Pneumatic separator gives quick release to heavy loads

Pneumatic separator, using applied pressure, quickly releases restraining devices securing heavy loads. With minor modifications this separator can be used as a coupling device

Hypersonic test facility Patent

Hypersonic test facility for studying ablation in models under high pressure and high temperatur

WFPC2 LRF Imaging of Emission Line Nebulae in 3CR Radio Galaxies

We present HST/WFPC2 Linear Ramp Filter images of high surface brightness emission lines (either [OII], [OIII], or H-alpha+[NII]) in 80 3CR radio sources. We overlay the emission line images on high resolution VLA radio images (eight of which are new reductions of archival data) in order to examine the spatial relationship between the optical and radio emission. We confirm that the radio and optical emission line structures are consistent with weak alignment at low redshift (z < 0.6) except in the Compact Steep Spectrum (CSS) radio galaxies where both the radio source and the emission line nebulae are on galactic scales and strong alignment is seen at all redshifts. There are weak trends for the aligned emission line nebulae to be more luminous, and for the emission line nebula size to increase with redshift and/or radio power. The combination of these results suggests that there is a limited but real capacity for the radio source to influence the properties of the emission line nebulae at these low redshifts (z < 0.6). Our results are consistent with previous suggestions that both mechanical and radiant energy are responsible for generating alignment between the radio source and emission line gas.Comment: 80 pages, 54 figures. Accepted for publication in ApJ

Investigation on the structural behaviour of timber concrete composite connections

A project exploring innovative structural systems that utilise timber and provide a competitive alternative to steel and concrete products commenced at the University of Technology, Sydney, in 2007. It aims to identify and develop at least three flooring/framing concepts suitable for initial application in a two-/three-storey commercial building in Australia. In this context, a timber concrete composite (TCC) represents a competitive solution. An important aspect of TCC structures corresponds to the shear connectors, which are essential for TCC structural behaviour. Thus, they need to provide sufficient strength and impair slip between TCC layers. A laboratory investigation on these connectors is discussed in this paper. The scope and research plan are presented and the connection strength and stiffness are analysed and commented. © 2009 Taylor & Francis Group, London

Estimation of Juvenile Striped Bass Relative Abundance in the Virginia Portion of Chesapeake Bay Annual Progress Report: 2021 - 2022

The 2021 juvenile Striped Bass abundance index was 6.30 and was not significantly different than the reference mean of 7.77 for the period 1980 to 2009. Abundance indices were average in the York and Rappahannock rivers and below average in the James River in 2021 compared with the river‐specific reference means (1980‐2009). Relatively low catches of young‐of‐the‐year Striped Bass from sites upriver and downriver of core nursery areas suggest juvenile Striped Bass largely remained within core nursery areas in 2021. Juvenile abundance indices for Alewife, American Shad, Atlantic Croaker, Atlantic Silverside, and Spot were generally below their historic averages in 2021. In contrast, abundance indices for Banded Killifish, and Spottail Shiner in 2021 were generally greater than their historic averages in Virginia waters. Inland Silverside abundance in 2021 was similar to the historic average observed in Virginia waters. Juvenile White Perch abundance indices in 2021 were above historic averages in the York and Rappahannock river systems, but below historic averages in the James River. The juvenile abundance index for Blueback Herring was average in all rivers, except the Pamunkey River, where below‐average recruitment was observed. Together, these results suggest modest production of forage fish prey for piscivores in Virginia

Estimation of Juvenile Striped Bass Relative Abundance in the Virginia Portion of Chesapeake Bay Annual Progress Report: 2023 - 2024

The 2023 juvenile Striped Bass abundance index was 4.26 and was significantly lower than the reference mean of 7.77 for the period 1980 to 2009. Abundance indices were below average in the James and Rappahannock rivers and average in the York River in 2023 compared with the river-specific reference means (1980-2009). Relatively low catches of young‐of‐the‐year Striped Bass from sites upriver and downriver of core nursery areas suggest juvenile Striped Bass largely remained within core nursery areas in 2023. Indices of abundance were calculated for three additional economically and recreationally important fishes in Virginia waters. Juvenile White Perch abundance indices in 2023 were below historic averages in the James, York, and Rappahannock river systems. Atlantic Croaker abundance in 2023 was greater than the historic average observed in Virginia waters. In contrast, the abundance index for Spot in 2023 was generally below the historic average in Virginia waters. Indices of abundance were calculated for seven common forage species within the tidal nearshore zone of Virginia waters. In 2023, the abundance index was also calculated for another common forage species in Virginia waters, Mummichog (Fundulus heteroclitus). Abundance indices for Atlantic Silverside and Mummichog were generally below their historic averages in 2023. The abundance indices for Banded Killifish, Inland Silverside, and Spottail Shiner were generally similar to their historic averages in 2023. For the second consecutive year, a record high abundance index was recorded for American Shad in the Rappahannock River. The abundance index for American Shad was average in the Mattaponi and Pamunkey rivers, and below average in the James, Chickahominy, and York rivers. The abundance indices for Alewife were below average in the James and York rivers, but average in the Rappahannock River. Abundance indices for Blueback Herring were average in the James and York rivers, but below average in the Rappahannock River. Together, these results suggest modest production of forage fish prey for piscivores in Virginia

Estimation of Juvenile Striped Bass Relative Abundance in the Virginia Portion of Chesapeake Bay Annual Progress Report: 2022 - 2023

The 2022 juvenile Striped Bass abundance index was 7.95 and was not significantly different than the reference mean of 7.77 for the period 1980 to 2009. Abundance indices were average in the York and Rappahannock rivers and below average in the James River in 2022 compared with the river-specific reference means (1980-2009). Relatively low catches of young‐of‐the‐year Striped Bass from sites upriver and downriver of core nursery areas suggest juvenile Striped Bass largely remained within core nursery areas in 2022. Indices of abundance were also calculated for three additional economically and recreationally important fishes in Virginia waters. Juvenile White Perch abundance indices in 2022 were above historic averages in the York and Rappahannock river systems, but similar to the historic average in the James River. Atlantic Croaker abundance in 2022 was similar to the historic average observed in Virginia waters. In contrast, the abundance index for Spot in 2022 was generally below the historic average in Virginia waters

The heating mechanism for the warm/cool dust in powerful, radio-loud AGN

The uncertainty surrounding the nature of the heating mechanism for the dust that emits at mid- to far-IR (MFIR) wavelengths in active galaxies limits our understanding of the links between active galactic nuclei (AGN) and galaxy evolution, as well as our ability to interpret the prodigious infrared and sub-mm emission of some of the most distant galaxies in the Universe. Here we report deep Spitzer observations of a complete sample of powerful, intermediate redshift (0.05 < z < 0.7) radio galaxies and quasars. We show that AGN power, as traced by [OIII]5007 emission, is strongly correlated with both the mid-IR (24 micron) and the far-IR (70 micron) luminosities, however, with increased scatter in the 70 micron correlation. A major cause of this increased scatter is a group of objects that falls above the main correlation and displays evidence for prodigious recent star formation activity at optical wavelengths, along with relatively cool MFIR colours. These results provide evidence that illumination by the AGN is the primary heating mechanism for the dust emitting at both 24 and 70 microns, with starbursts dominating the heating of the cool dust in only 20 -- 30% of objects. This implies that powerful AGN are not always accompanied by the type of luminous starbursts that are characteristic of the peak of activity in major gas-rich mergers.Comment: 13 pages, 3 figures. Accepted for publication in astrophysical journal letter