scholarly journals Studies on photochemical reaction of air pollutants. X. Identification of nitrophenols in suspended particulates.

1983 ◽  
Vol 31 (3) ◽  
pp. 1047-1051 ◽  
Author(s):  
KAZUHIRO NOJIMA ◽  
AKIHIRO KAWAGUCHI ◽  
TAKESHI OHYA ◽  
SABURO KANNO ◽  
MASAAKI HIROBE
Keyword(s):  
Air Pollutants ◽  
Photochemical Reaction ◽  
Suspended Particulates

scholarly journals Pollutants and climatic conditions related to the formation of photochemical oxidants

2021 ◽  
Vol 5 (2) ◽  
pp. 001-005
Author(s):  
Shigeru Suna
Keyword(s):  
Economic Activity ◽  
Air Pollutants ◽  
Photochemical Reaction ◽  
Linear Regression Analysis ◽  
Climatic Conditions ◽  
Photochemical Reactions ◽  
Stepwise Linear Regression Analysis ◽  
Independent Variables ◽  
Hourly Data ◽  
Photochemical Oxidants

Solar radiation produces harmful compounds such as atmospheric oxidants and pharmaceutical intermediates through photochemical reactions. To clarify the variables related to the formation of photochemical oxidants, hourly data of air pollutants and climatic conditions in the Tokyo region of Japan from late May to early June 2020 were analyzed. Air pollutants, NO, NO2, CO, SO2, NMHCs and CH4, were significantly lower in 2020 than those in 2019. It seems to indicate that Japan's economic activity was suppressed by the COVID-19 emergency. Photochemical oxidants and NO were significantly higher during the day than at night. It shows the photochemical reaction is progressing during the day. Stepwise linear regression analysis revealed that relative humidity, ambient temperature, NO, CO, wind speed and NMHCs (non-methane hydrocarbons) were significant independent variables for photochemical oxidants formation.

scholarly journals Development and intercity transferability of land-use regression models for predicting ambient PM<sub>10</sub>, PM<sub>2.5</sub>, NO<sub>2</sub> and O<sub>3</sub> concentrations in northern Taiwan

2021 ◽  
Vol 21 (6) ◽  
pp. 5063-5078
Author(s):  
Zhiyuan Li ◽  
Kin-Fai Ho ◽  
Hsiao-Chi Chuang ◽  
Steve Hung Lam Yim
Keyword(s):  
Land Use ◽  
Air Pollution ◽  
Air Pollutants ◽  
Measurement Data ◽  
Air Pollutant ◽  
Population Exposure ◽  
Land Use Regression ◽  
Suspended Particulates ◽  
Model Based ◽  
Northern Taiwan

Abstract. To provide long-term air pollutant exposure estimates for epidemiological studies, it is essential to test the feasibility of developing land-use regression (LUR) models using only routine air quality measurement data and to evaluate the transferability of LUR models between nearby cities. In this study, we developed and evaluated the intercity transferability of annual-average LUR models for ambient respirable suspended particulates (PM10), fine suspended particulates (PM2.5), nitrogen dioxide (NO2) and ozone (O3) in the Taipei–Keelung metropolitan area of northern Taiwan in 2019. Ambient PM10, PM2.5, NO2 and O3 measurements at 30 fixed-site stations were used as the dependent variables, and a total of 156 potential predictor variables in six categories (i.e., population density, road network, land-use type, normalized difference vegetation index, meteorology and elevation) were extracted using buffer spatial analysis. The LUR models were developed using the supervised forward linear regression approach. The LUR models for ambient PM10, PM2.5, NO2 and O3 achieved relatively high prediction performance, with R2 values of > 0.72 and leave-one-out cross-validation (LOOCV) R2 values of > 0.53. The intercity transferability of LUR models varied among the air pollutants, with transfer-predictive R2 values of > 0.62 for NO2 and < 0.56 for the other three pollutants. The LUR-model-based 500 m × 500 m spatial-distribution maps of these air pollutants illustrated pollution hot spots and the heterogeneity of population exposure, which provide valuable information for policymakers in designing effective air pollution control strategies. The LUR-model-based air pollution exposure estimates captured the spatial variability in exposure for participants in a cohort study. This study highlights that LUR models can be reasonably established upon a routine monitoring network, but there exist uncertainties when transferring LUR models between nearby cities. To the best of our knowledge, this study is the first to evaluate the intercity transferability of LUR models in Asia.

Some Effects of Oxidant Air Pollutants (Ozone and Peroxyacetyl Nitrate) on the Ultrastructure of Leaf Tissues

1972 ◽  
Vol 30 ◽  
pp. 360-361
Author(s):  
William W. Thomson ◽  
Elizabeth S. Swanson
Keyword(s):  
Air Pollutants ◽  
Electron Microscopic Examination ◽  
Peroxyacetyl Nitrate ◽  
Electron Microscopic ◽  
Growth Physiology ◽  
Physiology And Biochemistry ◽  
Entire Plant ◽  
Leaf Tissues ◽  
Gaseous Hydrocarbons ◽  
The Individual

The oxidant air pollutants, ozone and peroxyacetyl nitrate, are produced in the atmosphere through the interaction of light with nitrogen oxides and gaseous hydrocarbons. These oxidants are phytotoxicants and are known to deleteriously affect plant growth, physiology, and biochemistry. In many instances they induce changes which lead to the death of cells, tissues, organs, and frequently the entire plant. The most obvious damage and biochemical changes are generally observed with leaves.Electron microscopic examination of leaves from bean (Phaseolus vulgaris L.) tobacco (Nicotiana tabacum L.) and cotton (Gossipyum hirsutum L.) fumigated for .5 to 2 hours with 0.3 -1 ppm of the individual oxidants revealed that changes in the ultrastructure of the cells occurred in a sequential fashion with time following the fumigation period. Although occasional cells showed severe damage immediately after fumigation, the most obvious change was an enhanced clarity of the cell membranes.

Freeze-dried dispersions for automated SEM analysis of individual submicron airborne particulates

1992 ◽  
Vol 50 (1) ◽  
pp. 408-409
Author(s):  
Karen A. Katrinak ◽  
David W. Brekke ◽  
John P. Hurley
Keyword(s):  
Air Pollutants ◽  
Size Range ◽  
Sem Analysis ◽  
Individual Particle ◽  
Chemical Data ◽  
Particle Analysis ◽  
Bulk Analysis ◽  
Airborne Particulates ◽  
Freeze Dried ◽  
Individual Particle Analysis

Individual-particle analysis is well established as an alternative to bulk analysis of airborne particulates. It yields size and chemical data on a particle-by-particle basis, information that is critical in predicting the behavior of air pollutants. Individual-particle analysis is especially important for particles with diameter < 1 μm, because particles in this size range have a disproportionately large effect on atmospheric visibility and health.

1735-P: Oral Exposure to Air Pollutants Mediates Diabetes via Innate Immunity

Diabetes ◽  
2019 ◽  
Vol 68 (Supplement 1) ◽  
pp. 1735-P
Author(s):  
ANGELA J.T. BOSCH ◽  
THERESA V. ROHM ◽  
SHEFAA ALASFOOR ◽  
ZORA BAUMANN ◽  
CLAUDIA CAVELTI-WEDER
Keyword(s):  
Innate Immunity ◽  
Air Pollutants ◽  
Oral Exposure
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