نتایج جستجو برای: and o3

تعداد نتایج: 16828599  

2005

A critical global climate change issue is how increasing concentrations of atmospheric CO2 and ground-level O3 will affect agricultural productivity. This includes effects on decomposition of residues left in the field and availability of mineral nutrients to subsequent crops. To address questions about decomposition processes, a 2-year experiment was conducted to determine the chemistry and de...

Journal: :Journal of applied physiology 1998
T Takebayashi J Abraham G G Murthy C Lilly I Rodger S A Shore

Previous studies that used neonatal capsaicin (Cap) treatment to ablate C fibers indicate that C fibers act to inhibit lung damage and airway hyperresponsiveness after ozone (O3) exposure in rats. The purpose of this study was to determine 1) the role of tachykinins in these protective effects and 2) whether differences in minute ventilation (VE) during O3 exposure might account for the effect ...

Journal: :international journal of nano dimension 0
aref shokri young researchers and elite club, arak branch, islamic azad university, arak, iran.

abstract: in this project, a nano catalyst (tio2) and ozone combined with each other and they were used for the removal of 4-nitrophenol (4np) in industerial wastewater. the effect of some operational parameters such as initial ph (3-9), the concentration of pollutant (20-80 mg/l), and amount of tio2 were investigated. in o3/tio2 process, the anion radical  formed before the production of hydro...

2013
H E Rieder

In order to quantify the impact of recent efforts to abate surface ozone (O3) pollution, we analyze changes in the frequency and return level of summertime (JJA) high surface O3 events over the eastern United States (US) from 1988–1998 to 1999–2009. We apply methods from extreme value theory (EVT) to maximum daily 8-hour average ozone (MDA8 O3) observed by the Clean Air Status and Trends Networ...

2016
Jürg Fuhrer Maria Val Martin Gina Mills Colette L. Heald Harry Harmens Felicity Hayes Katrina Sharps Jürgen Bender Mike R. Ashmore

Risks associated with exposure of individual plant species to ozone (O3) are well documented, but implications for terrestrial biodiversity and ecosystem processes have received insufficient attention. This is an important gap because feedbacks to the atmosphere may change as future O3 levels increase or decrease, depending on air quality and climate policies. Global simulation of O3 using the ...

2014
G. Michalski S. K. Bhattacharya

The oxygen isotope composition of nitrogen oxides (NOx) in the atmosphere is a useful tool for understanding the oxidation of NOx into nitric acid / nitrate in the atmosphere. A set of experiments was conducted to examine change in isotopic composition of NOx due to NOx–O2– O3 photochemical cycling. At low NOx / O2 mixing ratios, NOx became progressively and nearly equally enriched in 17O and 1...

Journal: :Journal of applied physiology 1999
M Longphre L Zhang J R Harkema S R Kleeberger

Ozone (O3) exposure stimulates airway inflammation and epithelial sloughing in a number of species, including mice. Platelet-activating factor (PAF) is a lipid mediator released by activated mast cells, macrophages, and epithelial cells and causes pulmonary inflammation and hyperpermeability. We hypothesized that the activation of PAF receptors is central to the development of inflammation and ...

2017
Ruth M. Doherty Mathew R. Heal Fiona M. O’Connor

This review examines the current literature on the effects of future emissions and climate change on particulate matter (PM) and O3 air quality and on the consequent health impacts, with a focus on Europe. There is considerable literature on the effects of climate change on O3 but fewer studies on the effects of climate change on PM concentrations. Under the latest Intergovernmental Panel on Cl...

2004
Pedro Jiménez José M. Baldasano

[1] The kinetics of ozone (O3) chemistry and its two main precursors, nitrogen oxides (NOx) and volatile organic compounds (VOC), represents an important field of uncertainty in atmospheric chemistry and photochemical modeling. This uncertainty affects the design of control strategies to reduce tropospheric O3 production. The effect of controlling ozone precursors on sensitivity regimes was eva...

2000
Youbin Zheng Tom Lyons Jeremy Barnes

The impact of ozone (O3) on the production and utilization of photoassimilates was examined in Plantago major population ‘Valsain’. Plants were exposed in controlled environment chambers to either charcoal/Purafil-filtered air (CFA) or CFA plus O3 (15 nmol mol −1 O3 overnight rising to a maximum of 75 nmol mol −1 between 12:00 and 16:00 h). Measurements of leaf gas exchange and non-structural c...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید