Propadiene, the simplest allene, is also known as allene.

An allene is a compound in which one carbon atom has double bonds with each of its two adjacent carbon centres.

The parent compound of allene is propadiene.

The bond angle formed by the three carbons is 180 °, indicating linear geometry for the carbons of allene.

* Using a suitable catalyst ( e. g. Wilkinson's catalyst ), it is possible to reduce just one of the double bonds of an allene.

Some dienes: A: 1, 2-Propadiene, also known as allene, is the simplest cumulated diene.

It is a component of MAPP gas along with its isomer propadiene ( allene ), which is commonly used in gas welding.

Carbomers differ from their templates in size but not in symmetry when each C – C single bond is replaced by at least one alkyne bond, and when a double bond is replaced by an allene bond.

The size of the carbomer will continue to increase when more alkyne bonds are introduced and for this reason carbomers are also called carbo < sup > n </ sup >- molecules, where " n " is the number of acetylene or allene groups in an n-expansion unit.

In a novel concept, so-called chiral ions team up with traditional cationic catalysts in asymmetric synthesis as demonstrated in this allene hydroxyalkoxylation in which the active catalyst is a salt of gold ( I ) and a phosphate of a chiral binaphthol:

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

Because of the symmetry, an unsubstituted allene has no net dipole moment.

An allene with two different substituents on each of the two carbons will be chiral because there will no longer be any mirror planes.

In carbo-benzene the ring bonds are extended with alkyne and allene groups.

Certain allene compounds also display axial chirality.

This allene rearranges to the triazafulvene in a 1, 3-dipolar cycloaddition.

Several syntheses of substituted dendralenes have been reported, one via an allene, one via a Horner – Wadsworth – Emmons reaction, one via a cross-coupling reaction and one from an allylic carbonate.

From left to right: propadiene ( allene ), butatriene ( cumulene ), buta-1, 2-diene, penta-2, 3-diene.

It is this subject matter that has brought Mason a large and enthusiastic following among sportsmen, but it is his exceptional performance with this motif that commends him to artists and discerning collectors.

Once he has been identified, however, a new melody is used to accompany his narrative, a bleak motif with barren octaves creating a rather ancient effect:

" This is the iconic motif by which Actaeon is recognized, both in ancient art and in Renaissance and post-Renaissance depictions.

It is an example of the widespread motif of Greek ( or Indo-European more generally ) names expressing " battle-prowess ", in this case the ability to withstand or push back an enemy battle line.

The subject has been popular in art since classical times ; it is one of several Greek myths of a Greek hero's rescue of the intended victim of an archaic sacred marriage, giving rise to the " princess and dragon " motif.

Prayer is a major motif in both the Gospel of Luke and Acts.

Inspired by the Black Death, The Dance of Death, an allegory on the universality of death, is a common painting motif in the late medieval period.

This trend is already apparent by the 8-coordination in CsCl, vs the halite motif adopted by the other alkali metal chlorides.

Also called the " caesium chloride structure ", this structural motif is composed of a primitive cubic lattice with a two-atom basis, each with an eightfold coordination ; the chloride atoms lie upon the lattice points at the edges of the cube, while the caesium atoms lie in the holes in the center of the cubes.

One of the potential helmet designs Brown rejected was a striped motif that was similar to the helmets adopted by the team in 1981 and which is still in use to this day ; however, that design featured yellow stripes on a turquoise helmet which were more uniform in width.

The echinus itself is decorated with an egg-and-dart motif.

According to David Leeming, writing in The Oxford Companion to World Mythology, the harrowing of hell is an example of the motif of the hero's descent to the underworld, which is common in many mythologies.

The contrasts between the tall, thin, fancy-struck, and idealistic Quixote and the fat, squat, world-weary Panza is a motif echoed ever since the book ’ s publication, and Don Quixote's imaginings are the butt of outrageous and cruel practical jokes in the novel.

The motif is continued in Greek Apollo, and the early Christian narratives about Archangel Michael and Saint George.

Dedham pottery is a cherished class of antiques, characterized by a distinctive crackle glaze, blue-and-white color scheme, and a frequent motif of rabbits and other animals.

In the tradition of Holy Writ, the impossibility of coming face to face with God is a recurring motif, thus the commandment against graven images ( Exodus 20. 4-5 ).

The other motif that appears is Epictetus ' opinion on the judgment of events:

The design of the first Stars and Stripes by Hopkinson had the thirteen stars arranged in a " staggered " pattern technically known as quincuncial because it is based on the repetition of a motif of five units.

The flag is a common motif on decals for car windows, and clothing ornaments such as badges and lapel pins.

This sculpture is typical of the themes and style of this artist, and the most significant example of his " inside / outside " motif.

In most GTPases, the specificity for the base guanine is imparted by the base-recognition motif, which has the consensus sequence KXD.

" Nobody is entirely sure why the number seven appears frequently in the games, however, many are convinced that this is indeed a recurring motif in many of Bungie's games.

In the early years of the show, cast members ( especially Christine ) were frequently nailed with pails of water physically thrown on them, but starting in 1981, this began to change to the much more mysterious motif of water falling down on the victim from above.

Decorative borders on pages in the book combine this design with the swastika, a motif that also appears frequently in other books by Ryan.

In film, such a motif is most frequently a plot device, image, character trait, or element of the mise en scène.

One of the most frequently occurring examples of a musical cryptogram, the motif has been used by countless composers, especially after the Bach Revival in the first half of the 19th century.

Birds are a motif that shows up frequently in Bécquer's canon, like in " Rima LIII " ( Rhyme 53 ), where swallows appear as a sign of the end to a passionate relationship.

The motif is named for Michael Rossmann, who first pointed out that this is a frequently occurring motif in nucleotide binding proteins, such as dehydrogenases.

In the form of the palmette that appears most frequently on Greek pottery, often interspersed with scenes of heroic deeds, the same motif is bound within a leaf-shaped or lotus-bud shaped outer line.

( 2004 ) inserted an RGD motif in the HI loop of the fiber knob protein, shifting specificity toward integrins, which are frequently over-expressed in Oesophageal Adenocarcinoma.

* In official supplemental materials for Neon Genesis Evangelion, the impact that created the Moon-known in-universe as First Impact-is revealed to have been caused by the " Black Moon ", an artificial construct carrying the Angel Lilith ; as an allusion, Rei Ayanami is frequently depicted in the series and in official artwork with a full moon motif.

The columnella would then be used as a pendant, a motif that shows up frequently in Southeastern Ceremonial Complex designs.

Dharmakirti held the mindstream to be beginningless yet also described the mindstream as a temporal sequence, and that as there are no true beginnings, there are no true endings, hence, the " beginningless time " motif that is frequently used to describe the concept of mindstream, as Dunne ( 2004: p. 1 ) relates:

Yurts are also frequently used as a decorative motif in restaurants and other public buildings.

The centre strips of the field emblems, a recurring symbol in Barney's works, are then pulled off, a frequently repeated motif throughout the film.

A third staff, which requires the pianist to perform large jumps with both hands frequently, contains the a motif from the earlier orchestral accompaniment.

She supports Allison's view that women / girls portrayed in their underwear ( or naked ) is a common motif in Japanese comics, and is most frequently accompanied by a masculine " viewer " whose voyeuristic presence is indicative of the male gaze.