Sentences with phrase «of reactive nitrogen»

Export of reactive nitrogen from coal ‐ fired power plants in the U.S.: Estimates from a plume ‐ in ‐ grid modeling study

Dry deposition of reactive nitrogen to European ecosystems: a comparison of inferential models across the NitroEurope network.

However, if one considers the enormous increase of reactive nitrogen in our biosphere, due to the use of synthesized fertilizer and the burning of fossil fuels, its impact is not part of the analysis, even tough this increase shows up in the eutrophication (nutrient enrichment) of open waters all over the world, resulting in excess algae, in some areas causing large algae blooms (as where they are going to hold the sailing regattas during the Olympics), red tides and dead zone, as the 8000 square mile dead zone in the Gulf of Mexico.

One of the key processes involved in secondary damage is iNOS (Nitric oxide synthase)- mediated cell damage, through the generation of reactive nitrogen species peroxinitrates.

The Integrated Nitrogen Committee of the EPA's science advisory board, which held a June public teleconference on the issue of reactive nitrogen in the environment, has generated a draft report that lays out the details, including management options for nitric acid rain.

Actually, the scientists have already observed a redistribution of reactive nitrogen and signs of chlorine activation during measurement flights earlier this winter.

Not exact matches

Measurements from the winter of 1994 — 95 indicating removal of total reactive nitrogen from the Arctic stratosphere by particle sedimentation were used to constrain a microphysical model.

«Myeloid - derived suppressor cells (MDSCs) produce reactive nitrogen radicals that alter the receptors on the surface of the tumour to hide it from cytotoxic lymphocytes that kill tumour cells.

«Freshwater ecosystems, including lakes, streams and wetlands, are a large global sink for reactive nitrogen,» says lead author Jacques Finlay, an associate professor in the College of Biological Sciences (CBS).

The machine effectively detected ninhydrin - reactive nitrogen, one of the telling compounds of decomposition, in both sites as the animals disintegrated over the next 20 weeks.

In addition, particles of these clouds may descend and withdraw reactive nitrogen from the chlorine - activated layer — active chlorine is one of the substances mainly responsible for ozone destruction.

NOx gases represent some of the most reactive gases produced from diesel combustion and other fossil fuels, but the emissions limits for nitrogen dioxide are regularly exceeded, especially in urban areas.

«We show that uptake of atmospheric NH3 (ammonia) onto surfaces containing TiO2 (titanium dioxide) is not a permanent removal process, as previously thought, but rather a photochemical route for generating reactive oxides of nitrogen that play a role in air pollution and are associated with significant health effects,» the authors write.

They now think it consisted largely of carbon dioxide and nitrogen, a far less reactive mixture than Dr. Miller used.

Wang, M. Gao, Q. Zhang, K. He, G. Carmichael, U. Pöschl and H. Su: Reactive nitrogen chemistry in aerosol water as a source of sulfate during haze events in China, Science Advances 2 (12), e1601530, doi: 10.1126 / sciadv.1601530, 2016.

Manmade production of ammonia and nitrate fertilizers has exploded in recent decades and now vastly exceeds the amount of atmospheric nitrogen converted into reactive nitrogen by microbial organisms around the world.

Free radicals like reactive oxygen and nitrogen species (ROS, RNS) are molecules missing an electron, making them highly unstable and capable of destructive interactions with lipids, DNA, and proteins.

These powerhouse organelles are major sites of oxidative stress due to the high production of reactive oxygen species ROS (reactive oxygen species) and RNS (reactive nitrogen species).

Moreover, reactive nitrogen and oxygen species (RNOS) are used extensively in cellular signalling, and cells adaptively regulate endogenous antioxidants on short time scales to respond to deletorious spikes of RNOS faster than we could ever achieve with dietary antioxidants.

Similarly, a problem with antioxidant production can result in the buildup of reactive oxygen and nitrogen species, otherwise termed «free radicals», in the mitochondria.

Intracellular oxidative stress arises due to the imbalance in the production of reactive oxygen / reactive nitrogen species and cellular antioxidant defense mechanisms.

And although recognized that there also has been an enormous increase of nitrogenous oxides (reactive nitrogen) in the atmosphere (molecules that can adsorb much more energy than carbon dioxide) their much lower concentrations is hardly getting any attention, when global warming is discussed.

Since life mostly consist out of carbon, hydrogen, oxygen and «reactive nitrogen», ecosystems within the earth's biosphere were established based on what element was limiting.

These forcings are spatially heterogeneous and include the effect of aerosols on clouds and associated precipitation [e.g., Rosenfeld et al., 2008], the influence of aerosol deposition (e.g., black carbon (soot)[Flanner et al. 2007] and reactive nitrogen [Galloway et al., 2004]-RRB-, and the role of changes in land use / land cover [e.g., Takata et al., 2009].

Further, billions of pounds of additional reactive nitrogen are created inadvertently as a byproduct of fossil fuel combustion.

Many scientists now believe that several of these gases, including methane and nitrogen oxides, are among the reactive gases that can directly or indirectly deplete ozone, Dr. Setzer said.

In order of reduction, they call for controlling nitrogen oxide emissions from the burning of fossil fuels using «maximum feasible reductions,» which could reduce reactive nitrogen emissions by 55 billion pounds of a year; increasing the efficiency of fertilizing crops (33 billion pounds a year); improved animal management policies (33 billion pounds); and ensuring that at least half the world's urban population has sewage treatment (11 billion pounds).

While stating that «other intervention points are clearly needed» and that implementing just these four proposals «would not be trivial, they indicate that a multipronged, integrated approach can decrease the amount of (reactive nitrogen) lost to the environment.»

While the stable form of nitrogen in the air is no problem, «reactive nitrogen» — the chemically active form in things like ammonia and the air pollutant nitrogen oxide — can be.

A paragraph from a 2007 United Nations - sponsored report provides a depressing introduction: «In the air, (reactive nitrogen) can contribute to higher levels of ozone in the lower atmosphere, causing respiratory ailments and damaging vegetation.

Leaching out of the soils, reactive nitrogen can make groundwater and surface water unfit for human consumption.

The interactive effects of excess reactive nitrogen and climate change on aquatic ecosystems and water resources of the United States

More nitrogen is now converted into reactive forms by industry than all by all the planet's natural processes and our industrial and agricultural processes are causing a continual build - up of long - lived greenhouse gases to levels unprecedented in at least the last 800,000 years and possibly much longer.

Human emissions of reactive sulfur and nitrogen, derived from fossil fuel combustion and agriculture, have led to increased deposition of strong acids (HNO3 and H2SO4) and bases (NH3) to the ocean, hence affecting seawater pH (Doney et al. 2007).

The «Fuels of Freedom» are non-toxic, chemically inert but readily react with oxygen, halogens and several other highly reactive chemicals such as ozone, noncorrosive, highly portable, and can be stored indefinitely in sealed containers (e.g., steel drums) and under an inert atmosphere (e.g., nitrogen) in large tanks.

For example, early global chemical modelling results argued that global tropospheric ozone, a greenhouse gas, was controlled by emissions of the highly reactive gases nitrogen oxides (NOx), carbon monoxide (CO) and non-methane hydrocarbons (NMHC, also known as volatile organic compounds, VOC).

Emissions of carbon dioxide, methane, nitrous oxide and of reactive gases such as sulphur dioxide, nitrogen oxides, carbon monoxide and hydrocarbons, which lead to the formation of secondary pollutants including aerosol particles and tropospheric ozone, have increased substantially in response to human activities.