Observation of snake resonances at Relativistic Heavy Ion Collider (open access)

Observation of snake resonances at Relativistic Heavy Ion Collider

The Siberian snakes are powerful tools in preserving polarization in high energy accelerators has been demonstrated at the Brookhaven Relativistic Heavy Ion Collider (RHIC). Equipped with two full Siberian snakes in each ring, polarization is preserved during acceleration from injection to 100 GeV. However, the Siberian snakes also introduce a new set of depolarization resonances, i.e. snake resonances as first discovered by Lee and Tepikian. The intrinsic spin resonances above 100 GeV are about a factor of two stronger than those below 100 GeV which raises the challenge to preserve the polarization up to 250 GeV. In 2009, polarized protons collided for the first time at the RHIC design store energy of 250 GeV. This paper presents the experimental measurements of snake resonances at RHIC. The plan for avoiding these resonances is also presented.
Date: September 27, 2010
Creator: Bai, M.; Ahrens, L.; Alekseev, I.G.; Alessi, J. & al, et
System: The UNT Digital Library
PRESERVATION OF H2 PRODUCTION ACTIVITY IN NANOPOROUS LATEX COATINGS OF RHODOPSEUDOMONAS PALUSTRIS CGA009 DURING DRY STORAGE AT AMBIENT TEMPERATURES (open access)

PRESERVATION OF H2 PRODUCTION ACTIVITY IN NANOPOROUS LATEX COATINGS OF RHODOPSEUDOMONAS PALUSTRIS CGA009 DURING DRY STORAGE AT AMBIENT TEMPERATURES

To assess the applicability of latex cell coatings as an "off-the-shelf' biocatalyst, the effect of osmoprotectants, temperature, humidity and O{sub 2} on preservation of H{sub 2} production in Rhodopseudomonas palustris coatings was evaluated. Immediately following latex coating coalescence (24 h) and for up to 2 weeks of dry storage, rehydrated coatings containing different osmoprotectants displayed similar rates of H{sub 2} production. Beyond 2 weeks of storage, sorbitol- treated coatings lost all H{sub 2} production activity, whereas considerable H{sub 2} production was still detected in sucrose- and trehalose-stabilized coatings. The relative humidity level at which the coatings were stored had a significant impact on the recovery and subsequent rates of H{sub 2} production. After 4 weeks storage under air at 60% humidity, coatings produced only trace amounts of H{sub 2} (0-0.1% headspace accumulation), whereas those stored at <5% humidity retained 27-53% of their H{sub 2} production activity after 8 weeks of storage. When stored in argon at <5% humidity and room temperature, R. palustris coatings retained full H{sub 2} production activity for 3 months, implicating oxidative damage as a key factor limiting coating storage. Overall, the results demonstrate that biocatalytic latex coatings are an attractive cell immobilization platform for preservation of …
Date: August 27, 2012
Creator: Milliken, C.; Piskorska, M.; Soule, T.; Gosse, J.; Flickinger, M.; Smith, G. et al.
System: The UNT Digital Library
Self-efficacy mechanism at work: The context of environmental volunteer travel (open access)

Self-efficacy mechanism at work: The context of environmental volunteer travel

This article contributes the first utilization of Bandura’s self-efficacy (SE) mechanism in the context of environmental volunteer travel demonstrating how environmental stewardship, hedonic experience, and environmental SE relate to one another in this particular setting
Date: December 27, 2018
Creator: Strzelecka, Marianna; Woosnam, Kyle M. & Nisbett, Gwendelyn S.
System: The UNT Digital Library
Chemistry of Supraglacial Ponds in thte Debris-Covered Area of Lirung Glacier in Central Nepal Himalayas (open access)

Chemistry of Supraglacial Ponds in thte Debris-Covered Area of Lirung Glacier in Central Nepal Himalayas

This article examines elevation trends and their control by seasonality, dominant geochemical processes, and season dynamics in these supraglacial ponds at elevations ranging between 3989 and 4292 m above sea level in the debris-covered area of Lirung glacier in central Nepal Himalayas, from November 2010 to October 2011 on a bimonthly basis.
Date: August 27, 2015
Creator: Bhatt, Maya P.; Takeuchi, Nozomu & Acevedo, Miguel F.
System: The UNT Digital Library