Bis(2-phenyl-4,6-di-2-pyridyl-1,3,5-triazine-κ3 N 4,N 5,N 6)ruthenium(II) bis(hexa­fluoridophosphate)

The asymmetric unit of the title compound, [Ru(C19H13N5)2](PF6)2, consists of an RuII complex cation and two hexa­fluoridophosphate anions. The RuII atom is coordinated by three N atoms from the two outer pyridine and the central triazine rings of each of two tridentate ligands in a distorted octa­hedral environment. The ligands are approximately orthogonal to one another, with a dihedral angle of 88.34 (2)° between planes through the three six-membered rings of the two ligands. The pendant phenyl substituents are almost coplanar with the triazine rings to which they are bound, with dihedral angles of 5.41 (9) and 14.90 (10)°. This is reflected in the previously reported photophysical results with an increased lifetime of the triplet metal to ligand charge transfer (3MLCT) excited state [Fang, Taylor, Hanan, Loiseau, Passalacqua, Campagna, Nierengarten & Van Dorsselaer (2002). J. Am. Chem. Soc. 124, 7912–7913]

Lab Investigation of Nitrogen Application Timing, Nitrogen Source, and NZoneMax Addition on Nitrate Leaching

Proper manure and nutrient management is essential to ensure maximum crop production while reducing the risk of N losses. There is concern, that fall application of liquid swine manure can lead to economic and environmental concerns due to potential for losses of nitrate. Thus, the objective of this study was to evaluate the impact of application timing (fall vs. spring) and use of NZoneMax applied with liquid swine manure (LSM) or urea had on nitrogen loss. The study was conducted as a laboratory soil incubation over 35-days with leaching performed on days 3, 7, 10, 14, 21, 28, and 35. Treatments included a control soil receiving no nitrogen application and treatments of LSM or urea fertilizer applied at a rate of 168 kg N/ha (150 lb N/acre) applied with and without NZoneMax, tested on two different Iowa soils, and simulating a spring and fall application. In the spring application soil incubations began immediately after fertilizer application occurred, for the fall applications fertilizer sources were added soils were placed in a freezer for 3 months and then brought to room temperature where they were incubated for 35 days. Results indicated that application timing, nitrogen source, additive, and the application timing x nitrogen source factors were all significant with less nitrogen leaching occurring from the spring application, the manure as compared to the urea, and fertilizers receiving the NZoneMax treatment. In general, NZoneMax reduced nitrate leaching by 13% over the incubation while spring versus fall application reduced leaching by about 35%. Manure initially leached nitrogen more slowly than urea; however, by day 28 of the incubation the difference was no longer statistically significant. These results provide insight into how different fertilization choices may impact nitrogen loss

Diffuse flow environments within basalt- and sediment-based hydrothermal vent ecosystems harbor specialized microbial communities

Hydrothermal vents differ both in surface input and subsurface geochemistry. The effects of these differences on their microbial communities are not clear. Here, we investigated both alpha and beta diversity of diffuse flow-associated microbial communities emanating from vents at a basalt-based hydrothermal system along the East Pacific Rise (EPR) and a sediment-based hydrothermal system, Guaymas Basin. Both Bacteria and Archaea were targeted using high throughput 16S rRNA gene pyrosequencing analyses. A unique aspect of this study was the use of a universal set of 16S rRNA gene primers to characterize total and diffuse flow-specific microbial communities from varied deep-sea hydrothermal environments. Both surrounding seawater and diffuse flow water samples contained large numbers of Marine Group I (MGI) Thaumarchaea and Gammaproteobacteria taxa previously observed in deep-sea systems. However, these taxa were geographically distinct and segregated according to type of spreading center. Diffuse flow microbial community profiles were highly differentiated. In particular, EPR dominant diffuse flow taxa were most closely associated with chemolithoautotrophs, and off axis water was dominated by heterotrophic-related taxa, whereas the opposite was true for Guaymas Basin. The diversity and richness of diffuse flow-specific microbial communities were strongly correlated to the relative abundance of Epsilonproteobacteria, proximity to macrofauna, and hydrothermal system type. Archaeal diversity was higher than or equivalent to bacterial diversity in about one third of the samples. Most diffuse flow-specific communities were dominated by OTUs associated with Epsilonproteobacteria, but many of the Guaymas Basin diffuse flow samples were dominated by either OTUs within the Planctomycetes or hyperthermophilic Archaea. This study emphasizes the unique microbial communities associated with geochemically and geographically distinct hydrothermal diffuse flow environments

Integration Schemes for Dissipative Particle Dynamics Simulations: From Softly Interacting Systems Towards Hybrid Models

We examine the performance of various commonly used integration schemes in dissipative particle dynamics simulations. We consider this issue using three different model systems, which characterize a variety of different conditions often studied in simulations. Specifically we clarify the performance of integration schemes in hybrid models, which combine microscopic and meso-scale descriptions of different particles using both soft and hard interactions. We find that in all three model systems many commonly used integrators may give rise to surprisingly pronounced artifacts in physical observables such as the radial distribution function, the compressibility, and the tracer diffusion coefficient. The artifacts are found to be strongest in systems, where interparticle interactions are soft and predominated by random and dissipative forces, while in systems governed by conservative interactions the artifacts are weaker. Our results suggest that the quality of any integration scheme employed is crucial in all cases where the role of random and dissipative forces is important, including hybrid models where the solvent is described in terms of soft potentials

(η6-Benzene)(2,2′-bipyridine-κ2 N,N′)chloridoruthenium(II) chloride methanol sesquisolvate

In the title compound, [RuCl(C6H6)(C10H8N2)]Cl·1.5CH4O, the RuII atom is in a distorted octa­hedral environment coordinated by an η6-benzene ring, a chelating 2,2′-bipyridine ligand and a chloride ion. The asymmetric unit is completed by a chloride anion and two methanol mol­ecules, one of which is disordered about a centre of inversion with an occupancy of 0.5. It is an example of a ruthenium complex with a less sterically congested environment than in similar derivatives. In the crystal structure, O—H⋯Cl hydrogen bonds, together with π–π stacking inter­actions [centroid–centroid distances of 3.472Å(2) Å], stabilize the structure

A commentary on Xenophon's 'Àpologia Sokratous'

This thesis is a commentary on Xenophon the Athenian's (Apology of Socrates), a work written in the first half of the 4th century B.C. with the express purpose of explaining Socrates' self-aggrandizing behaviour during his trial in 399. The commentary is prefaced by three essays which treat the issues of authenticity, dating, and possible non-Platonic influences on the work, while the four appendices contain comparisons with Xenophon's Memorabilia and Plato's Apology as well as treatments of Socrates' daimonic sign and his arrogant behaviour during the trial as described by Xenophon. Based on the 1919 Oxford Classical Text edited by E. C. Marchant, the commentary itself is a line-by-line analysis concerned primarily with providing a social, historical, and literary context for each passage under consideration