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Search results for: PYRUVIC ACID
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The Role of Molecular Structure in Monte Carlo Simulations of the Secondary Electron Yield and Backscattering Coefficient from Methacrylic Acid
PublicationIn this paper, we show the influence of the chemical structure of four different conformers on the secondary electron emission and backscattering of an electron beam from a gel of methacrylic acid. The conformers have different permanent dipole moments, which determines the cross sections for elastic collisions with electrons. The cross sections are used in Monte Carlo simulations of an electron beam, which enters the gel of methacrylic...
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Influence of temperature and anion type on thermophysical properties of aqueous solutions of morpholine based amino acid ionic liquids
PublicationDensities and sound velocities of aqueous solutions of N-butyl-N-methylmorpholine based amino acid ionic liquids (AAILs), including N-acetyl-L-alanine, N-acetyl-Lvalinate, N-acetyl-L-leucinate, and N-acetyl-L-izoleucinate anions were measured at a temperature from 293.15 to 313.15 K at 5 K intervals and atmospheric pressure. These data were used to calculate the apparent molar volumes and the apparent molar compressibilities in...
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Meldrum’s acid assisted formation of tetrahydroquinolin‑2‑one derivatives a short synthetic pathway to the biologically useful scaffold
PublicationA new method for the preparation of tetrahydroquinolin-2-one derivatives is presented. This approach involves a two-step reaction between enaminones and acylating agents, immediately followed by electrophilic cyclization, all within a single synthesis procedure, eliminating the need to isolate intermediates. The entire process is facilitated by the use of acyl Meldrum’s acids which not only shortens the preparation time of the...
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Diphosphination of CO2 and CS2 mediated by frustrated Lewis pairs - catalytic route to phosphanyl derivatives of formic and dithioformic acid
PublicationThe first example of CO2 diphosphination is described. Reactions of unsymmetrical diphosphanes with CE2 (E = O, S) catalyzed by BPh3 insert a CE2 molecule into the P-P bond with formation of the products of the general formula R2P-E-C(=E)-PR2. The obtained CO2 adducts arise from synergistic interaction of diphosphane and borane with CO2 molecule.
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Competitive Adsorption of a Binary VOC Mixture from the Gas Phase onto Activated Carbon Modified with Malic Acid
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Can local infiltration analgesia supplemented with tranexamic acid reduce blood loss during total knee arthroplasty?
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Propensity of salicylamide and ethenzamide cocrystallization with aromatic carboxylic acids
PublicationThe cocrystallization of salicylamide (2-hydroxybenzamide, SMD) and ethenzamide (2-ethoxybenzamide, EMD) with aromatic carboxylic acids was examined both experimentally and theoretically. The supramolecular synthesis taking advantage of the droplet evaporative crystallization (DEC) technique was combined with powder diffraction and vibrational spectroscopy as the analytical tools. This led to identification of eleven new cocrystals...
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Electric chips for rapid detection and quantification of nucleic acids
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Biodegradability of modified emulsifiers - esters of polyols and fatty acids
PublicationBadano 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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Ion Chromatography in Environmental Analysis of Selected Organic Acids
PublicationLow molecular mass carboxylic acids (LCAs) occur in many environmental compartments dueto natural processes and human activity. When volatile and nonvolatile acids are to be monitored then liquidchromatography, including ion chromatography seems a method of choice. At high pH the acids are inionized form and can be separated as carboxylats by means of anion exchange chromatography. LCAs canalso be separated at low pH by ion exclusion...
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Bile Acids: Key Players in Inflammatory Bowel Diseases?
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Fatty acids as molecular carriers in cleavable antifungal conjugates
PublicationConjugates composed of C2-18 fatty acid (FA) residues as a molecular carrier and 5-fluorocytosine (5-FC) as an active agent, released upon the action of intracellular esterases on the ester bond between FA and “trimethyl lock” intramolecular linker, demonstrate good in vitro activity against human pathogenic yeasts of Candida spp. The minimal inhibitory concentrations (MIC) values for the most active conjugates containing caprylic...
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S-thioacyldithiophosphates in the synthesis of thiohydroxamic acids and O-thioacylhydroxylamines
PublicationDitiofosforany tioacylu to trwałe, łatwo osiągalne z kwasów karboksylowych środki tioacylujące. Z powodu ich niskiej reaktywności wobec nukleofili tlenowych i wysokiej wobec nukleofili azotowych znalazły zastosowanie w syntezie kwasów tiohydroksamowych bezpośrednio z hydroksyloamin z niechronioną grupą hydroksylową. W przypadku dużej zawady przestrzennej można otrzymać O-tioacylohydroksyloaminy.
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Mechanism of the reaction of Lawesson's reagent with N-alkylhydroxamic acids
PublicationIdentyfikacja fosforowych produktów powstających w reakcji kwasów hydroksamowych z odczynnikiem Lawessona pozwoliła ustalić mechanizm tytułowej reakcji. Wykorzystano w tym celu spektroskopię 31P NMR. Wzorce labilnych produktów otrzymano na niezależnej drodze syntetycznej lub przeprowadzono je w trwałe pochodne, które wyizolowano z mieszanin reakcyjnych. Produktem przejściowym badanej reakcji okazał się odpowiedni O-ditiofosfonylowany...
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Flexural behaviour of concrete slabs reinforced with FRP bars in experiments and according to aci ACI 440.1R guide
PublicationThe paper presents research conducted on two concrete slabs reinforced with the carbon composite bars and two other concrete slabs reinforced with basalt composite bars. The carbon bars were plain, while the basalt ones were ribbed. The slabs were experimentally investigated in the flexural state of effort with the concentrated forces applied. The results are compared with the analytical solution proposed in the guide ACI 440.1R-06...
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Special hearing aid for stuttering people
PublicationDzięku postępowi w dziedzienie cyfrowego przetwarzania sygnałów możliwe stało zbudowanie subminiaturowego urządzenia łączącego funkcje aparatu słuchowego i korektora mowy. Takie urządzenie, mimo niewielkich rozmiarów, jest w stanie wykonywać skomplikowane alggorytmy a jego oprogramowanie może być łatwo zmieniane. W pracy skupiono się na zagadnieniach związanych z opracowniem prototypu i implementacją algorytmów korekcji słuchu...
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Contactless hearing aid designed for infants
PublicationIt is a well known fact that language development through home intervention for a hearing-impaired infant should start in the early months of a newborn baby's life. The aim of this paper is to present a concept of a contactless digital hearing aid designed especially for infants. In contrast to all typical wearable hearing aid solutions (ITC, ITE, BTE), the proposed device is mounted in the infant's bed with any parts of its set-up...
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Molecular Heteroconjugation Equilibria in (n-Butylamine + Acetic Acid) Systems in Binary (Dimethyl Sulfoxide + 1,4-Dioxane) Solvent Mixtures
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Bimodal Nd-Doped LuVO4 Nanoprobes Functionalized with Polyacrilic Acid for X-Ray Computed Tomography and NIR Luminescent Imaging
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Ibotenic acid lesion of the ventral hippocampus differentially affects dopamine and its metabolites in the nucleus accumbens and prefrontal cortex in the rat
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Enhanced Activity and Sustained Release of Protocatechuic Acid, a Natural Antibacterial Agent, from Hybrid Nanoformulations with Zinc Oxide Nanoparticles
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The type of blood used to feed Aedes aegypti females affects their cuticular and internal free fatty acid (FFA) profiles
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Proline, glutamic acid, and leucine rich protein 1 (PELP1) expression in deep paravertebral muscles in idiopathic scoliosis girls
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Investigation of OH radicals formation on the surface of TiO2/N photocatalyst at the presence of terephthalic acid solution. Estimation of optimal conditions
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Molecular heteroconjugation equilibria in (n-butylamine + acetic acid) systems in binary (dimethyl sulfoxide + 1,4-dioxane) solvent mixtures
PublicationWyznaczono stałe kwasowe Ka(HA), Ka(BH+) oraz stałe równowagi KAHA-, KBHE+ i KAHB, w układach (n-butyloamina + kwas octowy) bez przeniesienia protonu w binarnych mieszaninach rozpuszczalników (DMSO + 1,4-dioksan). Wartości stałych wyznaczono z wykorzystaniem metody miareczkowania potencjometrycznego przy stałej sile jonowej. Stwierdzono, iż stałe heterokoniugacji molekularnej w badanych mieszaninach rozpuszczalników są liniowo...
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Supramolecular structures of bis-thionooxalamic acid esters derived from (±)-cyclohexane-1,2-diamine and (±)-1,2-diphenylethylenediamine
PublicationZsyntezowano 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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Application of hollow mesoporous carbon nanospheres as an high effective adsorbent for the fast removal of acid dyes from aqueous solutions
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Exploring ion-ion preferences through structure-property correlations: amino acid-derived, bis(guanidinium) disiloxane salts
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Raman and surface-enhanced Raman spectroscopy investigation of vasopressin analogues containing 1-aminocyclohexane-1-carboxylic acid residue
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Cations of amino acid alkyl esters conjugated with an anion from the group of NSAIDs – As tunable pharmaceutical active ionic liquids
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Prebiotic Potential of Oligosaccharides Obtained by Acid Hydrolysis of α-(1→3)-Glucan from Laetiporus sulphureus: A Pilot Study
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Comparison and Optimization of Saccharification Conditions of Alkaline Pre-Treated Triticale Straw for Acid and Enzymatic Hydrolysis Followed by Ethanol Fermentation
PublicationThis paper concerns the comparison of the efficiency of two-stage hydrolysis processes, i.e., alkaline pre-treatment and acid hydrolysis, as well as alkaline pre-treatment followed by enzymatic hydrolysis, carried out in order to obtain reducing sugars from triticale straw. For each of the analyzed systems, the optimization of the processing conditions was carried out with respect to the glucose yield. For the alkaline pre-treatment,...
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Molecular and structural basis of inner core lipopolysaccharide alterations in Escherichia coli: incorporation of glucuronic acid and phosphoethanolamine in the heptose region.
PublicationIt is well established that lipopolysaccharide (LPS) often carries nonstoichiometric substitutions in lipid A and in the inner core. In this work, the molecular basis of inner core alterations and their physiological significance are addressed. A new inner core modification of LPS is described, which arises due to the addition of glucuronic acid on the third heptose with a concomitant loss of phosphate on the second heptose. This...
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Influence of hydrochloric acid concentration and type of nitrogen source on the electrochemical performance of TiO2/N-MoS2 for energy storage applications
PublicationIn this work, nitrogen-doped molybdenum sulfide was directly deposited on titanium dioxide nanotubes substrate (TiO2/N-MoS2) during hydrothermal synthesis. The study focuses on the influence of hydrochloric acid concentration used for the synthesis, with the results indicating its essential role in thioacetamide hydrolysis and thus in the effectiveness of the N-MoS2 deposition. The electrode material itself is characterized by...
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No Evidence for Sex-specificity in Vitamin C, E and Fatty Acid Content of Human Milk from Healthy Polish Mothers
PublicationHuman milk (HM) is a complex fluid that meets the nutritional needs of infants. Its composition idrfs associated with environmental, maternal, and foetal variables. It provides nutrients and bioactive substances, including cytokines, immunoglobulins, and constituents with antioxidative properties. Boys are reportedly more susceptible to oxidative stress. This study aimed to determine the relationship between infant sex and the...
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Overcoming carboxylic acid inhibition by granular consortia in high-load liquefied food waste fermentation for efficient lactate accumulation
PublicationGranular sludge, a self-aggregating spherical biofilm, possesses better stability compared to flocculent sludge under extreme conditions. This study compared the ability of anaerobic granular sludge (AnGS) and flocculent waste activated sludge (WAS) to convert food waste (FW) into highly-valuable optically active lactic acid (LA), a central and versatile intermediate platform molecule. Different loadings (30–60 g volatile suspended...
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Cold plasma treatment of tannic acid as a green technology for the fabrication of advanced cross-linkers for bioactive collagen/gelatin hydrogels
PublicationTannic acid (TA) is a natural compound studied as the cross-linker for biopolymers due to its ability to form hydrogen bonds. There are different methods to improve its reactivity and effectiveness to be used as a modifier for biopolymeric materials. This work employed plasma to modify tannic acid TA, which was then used as a cross-linker for fabricating collagen/gelatin scaffolds. Plasma treatment did not cause any significant...
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Plasma free amino acid profiling as metabolomic diagnostic and prognostic biomarker in paediatric cancer patients: a follow‑up study
PublicationAmino acids (AAs) play a crucial role in cancer cell metabolism. Levels of 22 plasma AAs at the time of diagnosis and after treatment were established among 39 pediatric cancer patients and 33 healthy children. Glutamic acid levels decreased and tryptophan levels increased during treatment. Cancer patients presented significantly lower levels of glutamine and leucine post-treatment while levels of 12 other AAs were higher comparing...
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Efficacy of tranexamic acid supplemented with local infiltration analgesia in reducing blood loss in patients undergoing unicompartmental knee arthroplasty
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Efficacy of tranexamic acid supplemented with local infiltration analgesia in reducing blood loss in patients undergoing unicompartmental knee arthroplasty.
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Peroxidative metabolism of fatty acids in the course of tick-borne encephalitis
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Applicability of phenolic acids as effective enhancers of cocrystals solubility of methylxanthines
PublicationApplicability of phenolic acids as potential cocrystal formers for methylxanthine derivatives was analyzed both in terms of cocrystallization probabilities and solubility advantage. The cocrystal formation abilities were evaluated using mixing enthalpy estimated within the conductor like screening model for real solvents (COSMO-RS) framework. The solubility improvement of potential cocrystals was estimated by formulation of the...
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Calibration of POCIS and PASSIL passive samplers – influence of humic acids
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Green Analytical Chemistry in Determination of Volatile Fatty Acids in Wastewater
PublicationCharakterystyka metodyk oznaczania lotnych kwasów tłuszczowych w próbkach wodnych, opierających się na Zasadach Zielonej Chemii. Opis zastosowania techniki bezpośredniego dozowania próbki wodnej do chromatografu gazowego, techniki analizy fazy nadpowierzchniowej oraz techniki mikroestrakcji do fazy stacjonarnej.
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Occurrence and Determination of Volatile Fatty Acids in Wastewater of Different Origin
PublicationOpracowano metodykę oznaczania krótkołańcuchowych alifatycznych kwasów monokarboksylowych w ściekach rożnego pochodzenia stosując ekstrakcję za pomocą eteru metylo-tert-butylowego na etapie przygotowania próbek i chromatografię gazową z kolumną kapilarną Stabilwax-DA i Rtx-624, natomiast na etapie detekcji stosowano spektrometr mas.
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Recent advances in extraction and analysis procedures of natural chlorogenic acids
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Occurrence and Determination of Volatile Fatty Acids in Landfill Leachate and Gas
PublicationIn landfills containing biological matter volatile fatty acids (VFAs) are generated at high rate at the early stage of waste disposal and their content in leachate is high as compared to the leachate from old parts of landfill since they are converted to methane gas. Monitoring of the leachate for the content of VFAs can help determine the processes occurring in waste and possible effect of the leachate on the environment in the...
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α-Amino Acids In Water: A Review Of VCD And ROA Spectra
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Hydration of amino acids: FTIR spectra and molecular dynamics studies
PublicationThe hydration of selected amino acids, alanine, glycine, proline, valine, isoleucine and phenylalanine, has been studied in aqueous solutions by means of FTIR spectra of HDO isotopically diluted in H2O. The difference spectra procedure and the chemometric method have been applied to remove the contribution of bulk water and thus to separate the spectra of solute-affected HDO. To support interpretation of obtained spectral results,...
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The Role of Electron Transfer in the Fragmentation of Phenyl and Cyclohexyl Boronic Acids
PublicationIn this study, novel measurements of negative ion formation in neutral potassium-neutral boronic acid collisions are reported in electron transfer experiments. The fragmentation pattern of phenylboronic acid is comprehensively investigated for a wide range of collision energies, i.e., from 10 to 1000 eV in the laboratory frame, allowing some of the most relevant dissociation channels to be probed. These studies were performed in...