Ring expansion and ring contraction reactions expand or contract rings, usually in organic chemistry. The term usually refers to reactions involve making...

of a ring structure. This category is not broken down any further. All entries presently include: A classic example of ring opening and contraction is the...

Examples include: ring opening metathesis, which can also be used to accomplish a specific type of polymerization. Ring expansion and contraction reactions are...

the movement of the subfloor and the tiles themselves due to thermal expansion and contraction, moisture variations, and structural shifts. These joints...

skeleton derived therefrom by one or more bond scissions or ring expansions or contractions." Ayers D (1972). Bioscientific Terminology. Tucson: University...

After a failed contraction plan, MLB bought the Expos, seeking to move the team to a new city. MLB owners chose Washington, D.C., in 2004 and established...

side chain at C-17 and an hydroxyl group at C-3 In addition to the ring scissions (cleavages), expansions and contractions (cleavage and reclosing to a larger...

blood, and the resulting pressure closes the valves to the atria. The ventricles now perform isovolumetric contraction, which is contraction while all...

parameter, and cosmological constant. If the expansion stopped, then contraction will inevitably follow, accelerating as time passes and finishing the...

an undersized hole, sometimes used in combination: force and thermal expansion or contraction. There are at least three different terms used to describe...

influenced by environmental and climatic changes, such as the expansion and contraction of forests and the fluctuations of temperature and precipitation. They...

rearrangement is a ring expansion reaction, converting a vinyl-substituted cyclopropane ring into a cyclopentene ring. Cyclopropyl groups adjacent...

In medicine, the pulse refers to the rhythmic pulsations (expansion and contraction) of an artery in response to the cardiac cycle (heartbeat). The pulse...

keep the team in St. Louis and save them from contraction took over the team from then on in. In 1992, the NHL added an expansion franchise in Ottawa, in...

diastole with contraction of the left atrium, and the mitral valve closes during systole with contraction of the left ventricle. The valve opens and closes because...

conditions. This dehiscence causes the cells to shrink and a contraction and straightening of the annulus ring, eventually rupturing the sporangial wall by ripping...

unified entity of space and time, relativity of simultaneity, kinematic and gravitational time dilation, and length contraction. In the field of physics...

cycles and depressions: an encyclopedia. New York: Garland Publishing. pp. 148–149. ISBN 0-8240-0944-4. "Business Cycle Expansions and Contractions". National...

a ring of smooth muscle in the eye's middle layer, the uvea (vascular layer). It controls accommodation for viewing objects at varying distances and regulates...

the expansion is powered exclusively by relaxing the bell, which releases the energy stored from the contraction. Meanwhile, the second vortex ring starts...

definitive and can be further reduced). The ship has two thick outer rings (to reduce required energy) that generate the warp field—a contraction of space...

measurement error), dark energy does not lead to contraction of the universe but rather may accelerate its expansion. An expression for the critical density is...

the periphery experience the Lorentz contraction, but the rods upon the diameter do not experience this contraction (along their lengths!). It therefore...

rotation and thus producing a mixture of stereochemistry. Arylnitrene ring-expansion and ring-contraction: Aryl nitrenes show ring expansion to 7-membered...

cyclopentene dimer leads to expansion of 5.21% and the conversion of adamantane even to expansion of 14.15%. The third effect is the ring-opening effect which...

down and to the left on the table. Symmetrically, lowering an index corresponds to moving diagonally up and to the right on the table. Contraction of an...

poles the temperature inside the bellows can be regulated. The expansion or contraction of the bellows is used as an actuator to control a certain movement...

formally a ring contraction when used on cyclic diketones. It has been found that aryl groups more readily migrate than alkyl groups, and that aryl groups...

missing, and three small, unipennate, central muscles in the hand that lie between the metacarpal bones and are attached to the index, ring, and little...

a contraction of space ahead of the bubble and an expansion behind, but this interpretation could be misleading, since the contraction and expansion actually...