| 摘要 |
A heatable pipette, with a needle has an inner channel defined by an inner wall, arranged to conduct electric current through the inner wall for resistively heating the inner wall. The needle has an outer wall, which is defined between the outer wall and the inner wall and connectable for providing pressure air into the outer channel. By conducting current directly through the inner wall, the inner wall itself operates as resistor. Particularly, if the inner wall is made of an appropriate material, for example of stainless steel, the ohmic resistance of the inner wall is not negligible even if the inner wall is very thin. Therefore, the inner wall can directly be used as resistor for resistance heating of the inner wall even if the needle is manufactured in small dimensions.
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