A linear knife grid device was developed for first-stage size reduction of high- and low-moisture switchgrass (Panicum virgatum L.), a tough, fibrous perennial grass being considered as a feedstock for bioenergy. The size reduction is by a shearing action accomplished by forcing a thick packed bed of biomass against a grid of sharp knives. The system is used commercially for slicing forages for...

Arsenic released by bottom sediments was determined by experiments in which the sediments were artificially re-suspended using a particle entrainment simulator (PES) to simulate river conditions. Sediment cores were collected from various tributaries to drinking water reservoirs in Connecticut spiked with arsenic, and run in the PES at simulated bed-flow shear stresses from 0.0 to 0.6 N/m(2). U...

Using simple theoretical models and field measurements from a springdominated stream, we quantify how large woody debris affect channel hydraulics and morphology at both the local and reach-averaged scales. Because spring-dominated streams have nearly constant discharge, they provide a unique natural opportunity to study flow and transport processes near the channel-forming flow. We first show ...

hydrodynamics and sediment transport model used to determine the longand short-term stability of dredged material mounds. This technical note (TN) introduces a new cohesive sediment transport submodel for LTFATE, which includes a combined current-wave shear stress calculation and a layered sediment bed model. LTFATE can be accessed via the Internet at the following address: http://www.wes.army....