Sentences with phrase «by deuterium»

Dietary cholesterol feeding suppresses human cholesterol synthesis measured by deuterium incorporation and urinary mevalonic acid levels.

PHWRs are similar to PWRs, but use raw uranium rather than enriched uranium oxide as fuel, and deploy heavy water — in which hydrogen is replaced by deuterium — as both moderator and coolant.

When surrounded by deuterium atoms (heavy hydrogen), that voltage gives the atoms an electric charge and then accelerates them into a nearby solid target containing additional deuterium.

Not exact matches

A fusion power plant, on the other hand, will generate energy by fusing atoms of deuterium and tritium, two isotopes of hydrogen — the lightest element.

However, the Rosina mass spectrometer aboard Rosetta found that the ratio of deuterium to hydrogen in the comet is far greater than that found on Earth, adding to the growing body of evidence that the water on Earth was delivered not by comets, as previously thought, but by asteroids.

Meanwhile, science can characterize the content of deuterium (a hydrogen nucleus with a proton and a neutron) to the usual quality limits by looking at a spectra from 1000 hydrogen atoms.

Deuterium enrichment profile of Golden Rice β - carotene analyzed by liquid chromatography / atmospheric pressure chemical ionization - mass spectrometry (positive ion mode).

Spinach or carrot can supply significant amounts of vitamin A as assessed by feeding with intrinsically deuterium - labeled vegetables

With this labeling method, the intrinsically labeled Golden Rice β - carotene showed a protonated molecule of m / z of Mβc + H + = 536 + 1 (representing unlabeled β - carotene) and a range of isotopomers with the most abundant showing an enrichment of 9 deuterium at Menrich - βc = Mβc + H + + 9 mass units (Figure 4) as analyzed by using the liquid chromatography / mass spectrometry with a positive atmospheric pressure chemical ionization interface (the total m / z was Mβc + 9 + H + = 536 + 9 + 1 = m / z 546)(23).

Urey and two colleagues then detected deuterium by its atomic spectrum in residue distilled from liquid hydrogen.

«By comparing our calculations with cosmological observables, such as the deuterium abundance,» says Grohs, «we can use our BURST computer code to test theories regarding neutrinos, along with other — even less understood — particles.

The team succeeded by using deuteration, or the substitution of deuterium atoms for hydrogen atoms, to study how hydroxyl is produced.

Aura found that the early moisture accumulating over the rainforest was high in deuterium — «too high to be explained by water vapor from the ocean,» Fu says.

Inertial confinement fusion (ICF) seeks to create those conditions by taking a tiny capsule of fusion fuel (typically a mixture of the hydrogen isotopes deuterium and tritium) and crushing it at high speed using some form of «driver,» such as lasers, particle beams, or magnetic pulses.

The International Thermonuclear Experimental Reactor (ITER) aims to produce 500 megawatts of power by burning a plasma of deuterium and tritium held in place by superconducting magnets in a doughnut - shaped vessel called a torus.

The original branch of the field focuses on infusing deuterium into a palladium electrode by turning on the power, Nagel explains.

The issue first raised its head in 2015, when a team led by Edmund Myers at Florida State University measured the difference in masses of the nucleus of a helium - 3 atom and a deuteron — the nucleus of a deuterium or heavy hydrogen atom — with a single proton bound to...

They were able to get further information about the amino acids involved by using a combination of deuterium oxide, or heavy water, and normal water as a solvent.

The school will be structured around lectures delivered by members of CNL's research team and external experts in the mornings, followed by demonstrations and practical sessions in the afternoons during which students will spend time at the Zero Energy Deuterium (ZED - 2) reactor, as well as several other nuclear facilities located on the campus.

Burke's research takes an innovative approach by combining several sophisticated biophysical and biochemical techniques, including hydrogen - deuterium exchange mass spectrometry, X-ray crystallography, surface plasmon resonance, isothermal titration calorimetry and functional assays.

But by altering the simulation's parameters to give it a lower starting level of neutrons and a higher level of already - freed protons, the team found the universe could still form heavy hydrogen, or deuterium, and with it the basis of life.

The Sun derives most of its heat by the fusion of deuterium into helium.8 The peak of the binding energy curve (above) is around 60 AMU (near iron), so fusion normally9 merges into nuclei lighter than 60 AMU.

If two deuterium nuclei merge to become helium, 2.2 MeV + 2.2 MeV of binding energy are replaced by helium - 4's average binding energy of 7.1 MeV per nucleon, or a total of 4 x 7.1 MeV.

Following the proton reactions was a tricky and challenging task, said Seefeldt, so to ensure accuracy they monitored the proton «inventory» (the number of hydrogens involved in the catalytic production of H2) by performing kinetic hydrogen / deuterium kinetic measurements.

A team of scientists from Pacific Northwest National Laboratory, Utah State University, Northwestern University, and the University of Utah sought to understand this H2 relaxation mechanism by monitoring the effects of hydrogen (H) vs deuterium (D) on the kinetics of H2 formation when nitrogenase is attached to an electrode.

Thus, Adams and Grohs deuterium would have far more time to be hit by protons and turn into helium.

A new study by an international team of researchers, affiliated with UNIST has announced that they have succeeded in developing a novel deuterium separation method, using a special class of metal organic frameworks (MOFs) whose pore dimensi... Read More

Some of this short - lived deuterium would then be hit by protons before it could split apart, forming helium.

In a previous paper (Franco et al. (2011) Proc Natl Acad Sci USA 108:9, 3797 - 802) we showed that fruit flies can recognize the presence of deuterium in odorants by a vibrational mechanism.

Drosophila appears able to recognize the presence of deuterium in odorant isotopomers by a vibrational mechanism [12].

The end of the first half of the Holocene — between about 5 and 4 ka — was punctuated by rapid events at various latitudes, such as an abrupt increase in NH sea ice cover (Jennings et al., 2001); a decrease in Greenland deuterium excess, reflecting a change in the hydrological cycle (Masson - Delmotte et al., 2005b); abrupt cooling events in European climate (Seppa and Birks, 2001; Lauritzen, 2003); widespread North American drought for centuries (Booth et al., 2005); and changes in South American climate (Marchant and Hooghiemstra, 2004).

The deuterium excess, a proxy of Greenland precipitation moisture source, switches mode within 1 - 3 years over these transitions and initiates a more gradual change (50 years) of the Greenland air temperature as recorded by water stable isotopes.

The amount of energy available through fusion is extraordinary.Fusion energy is obtained by forcing together atomic nuclei from deuterium and tritium (another form of hydrogen).

By measuring the ratio of «normal» hydrogen to the heavier deuterium, Dr Robert Mulvaney and his team were able to make a detailed reconstruction of temperatures spanning the last 15,000 years.

... The paper, entitled «Recent Antarctic Peninsula warming relative to Holocene climate and ice — shelf history» and authored by Robert Mulvaney and colleagues of the British Antarctic Survey (Nature, 2012, doi: 10.1038 / nature11391), reports two recent natural warming cycles, one around 1500 AD and another around 400 AD (William: Same periodicity of cyclic warming and cooling in the Northern hemisphere), measured from isotope (deuterium) concentrations in ice cores bored adjacent to recent breaks in the ice shelf in northeast Antarctica.

The problem with your analysis is that the ice cores already reflect the ocean temperature by measuring the ratio of Deuterium to Hydrogen based on the difference in the relative evaporation of each, vs. temperature.

That Venus had a primordial ocean, with most of the water subsequently lost to space, is confirmed by the present enrichment of deuterium over ordinary hydrogen by a factor of 100 [107], the heavier deuterium being less efficient in escaping gravity to space.

One involves working out what is called the deuterium excess by comparing the relative amounts of deuterium and oxygen - 18 in the ice.