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Search results for: CARMINIC ACID
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Phenazine - 2,6-dihydroxybenzoic acid (1/1)
PublicationOtrzymano krystaliczny kompleks fenazyny z kwasem 2,6-dihydroksybenzoesowym o stechiometrii 1:1. Badania struktury kompleksu za pomocą metod rentgenograficznych wykazały, że powiązane wiązaniami wodorowymi typu OH...N cząsteczki fenazyny układają się w stosy, które stabilizowane są poprzez oddziaływania typu π-π pierścieni aromatycznych. Cząsteczki kwasu zajmują przestrzenie kanałów tworzonych pomiędzy kolumnami pierścieni aromatycznych...
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The 2:1 cocrystal of benzamide and pentafluororbenzoic acid
PublicationKrystaliczna struktura centrosymetrycznej supermolekuły składa się z czterech cząsteczek benzamidu oraz dwóch kwasu karboksylowego, które powiązane są ze sobą za pomocą wiązań wodorowych typu O-H...O oraz N-H...O.
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May dithiophosphoric acid participate in the set process?
PublicationZastosowano otrzymane S-tioacyloditiofosforany jako odczynniki tioacylujące do syntezy kwasów tiohydroksamowych. Dla większości N-alkilohydroksyloamin produktem tej reakcji były żądane kwasy tiohydroksamowe. Natomiast gdy substratem jest hydroksyloamina zawierająca duży objętościowo podstawnik na atomie azotu lub gdy posiada dwa podstawniki na atomie azotu w reakcji tej tworzą się wyłącznie odpowiednie O-tioacylohydroksyloaminy....
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Easy formation of acyl-Meldrum's acid anhydride
PublicationAcyl Meldrum's acid are usually a good source of ketenes upon definite thermal composition. However we treated acyl-Meldrum's acid with the Lewis acid and we observed formation of 5[[(2,2-dimethyl-4,6-dioxo-1,3-dioxan 5 ylidene)(acyl/arylamino)mathoxy](acyl/arylamino)methylene]-2,2dimethyl-1,3-dioxane-4,6 dione which means acyl-Meldrum's acid anhydride. The chemical properities of acyl-Meldrum's acid anhydride were explored.
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(S)-N-Nitrosoazetidine-2-carboxylic acid.
PublicationAnaliza rentgenograficzna monokryształów kwasu (S)-N-nitozoazetydyno-2-karboksylowego wykazała, że reszta N-nitrozoaminowa przyjmuje konfigurację E. Azetydynowy atom azotu jest nieznacznie piramidalny. Cząsteczki w sieci krystalicznej oddziałują ze sobą poprzez wiązania wodorowe pomiędzy atomem tlenu grupy nitrozowej i atomem wodoru grupy karboksylowej, tworząc polimeryczny łańcuch.
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Hydrogen charging of nitrided steel in acid solution
PublicationKonstrukcyjną stal, azotowaną w wyładowaniu jarzeniowym w mieszaninie gazów o różnej zawartości N2, H2 i Ar, poddawano katodowemu nawodorowaniu w kwaśnym roztworze, imitującym przepracowany olej maszynowy. W pomiarach szybkości przenikania wodoru i ekstrakcji próżniowej określano wpływ azotowanych warstw, odpowiednio, na transport wodoru i na jego nieodwracalne pułapkowanie. W obecności niezdefektowanej warstwy kompaktowych azotków...
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ASCORBIC ACID IN POLYURETHANE SYSTEMS FOR TISSUE ENGINEERING
PublicationThe introduction of the paper was devoted to the main items of tissue engineering (TE) and the way of porous structure obtaining as scaffolds. Furthermore, the significant role of the scaffold design in TE was described. It was shown, that properly designed polyurethanes (PURs) find application in TE due to the proper physicochemical, mechanical and biological properties. Then the use of L-ascorbic acid (L-AA) in PUR systems for...
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New conjugates of mycophenolic acid and their antiproliferative activity
PublicationThe new conjugates of mycophenolic acid (MPA) were obtained in the reaction of N6-(ω-aminoalkyl)adenosines with MPA in the presence of EDCI as a coupling reagent. New compounds 4a–h were evaluated on leukemia cell line (Jurkat) and PBMC from healthy donors. Length of the linker influenced observed activity. The compound 4b possessing 1,3-diamine spacer exhibited the most promising results and can be considered to further investigations.
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Sciences in Cold and Arid Regions
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Agricultural Research in the Arid Areas
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Research in Cold and Arid Regions
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ARID LAND RESEARCH AND MANAGEMENT
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Encapsulation of Amikacin into Microparticles Based on Low-Molecular-Weight Poly(lactic acid) and Poly(lactic acid-co-polyethylene glycol)
PublicationThe aim of this study was to fabricate novel microparticles (MPs) for efficient and long-term delivery of amikacin (AMI). The emulsification method proposed for encapsulating AMI employed low-molecular-weight poly(lactic acid) (PLA) and poly(lactic acid-co-polyethylene glycol) (PLA−PEG), both supplemented with poly(vinyl alcohol) (PVA). The diameters of the particles obtained were determined as less than 30 μm. Based on an in-vitro...
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Optimization of Trans-esterification Process and Characterization of Biodiesel from Soapstock Using Silica Sulfuric Acid as a Heterogeneous Solid Acid Catalyst
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ACI MATERIALS JOURNAL
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The application of Gabor transformation in the harmonic analysis of corrosion processes
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Frequency dispersion of harmonic components of the current of an electrode process
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Fundamental-harmonic impedance of first-order electrode reactions
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Quantum Correlations of a Few Bosons within a Harmonic Trap
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Dependence of harmonic generation on primary wave pressure distribution
PublicationPraca dotyczy numerycznego badania zagadnienia wytwarzania harmonicznych ciśnienia podczas rozchodzenia się fal o skończonej amplitudzie, promieniowanych przez źródła kołowe o różnych rozkładach. Model matematyczny zbudowano w oparciu o równanie KZK. Do numerycznego rozwiązania problemu zastosowano metodę bilansu harmonicznych i metodę różnic skończonych. Analizowano zmiany składowych harmonicznych ciśnienia w obrębie wiązki akustycznej....
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Improving AFM images with harmonic interference by spectral analysis
PublicationPrzedstawiono sposób usunięcia zakłóceń pojawiających się na obrazach uzyskiwanych z mikroskopu sił atomowych (AFM). Przybliżono kilka metod stosowanych do redukcji zakłóceń w obrazach. Następnie opisano zidentyfikowane zakłócenia harmoniczne oraz zaproponowany sposób ich znaczącej redukcji. W pracy zamieszczono szereg obrazów uzyskanych z mikroskopu AFM ilustrujących efekty powodowane zakłóceniami oraz skuteczność zaproponowanej...
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The application of Gabor transformation in the harmonic analysis of corrosion processes.
PublicationZaproponowana została nowa metoda analizy widmowej niestacjonarnych procesów korozyjnych. Analizie poddany został układ modelujący pierwszorzędową reakcję elektrodową. Wykazano, że w przypadku pobudzenia układu liniowo zmieniającym się potencjałem z nałożoną składową sinusoidalną przekształcenie Fouriera nie odzwierciedla zmian amplitudy powstających składowych harmonicznych. Jako rozwiązanie zaproponowana została analiza...
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Corrosion process monitoring by AFM higher harmonic imaging
PublicationThe atomic force microscope (AFM) was invented in 1986 as an alternative to the scanning tunnelling microscope, which cannot be used in studies of non-conductive materials. Today the AFM is a powerful, versatile and fundamental tool for visualizing and studying the morphology of material surfaces. Moreover, additional information for some materials can be recovered by analysing the AFM's higher cantilever modes when the cantilever...
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Improvement of derivatized amino acid detection sensitivity in micellar electrokinetic capillary chromatography by means of acid-induced pH-mediated stacking technique
PublicationDerivatization is a frequently used sample prepara-tion procedure applicable to the enhancement of analyte de-tection sensitivity. Amino acids mostly require derivatization prior to electrophoretic or chromatographic analysis, especial-ly if spectrophotometric detection is used. This study presents an on-line preconcentration technique for derivatized amino acids. The sensitivity of the method was improved by the utilization of...
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Acid–base properties of the crosslinked polysaccharide–polyimine layer deposited on the surface of siliceous material (acid–base properties of the polysaccharide–polyimine layer)
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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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Peroxidative metabolism of arachidonic acid in the course of Lyme arthritis
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VOLTAMMETRIC DETERMINATION OF DEOXYRIBONUCLEIC ACID PRESENCE ON A CARBON ELECTRODE
PublicationThis paper presents a voltammetry as a useful method to analyse DNA from different species. This electrochemical method is well know and used in different analyses. The influence of an area of working electrode and the capacity component, is shown at equals and the measurement. In voltammetry DNA measurement the capacity component is very important and must be taken into consideration. All mathematical analyses were verify at laboratory.
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Serum fatty acid profile in psoriasis and its comorbidity
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Developing nucleic acid-based electrical detection systems
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The Acid Strength of the Lewis‐Brønsted Superacids – A QSPR Study
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Simulation of Force Spectroscopy Experiments on Galacturonic Acid Oligomers
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Acyl Meldrum's acid derivatives: application in organic synthesis
PublicationThis review is focused on one of the most important classes of Meldrum's acid derivatives commonly known as acyl Meldrum's acids. The preparation methods of these compounds are considered including the recently proposed and rather rarely used ones. The chemical properties of acyl Meldrum's acids are described in detail, including thermal stability and reactions with various nucleiophiles. The possible mechanisms of these transformations...
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Chlorogenic Acid Stability in Pressurized Liquid Extraction Conditions
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Therapy with acetylsalicylic acid does not interfere with oral surgery
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Magnetization enhancement in magnetite nanoparticles capped with alginic acid
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Sweet surfactants I: Fatty acid esters of sucralose
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The Characterization of Scaffolds Based on Dialdehyde Chitosan/Hyaluronic Acid
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Synthesis of 2,6-diaminopimelic acid (DAP) and its analogues
PublicationKwas 2,6-diaminopimelinowy jest ważnym aminokwasem biosyntetyzowanym przez bakterie i wyższe rośliny. Liczne fragmenty peptydoglikanu zawierające reszty kwasu diaminopimelinowego wykazują aktywność przeciwnowotworową i/lub immunostymulacyjną. W artykule opisano sposoby syntezy kwasu 2,6-diaminopimelinowego i jego analogi.
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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, a natural hydroxamate siderophore, plays a vital role in iron acquisition for fungi and bacteria. As the simplest natural hydroxamate siderophore, it 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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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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Structured triacylglicerols containing behenic acid: preparation and properties
PublicationNiskokaloryczne lipidy strukturyzowane otrzymano na drodze przeestryfikowania właściwego oleju oliwkowego całkowicie uwodornionym wysokoerukowym olejem rzepakowym (TAG/SLHE) oraz na drodze acydolizy oleju oliwkowego kwasem behenowym (TAG/SLB). Reakcje były katalizowane Lipozyme RM IM. Tłuszcz (TAG/SLHE) charakteryzował się wysoką temperaturą topnienia - 45,5 st. C, natomiast tłuszcz (TAG/SLB) miał temperaturę topnienia 37,5 st.C...
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Dissociation of 2-oxopropanoic acid by low energy electrons
PublicationElectron attachment to molecular target can lead to a variety of negative fragment ions. We experimentally probe the main dissociative electron attachment (DEA) channels in 2-oxopropanoic acid (CH3 - CO - COOH) - an important trace component in the Earth's atmosphere. In our studies we utilise nearly mono-energetic electrons at electron energies from 0 eV up to 15 eV.
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Electron-impact ionization cross section of formic acid
PublicationExperimental electron-impact ionization cross sections of one of the simplest carboxylic acids, formic acid, are presented. The molecular target was studied in two independent experimental setups applying different methods: the total ion collection and the electron–impact mass spectrometry methods. Experimental data were taken at incident electron energies ranging from ionization threshold [11.31 eV; J.C. Traeger, Int. J. Mass...
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Acid site concentrations of the MXenes samples
Open Research DataData contains the pH of 0.01M NaOH solution, before and after mixing with the MXenes samples.
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The influence of the type of composition of PVA-chitosan blends on stability at elevated temperature
Open Research DataThe dataset shows the results of a visual evaluation of chitosan and polyvinyl alcohol composites. The composites were prepared by combining chitosan water solutions, dissolved in selected acids, and polyvinyl alcohol solution, freeze drying, and heating at 150°C dry composites. The results confirm that the chitosan / PVA composites, in which the first...
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Third harmonic index as a diagnostic tool of high-voltage varistors
PublicationThe recommended methods for standard testing of high-voltage varistors demand application of high voltages and intensive currents that is inconvenient and needs extensive power consumption. These methods require metallization of the prepared ZnO structures that increases costs of testing. Another method of varistor quality and endurance evaluation by the third harmonic index measurement at relatively low voltage range has been...
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Quality assessment of high voltage varistors by third harmonic index
PublicationHigh voltage varistors that consist of grained ZnO have to be tested before assembling into a surge arrester. The existing methods demand a usage of high voltages and intensive currents that is inconvenient, destructive and needs extensive power consumption. Additionally, these methods require metallization of the prepared varistor structures that increases costs. We propose another method of varistors quality assessments by a...
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Selective Harmonic Elimination PWM For a Cascaded Multi-level Inverter
PublicationThis paper deals with the selective harmonic elimination pulse width modulation (SHE-PWM) technique. This technique is used for the elimination of selected dominant low order harmonics in the multi-level inverter output voltage. The presence of these harmonics is the essential drawback of such kind of inverters; especially when it is used for the control of different AC drivers. The SHE-PWM is based...
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A CMRC-based compact rat-race coupler with harmonic suppression
PublicationIn this paper, an eective miniaturization technique exploiting compact microstrip resonant cells has been discussed and experimentally validated on the basis of a 3-dB microstrip rat-race coupler. The application of the method proposed has resulted in 91 % circuit area reduction in comparison to a conventional rat-race coupler. Experimental results show good agreement with theoretical characteristics, as well as an additional eect,...