The central carbon of allene forms two sigma bonds and two pi bonds.

Forests are central to all human life because they provide a diverse range of resources: they store carbon, aid in regulating the planetary climate, purify water and mitigate natural hazards such as floods.

The other triose, the aldose H ( C = O )( CHOH )< sub > 2 </ sub > H ( glyceraldehyde ), has one chiral carbon — the central one, number 2 — which is bonded to groups-H ,-OH ,-C ( OH ) H < sub > 2 </ sub >, and -( C = O ) H. Therefore, it exists as two stereoisomers whose molecules are mirror images of each other ( like a left and a right glove ).

2-Oxoglutarate has turned out to be the central signalling molecule reflecting the carbon / nitrogen balance of cyanobacteria.

In the second phase, it radiates away its energy and fusion reactions cease, as the central star is not heavy enough to generate the core temperatures required for carbon and oxygen to fuse.

Common sources of carbon monoxide are tobacco smoke, space heaters using fossil fuels, defective central heating furnaces and automobile exhaust.

A few ( roughly 10 %) of the central stars of planetary nebulae are, despite their much lower ( typically ~ 0. 6 solar ) masses, also observationally of the WR-type ; i. e., they show emission line spectra with broad lines from helium, carbon and oxygen.

S < sub > N </ sub > 2 occurs where the central carbon atom is easily accessible to the nucleophile.

S < sub > N </ sub > 1 reactions tend to be important when the central carbon atom of the substrate is surrounded by bulky groups, both because such groups interfere sterically with the S < sub > N </ sub > 2 reaction ( discussed above ) and because a highly substituted carbon forms a stable carbocation.

The S < sub > N </ sub > 1 mechanism tends to dominate when the central carbon atom is surrounded by bulky groups because such groups sterically hinder the S < sub > N </ sub > 2 reaction.

Additionally, bulky substituents on the central carbon increase the rate of carbocation formation because of the relief of steric strain that occurs.

In carbon dioxide each oxygen shares four electrons with the central carbon, and these four electrons are counted in both the carbon octet and the oxygen octet.

The latter differing mainly by the hydroxyl group moving one carbon and the addition of two methyl groups that make the molecule lipophilic ( fat soluble ), ergo capable of crossing the lipid membrane sheaths of the central nervous system.

Hyperoxia can also indirectly cause carbon dioxide narcosis in patients with lung ailments such as chronic obstructive pulmonary disease or with central respiratory depression.

It has been established using X-ray crystallography that the molecule is effectively coplanar with slight nitrogen pyramidalization, and that the central carbon bonds are longer ( 144 pm ) than what would be expected for a double bond ( 136 pm ).

Other bacteria simply use sialic acid as a good nutrient source, as it contains both carbon and nitrogen and can be converted to fructose-6-phosphate, which can then enter central metabolism.

If the star's mass, when on the main sequence, was below approximately 0. 5 solar masses, it is thought that it will never attain the central temperatures necessary to fuse helium .< sup >, p. 169 .</ sup > It will therefore remain a hydrogen-fusing red giant until it eventually becomes a helium white dwarf .< sup >, § 4. 1, 6. 1 .</ sup > Otherwise, when the core temperature reaches approximately 10 < sup > 8 </ sup > K, helium will begin to fuse to carbon and oxygen in the core by the triple-alpha process .< sup >,§ 5. 9, chapter 6 .</ sup > The energy generated by helium fusion causes the core to expand.

Note the negatively-charged transition state in brackets in which the central carbon atom in question shows five bonds, an unstable condition.

It has been reported that in 1811 French physicist Augustin Jean Fresnel discovered that sodium bicarbonate precipitates when carbon dioxide is bubbled through ammonia-containing brine — which is the chemical reaction central to the Solvay process.

The Superleggera is lighter than the base Gallardo by via the use of carbon fibre panels for the rear diffuser, undertray, the rearview-mirror housings, the interior door panels, the central tunnel, engine cover ; titanium wheel nuts and carbon fibre sports seats.

Why, in the first place, call himself a liberal if he is against laissez-faire and favors an authoritarian central government with womb-to-tomb controls over everybody??

The central concern of Erich Auerbach's impressive volume called Mimesis is to describe the shift from a classic theory of imitation ( based upon a recognition of levels of truth ) to a Christian theory of imitation in which the levels are dissolved.

Almost nothing is said of Charles' spectacular victories, the central theme being the heroic loyalty of the Swedish people to their idolized king in misfortune and defeat.

An advantage of being exposed to such specificity about an important and recurring feature of social reality is that it can be taken advantage of by the reader to examine covert as well as overt resonances within himself, resonances triggered by explicit symbols clustering around the central figure of the Jew.

It is obvious that the historian who seeks to recapture the ideas that have motivated human behavior throughout a given period will find the art and literature of that age one of his central and major concerns, by no means a mere supplement or adjunct of significant historical research.

The Walnut Trees Of Altenburg is composed in the form of a triptych, with the two small side panels framing and enclosing the main central episode of the novel.

There is a trend to packaging meat at a central source, freezing it, and shipping it to outlying stores, where meat cutters will not be required.

The girls are kept booked and moving by several agents, notably voluble, black-bearded Murat Somay, a Manhattan Turk who is the Sol Hurok of the central abdomen.

One matter of concern to the complete effectiveness of pool operations is the lack of adequate central garage facilities.

You can install it yourself -- this is a central system that will cool every part of your house.

Best of all, central air conditioning is something you can afford.

No matter what style your home is, ranch, two-story, Colonial or contemporary, central air conditioning is easily installed.

Its oil for heating is metered monthly to each home from a line that starts at a central storage point.

The idea of a central tank with lines to each house is not in itself a novelty.

On this first venture the central storage is 20,000 gallons, in two tanks, or an average of 400 gallons for each of the 50 homes.

The central storage is near a main artery quite easy to reach with large transports on a short crescent swing, with fewer trucks in the residential streets.

The measured brightness temperature is a good approximation to the brightness temperature at the center of the lunar disk because of the narrow antenna beam and because the temperature distribution over the central portion of the moon's disk is nearly uniform.

Furthermore, conditioned reactions are fundamentally altered when the hypothalamic sympathetic reactivity is augmented beyond a critical level, and several types of behavioral changes probably related to the degree of central autonomic `` tuning '' are observed.

It has further been shown that: ( 1 ) an experimental neurosis in its initial stages is associated with a reversible shift in the central autonomic balance ; ;

And in the economy of the book it is not peripheral but central.

This movement of industry away from the central cities is not so catastrophically new as some prophets seem to believe.

Only a radical change in the nature of the population in the central city would be likely to destroy this preference -- and we must now turn our attention to the question of whether such a change, gloomily foreseen by so many urban diagnosticians, is actually upon us.

Both of them did communicate one central theme: Against the ruin of the world, there is only one defense -- the creative act.