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year of the
rabbit
’
The
‘
year
of
the
rabbit
’
is
China
first
lunar
rover,
on
November
26,
2013
morning
9
when
make,
industry
of
national
defence science and
Technology Bureau held a press conference,
announced the
lunar
surface
vacuum,
strong
radiation,
minus
180
degrees
Celsius
to
150
degrees
above
zero
temperature
limit
of
the
extreme
environment.
The
lunar
rover
with
20
degrees,
20
cm
of
climbing
obstacle
capability,
and
is
equipped
with
a
panoramic
camera,
infrared
imaging
spectrometer,
moon
radar,
particle
induced
X
ray
spectrometer
and
other
scientific
detection instrument.
Shoulder two can open the solar panels,
her leg is mobile device of six wheel shaped,
development of dozens of programs,
researchers had produced four wheel, six wheel,
eight wheel and crawler type etc..
Finally, determining the drive for
one more month dialogue communication
antenna; obstacle avoiding the overhead camera
navigation camera before and
after the party; responsible for
drilling, grinding and sampling mechanical
arm.
High temperature
resistant materials
High
temperature
resistant
materials
including
refractory
and
heat
resistant
materials,
inorganic
compounds,
there
are
polymer
materials.
Refractory
material usually refers to the temperature above
1580
℃
inorganic materials.
They were built furnace, combustion
chamber and other high temperature
resistant building materials. General use of
quartz sand, clay, magnesite, dolomite as
raw material, high temperature
insulation coating Zhi Sheng, is a component of
inorganic coatings, high temperature in the
range of -80 - 1800
℃
, heat conduction
coefficient is 0.03W/m.K, the thermal radiation
and conduction heat can inhibit the
object
of
high
temperature
and
low
temperature
object,
for
the
high
temperature
object
to
keep
70%
of
the
heat
loss.
Zhisheng
coating
on
the
surface
of
an
object
with
8mm
at
1100
℃
high
temperature
insulation
coating,
the
surface
temperature can be
decreased from 1100
℃
to 100
℃
. In
addition
to
high
temperature
insulation
characteristic
of
coating
and
insulation,
light
weight,
convenient
construction,
long
service
life,
heat
insulation,
can
also
be
used
for
inorganic
materials,
high
temperature
resistant
adhesives
using
object
firmly,
attachment.
Such
as
refractory
cement,
magnesia
brick
etc..
Broadly
speaking,
the
inorganic
fireproof,
heat
resistant
materials
refers
to
these
compounds,
high
hardness,
brittleness,
good
resistance
to
chemical corrosion, and
the melting point is in 1500 above,
such
as
high
temperature
glass,
also belongs to the refractory
material.
Constituent structure
The
main
points
of
metal
and
non
metal
compound
and
non
intermetallic
compound
two.
The
former
such
as
tungsten,
molybdenum, tantalum, niobium,
vanadium, chromium, titanium, zirconium and other
refractory metal and rare earth metal
borides, carbides, nitrides, silicides,
phosphide and sulfides; if the latter boron
carbide, silicon carbide, boron nitride, silicon
nitride, boron phosphide, silicon
phosphide etc.. The latter has very important use,
can be used as refractory materials (such
as
abrasive,
mold
temperature,
nozzle,
thermowell),
heat
resistant
materials
(structural
elements,
such
as
rocket
nuclear
engineering
material, electric heating element), electrical
materials (such as high temperature thermocouple,
ignitor), also
used as chemical
resistant materials and hard materials etc.. Heat
resistant polymers can be used as high temperature
film
insulation
of
high
temperature
resistant
fiber,
high
temperature
resistant
coating,
high
temperature
resistant
adhesive
material, etc.. According to the high
temperature time, and instantaneous high
temperature resistant material and long time
high temperature resistant materials.
The former in 1000 ~ 10000
℃
a few seconds to a few minutes. The ablative
material is
high temperature resistant
materials. For example, in the 300 ~ 600
℃
, in the air, it can
maintain the mechanical strength and
chemical resistance
Beidou satellite navigation
system
Beidou satellite
navigation system will BeiDou Navigation Satellite
System, abbreviated as BDS: is China being
implemented
The
Beidou
satellite
navigation
Global navigation
satellite system of
operation,
abbreviated
as
BDS[2-3],
compatible
with
global
satellite
satellite
navigation
system.
Beidou
continuous
navigation
and
time
system
independent
research
and
development,
independent
Galileo
and
America
GPS,
the
Russian
GLONASS,
EU
navigation
system,
shared,
and
said
the
four
major
global
satellite
navigation
system
in
December
27,
2011
to
provide
service
Beidou
satellite
navigation
system
consists of a space,
the ground end and customer end of three
parts. The
spatial
side
consists
of
5
geostationary
orbit
satellite
and
30
non
geostationary
orbit
satellite. The
ground end