It is important to realize that the word problem is in fact solvable for many groups G. For example, polycyclic groups have solvable word problems since the normal form of an arbitrary word in a polycyclic presentation is readily computable ; other algorithms for groups may, in suitable circumstances, also solve the word problem, see the Todd – Coxeter algorithm and the Knuth – Bendix completion algorithm.

In some gasifiers this process is preceded by pyrolysis, where the biomass or coal is first converted to char, releasing methane and tar rich in polycyclic aromatic hydrocarbons.

Of major concern is the fact that the polycyclic aromatic hydrocarbons found in tobacco smoke are potent inducers of CYP1A2 so that smokers may require significant modification of medication dosage.

Anthracene is a solid polycyclic aromatic hydrocarbon consisting of three fused benzene rings.

Like many other polycyclic aromatic hydrocarbons ( PAH ), anthracene is carcinogenic as listed by OSHA.

According to a study by Slabunov ( 1999 ): " The Belomorian Province is a mobile belt that evolved in a polycyclic manner.

When this requirement is not enforced, for example in the adamantanone or other polycyclic ketones, the enolization is impossible or very slow.

Phenanthrene is a polycyclic aromatic hydrocarbon composed of three fused benzene rings.

Coronene ( also known as superbenzene ) is a polycyclic aromatic hydrocarbon ( PAH ) comprising six peri-fused benzene rings.

This model is used for describing polycyclic hydrocarbons consisting of condensed systems of benzenoid rings in which no C atom belongs to more than two rings and every C atom is on the periphery.

It is dissimilar to soot in its much higher surface-area-to-volume ratio and significantly lower ( negligible and non-bioavailable ) PAH ( polycyclic aromatic hydrocarbon ) content.

Benzopyrene is a polycyclic aromatic hydrocarbon found in coal tar with the formula C < sub > 20 </ sub > H < sub > 12 </ sub >.

Methylcholanthrene ( MCA ) is a highly carcinogenic polycyclic aromatic hydrocarbon produced by burning organic compounds at very high temperatures.

* A study has shown that church air is harmful and likely to contain carcinogenic polycyclic hydrocarbons when compared to roads travelled by 45, 000 cars per day.

The border of a hive is described as polycyclic, or made up of many circles, and changes as fluid leaks out and then is absorbed.

Related to micelle formation is the technologically important ability of detergent actives to congregate at oil - water interfaces in such a manner that the polar ( or ionized ) end of the molecule is directed towards the aqueous phase and the hydrocarbon chain towards the oily phase.

There is no limit to the number of carbon atoms that can be linked together, the only limitation being that the molecule is acyclic, is saturated, and is a hydrocarbon.

An aromatic hydrocarbon or arene ( or sometimes aryl hydrocarbon ) is a hydrocarbon with alternating double and single bonds between carbon atoms forming rings.

The configuration of six carbon atoms in aromatic compounds is known as a benzene ring, after the simplest possible such hydrocarbon, benzene.

Benzene, C < sub > 6 </ sub > H < sub > 6 </ sub >, is the simplest aromatic hydrocarbon and was recognized as the first aromatic hydrocarbon, with the nature of its bonding first being recognized by Friedrich August Kekulé von Stradonitz in the 19th century.

Generally, the chemical equation for stoichiometric burning of hydrocarbon in oxygen is

Generally, the chemical equation for stoichiometric incomplete combustion of hydrocarbon in oxygen is as follows:

The simple word equation for the combustion of a hydrocarbon in oxygen is:

The simple word equation for this type of combustion is hydrocarbon in air:

For example, an " X " is used to indicate a variable group amongst a class of compounds ( though usually a halogen ), while " R " is used for a radical, meaning a compound structure such as a hydrocarbon chain.

Food is similar to hydrocarbon fuel and carbohydrate fuels, and when it is oxidized, its caloric content is similar ( though not assessed in the same way as a hydrocarbon fuel — see food energy ).

This type of reaction is found mainly in aliphatic hydrocarbons, and rarely in aromatic hydrocarbon.

For the family is the simplest example of just such a unit, composed of people, which gives us both some immunity from, and a way of dealing with, other people.

The music which Lautner has composed for this episode is for the most part `` rather pretty and perfectly banal ''.

As long as perception is seen as composed only of isolated sense data, most of the quality and interconnectedness of existence loses its objectivity, becomes an invention of consciousness, and the result is a philosophical scepticism.

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.

From this point of view the `` militant mobs '' of the past, stirred into action by one ideology or another, were all composed of `` intellectuals '' -- and this is not the level on which the essence of mankind can be discovered.

The system is composed of three credit services, Federal Land Banks and National Farm Loan Associations, Federal Intermediate ( short-term ) Credit Banks, and Banks for Cooperatives.

The `` C '' club is composed of the men of the College who have won an official letter in Carleton athletics.

Each male willow catkin is composed of a large number of small flowers.

If three dice are tossed, a trial is one toss of one die and the experiment is composed of three trials.

When this experiment is viewed as composed of five binomial trials, one for each member of the family, the outcomes of the trials are obviously not independent.

If the inner functions of religion are performed, the individual is a composed, ordered, motivated, and emotionally secure associate ; ;

The bondage endurable by an oral poet is to be estimated only by a very skilful oral poet, but it appears safe to assume that no sustained narrative in rhyme could be composed without extreme difficulty, even in a language of many terminal inflections.

Libyan Desert silica-glass, another natural glass, is composed of nearly pure silica and has the same trace germanium content as sands in the area.

The second agreement permits the authority to sell a 520-acre tract west of Stage 1 Residential to Philadelphia Builders Eastwick Corp., a firm composed of 10 Philadelphia area builders, which is interested in developing part of the project.

Although the fatty protein molecules, carried in the blood and partly composed of cholesterol, are water soluble, cholesterol itself is insoluble, and cannot be destroyed by the body.

It is during this period in Athens from 335 to 323 BC when Aristotle is believed to have composed many of his works.

The order of the books ( or the teachings from which they are composed ) is not certain, but this list was derived from analysis of Aristotle's writings.

UTC is a discontinuous time scale composed from segments that are linear transformations of atomic time, the discontinuities being arranged so that UTC approximated UT2 until the end of 1971, and UT1 thereafter.

A central massif composed of uplifted blocks and downfolded troughs, covered by recent deposits and giving the appearance of a plateau with rough terrain, is wedged between two folded mountain ranges that converge in the east.

The concept that matter is composed of discrete units and cannot be divided into arbitrarily tiny quantities has been around for millennia, but these ideas were founded in abstract, philosophical reasoning rather than experimentation and empirical observation.

Though the word atom originally denoted a particle that cannot be cut into smaller particles, in modern scientific usage the atom is composed of various subatomic particles.

Allieae is sister to a clade composed of Tulbaghia and Gilliesieae.