Limiting grazing periods combined with proper housing can reduce nutrient losses from dairy systems.

Pasture-based and grass-fed branding are often associated with consumer perceptions of improved human health, environmental performance and animal welfare. Here, to examine the impacts of dairy production in detail, we contrasted global observational (n = 156) data for nitrogen and phosphorus losses from land by the duration of outdoor livestock grazing in confined, grazed and hybrid systems. Observational nitrogen losses for confined systems were lowest on a productivity-but not area-basis.

Maximizing noble metal utilization in solid catalysts by control of nanoparticle location.

Maximizing the utilization of noble metals is crucial for applications such as catalysis. We found that the minimum loading of platinum for optimal performance in the hydroconversion of -alkanes for industrially relevant bifunctional catalysts could be reduced by a factor of 10 or more through the rational arranging of functional sites at the nanoscale. Intentionally depositing traces of platinum nanoparticles on the alumina binder or the outer surface of zeolite crystals, instead of inside the zeolite crystals, enhanced isomer selectivity without compromising activity.

Control and Impact of Metal Loading Heterogeneities at the Nanoscale on the Performance of Pt/Zeolite Y Catalysts for Alkane Hydroconversion.

The preparation of zeolite-based bifunctional catalysts with low noble metal loadings while maintaining optimal performance has been studied. We have deposited 0.03 to 1.

Influence of Nanoscale Intimacy and Zeolite Micropore Size on the Performance of Bifunctional Catalysts for -Heptane Hydroisomerization.

In this study, Pt nanoparticles on zeolite/γ-AlO composites (50/50 wt) were located either the zeolite or the γ-AlO binder, hereby varying the average distance (intimacy) between zeolite acid sites and metal sites from "closest" to "nanoscale". The catalytic performance of these catalysts was compared to physical mixtures of zeolite and Pt/γ-AlO powders, which provide a "microscale" distance between sites. Several beneficial effects on catalytic activity and selectivity for -heptane hydroisomerization were observed when Pt nanoparticles are located on the γ-AlO binder in nanoscale proximity with zeolite acid sites, as opposed to Pt nanoparticles located inside zeolite crystals.

Assessment of the Location of Pt Nanoparticles in Pt/zeolite Y/γ-AlO Composite Catalysts.

The location of Pt nanoparticles was studied in Pt/zeolite Y/γ-AlO composite catalysts prepared by HPtCl ⋅ 6HO (CPA) or Pt(NH)(NO) (PTA) as Pt precursors. The aim of this study is to validate findings from Transmission Electron Microscopy (TEM) by using characterization techniques that sample larger amounts of catalyst per measurement. Quantitative X-ray Photoelectron Spectroscopy (XPS) showed that the catalyst prepared with CPA led to a significantly higher Pt/Al atomic ratio than the catalyst prepared with PTA confirming that the 1-2 nm sized Pt nanoparticles in the former catalyst were located on the open and mesoporous γ-AlO component, whereas they were located in the micropores of zeolite Y in the latter.