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Photoelectron spectroscopy of a series of acetate and propionate esters
PublikacjaThe electronic state and photoionization spectroscopy of a series of acetate esters: methyl acetate, isopropyl acetate, butyl acetate and pentyl acetate as well as two propionates: methyl propionate and ethyl propionate, have been determined using vacuum-ultraviolet photoelectron spectroscopy. These experimental investigations are complemented by ab initio calculations. The measured first adiabatic and vertical ionization energies...
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Biodegradability of modified emulsifiers - esters of polyols and fatty acids
PublikacjaBadano podatność na biodegradację wybranych emulgatorów estrów polioli i kwasów tłuszczowych przy użyciu testu zamkniętej butelki (OECD 301 D). Stwierdzono, że badane emulgatory nie mogą zostać uznane za łatwo ulegające biodegradacji. Najwyższy poziom rozkładu (57,3%) osiągnął emulgator C14Gna, najniższy (29,8%) AEGNa.
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Sweet surfactants I: Fatty acid esters of sucralose
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Atom-economic thiophosphoroselenenylations of C–H acid esters and amides
PublikacjaThree improved thiophosphoroselenenylation procedures of CHacids, including derivatives of malonic and acetyl-, phosphono-, 4-nitrophenyl- and 3-pyridylacetic acids, have been described and compared to previously reported thiophosphoroselenylation of diethyl malonate using bis(disopropoxyphosphinothioyl)diselenide alone or with the aid of methyl iodide. The use of iodine makes it possible to utilize both equivalents of the selenenylating...
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Synthesis of polyglycerol esters of fatty acid with defined hydrophilic properties
PublikacjaOtrzymane w odrębnej reakcji mieszaniny poligliceroli poddano estryfikacji kwasami tłuszczowymi oktadekanowym i izooktadekanowym, w obecności odpowiednich mydeł sodu powstających in situ. Zaobserwowano wpływ stężenia karboksylanów sodu oraz budowy kwasu tłuszczowego na przebieg estryfikacji mieszaniny polioli. Stwierdzono, że zastosowany sposób prowadzenia reakcji pozwala zsyntetyzować efektywne emulgatory emulsji O/W, o wartościach...
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Polyglycerol esters of lauric acid with defined hydrophile-lipophile properties.
PublikacjaZsyntetyzowano estrowe pochodne poligliceroli i kwasu laurynowego w obecności laurynianu sodu powstającego in situ. Przeanalizowano wpływ temperatury, stężenia katalizatora oraz czasu reakcji na postęp reakcji polimeryzacji glicerolu, a także wpływ stężenia karboksylanu i czasu reakcji na reakcję estryfikacji uzyskanej mieszaniny polioli kwasem laurynowym. Zauważono, że zastosowana metoda syntezy estrów poligliceroli prowadzi do...
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Molecular self-assembly and optical activity of chiral thionooxalamic acid esters
PublikacjaZsyntezowano kilka optycznie czynnych estrów dietylowych kwasu bis(tiooksamowego). Związki te, z powodu ich zdolności do tworzenia ze sobą komplementarnych cyklicznych wiązań wodorowych, są potencjalnie użytecznym materiałem budulcowym większych układów supramolekularnych. Odpowiednie układy modelowe otrzymano z optycznie czynnych 1,2-diamin, które poddano acylowaniu chlorooksooctanem etylu, a następnie otrzymane półprodukty tionowano...
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Enhancement of ibuprofen solubility and skin permeation by conjugation with l-valine alkyl esters
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Separation of fatty acids, their methyl esters and triacylglycerols by non-aqueous electrochromatography and HPLC.
PublikacjaElektrochromatografię kapilarną (CEC) oraz HPLC w odwróconym układzie faz zastosowano do rozdzielenia wolnych kwasów tłuszczowych, ich estrów metylowych oraz triacylogliceroli TAG. Zaproponowano własną konstrukcję zestawu laboratoryjnego do CEC oraz sposób preparowania mikrokolumn o średnicy 100 mm i długości złoża (Hypersil ODS 3 mm) 200 mm. Z porównania względnych czasów retencji TAG rozdzielanych technikami CEC i HPLC przy użyciu...
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Utilization of rapeseed pellet from fatty acid methyl esters production as an energy source
PublikacjaRapeseed pellet – crushed seed residue from oil extraction is a by-product of fatty acid methyl esters production process. As other types of biomass, it can either be burned directly in furnaces or processed to increase its energetic value. Biomass is renewable, abundant and has domestic usage; the sources of biomass can help the world reduce its dependence on petroleum products, fossil coal and natural gas. Energetically effective...
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Synthesis of Fatty Acid Esters of Selected Higher Polyols Over Homogeneous Metallic Catalysts
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Selective monoprotection of 1,4,7,10-tetraazacyclododecane via direct reactions with 4-nitrophenyl active esters
Publikacja1,4,7,10-tetraazacyklododekan jest cykliczną tetraaminą. Z chemicznego punktu widzenia wszystkie atomy azotu posiadają takie same właściwości fizykochemiczne. Jedyną różnicę stanowią ich właściwości kwasowo-zasadowe. Cyklen posiada dwa atomy azotu o obniżonej zasadowości. Właściwość ta z powodzeniem wykorzystywana jest w reakcjach jednoczesnej selektywnej substytucji dwóch atomów w pozycji 1 i 7. W przypadku bezpośredniej reakcji...
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Structure-property relationships disclosed in the family of acridinium esters – chemiluminogenic molecules of great practical importance
PublikacjaAcridinium esters (AE), since their introduction to the analytics 30 years ago, make one of the most important groups of chemiluminogenic (CL) systems, that have been employed in medical diagnostics and environmental analysis today. So far, however, no systematic studies on the structureproperty relationships were carried out in this family of compounds. The latter features likely determine their practical utility and facilitate...
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The new esters derivatives of betulin and betulinic acid in epidermoid squamous carcinoma treatment – In vitro studies
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Tribological characterisation of plant oil derived fatty acid esters of higher polyols: Comparative experimental study
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Determination of volatile fatty acid ethyl esters in raw spiritsusing solid phase microextraction and gas chromatography
PublikacjaPrzedstawiono opracowanie i opymalizację metody analitycznej oznaczania estrów etylowych kwasów tłuszczowych w destylatach rolniczych różnej jakości lub wyprodukowanych z różnych surowców. W badaniach wykorzystywano technikę mikroekstrakcji do fazy stacjonarnej (HS-SPME) oraz kapilarnej chromatografii gazowej (CGC) z detektorem płomieniowo-jonizacyjnym (FID). Ekstrakcja związków lotnych prowadzona była według opracowanej procedury,...
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Statistical optimization of the synthesis of plant-derived fatty acid esters of TMP over homogeneous organometallic tin catalyst
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New Selective Peptidyl Di(chlorophenyl) Phosphonate Esters for Visualizing and Blocking Neutrophil Proteinase 3 in Human Diseases
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Esters of p-nitrophenol in synthesis of 1-N-monoamide and 1,7-bis-N,N-amide derivatives of 1,4,7,10-tetraazacyclododecane
PublikacjaW artykule opisana została synteza acylowych pochodnych 1,4,7,10-tetraazacyklododekanu przy pomocy estrów aktywnych. W bezpośredniej reakcji estrów 4-nitrofenylowych z cyklenem prowadzonej w bardzo łagodnych warunkach otrzymano pochodne mono i dipodstawienia z bardzo dobrymi wydajnościami. Zbadano również wpływ różnych parametrów na dystrybucję produktów.
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Supramolecular structures of bis-thionooxalamic acid esters derived from (±)-cyclohexane-1,2-diamine and (±)-1,2-diphenylethylenediamine
PublikacjaZsyntezowano dwa racemiczne estry kwasu bis(tiooksamowego) i zbadano ich sposób upakowania w sieci krystalicznej. Analiza rentgenograficzna monokryształów badanych związków wykazała, że organizują się one w jednowymiarowe struktury, które tworzone są przez molekuły o przeciwnej chiralności, połączone za pomocą trójcentrowych wiązań wodorowych C=S...NH...O=C. Powstające agregaty są dodatkowo stabilizowane przez słabe oddziaływania...
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Microstructural behavior of water-in-oil emulsions stabilized by fatty acid esters of propylene glycol and zinc fatty acid salts
PublikacjaZbadano wpływ składu emulgatorów acylopropylenoglikolowych, modyfikowanych mydłami cynku, na charakter przemian strukturalnych jakim ulegają emulsje W/O stabilizowane przez takie emulgatory. Badano zarówno etap emulgowania jak i mikrostrukturę oraz właściwości reologiczne otrzymanych emulsji.
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Indirect Determination of MCPD Fatty Acid Esters in Lipid Fractions of Commercially Available Infant Formulas for the Assessment of Infants’ Health Risk
PublikacjaMCPD esters are intensively investigated food lipid contaminants for over a decade. Concern related to their presence in various types of food products is related to the fact that possible free MCPD release from its esterified form during digestion may lead to elevated daily intake of these toxicants.Special attention should be devoted into powdered infant formulas, which contain significant amounts of refined vegetable oils, likely...
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Determination of 3-MCPD and 2-MCPD esters in edible oils, fish oils and lipid fractions of margarines available on Polish market
Publikacja3-monochloropropane-1,2-diol (3-MCPD) and 2-monochloropropane-1,3-diol (2-MCPD) are intensively investigated food contaminants, which recently emerged as a serious problem within the discovery of high levels of their fatty acid esters in lipid samples. In order to monitor the concentrations of mentioned toxicants in edible oils and fats, several analytical methods have been developed so far. This paper presents the screening research...
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Procedure for and results of simultaneous determination of aromatic hydrocarbons and fatty acids methyl esters in diesel fuels by high performance liquid chromatography
PublikacjaW pracy przedstawiono taki sposób modyfikacji metody EN-12916 /ASTM D-6591, który zapewnia jednoczesne oznaczenie poszczególnych grup węglowodorów aromatycznych, całkowitej zawartości węglowodorów poliaromatycznych oraz zawartości FAME w oleju napędowym. Stosuje się nadal detektor refraktometryczny i elucję n-heptanem, jednak przepływ zwrotny eluentu jest wykonywany po elucji policyklicznych węglowodorów aromatycznych. Dodatkowo...
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Novel fast analytical method for indirect determination of MCPD fatty acid esters in edible oils and fats based on simultaneous extraction and derivatization
PublikacjaA novel method for indirect determination of MCPD esters levels in lipid samples has been developed. The method is based on combination of extraction and derivatisation in the same sample preparation step. It is achieved by the application of diethyl ether as extraction solvent for isolation of released from esterified forms analytes from water phase and dilution solvent for solid PBA – derivatisation agent. It is a noteworthy...
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Application of safirinium N-hydroxysuccinimide esters to derivatization of peptides for high-resolution mass spectrometry, tandem mass spectrometry, and fluorescent labeling of bacterial cells
PublikacjaMass spectrometry methods are commonly used in the identification of peptides and biomarkers. Due to a relatively low abundance of proteins in biological samples, there is a need for the development of novel derivatization methods that would improve MS detection limits. Hence, novel fluorescent N-hydroxysuccinimide esters of dihydro-[1,2,4]triazolo[4,3-a]pyridin-2-ium carboxylates (Safirinium P dyes) have been synthesized. The...
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Valence and ionic lowest-lying electronic states of small esters studied by high resolution vacuum ultraviolet photoabsorption, photoelectron spectroscopy and ab initio calculations
PublikacjaEsters are an important class of oxygenated volatile organic compounds used in food flavorings, perfumes and other cosmetic products. They are present in fruits and pheromones and are emitted to the atmosphere naturally. Esters are also formed in the atmosphere as a product of the oxidation of ethers. Some of them form poly-molecule chains and are used in plastics. Phosphoesters form DNA backbone, while nitroesters are known for...
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Development and validation of a method for the simultaneous analysis of fatty acid ethyl esters, ethyl sulfate and ethyl glucuronide in neonatal meconium: application in two cases of alcohol consumption during pregnancy
PublikacjaAlcohol consumption during pregnancy constitutes one of the leading preventable causes of birth defects and neurodevelopmental disorders in the exposed children. Fatty acid ethyl esters (FAEEs), ethyl glucuronide (EtG) and ethyl sulfate (EtS) have been studied as potential biomarkers of alcohol consumption. However, most analytical approaches proposed for their analysis in meconium samples consist of separated extraction procedures...
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The activity of latent benzoperimidine esters to inhibit P-glycoprotein and multidrug resistance-associated protein 1 dependent efflux of pirarubicin from several lines of multidrug resistant tumor cells.
PublikacjaZaprezentowano wyniki badań biologicznych przeprowadzonych dla nowej grupy związków: estrów benzoperymidyny z zastosowaniem wybranych linii komórek nowotworowych: wrażliwych i opornych o oporności P-gp-zależnej, MRP1-zależnej i o oporności związanej z nadekspresją białek MRP1/LRP. Metodą spektrofluorymetryczną zbadano zdolność estrów benzoperymidyny do hamowania eksportu aktywnego pirarubicyny z komórek opornych. Estry benzoperymidyny...
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Evaluation of the geranyl esters-containing pheromone traps used for monitoring Elateridae family beetles in crops Ocena pułapek feromonowych zawierających estry geranylu stosowanych do monitorowania chrząszczy z rodziny Elateridae w uprawach
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Complexation of amino acids derivatives in water by calix[4]arene phosphonic acids
PublikacjaSeries of the calix[4]arene phosphonic acids with various substituents at the lower rim was synthesized. Complexing properties of these receptors towards methyl esters of six amino acids strongly depended on the calix[4]arene conformation flexibility. The complex formation processes were monitored using 1H NMR spectroscopy (deuterated phosphate buffer at pD 7.3, 22 oC) and association constant values were evaluated. Inherently...
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Rapid and Green Separation of Mono- and Diesters of Monochloropropanediols by Ultrahigh Performance Supercritical Fluid Chromatography–Mass Spectrometry Using Neat Carbon Dioxide as a Mobile Phase
PublikacjaThis study demonstrates the effect of column selectivity and density of supercritical carbon dioxide (SC-CO2) on the separation of monochloropropanediol (MCPD) esters, known as food toxicants, using SC-CO2 without addition of cosolvent in ultrahigh performance supercritical fluid chromatography–mass spectrometry (UHPSFC-MS). This study shows that over 20 2-monochloropropanediol (2-MCPD) and 3-monochloropropanediol (3-MCPD) mono-...
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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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On the electronic structure of methyl butyrate and methyl valerate
PublikacjaWe present novel results of the analysis of the electronic structure of two aliphatic esters: methyl butyrate and methyl valerate. High-resolution photoabsorption spectra were collected and analyzed over the energy range 4.0–10.8 eV and showed for both the molecules not only a clear band of the HOMO to LUMO transition, but also vibronic structure associated with the first Rydberg-valence transition. Photoelectron spectra recorded...
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Synthesis and antimicrobial activity of amino acid and peptide derivatives of mycophenolic acid
PublikacjaThe series of 16 novel amino acid and peptide mycophenolic acid (MPA) derivatives was obtained as potential antibacterial agents. Coupling of MPA with respective amines was optimized with condensing reagents such as EDCI/DMAP and T3P/TEA. Amino acid analogs were received both as methyl esters and also with the free carboxylic group. The biological activity of the products was tested on five references bacterial strains: Klebsiella...
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Preparation of Pseudopeptides Building Blocks with Retro-Thioamide Bond Mediated via Thiocarbamoyl Meldrum's Acid
PublikacjaAn easy and efficient synthesis of pseudo tripeptide containing a thiomalonamide moiety was developed. Isothiocyanate derivatives of amino acids react smoothly with 2,2-dimethyl-1,3-dioxane-4,6-dione yielding new thiocarbamoyl Meldrum's acids. Thermal decomposition of this new Meldrum's acid derivatives generate thiocarbamoyl ketenes, which acylate amino acid esters to give pseudo tripeptides.
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Development of Safirinium dyes for new applications: fluorescent staining of bacteria, human kidney cells, and the horny layer of the epidermis
PublikacjaLow-molecular synthetic fluorophores are convenient tools in bioimaging applications. Several derivatives of Safirinium dyes as well as their reactive N-hydroxysuccinimide (NHS) esters bearing diverse substituents were synthesized and evaluated experimentally in terms of their lipophilicity by means of reverse-phase and immobilized artificial membrane high-performance liquid chromatography. Subsequently, the selected compounds...
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Alkanethiolates of Group 1,2, and 13-15 Metals
PublikacjaThis manuscript is an update to the earlier Science of Synthesis contribution describing methods for the synthesis of alkanethiolates of group 1, 2, and 13-15 metals. Alkanethiolates can be converted into S-alkyl thiocarboxylic acid esters, 1-thioglycosides, S-alkyl thiosulfinates, tetrahydro-1,4-thiazine-3-ones, sulfides, disulfides, sulfonium salts, dithioacetals and dithioketals, etc. These transformations are accomplished by...
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Synthesis and biological activity of mycophenolic acid-amino acid derivatives
PublikacjaIn search of new immunosuppressants, mycophenolic acid (MPA) was coupled with amino acid methyl esters followed by hydrolysis to analogs bearing free carboxylic groups. The obtained compunds were tested in vitro as growth inhibitors of lymphoid cell line (Jurkat) and human peripheral blood mononuclear cells (PBMC) from healthy donors. According to obtained results recovering of free carboxylic group increased their activity. Additionally,...
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Greener organic solvents in analytical chemistry
PublikacjaThe paper presents the most recent advances in analytical applications of greener organic solvents. Substitution of problematic solvents with more benign organic ones is much easier than shifting to technique applying alternative solvents, such as ionic liquids or supercritical fluids. In the area of liquid chromatography greener mobile phases, much attention is given to application ethanol or acetone instead of acetonitrile. Solvent-based...
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Transition-Metal-Promoted Oxidative Cyclization To Give 1,2,4-Trisubstituted Carbazole Scaffolds
PublikacjaHerein, we describe the synthesis of a 1,2,4-trisubstituted carbazole core from 5-(1H-indol-3-yl)-3-oxopentanoic acid esters or amides. For oxidative cyclization, we tested two different approaches. First, we used manganese triacetate as a conventional moderate oxidizer to ensure the radical course of the reaction. Second, we examined the use of a more complex oxidizing agent I2/Me(OTf)3. In both cases, formation of a fused-ring...
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Rapeseed oil methyl ester production in an individual household
PublikacjaFatty acid methyl esters, commonly known as biodiesel, are a cheap and environmental-friendly fuel substitute for diesel engines. Aside from industrial production, individual biodiesel manufacturing is also and important method of fulfilling the requirements of EU Parliament directive no. 2003/30/WE about supporting the use of renewable fuels in transport. Individual FAME production guarantees easy access to the main raw material...
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Anticancer Properties of Amino Acid and Peptide Derivatives of Mycophenolic Acid
PublikacjaBackground: Although Mycophenolic Acid (MPA) is applied as prodrugs in clinic as an immunosuppressant, it also possesses anticancer activity. MPA acts as Inosine-5’-Monophosphate Dehydrogenase (IMPDH) inhibitor, where the carboxylic group at the end of the side chain interacts with Ser 276 of the enzyme via hydrogen bonds. Therefore, MPA derivatives with other polar groups indicated high inhibition too. On the other hand, potent...
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Selected Methods for the Chemical Phosphorylation and Thiophosphorylation of Phenols
PublikacjaThis Focus Review gathers together a selection of methods for the chemical phosphorylation of phenols that employ three‐ and four‐coordinate phosphorus compounds. Phosphorylated scaffolds can exhibit enhanced properties compared to their non‐phosphorylated analogues, such as increased biological activity and increased/decreased solubility; as such, phosphorus compounds have gained more and more interest in organic and medicinal...
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Analytical chemistry with biosolvents
PublikacjaOne of the current trends in green analytical chemistry is the introduction of green solvents, some of which are biobased. At the same time, the development of the biorefinery concept has allowed more biochemicals to be obtained with increased efficiency and from a wider range of feedstocks. The first examples of the use of biosolvents in analytical applications included extractions performed with alcohols, esters, and terpenes....
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Dual functionality of amphiphilic 1-alkyl-3-methylimidazolium hydrogen sulfate ionic liquids: surfactants with catalytic function
PublikacjaA series of amphiphilic 1-alkyl-3-methylimidazolium hydrogen sulfate ionic liquids were synthesized. Acidic hydrogen sulfate ionic liquids with the alkyl chains C6–C14 are characterized by good surface properties. Their surface properties (adsorption and micellization parameters, degree of ionization of micelles, Krafft temperatures and thermodynamic parameters) were determined. Synthesized ionic liquids were applied as a co-catalyst...
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Separation and determination of the group-type composition of modern base and lubricating oils with a wide range of polarity, especially emitted to the environment
PublikacjaLubricating oils are composed of base oils (>85% v/v) and enriching additives (<15% v/v). Three types of base oils may be distinguished: 1) traditional bases (obtained by low-volatile fractions from crude oil distillation refining), 2) synthetic bases (mainly poly-alpha-olefins, sometimes esters, especially succinic acid esters), 3) bases of natural origin (especially obtained from refined plant oils). The bases of natural origin...
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Kobieta ciężarna i alkohol-toksyczny związek. Smółka noworodków jako materiał w diagnostyce spożywania alkoholu w czasie ciąży
PublikacjaKażda ilość alkoholu spożyta przez ciężarną kobietę może spowodować poronienie, przedwczesny poród, patologię łożyska, zahamowanie wzrostu wewnątrzmacicznego płodu i wystąpienie licznych wad wrodzonych wywołanych alkoholem, określanych wspólnie mianem spektrum płodowych zaburzeń alkoholowych - FASD. Mogą one objawiać się zaburzeniami psychicznymi i/lub fizycznymi. Współczesna diagnostyka u noworodków zespołu FASD opiera się najczęściej...
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Cold-adapted bacterial lipolytic enzymes and their applications
PublikacjaLipolytic enzymes, esterases and lipases catalyze the hydrolysis and transesterification of fatty acid esters. This class of enzymes is the most important group of biocatalysts for biotechnological applications. From this perspective, coldactive lipolytic enzymes from cold adapted bacteria display attractive properties for some industrial purposes, including high catalytic activity at low temperatures and low thermostability. To...
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Cuticular lipids of insects as potential biofungicides
PublikacjaThe term ''lipids'' refers to fatty acids, their derivatives and substances related with them biochemically or by the functions in the body. Lipids include compounds with different chemical structure. There are lipids with structures based on long-chain carboxylic acids and their direct derivatives, namely: fatty acids, alkanes, some alkenes, aldehydes and long chain alcohols and their derivatives (esters). The variety of lipid...