Search results for "Oleum"
showing 10 items of 150 documents
Free radical scavenging capability, antioxidant activity and chemical constituents of Pyrola incarnata Fisch. leaves
2013
Abstract In the present study, the crude extract and its four fractions of petroleum ether, ethyl acetate, n-butanol, water from Pyrola incarnata Fisch. leaves were prepared and their antioxidant activities were investigated by using four antioxidant assays in vitro. The ethyl acetate fraction showed remarkably strong antioxidant activities on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, ABTS radical scavenging, reducing power and β-carotene-linoleic acid bleaching, which were almost comparable to capacities of the positive controls (VC and BHT). The ethyl acetate fraction had the highest total phenolic and total flavonoid contents. Furthermore, Pearson correlation analysis was …
Natural gas hydrates vs. induced dysfunctions in the hydrocarbon extraction process
2021
Cantoned fluids in porous-permeable or fractured media of reservoirs have acquired during the geological time special properties. The fluids from the reservoir could be or not a mixture of reservoir water, liquid hydrocarbons and gaseous hydrocarbons. Considering if inside of a reservoir there are two types of substances like natural gas and reservoir water which may be in the form of vaporous than the condition of saturation of gases with water vaporous is fulfilled. This process is taking place due to thermodynamic equilibrium resulting the so-called gas humidity. This state corroborated with a certain chemical composition plus favourable values of pressure and temperature may be decisive…
Modified photobehavior of carboxylic acid derivatives induced by protonation
1987
Abstract A series of carboxylic acid derivatives 1–6 containing a second interacting function have been converted into the corresponding O -protonated species or acylium ions upon treatment with 96% sulfuric acid or oleum, respectively, at room temperature. The resulting stable cations have been spectroscopically characterized and submitted to irradiation. Cis-trans photoisomerization was observed in the ionic speciesderived from trans -crotonic, fumaric and maleic acids, and maleic anhydride. By contrast protonated crotonolactone 5a+ was found to be photostable. Finally, protonated α-bromobutyrolactone 6a+ was clean and efficiently dehydrohalogenated to 5a+ upon irradiation. Since the norm…
ChemInform Abstract: Modified Photobehavior of Carboxylic Acid Derivatives Induced by Protonation.
1987
Abstract A series of carboxylic acid derivatives 1–6 containing a second interacting function have been converted into the corresponding O -protonated species or acylium ions upon treatment with 96% sulfuric acid or oleum, respectively, at room temperature. The resulting stable cations have been spectroscopically characterized and submitted to irradiation. Cis-trans photoisomerization was observed in the ionic speciesderived from trans -crotonic, fumaric and maleic acids, and maleic anhydride. By contrast protonated crotonolactone 5a+ was found to be photostable. Finally, protonated α-bromobutyrolactone 6a+ was clean and efficiently dehydrohalogenated to 5a+ upon irradiation. Since the norm…
Volatility transmission in the CO<inf>2</inf> and energy markets
2009
The main consequence of the launch, in 2005, of the European Union Emission Trading Scheme (EU ETS) has been the establishment of a price for carbon emissions. Thus, major energy producers in Europe are now aware of the impact of their polluting activities. The interest in analysing the carbon markets from a financial point of view has exponentially increased since the launch of the EU ETS. However, no research articles have focused their attention on the volatility transmission between CO 2 and energy markets. The aim of this paper is to fill this gap in the literature. Specifically, our particular interest is to examine whether or not conditional volatility is transmitted across those mar…
The Acceptable Alternative Vehicle Fuel Price
2019
Historically, petroleum fuels have been the dominant fuel used for land transport. However, the growing need for sustainable national economics has urged us to incorporate more economical and ecological alternative vehicle fuels. The advantages and disadvantages of them complicate the decision-making process and compel us to develop adequate mathematical methods. Alternative fuel (compressed natural gas, liquefied petroleum gas, and ethanol fuel mixtures), the standard prices and their ratios were investigated. A mathematical model to determine a critical ratio between alternative and conventional fuel prices had already been developed. The results of this were investigated. The results sho…
Modernizando la nación : Democracia y autoritarismo en el comité fílmico de la industria petrolera (Venezuela, 1947-1951)
2020
Tras la reforma petrolera de 1943, las compañías petroleras transnacionales con intereses en Venezuela se alinearon con el nacionalismo moderado de las nuevas élites gobernantes y se presentaron como indispensables para el progreso de la nación. Para esto, establecieron departamentos de relaciones públicas, programas de responsabilidad social y de mecenazgo cultural (Tinker Salas, 2009). En este contexto, también crearon programas fílmicos destinados a su fuerza laboral y al público venezolano. El primero de estos programas fue el Comité Fílmico de la Industria Petrolera (1947-1951). Enfocando este programa fílmico desde la categoría cine empresarial, propuesta por Hediger y Vonderau (2009a…
Isolation, characterization and determination of biotechnological potential of oil-degrading bacteria from Algerian centre coast
2019
Aims The Algerian coastline is exposed to several types of pollution, including hydrocarbons. The aim of this work was to isolate oil-degrading bacteria and to explore the intrinsic bioremediation potential of part of its contaminated harbour. Methods and results A collection of 119 strains, capable to grow on mineral medium supplemented with hydrocarbons, were obtained from polluted sediment and seawater collected from Sidi Fredj harbour (Algiers). Twenty-three strains were selected for further studies. Sequencing of the 16S rRNA gene showed that most isolates belong to genera of hydrocarbonoclastic bacteria (Alcanivorax), generalist hydrocarbons degraders (Marinobacter, Pseudomonas, Gordo…
Influence of bioremediation stimulators in soil on development of oat seedlings (Avena sativa) and their aminopeptidase activity / Wpływ pozostałości…
2015
Abstract The selection of bioremediation techniques is important for purification of contaminated soil for agricultural use. Studies on soil contaminated with petroleum substances have indicated that the applied method of remediation has a bigger impact on the development of oat seedlings than the level of contamination. A yeast inoculum appeared to be a technique which was the friendliest to vegetation of oat
Digital solutions transform the forest-based bioeconomy into a digital platform industry : a suggestion for a disruptive business model in the digita…
2018
With the notion that the transformation of the forest-based bioeconomy in recent years provides insightful suggestions not only on the bioeconomy, but on business innovation, this paper conducts an empirical analysis of the transformation and attempts to extract suggestions for a digital-solution-driven, disruptive business model in the digital economy. Notwithstanding the potential broad cross-sectoral benefits, the natural environment, locality constraints, and incessant challenge of distance have impeded the balanced development of the bioeconomy. However, driven by digital solutions, the bioeconomy has taken big steps forward in recent years. Digitalization has enabled real-time, end-to…