# 3-fold

**3-fold**is a tautogram (all words start with the same letter). View more tautograms!

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## Explanation

**3-fold**: In algebraic geometry, a 3-fold or threefold is a 3-dimensional algebraic variety.

## Printed dictionaries and other books with definitions for 3-fold

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### Topology and Geometry (2002)

Commemorating SISTAG : Singapore International Symposium in Topology and Geometry, (SISTAG) July 2-6, 2001, National University of Singapore, Singapore by A. Jon Berrick, Man Chun Leung, Xingwang Xu

and generalises them to indecomposable Gorenstein Fano 3-folds (see below
for explanation). DEFINITION 2.1. * A nonsingular Fano 3-fold is a nonsingular
irreducible projective variety of dimension 3 with ample –Ky*. Likewise, a
Gorenstein ...

### Quasiconformal Mappings and Analysis (2012)

A Collection of Papers Honoring F.W. Gehring by Peter Duren, Juha Heinonen, Brad Osgood, Bruce Palka

hyperbolic * 3-fold is a topological invariant*.
Because...

### A Theory of Generalized Donaldson-Thomas Invariants (2012)

by Dominic D. Joyce, Yinan Song

4, * a Calabi–Yau 3-fold is a smooth projective 3-fold X over K, with trivial
canonical bundle KX*. Fix a very ample line bundle OX (1) on X, and let (τ, G,⩽) ...

### Concise Encyclopedia Chemistry (1994)

by Mary Eagleson

Crystallographic symmetry operations Symmetry operation Symmetry element
Hermann- Mauguin symbol || 2-fold rotation **3-fold** rotation 4-fold rotation 6-fold
rotation Inversion (reflection through a point) Reflection **3-fold** rotary inversion ...

### Encyclopedia of toxicology (2005)

Dib-L] by Philip Wexler, Bruce D. Anderson

malate dehydrogenase (2–**3-fold**), phosphoglucose isomerase (2–**3-fold**),
glutathione ...

### Encyclopedia of Cancer (2011)

by Manfred Schwab

5- **to 3-fold** in overweight and obese
individuals. The > incidence rates of adenocarcinoma of the esophagus and
gastric cardia have been rapidly increasing in developed countries over the last ...

### Concise Dictionary of Materials Science (2002)

Structure and Characterization of Polycrystalline Materials by Vladimir Novikov

two perpendicular mirror planes; tetragonal, a single 4-fold axis or a
rotationinversion axis; rhombohedral, **a single 3-fold** axis or a rotation-inversion
axis; hexagonal, a single 6-fold axis or a rotation-inversion axis; and cubic, four 3
-fold axes.

### The Facts on File Dictionary of Earth Science (2009)

by Jacqueline Smith

triad
hexadaxisofrotationsymmetry (**3-fold**), tetrad(4-fold), and hexad (6-fold) planesof
Fig.1 axes respectively(fig.2). 3.center of sym- symmetry Fig.2 metry – a central
point aboutwhichevery ...

### A Dictionary of Geology and Earth Sciences (2013)

by Michael Allaby

**3-fold** (triad), 4-fold (tetrad), and 6
-fold (hexad) axes. The centre of symmetry is a central point which is present
when all faces or edges occur in parallel pairs on opposite sides of the crystal.

## Online dictionaries and encyclopedias with entries for 3-fold

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## Quotes about 3-fold

The safest way to double your money is to fold over once and put it in your pocket. (Kin Hubbard)*more quotes about 3-fold...*

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