Chemistry
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At the present time, Cyc's representation of scientific
chemistry is limited to certain basic relations between atoms,
molecules, and substances. Most representations of complex
substances in Cyc do not include chemical structures and
formulae, or the axioms to reason about them. Rather,
substances and their properties are represented at a more
"everyday" level: creation, destruction, changes, and
interactions are described and reasoned about, but the
underlying mechanisms are not usually considered.We have
resisted the temptation to assert many detailed, ready-made
axioms based on chemical reference material listing atomic
weights, electronegativity values, chemical formulae, etc.,
because devising the supporting theoretical axioms to use those
facts is neither easy nor of obvious value. Such is the case
with many fundamental theories in science: connecting them to
the real world is so hard that most scientific problems are
solved by invoking more specific rules which apply to different
kinds of situations.The following constants and the
representational techniques they embody may serve as a starting
point for more complete representations of chemical substances
as well as a more comprehensive chemical theory. For example,
the functional specification of types of atoms and nuclei can be
extended to cover isotopes.
Elements And Atoms
#$ElementStuff chemical elements
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of tangible substances; a
subcollection of #$InanimateThing.
Every instance of #$ElementStuff
is a piece of tangible stuff, composed of a quantity of
atoms, all of which are of the same chemical element. That
is, every atom in an individual piece of #$ElementStuff
has the same number of protons in its atomic nucleus as does
every other atom in that piece. For example, all pieces of
carbon are instances of #$ElementStuff.
All pieces of two of #$Carbon's subcollections, #$Diamond
and #$Graphite, also are instances of #$ElementStuff.
On the other hand, instances of #$Water, because they are
constituted of both (some) #$Hydrogen and (some) #$Oxygen
atoms, do not belong to the collection #$ElementStuff.
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direct instance of:
#$TangibleStuffCompositionType
direct specialization of:
#$InanimateThing
direct generalization of:
#$UnalloyedMetal
#$NobleGas
#$ElementStuffTypeByNumberOfProtons types
of chemical element classified by number of protons
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of collections. #$ElementStuffTypeByNumberOfProtons
partitions the collection #$ElementStuff.
Each instance of #$ElementStuffTypeByNumberOfProtons
is a subset of #$ElementStuff
which is defined ONLY by the atomic composition of its
instances -- neither the isotopic composition or physical
state of the substances, nor any other additional feature,
determines membership in a collection which #$isa #$ElementStuffTypeByNumberOfProtons.
All that matters is that the instances of that type (i.e.,
collection) of stuff are entirely composed of atoms having a
particular number of protons in each atomic nucleus. Thus,
the collection #$Carbon is an instance of #$ElementStuffTypeByNumberOfProtons,
but neither the collection #$Diamond nor the collection
#$Graphite is (even though they are subcollections of
#$Carbon), because their members have additional qualifications.
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direct instance of: #$SecondOrderCollection
#$DisjointCollectionType
direct specialization of:
#$ChemicalCompoundType #$ElementStuffType
#$atomicNumber atomic number
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
The predicate #$atomicNumber
indicates the atomic number of a type of element. (#$atomicNumber
E N) means that E, a collection belonging to #$ElementStuffTypeByNumberOfProtons,
has the positive integer N for its atomic number. This means
that any instance of (#$AtomFn E) must
have N #$Protons
in its #$AtomicNucleus.
For example, (#$atomicNumber
#$Carbon 6), and every instance of (#$AtomFn #$Carbon)
has six protons in its nucleus.
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direct instance of:
#$FunctionalSlot
#$AtomFn atom fn
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
An instance of #$CollectionDenotingFunction.
#$AtomFn may
be used to denote any subcollection of #$Atom which contains
all the atoms of a particular element type. #$AtomFn takes an
instance of #$ElementStuffTypeByNumberOfProtons
as its single argument and returns the collection of all
atoms of that element. Thus, for any E which is an #$ElementStuffTypeByNumberOfProtons,
(#$AtomFn E)
returns the subcollection of #$Atom which contains
all the atoms of element type E. Each atom in the collection
(#$AtomFn E)
has N protons in its atomic nucleus, where N is the #$atomicNumber
of the element type E. For example, (#$AtomFn #$Carbon)
is the collection of carbon atoms, each of which has 6
protons in its nucleus.
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direct instance of:
#$CollectionDenotingFunction
#$UnaryFunction #$ReifiableFunction
#$Individual
#$Atom atoms
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of microscopic-scale objects. Each
instance of #$Atom
has one atomic nucleus and some number of electrons. As a
default, we assume that an instance of #$Atom has no net
charge, i.e., that it has as many instances of #$Electrons as it
does of #$Protons in its #$AtomicNucleus;
but note there are exceptions, e.g., those which are
instances of #$Ion.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$ChemicalObject
#$NucleusFn nucleus fn
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
#$NucleusFn is a
Cyc function, specifically a #$CollectionDenotingFunction.
#$NucleusFn
takes an instance of #$ElementStuffTypeByNumberOfProtons
(q.v.) as its single argument and returns a collection of
all the atomic nucleii belonging to element-stuff of that
type. Thus, (#$NucleusFn E)
denotes a subcollection of #$AtomicNucleus
whose elements all have the same number of protons. For
example, (#$NucleusFn
#$Carbon) is the collection of #$Carbon nuclei, each of
which has six protons.
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direct instance of: #$UnaryFunction #$CollectionDenotingFunction
#$ReifiableFunction
#$Individual
#$AtomicNucleus atomic nuclei
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of objects; a subcollection of #$MicroscopicScaleObject.
Each instance of #$AtomicNucleus
is an object composed of some definite number of instances
of #$Proton and
some definite number of instances of #$Neutron.
Instances of the collection #$Atom are each
composed of one member of #$AtomicNucleus
and some number of electrons.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$MicroscopicScaleObject
Sub
#$SubAtomicParticle subatomic particles
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of objects; a subcollection of #$MicroscopicScaleObject.
Every instance of #$SubAtomicParticle
is a physical particle smaller than an atom. Major
subcollections of #$SubAtomicParticle
include #$Electron, #$Proton, and #$Neutron.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$MicroscopicScaleObject #$InanimateObject-Natural
direct generalization of:
#$Nucleon #$Electron
#$Electron electrons
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of objects; a subcollection of #$SubAtomicParticle.
Every instance of #$Electron is a
subatomic particle with an #$ElectricalCharge
of -1.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$SubAtomicParticle
#$Nucleon nucleons
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of objects; a subcollection of #$SubAtomicParticle.
Each instance of #$Nucleon is a
subatomic particle normally found in some atomic nucleus. #$Nucleon has two
subcollections, #$Proton and #$Neutron. Every
instance of #$AtomicNucleus
is composed of some number of #$Nucleons.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$SubAtomicParticle
direct generalization of:
#$Neutron #$Proton
#$Proton protons
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of objects; a subcollection of #$Nucleon. Each
instance of #$Proton is a
nucleon which has an #$ElectricalCharge
of +1.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$Nucleon
#$Neutron neutrons
A specialization of #$Nucleon. Each
instance of #$Neutron is a
nucleon with an electrical charge of 0.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$Nucleon
Chemical Compounds Molecules
#$ChemicalObject chemical objects
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A specialization of #$MicroscopicScaleObject.
Each instance of #$ChemicalObject
is an object whose behavior is typically described in terms
of its outer cloud of #$Electrons.
Specializations of #$ChemicalObject
include the collections #$Atom, #$Molecule, and
#$Ion.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$MicroscopicScaleObject
direct generalization of:
#$Molecule #$Atom
#$Molecule molecules
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of microscopic-scale objects; a
subcollection of #$ChemicalObject.
Every instance of #$Molecule is a
microscopic object whose component atoms are all chemically
bonded to each other; typically, this means that the atoms
are covalently bonded. Examples: some instances of #$Molecule,
including molecules of oxygen (O2), ozone (O3), water (H2O),
carbon monoxide (CO), carbon dioxide (CO2), etc., contain
covalently bonded atoms belonging to the collection
#$Oxygen. Some highly complex examples of #$Molecule are
those belonging to the collection #$DNAMolecule. See also #$MoleculeFn.
Note: #$Diamond and other macroscopic covalent solids are
excluded from belonging to #$Molecule by the
constraint that instances of #$Molecule are microscopic.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$ComplexPhysicalObject #$ChemicalObject
#$Ion ions
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of microscopic-scale objects; a subset
of #$ChemicalObject.
Every instance of #$Ion is an atom or
radical which has either a negative or positive net
electrical charge, due to having either more or fewer
electrons than there are protons in its nuclei. Note: atomic
ions violate Cyc's default assumption that instances of #$Atom have a net
electrical charge of zero, so #$Ion constitutes a
class of exceptions to that rule.
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direct instance of:
#$ExistingObjectType
direct specialization of:
#$ChemicalObject
#$ChemicalCompoundType chemical compounds
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of collections; a specialization of #$TangibleStuffCompositionType.
Every instance of #$ChemicalCompoundType
is a specialization of #$PartiallyTangible
whose instances are defined ONLY by their chemical
composition, and not by their physical state or any other
property. In Cyc's current representation, #$ChemicalCompoundTypes
can be of two varieties: (1) Collections whose instances are
completely uniform with each other in terms of chemical
composition; this includes (a) the chemical elements -- such
as #$Carbon, #$Oxygen, and #$Hydrogen -- which are instances
of #$ElementStuffTypeByNumberOfProtons
(thus, the latter is a specialization of #$ChemicalCompoundType),
and (b) compounds constituted of more than one substance
chemically bonded, e.g., #$Water, #$Caffeine, and
#$IronOxide. (2) Substances which have a general chemical
specification, that is, whose instances do not have exactly
the same chemical composition but fall within certain
specifications, e.g., #$DNAStuff. Cyc's current theory
includes those cases in #$ChemicalCompoundType,
though they are arguably borderline. (Future work may
require the creation of type collections to identify various
levels of chemical specification, such as `exact formula' or
`exact structure'.) Note: Collections which Cyc does NOT
classify as #$ChemicalCompoundTypes
include collections of substances which have some component
which is of overriding significance in some context, so that
in everyday language such substances are frequently referred
to by the name of their important component (e.g.,
`penicillin' applied to a tablet containing penicillin), but
which have significant admixtures of other substances. Our
representation distinguishes between the chemical compound
(here, instances of #$Penicillin) and the mixture of
substances in a tablet containing some #$Penicillin for
pharmaceutical use. Thus, #$Penicillin is an instance of #$ChemicalCompoundType,
but the collection of tablets containing penicillin and
including other ingredients are not. Also, specializations
of #$Mixture,
such as #$Lemonade, are not instances of #$ChemicalCompoundType,
because mixtures are determined by their physical state
rather than solely by their chemical composition.
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direct instance of:
#$SiblingDisjointCollection
#$SecondOrderCollection
direct specialization of:
#$TangibleStuffCompositionType
direct generalization of:
#$ElementStuffTypeByNumberOfProtons
#$MolecularStuff molecular stuff
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of tangible stuff. Every instance of
#$MolecularStuff
is a portion of stuff composed of covalently-bonded
molecules. Thus, #$Water and #$DNAStuff are subcollections
of #$MolecularStuff;
each of their instances consists of covalently bonded
molecules. But instances of #$Salt-NaCl are not examples of
#$MolecularStuff.
Also, #$Oxygen is not a subcollection of #$MolecularStuff,
since #$Oxygen denotes anything composed of that element,
not just O2 (molecular oxygen) and O3 (ozone).
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direct instance of:
#$TangibleStuffCompositionType
direct specialization of:
#$PartiallyTangible
#$MoleculeFn molecule fn
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
#$MoleculeFn is
a Cyc function, specifically a #$CollectionDenotingFunction.
It takes an instance of #$ChemicalCompoundType
as its sole argument and returns the set of all molecules of
that compound. (#$MoleculeFn
X) denotes the collection of all #$Molecules of #$MolecularStuff
X. For example, (#$MoleculeFn
#$Water) is the collection of all water molecules.
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direct instance of: #$UnaryFunction #$CollectionDenotingFunction
#$MacroRelation #$ReifiableFunction
#$Individual
#$MicroscopicScaleObject microscopic objects
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A specialization of #$PartiallyTangible.
Each instance of #$MicroscopicScaleObject
is a partially tangible object which is so small that human
beings cannot perceive it, except (perhaps) with the use of
special devices such as electron microscopes.
Specializations of #$MicroscopicScaleObject
include #$Molecule, #$Atom, #$SubAtomicParticle,
#$Chloroplast, and #$Mitochondrion.
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direct instance of:
#$TemporalStuffType
direct specialization of:
#$PartiallyTangible
direct generalization of:
#$SubAtomicParticle
#$ChemicalObject
#$AtomicNucleus
#$CellPart
#$Microorganism
Metal
#$Metal metallic elements
**GAFs NOT REVIEWED**
An instance of #$TangibleStuffCompositionType.
Every instance of #$Metal is a
tangible object having certain characteristic physical and
chemical properties. Instances of #$Metal are good
conductors of electricity and heat, and most instances of #$Metal are solids
at room temperature (although all instances of #$Mercury,
for example, are liquids at room temperature). Solid
instances of #$Metal have a shiny
luster, and are highly malleable. Specializations of #$Metal includes
#$Mercury, #$Potassium, #$Brass, #$Lead, and #$Iron.
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direct instance of: #$ProductByGenericType #$TangibleStuffCompositionType
direct specialization of:
#$ElectricalConductor #$InorganicStuff
direct generalization of:
#$UnalloyedMetal
#$MetalAlloy
#$MetalAlloy alloys
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of tangible stuffs; a subcollection of
#$Metal. Each
instance of #$MetalAlloy is
a metallic stuff which is a homogeneous blend of at least
one part of #$UnalloyedMetal
with at least one other substance. #$MetalAlloy is
not a subcollection of #$Mixture,
because each instance of #$MetalAlloy is
defined not only by the amounts and kinds of its #$constituents,
but also (unlike a mixture) by the internal structures
formed during its creation. Furthermore, the creation
process is typically more complex than #$Mixing. Common
metal alloys include the instances of #$Bronze-Stuff,
#$Brass, and #$Steel. Note that #$GalvanizedMetal is NOT a
subcollection of #$MetalAlloy,
because every instance of #$GalvanizedMetal has a coating of
some #$Zinc on its surface, and thus (unlike an alloy) the
components of galvanized metals are not homogenously
distributed throughout.
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direct instance of:
#$TangibleStuffCompositionType
direct specialization of:
#$Mixture #$ArtificialMaterial #$Metal
#$UnalloyedMetal unalloyed metals
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of tangible stuffs; a subcollection of
#$Metal.
Every instance of #$UnalloyedMetal
is a metal which is also an element, i.e., a substance of
unmixed chemical type. Thus, each subcollection of #$UnalloyedMetal
is a subcollection of both #$Metal and #$ElementStuff.
Examples of #$UnalloyedMetal
include #$Gold, #$Iron, #$Uranium, #$Antimony, #$Titanium,
and many more.
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direct instance of:
#$TangibleStuffCompositionType
direct specialization of:
#$Metal #$ElementStuff
#$NobleGas inert gases
A specialization of #$ElementStuff.
Each specialization of #$NobleGas is a
type of element that does _not_ readily form compounds with
other types of elements. Instances of #$NobleGas are
highly stable, due to the fact that they have the maximum
number of electrons possible in their outer shell. The six
specializations of #$NobleGas are
#$Helium, #$Neon, #$Argon, #$Krypton, #$Xenon, and #$Radon.
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direct instance of:
#$TangibleStuffCompositionType
direct specialization of:
#$ElementStuff
Chemical Reactions
#$ChemicalReaction chemical reactions
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of events; a subcollection of #$TransformationEvent.
Each instance of #$ChemicalReaction
is an event in which two or more substances undergo a
chemical change, i.e., some portions of the substances
involved are transformed into different #$ChemicalCompoundTypes.
The transformations are brought about by purely chemical
(including biochemical) means which affect chemical bonds
between atoms in the molecules of stuff, rather than by
physical means, biological means, or purposeful planning,
etc. Examples of #$ChemicalReaction:
instances of #$CombustionProcess;
instances of #$Photosynthesis-Generic.
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direct instance of:
#$TemporalObjectType
#$DefaultDisjointScriptType
direct specialization of:
#$ChemicalInteraction #$TransformationEvent
#$catalyst catalyzer
(actor slot)
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
The predicate #$catalyst
identifies the particular thing that acts as a catalyst in a
particular chemical reaction. (#$catalyst R X)
means that the #$ChemicalReaction
R has the particular quantity of substance X as a catalyst.
For example, every instance of #$Photosynthesis-Generic has
some portion of #$Chlorophyll as a catalyst; an amount of
#$Water may be a #$catalyst in
some #$OxidationProcess
of a #$Metal.
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direct instance of: #$IndividualLevelPredicate #$ActorSlot
direct specialization of: #$unchangedActors
Purity
#$PureFn pure fn
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
An instance of #$CollectionDenotingFunction.
(#$PureFn X)
denotes the subcollection of the #$ChemicalCompoundType
X whose instances are chemically pure. Note that #$PureFn can be
applied only to instances of #$ChemicalCompoundType
(such as #$Fructose or #$Water), but not to mixtures (such
as #$Air). See also #$PureCompound.
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direct instance of: #$UnaryIntersectionFunction #$Individual
#$PureCompound pure compounds
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of tangible stuffs. Each instance of
#$PureCompound
is a chemically pure portion of stuff belonging to some
particular #$ChemicalCompoundType
(e.g., #$Carbon, #$Water, #$Cellulose ). `Chemically pure'
applies to a piece of stuff which has no sub-portions that
fail to conform to the chemical composition of its (single)
#$ChemicalCompoundType.
In typical contexts, most common portions of a #$ChemicalCompoundType
will not be instances of #$PureCompound
. For example, a piece of pencil lead, though mostly carbon,
will not be an instance since it is not pure carbon and any
portion of ordinary tap water will contain too many
impurities. Many sub-portions of either a piece of pencil
lead or portion of tap water will fail to conform to the
chemical composition of either carbon or water. Some
instances of #$ChemicalCompoundType
are subcollections of #$PureCompound
in most contexts but not in all. In typical domestic
contexts, for example, a piece of ordinary distilled water
would be an instance of #$PureCompound
. However, in a clean room or microchip manufacturing
context, ordinary distilled water would probably be
considerd impure (see #$ImpureCompound). In general, to
refer to a pure instance of a substance one can use the
function #$PureFn, e.g. (#$PureFn
#$Carbon). Note that #$PureFn has #$PureCompound
as a #$resultGenl
. Since this kind of purity is relative to specified
chemical composition only, #$PureCompound
(and #$PureFn)
does not pertain to mixtures in Cyc (such as #$Air). Cf. #$Mixture, #$ChemicalCompoundType.
See also #$PureCompoundType
and #$ImpureCompound.
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direct instance of:
#$TangibleStuffCompositionType
direct specialization of:
#$InanimateThing
#$PureCompoundType types
of pure chemical compound
**COMMENT NOT REVIEWED**
**GAFs NOT REVIEWED**
A collection of collections. Every instance of #$PureCompoundType
is a collection which is a subcollection of both #$PureCompound
and of some particular #$ChemicalCompoundType
(e.g., #$Carbon, #$Water, #$Cellulose). Each instance of #$PureCompoundType
is defined ONLY by the properties of its #$ChemicalCompoundType,
and of #$PureCompound
(q.v.). For example, (#$PureFn
#$Fructose) is an instance of #$PureCompoundType,
but the subcollections of #$Fructose, such as (say) `pure
fructose derived from honey' would not be instances of #$PureCompoundType.
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direct instance of: #$SecondOrderCollection
direct specialization of:
#$TangibleStuffCompositionType
Copyright© 1996-2002. All rights reserved. See Terms of Usage.