第1个回答 2010-01-23
Air pollution comes mainly from people's lives and production activities, the atmosphere There are three kinds of man-made sources.
(1) Life Source people as cooking, heating, bathing and other daily needs, such as stoves, boilers and other combustion of fossil fuels, emissions to the atmosphere such as soot and SO2, with large, widely distributed, high and low emissions characteristics, and its harmful consequences can not be ignored.
(2) Industrial sources of pollution, including power plants, steel mills, cement factories and chemical plants are more energy-intensive businesses such as emissions from fuel combustion, the production process of the exhaust (such as coking plant emission to the atmosphere H2S, phenols, benzene , hydrocarbons and other toxic substances; various types of chemical emissions into the atmosphere with the irritating, corrosive, odor or stench of organic and inorganic gases; chemical fiber plant emissions of H2S, NH3, CS2, methanol, acetone, etc.) as well as the production process emissions from a variety of mineral and metal dust.
(3) Transport sources of pollution from aircraft, ships, automobiles and other modes of transport (mobile sources) emissions of the exhaust. In some developed countries, automobile emissions from air pollution and pose a major source of pollution.
第3个回答 2020-05-29
the
Chinese
ancient
silk
hair
commonly
is
unique
JiZhong
place,
"color"
is
the
main
characters
commonly
silk
hair.
"Color"
phenotype
and
the
synthesis
of
melanin,
body
and
diffusion.
Silk
hair
tonic
and
medicinal
value
of
commonly
with
the
body
of
melanin.
Extensive
melanin
deposition
is
the
important
economic
characters
commonly
peculiar.
Silk
hair
melanin
is
in
commonly
tyrosine
nitration
under
the
action
of
enzyme,
after
a
series
of
biochemical
reactions,
which
formed
by
the
synthetic
genetic
control.
Phenylalanine
in
animals
can
phenylalanine)
under
the
action
of
the
enzyme
transformed,
phenylalanine
tyrosinase
in
a
certain
extent
can
also
be
converted
to
melanin.
Therefore,
tyrosine
and
phenylalanine
is
also
called
melanin
precursors
of
amino
acids.
But
the
silk
hair
grows
slowly,
weight
less
commonly,
egg
performance
is
poor,
meat
performance,
feed
conversion
rate
is
low,
cause
the
melanin
deposition
of
molecular
regulation
mechanism
of
complex.
Now
uriah
to
commonly
"color"
research
focuses
on
the
melanin,
distribution,
structure,
etc.
Researchers
in
the
phenotype,
commonly
silk
hair
melanin
production
performance
of
synthetic
gene
polymorphism
is
studied,
the
influence
of
the
synthesis
of
melanin,
but
genes
in
the
expression
and
regulation
commonly
silk
hair,
gene
expression
of
scheduling
aspects
of
commonly
reported
little
growth
stage
in
different
periods
and
organizational
melanin
gene
expression
"color"
traits
without
relevance;
For
fodder
for
melanin
synthesis
influence
amino
acids
from
molecular
Angle.
No
research
Therefore
it
is
necessary
in
molecular
biology
technology
of
silk
commonly
melanin
the
feather
expression
related
gene
expression
of
the
characters
of
the
regulation
on
study.
This
experiment
USES
four
phenylalanine,
tyrosine
level
of
diet
fed
commonly
0-16
weeks
silk
hair,
observation
and
measurement
of
its
growth
stages
commonly
silk
hair
performance,
biochemical,
and
simulated
the
silk
hair
growth
curve
commonly,
Through
comparison
of
growth
than
card
several
stages
of
each
part
of
the
appearance
of
black
degree
of
visualizing
and
records,
from
the
appearance
Discusses
the
melanin
deposition
distribution,
Using
fluorescence
detection
quantitative
polymerase
chain
reaction
(PCR)
for
the
synthesis
of
melanin
in
three
main
effect
genes
related
gene
(TYR)
tyrosinase,
enzymatic
related
proteins
(1)
and
TYRPI
melanoma
skin
quality
receptor
(1
MC1R)
in
different
organizations,
the
expression
differences,
from
weeks
gene
expression
studies
to
explore
the
melanin
level.
Main
research
results
are
as
follows:
1,
the
production
performance
of
silk
hair
commonly
results
show
that
diet
tyrosine,
phenylalanine
level
2,
6
significantly,
12,
14
weeks
of
weight,
significantly
influence
the
0-2,
5-6
and
11-16
weeks,
the
significant
influence
of
plecata
0-2,
3-4,
11-12
and
15-16
weeks
of
average
intake,
significantly
affect
3-8,
11-16
weeks
of
weight
ratio,
diet
tyrosine,
phenylalanine
level
in
0.43%
0.91
and
the
experimental
1.31%,
0.77%
and
showed
relatively
good
performance.
2,
using
logistic,
Bertalanffy
von
Gompertz,
three
models
of
pure
silk
hair
the
growth
of
commonly
curve
fitting
and
analysis,
the
result
shows
that
the
model
can
simulate
logistic
commonly
silk
hair
growth.
3
and
serum
biochemical
index
determination
commonly
silk
hair,
the
results
show
that:
the
diet
tyrosine,
phenylalanine
level
of
serum
biochemical
index
commonly
silk
hair,
and
other
significant
effects
on
the
glucose
various
biochemical
index
effects
were
not
significant.
Different
weeks
of
silk
hair
serum
biochemical
index
commonly
were
extremely
significant
influence.
4
and
diet
tyrosine,
phenylalanine
level
of
silk
hair
black
degrees
commonly
on
the
distribution
of
the
skin
and
muscle
tissue,
chest
has
significant
effects
on
the
distribution
of
black,
the
appearance
of
black
organization
has
significant
effects
on
the
distribution
of
the
trachea,
internal
organization
has
significant
effects
on
the
distribution
of
black,
the
digestive
tract
of
esophageal
black
distribution
very
significant
effect,
reproductive
tissue
testicular
black
distribution
very
significant
effect.
Different
weeks
of
silk
hair
organization
distribution
of
melanin
commonly,
most
significantly
influence
tissue.
Gender
distribution
of
silk
hair
black,
commonly,
tube
and
marrow,
keel
and
glandular
stomach
significantly
influence
etc.
5
and
diet
tyrosine,
phenylalanine
level
of
silk
hair
MC1R
gene,
commonly
in
the
organization
TYR
gene
expression,
liver,
and
were
extremely
significant
influence
Ⅲ
treatment
groups
are
the
highest,
treatment
group
Ⅰ
relatively
low,
with
tyrosine
and
phenylalanine
additives,
and
express
quantity
TYRP1
gene
expression
of
the
bone
marrow,
processing
Ⅱ
group
has
significant
effects
on
the
top,
with
Ⅰ
relatively
low,
Different
to
the
bone
in
weeks
silk
hair
MC1R
genes
and
gene
expression,
liver
TYR
very
significant
effect,
and
is
the
highest,
about
4
weeks
in
eight
weeks
when
the
minimum,
Different
to
the
bone
in
weeks
silk
hair
TYRP1
gene
expression,
liver
and
bone
marrow
were
significantly
influence
in
the
liver,
the
expression,
4
weeks,
16
weeks
left
when
the
lowest,
in
the
bone
marrow,
from
birth
to
eight
weeks
with
increasing
while
increasing
after
weeks
and
weeks
with
increasing
while
descending,
MC1R
TYR,
TYRP1
and
gene
expression
in
the
organization
commonly
silk
hair,
skin
and
bone
marrow,
etc,
to
organize
and
express
significantly
difference,
TYRP1
gene
expression
for
the
highest,
relatively
low
relative
TYR
gene
expression.
The
diet
of
silk
hair
commonly
added
phenylalanine
and
four
levels,
tyrosine
production
performance,
the
growth
curve
fitting,
biochemical,
black
degree
contrast,
melanin
aspects
related
gene
expression
in
the
research
and
analysis
on
the
basis
of
silk
hair
melanin
made
comprehensive
commonly,
to
control
the
effect
of
chicken
melanin
deposition
gene,
for
more
reasonable
exploitation
and
utilization
of
this
precious
commonly
poultry
resources
to
provide
certain
theoretical
basis
for
chicken,
human
and
animal
studies
as
a
model
of
birds
and
mammals
melanin
formation
of
molecular
mechanism
of
molecular
basis
etc,
and
through
different
time
commonly
melanin
deposition
rules
and
organization
of
melanin
and
appropriate
extraction
to
provide
the
reference.
Research
results
may
reveal
commonly
"color"
properties
of
molecular
genetic
mechanism,
and
chicken
and
research
and
development
of
the
ideal
bird
genetic
pattern,
expounds
the
animal
body
melanin
deposition
mechanism
for
research
of
"color"
commonly
character
and
the
birds
melanin
formation
mechanism
has
important
significance.