOIETIC AND RETICULOENDOTHELIAL SYSTEMS tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Waldenstrom macroglobulinemia - Female, 50 - Tissue image [11290630017297561]
Open Research DataThis is the histopathological image of HEMATOPOIETIC AND RETICULOENDOTHELIAL SYSTEMS tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Waldenstrom macroglobulinemia - Female, 50 - Tissue image [11290630017293021]
Open Research DataThis is the histopathological image of HEMATOPOIETIC AND RETICULOENDOTHELIAL SYSTEMS tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Analysis of the Possibility of Using New Types of Protective Coatings and Abrasion-Resistant Linings under the Operating Conditions of the Spiral Classifier at KGHM Polska Miedź S.A. Ore Concentration Plant
PublicationA study was carried out to select the appropriate coatings for corrosion protection of the spiral classifier working at KGHM Polska Miedź S.A. Ore Concentration Plant. The abrasion resistance of selected protective coatings and wear-resistant linings was investigated using a DT-523 rotary abrasion tester with Taber CS-10 rubber abrasive discs. The average weight loss of the coatings after a cycle of 2000 revolutions was determined....
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Novel Biomass-Based Polymers: Synthesis, Characterization, and Application
PublicationA wide range of polymers were prepared from biomass-derivatives, using different polymerization mechanisms. Well-defined, fully hydroxy-functional polyesters based on aliphatic diols were synthesized, using either conventional metal-based catalysts or the organic superbase 1,5,7-triazabicyclododecene (TBD). Unsaturated polyesters were also made, offering additional functionality to these biobased resins. Metal-catalyzed or enzymatic...
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Nonconventional 1,8-Diazafluoren-9-One Aggregates for Green Light Enhancement in Hybrid Biocompatible Media
PublicationOrganic aggregates currently play a prominent role, mainly for their unique optoelectronic properties in the aggregated state. Such properties can be related to the aggregates’ structure and the molecular packing mode. In the literature, we have well-established models of H and J aggregates defined based on the molecular exciton model. However, unconventional aggregates, the most unrecognized forms, have been generating interest...
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Rheology of potato starch chemically modified with microwave-assisted reactions
PublicationNative potato starch was sulfated, selenated, borated, silicated and zincatated by means of microwave-assisted reactions with varying doses of relevant reagents. Resulting products were characterized involving rheological behavior of pastes, their weight-average molecular weight (Mw), and radius of gyration (Rg). Most of the pastes showed shear-thinning behavior, with the flow behavior index (n) below unity. The pastes of starch...
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Structure-property relationships in peroxide-assisted blends of poly(ε-caprolactone) and poly(3-hydroxybutyrate)
PublicationPoly(ε-caprolactone) and poly(3-hydroxybutyrate) (PCL/PHB) blends in two weight ratios (75/25 and 50/50) were reactively compatibilized in the presence of di-(2-tert-butyl-peroxyisopropyl)-benzene and dicumyl peroxide as free radical initiators. Rheological, mechanical, thermal properties and morphological features, as well as the chemical structure of PCL/PHB blends were investigated. It was found that regardless of PCL/PHB blend...
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Inhibition of amyloid fibril formation of hen egg white lysozyme by trimethylamine N-oxide at low pH
PublicationIn vitro inhibition of the formation of fibrous aggregates of proteins (amyloids) has gained increasing attention due to the number of diseases associated with protein misfolding and fibrillation. An interesting group of compounds for which pronounced activity against this phenomenon can be expected consists of low molecular weight substances (osmolytes) which have the ability to change protein stability. Here we investigate the...
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Identification and cloning of C. albicans SC5314 genes encoding L-methionine biosynthetic pathway enzymes.
Open Research DataEnzymes of fungal L-methionine biosynthetic pathway: homoserine O-acetyltransferase (Met2p), O-acetylhomoserine sulfhydrylase (Met15p) and cystathionine-γ-synthase (Str2p) could be exploited as molecular targets for antifungal chemotherapy. The goal of the study was to identify and clone genes encoding mentioned above enzymes. MET2, MET15 and STR2 genes...
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A highly thermostable, homodimeric single-stranded DNA-binding protein from Deinococcus radiopugnans
PublicationWe report the identification and characterization of the single-stranded DNA-binding protein (SSB) from the mesophile and highly radiation-resistant Deinococcus radiopugnans (DrpSSB). PCR-derived DNA fragment containing the complete structural gene for DrpSSB protein was cloned and expressed in Escherichia coli. The gene consisting of an open reading frame of 900 nucleotides encodes a protein of 300 amino acids with a calculated...
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ABSORPCJA, METABOLIZM I ROLA BIOLOGICZNA KWASÓW NUKLEINOWYCH OBECNYCH W ŻYWNOŚCI
PublicationKwasy nukleinowe należą do niedocenianych składników żywności, szczególnie surowej lub nisko przetworzonej. W niniejszej publikacji skupiono się na omówieniu przemian, jakim podlegają kwasy nukleinowe w przewodzie pokarmowym człowieka, procesie absorpcji nukleotydów oraz nukleozydów z przewodu pokarmowego, a także przedstawiono podstawowe etapy ich metabolizmu w komórkach organizmu. Produkty trawienia kwasów nukleinowych stanowią...
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Microwave radiation in the synthesis of urethane prepolymers
PublicationThis paper describes the use of microwave radiation in the synthesis of urethane prepolymers in bulk (without solvent). The prepolymers were synthesized using 1,6-hexamethylene diisocyanate (HDI) and poly (ε-caprolactone) diol (PCL) at a molar ratio of 4:1. The reaction was carried out without a catalyst in the reactor with a conventional heating system (oil bath) or in the microwave reactor (MW Reactor NOVA 09) at temperatures...
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Thermoplastic polyurethanes derived from petrochemical or renewable resources: A comprehensive review
PublicationThermoplastic polyurethanes (TPUs) materials are obtained by the reaction of polyol (ether-, ester-, and carbonate-based diols with average molecular weight in the range from 1,000 to 3,000 g/mol) with aliphatic or aromatic diisocyanates. Synthesized materials consist of the hard and soft segments which are separated in different level. All mechanical and thermal properties of TPUs depend on the chemical structure of used monomers,...
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The Influence of the Co-Dopant Dexamethasone Phosphate on the Electrodeposition Process and Drug-Release Properties of Polypyrrole-Salicylate on Iron
PublicationIn this work, the influence of incorporation of two anti-inflammatory drugs dexamethasone phosphate and sodium salicylate on the electrodeposition process of polypyrrole (PPy) film on iron has been studied. The incorporation of the agents into PPy has been carried out in a one-step electropolymerization process on oxidizable iron. The role of each drug agent during the deposition process has been discussed. The morphological and...
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Chitin and derivative chitosan-based structures — Preparation strategies aided by deep eutectic solvents: A review
PublicationThe high molecular weight of chitin, as a biopolymer, challenges its extraction due to its insolubility in the solvents. Also, chitosan, as the N-deacetylated form of chitin, can be employed as a primary material for different industries. The low mechanical stability and poor plasticity of chitosan films, as a result of incompatible interaction between chitosan and the used solvent, have limited its industrialization. Deep eutectic...
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Waldenstrom macroglobulinemia - Female, 50 - Tissue image [11290630017299501]
Open Research DataThis is the histopathological image of HEMATOPOIETIC AND RETICULOENDOTHELIAL SYSTEMS tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Examination of fresh water chemistry in maritime Antarctica during austral summer 2017
PublicationDue to the fact that Antarctica is one of the least polluted places on Earth, it is a perfect place to observe the spread of global pollution. Therefore, research conducted on this continent is important due to the possibility of investigating the type of pollution and their way of transport. This work considers presence of organic contaminants in Maritime Antarctica in unexplored until now, Lions Rump headland. Qualitative and...
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LC-MS and LC-NMR as Complementary Techniques for the Determination of Pharmaceuticals in Dosage Formulations
PublicationPharmaceuticals contain not only pharmacologically active compounds but also a range of excipients. The danger exists that impurities may also be present in such drugs, which may adversely affect their efficacy and even endanger patient health and life. Monitoring the composition of pharmaceutical products is therefore essential. The trace amounts of such impurities in pharmaceuticals are often identified and determined with liquid...
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Studies on applicability of new solid-phase microextraction fibers for the selective extraction and determination of short - chain monocarboksylic acids
PublicationShort-chain monocarobxylic acids, sometimes referred to as volatile fatty acids (VFA), are a group of low molecular weight alkyl monocarboxylic acids that are widely distributed within the environment. These molecules contain any from 2 to 8 carbon atoms and originate from the anaerobic biodegradation of organic matter such as carbohydrates, proteins, and fats. These compounds are commonly found in the effluents from animal farming,...
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The effect of polyamide PA12 and polyester PBT blocks' lengths on the structure and propertries of multiblock terpoly(amide-block-ester-block-amide) (TPAEA)
PublicationThe ternary multiblock system terpoly(amide-b-ester-b-amide) (TPAEA) of the chemical structure: poly[(oligoamide-6.36)-block-(tetramethylene terephthalate)-block-laurolactam)] -(PA6.36-b-PBT-b-PA12)n- has been obtained (Table 1). In this system the third component (PBT block here), characterized with the proper molecular weight, is dissolved in hard phase of PA12 blocks and partially dissolved in soft phase of PA6.36. The effects...
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Vegetable derived-oil facilitating carbon black migration from waste tire rubbers and its reinforcement effect
PublicationThree dimensional chemically cross-linked polymer networks present a great challenge for recycling and reutilization of waste tire rubber. In this work, the covalently cross-linked networks of ground tire rubber (GTR) were degraded heterogeneously under 150 °C due to the synergistic effects of the soybean oil and controlled oxidation. The degradation mechanism was discussed using Horikx theory and Fourier transformation infrared...
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Recycling of Polyurethanes Containing Flame-Retardants and Polymer Waste Transformed into Flame-Retarded Polyurethanes
PublicationThe growing number of polyurethanes (PUs) produced every year has developed methods for their mechanical and chemical recycling which yield valuable products like substitutes for commercial polyols or flame-retardants. PUs can be produced in different shapes and forms (i.e., elastomers, flexible or rigid foams, coatings, etc.) using several different components (i.e., di- or polyisocyanates, ester- or ether-based polyols, low-molecular...
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Waldenstrom macroglobulinemia - Female, 50 - Tissue image [11290630017291461]
Open Research DataThis is the histopathological image of HEMATOPOIETIC AND RETICULOENDOTHELIAL SYSTEMS tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Waldenstrom macroglobulinemia - Female, 50 - Tissue image [11290630017282841]
Open Research DataThis is the histopathological image of HEMATOPOIETIC AND RETICULOENDOTHELIAL SYSTEMS tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
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Problems with modelling the strength properties of sailing vessels rigging ropes
PublicationThis article presents the basic parameters of soft ropes: natural fibre ropes, soft wire ropes and synthetic fibre ropes used for running rigging. There are only several materials still used for the production of natural fibre ropes, including cotton, jute, hemp, sisal and manila hemp. The most commonly used soft wire ropes are twisted pair ropes; for smaller diameters there is a 6x19M - FC rope and for larger diameters – 6x37M...
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Effect of modified soybeen oil amount on rheological characteriza-tion of polyurethane pre-polymers
PublicationPolyurethanes (Pu’s) are the polymeric materials which have got urethane groups in the structure. The properties of Pu’s depend both on the method of preparation and monomers used. Polyurethanes are produced by two methods known as one step or two step method called as “pre-polymers method”, especially for the case of segmented polyurethanes (SPU’s). These materials are thermoplastic block copolymers of the (AB)n type consisting...
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Copolymerization of Styrene and Pentadecylphenylmethacrylate (PDPMA): Synthesis, Characterization, Thermomechanical and Adhesion Properties
PublicationThe copolymerization of styrene (St) with a bioderived monomer, pentadecylphenylmethacrylate (PDPMA), via atom transfer radical polymerization (ATRP) was studied in this work.The copolymerization reactivity ratio was calculated using the composition data obtained from1HNMR spectroscopy, applying Kelen-Tudos and Finemann-Ross methods. The reactivity ratio of styrene (r1=0.93) and PDPMA (r2=0.05) suggested random copolymerization...
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Unsaturated, biobased polyesters and their cross-linking via radical copolymerization
PublicationBiobased, unsaturated polyesters derived from isosorbide, maleic anhydride and succinic acid were synthesized and characterized. The presence of maleic anhydride units in the structure of the polyesters allowed converting them into cured coatings by radical copolymerization with cross-linking agents such as 2-hydroxyethyl methacrylate, N-vinyl-2-pyrrolidinone, acrylic acid or methacrylamide. The investigated polyesters were obtained...