Methods for Source Characterization of Organic Air Pollutants

1990 ◽  
Vol 6 (5) ◽  
pp. 67-80
Author(s):  
H. J. Th. Bloemen ◽  
J. J. G. Kliest
Keyword(s):  
Air Pollution ◽  
Organic Compounds ◽  
Air Pollutants ◽  
Source Characterization ◽  
Mathematical Methods ◽  
Remedial Actions ◽  
Exposure Evaluation

Organic compounds are becoming increasingly more of interest as air pollutants, indoor as well as outdoor. Sources emitting such compounds are numerous and of various origin. For toxicological and epidemiological examination and for deciding on remedial actions information is required on the occurrences of compounds as well as on the emitting sources. For this purpose a number of investigations have been carried out with only limited success. To increase the quality of the description of air pollution related to complaints of dwellers and to exposure evaluation analytical and mathematical methods have tested in our laboratory. Analytical methods for the determination of different groups of organic compounds and mathematical methods for defining minimum sampling strategies and for the characterization of sources are discussed and illustrated with applications dealt with in the passed years. It is concluded that the application of a combination of these methods offers a manner to better describe and understand air pollution with organic compounds.

scholarly journals Contribution of Local and Transboundary Air Pollution to the Urban Air Quality of Fukuoka, Japan

Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 431
Author(s):  
Ayako Yoshino ◽  
Akinori Takami ◽  
Keiichiro Hara ◽  
Chiharu Nishita-Hara ◽  
Masahiko Hayashi ◽  
...  
Keyword(s):  
Air Pollution ◽  
Air Quality ◽  
Urban Areas ◽  
Air Pollutants ◽  
Regional Scale ◽  
Gaseous Species ◽  
Transboundary Air Pollution ◽  
Local Air Pollution ◽  
The City

Transboundary air pollution (TAP) and local air pollution (LAP) influence the air quality of urban areas. Fukuoka, located on the west side of Japan and affected by TAP from the Asian continent, is a unique example for understanding the contribution of LAP and TAP. Gaseous species and particulate matter (PM) were measured for approximately three weeks in Fukuoka in the winter of 2018. We classified two distinctive periods, LAP and TAP, based on wind speed. The classification was supported by variations in the concentration of gaseous species and by backward trajectories. Most air pollutants, including NOx and PM, were high in the LAP period and low in the TAP period. However, ozone was the exception. Therefore, our findings suggest that reducing local emissions is necessary. Ozone was higher in the TAP period, and the variation in ozone concentration was relatively small, indicating that ozone was produced outside of the city and transported to Fukuoka. Thus, air pollutants must also be reduced at a regional scale, including in China.

scholarly journals Cause-and-effect relationships between air pollution and health conditions in population

2020 ◽  
Vol 5 (4) ◽  
pp. 230-234
Author(s):  
I. I. Berezin ◽  
Yu. Yu. Eliseev ◽  
A. K. Sergeev
Keyword(s):  
Air Pollution ◽  
Allergic Rhinitis ◽  
Bronchial Asthma ◽  
Respiratory System ◽  
Air Pollutants ◽  
Preventive Measures ◽  
Industrial City ◽  
Cause And Effect ◽  
The Impact

Objectives to reveal cause-and-effect relationships in the system "air pollution morbidity of the population" in a large industrial city. Material and methods.The dynamics of the pollutants concentration, such as formaldehyde and benzopyrene, through the period of 20152017 was analyzed in relation to the indicators of the morbidity of the respiratory system in the population of Samara. In particular, the study focused on the ratio of allergic rhinitis and asthma cases and the concentration of the formaldehyde and benzopyrene. Results.The incidence of respiratory diseases and the general morbidity increased both among children (by 46.7%) and adults (by 11.4%). There was the causal correlation between the effect of benzopyrene on the development of allergic rhinitis and bronchial asthma in children(r = 0.57 and r = 0.76) and in adults (r = 0.45 and r = 0.51) in Samara. The significant differences between the level of the pollutants and the frequency of the respiratory system diseases were registered in children and adults in different areas of Samara. Discussion.As a result of the increase of the maximum allowable concentration (MAC) of formaldehyde in atmospheric air, this pollutant has now ceased to be a priority. The revealed negative correlations point to the absence of an adverse effect of formaldehyde on the development of allergic rhinitis and bronchial asthma in both children and adults in Samara. Conclusion.According to the results of the study, the preventive measures aimed at reducing the impact of main air pollutants on the health of children and adults in Samara were suggested. Their implementation is possible by the immediate informing of the executive authorities to ensure they can make timely management decisions to improve the quality of the environment.

scholarly journals Effects of gas–wall interactions on measurements of semivolatile compounds and small polar molecules

2019 ◽  
Vol 12 (6) ◽  
pp. 3137-3149 ◽  
Author(s):  
Xiaoxi Liu ◽  
Benjamin Deming ◽  
Demetrios Pagonis ◽  
Douglas A. Day ◽  
Brett B. Palm ◽  
...  
Keyword(s):  
Organic Compounds ◽  
Transmission Efficiency ◽  
Polar Molecules ◽  
Ionization Mass ◽  
Atmospheric Measurements ◽  
Wide Range ◽  
Teflon Tubing ◽  
Gas Interactions

Abstract. Recent work has quantified the delay times in measurements of volatile organic compounds (VOCs) caused by the partitioning between the gas phase and the surfaces of the inlet tubing and instrument itself. In this study we quantify wall partitioning effects on time responses and transmission of multifunctional, semivolatile, and intermediate-volatility organic compounds (S/IVOCs) with saturation concentrations (C∗) between 100 and 104 µg m−3. The instrument delays of several chemical ionization mass spectrometer (CIMS) instruments increase with decreasing C∗, ranging from seconds to tens of minutes, except for the NO3- CIMS where it is always on the order of seconds. Six different tubing materials were tested. Teflon, including PFA, FEP, and conductive PFA, performs better than metals and Nafion in terms of both delay time and transmission efficiency. Analogous to instrument responses, tubing delays increase as C∗ decreases, from less than a minute to >100 min. The delays caused by Teflon tubing vs. C∗ can be modeled using the simple chromatography model of Pagonis et al. (2017). The model can be used to estimate the equivalent absorbing mass concentration (Cw) of each material, and to estimate delays under different flow rates and tubing dimensions. We also include time delay measurements from a series of small polar organic and inorganic analytes in PFA tubing measured by CIMS. Small polar molecules behave differently than larger organic ones, with their delays being predicted by their Henry's law constants instead of their C∗, suggesting the dominance of partitioning to small amounts of water on sampling surfaces as a result of their polarity and acidity properties. PFA tubing has the best performance for gas-only sampling, while conductive PFA appears very promising for sampling S/IVOCs and particles simultaneously. The observed delays and low transmission both affect the quality of gas quantification, especially when no direct calibration is available. Improvements in sampling and instrument response are needed for fast atmospheric measurements of a wide range of S/IVOCs (e.g., by aircraft or for eddy covariance). These methods and results are also useful for more general characterization of surface–gas interactions.

Review: Selected indicators of the quality of thermal processed milk / Revisión: Indicadores seleccionados para el control de calidad de la leche tratada térmicamente

1999 ◽  
Vol 5 (2) ◽  
pp. 121-137 ◽  
Author(s):  
R. López-Fandiño ◽  
A. Olano
Keyword(s):  
Shelf Life ◽  
Thermal Process ◽  
Whey Proteins ◽  
Lipid Degradation ◽  
Uht Milk ◽  
Heat Stable ◽  
New Compounds

Selected indicators of the quality of processed milk are reviewed in three sections: indices of heat treatment, detection of adulterations and assessment of shelf life. The characterization of the thermal process to which milk was submitted can be achieved by measuring either the formation of new compounds (lactulose, furosine) or the degradation of thermolabile constituents (enzymes, whey proteins). The presence of certain compounds may indicate fraudulent additions committed for eco nomic reasons. Finally, residual or reactivated heat stable enzymes may cause serious storage defects in UHT milk and, therefore, the proteolytic and lipolytic activities and the degree of protein and lipid degradation are useful predictors of the shelf life. Different analytical methods for the determination of the selected quality indicators are also summarized.

scholarly journals Effects of Gas-Wall Interactions on Measurements of Semivolatile Compounds and Small Polar Molecules

2019 ◽  
Author(s):  
Xiaoxi Liu ◽  
Benjamin Deming ◽  
Demetrios Pagonis ◽  
Douglas A. Day ◽  
Brett B. Palm ◽  
...  
Keyword(s):  
Organic Compounds ◽  
Transmission Efficiency ◽  
Polar Molecules ◽  
Ionization Mass ◽  
Atmospheric Measurements ◽  
Wide Range ◽  
Teflon Tubing ◽  
Gas Interactions

Abstract. Recent work has quantified the delay times in measurements of volatile organic compounds (VOCs) caused by the partitioning between the gas phase and the surfaces of the inlet tubing and instrument itself. In this study we quantify wall partitioning effects on time responses and transmission of multi-functional, semivolatile and intermediate-volatility organic compounds (S/IVOCs) with saturation concentrations (C*) between 100 and 104 µg m−3. The instrument delays of several chemical ionization mass spectrometer (CIMS) instruments increase with decreasing C*, ranging from seconds to tens of minutes, except for the NO3−-CIMS where it is always on the order of seconds. Six different tubing materials were tested. Teflon, including PFA, FEP, and conductive PFA, performs better than metals and Nafion in terms of both delay time and transmission efficiency. Analogous to instrument responses, tubing delays increase as C* decreases, from less than a minute to > 100 min. The delays caused by Teflon tubing vs. C* can be modeled using the simple chromatography model of Pagonis et al. (2017). The model can be used to estimate the equivalent absorbing mass concentration (Cw) of each material, and to estimate delays under different flow rates and tubing dimensions. We also include time delay measurements from a series of small polar organic and inorganic analytes in PFA tubing measured by CIMS. Small polar molecules behave differently than larger organic ones, with their delays being predicted by their Henry’s law constants instead of their C*, suggesting the dominance of partitioning to small amounts of water on sampling surfaces as a result of their polarity and acidity properties. PFA tubing has the best performance for gas-only sampling, while conductive PFA appears very promising for sampling S/IVOCs and particles simultaneously. The observed delays and low transmission both affect the quality of gas quantification, especially when no direct calibration is available. Improvements in sampling and instrument response are needed for fast atmospheric measurements of a wide range of S/IVOCs (e.g., by aircraft or for eddy covariance). These methods and results are also useful for more general characterization of surface/gas interactions.

Characterization of Medicinal Plants Sorting Process by Planar Sieving through Mechanical Oscillations Analysis

2015 ◽  
Vol 801 ◽  
pp. 213-218
Author(s):  
Augustina Pruteanu ◽  
Mihai Matache ◽  
Ladislau David ◽  
Catalin Persu ◽  
M. Duţu ◽  
...  
Keyword(s):  
Technological Parameters ◽  
Mechanical Oscillations ◽  
Separation Degree ◽  
Sorting Process ◽  
Working Set ◽  
Set Up ◽  
Optimum Working

The mechanical sorting process of granular and vegetal materials is a complex technological process influenced by a series of factors from which we remind: mechanical vibratory motion, geometrical measures of the sorting equipment and technological factors. Based on correlations between the presented elements one can establish the technological parameters of the sorting process so that to realize a quality separation.In the paper we present a method for determination of mechanical oscillations influence on the quality of the sorting process with planar sieves. The experiments performed on a dimensional sorter with planar sieves aimed at identification of an optimum working set-up in terms of frequency and amplitude of the sorter’s vibrators, for a quality separation degree.

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