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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.
Flexible materials, such as fabric, paper and plastic, with nanoscale particles that possess antimicrobial properties have a significant potential for the use in the healthcare sector and many other ...areas. The development of new antimicrobial coating formulations is an urgent topic, as such materials could reduce the risk of infection in hospitals and everyday life. To select the optimal composition, a comprehensive analysis that takes into account all the advantages and disadvantages in each specific case must be performed. In this study, we obtained an antimicrobial textile with a 100% suppression of E. coli on its surface. These CeO2 nanocoatings exhibit low toxicity, are easy to manufacture and have a high level of antimicrobial properties even at very low CeO2 concentrations. High-power ultrasonic treatment was used to coat the surface of cotton fabric with CeO2 nanoparticles.
•The use of 3 different types of waveguide systems for activation of ASFC reagents was investigated.•Ultrasound enables to reactivate the alumosilicic flocculant-coagulant.•In scaled up reactors the ...choice of the equipment type affects the stability of the achieved effect.
Acoustic fields formed during operation of ultrasonic reactors with waveguides of following types: rod-type, cylindrical with rectangular protrusions and tubular were calculated and measured. The influence of distribution of acoustic fields arising from the operation of waveguide systems of three different types on the efficiency of ultrasonic activation of alumosilicic flocculant-coagulant and magnetite intended for water purification was investigated. It was shown that regardless of the equipment used on an industrial scale it is possible to reactivate the alumosilicic flocculant-coagulant even after the shelf life period of it passed, however in case of activation of magnetite the use of a bigger reactor in inefficient.
In case of industrial scale processes, the choice of the correct reactor design is of significant importance, since it allows to reduce the required processing time, and, as a result, the energy consumption of the processes. The advantages of tubular waveguide systems include the possibility of processing large volumes of liquid. The high efficiency and uniformity of the excited ultrasonic fields can lead to reduction of operating costs. In case of smaller flows, the waveguide system with rectangular protrusions allowed to obtain better results.
Our work illustrates the dependence of the success of a specific method on the choice of the waveguide and the size of the reactor during upscale.
Water disinfection and potential sterilization in continuous flow was achieved in a hybrid reactor with a broadband hydrodynamic emitter combined with ultrasonic vibrations at different frequencies ...and with excess pressure. Such a combination showed synergistic effects by increasing the acoustic power in the reactor vortex flow. The present combined physical treatment, compared with sonication alone, could increase microorganism inactivation by 15–20%.
TThe proposed work covers the tasks of such areas as reducing input currents and bias voltage of integrated operational amplifiers (ICs OA) manufactured according to BiFET technology, the prospect of ...using JFET transistors in digital circuit technology, Si CMOS technology at 22 nm node and beyond, manufacturing bipolar transistors on ultra-thin layers of the active base and emitter, increasing resistance of ICs to external influences. The main method of experimental investigation of channeling is the construction of impurity distribution profiles using SIMS. In this work to study the channeling effect of boron and phosphorus in silicon was chosen the method for constructing the response surface of the saturation current of JFET for a silicon wafer. The choice of method was based on the high sensitivity of the cut-off voltage and saturation current of the JFET transistor to the channel thickness and impurity concentration in it, the relative simplicity of performance and practical benefits in improving BiFET technology.
This publication presents results of a study of everyday ethnocultural adaptation of newly arrived and indigenous populations in Khanty-Mansi Autonomous Okrug – Yugra. A survey has helped identify ...levels of frustration in newly arrived and indigenous populations. The authors have concluded that ethnocultural adaptation of newly arrived population is slow and patchy. The newly arrived population is more frustrated than the indigenous community is. To reduce the level of frustration, the newly arrived population needs to connect with ethnic customs and traditions of indigenous small numbered peoples of the North, understand how unique they are and ensure ethnic tolerance on both sides.
Bilingual training of international students is a vocational training of learners with the use of two languages – English/French and Russian where the latter is a foreign language. The cultural ...approach regards culture as a key component integrated in science classes and humanities as well as language ones, aimed at cultural awareness that the students will heighten through constant reflection about the Self and the Others in order to develop linguistic and intercultural competences and facilitate a better understanding of a broader range of vocational contexts (scientific, social, clinical, political etc.) that the students are exposed to. Questionnaires, oral and written reports, classroom observations and interviews were used to collect the data. The findings show student’s positive perceptions of the cultural approach and highlight the value of explicitly considering a cultural component in content courses. Most students found the cultural approach as an effective way of facilitating intercultural communication and understanding.
The article examines the legal framework for environmental security in the context of globalization. Attention is focused on interstate cooperation in the field of health security. Particular ...attention is paid to the relationship and correlation of international and national legal acts. The task to unite the efforts in the international community for ensuring the safety of the human environment is being actualized. In modern conditions, the depletion of natural resources and the adverse effects of environmental degradation are an obstacle to sustainable development. Negative trends are recognized land degradation, loss of biodiversity, lack of drinking water, droughts, desertification, aggravating new problems. It is concluded that it is necessary to carry out a set of measures to preserve the environment. Issues related to the rational use of natural resources, seas, oceans, freshwater resources, mountains and forests and protection of wild flora and fauna require solutions within the international community. The importance of international cooperation and consolidation of resources to combat desertification, drought and land degradation is increasing. The international community in the field of environmental protection should be focused on the prevention and limitation of harmful effects on the environment, the rational use of international natural resources and the protection of unique natural objects through conservation from human economic influence. Changes are required in the environmental policies and legal frameworks of states. Consolidation is required by the resources of both government agencies and civil society, including youth, trade unions, the media, academia, the private sector and others.
Various types of chemical and physical protocols are used, thermal treatment in particular, to increase the quality of bulk food products (for example, dates or some sort of nuts) and extend shelf ...life, and combinations of methods are frequently used to achieve the best results. However, the use of these processing methods is not always the best option to preserve the initial taste and appearance of food products. For instance, a product may lose its initial natural appearance and acquire different flavors due to chemical transformations that occur at certain temperatures or when the products are treated with chemicals. Non-thermal treatment methods are called “cold” pasteurization. This is a set of advanced techniques that are based on physical and chemical effects that do not result in the structural food-product transformations caused by heating. We have developed and tested a new technique for efficient food-product processing and cold pasteurization in an ultrasonic field under pressure in an atmosphere of supercritical or subcritical carbon dioxide. A laboratory-scale unit that was designed and built for this purpose has experimentally proven the feasibility of this process and demonstrated high efficiency in suppressing pathogenic flora.
Although water contamination with drug residues is a threat to public health, there are currently barely any effective methods of purifying water from pharmaceutical substances. In this study, ...continuous-flow sonoplasma treatment was used for the complete degradation of tetracycline and ciprofloxacin in polluted municipal water. The addition of CeO2 nanoparticles as catalysts significantly increased the degradation rate of the antibiotics, and a degradation degree of 70% was achieved. The presence of reactive oxygen species in the CeO2-nanoparticle-containing sonoplasma-treated system was experimentally proven for the first time using the chemiluminescence technique.
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