University of Windsor

About: University of Windsor is a education organization based out in Windsor, Ontario, Canada. It is known for research contribution in the topics: Population & Argumentation theory. The organization has 10654 authors who have published 22307 publications receiving 435906 citations. The organization is also known as: UWindsor & Assumption University of Windsor.

Relationships between denitrification, microbial biomass and indigenous soil properties

Abstract: The relationships between denitrification, soil microbial biomass and selected soil properties were investigated in 13 soils which varied in physical and chemical properties. It was hypothesized that estimates of biomass C may be directly related to the background (unamended) denitrification rates. Denitrification potential (with C and NO−3 amendments) was also compared to biomass C and the indigenous soil properties. The background and potential denitrification rates were measured in these soils during 75 h of anacrobiosis. Background denitrification was highly correlated with biomass C. organic C content and moisture content at field capacity (−33 kPa). Soil organic C was also highly correlated with microbial biomass C. Nitrate was not limiting for most soils as in all but two soils the residual NO−3 content following incubation exceeded 10mg N kg−1. Hence. NO−3 concentration was not strongly correlated with the background denitrification rate. The denitrification potential was 5 times greater than background denitrification. In our study, C was the factor limiting denitrification. Further, microbial biomass appeared to be a sensitive indicator of both soil C content and background denitrification. There was no significant relationship between any of the other soil chemical and physical properties measured and the denitrification potential.

Surface Evolution of PtCu Alloy Shell over Pd Nanocrystals Leads to Superior Hydrogen Evolution and Oxygen Reduction Reactions

Abstract: Pt-based electrocatalysts are by far the most effective for the hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR), but they still suffer from high cost and insufficient overall performance. Improving Pt utilization via alloying or by forming core@shell structures is important for enhancing Pt activity and overall electrocatalytic performance. Herein, we report a simple seed-mediated method for synthesizing a dodecahedral PtCu alloy atomic shell on Pd nanocrystals. Significantly, such a Pd@PtCu nanocomposite with unique core@alloy-shell structure achieves a 25-fold and 6-fold enhancement of mass activity for HER and ORR, respectively, compared with the commercial Pt/C catalyst in acid media. Moreover, the unique Pd@PtCu catalyst shows only 1.0 mV increase in overpotential at 10 mA cm–2 after 10 000 cycles for HER and almost no activity decay after 5 000 cycles for ORR, indicating the high endurance of Pd@PtCu in the electrochemical environment.