An all-electrical torque differential magnetometer operating under ambient conditions

An all-electrical torque differential magnetometry (also known as cantilever magnetometry) setup employing piezoelectric quartz tuning forks is demonstrated. The magnetometer can be operated under ambient conditions as well as low temperatures and pressures. It extends the allowed specimen mass range up to several 10 $\mu$g without any significant reduction in the sensitivity. Operation under ambient conditions and a simple all-electrical design of the magnetometer should allow for an easy integration with other experimental setups. The uniaxial magnetic anisotropy of a 25 $\mu$m diameter iron wire, measured under ambient conditions with a high signal to noise ratio, was found to be in good agreement with its literature value. Further applications of the technique are discussed.Comment: 9 two-column pages, 9 figure

ENVILAB: Measuring phytoplankton in-vivo absorption and scattering properties under tunable environmental conditions

Optical remote sensing of phytoplankton draws on distinctive spectral features which can vary with both species and environmental conditions. Here, we present a set-up (ENVILAB) for growing phytoplankton under well-defined light, temperature and nutrient conditions. The custom-built light source enables creation of light with spectral composition similar to natural aquatic environments. Spectral tuning allows for light quality studies. Attenuation is monitored with a spectrometer in transmission mode. In combination with automated spectrophotometer and fluorimeter measurements, absorption and excitationemission-fluorescence spectra are recorded. The set-up opens the door for systematic studies on phytoplankton optical properties and physiology