Air Ions Research Articles

Ландшафтно-рекреационный потенциал терренкуров Национального парка «Кисловодский»

Abstract. The objective of the research was to develop terrain cure routes and study the landscape and recreative potential of the Kislovodsk National Park. The Kislovodsk National Park has a unique health-improving potential: green areas of the park, favorable climate, mineral waters, which create the necessary comfort level for recovery, treatment, rehabilitation and health maintenance. Materials and methods. The research was conducted on February 20-22, 2024 in the Kislovodsk National Park with the application of route landscape and climatic observations, as well as an assessment of human physical capabilities, using the example of a woman aged 31 years, height 165 cm and weight 56 kg. Results. Researchers of the Center of Biomedical Technologies (North-Caucasian Federal Research-Clinical Center) have developed two terrain cure routes: Route No 1 and Route No 2. According to the classification, the Route No 1 is considered difficult, the route’s length is 1600 m, angle of elevation – not more than 4°, completion time – 30-40 minutes, the pulse zone No 1 is mainly a light activity zone. The whole route runs through the lower part of the park and is protected from direct sunlight and, deep in the valley, from winds. The path is mostly flat, but has slopes in some locations. According to the classification, the Route No 2, developed from the “Orion” athlete rehabilitation and recovery center (North-Caucasian Federal Research-Clinical Center), is also considered difficult, the route’s length – 2600 m, angle of elevation – up to 13°, completion time – 50-60 minutes, the pulse zone No 1 is mainly a light activity zone. The route is also characterized by a long ascent and steep descent. Conclusion. The comprehensive analysis of the Kislovodsk National Park’s landscape modules proves that the landscape and climatic potential is high enough – 2.8 points out of 3.0 possible. It conditionally corresponds to the sparingly training effect on the human body, gives the possibility to conduct air therapy, heliotherapy, natural air and plant ion therapy in the low altitude conditions to prevent UV-insufficiency, increasing the resistance of the human body to physical stress and accelerating the recovery processes.

DEVELOPMENT AND RESEARCH OF THE FUNCTIONAL POSSIBILITIES OF THE AUTOMATED FUZZY INDOOR AIR QUALITY MANAGEMENT SYSTEM OF PRODUCTION PREMISES

Purpose. Development of a fuzzy indoor air quality control system and research of the efficiency of an automated complex for increasing the concentration of air ions, namely a small-sized ultrasonic generator of air ions and a pump unit in the conditions of a complex ventilated air environment of work premises. Design/methodology/approach. The comprehensive research carried out is important in the context of the development of measures and means and the research of their effectiveness in maintaining the aeroionic regime of industrial premises at the regulatory level. Conclusions. The structure of an intelligent indoor air quality control system is proposed, which implements a combined change in the rotation speed of the fan and pump and the power of the ultrasonic aeroion generator. For the first time, a formalized criterion for the optimality of the indoor air quality management system is proposed, which depends on individual preferences of people regarding the comfort of the production environment and standardized parameters of temperature, relative humidity, and concentration of air ions in the working space. The task of the intelligent control system is to minimize the proposed criterion. Limitations/consequences of research. The proposed recommendations are universal and can be used in various areas of business to create safe and harmless working conditions in production. Practical consequences. The use of the developed small-sized ultrasonic aeroion generator not only significantly increases the concentration of aeroions in the working area, but also due to the baloelectric effect minimizes the negative impact inherent in most existing ionizers, namely the generation of ozone and nitrogen oxide, which significantly improves indoor air quality and thereby increases the level of industrial safety and labor protection. Originality/meaning. The existing control systems assume that standard ionizers (corona discharges) are inserted in the room, so there was a need to develop and research a modern intelligent system for controlling the quality of the indoor air in the working area of industrial premises using an aeroion generator and automated displacement ventilation.

The Effect of Air Ionization in Testing Perovskite-Based Direct Conversion X-ray Detectors

The Effect of Air Ionization in Testing Perovskite-Based Direct Conversion X-ray Detectors

Study on the Comprehensive Health Effects of Coastal Green Areas in Qingdao City, China

The recuperation factors (negative air ion concentration, airborne particulate matter, human comfort index, and acoustic environment index) of coastal green spaces have significant health effects. Most current studies focus on the distribution pattern of single recuperation factors in the forest environment; however, the comprehensive health effects of coastal green spaces are still unknown. To address this, we analyzed the distribution patterns of single and comprehensive health factors in different landscape configurations, landscape compositions, and coastal distances by principal component analysis and systematic clustering. The results show that: (1) coniferous and broadleaf mixed forests exhibit higher integrated health benefits than other landscape compositions; (2) closed and partially closed landscape configurations exhibit enhanced potential for promoting health benefits as opposed to partially open and open spaces; (3) a coastal distance of 150–300 m offers the strongest comprehensive health benefits. These findings collectively suggest that the increased cultivation of closed and partially closed mixed coniferous and broadleaf forest species at a distance of 150–300 m could effectively provide higher comprehensive health effects. Our study complements the ecosystem service of coastal green areas, especially in coastal health ecological services, providing support for coastal rehabilitation landscape planning; and can help to guide tourists in scheduling coastal health activities scientifically.

A cyclone formation, eastward plume drag, ion-hydration process, and the consequent ionospheric changes following the 2022 Hunga Tonga-Hunga Ha'apai volcanic eruption

In this paper, we investigate the possible mechanism behind the volcanic plume drag and the massive expansion of the ionospheric Total Electron Content (TEC) along the eastern longitudes by using near-field observations of the 15 January 2022 Hunga Tong-Hunga Ha'apai volcanic eruption. The meteorological omega parameter shows a dominant upward/downward movement of the air parcels along the eastern and southern sides of the volcanic eruption. This dominant air convection under the presence of the heavy moisture of volcanic plume and vector winds indicated the formation of a cyclone over and around the Tonga volcano. This cyclone dragged the heavy volcanic plume towards the eastern longitudes (150oE – 180oE). Moreover, we observe that the volcanic plume injected about 5 DU of Sulfur Dioxide (SO2) and 30 kgm−2 of the water content along the total atmospheric column. The chain reactions of Hunga Tonga volcanic trace gases with the gases present in the neutral atmosphere instigated an air ionization process, while under the presence of the heavy water content, these ions underwent an ion-hydration process that contributed to the electrodynamical changes in the region. These electrodynamical changes can be regarded as Atmospheric Chemical Potential (ACP) in the lower atmosphere. We observe a sharp increase in the ACP of ∼0.26 eV along the eastern longitudes (160–180°E) exactly above the dragged volcanic plume area. The long-term TEC changes that have been observed towards the eastern longitudes are the result of the ion-hydration process at the lower atmosphere. The statistical analysis showed a critical change during the day of the event up to ∼48 TECU with an increasing value of 28 and 18 TECU from the lowest and highest ranges before the event over the crater, respectively. Our main findings showed ionospheric anomalies in the near field started from 6:00 to 16:00 UTC. Based on Swarm satellites, the S4 values have significant changes around 0.3–0.6 lasting for tens of minutes.

Study on the negative oxygen ion release behavior and mechanism of tourmaline composites

Negative air ions are becoming increasingly popular as they purify the air by adsorbing dust and hazardous substances, which are beneficial to people's health. The ternary composites of tourmaline and monazite with graphene, germanium, cerium oxide, lanthanum oxide, and titanium oxide were prepared by the ball milling process, and the release of negative oxygen ions was investigated. The enhanced mechanism of tourmaline is analyzed systematically by hysteresis loop with monazite and other substances. The results indicate that monazite relies on its thorium element to generate radioactive energy to excite negative ions. It was discovered that the T/10%M/15%CeO2 composites exhibited the optimum negative ion release performance of 6580 ions/cm3, which is approximately 5–6 times compared to tourmaline. The results of conductivity and hysteresis loop tests demonstrate that tourmaline stimulates negative oxygen ions due to its spontaneous polarization effect and the formation of a polarized electric field. The spontaneous polarization effect of tourmaline is positively correlated with the release amount of negative oxygen ions.

Experimental Study on the Combustion of Flexible Polyurethane Foam Under Marine Environment Conditions

ABSTRACTThe common upholstered furniture filler flexible polyurethane foam (FPUF) is a synthetic polymer whose wide range of application environments include not only land but also sea, especially in ship cabins, where FUPF is used extensively to improve the comfort and aesthetics of passenger cabins. In marine air, halogen ions in marine air can act as quenchers of gas-phase radicals, blocking the conversion of CO to CO2 in the combustion of polyurethane foam, which causes different combustion characteristics of FPUF. Therefore, the combustion characteristics of FPUF and the content of asphyxiating gas components in the combustion flue gas were studied by using a conical calorimeter and a steady-state tube furnace (SSTF) to simulate a marine air environment with high salinity and humidity, as well as the fractional effective dose (FED) model to evaluate the flue gas toxicity. The results show that the heat release rate (HRR) curves of FPUF combustion are similar for pilot ignition and non-pilot ignition modes in air with different salinity and humidity, and the ignition time of FPUF will increase about 1% with the salinity of air droplets increase 1% in both non-pilot and pilot ignition modes. The variation of flue gas components from FPUF combustion in air with different salinity and humidity has a similar pattern: the generation of CO and HCN increases with increasing Φ values (the ratio of actual fuel-air ratio to the ratio of stoichiometric fuel-air ratio), while the generation of CO2 and NO decreases with increasing Φ values. When the Φ value is is close to 0.9 or 2.33, the ventilation conditions play a dominant role in the generation of each component in the flue gas. And the air with high salinity and humidity has a greater effect on the generation of each flue gas component when the equivalent ratio Φ is in the range of 0.9 to 1.8. As the salinity in air increases, the threshold for FED to reach danger shifts from Φ = 1.61 to Φ = 1.36. The presence of NaCl in the air with high salinity and humidity increases the generation of asphyxiating gas components in FPUF combustion, the study has practical implications for evacuation, toxicity prediction, and safety evaluation.

LiDAR Sensing of Aerosols Induced by Air Ions

LiDAR Sensing of Aerosols Induced by Air Ions

Field electron emission in the atmospheric pressure range

Field emission is a well-known technology for generating electrons under vacuum conditions. Here we assess whether gated silicon field emitter microstructures, originally developed for use in space, can ionise air for electroaerodynamic propulsion and other applications. Electron range in air is compared to breakdown voltage over the atmospheric pressure range, to evaluate whether an operational region exists for which the geometry permits electrons to escape and ionise, whilst keeping the voltage low enough to avoid breakdown. An operational region is identified between 500–100 V for pressures corresponding to 0–20 km altitude. This offers low-power and low-mass operation in comparison to existing ionisation technologies. Carbon nanotube field emitters may offer enhanced performance over the silicon emitters. Field electron emission represents a new air ionisation technology which may be appropriate for light-weight, high-altitude aircraft propulsion.

Bipolar ionization rapidly inactivates real-world, airborne concentrations of infective respiratory viruses.

The SARS-CoV-2 (COVID-19) pandemic has highlighted the urgent need for strategies that rapidly inactivate airborne respiratory viruses and break the transmission cycle of indoor spaces. Air ions can reduce viable bacteria, mold, and virus counts, however, most studies use small test enclosures with target microbes and ion sources in close vicinity. To evaluate ion performance in real-world spaces, experiments were conducted in a large, room-size BSL-3 Chamber. Negative and positive ions were delivered simultaneously using a commercially available bipolar air ion device. The device housed Needle Point Bipolar ionization (NPBI) technology. Large chamber studies often use unrealistically high virus concentrations to ensure measurable virus is present at the trial end. However, excessively high viral concentrations bias air cleaning devices towards underperformance. Hence, devices that provide a substantial impact for protecting occupants in real-world spaces with real-world virus concentrations are often dismissed as poor performers. Herein, both real-world and excessive virus concentrations were studied using Influenza A and B, Human Respiratory Syncytial Virus (RSV), and the SARS-CoV-2 Alpha and Delta strains. The average ion concentrations ranged from 4,100 to 24,000 per polarity over 60-minute and 30-minute time trials. The reduction rate was considerably greater for trials that used real-world virus concentrations, reducing infectivity for Influenza A and B, RSV, and SARS-CoV-2 Delta by 88.3-99.98% in 30 minutes, whereas trials using in-excess concentrations showed 49.5-61.2% in 30 minutes. These findings strongly support the addition of NPBI ion technology to building management strategies aimed to protect occupants from contracting and spreading infective respiratory viruses indoors.

The Ecological Healthcare Benefits and Influences of Plant Communities in Urban Wetland Parks

Plant communities in urban wetland parks (UWP) have significant eco-healthcare benefits in terms of regulating the climate and improving the human living environment. However, factors influencing the regulation of eco-healthcare benefits are unclear. Taking Huaxi Ten Mile Beach National Urban Wetland Park as an example, the urban wetland park comprehensive healthcare index (UPCHI) was constructed based on an outdoor survey and indoor analysis to evaluate the UWP’s eco-healthcare benefits. Pathway analysis was used to investigate how climatic, geographic, and plant factors interact to affect the UPCHI. The results show that, over the whole year, tree–shrub–herb showed the best performance in terms of reducing PM2.5, PM10, and noise, as well as raising negative air ion concentrations; however, human comfort performed the worst. The UPCHI was generally beyond level Ⅲ (0.49–0.58) in the spring and summer, indicating that there are eco-healthcare benefits. Overall, the deciduous tree–shrub–herb community had the highest annual mean UPCHI, and more than half of the plant communities’ eco-healthcare benefits were class Ⅱ, which is very beneficial for eco-healthcare. The main direct factors on UPCHI were illumination intensity (0.68) and tree height (0.90), while canopy height (0.64–0.59) and tree crown radius/canopy height (0.72–0.14) directly or indirectly influenced UPCHI. The distance from the edge of the mountain (−0.39–−0.322) had a direct negative, but minor, effect on UPCHI. This study will assist residents with selecting suitable times and places for wetland recreation and healthcare activities, and it offers a valuable reference for the future planning and design of UWP plant communities.

Temporal Variation Characteristics of Negative Air ion Concentration and Air Quality Evaluation in Songshan National Nature Reserve, Beijing

Temporal Variation Characteristics of Negative Air ion Concentration and Air Quality Evaluation in Songshan National Nature Reserve, Beijing

A system for monitoring the microclimate parameters of premises based on the Internet of Things and edge devices

Recent years have been characterized by the rapid development of Internet of Things (IoT) and edge device technologies. Systems of various purposes with IoT elements and edge devices are increasingly finding practical use in people’s lives, the IoT element base is expanding and improving, which makes it possible to develop effective measuring systems, including those with feedback control. An essential role in ensuring people’s lives is played by the microclimate of the premises where people live, work, and study. As you know, the excess or decrease of the environmental microclimate relative to the norm negatively affects the physiological state of a person, his performance, and concentration and reduces the efficiency of work and training. Therefore, in this work, the problem of round-the-clock monitoring of the microclimate of classrooms is solved by developing an autonomous IoT system using edge devices to measure climatic parameters such as temperature, relative humidity, carbon dioxide level in the air, and the concentration of light air ions with data recording on a smartphone and saving on a remote server. The principles of building microclimate monitoring systems are presented, the requirements for the system are set, the criteria for choosing the elemental base and the technical characteristics of each component are given. The structure of the air ion concentration sensor developed by the author and the method of measuring the air ion concentration in the room are also described. The structural diagram of the developed microclimate parameters monitoring system is also presented. The development is part of a system for studying the influence of microclimate parameters on the physiological state of applicants for education. The results obtained in the work will allow development measures to ensure the necessary normal conditions for training in confined spaces. Research conducted using the developed system will allow better formation of student learning conditions in order to achieve maximum performance indicators.

Simultaneous observations of atmospheric vertical potential gradient from coastal Antarctic stations Bharati and Maitri

Simultaneous observations of the atmospheric electric potential gradient (PG) at Bharati and Maitri stations were studied from 2014 to 2016. A new regional diurnal pattern of fair-weather PG for the coastal Antarctic region, perhaps the ubiquitous characteristics of the PG for the coastal Antarctic region, has been identified. This pattern has a significant broad minimum around noon hours. It is around this time the wind speed is also maximum. The PG data of past years of Syowa, Vostok, and Carnegie Cruise were also used in this study. The surface wind distorts the fair-weather diurnal pattern of PG over Bharati more intensely than at Maitri. The katabatic wind effect on the PG at Bharati appears to be more intense than at Maitri. The topography and katabatic winds associated with the Lambert glacier could be the reason. The observation of Bipolar Air Ion Concentration (BAIC) suggests that the wind speed significantly affects the concentration by accumulation and dispersion. The concentration is maximum when the wind speed is minimum. As the air ion concentration controls the conductivity, the PG is expected to be minimum during these hours to produce an anomalous diurnal pattern in the PG at Bharati. Data quality is improved by measuring the PG with a field monitor at the surface level instead of at an elevated position. This study provides new hope in pursuing globally representative data of the PG for further investigations on the global thunderstorm activity and the solar-terrestrial weather relationship.

Current-voltage characteristics of single-stage semiconductor magnetic pulse generators with a distinctive structure of the conversion link in the input circuit

Introduction. The main feature of the semiconductor magnetic pulse generators (SMPGs) is a slow accumulation of energy in the primary capacitor and its rapid introduction into the load by using a series of sequentially connected magnetic compression stages. Initially, these devices were mainly used for pumping gas lasers, but over the last decade SMPGs have been increasingly used in electric discharge technologies for water purification and air ionization to remove toxic impurities. At the same time, along with the practice of using these devices, development has also been achieved in the principles of their design and methods of mathematical modeling. Problem. The main drawback of the existing theory of SMPG’s stationary oscillations mode is an adoption of the saturable reactor (SR) model in approximation of the static magnetization curve of its core, as well as unidirectional nature of the energy transfer from the generator to the load. In most publication the exchange processes between the power source and SR are still not covered. Goal. Study of electrical and energy characteristics of low-voltage single-stage SMPG devices with series and parallel conversion stages in the charging circuit. Methodology. To achieve the set goal, this work uses comprehensive approach relayed on technical tools of setting up the experiment, numerical methods for processing measurement results, as well as an analytical method for describing electromagnetic processes in single-stage SMPG circuits. Results. The closed current-voltage characteristics of the SR are obtained, according to which the numerical calculations of the integral magnetic and energy characteristics of the proposed models are carried out. The features of the longitudinal capacitance charging process in a SMPG’s circuit with a parallel conversion stage, which occurs simultaneously in two adjacent circuits, are explained. Analytical expressions to describe the dynamics of magnetic flux density in the SR’s core as a time-depended function are derived. Based on the obtained hysteresis curve of the core, the exchange processes of energy transfer between the power source and the SR are explained. Practical value. The results of the research can be applied in the development of low-voltage SMPG circuits with improved energy-dynamic parameters.

Characterization of a circular arc electron source for a self-neutralizing air-breathing plasma thruster

The paper presents an enhanced version of an arc electron source designed for air ionization applications in a self-neutralizing air-breathing plasma thruster. The arc electron source is specifically suited for the air-breathing plasma thruster, as it allows precise control of mean electron energy levels. This paper focuses on the ionization aspects of air-breathing thrusters through the development of axially magnetized arc electron sources. The sources consist of a circular and coaxial configuration of a metallic arc plasma source coupled with a positively biased grid to extract electrons and control mean electron energy. The average mean electron energy of electrons in the arc electron source is regulated by adjusting the bias voltage of the grid within the range of 0 V – 300 V. To investigate the behavior of ion current density and electron density concerning pressure and mean electron energy, the current probe and magnetic filter were utilized. It was demonstrated that the circular electron source leads to enhanced ionization of airflow by achieving plasma densities greater than 1018 m−3. By utilizing a high-speed camera for the circular arc electron source, the arc spot was seen to move azimuthally due to the magnetic field. Furthermore, scanning electron microscopy and a conductance measurement system were employed for the coaxial arc electron source to examine the deposition and conductance of the electron extraction grid. While the grid underwent deposition of about 600 microns, the conductance was observed to increase/saturate with time and bias voltage, indicating an electrically “self-healing material”.

Nonlinear propagation calculation-based irradiation process control for several mJ ultrashort pulse laser processing

In the realm of ultrashort pulse laser processing, surpassing the air ionization threshold, variations in focusing characteristics due to nonlinear optical phenomena pose challenges. Particularly, suitable irradiation conditions and position control methods for high pulse energy processing around 1 mJ remain unestablished. This study explores laser divergence phenomena in several mJ pulse energy range, examining both experimental and computational data. Quantitative demonstrations of laser focusing alterations, including divergence position and fluence, were achieved. Additionally, the dry laser peening effect was enhanced by energy-specific irradiation control. Numerical simulation-based visualization facilitates precise control, advancing the processing techniques.

Analysis of a UV photocatalytic oxidation-based disinfection system for hydroxyl radicals, negative air ions generation and their impact on inactivation of pathogenic micro-organisms.

This work presents a large-scale surface disinfection system, which has a unique lantern arrangement of ultraviolet-C (UV-C) light (254nm) in conjunction with nanotechnology in a protective biosafety environment. Shadow regions are best dealt in this system by the generation of hydroxyl radicals (•OH) and negative air ions at sites where UV light cannot penetrate. More than 35 000 negative air ions/cm3 along with •OH were produced continuously in the disinfection chamber through the advanced photocatalytic oxidation process [UV-C + titanium dioxide (TiO2)]. The arrangement has been made to provide an optimized UV irradiation (∼2 mW/cm2) throughout the disinfection system. In order to distinguish between effects arising from (i) the action of UV dose alone and (ii) the action of UV dose along with •OH and negative air ions, E. coli and P. aeruginosa were chosen for bacterial testing and two interventions were made. The first intervention involved placing only UV lamps in the disinfection chamber to see the effect of only UV dose on bacterial inactivation efficiency. The second intervention involved placing the TiO2 nanoparticle coated aluminum plates along with UV lamps; this allows for the generation of negative air ions and •OH inside the disinfection chamber and enhanced bacterial inactivation efficiency. More than 95% bacterial inactivation efficiency has been reported in the case of UV-C + TiO2 compared to only 77% in UV only at the same time interval (90s).

Evaluation of the Superiority of Lightweight-Aggregate-Concrete Prestressed Box Girders in Terms of Durability and Prestress Loss.

This case study aimed to compare the differences in the durability and prestress loss between normal-weight-concrete (NC) and lightweight-aggregate-concrete (LWC) prestressed box girders, which were constructed at the same time in the same area, so as to verify the superiority of using synthetic lightweight aggregate (LWA) made from reservoir sediments in prestressed bridges. For the NCs and LWCs used in the prestressed box girders, the basic mechanical properties (compressive strength, flexural strength, splitting tensile strength, and elastic modulus) were tested, as well as the durability properties (chloride ion penetration resistance and rapid chloride permeability). Then, through the prestress-monitoring system, the prestress losses of the two groups of prestressed box girders were tracked. The results of the durability test confirmed that LWC can inhibit the penetration of air, water, and chloride ions by strengthening the interfacial transition zone between the aggregate and the cement paste, thereby improving its durability. Moreover, the magnetic-flux prestress loss of the NC prestressed box girder reached 8.1%. In contrast, the magnetic-flux prestress losses on both sides of the LWC prestressed box girder were 4.6% and 4.9%, respectively. This verified that, under the same environmental conditions, the use of LWC produced less of a prestress loss than the use of NC.

Experiment and simulation of electron density distribution in discharge plasma at hypersonic speed

Pulsed discharge can generate high density and high dynamic plasma, which has promising application prospects in the field of stealth technology for high-speed aircraft. To study the evolution process of pulsed discharge plasma jet in a hypersonic flow field, the pulsed discharge experiment was performed in a hypersonic wind tunnel with 8 M in this paper. The plasma evolution process and electron density were measured by a high-speed schlieren device and spectrum acquisition system. A shock wave appeared after the blast wave generated by the discharge interacted with the external flow field. In the region below the shock wave, the plasma jet flowed downstream and produced a plasma layer. The electron density of the jet increases with the injected energy, and the peak density reaches 5.28 × 1015 cm−3. Due to the limitations of experimental measurements, based on the Navier–Stokes equations and the air dissociation and ionization model, including 11 components and 20 chemical reactions, a simulation for the experimental process was performed. At the injected energy of 495 and 880 mJ, the difference between the simulated electron density and the experimental value is 16.09% and 15.34%, respectively. The thickness of the plasma layer initially increases and then decreases over time, with higher injected energy leading to a thicker layer. Specifically, when 880 mJ of energy is injected, the plasma layer can reach a maximum thickness of 6.69 cm. The collision frequency fluctuates around 1 GHz, and the collision frequency at the upper edge of the plasma layer is large.