A new methodology for the quantitative visualization of coherent flow structures in alluvial channels using multibeam echo-sounding (MBES)

In order to investigate the interactions between turbulence and suspended sediment transport in natural aqueous environments, we ideally require a technique that allows simultaneous measurement of fluid velocity and sediment concentration for the whole flow field. Here, we report on development of a methodology using the water column acoustic backscatter signal from a multibeam echo sounder to simultaneously quantify flow velocities and sediment concentrations. The application of this new technique is illustrated with reference to flow over the leeside of an alluvial sand dune, which allows, for the first time in a field study, quantitative visualization of large-scale, whole flow field, turbulent coherent flow structures associated with the dune leeside that are responsible for suspending bed sediment. This methodology holds great potential for use in a wide range of aqueous geophysical flows

Primitive Early Eocene bat from Wyoming and the evolution of flight and echolocation

Bats ( Chiroptera) represent one of the largest and most diverse radiations of mammals, accounting for one- fifth of extant species(1). Although recent studies unambiguously support bat monophyly(2-4) and consensus is rapidly emerging about evolutionary relationships among extant lineages(5-8), the fossil record of bats extends over 50 million years, and early evolution of the group remains poorly understood(5,7-9). Here we describe a new bat from the Early Eocene Green River Formation of Wyoming, USA, with features that are more primitive than seen in any previously known bat. The evolutionary pathways that led to flapping flight and echolocation in bats have been in dispute(7-18), and until now fossils have been of limited use in documenting transitions involved in this marked change in lifestyle. Phylogenetically informed comparisons of the new taxon with other bats and non- flying mammals reveal that critical morphological and functional changes evolved incrementally. Forelimb anatomy indicates that the new bat was capable of powered flight like other Eocene bats, but ear morphology suggests that it lacked their echolocation abilities, supporting a 'flight first' hypothesis for chiropteran evolution. The shape of the wings suggests that an undulating gliding - fluttering flight style may be primitive for bats, and the presence of a long calcar indicates that a broad tail membrane evolved early in Chiroptera, probably functioning as an additional airfoil rather than as a prey-capture device. Limb proportions and retention of claws on all digits indicate that the new bat may have been an agile climber that employed quadrupedal locomotion and under- branch hanging behaviour.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/62816/1/nature06549.pd

Predictive Engineering Tools for Injection-Molded Long-Carbon-Fiber Thermoplastic Composites - FY13 Third Quarterly Report

This quarterly report summarizes the status for the project planning to obtain all the approvals required for a Cooperative Research and Development Agreement (CRADA) with Autodesk, Inc., Toyota Motor Engineering and Manufacturing North America (Toyota), and Magna Exterior and Interiors Corporation (Magna). The CRADA documents have been processed by PNNL Legal Services that is also coordinating the revision effort with the industrial parties to address DOE’s comments

Predictive Engineering Tools for Injection-Molded Long-Carbon-Fiber Thermoplastic Composites - FY13 Fourth Quarterly Report

This quarterly report summarizes the status for the project planning to complete all the legal and contract documents required for establishing the subcontracts needed and a Cooperative Research and Development Agreement (CRADA) with Autodesk, Inc., Toyota Motor Engineering and Manufacturing North America (Toyota), and Magna Exterior and Interiors Corporation (Magna). During the second quarter (1/1/2013 to 3/31/2013), all the technical and legal documents for the subcontracts to Purdue University, University of Illinois, and PlastiComp, Inc. were completed. The revised CRADA documents were sent to DOE, Autodesk, Toyota, and Magna for technical and legal reviews. PNNL Legal Services contacted project partners’ Legal counterparts for completing legal documents for the project. A non-disclosure agreement was revised and sent to all the parties for reviews

Characterization of Sound Transmission Loss of Laminated Glass with Analytical and Experimental Approaches

In this project, we have developed the general formation for calculating transmission loss of sound waves through multi-layered structures. Full factorial design method has also been used to investigate the relative effect of various geometric and material parameters on the transmission loss. It was found that within the range of practical interest, the most effect way of increasing transmission loss is by increasing either the glass thickness or increasing the inner layer mass density. Experimental measurements of sound transmission loss (in decibels) for four laminated glass samples have been made in accordance to SAE J1400, in third-octave bands between 125 Hz and 8 kHz

Polymers for hydrogen infrastructure and vehicle fuel systems : applications, properties, and gap analysis.

This document addresses polymer materials for use in hydrogen service. Section 1 summarizes the applications of polymers in hydrogen infrastructure and vehicle fuel systems and identifies polymers used in these applications. Section 2 reviews the properties of polymer materials exposed to hydrogen and/or high-pressure environments, using information obtained from published, peer-reviewed literature. The effect of high pressure on physical and mechanical properties of polymers is emphasized in this section along with a summary of hydrogen transport through polymers. Section 3 identifies areas in which fuller characterization is needed in order to assess material suitability for hydrogen service