scholarly journals Effect of Environmental Factors on Air Ion Concentration

2015 ◽  
Vol 2 ◽  
pp. 274
Author(s):  
Andris Skromulis ◽  
Juris Breidaks
Keyword(s):  
Environmental Factors ◽  
Ion Concentration ◽  
Physical Parameters ◽  
Urban Air ◽  
Regression Equations ◽  
Air Ions ◽  
Atmospheric Air ◽  
Ion Concentrations ◽  
Air Ion Concentration ◽  
Ion Size

<p class="R-AbstractKeywords"><span lang="EN-US">The paper discusses and analyzes the effect of environmental factors on ion concentrations in urban air. Statistically mathematical method was used to analyze the measurements of air ion concentration collected in a period of several months, with ion size ranging from 0.75 to 36.6 nm. As environmental factors related to air ions, the following chemical and physical parameters of the atmospheric air were analyzed: CO, NO, NO<sub>2</sub>, NO<sub>x</sub>, SO<sub>2</sub>, O<sub>3</sub>, PM10, PM2.5, temperature, relative humidity, wind speed and direction. When analyzing data in this combination, there is often a problem of multicollinearity between air chemical and physical parameters. This paper addresses this problem by using the component regression. Regression equations were elaborated to understand the dependence of concentrations of various classes of positive and negative air ions on chemical and physical parameters of the air.</span></p>

scholarly journals Variation and balance of positive air ion concentrations in a boreal forest

2008 ◽  
Vol 8 (3) ◽  
pp. 655-675 ◽  
Author(s):  
U. Hõrrak ◽  
P. P. Aalto ◽  
J. Salm ◽  
K. Komsaare ◽  
H. Tammet ◽  
...  
Keyword(s):  
Steady State ◽  
Boreal Forest ◽  
Correlation Coefficient ◽  
Aerosol Particles ◽  
Coniferous Forest ◽  
Ionization Rate ◽  
Ion Concentration ◽  
Air Ions ◽  
Ion Concentrations ◽  
Charged Aerosol

Abstract. Air ions are characterized on the basis of measurements carried out in a boreal forest at the Hyytiälä SMEAR station, Finland, during the BIOFOR III campaign in spring 1999. The air ions were discriminated as small ions (charged molecular aggregates of the diameter of less than 2.5 nm), intermediate ions (charged aerosol particles of the diameter of 2.5–8 nm), and large ions (charged aerosol particles of the diameter of 8–20 nm). Statistical characteristics of the ion concentrations and the parameters of ion balance in the atmosphere are presented separately for the nucleation event days and non-event days. In the steady state, the ionization rate is balanced with the loss of small ions, which is expressed as the product of the small ion concentration and the ion sink rate. The widely known sinks of small ions are the recombination with small ions of opposite polarity and attachment to aerosol particles. The dependence of small ion concentration on the concentration of aerosol particles was investigated applying a model of the bipolar diffusion charging of particles by small ions. When the periods of relative humidity above 95% and wind speed less than 0.6 m s−1 were excluded, then the small ion concentration and the theoretically calculated small ion sink rate were closely negatively correlated (correlation coefficient −87%). However, an extra ion loss term of the same magnitude as the ion loss onto aerosol particles is needed for a quantitative explanation of the observations. This term is presumably due to the small ion deposition on coniferous forest. The hygroscopic growth correction of the measured aerosol particle size distributions was also found to be necessary for the proper estimation of the ion sink rate. In the case of nucleation burst events, the concentration of small positive ions followed the general balance equation, no extra ion loss in addition to the deposition on coniferous forest was detected, and the hypothesis of the conversion of ions into particles in the process of ion-induced nucleation was not proved. The estimated average ionization rate of the air at the Hyytiälä station in early spring, when the ground was partly covered with snow, was about 6 ion pairs cm−3 s−1. The study of the charging state of nanometer aerosol particles (diameter 2.5–8 nm) in the atmosphere revealed a strong correlation (correlation coefficient 88%) between the concentrations of particles neutralized in the aerosol spectrometer and naturally positively charged particles (air ions) during nucleation bursts. The charged fraction of particles varied from 3% to 6% in accordance with the hypothesis that the particles are quasi-steady state charged.

scholarly journals How do air ions reflect variations in ionising radiation in the lower atmosphere in a boreal forest?

2016 ◽  
Vol 16 (22) ◽  
pp. 14297-14315 ◽  
Author(s):  
Xuemeng Chen ◽  
Veli-Matti Kerminen ◽  
Jussi Paatero ◽  
Pauli Paasonen ◽  
Hanna E. Manninen ◽  
...  
Keyword(s):  
Gamma Radiation ◽  
Boreal Forest ◽  
Ionising Radiation ◽  
Ion Concentration ◽  
Lower Atmosphere ◽  
Air Ions ◽  
Long Distance ◽  
Ion Concentrations ◽  
Depth Analysis ◽  
Ion Production

Abstract. Most of the ion production in the atmosphere is attributed to ionising radiation. In the lower atmosphere, ionising radiation consists mainly of the decay emissions of radon and its progeny, gamma radiation of the terrestrial origin as well as photons and elementary particles of cosmic radiation. These types of radiation produce ion pairs via the ionisation of nitrogen and oxygen as well as trace species in the atmosphere, the rate of which is defined as the ionising capacity. Larger air ions are produced out of the initial charge carriers by processes such as clustering or attachment to pre-existing aerosol particles. This study aimed (1) to identify the key factors responsible for the variability in ionising radiation and in the observed air ion concentrations, (2) to reveal the linkage between them and (3) to provide an in-depth analysis into the effects of ionising radiation on air ion formation, based on measurement data collected during 2003–2006 from a boreal forest site in southern Finland. In general, gamma radiation dominated the ion production in the lower atmosphere. Variations in the ionising capacity came from mixing layer dynamics, soil type and moisture content, meteorological conditions, long-distance transportation, snow cover attenuation and precipitation. Slightly similar diurnal patterns to variations in the ionising capacity were observed in air ion concentrations of the cluster size (0.8–1.7 nm in mobility diameters). However, features observed in the 0.8–1 nm ion concentration were in good connection to variations of the ionising capacity. Further, by carefully constraining perturbing variables, a strong dependency of the cluster ion concentration on the ionising capacity was identified, proving the functionality of ionising radiation in air ion production in the lower atmosphere. This relationship, however, was only clearly observed on new particle formation (NPF) days, possibly indicating that charges after being born underwent different processes on NPF days and non-event days and also that the transformation of newly formed charges to cluster ions occurred in a shorter timescale on NPF days than on non-event days.

scholarly journals Impact of Microclimate and Indoor Plants on Air Ion Concentration

2015 ◽  
Vol 1 ◽  
pp. 66
Author(s):  
Natalia Sinicina ◽  
Andris Skromulis ◽  
Andris Martinovs
Keyword(s):  
Volatile Compounds ◽  
Human Health ◽  
Indoor Air ◽  
Ion Concentration ◽  
Air Ions ◽  
Indoor Plants ◽  
Ion Absorption ◽  
Air Ion Concentration

Saturation of air ions is essentially important for all living beings, especially for human health. Existing sanitary norms provide that concentration of small ions has to be in range of 400-50000 ions cm-3 and unipolarity coefficient 0.4 ≤ K ≤ 1.0. Many species of indoor plants emit organic volatile compounds and air ions, therefore they could be used for improving the quality of indoor air. The results show that ionization level of indoor air is significantly insufficient and selected species of indoor plants are not able to improve it. They serve rather as supplementary surfaces for ion absorption. Possible interaction between microclimate, ion concentration and indoor plants in different times of the day is analyzed.

Heat Power Determination of Dv-290 Refrigerator’s Evaporator on the Basis of Thermodynamic Parameters of Inlet Air / Określenie Mocy Cieplnej Parownika Chłodziarki Dv-290 Na Podstawie Parametrów Termodynamicznych Powietrza Wlotowego

2012 ◽  
Vol 57 (4) ◽  
pp. 911-920
Author(s):  
Bernard Nowak ◽  
Zbigniew Kuczera
Keyword(s):  
Thermodynamic Parameters ◽  
Thermal Power ◽  
Correlation Coefficients ◽  
Specific Humidity ◽  
Physical Parameters ◽  
Air Cooling ◽  
Regression Equations ◽  
Evaporation And Condensation ◽  
Before And After ◽  
The Given

Abstract The present paper introduces a method for calculating the thermal power of DV-290 mining air cooler’s evaporator. The power usually differs from the nominal power given by the manufacturer. The thermodynamic parameters of cooled air are not obtained as a result of in situ measurements, but in indirect manner that is by determining the evaporation and condensation’s pressure values of R407C refrigerant. The pressure dependencies formulated as a function of air enthalpy at the evaporator’s inlet were obtained using calculations of a computer program which solves the system of equations describing heat and mass transfer in the refrigerator’s compressor on the basis of previous measurements of air performed before and after its cooling. The obtained dependencies are demonstrated in a graphical (fig. 2 and fig. 3) and analytical (the regression equations (19) and (20)) manner, the values of correlation coefficients are also presented. For the known evaporation and condensation pressure values of the refrigerant, and thus for its basic physical parameters the complete thermal power of the evaporator was determined, that is its: air cooling overt power, dehumidification occult power, temperature, relative humidity and specific humidity of air after its cooling. In addition, using the mentioned method, the capacity of DV-290 refrigerator’s evaporator is provided for the given thermodynamic parameters of air before cooling, along with air thermodynamic parameters after cooling.

Thermal stability of ribosomes from a thermophilic and a mesophilic fungus

1973 ◽  
Vol 19 (6) ◽  
pp. 761-763 ◽  
Author(s):  
H. M. Miller ◽  
M. G. Shepherd
Keyword(s):  
Thermal Stability ◽  
Ion Concentration ◽  
Magnesium Ion ◽  
Penicillium Notatum ◽  
Ribosomal Subunits ◽  
Ion Concentrations ◽  
Thermal Stability Of

Ribosomes and ribosomal subunits from the thermophile Penicillium duponti were found to be more thermostable than the corresponding particles from the mesophile Penicillium notatum. The thermostability of the ribosomes from both organisms was dependent on magnesium ion concentration. The dissociation of the 80-S ribosomes into 60-S and 40-S subunits occurred at higher magnesium ion concentrations for the mesophile than the thermophile.

scholarly journals From ionising radiation to air ion formation in the lower atmosphere

2016 ◽  
Author(s):  
Xuemeng Chen ◽  
Veli-Matti Kerminen ◽  
Jussi Paatero ◽  
Pauli Paasonen ◽  
Hanna E. Manninen ◽  
...  
Keyword(s):  
Gamma Radiation ◽  
Ionising Radiation ◽  
Ion Concentration ◽  
Lower Atmosphere ◽  
Forest Site ◽  
Long Distance ◽  
Ion Concentrations ◽  
Ion Formation ◽  
Depth Analysis ◽  
Ion Production

Abstract. Most of the ion production in the atmosphere is attributed to ionising radiation. In the lower atmosphere, ionising radiation consists mainly of the decay emissions of radon and its progeny, gamma radiation of the terrestrial origin as well as photons and elementary particles of cosmic radiation. These types of radiation produce ion pairs via the ionisation of nitrogen and oxygen as well as trace species in the atmosphere, the rate of which is defined as the ionising capacity. Larger air ions are produced out of the initial charge carriers by processes, such as clustering or attachment to pre-existing aerosol particles. This study aimed 1) to identify the key factors responsible for the variability in ionising radiation and in the observed air ion concentrations, 2) to reveal the linkage between them, and 3) to provide an in-depth analysis into the effects of ionising radiation on air ion formation, based on measurement data collected during 2003–2006 from a boreal forest site in southern Finland. In general, gamma radiation dominated the ion production in the lower atmosphere. Variations in the ionising capacity came from mixing layer dynamics, soil type and moisture content, meteorological conditions, long-distance transportation, snow cover attenuation and precipitation. Similar diurnal patterns to variations in the ionising capacity were observed in air ion concentrations of the cluster size (0.8–1.7 nm in mobility diameters). Clear promotion effects of the ionising radiation on air ion production were demonstrated. Typically, features observed in the 0.8–1 nm ion concentration were in connection to variations of the ionising capacity. Further by carefully constraining perturbing variables, a clear relationship was also identifiable between the cluster ion concentration and the ionising capacity, proving the functionality of ionising radiation in air ion production in the lower atmosphere.

scholarly journals Characterization of air ions in boreal forest air during BIOFOR III campaign

2005 ◽  
Vol 5 (3) ◽  
pp. 2749-2790 ◽  
Author(s):  
U. Hõrrak ◽  
P. P. Aalto ◽  
J. Salm ◽  
J. M. Mäkelä ◽  
L. Laakso ◽  
...  
Keyword(s):  
Boreal Forest ◽  
Correlation Coefficient ◽  
Aerosol Particles ◽  
Ion Pairs ◽  
Ion Concentration ◽  
Cluster Ions ◽  
Statistical Characteristics ◽  
Nucleation Event ◽  
Air Ions ◽  
20 Nm

Abstract. The behavior of the concentration of positive small (or cluster) air ions and naturally charged nanometer aerosol particles (aerosol ions) has been studied on the basis of measurements carried out in a boreal forest at the Hyytiälä SMEAR station, Finland, during the BIOFOR III campaign in spring 1999. Statistical characteristics of the concentrations of cluster ions, two classes of aerosol ions of the sizes of 2.5–8 nm and 8–ca 20 nm and the quantities that determine the balance of small ions in the atmosphere have been given for the nucleation event days and non-event days. The dependence of small ion concentration on the ion loss (sink) due to aerosol particles was investigated applying a model of bipolar diffusion charging of particles by small ions. The small ion concentration and the ion sink were closely correlated (correlation coefficient 87%) when the fog events and the hours of high relative humidity (above 97%), as well as nocturnal calms and weak wind (wind speed<0.6 m s-1 had been excluded. In the case of nucleation burst events, variations in the concentration of small positive ions were in accordance with the changes caused by the ion sink due to aerosols; no clear indication of positive ion depletion by ion-induced nucleation was found. The estimated average ionization rate of air at the Hyytiälä station in early spring, when the ground was partly covered with snow, was about 4.8 ion pairs cm-3 s-1. The study of the charging state of nanometer aerosol particles (2.5–8 nm) revealed a strong correlation (correlation coefficient 88%) between the concentrations of particles and their charged fraction (positive air ions) during nucleation bursts. The estimated charged fraction of particles, which varied from 3% to 6% considering various nucleation event days, confirms that these particles are almost quasi-steady state charged. Also the particles and air ions in the size range of 8–ca 20 nm showed a good qualitative consistency; the correlation coefficient was 92%.

scholarly journals Measurements and correlations between several atmospheric parameters

2008 ◽  
Vol 6 (1) ◽  
pp. 99-104 ◽  
Author(s):  
Predrag Kolarz ◽  
Dusan Filipovic
Keyword(s):  
Relative Humidity ◽  
Inverse Correlation ◽  
Weather Conditions ◽  
Atmospheric Parameters ◽  
Air Ions ◽  
Ion Concentrations ◽  
Humidity Measurements ◽  
A Site ◽  
Made In ◽  
Strong Inverse Correlation

Diurnal atmospheric air-ion concentrations have been investigated at a site where synchronous aerosol, ozone, temperature and relative humidity measurements were also made. Air-ions, temperature and relative humidity were measured with Gerdien type Cylindrical Detector of Air-Ions (CDI-06) made in the Institute of Physics, Belgrade. Ozone and aerosols were measured with commercial instruments owned by the Institute of Public Health, Belgrade. Typical daily variations of the measured parameters were analyzed and showed that air-ions of both signs and ozone are positively correlated, while aerosols show strong inverse correlation with air-ions. Also, concentrations of air-ions and ozone are decreasing with temperature while aerosol concentration and humidity are increasing. These processes could be explained concerning properties of the specified parameters, measuring place properties and weather conditions.

scholarly journals Characterization of positive air ions in boreal forest air at the Hyytiälä SMEAR station

2007 ◽  
Vol 7 (4) ◽  
pp. 9465-9517 ◽  
Author(s):  
U. Hõrrak ◽  
P. P. Aalto ◽  
J. Salm ◽  
K. Komsaare ◽  
H. Tammet ◽  
...  
Keyword(s):  
Boreal Forest ◽  
Correlation Coefficient ◽  
Aerosol Particles ◽  
Ion Pairs ◽  
Coniferous Forest ◽  
Ion Concentration ◽  
Statistical Characteristics ◽  
Nucleation Event ◽  
Air Ions ◽  
20 Nm

Abstract. The behavior of the concentration of positive small (or cluster) air ions and naturally charged nanometer aerosol particles (aerosol ions) has been studied on the basis of measurements carried out in a boreal forest at the Hyytiälä SMEAR station, Finland, during the BIOFOR III campaign in spring 1999. Statistical characteristics of the concentrations of cluster ions, two classes of aerosol ions of the sizes of 2.5–8 nm and 8–ca. 20 nm and the quantities that determine the balance of small ions in the atmosphere have been given for the nucleation event days and non-event days. The dependence of small ion concentration on the ion loss (sink) due to aerosol particles was investigated applying a model of bipolar diffusion charging of particles by small ions. The small ion concentration and the ion sink were closely correlated (correlation coefficient –87%) when the fog events and the hours of high relative humidity (above 95%), as well as nocturnal calms and weak wind (wind speed <0.6 m s−1) had been excluded. However, an extra ion loss term presumably due to small ion deposition on coniferous forest with a magnitude equal to the average ion loss to pre-existing particles is needed to explain the observations. Also the hygroscopic growth correction of measured aerosol particle size distributions was found to be necessary for proper estimation of the ion sink. In the case of nucleation burst events, variations in the concentration of small positive ions were in accordance with the changes caused by the ion sink due to aerosols; no clear indication of positive ion depletion by ion-induced nucleation was found. The estimated average ionization rate of the air at the Hyytiälä station in early spring, when the ground was partly covered with snow, was about 6 ion pairs cm−3 s−1. The study of the charging state of nanometer aerosol particles (2.5–8 nm) revealed a strong correlation (correlation coefficient 88%) between the concentrations of particles and positively charged particles (positive air ions) during nucleation bursts. The estimated charged fraction of particles, which varied from 3% to 6% considering various nucleation event days, confirms that these particles are almost quasi-steady state charged. Also the particles and air ions in the size range of 8–ca. 20 nm showed a good qualitative consistency; the correlation coefficient was 92%.

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