Characteristics of pulmonary microvascular structure in postnatal yaks.

Yaks are typical plateau-adapted animals, however the microvascular changes and characteristics in their lungs after birth are still unclear. Pulmonary microvasculature characteristics and changes across age groups were analysed using morphological observation and molecular biology detection in yaks aged 1, 30 and 180 days old in addition to adults. Results: Our experiments demonstrated that yaks have fully developed pulmonary alveolar at birth but that interalveolar thickness increased with age.

Degradation and DBP formations from pyrimidines and purines bases during sequential or simultaneous use of UV and chlorine.

Purine and pyrimidines are present an important pool of dissolved organic nitrogen in aqueous medias and also precursors of disinfection byproducts. The degradation kinetics of cytosine and adenine-model pyrimidine and purine compounds-were investigated along with their transformation pathways leading to the formation of disinfection byproducts during two typical multi-barrier disinfection processes: UV irradiation and UV/chlorine pretreatment followed by post-chlorination. UV irradiation followed by post-chlorination enhanced the degradation of cytosine and adenine (by 17.

Chlorite formation during ClO oxidation of model compounds having various functional groups and humic substances.

Chlorine dioxide (ClO) has been used as an alternative to chlorine in water purification to reduce the formation of halogenated by-products and give superior inactivation of microorganisms. However, the formation of chlorite (ClO) is a major consideration in the application of ClO. In order to improve understanding in ClO formation kinetics and mechanisms, this study investigated the reactions of ClO with 30 model compounds, 10 humic substances and 2 surface waters.