system of units. Such a set requires
three mechanical units (usually of
length, mass, and time) and one electrical unit; it has also been found
convenient to treat certain other
quantities as fundamental, even
though they are not strictly independent. In the metric system the
centimetre–gram–second (c.g.s.)
system was replaced by the metre–
kilogram–second (m.k.s.) system; the
latter has now been adapted to provide the basis for *SI units. In British
Imperial units the foot–pound–
second (f.p.s.) system was formerly
used.
fungicide See pesticide.
furan A colourless liquid compound, C 4 H 4 O; r.d. 0.94; m.p. –86°C;
b.p. 31.4°C. It has a Üve-membered
ring consisting of four CH 2 groups
and one oxygen atom.
239
fusion
f
O
Furan
furanose A *sugar having a Üvemembered ring containing four carbon atoms and one oxygen atom.
furfural A colourless liquid,
C 5 H 4 O 2 , b.p. 162°C, which darkens
on standing in air. It is the aldehyde
derivative of *furan and occurs in
various essential oils and in *fusel
oil. It is used as a solvent for extracting mineral oils and natural resins
and itself forms resins with some
aromatic compounds.
fused ring See ring.
A
• Information about IUPAC nomenclature
fusel oil A mixture of highmolecular weight *alcohols containing also esters and fatty acids, sometimes formed as a toxic impurity in
the distillation products of alcoholic
fermentation. It is used as a source of
higher alcohols and in making paints
and plastics.
fusible alloys Alloys that melt at
low temperature (around 100°C).
They have a number of uses, including constant-temperature baths, pipe
bending, and automatic sprinklers to
provide a spray of water to prevent
Üres from spreading. Fusible alloys
are usually *eutectic mixtures of bismuth, lead, tin, and cadmium.
*Wood’s metal, *Rose’s metal, and
Lipowitz’s alloy are examples of alloys that melt in the range 70–100°C.
fusion Melting.
www.AzShimi.ir www.AzShimi.com
three mechanical units (usually of
length, mass, and time) and one electrical unit; it has also been found
convenient to treat certain other
quantities as fundamental, even
though they are not strictly independent. In the metric system the
centimetre–gram–second (c.g.s.)
system was replaced by the metre–
kilogram–second (m.k.s.) system; the
latter has now been adapted to provide the basis for *SI units. In British
Imperial units the foot–pound–
second (f.p.s.) system was formerly
used.
fungicide See pesticide.
furan A colourless liquid compound, C 4 H 4 O; r.d. 0.94; m.p. –86°C;
b.p. 31.4°C. It has a Üve-membered
ring consisting of four CH 2 groups
and one oxygen atom.
239
fusion
f
O
Furan
furanose A *sugar having a Üvemembered ring containing four carbon atoms and one oxygen atom.
furfural A colourless liquid,
C 5 H 4 O 2 , b.p. 162°C, which darkens
on standing in air. It is the aldehyde
derivative of *furan and occurs in
various essential oils and in *fusel
oil. It is used as a solvent for extracting mineral oils and natural resins
and itself forms resins with some
aromatic compounds.
fused ring See ring.
A
• Information about IUPAC nomenclature
fusel oil A mixture of highmolecular weight *alcohols containing also esters and fatty acids, sometimes formed as a toxic impurity in
the distillation products of alcoholic
fermentation. It is used as a source of
higher alcohols and in making paints
and plastics.
fusible alloys Alloys that melt at
low temperature (around 100°C).
They have a number of uses, including constant-temperature baths, pipe
bending, and automatic sprinklers to
provide a spray of water to prevent
Üres from spreading. Fusible alloys
are usually *eutectic mixtures of bismuth, lead, tin, and cadmium.
*Wood’s metal, *Rose’s metal, and
Lipowitz’s alloy are examples of alloys that melt in the range 70–100°C.
fusion Melting.
www.AzShimi.ir www.AzShimi.com