Top IPC subclasses
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1
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F03D
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47
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Wind motors
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|
2
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C25B
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21
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Electrolytic or electrophoretic processes for the production of compounds or non- metals; apparatus therefor
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|
3
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F24J
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20
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Production or use of heat not otherwise provided for
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4
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H02M
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15
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apparatus for conversion between ac and ac, between ac and dc, or between dc and dc, and for use wit
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5
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G09B
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14
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educational or demonstration appliancesappliances for teaching, or communicating with, the blind, de
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6
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H02J
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13
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circuit arrangements or systems for supplying or distributing electric powersystems for storing elec
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7
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A01G
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12
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Horticulture; cultivation of vegetables, flowers, rice, fruit, vines, hops, or seaweed; forestry; watering
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|
8
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H05B
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9
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electric heatingelectric lighting not otherwise provided for
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9
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H01F
|
9
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magnetsinductancestransformersselection of materials for their magnetic properties
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|
10
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F24S
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9
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|
|
11
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C02F
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8
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Treatment of water, waste water, sewage, or sludge
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|
12
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H01L
|
7
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Semiconductor devices; electric solid state devices not otherwise provided for
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|
13
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F23D
|
6
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burners
|
|
14
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B01D
|
4
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Separation
|
|
15
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E02D
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4
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foundationsexcavationsembankmentsunderground or underwater structures
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|
16
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C25C
|
4
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processes for the electrolytic production, recovery or refining of metalsapparatus therefor
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|
17
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H01M
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4
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processes or means, e.g. batteries, for the direct conversion of chemical energy into electrical ene
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|
18
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F24H
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3
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fluid heaters, e.g. water or air heaters, having heat-generating means, in general
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|
19
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G01N
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3
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Investigating or analysing materials by determining their chemical or physical properties
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|
20
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B04B
|
2
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centrifuges
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