34 research outputs found

    Note on the Preparation of Some Thiobarbiturates

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    It has been shown that barbituric acid derivatives can be prepared in good yield by gradually adding sodium methoxide as condensation catalyst to a cyanoacetic or malonic ester reacting with urea or its derivatives. The principle of the gradual addition of sodium methoxide as condensing agent has now been extended to condensations of some substituted cyanoacetic and malonic esters with thiourea

    Note on the Preparation of Some Thiobarbiturates

    Get PDF
    It has been shown that barbituric acid derivatives can be prepared in good yield by gradually adding sodium methoxide as condensation catalyst to a cyanoacetic or malonic ester reacting with urea or its derivatives. The principle of the gradual addition of sodium methoxide as condensing agent has now been extended to condensations of some substituted cyanoacetic and malonic esters with thiourea

    Preparation of Some lmino- and Cyano-imino-substituted Barbiturates

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    A number of imino- and cyano-iminobarbituric acid derivatives has been prepared in good yield by gradually adding sodium methoxide - as condensation catalyst - to some substituted cyanoacetic and malonic esters reacting with urea, dicyandiamide and guanidine

    Preparation of Some lmino- and Cyano-imino-substituted Barbiturates

    Get PDF
    A number of imino- and cyano-iminobarbituric acid derivatives has been prepared in good yield by gradually adding sodium methoxide - as condensation catalyst - to some substituted cyanoacetic and malonic esters reacting with urea, dicyandiamide and guanidine

    Quality of silage of mixed sunchoke and lucerne forage

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    The paper presents the chemical composition, nutritional and usable value of sunchoke (Helianthus tuberosus L.) and the possibility of using it for animal nutrition in fresh and canned form. Tests show that sunchoke cut in mid-June contains about 9.43% of crude protein, 2.49% of crude fat, 19.93% of crude cellulose, 50.50% of NFE (nitrogen-free extractives) and 17.65% of ash in the dry matter. Although lucerne biomass had a more favorable chemical composition (18.13% crude protein, 6.72% crude fat, 25.24% crude cellulose, 39.35% BEM and 10.56% ash), the benefits of sunchoke are in the more successful growing in less favorable natural, primarily soil conditions, the more suitable it is for ensiling and the longer it stays on one planted plot. Since it is predominantly an energy (carbohydrate) nutrient, the possibility of ensiling the green biomass of sunchoke in a mixture with 25, 50 and 75% fresh lucerne (25% dry matter) was investigated. The obtained results show that with the increase of lucerne participation, the nutritional value of silage increases, but the quality decreases. In addition to its role in conventional feed production, sunchoke can be an important plant in the system of organic production, production for industrial processing and for extensive cultivation in hunting grounds

    Site-selective quantum correlations revealed by magnetic anisotropy in the tetramer system SeCuO3

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    We present the investigation of a monoclinic compound SeCuO3 using x-ray powder diffraction, magnetization, torque and electron-spin-resonance (ESR). Structurally based analysis suggests that SeCuO3 can be considered as a 3D network of tetramers. The values of intra-tetramer exchange interactions are extracted from the temperature dependence of the susceptibility and amount to ~200 K. The inter-tetramer coupling leads to the development of long-range antiferromagnetic order at TN = 8 K. An unusual temperature dependence of the effective g-tensors is observed, accompanied with a rotation of macroscopic magnetic axes. We explain this unique observation as due to site-selective quantum correlations

    Electrodeposition and electroless deposition of metallic powders: A comparison

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    Electrodeposition and electroless deposition of metallic powders were comparatively investigated. Electrodeposition of copper is accompanied with the simultaneous hydrogen evolution, which significantly influences the morphology of Cu powder. At lower overpotentials, branched dendrites were produced. At higher overpotentials honeycomb-like deposits of copper were obtained. Formation of silver powders was characterized by the comparison of the exchange and limiting current densities. Instantaneous growth of dendrites starts at low overpotential due to large exchange current density in silver nitrate solution. Formation of powders such as Ni, Co, Ag, Pd and Au from homogenous solutions using an appropriate reducing agent or via galvanic displacement reaction was demonstrated. The hydrolysis of metallic ions is crucial in the deposition metallic powders via electroless deposition from homogenous solutions. Oxides, such as Ag 2O, Cu 2O and CuO, suspended in water can successfully be reduced with an appropriate reducing agent, leading to the precipitation of metallic powders

    CORRELATION OF MORPHOLOGIC AND PRODUCTION TRAITS OF HONEY BEE COLONIES FROM SERBIA

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    Abstract: State of mutual or reciprocal relationship between traits is determined by the correlation coefficients. Correlation of morphological and production traits was determined in two generations of honey bee colonies. In the first generation, mother queen bees were studied, and in the second generation, their offspring. The study of one generation lasted two years. Morphological traits were determined in the beginning of the study and production traits were determined in the spring and autumn inspections of every year. In the first generation, the positive and mostly high correlation between morphological traits, and honey yield and hygienic behaviour was determined. Correlation of morphological traits, colony strength and food supplies per colony ranged from highly positive to slightly negative values. It was found that there was a high correlation between some production traits (colony strength in the spring and autumn inspections and honey yield per colony). In the analysis of offspring (second generation), most traits that were positively correlated in mother generation now, also, showed a similar relationship. The only difference, in contrast to mother generation, was that, for most traits, the intensity of interaction increased
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