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Search results for: SOL–GEL SYNTHESIS
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Hydrothermal synthesis of vanadium ammonium compounds – the crucial role of the pressure
PublicationDue to the structural diversity and chemical activity, vanadium oxides and their derivatives are continuingly in the great interest of scientist. In a large family of vanadium compounds, one of the most interesting are ammonium vanadates (with the general formula (NH4)xVyOz). They have received much attention because of their promising application as cathode material in mono- and multivalent-ion batteries [1]. Hydrothermal synthesis...
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An Improved Synthesis of Trisodium (R)-Homocitrate from Citric Acid
PublicationA method of synthesis of trisodium (R)-homocitrate starting from citric acid is reported. The procedure affords the final product of high optical purity with satisfactory yield.
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Virtual keyboard controlled by eye gaze employing speech synthesis
PublicationThe article presents the speech synthesis integrated into the eye gaze tracking system. This approach can significantly improve the quality of life of physically disabled people who are unable to communicate. The virtual keyboard (QWERTY) is an interface which allows for entering the text for the speech synthesizer. First, this article describes a methodology of determining the fixation point on a computer screen. Then it presents...
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Virtual Keyboard controlled by eye gaze employing speech synthesis
PublicationThe article presents the speech synthesis integrated into the eye gaze tracking system. This approach can significantly improve the quality of life of physically disabled people who are unable to communicate. The virtual keyboard (QWERTY) is an interface which allows for entering the text for the speech synthesizer. First, this article describes a methodology of determining the fixation point on a computer screen. Then it presents...
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AGREEMIP: The Analytical Greenness Assessment Tool for Molecularly Imprinted Polymers Synthesis
PublicationMolecular imprinting technology is well established in areas where a high selectivity is required, such as catalysis, sensing, and separations/sample preparation. However, according to the Principles of Green Chemistry, it is evident that the various steps required to obtain molecularly imprinted polymers (MIPs) are far from ideal. In this regard, greener alternatives to the synthesis of MIPs have been proposed in recent years....
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A Novel Synthesis Technique for Microwave Bandpass Filters with Frequency-Dependent Couplings
PublicationThis paper presents a novel synthesis technique for microwave bandpass filters with frequency-dependent couplings. The proposed method is based on the systematic extraction of a dispersive coupling coefficient using an optimization technique based on the zeros and poles of scattering parameters representing two coupled resonators.The application of this method of synthesis is illustrated using two examples involving four and five-pole...
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Synthesis and Properties of the Ba2PrWO6 Double Perovskite
PublicationWe report details on the synthesis and properties of barium praseodymium tungstate, Ba2PrWO6, a double perovskite that has not been synthesized before. Room-temperature (RT) powder X-ray diffraction identified the most probable space group (SG) as monoclinic I2/m, but it was only slightly distorted from the cubic structure. X-ray photoelectron spectroscopy confirmed that the initial (postsynthesis) material contained praseodymium...
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Synthesis of amides under microwave irradiation
PublicationAmides belong to the most important carboxylic acid derivatives. They are constituents of natural compounds like peptides and proteins. They found applications in many branches of science and industry, especially in pharmaceutical and polymer science. Conventional procedures for amide preparation involve reaction between amine and carboxylic acid or their more active derivatives such as acid chlorides, acid anhydrides or esters....
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Smart Virtual Bass Synthesis Algorithm Based on Music Genre Classification
PublicationThe aim of this paper is to present a novel approach to the Virtual Bass Synthesis (VBS) algorithms applied to portable computers. The proposed algorithm employed automatic music genre recognition to determine the optimum parameters for the synthesis of additional frequencies. The synthesis was carried out using the non-linear device (NLD) and phase vocoder (PV) methods depending on the music excerpt genre. Classification of musical...
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Convenient and efficient synthesis of functionalized unsymmetrical alkynyl sulfides
PublicationWe developed a simple and efficient method for the synthesis of functionalized unsymmetrical alkynyl sulfides under mild conditions in good yields. The designed method is based on the reaction of 5,5-dimethyl-2-thioxo-1,3,2-dioxaphosphorinan-2-disulfanyl derivatives with lithium acetylides. The developed method allows the preparation of unsymmetrical alkynyl sulfides bearing additional hydroxyl, carboxyl, or amino functionalities.
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Thin CVD diamond films - synthesis, properties, applications
PublicationThe basic model of diamond films growth, in the low pressure synthesis, deposition from the CVD gas phase, is the mixture of hydrocarbon gas in presence with activated hydrogen and its nucleation on the substrate as a result of pyrolysis reaction. It allows to cross the great energetic barrier between graphite and diamond. High pressure and temperature are replaced by change of electronic structure of atoms into gas precursors...
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An Approach to Bass Enhancement in Portable Computers Employing Smart Virtual Bass Synthesis Algorithms
PublicationThe aim of this paper is to present a novel approach to the Virtual Bass Synthesis (VBS) algorithms applied to portable computers. The developed algorithms are related to intelligent, rule-based setting of synthesis parameters according to music genre of an audio excerpt and to the type of a portable device in use. To find optimum synthesis parameters of the VBS algorithms, subjective listening tests based on a parametric procedure...
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Tailoring the Size and Shape—New Path for Ammonium Metavanadate Synthesis
PublicationAmmonium metavanadate, NH4VO3, plays an important role in the preparation of vanadium oxides and other ammonium compounds, such as NH4V3O8, (NH4)2V3O8, and NH4V4O10, which were found to possess interesting electrochemical properties. In this work, a new route for the synthesis of NH4VO3 is proposed by mixing an organic ammonium salt and V2O5 in a suitable solvent. The one-step procedure is carried out at room temperature. Additionally,...
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Ammonium and potassium vanadates: synthesis, physicochemical characterization, and applications
PublicationThis doctoral thesis is devoted to the synthesis and investigation of ammonium/potassium vanadates, which constitute an interesting group of materials due to their potential applications in electrochemical devices and photocatalysis. The scope of the conducted experimental work included the synthesis of ammonium/potassium vanadates, their physicochemical characterization using various methods (spectroscopy, microscopy, thermal...
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Chemical modifications of natural oils and examples of their usage for polyurethane synthesis
PublicationNatural oils have been used in the production of plastics for a long time. However, the number of studies dedicated to polyurethane research has shown an increase only recently. Usually, petrochemical components are used in polyurethane synthesis. Nowadays, there have been attemptsmade to replace polyols in polyurethanes with the modified oils and other natural raw materials. It is a promising and important scenario because the...
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An efficient and convenient synthesis of unsymmetrical disulfides from thioacetates
PublicationWe have developed convenient methods for the synthesis of functionalized unsymmetrical dialkyl disulfides under mild conditions in very good yields. The designed method is based on the reaction of (5,5-dimethyl-2-thioxo-1,3,2-dioxaphosphorinan-2-yl)-disulfanyl derivatives 1 with functionalized alkyl thiolate anions, generated in situ from thioacetates2and sodium methoxide or butylamine. The developed method allows the preparation...
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Complexes of silanethiolate ligands: Synthesis, structure, properties and application
PublicationThe purposeful syntheses of silanethiolate complexes started approximately in the mid-eighties of the 20th century but no summary of the synthetic efforts has been reported till now. The synthetic methods and the resulting complexes have some common features, which are emphasized throughout the review. Thereby specific difficulties during synthesis are outlined and the structures, properties and possible applications of the resulting...
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Luminescence kinetics in silica gel doped with Tb3+ ions and ZnS:Mn2+ nanocrystals
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Characterization of Modified Silica Gel as a Source of Ethene for Standard Gaseous Mixtures
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Degradation of Gel-Coat Layer in Glass/Polyester Laminate in Seawater Environment
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Initial evaluation of commercial optical CT‐based 3D gel dosimeter
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Image registration of BANG® gel dose maps for quantitative dosimetry verification
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Two-dimensional gel-based serum protein profile of growing piglets
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Preliminary Studies on a Lightweight Porous Cement-Based Composite – Gel Concrete
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Functionalized polyolefins, synthesis application and industrial relevance
PublicationPolymers play a key role in our modern life full of technical advances and a continuous request for new materials with tailored properties for a low price. Their excellent mechanical properties, good processability, chemical stability and low price make polyolefins the polymers of choice for most commodity and some more specialized applications. As a result, polyolefins account for over 65% of the total world demand of plastic...
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Application of multicriteria decision analysis to assess the greenness of molecularly imprinted polymers synthesis components
PublicationThe study applies multicriteria decision analysis (MCDA) to rank the components of molecularly imprinted polymers (MIPs) synthesis according to their greenness. The components are taken from papers that are describing synthesis of MIPs for persistent organic pollutants (POPs) sorbents. Functional monomers (n = 14), target/surrogate molecules (n = 10), porogens (n = 8), cross-linking agents (n = 8) and initiators (n = 4) are described...
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Design and synthesis of new analogues of batracylin linked to tuftsin and retro-tuftsin derivatives
PublicationThe synthesis of derivatives of batracylin with several peptides was elaborated followed by their cytotoxic activity investigation.
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Convenient and efficient synthesis of functionalized unsymmetrical Z-alkenyl disulfanes
PublicationWe developed a simple and efficient method for the synthesis of functionalized unsymmetrical Z-alkenyl disulfanes under mild conditions in moderate to good yields. The designed method is based on the reaction of Z-alkenyl thiotosylates with thiols in the presence of base. The developed method allows the preparation of unsymmetrical Z-alkenyl disulfanes bearing additional hydroxy, carboxy, or amino functionalities.
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Noncryogenic Synthesis of Functionalized 2-Methoxypyridines by Halogen-Magnesium Exchange Using Lithium Dibutyl(isopropyl)magnesate(1-) and Lithium Chloride
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Synthesis and properties of new 'N,'N-phenyltetrazole podand
PublicationThe synthesis of a new chromogenic N,N-phenyltetrazole receptor is reported here. The cationbinding properties of this receptor in solution were investigated by naked-eye colour change, electrochemical methods and UV-Vis spectroscopy in various solvents (CH3CN, dimethylsulphoxide (DMSO), DMSO/H2O, CH3CN/H2O and CH3CN/MeOH). In addition, the receptor was used as a sensing material in ion-selective membrane electrodes. The selectivity...
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A Review on Deactivation and Regeneration of Catalysts for Dimethyl Ether Synthesis
Publicationhe deactivation of catalysts and their regeneration are two very important challenges that need to be addressed for many industrial processes. The most quoted reasons for the deterioration of dimethyl ether synthesis (DME) concern the sintering and the hydrothermal leaching of copper particles, their migration to acid sites, the partial formation of copper and zinc hydroxycarbonates, the formation of carbon deposits, and surface...
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Design and synthesis of TiO2/Ti3C2 composites for highly efficient photocatalytic removal of acetaminophen: The relationships between synthesis parameters, physicochemical properties, and photocatalytic activity
PublicationIn this study, we report the potential of TiO2/Ti3C2 composite fabricated by oxidation of MXene for degradation of persistent organic pollutants. The effect of the synthesis conditions (time, temperature, and reaction environment) on the morphology, physicochemical properties, and photocatalytic activity was investigated. It was found that acetaminophen degradation was positively correlated with TiO2 content in the composite structure. Furthermore,...
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Determination of modifier contents in polymer-modified bitumens and in samples collected from the roads using high performance gel permeation/size exclusion chromatography
PublicationThis paper describes application of high performance gel permeation/size exclusion chromatography (HP-GPC/SEC) for the determination of content of polymer modifiers in modified road bitumens. The obtained results were compared with the measurements based on the procedure recommended by the American Association of State Highway and Transportation Officials, which employs Fourier transform mid-infrared spectroscopy (mid-IR FTIR)....
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Synthesis and characterization of novel aliphatic polyurethanes for tissue engineering applications
PublicationSummarizing, in this thesis was described the synthesis of novel PUR system, which was obtained by using aliphatic diisocyanate (HDI), amorphous macrodiol (PEBA) and chain extender (BDO). This PUR system was established as suitable for TE purpose and successfully modified with AA, which as expected improved its biocompatibility. According to this, AA-modified HDI-based PURs is the PUR system ready for further studies including...
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Synthesis of Combretastatin A-4 Analogs and their Biological Activities
PublicationCombretastatin A-4 (CA-4) is a natural product, which consists of two phenyl rings, linked by an ethylene bridge. CA-4, inhibitor of polymerization of tubulin to microtubules, possesses a strong antitumor and anti-vascular properties both in vitro and in vivo. Previous studies showed that disodium phosphate salt of CA-4, a water-soluble prodrug is well tolerated at therapeutically useful doses. However, it should be noted that...
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Developments in the synthesis and biological activity of Glycyl-L-Histydyl-L-Lysine derivatives
PublicationWe emphasize on the methods of the synthesis described in the literature and present the aspects of Gly-His-Lys structure modifications that played a key role in scientific research.
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Micellar Route of the Synthesis of Alkyl Xylosides: An Unexpected Effect of Amphiphilic Imidazolium Ionic Liquids
PublicationThis manuscript presents results from the investigation on the synthesis of alkyl xylosides by the novel, very efficient and promising protocol of the Fischer synthesis from unprotected xylose and aliphatic alcohol. The use of 1-alkyl-3-methylimidazolium hydrogen sulfate ionic liquids as the catalysts with dual functionality (surfactant + acid catalyst) and micellar reaction system are the main novelty of described method. It has...
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Catalysts for advanced oxidation processes: Deep eutectic solvents-assisted synthesis – A review
PublicationNew catalyst synthesis techniques, including green materials, are extensively studied for heterogeneous photocatalytic advanced oxidation processes (AOPs) on spotlight of sustainable development. Deep eutectic solvents (DESs) started to be used in this field as environmentally friendly alternative to ionic liquids (ILs). During the catalyst synthesis, DESs can act as stabilizers, capping agents, structure directing agents, templates,...
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Inhibitors of angiogenesis in cancer therapy – synthesis and biological activity
PublicationAngiogenesis is the process of formation of new capillaries from preexisting blood vessels. Angiogenesis is involved in normal physiological processes, and plays an important role in tumor invasion and development of metastases. Vascular endothelial growth factor (VEGF) plays a key role in angiogenesis. VEGF is a mitogen for vascular endothelial cells and stimulates their proliferation. By inhibiting the biological activity of...
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The new method of ZnIn2S4 synthesis on the titania nanotubes substrate with enhanced stability and photoelectrochemical performance
PublicationThe new method of ZnIn2S4 synthesis on the titania nanotubes substrate with enhanced stability and photoelectrochemical performance
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On the synthesis of coupled-lossy resonator filters with unloaded quality factor control
PublicationA technique for fast synthesis of coupling matrix low-pass prototypes of generalized Chebyshev bandpass filters with lossy resonators is presented in this paper. The coupling matrix is found by solving a nonlinear least squares problem based on zeros and poles of filter's transfer functions. Additional constraints are introduced that allow one to control the level of unloaded quality factor of resonators.
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Synthesis an anglophone journal of comparative literary studies
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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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Nanoparticles: Synthesis, characteristics, and applications in analytical and other sciences
PublicationNanoparticles (NPs) are widely employed in different research areas, ranging from analytical chemistry and environmental science to medicine, the agriculture and pharmaceutical industry. This is mainly due to the unique characteristics of NPs and the novelty they introduce in such applications. In analytical chemistry, the role of NPs can differ depending on the nature of the steps involved in analytical process. NPs are probably...
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Magnetic resonance imaging of radiation dose distributions using a polymer-gel dosimeter
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SU‐GG‐T‐290: A Fast Optical CT Scanner for Gel Dosimetry
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Gel-based separation of single-walled carbon nanotubes for metallic and semiconducting fractions
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Gel glass transition in silica and nitrided silica aerogels experiment and computer modelling.
PublicationPrzedstawiono dane eksperymentalne i symulacje komputerowe metodą dynamiki molekularnej procesu densyfikacji do szkła aerożeli krzemianowych i azotowanych aerożeli krzemianowych.
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Synthesis and properties of carboxy derivative of Epidian 6 monomethacrylate (in English)
PublicationWe present the synthesis of an oligomer with carboxy and methacrylic groups based on Epidian 6. The effect of the catalyst nature and amount, solvent nature and process temperature on the rate of the reaction between Epidian6 monomethacrylate and adipic acid was examined at 313, 323 and 333 K in the presence of 4-dimethylaminopyridine, 1,4-diazobicyclo[2.2.2]octane, and benzyltriammonium chloride. The synthesized oligomer was characterized...
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Beta-Galactosidases of Pseudoalteromonas sp. – Characteristics and application for lactose hydrolysis and galactopyranosides synthesis
PublicationBeta-galactosidase [EC 3.2.1.23] is an enzyme that catalyzes the hydrolysis of O-glycosidic linkages in galactosides. It has biotechnological applications in the dairy industry for the production of milk with a low content of lactose and galactooligosacharides for use in healthy food. The transgalactosylation activity of beta-galactosidase can be used in the synthesis of alkyl galactopyranosides. Due to the fact that conditions of...