Microwave Oven

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Microwave Oven
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Relationship between microwave oven and Science

• Relative to Physics microwave oven mainly use
  microwave to work.
• Relative to Chemistry microwave oven use
  electricity power to work.
• Relative to Biology microwave oven kill
  enzymes when using.

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Microwaves

• Microwave,that is one kind of a wavelength which
  is an very short electromagnetic wave,that
  wavelength can only have few millimeter.Although,m
  icrowaves wavelength is very short, its energy
  doesn't small.If use special way to put the
  beams energy to flock together,it can facing
  human being or weaponry to bring threaten.This is
  famous microwaves weapons,which is one of
  directional weapons.

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History of microwave

• The develop of microwave cant separate with the
  develop wireless communication.In 1901,Lyman
  Harry use 800KHz of a medium wave signal out from
  England to North America Newfoundland.Is the
  first time to traverse the Atlantic Ocean of the
  test of communication test.To initiate humanity
  wireless communication an epoch.The initial stage
  of wireless communication,people use long wave
  and medium wave for communication.The early
  20century 20ages,people discovered short
  communication,up to 20century 60ages satellite
  communication spring,it all along is the main
  method of international long range
  communication.As well as facing to meet an
  emergency and military communication still very
  important just now.

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Microwave application summary

• In fact,microwave is nearby us,such as common
  consumers terminology microwave is to signify
  using microwave oven,many families use it to
  heating food.
• Industry and medicine application also using
  microwave for heating. Microwave oven is a quite
  simple system,make by high power
  fountainhead,waveguide wire and stove.

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Microwave communication

• Microwave is a kind of frequency which is
  extremely high (normally about 300MHz to 300GHz)
  ,wavelength is very short,usually about 1mm to 1m
  of electromagnetic wave.In microwave
  frequency,owing to frequency is very high
  ,electric waves diffraction power is low, signal
  transmission mainly use to microwaves in line of
  vision distance rectilinear propagation. This
  type of transmission method ,though compare with
  short wave,to be provided with transmission is
  more stable,only have little external
  interference advantages etc. But in the
  transmission of electric wave,is hard to avoid
  reflection,refraction,scattering or absorption,
  by landforms,buildings and weather effects, to
  result transmission decline and transmission not
  real.

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Energy supply of microwave oven
Microwave oven is use electricity to work.In Hong
Kong,the energy source of people use,mainly
produced by petroleum products,the next is coal
and natural gas. The total generate power
capacity of Hong Kong, include Guangdong Nuclear
Power Plant 70 of the generate power capacity,as
well as 50 of generate power capacity of the
Guangdong pumped storage. The ratio of Hong Kong
generating electricity power of fuel materials
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Coal
Name Coal Type Solid , rock ,
minerals Location Inside the earth crust
stratum Life Long , but not renewable The main
components of coal is carbon,hydrogen,oxygen and
small amount of nitrogen,sulphur and other
elements. In ancient times,large amount of plants
were flushed under the ground after dead,range
upon range of,over long years and the variation
of the earth crust. During different temperature
and pressure, gradually charcoal change to
various coal seam. At present,the reserves of
coal,estimate can use more 200years.Concrete
circumstance,affected by these causediscover of
reserves of new coalfield,speed of
production,speed of consumption,speed of using
other energy source etc.
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The constitution of enzyme
The constitution of enzyme
Enzymes are proteins. They are composed of amino
acids. Enzymes are catalysts to accelerate all
chemical reactions in the body. Each reaction
requires a specific enzyme. Enzymes substrates
are accepted by enzymes to give products. Enzyme
inhibitors are molecules to stop reactions. A
type of protein that catalyses biological
reactions. Enzymes have to operate in certain
environment conditions (such as a thirty seven
degree Celsius temperature in humans) to operate
optimally.There can be factors, like a change
in temperature or the absence of a coenzyme that
will reduce the effectiveness of an enzymes'
reaction. Any of several complex proteins that
are produced by cells and act as catalysts in
specific biochemical reactions.
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