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[en] The present article deals with investigation of gamma - irradiated petrole samples by means of FT-IR spectroscopy. The transformation of irradiated hydrocarbons takes play in the presence of bentonite. It was discovered that after irradiation of crude oil from Gunesli fields with bentonite it takes play isomerization of hydrocarbons.
[en] The equilibrium isotherms of zinc adsorption onto natural bentonite show that the data correlate well with freundlich and Langmuir's models and that the adsorption is physical in nature. The operating parameters (agitation speed, solid/liquid ratio temperature, particle size and initial zinc concentration) influenced the rate of adsorption. The maximum monomolecular capacity (Q0) according to the Langmuir model is 52.91 mg. g-1 for an initial zinc concentration of 300 mg. litre-1, At 200C
[en] The article presents the basic methods of the most effective durable solution for the restoration of underground waterproofing of the structures in use, which are in impossible conditions for the application of outdoor protection. New types of resistance to aggressive environments of mineral waterproofing are considered, along with the technological scheme for the work. In addition, organizational methods have been developed for hydro protection of building structures. This technology can be applied from the basement of buildings in operation and be implemented at any time of the year. The proposed modern materials and technological solutions for the protection of underground structures of buildings were confirmed by the authors using an analysis carried out using the mathematical apparatus. Creating protection of premises against leaks from the mineral composition allows to increase the durability of the building itself, to ensure the normal operation of equipment and monitoring devices of the stations, as well as comfortable conditions for staff. Technological maps for the device of a new type of filling waterproofing have been developed, allowing to carry out and monitor all technological processes for operations. (paper)
[en] Plate shaped bentonite particles of size ∼600 nm and thickness ∼2 nm are dispersed in a magnetic nanofluid. Magnetic field dependent flow behavior of this composite suspension is studied using a horizontal microcapillary placed between the poles of an electromagnet. The plate shaped bentonite particle produces extra hindrance to the flow under the application of moderate magnetic field and produces an enhanced magnetoviscous effect. 75% volume concentration of bentonite produces eight times larger change in magnetic field dependent viscosity than does the pure magnetic nanofluid. Hindrance to the flow is due to the chain like structure of magnetic nanoparticles, tumbling and rotational motion of bentonite particles and interaction between magnetic and bentonite particles. The field-induced structures are also observed using an optical microscope. Results offer several advantages over the inverse MR effect as well as to study the motion of biological cells and tissues under the effect of magnetic field. -- Highlights: ► Dispersed plate shaped bentonite particles in magnetic fluids to study capillary viscosity. ► Increased viscosity is due to the hindrance to the rotation of the bentonite particles. ► Increase in viscosity is five times larger for bentonite particles than the pure magnetic fluids. ► This is a new kind of magnetoviscous effect, dispersing anisotropic particles in magnetic fluids
[en] Increasing the level of ionizing radiation has a negative effect on human life. Compliance with the basic principles determines the safety of the environment in its original form. Taking into account the fact of the wide use of natural aluminosilicates, in particular bentonite clays, in industry and everyday life, it was of scientific and practical interest to study the distribution of radioactive elements in them. A number of bentonite clays selected from various deposits of the Azerbaijan Republic has been analyzed.
[en] After the success of experiments using the Iraqi Bentonite in the work of drilling oil wells as an alternative to the importer Bentonite which encouraged its use as an alternative for the work of civil excavation, such as diaphragm walls, drilling, bore pile, barriers, dams and tunnels. By changing the mixing and drilling method followed in the work of oil wells, which requires the conduct of many experimental mixtures to reach the optimal mix. Benefits were getting from the previous experiments conducted on such type of Bentonite were used by the General Company for Geological Survey and Mining and Ramadan Mubarak Company one of the formalization of the Ministry of Housing and Construction; in which the optimum mix was reached, the method of mixing was determined, the components and quantities of the materials included in the preparation of the optimal mix were determined in 1m3 of water for mixing time of 5 min. This study was supported by the results obtained by the Geological Survey and Mining Company, which relied on the use of (NaOH) as an alternative to the active calcium-centric (CMC) of Bentonite, which is considered to be one of the most expensive materials. This paper will be a good index for all concerned with implementation of civil excavations and field works. (paper)
[en] In this study, modified bentonite was used as man-made barrier systems to investigate occurring reactions with interaction of 79''Se with barrier material systems to protect the environment from radioactive contamination. Thermodynamic parameters of interaction between dominant ion species of selenium and modified bentonite depend on contact time were investigated. In the interaction between modified bentonite and selenium, enthalpy (ΔH), entropy (ΔS) and Gibbs free energy (ΔG) were found to have different behaviours depending on the contact time. The adsorption enthalpy increases the duration of the endothermic reaction to the exothermic reaction one hour after the transition and endothermic reaction occurs after two hours.
[en] The adsorption of Cs on clayey materials such as bentonite and Na-montmorillonite was studied in various electrolytic conditions (concentration and composition), various solid to liquid ratios and various pH conditions. The results obtained for these different conditions were modeled considering an exchange model associated to the surface complexation concept. Then, the same approach was considered to model the sorption of Rb, which have the same chemical behavior than Cs. Experiments were carried out for various electrolyte, pH, and Rb concentrations. The stoichiometries corresponding to the sorption of Rb on bentonite and montmorillonite were then deduced from the experimental results. (author)
[en] Adsorption of uranium contained in industrial phosphoric acid has been carried out by batch. The industrial phosphoric acid and the bentonite have been previously caracterized. Theorical models of Langmuir and Freundlich have been applied to the equilibrium isotherm of uranium adsorption to represent the experimental results
[en] Bentonite has been considered as a candidate buffer material in the underground repository for the disposal of high-level radioactive waste because of its low permeability, high sorption capacity, self sealing characteristics, and durability in nature. The water uptake from the rock and the associated swelling causes a penetration of the bentonite into open fractures, the front of the advancing clay being characteristically very soft. Knowledge of the potential extent of colloid generation is required to estimate the required stability for disposal borehole buffer material and to estimate the potential influence of bentonite colloid on radionuclide transport in deep geological media. It has been recently shown that bentonite colloids can be generated at the host rock/buffer interface of such repositories. Bentonite colloids may constitute an additional mechanism for radionuclide migration toward the geosphere and biosphere, provided they are stable. In this study, therefore, the potential for generation of bentonite colloids caused by the groundwater erosion and the resulting bentonite colloids was studies experimentally for a Korean Ca-bentonite under repository relevant conditions