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Search results for: Aromatic carboxylic acids
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Characterization of 1,3-alternate calix[4]arene-silica bonded stationary phases and their comparison to selected commercial columns by using principal component analysis
PublicationTwelve calix[4]arene stationary phases in 1,3-alternate conformation, synthesized in the authors laboratory, were characterized in terms of their surface coverage, hydrophobic selectivity, aromatic selectivity, shape selectivity, hydrogen bonding capacity and ion-exchange capacity. The set of tests commonly used for evaluation of commercially available stationary phases was applied to assess fundamental chromatographic properties...
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Bioactive polyurethanes applied as a surgical implants
PublicationSynthetic materials are applied in many branches of the industry, i.a. in medicine as a casing of apparatus, elements of artificial organs (hearts, blood vessels), catheters, wound healings, intra aortic balloons, mammary implants to mention but a few. Polymeric material used in such applications must be distinguished by a good biocompatybility. Since many years extensive research are employed to develop a new polymers that can...
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Influence of the boron doping level on the electrochemical oxidation of the azo dyes at Si/BDD thin film electrodes
PublicationIn this study the efficiency of electrochemical oxidation of aromatic pollutants, such as reactive dyes, at boron-doped diamond on silicon (Si/BDD) electrodes was investigated. The level of [B]/[C] ratio which is effective for the degradation and mineralization of selected aromatic pollutants, and the impact of [B]/[C] ratio on the crystalline structure, layer conductivity and relative sp3/sp2 coefficient of a BDD electrode were...
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Identification and characterization of the Indian Yellow dyestuff and its degradation products in historical oil paint tube by liquid chromatography mass spectrometry
PublicationAn analytical protocol for identification of dyes using reversed phase liquid chromatography-mass spectrometry with atmospheric pressure electrospray ionization (LC-ESI/MS) is presented. The developed method has been successfully applied in identification of euxanthic acid and euxanthone, the main components of the Indian Yellow dye in a historical oil paint tube produced by Richard Ain`es, a recognizable French company supplying...
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INFOGEST static in vitro simulation of gastrointestinal food digestion
PublicationDeveloping a mechanistic understanding of the impact of food structure and composition on human health has increasingly involved simulating digestion in the upper gastrointestinal tract. These simulations have used a wide range of different conditions that often have very little physiological relevance, and this impedes the meaningful comparison of results. The standardized protocol presented here is based on an international consensus...
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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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Fluorescence of p-hydroxyazobenzocrowns – Tautomeric equilibrium effect
PublicationThe spectroscopic properties of a series of para-hydroxyazobenzocrowns, including three novel compounds, were investigated using UV–Vis absorption and emission spectroscopy. This study presents, for the first time, determined quantum yield (QY) values for macrocycles of this category, ranging between 0.122 and 0.195. The highest values were obtained for crowns bearing two phenyl substituents in benzene rings. The impact of aromatic...
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The complete stereochemistry of the antibiotic candicidin A3 (syn. ascosin A3, levorin A3)
PublicationHerein, the stereostructure of the aromatic heptaene macrolide (AHM) antifungal antibiotic candicidin A3 (syn. ascosin A3, levorin A3) has been established upon the 2D NMR studies, consisting of DQF-COSY, TOCSY, ROESY, HSQC and HMBC experiments, as well as upon extensive molecular dynamics simulations. The geometry of the heptaenic chromophore was defined as: (22E, 24E, 26Z, 28Z, 30E, 32E, 34E). The previously unreported absolute...
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Selected organophosphorus compounds with biological activity. Applications in medicine
PublicationThe purpose of this article is to provide an overview of the latest applications of organophosphorus compounds (OPs) that exhibit biological activity. A large family of OPs have become popular in recent years. The practical application of OPs in modern medicine has been attributed to their unique properties. In this article, the methods used to select these compounds will be emphasized. This paper will first outline the findings...
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Rearrangement of azoxybenzocrowns into chromophoric hydroxyazobenzocrowns and the use of hydroxyazobenzocrowns for the synthesis of ionophoric biscrown compounds
PublicationThe Wallach rearrangement was used as a method for preparing p-hydroxyazobenzocrown ethers starting from different azoxybenzocrowns as substrates. Synthesis of a series of p-hydroxyazobenzocrowns under modified conditions and characterization of the obtained products are presented. o-Hydroxyazobenzocrowns were identified among the products of the photochemical rearrangement of azoxybenzocrowns. Novel biscrowns were synthesized...
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Hybrid battery based on arylated carbon nanotubes and laccase
PublicationSingle-walled carbon nanotubes (SWCNT) were covalently modified with anthracene and anthraquinone and used for the construction of cathodes for biocatalytic reduction of dioxygen. The nanotubes with aromatic groups casted onto the electrode increased the working surface of the electrode and enabled efficient direct electron transfer (DET) between the enzyme and the electrode. The aryl groups enter the hydrophobic pocket of the...
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Novel Diazocrowns with Pyrrole Residue as Lead(II) Colorimetric Probes
PublicationNovel 18- and 23-membered diazomacrocycles were obtained with satisfactory yields by diazocoupling of aromatic diamines with pyrrole in reactions carried under high dilution conditions. X-ray structure of macrocycle bearing five carbon atoms linkage was determined and described. Compounds were characterized as chromogenic heavy metal ions receptors. Selective color and spectral response for lead(II) was found in acetonitrile and...
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Immunosuppressive properties of amino acid and peptide derivatives of mycophenolic acid
PublicationMycophenolic acid (MPA) was coupled with amino acids and biologically active peptides including derivatives of tuftsin to modify its immunosuppressive properties. Both amino acid unit in the case of simple MPA amides and modifications within peptide moiety of MPA - tuftsin conjugates influenced the observed activity. Antiproliferative potential of the obtained conjugates was investigated in vitro and MPA amides with threonine methyl...
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Persistent organic pollutants (POPs) as an indicator of surface water quality in the vicinity of the Polish Polar Station, Horsund
PublicationSurface waters were collected in the vicinity of the Polish Polar Station in Hornsund (Svalbard) to determine their concentration of various persistent organic pollutants (POPs), such as polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). In addition, parameters such as pH, SEC and TOC were measured. In total, 15 samples of lake water from and 15 samples of stream water were analysed. The sampling took...
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Application of Diagnostic Ratios of PAHs to Characterize the Pollution Emission Sources
PublicationThe paper summarizes the potential of application of parent polycyclic aromatic hydrocarbons (PAHs) to identify their emission sources. Four parent PAHs diagnostic ratios are used for this purpose: anthracene/(anthracene + phenanthrene), fluoranthene/(fluoranthene + pyrene), benzo[a]pyrene/(benzo[a]pyrene + chryzene) and indeno[1,2,3-c,d]pyrene/(indeno[1,2,3-c,d]pyrene + benzo[g,h,i]perylene). The compounds of each ratio have the...
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Intermolecular Hydrogen Bonding Directed by Aryl–Perfluoroaryl π–π Stacking Interactions
PublicationThe crystal structures of five compounds capable of forming self-complementary hydrogen bonds but crystallizing as catemers or creating more complex crystal structures were compared with their complexes prepared by cocrystallization with perfluoroaryl compounds. The results of X-ray diffraction revealed that in all the cases the π–π stacking interactions caused reorganization of hydrogen bonds and induced creation of the expected...
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1,3,4-Thiadiazole-based diamides: Synthesis and complexation properties
PublicationAromatic diamides, derivative of 2,6-pyridinedicarboxylic acid and isophthalic acid, bearing 1,3,4-thiadiazole residue were prepared with satisfactory yields in conventional procedures and microwave stimulated reactions. X-ray structure of N,N-bis (1,3,4-thiadiazol-2-yl)-2,6-pyridinedicarboxamide (2) DMSO solvate (2DMSO) was described. Selective zinc(II), lanthanum(III), terbium(III) and L-tyrosine recognition was found for N,N-bis(1,3,4-thiadiazol-2-yl)-2,6-pyridinedicarboxamide...
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Silicon’s Influence on Polyphenol and Flavonoid Profiles in Pea (Pisum sativum L.) under Cadmium Exposure in Hydroponics: A Study of Metabolomics, Extraction Efficacy, and Antimicrobial Properties of Extracts
PublicationThe current study aimed to investigate the impact of silicon (Si) supplementation in the form of Na2SiO3 on the metabolome of peas under normal conditions and following exposure to cadmium (Cd) stress. Si is known for its ability to enhance stress tolerance in various plant species, including the mitigation of heavy metal toxicity. Cd, a significant contaminant, poses risks to...
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Nutraceutical value of persimmon (Diospyros kaki Thunb.) and its influence on some indices of atherosclerosis in an experiment on rats fed cholesterol-containing diet
PublicationThe nutraceutic value of persimmon (Diospyros kaki Thunb. cv. Triumph) and its influence on some indices of atherosclerosis were studied in vitro and in experiment on rats fed cholesterol-containing diet. It was found that persimmon possesses a high nutraceutical value: it contains soluble fibers, total polyphenols and phe - nolic acids. The content of dietary fiberwas 1.83 ± 0.11, 0.69 ± 0.07 and 1.14 ± 0.12 g/100 g fresh weight...
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Multidirectional Characterization of Phytochemical Profile and Health-Promoting Effects of Ziziphora bungeana Juz. Extracts
PublicationZiziphora species (Lamiaceae) have been used in traditional medicine as sedatives, anti-septics, carminatives, or expectorants. Despite their common applications in phytotherapy, there is still lack of evidence about the composition of their extracts and its impact on biological properties of the plants. The aim of this study was to evaluate the content of Ziziphora bungeana, a less studied species growing in Kazakhstan, using...
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Novel Functionalization of Boron-Doped Diamond by Microwave Pulsed-Plasma Polymerized Allylamine Film
PublicationWe report the novel modification of a hydrogen-terminated polycrystalline boron-doped electrode with a microwave pulsed-plasma polymerized allylamine. Boron-doped diamond (BDD) was coated with a very thin layer of adherent cross-linked, pinhole- and additive-free allylamine plasma polymer (PPAAm) resistant to hydrolysis and delamination and characterized by a high density of positively charged amino groups. The pulsed microwave...
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Stopniowa chromatografia cienkowarstwowa w normalnych układach faz (NP-TLC), jako technika rozdzielania i oceny składu grupowego frakcji asfaltenowych z utleniania pozostałości próżniowej ropy naftowej
PublicationW pracy opisano wyniki badań nad opracowaniem metodyki oceny składu grupowego i czystości frakcji asfaltenowych techniką chromatografii cienkowarstwowej w normalnych układach faz (NP-TLC). Skupiono się na doborze takich parametrów/warunków rozdzielania, jak stężenie i masa próbki, a także skład i kolejność eluentów stosowanych podczas rozwijania chromatogramów TLC. Zastosowana trój-stopniowa metodyka polega na nałożeniu 5 µL frakcji...
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Waterborne polyesters partially based on renewable resources
PublicationA new experimental approach for preparing biobased, water-soluble polyesters via titanium(IV) n-butoxide-catalyzed bulk polycondensation is presented. In the described method polymers were obtained from isosorbide, maleic anhydride and poly(ethylene glycol). The chemical structure of the synthesized polyesters was confirmed using 2D NMR spectroscopy and by titration methods. Careful analysis of 2D NMR spectra viz. Correlation Spectra...
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Molecular Umbrellas Modulate the Selective Toxicity of Polyene Macrolide Antifungals
PublicationAntifungal polyene macrolide antibiotics Amphotericin B (AmB) and Nystatin (NYS) were conjugated through the ω-amino acid linkers with diwalled “molecular umbrellas” composed of spermidine-linked deoxycholic or cholic acids. The presence of “umbrella” substituents modulated biological properties of the antibiotics, especially their selective toxicity. Some of the AmB-umbrella conjugates demonstrated antifungal in vitro activity...
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Bioactive Ingredients with Health-Promoting Properties of Strawberry Fruit (Fragaria x ananassa Duchesne)
PublicationStrawberries (Fragaria x ananassa Duchesne) belong to the berry group and are characterized primarily by delightful sensory properties. Due to their chemical composition, these fruits are a rich source of bioactive compounds that can modify the metabolic and physiological functions of the body. The aim of this work is to present the current state of research on bioactive ingredients found in these fruits in the context of their...
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Amino Acid Based Antimicrobial Agents – Synthesis and Properties
PublicationStructures of several dozen of known antibacterial, antifungal or antiprotozoal agents are based on the amino acid scaffold. In most of them, the amino acid skeleton is of a crucial importance for their antimicrobial activity, since very often they are structural analogs of amino acid intermediates of different microbial biosynthetic pathways. Particularly, some aminophosphonate or aminoboronate analogs of protein amino acids are...
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Purification of model biogas from toluene using deep eutectic solvents
PublicationBiogas from landfills and wastewater treatment facilities typically contain a wide range of volatile organic compounds (VOCs), that can cause severe operational problems when biogas is used as fuel. Among the contaminants commonly occur aromatic compounds, i.e. benzene, ethylbenzene, toluene and xylenes (BTEX). In order to remove BTEX from biogas, different processes can be used. A promising process for VOCs removal is their absorption...
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Environmental risk- based ranking of solvents by the combination of multimedia model and multi-criteria decision analysis
PublicationA novel procedure for assessing the environmental risk related to solvents emissions has been developed. The assessment of risk is based on hazard and exposure detailed investigations. The potential exposure related to different environmental phases is calculated with basic multimedia model, that gives the percentage distribution of solvent in environmental compartments as a result. Specific hazards– toxicological, environmental...
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Chromogenic amides of pyridine-2,6-dicarboxylic acid as anion receptors
PublicationThe synthesis of simple, chromogenic pyridine-2,6-dicarboxylic acid amides, derivates of isomeric nitroanilines and aminonitrophenols, and their ion binding properties are described. The ligands' response to ionic species was examined by naked eye and was studied with the use of UV-Vis spectroscopy in DMSO and its mixture with water. The effect of the localisation and the type of the substituents in aromatic rings were discussed....
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Contaminants in airport runoff water
PublicationDespite the many positives ensuing from the rapid expansion of the air transport sector, airport operations as a whole are a substantial source of environmental pollution.Increases in aviation developments have serious consequences on the surrounding air, soil and water bodies like lakes, rivers and ground water. The present work deals with the determination of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls...
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Topochemical, Single‐Crystal‐to‐Single‐Crystal [2+2] Photocycloadditions Driven by Chalcogen‐Bonding Interactions
PublicationThe face-to-face association of (E)-1,2-di(4-pyridyl)ethylene (bpen) molecules into rectangular motifs stabilized for the first time by chalcogen bonding (ChB) interactions is shown to provide photoreactive systems leading to cyclobutane formation through single-crystal-to-single-crystal [2+2] photodimerizations. The chelating chalcogen bond donors are based on original aromatic, ortho-substituted bis(selenocyanato)benzene derivatives...
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The Quaternization Reaction of 5-O-Sulfonates of Methyl 2,3-o-Isopropylidene-β-D-Ribofuranoside with Selected Heterocyclic and Aliphatic Amines
PublicationThe synthesis of N-((methyl 5-deoxy-2,3-O-isopropylidene-β-D-ribofuranoside)-5-yl) ammonium salts are presented. To determine the effect of the nucleophile type and outgoing group on the quaternization reaction, selected aliphatic and heterocyclic aromatic amines reacted with: methyl 2,3-O-isopropylidene-5-O-tosyl-β-D-ribofuranoside or methyl 2,3-O-isopropylidene-5-O-mesyl-β-D -ribofuranoside or methyl 2,3-O-isopropylidene-5-O-triflyl-β-D-ribofuranoside...
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Monetary values estimates of solvents emissions
PublicationThe impact values for environmental emissions of 52 solvents are estimated and expressed in monetary units. The impact values of solvents present in the air are calculated on the basis of 13 impact indicators and for solvents present in water on additional 2 impact indicators. These impact values are weighted with the results obtained with multi-compartment distribution model, allowing to calculate the fraction of solvent emitted...
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Phenolic Content and Related Antioxidant Activities in in vitro Cultures of Cephalotaxus Harringtonia L. Grown in Egypt
PublicationAbstract: Quantitative estimation of the total phenolics, total flavonoids, antioxidant activity and HPLC analysis of phenolic compounds in the mother plant, in vitro shooting and callus cultures of Cephalotaxus harringtonia L. grown in Egypt were measured. For shooting behaviour, using Woody plant medium (WPM) with 2 mg/l Benzyladinin (BA) in the second subculture gave the highest number of shootlet/explant (2.33 shootlet/explant)...
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The content of conjugated linoleic acid and vaccenic acid in the breast milk of women from Gdansk and the surrounding district, as well as in, infant formulas and follow-up formulas. Nutritional recommendation for nursing women
PublicationFatty acids are some of the most important components of human milk. Polyunsaturated fatty acids (PUFAs) are essential nutrients required for the optimal growth and development of infants, especially the central nervous system, brain and retina. AIM: To determine the conjugated linolenic acid (CLA) and vaccenic acid (VA) content of human breast milk from mothers consuming different diets, and to compare the results with CLA and...
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Natural fish oil improves the differentiation and maturation of oligodendrocyte precursor cells to oligodendrocytes in vitro after interaction with the blood–brain barrier
PublicationThe blood–brain barrier (BBB) tightly controls the microenvironment of the central nervous system (CNS) to allow neurons to function properly. Additionally, emerging studies point to the beneficial effect of natural oils affecting a wide variety of physiological and pathological processes in the human body. In this study, using an in vitro model of the BBB, we tested the influence of natural fish oil mixture (FOM) vs. borage oil...
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Effect of microwave and convection heating on selected nutrients of human milk
PublicationThe aim of this study was to determine the influence of the microwave heating method (MWH) on selected determinants of the nutritional value of human milk (HM) and compare to the effect exerted by the standard convection heating (CH) method, including holder pasteurization (HoP). It was showed that using MWH under conditions assumed to ensure microbiological safety, changes in the level of the nutrients were not observed. In these...
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Novel Research on Biomedical Polyurethanes
PublicationThe variety of mechanical properties characterizes properly designed PURs. They may be biocompatible and reveal compatibility with blood, making them attractive materials for the fabrication of tissue scaffolds; however, like all synthetic materials, PURs don’t reveal sufficient biocompatibility. PURs may undergo certain chemical modifications (e.g., 1,4:3,6-dianhydro-D-sorbitol, ascorbic acid (AA), growth factors, covering with...
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An unusual four-nuclear Pb(II)-pyrrole-2-carboxylato polymer: The effect of the lone pair and non-covalent interactions on the supramolecular assembly and fluorescence properties
PublicationThe reaction of Pb(NO3)2 with 1H-pyrrole-2-carboxylic acid (2prCOOH) leads to the formation of a new four-nuclear Pb(II) polymer, [Pb4(2prCOO)8(H2O)]n, which has been characterized by CHN, FT-IR, TG, PL and single-crystal X-ray diffraction methods. In view of the primary Pb–O bonds, Pb1 and Pb3 show hemidirected pentagonal pyramidal geometries, while Pb2 and Pb4 display hemidirected octahedral geometries. The topology of the strongest...
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A new tool for the evaluation of the analytical procedure: Green Analytical Procedure Index
PublicationA new means for assessing analytical protocols relating to green analytical chemistry attributes has been developed. The new tool, called GAPI (Green Analytical Procedure Index), evaluates the green character of an entire analytical methodology, from sample collection to final determination, and was created using such tools as the National Environmental Methods Index (NEMI) or Analytical Eco-Scale to provide not only general but...
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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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Origin of bitumen fractions in the Jurassic-early Cretaceous Vaca Muerta Formation in Argentina: insights from organic petrography and geochemical techniques
PublicationThis paper investigates chemical functional groups of the two extracted bitumen fractions in shales of the Jurassic to early Cretaceous Vaca Muerta Formation of the Neuquén Basin in Argentina, South America. The results indicate that Bitumen I is strongly aliphatic and appears to be genetically related to fluorescent amorphous organic matter. In contrast, Bitumen II consists of highly condensed, aromatic hydrocarbons, and has some...
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Solid phase microextraction–comprehensive twodimensional gas chromatography–time-of-flight mass spectrometry: a new tool for determining PAHs in airport runoff water samples
Publicationfundamental aspect of airport operations is the pollution caused by airport runoff waters. Polycyclic aromatic hydrocarbons (PAHs) are one of the most important groups of xenobiotics which are commonly found in runoff water originating from airports. Only very limited data on the analysis of airport runoff water have been published until now. Therefore, a reliable and accurate analytical method based on headspace solid-phase microextraction...
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Contamination of Arctic Lakes with Persistent Toxic PAH Substances in the NW Part of Wedel Jarlsberg Land (Bellsund, Svalbard)
PublicationThe expansion of glacier‐free areas in polar regions favours the appearance of lakes in the non‐glaciated parts of glacier basins. This paper presents the differentiation of organic compound concentrations in fifty‐four Arctic lakes collected in four locations (Logne Valley, in the vicinity of the Scott, Renard and Antonia glaciers). We cover meteorological measurements, chemical analysis of sixteen dioxin‐like compounds (Polycyclic...
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Voriconazole-Based Salts Are Active against Multidrug-Resistant Human Pathogenic Yeasts
PublicationVoriconazole (VOR) hydrochloride is unequivocally converted into VOR lactates and valinates upon reaction with silver salts of organic acids. This study found that the anticandidal in vitro activity of these compounds was comparable or slightly better than that of VOR. The Candida albicans clinical isolate overexpressing CaCDR1/CaCDR2 genes, highly resistant to VOR, was apparently more susceptible to VOR salts. On the other hand,...
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Investigation on domestic fruits seed oils in personal care emulsion systems
PublicationThe use of fruit seed oils in personal care products is of significance to both their function and image. Poland is an important processor of fruit products within the EU, and thus has a large availability of seeds from domestic fruits, which are normally considered to be a waste material. Unfortunately, current literature is scarce of the suitability of these oils for topical use in the form of cosmetic emulsions. Published data...
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Sewage sludge pretreatment by low thermal disintegration for better efficacy of sludge digestion process
PublicationThe wastewater water treatment plant (WWTP) sector and it is developing technologies strive to be implement circular economy. The methane production from the sludge digestion process constitute promising source of the renewable energy for WWTP and approaching circular economy assumptions. For this reason, the objective of the study was to examine the modification of sludge characteristics due to the low temperature pretreatment....
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Literature update of analytical methods for biogenic amines determination in food and beverages
PublicationBiogenic amines (BAs) have been reported in a variety of foods, such as fish, meat, cheese, and wines. The formation of BAs in food by the microbial decarboxylation of amino acids can result in human allergic reactions, characterized by difficulty in breathing, rash, vomiting, and hypertension. Control measures to prevent biogenic amine formation in foods and/or reduce their levels should be considered. Therefore, monitoring of...
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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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Aminy w środowisku - niebezpieczeństwo czy jego naturalny element?
PublicationA lot of amines and their compounds are used in the industry. First of all they are used for the preparation of medicines, plant protection agents, fertilizers and plastics. Amines are also released into the environment as a result of natural biological processes such as the release of certain species of flowers to lure insects, and also biochemical breakdown of amino acids in the protein during decomposition of organic matter. Unfortunately,...