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Wyniki wyszukiwania dla: CONJUGATED LINOLEIC ACID
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The synthesis and structure of a potential immunosuppressant: N-mycophenoyl malonic acid dimethyl ester
PublikacjaThe synthesis of a potential immunosuppressant, i.e. dimethyl ester of N-mycophenoyl malonic acid was optimized in the reaction of mycophenolic acid (MPA) with amino malonic dimethyl ester in the presence of propanephosphonic anhydride (T3P) as a coupling reagent. The structural properties of the obtained MPA derivative were investigated by NMR, MS and single crystal X-ray diffraction methods. Theoretical considerations of conformational...
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Thermal energy storage using stearic acid as PCM material
PublikacjaThis work presents an experimental study of thermal energy storage by use of PCM. The aim of the study was to establish the influence of different inlet temperature of heat transfer fluid (HTF) and different Reynolds number of HTF on intensity of charging process. The PCM used in this study was stearic acid and water was used as HTF. A copper helical coil mounted in cylindrical container served as a heat transfer surface.
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Collagen and hyaluronic acid hydrogel in water-in-oil microemulsion delivery systems
PublikacjaThe efficacy of microemul-sion in dermal and transdermal delivery of active ingredients. Here, we assessed the water-in-oilmicroemulsion capacity to incorporate two natural polymers, i.e. collagen and hyaluronic acid withlow and high molecular weight. Systems were extensively characterized in terms of conductivity, phaseinversion studies, droplet diameter, polydispersity index and rheological properties. The results of thisresearch...
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Photoresponsive, amide-based derivative of embonic acid for anion recognition
PublikacjaThe synthesis and ion-binding properties of amide-based derivative of embonic acid andp-aminoazobenzenewere described. The new compound was characterized by X-ray structural analysis and spectroscopic methods.Ligand interacts in acetonitrile with Y-shaped anions (benzoates and acetates) and dihydrogen phosphatesforming complexes of 1:1 stoichiometry. In more polar DMSO the complexes stoichiometry changes to 2:1(L:anion). Light-inducedtranstocisisomerization...
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Electron-impact ionization cross section of formic acid
PublikacjaExperimental 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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Investigations on the immunosuppressive activity of derivatives of mycophenolic acid in immature dendritic cell
PublikacjaThe main activity of mycophenolic acid (MPA) and its analogs is the inhibition of proliferation of T cells. Here, we hypothesized that MPA and its conjugates inhibits also the activity of antigen-presenting cells (APC) including dendritic cells (DCs). We tested the effect of novel amino acid derivatives of MPA and conjugates of MPA with acridines/acridones on DCs by flow cytometry, ELISA and MLR assay. Both acridines/acridone derivatives...
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Characterization of fatty acid composition in Eurasian badger (Meles meles)
PublikacjaPolyunsaturated fatty acids (PUFAs, LA and ALA) are not synthesized in mammals in the absence of their essential fatty acid precursors. However, hibernating animals and animals sleeping through the winter need sufficiently high amounts of these acids. The Eurasian badger does not hibernate, but sleeps over winter. In the autumn the body weight of adult badgers increases even twofold, since they put on fat before the winter. Fat...
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Novel amides of mycophenolic acid and some heterocyclic derivatives as immunosuppressive agents
PublikacjaThe group of new amide derivatives of mycophenolic acid (MPA) and selected heterocyclic amines was synthesised as potential immunosuppressive agents functioning as inosine-5'-monophosphate dehydrogenase (IMPDH) uncompetitive inhibitors. The synthesis employed uronium-type activating system (TBTU/HOBt/DIPEA) while or phosphonic acid anhydride method (T3P/Py) facilitating amides to be obtained in moderate to excellent yields without...
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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
PublikacjaDerivatization 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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Experimental investigation on heat pipes supported by soy wax and lauric acid for electronics cooling
PublikacjaThis paper presents an experimental study of heat pipes for electronics cooling that were supported by energy storage materials (i.e. phase change materials - PCMs) coated at the adiabatic section. The PCMs utilized included two materials, namely lauric acid and soy wax, the latter being considered as a more cost-effective alternative. The study focused on three different powers: 20 W, 25 W, and 30 W. Both heating, cooling, and...
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The mechanical properties and bactericidal degradation effectiveness of tannic acid-based thin films for wound care
PublikacjaThe surface area is the most important aspect when considering the interactions between a material and the surrounding environment. Chitosan (CTS) and tannic acid (TA) were previously successfully tested by us to obtain thin films to serve as wound dressings or food packaging materials. However, surface properties as well as the antimicrobial activity of the material were not considered. They are important if the material is likely...
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Dissociation of furan-2-carboxylic acid by low energy electrons
PublikacjaElectron attachment to molecular target can lead to a variety of negative fragment ions. We experi- mentally probe the main dissociative electron attachment channels in furan-2-carboxylic acid (C3H3O2 − COOH) - a molecular target composed of two important structural units: a furan ring and a carboxylic group. In our studies we utilise nearly mono-energetic electrons at electron energies from 0 eV up to 15 eV. Our detection setup...
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Dissociative electron attachment and anion-induced dimerization in pyruvic acid
PublikacjaWe report partial cross sections for the dissociative electron attachment to pyruvic acid. A rich fragmentation dynamics is observed. Electronic structure calculations facilitate the identification of complex rearrangement reactions that occur during the dissociation. Furthermore, a number of fragment anions produced at electron energies close to 0 eV are observed, that cannot originate from single electron-molecule collisions....
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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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Chromogenic amides of pyridine-2,6-dicarboxylic acid as anion receptors
PublikacjaThe 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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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 and antiproliferative activity of new mycophenolic acid conjugates with adenosine derivatives
PublikacjaNew conjugates of mycophenolic acid (MPA) and adenosine derivatives were synthesized and assessed as potential immunosuppressants on Jurkat cell line and peripheral blood mononuclear cells (PBMC) from healthy donors. As compared to MPA, all compounds were found to be more active against Jurkat cell line. The antiproliferative activities were compared with MPA and adenosine, in both 2′,3′-O-isopropylidene protected and free hydroxyl...
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Investigation of corrosion behavior of 6060 and 6082 aluminum alloys under simulated acid rain conditions
PublikacjaInstantaneous impedance changes of 6060 and 6082 type aluminum alloys in pure water, and simulated acid rain poured into the pure water was investigated by dynamic electrochemical impedance spectroscopy (DEIS). In this way, the influence of aluminum content on the corrosion behavior of 6060 and 6082 type aluminum alloys immersed in simulated acid rain was determined. The corrosion rate of the alloy decreased with increasing Al...
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Surface Site Modulations by Conjugated Organic Molecules To Enhance Visible Light Activity of ZnO Nanostructures in Photocatalytic Water Splitting
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The physicochemical properties of 3D materials based on hyaluronic acid modified by tannic acid addition
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Influence of the Type of Amino Acid on the Permeability and Properties of Ibuprofenates of Isopropyl Amino Acid Esters
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On the origin of surfaces-dependent growth of benzoic acid crystal inferred through the droplet evaporation method
PublikacjaCrystal growth behavior of benzoic acid crystals on different surfaces was examined. The performed experiments documented the existence of very strong influence introduced by polar surfaces as glass, gelatin, and polyvinyl alcohol (PVA) on the growth of benzoic acid crystals. These surfaces impose strong orientation effect resulting in a dramatic reduction of number of faces seen with x-ray powder diffractions (XPRD). However,...
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On the origin of surfaces-dependent growth of benzoic acid crystal inferred through the droplet evaporation method
PublikacjaCrystal growth behavior of benzoic acid crystals on different surfaces was examined. The performed experiments documented the existence of very strong influence introduced by polar surfaces as glass, gelatin, and polyvinyl alcohol (PVA) on the growth of benzoic acid crystals. These surfaces impose strong orientation effect resulting in a dramatic reduction of number of faces seen with x-ray powder diffractions (XPRD). However,...
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On the origin of surfaces-dependent growth of benzoic acid crystal inferred through the droplet evaporation method
PublikacjaCrystal growth behavior of benzoic acid crystals on different surfaces was examined. The performed experiments documented the existence of very strong influence introduced by polar surfaces as glass, gelatin, and polyvinyl alcohol (PVA) on the growth of benzoic acid crystals. These surfaces impose strong orientation effect resulting in a dramatic reduction of number of faces seen with x-ray powder diffractions (XPRD). However,...
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Poly-L-Lysine-modified boron-doped diamond electrodes for the amperometric detection of nucleic acid bases
PublikacjaBoron-doped diamond (BDD) is a very promising supporting material used in the construction of biosensors for molecular recognition. The direct immobilization of structurally-organized huge molecules, such as poly-L-Lysine (PLL) provides the possibility of determining organic molecules, e.g. nucleic acid bases (e.g. adenine, guanine) or peptides and proteins. This paper describes the direct method for chemical and electrochemical...
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Transdermal transport of collagen and hyaluronic acid using water in oil microemulsion
PublikacjaCollagen and hyaluronic acid (HA) are biopolymers that affect the appearance and condition of the skin. Delivery of these compounds into the skin is highly challenging since have a number of disadvantageous properties, such as high molecular weight and hydrophilicity. Here, we evaluated the transdermal penetration of low and high molecular weight collagen and HA from microemulsions. A number of microemulsion formulations, differing...
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Deep Eutectic Solvents or Eutectic Mixtures? Characterization of Tetrabutylammonium Bromide and Nonanoic Acid Mixtures
PublikacjaDeep eutectic solvents have quickly attracted the attention of researchers because they better meet the requirements of green chemistry and thus have the potential to replace conventional hazardous organic solvents in some areas. To better understand the nature of these mixtures, as well as expand the possibilities of their use in different industries, a detailed examination of their physical properties, such as density, viscosity,...
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Synthesis and characterization of cycloaliphatic hydrophilic polyurethanes, modified with l-ascorbic acid, as materials for soft tissue regeneration
PublikacjaIn this paper we described synthesis and characteristic of obtained hydrophilic polyurethanes (PURs) modified with ascorbic acid (commonly known as vitamin C). Such materials may find an application in the biomedical field, for example in the regenerative medicine of soft tissues, according to ascorbic acid wide influence on tissue regeneration Flora (2009), Szymańska-Pasternak et al. (2011), Taikarimi and Ibrahim (2011), Myrvik...
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The Role of Molecular Structure in Monte Carlo Simulations of the Secondary Electron Yield and Backscattering Coefficient from Methacrylic Acid
PublikacjaIn 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 the addition of citric acid on the physico-chemical properties of poly(sorbitol sebacate-co- butylene sebacate)
PublikacjaThe article presents the results of the physicochemical properties of poly(sorbitol sebacate- co-butylene sebacate) (PSBS) obtained with 0.25; 0.5; 0.75; 1 mol of citric acid (KC). It was shown that PSBS obtained with 0.25 and 0.5 mol KC is characterized by the most optimal mechanical and thermal properties. As a result of the study, it was found that the use of sorbitol and citric acid allows obtaining ester materials with...
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Quantum and carbon dots conjugated molecularly imprinted polymers as advanced nanomaterials for selective recognition of analytes in environmental, food and biomedical applications
PublikacjaSamples with complex matrix analyzed during explanation of pathogenesis of various diseases and food or environmental monitoring request advanced analytical and instrumental devices. Among the materials used for described purposes, quantum (QDs) or carbon dots (CDs) layered by molecularly imprinted polymer (MIP) shells have gained widespread attention. Unique optical and physicochemical properties of QDs/CDs together with high...
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Acid-aided epoxy-amine curing reaction as reflected in epoxy/Fe3O4 nanocomposites: Chemistry, mechanism, and fracture behavior
PublikacjaThis work seeks to answer the question whether or not the presence of acid functional groups accelerate epoxyamine curing reaction. Epoxy/Fe3O4 nanocomposite was considered as a case, where discussions are based on chemistry, mechanism behind curing reactions and fracture behavior influenced by acid assistance to crosslinking. Fe3O4 magnetic nanoparticles (MNPs) with nanosilica decorative layer (B-MNP) were synthesized and subsequently...
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Total cross section for low-energy electron scattering from formic acid, (HCOOH), molecules
PublikacjaTotal cross section (TCS) for low-energy electron scattering from formic acid molecules has been measured using electrostatic electron spectrometer working in linear transmission mode. Two local maxima centered around 1.7 eV and 7.8 eV have been observed and associated with resonant scattering processes.
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Extraction pathways and purification strategies towards carminic acid as natural-based food colorant: A comprehensive review
PublikacjaAs a current trend of fabricating healthier products, food manufacturing companies seek for natural-based food colorant aiming to replace the synthetic ones, which apart from meeting sensorial and organoleptic aspects, they can also act as health promoters offering additional added value. Carminic acid is a natural based food colorant typically found in several insect taxa. However, there are current approaches which pursue the...
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Surface active fatty acid ILs: Influence of the hydrophobic tail and/or theimidazolium hydroxyl functionalization on aggregates formation
PublikacjaNine structurally-related fatty acid ionic liquids have been prepared and their thermal behavior as well as their ability to self-assemble in water has been investigated. The thermal properties were studied by thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC), while the aggregation behavior was analyzed by tensiometry, isothermal titration calorimetry (ITC), conductometry, dynamic light scattering (DLS),...
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Hydroperoxyl radical and formic acid formation from common DNA stabilizers upon low energy electron attachment
Publikacja2-Amino-2-(hydroxymethyl)-1,3-propanediol (TRIS) and ethylenediaminetetraacetic acid (EDTA) are key components of biological buffers and are frequently used as DNA stabilizers in irradiation studies. Such surface or liquid phase studies are done with the aim to understand the fundamental mechanisms of DNA radiation damage and to improve cancer radiotherapy. When ionizing radiation is used, abundant secondary electrons are formed...
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Evaluation of citric acid corrosion inhibition efficiency and passivation kinetics for aluminium alloys in alkaline media by means of dynamic impedance monitoring
PublikacjaA novel approach is proposed for constructing the adsorption isotherm in corrosion studies, based on a well-known interaction between citric acid and aluminium in alkaline electrolytes. Our approach utilizes the instantaneous impedance measurements via Dynamic Electrochemical Impedance Spectroscopy in galvanostatic mode (g-DEIS). Unlike other common tools, g-DEIS delivers exact information about the concentration required for full...
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Feasibility Study of Biohydrogen Production from Acid Cheese Whey via Lactate-Driven Dark Fermentation
PublikacjaThe high loading of lactic acid bacteria (LAB) present in cheese whey still limits its use as hydrogen feedstock. This study aims to investigate the feasibility of producing hydrogen from acid cheese whey via lactate-driven dark fermentation (LD-DF). Mesophilic batch fermentations were performed with delipidated acid cheese whey at a fixed pH of 5.8 and driven by an acidogenic bacterial culture containing LAB and lactate-oxidizing...
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Acid Rider. Idea „komunizmu kwasowego” Marka Fishera a doświadczenie zewnętrzności
PublikacjaAcid communism pozostaje intrygującym wstępem Marka Fishera do planowanej przezeń historycznej rekonstrukcji radykalnych projektów politycznych wyrosłych na gruncie kultury psychodelicznej. Idea ta nie narodziła się w próżni, lecz stanowi konsekwencję jego poszukiwań teoretycznych. Artykuł próbuje osadzić koncepcję „komunizmu kwasowego” w szerszym kontekście, skupiając się na refleksji poświęconej doświadczeniu psychodelicznemu...
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Preliminary Investigation on Rapid Potassium Efflux from Activated Sludge in Response to Use of Peroxyacetic Acid
PublikacjaPreliminary research on activated sludge potassium efflux (GGKE - glutathione-gated potassium efflux) as a result of peroxyacetic acid (PAA) dosing were performed. Similarily as in case of chlorine dosing the PAA dosing causes initiation of bacteria defense mechanisms, related to the transformations of glutathione tripeptide, resulting in the increase of potassium ions concentration in the activated sludge environment. In the range...
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Structural Analysis of 3,5-Bistrifluoromethylhydrocinnamic Acid
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Updates in the Metabolism of Lactic Acid Bacteria
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Amino acid formation by electron irradiation
PublikacjaW artykule zaprezentowano procedurę badania reakcji indukowanych przez niskoenergetyczne elektrony w mieszanych warstwach molekularnych CH3COOD:NH3.
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Synthesis and biological activity of ester derivatives of mycophenolic acid and acridines/acridones as potential immunosuppressive agents
PublikacjaImproved derivatives of mycophenolic acid (MPA) are necessary to reduce the frequency of adverse effects, this drug exerts in treated patients. In this study, MPA was coupled with N-(x-hydroxyalkyl)-9-acridone-4-carboxamides or N-(x-hydroxyalkyl)acridine-4-carboxamides to give respective ester conjugates upon Yamaguchi protocol. This esterification required protection of phenol group in MPA. Designed conjugates revealed higher...
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Ultrashort Cationic Lipopeptides–Effect of N-Terminal Amino Acid and Fatty Acid Type on Antimicrobial Activity and Hemolysis
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Elicitation of solid callus cultures of Salvia miltiorrhiza Bunge with salicylic acid and a synthetic auxin (1-naphthaleneacetic acid)
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Equilibrium and kinetic studies on acid dye Acid Red 88 adsorption by magnetic ZnFe2O4 spinel ferrite nanoparticles
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Mass Spectrometric Identification of 13C-Labeled Metabolites DuringAnaerobic Propanoic Acid Oxidation
PublikacjaBiowaste digestion is a possibility to gain biogas as a renewable fuel source. However, the anaerobic food chain may be disrupted by, e.g., substrate overload or by inhibitors, leading to the accumulation of volatile fatty acids (VFAs), predominantly of propanoic acid (PA). VFA Accumulation may cause a rapid pH decrease, less biogas production, or even a total inhibition. To maintain high biogas productivity or to prevent a collapse...
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The Effect of C45 Carbon Black-Phosphomolybdic Acid Nanocomposite on Hydrogenation and Corrosion Resistance of La2Ni9Co Hydrogen Storage Alloy
PublikacjaIn this paper, we analysed the influence of corrosion processes and the addition of a carbon black-heteropoly phosphomolybdic acid (C45-MPA) nanocomposite on the operating parameters of a hydride electrode obtained on the basis of the intermetallic compound La2Ni9Co. The electrochemical properties of negative electrodes for NiMH batteries were studied using galvanostatic charge/discharge curves, the potentiostatic method, and electrochemical...
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Constituents of Propolis: Chrysin, Caffeic Acid, p-Coumaric Acid, and Ferulic Acid Induce PRODH/POX-Dependent Apoptosis in Human Tongue Squamous Cell Carcinoma Cell (CAL-27)
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