Microclimate and ventilation in Estonian and Finnish dairy buildings

A series of ventilation, thermal and indoor air quality measurements were performed in 14 different dairy buildings in Estonia and Finland. The number of animals in the buildings varied from 30 to 600. Measurements were made all year round with ambient temperatures ranging between −40 °C and +30 °C. The results showed that microclimatic conditions in the dairy buildings were affected by the design of the building, outside temperature, wind, ventilation and manure handling method. The average inside air concentration of carbon dioxide was 950 ppm, ammonia 5 ppm, methane 48 ppm, relative humidity 70% and inside air velocity was 0.2 m/s. Although occasionally exceeded, the ventilation and average indoor air quality in the dairy buildings were mainly within the recommended limits.     

Femtosecond resonance enhanced CARS for background-free detection of organic molecules

We study the coherent excitation profile (CEP) of resonance enhanced femtosecond CARS in a model system zinc phthalocyanine in a polymer film host as a prospective technique for detection and identification of molecular species in ambient environments. A new method of suppressing the non-resonant FWM background is demonstrated. Transform theory is applied to calculate CEP based on the absorption spectrum, and good agreement between theory and experiment is obtained.