Air Ions Research Articles

Synergistic Disinfection by 222 nm Far-UVC and Negative Air Ions of Airborne Bacteria and the Induced Oxidative Stress Responses: A Bioaerosol Chamber Study

Synergistic Disinfection by 222 nm Far-UVC and Negative Air Ions of Airborne Bacteria and the Induced Oxidative Stress Responses: A Bioaerosol Chamber Study

A Review on Pyridine Based Colorimetric and Fluorometric Chemosensor for Detection of Hg2+ ion.

Pyridine, N-containing heterocyclic organic compound, displays strong coordination capabilities with various metal ions. It can be synthesized through various methods, such as Friedlander synthesis, heterocumulene synthesis, cross-coupling reactions, the Radziszewski reaction, Bonnemann cyclization, as well as cobalt-catalyzed synthesis. Experimental and spectroscopic analyses have demonstrated a strong binding affinity between pyridine and several heavy metal ions, including Pb2+, Hg2+, and Cd2+ ions. The escalating environmental pollution caused by the disposal of heavy metal ions in rivers, open air, and water reservoirs poses a significant threat to both ecosystem and human health. To address these environmental challenges, a cost-effective and easily synthesized chemosensor has been prepared for identifying toxic heavy metal ions in various samples. Pyridine's photophysical properties make it an effective sensor for detecting Hg2+ ions, displaying fluorescence quenching or enhancement in their presence. The coordination between pyridine and Hg2+ ions lead to shifts in the absorption spectra. The pyridine-based sensor has been evaluated for its sensitivity, selectivity, and detection limits under different experimental conditions. Pyridine's solubility and environmental stability make it applicable for real-time detection, making pyridine probes valuable tool for monitoring toxic Hg2+ ions in the environment. The results demonstrate that the pyridine-based chemosensor exhibits good selectivity and sensitivity for targeting Hg2+ ions, with detection limits within acceptable ranges. This review (from years 2011 to 2023) emphasizes the preparation of various substituted pyridine compounds as selective, sensitive, and specific sensors for real-time detection of Hg2+ ions.

Non-Thermal Atmospheric Pressure Plasma as an Adjunct to Intestinal Anastomosis: A Pilot Study on Preventing Anastomotic Leaks

Anastomotic leaks remain a significant challenge in intestinal surgery, often leading to severe complications. This study investigated a novel approach to enhance anastomotic healing and reduce the risk of leaks by combining traditional suturing and stapling techniques with non-thermal atmospheric pressure plasma (NTAPP) application. NTAPP, a cold atmospheric plasma generated through the ionization of ambient air, has been shown to possess antimicrobial, hemostatic, and wound-healing properties. NTAPP promotes sterilization, coagulation, and tissue regeneration by generating reactive oxygen and nitrogen species, potentially strengthening anastomotic union. This pilot study evaluated the efficacy of NTAPP in three patients undergoing intestinal anastomosis. Following the standard surgical procedure, NTAPP was applied directly to the anastomotic site. Postoperative outcomes were monitored for six months, including anastomotic leaks and healing rates. Preliminary results demonstrated promising outcomes. All three patients exhibited successful sealing of the anastomosis, with no evidence of leakage during the follow-up period, providing reassurance and confidence in the potential of sutures, staples, and NTAPP. These findings suggest that NTAPP can significantly improve the safety and efficacy of intestinal surgeries by reducing the incidence of anastomotic leaks. While further research with a larger sample is necessary to confirm these initial findings, the results of this study provide a strong foundation for exploring the potential of NTAPP as a valuable adjunct to conventional surgical techniques for preventing anastomotic leaks. This innovative approach could reduce postoperative complications, improve patient outcomes, and enhance the overall quality of care in intestinal surgery.

Empirical analysis of the influence mechanism of vegetation and environment on negative air ion in warm temperate forest ecosystems

Air pollution presents a significant threat to public health in megacities globally. Negative air ions (NAI), often referred to as “air vitamins,” are recognized for their effectiveness in alleviating the harmful effects of air pollution. Forest ecosystems serve as natural generators of NAI, with both vegetation and environmental conditions playing critical roles in the formation and persistence of NAI. Gaining a comprehensive understanding of how forest ecosystems regulate NAI production is essential for leveraging their potential to enhance air quality. However, the intricate dynamics of forest ecosystems, along with seasonal fluctuations in vegetation and environmental factors, introduce uncertainties in NAI generation. This study utilized long-term observational data to explore the relationships between environmental variables, vegetation photosynthetic capacity (using solar-induced chlorophyll fluorescence, SIF), and NAI concentrations. By employing machine learning algorithms, we analyzed the spatiotemporal distribution of NAI, identifying the key contributing factors and their relative influence within forest ecosystems. The results revealed distinct seasonal variations in NAI levels, with higher values in summer and lower in winter. SIF and PM2.5 primarily influenced NAI through direct effects across seasons, whereas ambient temperature (TA), relative humidity, photosynthetically active radiation (PAR), and soil moisture predominantly impacted SIF on NAI through indirect effects in summer. TA was the primary influencing factor in spring and winter, contributing 28% and 25%, respectively, while PAR played a more significant role in summer and autumn, accounting for 37% and 27%. Vegetation had a greater impact on NAI levels during spring and summer, contributing 66% and 62%, whereas environmental factors dominated in autumn and winter, with contributions of 83% and 89%. This study offers both a theoretical foundation and technical guidance for enhancing the role of forest ecosystems in improving air quality and human living environments.

A novel sustainable wood-based negative air anion generator utilizing in-situ polymerization of polylactic acid to reinforce the cellulose framework

The generation of negative air ions (NAI) by furniture contributes to indoor air purification and enhances the living environment. However, commercially available furniture typically relies on surface coatings to release NAI. Over time, the degradation of these coatings leads to a significant decline in NAI release performance, presenting a persistent challenge for sustained effectiveness. Here, a novel sustainable wood-based negative air anion generator (SWNG) had been developed, utilizing a cellulose framework as the substrate. The in-situ synthesis of polylactic acid (PLA) within the wood incorporated titanium dioxide (TiO2), tourmaline (TL), and cellulose acetate, firmly anchoring these materials within the wood structure. Compared to the cellulose framework alone, the NAI production of the SWNG had increased by 406.67 %. The impregnation with PLA enhanced the enduring photocatalytic activity of TiO2 and TL in this innovative wooden NAI generator. After undergoing 200 cycles of testing between −40 °C and 50 °C, it continued to sustain NAI production, demonstrating exceptional antibacterial performance. Overall, this study introduced a novel sustainable wood-based negative air ion generator as a highly stable material with sustainable properties, offering significant potential for applications in improving indoor air quality and in the domain of home construction.

ОБҐРУНТУВАННЯ РОЗШИРЕНОГО СКЛАДУ СПОСТЕРЕЖЕНЬ НА ВОДНО-БАЛАНСОВИХ СТАНЦІЯХ ТА ДОСЛІДНИЦЬКИХ ГІДРОГЕОФІЗИЧНИХ ПОЛІГОНАХ

The current level of understanding of the subordination and multifactorial dependence of the determining processes in the atmosphere, lithosphere and hydrosphere of the Earth requires a corresponding reorganization of the basic system of environmental monitoring, improvement and expansion of research on water these stations, which can become the supporting 'nodes' of the balance of this system. The appearance of fundamentally new theoretical developments, modern devices and equipment, a large number of software tools, etc., prompts a significant reorganization and strengthening of the environmental monitoring system. The article substantiates an additional set of studies, which should be included in the regulation of observations at already existing water balance stations, with their mandatory modernization. Spheres are subject to control - the atmosphere, surface and underground (subsurface) hydrospheres, which change over time at different rates and pedosphere. A certain inertia of hydrogeological processes implies the possibility of using meteorological indicators, which can be used to predict changes in the moisture regime in the aeration zone and shallow groundwater in the near future; based on the reliably predictable changes of the latter - to forecast changes in interlayer groundwater resources, etc. It is proposed to include in the monitoring regulations the following indicators of the state of the environment, which will allow to identify and analyze the causes of changes in the water situation, balance and resources, to determine the mechanisms of moisture transfer and accumulation, as well as to build models and perform predictive assessments. The results of comprehensive research at the «Lutiz» landfill demonstrate significant variability of hydrogeophysical indicators and changes in the intensity of natural signals depending on the landscape timing, the latest tectonics, the geological basis and the composition of the overlying sediments. Original devices are presented, which are used to determine indicators of electric and thermal fields, the ratio of positive and negative air ions, etc.

On the potential of the Cluster Ion Counter (CIC) to observe local new particle formation, condensation sink and growth rate of newly formed particles

Abstract. The Cluster Ion Counter (CIC) is a simple three-channel instrument designed to observe ions in the electrical mobility equivalent diameter range from 1.0 to 5 nm. With the three channels, we can observe concentrations of both ion clusters (sub-2 nm ions) and intermediate ions. Furthermore, as derived here, we can estimate condensation sink (CS), intensity of local new particle formation, growth rate of newly formed particles from 2 to 3 nm and formation rate of 2 nm ions. We compared CIC measurements with those of a multichannel ion spectrometer, the Neutral cluster and Air Ion Spectrometer (NAIS), and found that the concentrations agreed well between the two instruments, with correlation coefficients of 0.89 and 0.86 for sub-2 nm and 2.0–2.3 nm ions, respectively. According to the observations made in Hyytiälä, Finland, and Beijing, China, the ion source rate was estimated to be about two to four ion pairs cm−3 s−1. The new CIC is a simple and cheap instrument that can be used in different environments to obtain information about small ion dynamics, local intermediate ion formation and CS in a robust way when combined with the theoretical framework presented here.

Conceptual model of electrostatic non-ionizing air filter

Abstract Many infectious diseases such as SARS-CoV-2, rhinovirus, adenovirus, and influenza are transmitted through small respiratory droplets and various filtration systems are used to reduce the risk of airborne infection. Here, we develop a conceptual model of a filter, which is based on the electrostatic deposition of air droplets potentially containing pathogens. Within the model, we explore the effect of polarization of neutral spherical droplets moving in an air flow past cylindrical electrodes. The strength of electric field they produce is low enough to eliminate corona discharge and minimize air ionization, but high enough to capture the droplets. Based on the proposed model, we calculate the filtration efficiency in a quasi-continuous approximation. Also, we conduct numerical simulations of the deposition of respiratory droplets on a compact periodic array of cylindrical electrodes located at the nodes of a square lattice. The droplets with a radius of 10-20 μm pose the greatest threat in spreading the respiratory infections, and as we demonstrate, the proposed system is very effective in capturing droplets of this size, specifically, for a filter element with a width of about 5 mm, the filtration efficiency exceeds 90%.

Ensuring the normalization of the aero-ionic regime in production areas by means of ultrasonic air ionization

The results of studies on the normalization of the aeroionic regime in rooms under ultrasonic ionization of humidified air are presented. The increase in the concentration of negative aeroions under these conditions by the combined effect of the balloelectric effect and ultrasonic cavitation is substantiated. It has been established that when distilled water is used as a source of air ions under the action of a 10 W ultrasonic generator at a distance of 0.5 m, the concentration of negative air ions increases almost sixfold. At the same time, due to the joint effect of ultrasonic cavitation in the surface layer of water and the balloelectric effect, no generation of ozone and nitrogen oxides is caused. It is proved that with a decrease in the degree of water mineralization, the concentrations of negative and positive aeroions increase due to changes in the physicochemical properties of water and the resulting mechanochemical phenomena. The mechanism of formation of air ions in the air of industrial premises under the combined action of the balloelectric effect and ultrasound is proposed. It is substantiated that the quality of the air ionic composition of industrial premises air improves at a temperature of demineralized water of 20-25 °C and a directed air flow of 6 m/s towards the working area with the combined effect of ultrasound and balloelectric effect, which contributes to the improvement of sanitary and hygienic working conditions. The structure of an automated system for controlling the aeroionic regime of the working area of industrial premises with artificial ionization of humidified air using an aeroion generator and a ventilation system is proposed. This will allow monitoring and processing of information on technological, electrical and microclimatic parameters, adjusting, coordinating and jointly controlling the ventilation system devices and the ultrasonic generator of air ions.

Impact of Pulse Electric Field Stimulation on Negative Air Ion Release Capacity of Snake Plants

To investigate the effects of pulse electric field stimulation on the photosynthetic electron transport chain and negative air ion (NAI) release capacity of snake plants, the chlorophyll content, fluorescence induction kinetics curve (OJIP curve), chlorophyll fluorescence parameters, and NAI release concentration of snake plants kept under identical greenhouse conditions under different pulse electric field stimulations were compared and analyzed. The experimental results show that (1) after pulse electric field stimulation, the chlorophyll content in treatment group T1 (5 kv) and T2 (7 kv) of snake plants increased by 6.30% and 6.70%, respectively, with significant differences observed between the two treatment groups and the control group (CK). (2) In both treatment groups, the OJIP curve exhibited higher values for the inflection point (I) and peak (P) compared to the origin (O) and inflection point (J) values, with the rising trend in the I–P segment being more gentle than that of the O–J segment. Additionally, the J band was above 0, with the peak value in the T2 group being higher than that in the T1 group. (3) The chlorophyll fluorescence parameters showed fluctuating variations. Specifically, Fm, TRo/CSo, ETo/CSo, and DIo/CSo showed ascending trends in the treatment groups. Fv/Fo, Sm, and ABS/RC exhibited descending trends; Fv/Fm, Vj, ETo/RC, and φEo showed relatively minor changes. The PIabs displayed a decreasing trend. The PItotal in the CK was greater than that in the T1 and T2 groups. (4) After 4 h of pulse electric field stimulation, the NAI concentration increased by 87.60% in the T1 group and by 62.09% in the T2 group, compared to the same measurement taken at 3 h. Pulse electric field impacts the photosynthetic electron transport chain of snake plants, thereby influencing their NAI release capacity. This study aims to elucidate the physiological responses of the chloroplasts in snake plants to pulsed electric field stimulation and to lay the foundation for enhancing the plant’s release of negative air ion concentrations through physical and technological means.

The behaviour of charged particles (ions) during new particle formation events in urban Leipzig, Germany

Abstract. Air ions are electrically charged particles in air. They are ubiquitous in the natural environment and affect the Earth's radiation budget by accelerating the formation and growth of new aerosol particles. Despite this, few datasets exist exploring these effects in the urban environment. A neutral cluster and air ion spectrometer was deployed in Leipzig, Germany, to measure the number size distribution of charged particles from 0.8 to 42 nm, between 27 July and 25 August 2022. Following previous analyses, charged particles were classified into small (0.8–1.6 nm), intermediate (1.6–7.5 nm), and large (7.5–22 nm) fractions by mass diameter, and their mean concentrations (sum of positive and negative polarities) during the campaign were 405, 71.6, and 415 cm−3, respectively. The largest peaks in intermediate and large ions were explained by new particle formation (NPF), with intermediate ions correlating well with sulfuric acid dimer. Smaller morning and evening peaks were coincident with black carbon concentrations and attributed to primary emissions. NPF events, observed on 30 % of days, coincided with intense solar radiation and elevated sulfuric acid dimer. Small charged particles were primarily associated with radioactive decay and highest during the early hours, and they are unrelated to primary emissions or NPF. The apparent contributions of charged particles to 3 and 7.5 nm particle formation rates were 5.7 % and 12.7 %, respectively, with mean growth rates of 4.0 nm h−1 between 3–7.5 nm and 5.2 nm h−1 between 7.5 and 22 nm. The ratio of charged to total particle formation rates at 3 nm suggests a minor role for charged particles in NPF. We conclude that NPF is a primary source of > 3 nm ions in our data, with primary emissions being the major source in the absence of NPF.

The Combined Effects of the Thermal Environment and Air Quality at Recreation Places on the Physiology and Psychology of People in Urban Parks

Urban forests, crucial to urban ecosystems, are increasingly threatened by the challenges of urbanization, such as deteriorating thermal environments and declining air quality. Despite their recognized benefits to city dwellers’ quality of life, a systematic understanding of the impact of these environmental factors on public psychophysiological well-being in recreational sites is a notable gap in the literature. The objective of this research was to bridge this gap by examining the effects of the thermal environment and air quality in urban forests on the public’s perception, offering scientific evidence to inform environmental optimization and health management strategies for urban parks, essential for sustainable urban development and public health. Three urban parks in Fuzhou, Fujian Province, namely Fuzhou National Forest Park, Xihu Park, and Jinniushan Sports Park, were selected as research sites. Environmental monitoring and questionnaire surveys were conducted at 24 recreation places from October to December 2020, collecting temperature, humidity, and wind speed; the atmospheric composition includes PM2.5, PM10, negative oxygen ion, and psychophysiological data from the public. Multivariate statistical methods were employed to assess the environmental characteristics of different recreation places types and their impact on public health. The findings reveal that environmental factors explained 1.9% to 11.8% of the variation in physiological and psychological responses, mainly influenced by temperature, wind speed, and negative oxygen ions. Forests and waterfront recreation places significantly outperform canopy and open recreation places in promoting mental invigoration, stress relief, emotional tranquility, and attention restoration. Environmental monitoring results indicate that favorable meteorological conditions and good air quality are crucial for enhancing the service functions of recreation places. Notably, the positive correlation between a negative air ion concentration and psychological well-being provides a novel perspective on understanding the health benefits of urban forests. The thermal environment and air quality of urban recreation places exert a significant influence on the psychophysiological status of the public. Increasing green coverage, improving water body environments, and rationally planning recreation places layout are of great theoretical and practical significance for enhancing the environmental quality and service functions of urban forests.

PM1.0 removal enhancement in cooperated electric-ionic field by negative air ions carbon fiber electrode

The study focuses on improving the removal efficiency of submicron particles using negative air ions (NAIs), which are challenging to remove. To enhance this efficiency, cascaded carbon fiber tubular (CFT) chargers were designed to boost particle charging. Through experiments and numerical simulations, the chargers’ enhancement mechanisms, cooperation effects, and overall performance were evaluated. The optimal configuration for the CFT charger was identified as a gap distance (d = 2.0 r0) and grounded electrode length (L0 = 4πr03) that ensures high collection efficiency (96.7 % for 0.5 μm particles at 4 m/s) and ultra-low ozone generation (7.25 ppb). The study found that while the average electric field strength (E¯) and ion density significantly influence charging, an unusual improvement in collection efficiency was observed the charger with d = 2.0 r0 at u = 3 m/s, likely due to the potential predominance of the maximum electric field strength (Emax) at relative higher velocity. Besides, the CFT charger demonstrated balanced performance compared to other reported works, although higher relative humidity (80 ± 5 % RH) inhibits removal efficiency, which can be mitigated by reducing gas velocity.

The Quality of the Air we Breathe is Getting Worse, the Dust can be Dangerous: In what way?

Based on the observation that air quality measuring devices have shown increased levels of dust pollution in recent years, we carried out an investigation over two years. This confirmed the assumption of increasing air pollution: a significant increase in the parts per million of dust particles. By analysing the filter contents of an air ionizer, we were able to find various pollutants: Arsenic, aluminum, titanium, fluorides, barium as well as mold spores. The causes can be assumed to be Geoengineering, Solar Radiation Management and Stratospheric Aerosol Injection. Air purification devices are therefore becoming increasingly important.

Seamless Hourly Estimation of Negative Air Ion Concentrations: Integrating Hybrid Stacked Machine Learning Models With Kriging Spatiotemporal Augmentation

AbstractNegative Air Ions (NAIs), essential for environmental and human health, facilitate air purification and offer antimicrobial benefits. Our study achieves hourly estimations of NAIs using a machine learning framework, developed from a multi‐layer selection pipeline of over 200 variables, to identify the key determinants critical for adapting to high‐resolution NAIs dynamics. Addressing site sparsity and NAIs volatility, we introduced a hybrid stacking incorporating pseudo sites generated from Kriging Spatiotemporal Augmentation (KSTA) to mitigate spatial overfitting. Our approach, validated in Zhejiang, China, demonstrates exceptional accuracy, achieving R2 values of 0.90 (sample‐based), 0.85 (temporal‐based), and 0.79 (site‐based). This work not only sheds light on NAIs behavior in relation to diurnal shifts, land use, and environmental events, but also integrates a health grading system, enhancing public health strategies through precise air quality assessment.

Combating Pathogens Using Carbon-Fiber Ionizers (CFIs) for Air Purification: A Narrative Review

Airborne pathogens, though a minor fraction of airborne particles, can cause infections, intoxications, or allergic reactions through respiration, dermal contact, or ingestion. The SARS-CoV-2 pandemic has underscored the significance of mitigating airborne microbial threats. Traditional air ionization methods, such as dielectric barrier discharge and metal tip corona discharge, produce ozone, a reactive and potentially harmful byproduct. However, carbon-fiber ionizers (CFIs) generate high concentrations of ions with minimal ozone production, making them a safer alternative. Operating at voltages below 5 kV, CFIs are more efficient than their metallic counterparts. This review focuses on the antimicrobial efficacy of CFIs, which produce unipolar ions that can disrupt microbial membranes, leading to cell death. Compared to ultraviolet light sterilization, CFIs are cost-effective and suitable for small spaces. The literature review highlights the need for comprehensive studies to evaluate the real-world application and effectiveness of CFIs. Many existing studies are limited by small-scale testing and insufficient data reporting, complicating comparative analyses. Our work aims to provide a detailed perspective on CFIs, examining their impact on various microorganisms, ion efficacy, ionization outcomes, and ozone generation levels. By addressing these aspects, the review seeks to offer an updated understanding of CFIs’ antimicrobial capabilities and to identify limitations in current research, paving the way for more informed and effective air purification strategies.

Formation of ions under the action of cosmic rays in humid air

The processes of ion formation in humid tropospheric air under the action of cosmic rays are considered. In this case, positive and negative cluster ions appear. For this analysis, a kinetic model was developed that includes 55 components and 161 reactions. The calculation was carried out using the KINET software package. It is shown that the ionization of air by cosmic rays at altitudes of 5–35 km leads to the formation of plasma consisting mainly of NH4+⋅NH3⋅H2O, H+⋅(H2O)4 and O2−⋅(H2O)2 ions. The maximum concentrations of ions under conditions of minimum magnetic rigidity are observed at altitudes from 10 to 18 km. These results differ sharply from the calculation results obtained for the dry air model.

Impact of Negative Air Ions on Hematological and Hormonal Parameters in Cerebral Palsy

Impact of Negative Air Ions on Hematological and Hormonal Parameters in Cerebral Palsy

Earthquake Precursors: The Physics, Identification, and Application

The paper presents the author’s vision of the problem of earthquake hazards from the physical point of view. The first part is concerned with the processes of precursor’s generation. These processes are a part of the complex system of the lithosphere–atmosphere–ionosphere–magnetosphere coupling, which is characteristic of many other natural phenomena, where air ionization, atmospheric thermodynamic instability, and the Global Electric Circuit are involved in the processes of the geosphere’s interaction. The second part of the paper is concentrated on the reliable precursor’s identification. The specific features helping to identify precursors are separated into two groups: the absolute signatures such as the precursor’s locality or equatorial anomaly crests generation in conditions of absence of natural east-directed electric field and the conditional signatures due to the physical uniqueness mechanism of their generation, or necessity of the presence of additional precursors as multiple consequences of air ionization demonstrating the precursor’s synergy. The last part of the paper is devoted to the possible practical applications of the described precursors for purposes of the short-term earthquake forecast. A change in the paradigm of the earthquake forecast is proposed. The problem should be placed into the same category as weather forecasting or space weather forecasting.

Ionic liquid–electrode interface: Classification of ions, saturation of layers, and structure-determined potentials

Progress in electrochemical applications of ionic liquids builds on an understanding of electrical double layer. This computational study focuses on structure-determined quantities – maximum packing density, potentials, and capacitances – evaluated using a one-electrode electrical double layer model. Interfaces of the 40 studied ions are grouped into four distinct classes according to their characteristic packing at the model surface. The simulations suggest that the exact screening by a monolayer of counter-ions (preceding the crowding of ions) is unlikely for ions in known air- and water-stable ionic liquids within their electrochemical stability window. This work discusses how the assessed structure-determined quantities can guide the experimental tuning of (electro/mechano)chemical properties and characterize the structure of ionic liquid–electrode interfaces.