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Updated: Jul 2, 2026
07:33
Quantifying Mixing using Magnetic Resonance Imaging
Published on: January 25, 2012
Magnetic stirrer with no external moving parts
1Department of Chemistry, Rice University, Houston, TX 77001, USA.
The Review of Scientific Instruments
|October 1, 1978
Summary
A novel electronic system generates a rotating magnetic field for a variable speed stirrer. This technology enables precise control over stirring speed using digital circuitry and magnetic coils.
Area of Science:
- Electronics
- Mechanical Engineering
- Laboratory Equipment
Background:
- Traditional stirrers often lack precise speed control.
- Electronic control of magnetic fields offers potential for improved stirring.
- Developing a variable speed stirrer is crucial for various scientific applications.
Purpose of the Study:
- To describe a novel variable speed stirrer.
- To detail the electronic control mechanism for a rotating magnetic field.
- To present a digital approach for generating precise stirring speeds.
Main Methods:
- Utilized digital circuitry to generate two 90-degree phase-shifted stepped functions approximating sine waves.
- Amplified these signals to drive perpendicular coils.
- Employed a rotating magnetic field to control stirrer speed.
Main Results:
- Successfully created a variable speed stirrer based on electronic magnetic field rotation.
- Demonstrated precise speed control through digital signal generation.
- The system effectively rotates a magnet at a chosen speed.
Conclusions:
- The described electronic system provides a reliable method for variable speed stirring.
- Digital control offers an efficient and accurate approach to magnetic stirrer operation.
- This technology has potential applications in laboratory settings requiring controlled mixing.
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