| slovo | definícia |
boron
(encz) | boron,bór n: Zdeněk Brož |
Boron
(gcide) | Boron \Bo"ron\ (b[=o]"r[o^]n), n. [See Borax.] (Chem.)
A nonmetallic element occurring abundantly in borax. It is
reduced with difficulty to the free state, when it can be
obtained in several different forms; viz., as a substance of
a deep olive color, in a semimetallic form, and in colorless
quadratic crystals similar to the diamond in hardness and
other properties. It occurs in nature also in boracite,
datolite, tourmaline, and some other minerals. Atomic number
5. Atomic weight 10.81. Symbol B.
[1913 Webster] |
boron
(wn) | boron
n 1: a trivalent metalloid element; occurs both in a hard black
crystal and in the form of a yellow or brown powder [syn:
boron, B, atomic number 5] |
boron
(elements) | boron
Symbol: B
Atomic number: 5
Atomic weight: 10.811
An element of group 13 of the periodic table. There are two allotropes,
amorphous boron is a brown power, but metallic boron is black. The
metallic form is hard (9.3 on Mohs' scale) and a bad conductor in room
temperatures. It is never found free in nature. Boron-10 is used in
nuclear reactor control rods and shields. It was discovered in 1808 by
Sir
Humphry Davy and by J.L. Gay-Lussac and L.J. Thenard.
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| | podobné slovo | definícia |
gaborone
(encz) | Gaborone,hl.m. - Botswana n: [jmén.] [zem.] Zdeněk Brož a automatický
překlad |
Boron
(gcide) | Boron \Bo"ron\ (b[=o]"r[o^]n), n. [See Borax.] (Chem.)
A nonmetallic element occurring abundantly in borax. It is
reduced with difficulty to the free state, when it can be
obtained in several different forms; viz., as a substance of
a deep olive color, in a semimetallic form, and in colorless
quadratic crystals similar to the diamond in hardness and
other properties. It occurs in nature also in boracite,
datolite, tourmaline, and some other minerals. Atomic number
5. Atomic weight 10.81. Symbol B.
[1913 Webster] |
boronic
(gcide) | boronic \bo*ron"ic\ adj.
of or pertaining to boron.
[WordNet 1.5] |
ekaboron
(gcide) | Scandium \Scan"di*um\, n. [NL. So called because found in
Scandinavian minerals.] (Chem.)
A rare metallic element of the boron group, whose existence
was predicted under the provisional name ekaboron by means
of the periodic law, and subsequently discovered by spectrum
analysis in certain rare Scandinavian minerals (euxenite and
gadolinite). It has not yet been isolated. Symbol Sc. Atomic
weight 44.
[1913 Webster]Ekabor \Ek"a*bor`\ ([e^]k"[.a]*b[=o]r`), Ekaboron \Ek"a*bo"ron\
(-b[=o]"r[o^]n), n. [G., fr. Skr. [=e]ka one + G. bor, boron,
E. boron.] (Chem.)
The name given by Mendelejeff in accordance with the periodic
law, and by prediction, to a hypothetical element then
unknown, but since discovered and named scandium; -- so
called because it was a missing analogue of the boron group.
See Scandium.
[1913 Webster] |
Ekaboron
(gcide) | Scandium \Scan"di*um\, n. [NL. So called because found in
Scandinavian minerals.] (Chem.)
A rare metallic element of the boron group, whose existence
was predicted under the provisional name ekaboron by means
of the periodic law, and subsequently discovered by spectrum
analysis in certain rare Scandinavian minerals (euxenite and
gadolinite). It has not yet been isolated. Symbol Sc. Atomic
weight 44.
[1913 Webster]Ekabor \Ek"a*bor`\ ([e^]k"[.a]*b[=o]r`), Ekaboron \Ek"a*bo"ron\
(-b[=o]"r[o^]n), n. [G., fr. Skr. [=e]ka one + G. bor, boron,
E. boron.] (Chem.)
The name given by Mendelejeff in accordance with the periodic
law, and by prediction, to a hypothetical element then
unknown, but since discovered and named scandium; -- so
called because it was a missing analogue of the boron group.
See Scandium.
[1913 Webster] |
boron chamber
(wn) | boron chamber
n 1: an ionization chamber lined with boron or filled with boron
trifluoride gas for counting low velocity neutrons |
boron counter tube
(wn) | boron counter tube
n 1: a proportional counter tube for counting neutrons |
boron trifluoride
(wn) | boron trifluoride
n 1: a pungent colorless gas |
boronic
(wn) | boronic
adj 1: of or relating to boron |
gaborone
(wn) | Gaborone
n 1: capital and largest city of Botswana in the extreme
southeast [syn: Gaborone, capital of Botswana] |
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