1,216 research outputs found

    Negative electrode catalyst for the iron chromium redox energy storage system

    Get PDF
    A redox cell which operates at elevated temperatures and which utilizes the same two metal couples in each of the two reactant fluids is disclosed. Each fluid includes a bismuth salt and may also include a lead salt. A low cost, cation permselective membrane separates the reactant fluids

    Bismuth nitrate-induced microwave-assisted expeditious synthesis of vanillin from curcumin

    Get PDF
    Background: Curcumin and vanillin are the two useful compounds in food and medicine. Bismuth nitrate pentahydrate is an economical and ecofriendly reagent. Method: Bismuth nitrate pentahydrate impregnated montmorillonite KSF clay and curcumin were subjected to microwave irradiation. Results: Microwave-induced bismuth nitrate-promoted synthesis of vanillin from curcumin has been accomplished in good yield under solvent-free condition. Twenty-five different reaction conditions have been studied to optimize the process. Conclusion: The present procedure for the synthesis of vanillin may find useful application in the area of industrial process development

    An attempt to obtain Bi_{4}Ti_{3}O_{12}-PVC textured ceramics-polymer composites

    Full text link
    Bi_{4}Ti_{3}O_{12}-PVC composites were fabricated. Ceramics powders of bismuth titanate were prepared by the sol-gel method using bismuth nitrate pentahydrate Bi(NO_{3})_{3} \cdot 5H_{2}O and tetrabutyl titanate Ti(CH_{3}(CH_{2})_{3}O)_{4} as precursors. The Bi_{4}Ti_{3}O_{12}-PVC composites were fabricated from ceramics powders and polymer powders by hot-pressing method.Comment: 4 pages, 4 figure

    Bismuth nitrate pentahydrate-induced novel nitration of eugenol

    Get PDF
    Background: Eugenol, the main constituent of clove oil possesses a number of medicinal activities. To enhance the medicinal property, structural modification is required. On the other hand, bismuth nitrate pentahydrate has been established as an excellent eco-friendly nitrating agent for several classes of organic compounds. Results: Bismuth nitrate pentahydrate-induced nitration of eugenol has been investigated very thoroughly. Twenty five different conditions have been studied. The microwave-induced solvent-free reaction has been identified as the best condition. Conclusions: Spectral analyses confirm that 5-nitroeugenol is the sole product in all the cases. No oxidized or isomerized product could be detected

    A Microwave-Assisted Bismuth Nitrate-Catalyzed Unique Route Toward 1,4-Dihydropyridines

    Get PDF
    The classical Hantzsch reaction is one of the simplest and most economical methods for the synthesis of biologically important and pharmacologically useful 1,4-dihydropyridine derivatives. Bismuth nitrate pentahydrate under microwave irradiation is proven to act as a very efficient catalyst for a one-pot, three-component synthesis of 1,4-dihydropyridines in excellent yields from diverse amines/ammonium acetate, aldehydes and 1,3-dicarbonyl compounds within 1-3 min under solvent-free conditions. The present environmentally benign procedure for the synthesis of 1,4-dihydropyridines is suitable for library synthesis and it will find application in the synthesis of potent biologically active molecules. The excellent yield and extreme rapidity of the method is due to a concurrent effect of the catalyst and microwave irradiation

    Towards improvement of bismuth and tellurium as a thermoelectric material for energy harvesting through nanostructuring

    No full text
    It has been demonstrated that lyotropic liquid crystal templates (LLCT) with mesoporous structures can be used during electrodeposition of thin films to produce films with a mesoporous structure transferred from the LLCT. Here we report the electrodeposition of mesoporous bismuth telluride (Bi2Te3) films from hexagonal structured LLCTs formed from mixtures of Brij®C10 and electrolyte solution in ratios of (55:45, 50:50, 45:55). The introduction of a mesoporous nanostructure to the bismuth telluride films should improve the thermoelectric properties of the material. Optimisation of the electrolyte solutions has been carried out, studying the effects of using the metals bismuth (Bi) and tellurium (Te) and the metal salts bismuth citrate (C6H5BiO7), bismuth nitrate pentahydrate (Bi(NO3)3·5H2O and tellurium dioxide (TeO2) dissolved in nitric acid (HNO3) or citric acid (C6H8O7) in different ratios and concentrations. The addition of a buffer solution made of citric acid and sodium citrate (C6H5Na3O7) has also been investigated. The lyotropic liquid crystal phases present for mixtures containing different concentrations of Brij®C10 and these electrolyte solutions has been looked at, including the production of phase diagrams. The liquid crystal template mixtures have been characterised using a polarised optical microscope (POM) and wide and small angle X-ray Diffraction (XRD) and Cyclic Voltammetry (CV). The deposited thin films have been characterised using wide and small angle XRD, Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray spectroscopy (EDX), confirming that hexagonally nanostructured thin films in the (110) orientation with a composition close to Bi2Te3 have been produced

    EXPEDITIOUS GREEN SYNTHESIS OF VERSATILE ORGANIC COMPOUNDS BY DIVERSE METHODS

    Get PDF
    Synthesis of organic compounds requires organic solvents and reagents to promote them. Very often, toxic solvents are used for this purpose. Many organic reactions require molar proportion of reactants and reagents to accomplish the goal. Some reactions require longer reaction times and produce products without control of stereochemistry. Therefore, development of facile and effective organic reactions under environmentally friendly conditions is necessary. In this perspective, several reactions are discussed that are performed by microwave-induced reactions, catalytic procedures, in the absence of any solvents, one-pot method and in water. Important reactions are chosen to investigate the feasibility of conducting these reactions under green chemistry conditions

    Catalyst free, base free microwave irradiated synthesis of aryl nitrites from potassium aryltrifluoroborates and bismuth nitrate

    Get PDF
    A mixture of bismuth nitrate pentahydrate and potassium aryltrifluoroborate in toluene under microwave heating at 120°C for 20min provides an interesting and mild reaction protocol for the synthesis of aryl nitrite. The conversion to aryl nitrites from aryltrifluoroborates without transition metal catalyst and base in high yields is remarkable

    A Highly Efficient Bismuth Salts-Catalyzed Route for the Synthesis of Alpha-Aminophosphonates

    Get PDF
    A convenient synthesis of different types of α-amino phosphonates via one-pot solvent-free three component reactions of aldehydes, amines and phosphites catalyzed by bismuth salts has been investigated. Bismuth triflate is found to be the most effective catalyst for this reaction

    SYTHESIS OF GLUCOSE PERACETATE VIA BISMUTH NITRATE-INDUCED REACTION

    Get PDF
    Simple synthesis peracetylated glucose has been achieved starting from glucose and acetic anhydride in the absence of solvent via bismuth nitrate-catalyzed reaction. This method does not need large excess of acetic anhydride
    corecore