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Alkynes and are
Alkynes are traditionally known as acetylenes
, although
the name acetylene also refers specifically to
C < sub > 2
</ sub > H < sub > 2
</ sub >, known formally as ethyne using IUPAC nomenclature.
Alkynes are characteristically more unsaturated than alkenes.
Alkynes are usually more reactive than alkenes.
Alkynes characteristically undergo reactions
that show
that they
are " doubly unsaturated ," meaning
that each alkyne unit is capable of adding
two equivalents of
H < sub > 2
</ sub >, halogens or related HX reagents ( X = halide
, pseudohalide
, etc .).
Alkynes and <
< td
> Alkynes </ td
>
are and hydrocarbons

Greasy soils
, which
are typified by
hydrocarbons and fats ( esters of glycerol
with long-chain organic acids ).

Alkanes ( also known as paraffins or saturated
hydrocarbons )
are chemical compounds
that consist only of hydrogen and
carbon atoms and
are bonded exclusively by single bonds ( i. e., they
are saturated compounds ) without any cycles ( or loops ; i. e., cyclic structure ).

Saturated
hydrocarbons can also combine any of
the linear
, cyclic ( e. g., polycyclic ) and branching structures
, and they
are still alkanes ( no general
formula ) as long as they
are acyclic ( i. e., having no loops ). They also
have single covalent bonds
between their carbons.

Most aliphatic compounds
are flammable
, allowing
the use of
hydrocarbons as fuel
, such as methane in Bunsen burners and as liquified natural gas ( LNG ), and acetylene in welding.

Like other
hydrocarbons, alkynes
are generally hydrophobic but tend to be more reactive.

Plastics
are made from fossil
hydrocarbons, and
carbon fiber
, made by pyrolysis of synthetic polyester fibers is used to reinforce plastics to form advanced
, lightweight composite materials.

Chemically
, carotenes
are polyunsaturated
hydrocarbons containing 40
carbon atoms per molecule
, variable numbers of hydrogen
atoms, and no other elements.

Since they
are hydrocarbons, and therefore contain no oxygen
, carotenes
are fat-soluble and insoluble in water ( in contrast
with other carotenoids
, the xanthophylls
, which contain oxygen and thus
are less chemically hydrophobic ).

Coal tars
are complex and variable mixtures of phenols
, polycyclic aromatic
hydrocarbons ( PAHs ), and heterocyclic compounds
, about 200 substances in all.

Oxygen is more electronegative than
carbon, thus
the hydrogens alpha to ethers
are more acidic than in simple
hydrocarbons.

Unsaturated
hydrocarbons such as alkenes and alkynes
are considered Lewis bases.

Hydrogen is
the most common fuel
, but
hydrocarbons such as natural gas and alcohols like methanol
are sometimes used.

SOFCs
are capable of internally reforming light
hydrocarbons such as methane ( natural gas ), propane and butane.

Aromatic
hydrocarbons ( arenes ), alkanes
, alkenes
, cycloalkanes and alkyne-based compounds
are different types of
hydrocarbons.

The classifications for
hydrocarbons defined by IUPAC nomenclature of organic chemistry
are as follows:

# Saturated
hydrocarbons ( alkanes )
are the simplest of
the hydrocarbon species and
are composed entirely of single bonds and
are saturated
with hydrogen.
are and have

If it were not for an old professor who made me read
the classics I would
have been stymied on what to do
, and now I understand why they
are classics ; ;

When I show up he will know you
are a good wife to
have told him about it ''.

And both in their objectives of non-discrimination and of social progress they
have had ranged against them
the Southerners who
are called Bourbons.

But in our case -- and neither my wife nor I
have extreme views on integration
, nor
are we given to emotional outbursts --
the situation has ruined one or
two valued friendships and come close to wrecking several more.

Or else
the North really believes
that all Southerners except
a few quaint old characters
have come around to realizing
the errors of their past
, and
are now at heart sharers of
the American Dream
, like everybody else.

and I
have heard many say
that they
are content to earn
a half or
a third as much as they could up North because they so much prefer
the quieter habits of their home town.

Of greater importance
, however
, is
the content of those programs
, which
have had and
are having enormous consequences for
the American people.

I
have just asked these questions in
the Pentagon
, in
the White House
, in offices of key scientists across
the country and aboard
the submarines
that prowl for months underwater
, with neat rows of green launch tubes which contain Polaris missiles and which
are affectionately known as `` Sherwood Forest ''.

The experts
are thus forced to hypothesize sequences of events
that have never occurred
, probably never will -- but possibly might.

Only one rule prevailed in my conversations
with these men: The more highly placed they
are --
that is
, the more they know --
the more concerned they
have become.

They
are huge areas which
have been swept by winds for so many centuries
that there is no soil left
, but only deep bare ridges fifty or sixty yards apart
with ravines
between them thirty or forty feet deep and
the only thing
that moves is
a scuttling layer of sand.

The one apparent connection
between the two is
a score of buildings which somehow or other
have survived and which naturally enough
are called `` historical monuments ''.

Willard Thorp
, in his new book
, American Writing In The Twentieth Century
, observes
, quite validly it seems: `` Certain subjects
are conspicuously absent or
have been only lightly touched.

But
, since they
have rejected both narrative and emotional continuity
, how
are they to unify
the impressive array of materials at their disposal??

They
are in general those fears
that once seemed to
have been amenable to prayer or ritual.

In fact
, although we
have dispelled
the fear
, we
have not necessarily assured ourselves
that there
are no dangers.

We
have staved off
a war and
, since our behavior has involved all these elements
, we can only keep adding to our ritual without daring to abandon any part of it
, since we
have not
the slightest notion which parts
are effective.

We
are forced
, in our behavior towards others
, to adopt empirically successful patterns in toto because we
have such
a minimal understanding of their essential elements.

I
have chosen to use
the word `` mimesis '' in its Christian rather than its classic implications and to discover in
the concrete forms of both art and myth powers of theological expression which
, as in
the Christian mind
, are the direct consequence of involvement in historical experience
, which
are not reserved
, as in
the Greek mind
, only to moments of theoretical reflection.

Our most elemental and unavoidable impressions
, he says
, are those of being involved in
a large arena of powers which
have a longer past than our own
, which
are interrelated in
a vast movement through
the present toward
the future.

They
are presumed to
have plunged to
a common grave in this fatal embrace.
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