Activator

Activator may refer to:

Enzyme activator

Enzyme activators are molecules that bind to enzymes and increase their activity. They are the opposite of enzyme inhibitors. These molecules are often involved in the allosteric regulation of enzymes in the control of metabolism. An example of an enzyme activator working in this way is fructose 2,6-bisphosphate, which activates phosphofructokinase 1 and increases the rate of glycolysis in response to the hormone insulin.

See also

References

Activator (phosphor)

In phosphors and scintillators, the activator is the element added as dopant to the crystal of the material to create desired type of nonhomogeneities.

In luminescence, only a small fraction of atoms, called emission centers or luminescence centers, emit light. In inorganic phosphors, these inhomogeneities in the crystal structure are created usually by addition of a trace amount of dopants, impurities called activators. (In rare cases dislocations or other crystal defects can play the role of the impurity.) The wavelength emitted by the emission center is dependent on the atom itself, its electronic configuration, and on the surrounding crystal structure.

The activators prolong the emission time (afterglow). In turn, other materials (such as nickel) can be used to quench the afterglow and shorten the decay part of the phosphor emission characteristics.

The electronic configuration of the activator depends on its oxidation state and is crucial for the light emission. Oxidation of the activator is one of the common mechanisms of phosphor degradation. The distribution of the activator in the crystal is also of high importance. Diffusion of the ions can cause depletion of the crystal from the activators with resulting loss of efficiency. This is another mechanism of phosphor degradation.

Burning (Maria Arredondo song)

"Burning" is the second single released from Maria Arredondo's album Not Going Under. It was released in September 2004 and was the second Arredondo single to become a video.

Track listing

Norwegian radio single

Lyrics

Passion is sweet
Love makes weak
You said you cherished freedom so
You refused to let it go

Follow your faith
Love and hate
never failed to seize the day
Don't give yourself away

Oh when the night falls
And your all alone
In your deepest sleep
What are you dreaming of

My skin's still burning from your touch
Oh I just can't get enough
I said I wouldn't ask for much
But your eyes are dangerous
So the thought keeps spinning in my head
Can we drop this masquerade
I can't predict where it ends
If you're the rock I'll crush against

Trapped in a crowd
Music's loud
I said I loved my freedom too
Now im not so sure i do

All eyes on you
Wings so true
Better quit while your ahead
Now I'm not so sure i am

Oh when the night falls
And your all alone
In your deepest sleep
What are you dreaming of

My skin's still burning from your touch
Oh I just can't get enough
I said I wouldn't ask for much
But your eyes are dangerous
So the thought keeps spinning in my head
Can we drop this masquerade
I can't predict where it ends
If you're the rock I'll crush against

My soul, my heart
If your near or if your far
My life, my love
You can have it all

Oh when the night falls
And your all alone
In your deepest sleep
What are you dreaming of

My skin's still burning from your touch
Oh I just can't get enough
I said I wouldn't ask for much
But your eyes are dangerous
So the thought keeps spinning in my head
Can we drop this masquerade
I can't predict where it ends
If you're the rock I'll crush against

If you're the rock I'll crush against

Combustion

Combustion /kəmˈbʌs.tʃən/ or burning is a high-temperature exothermic redox chemical reaction between a fuel and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combustion in a fire produces a flame, and the heat produced can make combustion self-sustaining. Combustion is often a complicated sequence of elementary radical reactions. Solid fuels, such as wood, first undergo endothermic pyrolysis to produce gaseous fuels whose combustion then supplies the heat required to produce more of them. Combustion is often hot enough that light in the form of either glowing or a flame is produced. A simple example can be seen in the combustion of hydrogen and oxygen into water vapor, a reaction commonly used to fuel rocket engines. This reaction releases 242 kJ/mol of heat and reduces the enthalpy accordingly (at constant temperature and pressure):

Combustion of an organic fuel in air is always exothermic because the double bond in O₂ is much weaker than other double bonds or pairs of single bonds, and therefore the formation of the stronger bonds in the combustion products CO₂ and H₂O results in the release of energy. The bond energies in the fuel play only a minor role, since they are similar to those in the combustion products; e.g., the sum of the bond energies of CH₄ is nearly the same as that of CO₂. The heat of combustion is approximately -418 kJ per mole of O₂ used up in the combustion reaction, and can be estimated from the elemental composition of the fuel.

The Belle Stars (album)

The Belle Stars is the only studio album by the all-female band of the same name released in 1983 (see 1983 in music). The band's eponymous debut album reached number 15 on the UK Albums Chart. The Belle Stars had some success with their single "Iko Iko", a cover of The Dixie Cups' 1965 hit. It charted at number 35 in June 1982 on the UK Singles Chart. Seven years later the song became a hit on the Billboard Hot 100 chart after it was featured in the movie Rain Man, where it peaked at number 14.

Track listing

All songs by The Belle Stars unless noted.