Sentences with phrase «of oxygen reduction»

«The efficiency is better than platinum in terms of oxygen reduction, permitting one to sidestep the most prohibitive hurdle in fuel - cell generation — the cost of the precious metal,» he said.

Not exact matches

Research on closures» impact on wine composition has clearly shown that the selection of closures with the appropriate oxygen transfer rate (OTR) can effectively assist winemakers in their efforts to address reduction and / or oxidation issues.

Another wine fault is the oxidation or reduction of the wine — which happens when wines are either exposed to too much oxygen or too little respectively.

Carys Mitchelmore of the University of Maryland's Chesapeake Biological Laboratory says a 30 per cent reduction in oxygen would be «highly significant» to some species.

NOAA also says the reduction in oxygen is not marked enough to be of concern.

Of the many ways to make oxygen from lunar soil, Clark has chosen hydrogen reduction.

The finding that cerium oxide may grab hydrogen as well as oxygen is promising for efforts to engineer it to catalyze both reactions that cause electron gain («reduction» of a reactant) and electron loss («oxidation»).

But climate models predict reductions in dissolved oxygen in all oceans as average global air and sea temperatures rise, and this may be the main driver of what is happening there, she says.

So the bacteria evidently form a sort of conductive chain, comprising biological nanowires and possibly pyrite grains embedded in the mud, that allows electrons from the oxidation of hydrogen sulfide and carbon within the sediment to contribute to the reduction of oxygen by other microbes at the sediment surface.

Illustration of the catalytic oxygen reduction reaction on the surface of platinum - nickel nanoframes with multilayered platinum skin structure.

The Pt3Ni nanoframe catalysts achieved a more than 36-fold and 22-fold enhancement in two different measures of catalytic activity (mass and specific activities, respectively) for the oxygen reduction reaction in comparison to state - of - the - art carbon - supported Pt catalysts (Pt / C) during prolonged exposure to reaction conditions.

Both the interior and exterior surfaces of this open framework structure are composed of a Pt - rich skin structure that exhibits enhanced oxygen reduction reaction activity.

«A control method that uses the reduction of dissolved oxygen to control zebra mussel activities was granted a U.S. Patent (# 5,376,282) in December 1994.

Catalysts that drive the oxygen reduction reaction that lets fuel cells turn chemical energy into electricity are usually made of platinum, which stands up to the acidic nature of the cell's charge - carrying electrolyte.

«We found a catalyst that is very good at driving both the opposing oxygen evolution reaction and the oxygen reduction reaction,» said senior author Ho Nyung Lee of ORNL's Materials Science and Technology Division.

The performance of the new catalyst was better than that of platinum, a noble metal that is known to excel at driving both oxygen evolution and reduction reactions.

«Based on this, we believe the first rise in oxygen may have been due to a substantial reduction in the efficiency of the oxygen sink,» Lee said.

«Because of this new structure they're taking on, they're naturally shortening the distances between platinum atoms, which makes the platinum more active for the oxygen reduction reaction,» says Luke Roling, a graduate student in Mavrikakis» lab.

«We also showed that TCL1 inhibits a mitochondrial enzyme required for in oxidative phosphorylation, leading to a reduction in oxygen consumption of the cells,» co-first author Shiho Aizawa explains.

Documented chemical behavior of these metals, which correlates with previously observed disturbances in oceanic carbon, oxygen and sulphur signatures, strongly suggests that these metal increases resulted from reductions of ocean oxygenation.

A reduction in the amount of oxygen dissolved in the oceans due to climate change is already discernible in some parts of the world and should be evident across large regions of the oceans between 2030 and 2040, according to a new study led by the National Center for Atmospheric Research (NCAR).

The material showed an oxygen reduction reaction of about 15 millivolts more in positive onset potential — the start of the reaction — and 70 percent larger current density than platinum - based catalysts.

This newly established lab is capable to design and fabricate a wide variety of advanced materials for oxygen reduction, hydrogen oxidation, water oxidation, and hydrogen evolution, among others.

A recent study by Drs. Thaler, O'Malley, Weinstein and other colleagues at Penn found that the TORS approach achieved a significant reduction in the apnea - hypopnea index (AHI)(an index used to assess the severity of sleep apnea), a significant improvement in minimum arterial oxygen saturation (the amount of oxygen in your blood that maintains healthy organ functioning), and a significant improvement in daytime drowsiness in patients.

Some of the river characteristics the Drone River sensors could continuously monitor for are pH, dissolved oxygen, oxidation - reduction potential, conductivity (salinity), turbidity, temperature and dissolved ions.

For this work, he has used a number of ultra-high vacuum surface science techniques to, for example, identify and explain several very unusual mechanistic features of the heterogeneous chemistry occurring in a catalytic converter including: a) the dramatically different CO oxidation reaction mechanism on ruthenium metal relative to other late transition metals; b) the structure sensitive selectivity of the NO reduction reaction on rhodium metal; c) deactivation of rhodium metal at high oxygen partial pressures; and d) the significantly different CO oxidation reaction mechanism over oxidized rhodium metal.

Specifically, researchers observed a reduction of reactive oxygen species; increase in collagen, which strengthens the fibrous cap; and reduction of the plaque necrotic core, and these changes were not observed in comparison with the free peptide or empty nanoparticles.

Increased application of rTMS corresponded with a reduction in intensity of visual phosphene hallucinations and was reflected in altered blood oxygen level - dependent signal; fMRI revealed focal excitatory discharges at the border of the lesion, highlighting the origin of phosphenes.

This is true, Zelenay noted, especially in the fuel cell cathode, where a relatively slow oxygen reduction reaction, or ORR, takes place that requires significant «loading» of platinum.

«In this paper we're tying the modeling and the microscopy results with the electrochemically determined high activity of a PGM - free oxygen reduction reaction catalyst,» Zelenay said.

He will study catalytic processes of oxygen evolution and CO2 reduction using ab initio calculations.

A reduction of regional stress such as nutrient runoff or the loss of oxygen can mitigate the impact of global stressors like ocean acidification and warming.

Inflammation is also reduced during this process through the reduction of reactive oxygen species (ROS) by up to 73 percent.

One eight - month IER trial in obesity - prone rats reported an increase in theproduction of reactive oxygen species (ROS), with no clear mechanistic explanations.26 Another trial, this time over six months, showed that IER - fed rats displayed marked reductions in diastolic compliance and cardiac reserve due to observed reductions in cardiomyocyte size and increased myocardial fibrosis.23 No human trials to date have reported any adverse effects on cardiovascular health during long - term IER.

HIE is the reduction of oxygen supply to tissues and the brain due to inadequate blood flow and has symptoms like decelerated fetal heart rate, low Apgar Scores, meconium aspiration pneumonia and stillbirths.

With the brain's disproportionate consumption of fuel (at just 2 percent of body weight, it uses around 20 percent of the body's glucose and oxygen), any regional reduction in fuel metabolism will have dramatic effects.25

An under - producing heart means a reduction in the transport of oxygen and nutrients to the organs of the body, and a reduction in the transport of wastes, toxins and carbon dioxide out of the body».

Furthermore, substituting oxygen for sulfur — causing oxidation — in sulfur - containing amino acids (including in the more rare S - adenosylmethionine) can have effects in methionine residues where the surface is exposed, causing an oxidation - reduction cycle, imparing the activity of «methionine sulfoxide reductase and the subsequent accumulation of methionine sulfoxide residues [that] are associated with age - related diseases, neurodegeneration, and shorter lifespan.»

Taking a deep breath can help get you out of that brief stress, improve oxygen circulation in your brain and body tissues and cause a reduction in.

Calorie restriction has also been associated with a reduction in oxidative stress, perhaps due to a change in the amount of reactive oxygen species produced in the mitochondria during normal cellular respiration [4] under calorie restricted conditions.

A University of Exeter (U-E) led study shows for the first time how nitrate in beetroot juice leads to a reduction in oxygen uptake, therefore making exercise less tiring Beetroot juice also aids in reducing your blood pressure.

At the university of Chicago School of Medicine it was learned that cooling of the body results in a decline in the production of our blood cells in the marrow of the bones which means less oxygen is delivered to the cells creating a further reduction in energy.

The physiologic effects of Hyperbaric Oxygen Therapy («HBOT») include improved oxygenation, intravascular and tissue gas bubble reduction, vasoconstriction, increased antimicrobial activity, modulation of inflammation, improved immune function, and angiogenesis.

The therapeutic dotential of dietary precursor modulation by a fish - oil - supplemented diet (n - 3 fatty acids), such as eicosapentaenoic acid (C20: 5,n - 3) and docosahexaenoic acid (C22: 6,n - 3) in the therapy of ulcerative colitis has been shown to result in a 35 % to 50 % decrease in neutrophil production of LTB4.28 Significant improvement in symptoms and histologic appearance of the rectal mucosa has been observed in several small series of patients with Crohn's disease and ulcerative colitis given fish oil at 3 to 4 g daily for 2 to 6 months in uncontrolled studies.29 However, a larger, randomized, double - blind trial comprising 96 patients with ulcerative colitis failed to reveal any benefit in remission maintenance or treatment of relapse on 4.5 g of eicosapentaenoic acid daily, despite a significant reduction in LTB4 synthesis by blood peripheral polymorphonuclear cells.30 It should be emphasized, however, that the anti-inflammatory actions of the fish oils, in addition to inhibition of LTB4, include suppression of IL - 1 and platelet activating factor synthesis and scavenging of free oxygen radicals.30 The impact of increased lipid peroxidation after fish oil supplementation should be considered when altering the n - 6: n - 3 fatty acid ratio.31 Antioxidant supplementation may be able to counteract the potentially adverse effects of n - 3 fatty acids.

Some of the proven mechanisms of action include release of endogenous opioids; stimulation of angiogenesis; reduction of the formation of fibrosis; reduction of inflammation; blockage of the effects of reactive oxygen species (ROS) release; neuronal regeneration and functional recovery; enhancement of wound closure; improvement of wound epithelialization, cellular content, granulation tissue formation, and collagen deposition; and bactericidal effects.

One of them seems to be a reduction in dissolved oxygen.

What does it take in terms of climate change / CO2 concentration to trigger a large reduction in the ocean's oxygen production?

But the evidence shows this can't be true; temperature changes before CO2 in every record of any duration for any time period; CO2 variability does not correlate with temperature at any point in the last 600 million years; atmospheric CO2 levels are currently at the lowest level in that period; in the 20th century most warming occurred before 1940 when human production of CO2 was very small; human production of CO2 increased the most after 1940 but global temperatures declined to 1985; from 2000 global temperatures declined while CO2 levels increased; and any reduction in CO2 threatens plant life, oxygen production, and therefore all life on the planet.

The Scottish study, published in the journal Nature Geoscience, also found that the changes in circulation resulted in a reduction of the amount of oxygen in the deep ocean.

Much of the organic matter associated with this high productivity sinks onto the relatively wide continental shelf, where decay results in the reduction of dissolved oxygen in bottom waters [5].