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•Water disinfection by simultaneous treatment with hydrodynamic cavitation and plasma discharge.•Decomposition of organic pollutants in water under hydrodynamic cavitation and ...plasma.•Easily scalable hybrid technology combining cavitation and plasma.•Intense generation of radicals, UV light, shock waves and charged particles.•Prolonged oxidation takes place in the solution/suspension after the end of the treatment.
Over the last two decades, the scientific community and industry have made huge efforts to develop environmental protection technologies. In particular, the scarcity of drinking water has prompted the investigation of several physico-chemical treatments, and synergistic effects have been observed in hyphenated techniques. Herein, we report the first example of water treatment under simultaneous hydrodynamic cavitation and plasma discharge with the intense generation of radicals, UV light, shock waves and charged particles. This highly reactive environment is well suited to the bulk treatment of polluted water (i.e. E. coli disinfection and organic pollutant degradation). We have developed a new prototype and have efficiently applied this hybrid technology to water disinfection and the complete degradation of methanol in water with the aim of demonstrating its scalability. We have analyzed the mechanisms of water disinfection under the abovementioned conditions and verified them by measuring cavitation noise spectra and plasma emission spectra. We have also used the degradation of textile dyes and methanol solutions as an indicator for the formation of radicals.
The importance of work is due to the importance of water in the continuation of human life and its great role in practicing its various activities, which concern industry, agriculture and various ...fields. The research methods included the increasing scarcity of water resources resulting from the decrease in the quantities available to the individual, the deterioration of the quantity and the objectives of economic and social development, thus imposing the development and definition of a water management strategy in the medium and long term. In recent years, the water scarcity crisis has increased and exacerbated due to the drought wave that the region suffers from, and it has greatly affected the region. As a result of the research, by the year 2025, a deficit of one billion cubic meters of water will be recorded. It is also possible to avoid this deficit in the hydrographic region of Constantine – Seybousse – and this is due to the dams that are in the process of being completed. In order to eliminate the shortage of water in the region, the amount of storage in dams must be increased and water desalination plants should be established in several areas in order to re-use wastewater. We can also avoid the shortage in the amount of water by building small dams and hill reservoirs, and this is to avoid siltation in large dams. Among the solutions are also increasing surface and groundwater resources, searching for new resources, dealing with losses, and improving the quality of available water.
A new species of Laelaspis from Russia - Laelaspis formicaphilus sp. nov. - is described from the nest of the ant Formica cunicularia Latreille (Hymenoptera, Formicidae) from European Russia. Adult ...female and male specimens are described, compared with similar species, and the nature of Laelaspis-ant associations briefly discussed.
http://www.zoobank.org/urn:lsid:zoobank.org:480FF0AF-527E-4654-9A9F-593A731F8B7E
http://www.zoobank.org/urn:lsid:zoobank.org:act:64B886E1-C216-4450-BFE5-372C43C1102E
•The effect of ultrasound on viscosity of oil in well conditions was investigated.•A long lasting decrease in viscosity can be obtained only by sonochemical treatment.•The use of ultrasound may ...facilitate the production of viscous hydrocarbons.
Reduction of oil viscosity is of great importance for the petroleum industry since it contributes a lot to the facilitation of pipeline transportation of oil. This study analyzes the capability of acoustic waves to decrease the viscosity of oil during its commercial production. Three types of equipment were tested: an ultrasonic emitter that is located directly in the well and affects oil during its production and two types of acoustic machines to be located at the wellhead and perform acoustic treatment after oil extraction: a setup for ultrasonic hydrodynamic treatment and a flow-through ultrasonic reactor. In our case, the two acoustic machines were rebuilt and tested in the laboratory. The viscosity of oil was measured before and after both types of acoustic treatment; and 2, 24 and 48h after ultrasonic treatment and 1 and 4h after hydrodynamic treatment in order to estimate the constancy of viscosity reduction. The viscosity reduction achieved by acoustic waves was compared to the viscosity reduction achieved by acoustic waves jointly with solvents. It was shown, that regardless of the form of powerful acoustic impact, a long lasting decrease in viscosity can be obtained only if sonochemical treatment is used. Using sonochemical treatment based on ultrasonic hydrodynamic treatment a viscosity reduction by 72,46% was achieved. However, the reduction in viscosity by 16%, which was demonstrated using the ultrasonic downhole tool in the well without addition of chemicals, is high enough to facilitate the production of viscous hydrocarbons.
•We studied the sol-gel method for the titanium dioxide nanoparticles synthesis from titanyl sulphate.•We studied the synthesis of titanium dioxide and zinc oxide nanoparticles via sol-gel ...method.•The nanoparticles were synthesized near textile fibers and deposited on them in the same process via ultrasound.•Coated fabrics showed a suppression level of E. coli of more than 99.99% and the antibacterial activity of more than 1.8.•Such textiles can be used to prevent the spread of the nosocomial and other infections.
To prevent possible spread of nosocomial infections – HAI (Healthcare Acquired Infections) in healthcare facilities, Antibacterial textiles are developed. This carried out study has been conducted to assess the feasibility of the method of obtaining antibacterial coatings on textile materials. Specifically, the sol-gel method for synthesis of titanium dioxide nanoparticles in combination with zinc oxide nanoparticles from titanyl sulphate and zinc nitrate hexahydrate has been investigated.
During the synthesis of titanium dioxide nanoparticles in combination with the zinc oxide nanoparticles, the coated textile material showed stable antibacterial properties with a suppression level ofEscherichia coliof more than 99.99%. The method has been tested on a semi-industrial scale in roll-to-roll experimentby applying homogenous coatings at a speed of 1,5 m per minute.
•A sonochemical method is developed to enhance oil recovery from horizontal oil wells.•Ultrasound can enhance the effect of chemicals used to improve the performance of wells.•The method increases ...the permeability of the wellbore perforation zone and reduces blockages.•Field tests of the sonochemical method of EOR in vertical and horizontal wells have shown a significant improvement in oil production.
Oil production from wells reduces with time and the well becomes uneconomic unless enhanced oil recovery (EOR) methods are applied. There are a number of methods currently available and each has specific advantages and disadvantages depending on conditions. Currently there is a big demand for new or improved technologies in this field, the hope is that these might also be applicable to wells which have already been the subject of EOR. The sonochemical method of EOR is one of the most promising methods and is important in that it can also be applied for the treatment of horizontal wells. The present article reports the theoretical background of the developed sonochemical technology for EOR in horizontal wells; describes the requirements to the equipment needed to embody the technology. The results of the first field tests of the technology are reported.
•A down hole method for ultrasonic treatment is developed to enhance oil recovery on failing oil wells.•The method increases the permeability of the bottom hole zone and reduces blockages.•The method ...is simple, environmentally safe and is successful in up to 85% of cases.•The effect due to ultrasonic treatment lasts for 3–12months.
A new method for the ultrasonic enhancement of oil recovery from failing wells is described. The technology involves lowering a source of power ultrasound to the bottom of the well either for a short treatment before removal or as a permanent placement for intermittent use. In wells where the permeability is above 20mD and the porosity is greater than 15% ultrasonic treatment can increase oil production by up to 50% and in some cases even more. For wells of lower permeability and porosity ultrasonic treatment alone is less successful but high production rates can be achieved when ultrasound is applied in conjunction with chemicals. An average productivity increase of nearly 3 fold can be achieved for this type of production well using the combined ultrasound with chemical treatment technology.
A new species, Adactylidium europaeum n. sp. (Acari: Acarophenacidae), is described based on phoretic females collected on thorax of larvae of Phlaeothrips sp. (Thysanoptera: Phlaeothripidae) in ...European Russia. An updated key to the species of Adactylidium is provided.
With each passing year since the Chernobyl accident of 1986, more questions arise about the potential for organisms to adapt to radiation exposure. Often this is thought to be attributed to somatic ...and germline mutation rates in various organisms. We analyzed the adaptability of native Arabidopsis plants collected from areas with different levels of contamination around the Chernobyl nuclear power plant from 1986 to 1992. Notably, progeny of Chernobyl plants resisted higher concentrations of the mutagens Rose Bengal and methyl methane sulfonate. We analyzed the possible molecular mechanisms of their resistance to mutagens and found a more than 10-fold lower frequency of extrachromosomal homologous recombination, significant differences in the expression of radical scavenging (CAT1 and FSD3) and DNA-repair (RAD1 and RAD51-like) genes upon exposure to mutagens (Rose Bengal and x-rays), and a higher level of global genome methylation. This data suggests that adaptation to ionizing radiation is a complex process involving epigenetic regulation of gene expression and genome stabilization that improves plants' resistance to environmental mutagens.
This paper reports the results of the large-scale field testing of composite materials with antibacterial properties in a tropical climate. The composite materials, based on a cotton fabric with a ...coating of metal oxide nanoparticles (TiO2 and/or ZnO), were produced using high-power ultrasonic treatment. The antibacterial properties of the materials were studied in laboratory tests on solid and liquid nutrient media using bacteria of different taxonomic groups (Escherichia coli, Chromobacterium violaceum, Pseudomonas chlororaphis). On solid media, the coatings were able to achieve a >50% decrease in the number of bacteria. The field tests were carried out in a tropical climate, at the Climate test station “Hoa Lac” (Hanoi city, Vietnam). The composite materials demonstrated long-term antibacterial activity in the tropical climate: the number of microorganisms remained within the range of 1–3% in comparison with the control sample for the duration of the experiment (3 months). Ten of the microorganisms that most frequently occurred on the surface of the coated textiles were identified. The bacteria were harmless, while the fungi were pathogenic and contributed to fabric deterioration. Tensile strength deterioration was also studied, with the fabrics coated with metal oxides demonstrating a better preservation of their mechanical characteristics over time, (there was a 42% tensile strength decrease for the reference non-coated sample and a 21% decrease for the sample with a ZnO + CTAB coating).
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