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Full-Text Articles in Physical Sciences and Mathematics
Projection Of Diffraction Patterns For Use In Cold-Neutral-Atom Trapping, Katharina Gillen-Christandl, Glen D. Gillen
Projection Of Diffraction Patterns For Use In Cold-Neutral-Atom Trapping, Katharina Gillen-Christandl, Glen D. Gillen
Glen Gillen
Scalar diffraction theory is combined with beam-propagation techniques to investigate the projection of near-field diffraction patterns to spatial locations away from the aperture for use in optically trapping cold neutral alkali-metal atoms. Calculations show that intensity distributions with localized bright and dark spots usually found within a millimeter of the diffracting aperture can be projected to a region free from optical components such as a cloud of cold atoms within a vacuum chamber. Calculations also predict that the critical properties of the optical dipole atom traps are not only maintained for the projected intensity patterns but also can be manipulated …
Projection Of Diffraction Patterns For Use In Cold-Neutral-Atom Trapping, Katharina Gillen-Christandl, Glen D. Gillen
Projection Of Diffraction Patterns For Use In Cold-Neutral-Atom Trapping, Katharina Gillen-Christandl, Glen D. Gillen
Katharina Gillen
Scalar diffraction theory is combined with beam-propagation techniques to investigate the projection of near-field diffraction patterns to spatial locations away from the aperture for use in optically trapping cold neutral alkali-metal atoms. Calculations show that intensity distributions with localized bright and dark spots usually found within a millimeter of the diffracting aperture can be projected to a region free from optical components such as a cloud of cold atoms within a vacuum chamber. Calculations also predict that the critical properties of the optical dipole atom traps are not only maintained for the projected intensity patterns but also can be manipulated …
Chemistry–Climate Model Simulations Of Twenty-First Century Stratospheric Climate And Circulation Changes, Neal Butchart, I. Cionni, V. Eyring, T. G. Shepherd, D. W. Waugh, H. Akiyoshi, J. Austin, C. Brühl, M. P. Chipperfield, Eugene C. Cordero, M. Dameris, R. Deckert, S. Dhomse, S. M. Frith, R. R. Garcia, A. Gettelman, M. A. Giorgetta, D. E. Kinnison, F. Li, E. Mancini, S. Pawson, G. Pitari, D. A. Plummer, E. Rozanov, F. Sassi, J. F. Scinocca, K. Shibata, B. Steil, W. Tian
Chemistry–Climate Model Simulations Of Twenty-First Century Stratospheric Climate And Circulation Changes, Neal Butchart, I. Cionni, V. Eyring, T. G. Shepherd, D. W. Waugh, H. Akiyoshi, J. Austin, C. Brühl, M. P. Chipperfield, Eugene C. Cordero, M. Dameris, R. Deckert, S. Dhomse, S. M. Frith, R. R. Garcia, A. Gettelman, M. A. Giorgetta, D. E. Kinnison, F. Li, E. Mancini, S. Pawson, G. Pitari, D. A. Plummer, E. Rozanov, F. Sassi, J. F. Scinocca, K. Shibata, B. Steil, W. Tian
Eugene C. Cordero
The response of stratospheric climate and circulation to increasing amounts of greenhouse gases (GHGs) and ozone recovery in the twenty-first century is analyzed in simulations of 11 chemistry–climate models using near-identical forcings and experimental setup. In addition to an overall global cooling of the stratosphere in the simulations (0.59 ± 0.07 K decade−1 at 10 hPa), ozone recovery causes a warming of the Southern Hemisphere polar lower stratosphere in summer with enhanced cooling above. The rate of warming correlates with the rate of ozone recovery projected by the models and, on average, changes from 0.8 to 0.48 K decade …
Essential Elements Of Sustainable Fire Management In The Wildland-Urban Interface, Christopher Dicus
Essential Elements Of Sustainable Fire Management In The Wildland-Urban Interface, Christopher Dicus
Christopher Dicus
Fire and fuels management in the wildland-urban interface is a multifaceted aggregation of biophysical and sociopolitical components. To best insure sustainable communities in the wildland-urban interface, stakeholders from a diversity of disciplines and worldviews must collaborate to develop a management plan for a given area that minimizes fire risk while simultaneously maximizing the benefits that distinct vegetation types and structures provide. This paper discusses critical elements that must be considered in order to maintain sustainable communities in the wildland-urban interface. These factors include fuels treatments, suppression forces, enforceable infrastructure and construction standards, and community education, each of which will vary …
Restoration Of Mixed Conifer Communities Using Prescribed Fire In Bryce Canyon National Park, Michael J. Jenkins, Christopher Dicus, Joel E. Godfrey
Restoration Of Mixed Conifer Communities Using Prescribed Fire In Bryce Canyon National Park, Michael J. Jenkins, Christopher Dicus, Joel E. Godfrey
Christopher Dicus
A fire history conducted in the mixed conifer community types of Bryce Canyon National Park found the mean fire-return interval has lengthened from 7.5 to 45 years since 1900. Dendroecology, species, diameter, and age-class analysis showed a change in stand composition in favor of white fir (Abies concolor) and Douglas-fir (Psuedotsuga menziesii) and a 200% increase in fuel accumulation. Recommendations for prescribed burning and mechanical reduction of fuels were incorporated into the Bryce Canyon management plan.
Making Space For The “Nuances Of Truth”: Communication And Uncertainty At An Environmental Journalists’ Workshop, Jen Schneider
Making Space For The “Nuances Of Truth”: Communication And Uncertainty At An Environmental Journalists’ Workshop, Jen Schneider
Jen Schneider
In 2008, the Society of Environmental Journalists listed nearly 50 science or science immersion workshops for environmental journalists. Yet relatively little is known about the content of these workshops and their impact on participants. This ethnographic study, conducted at a science immersion workshop for environmental journalists, aims to fill this void in our knowledge. Relying on participant observation and depth interviews, the study suggests that such workshops are useful for participating journalists: Reporters feel they leave the workshop better understanding the scientific method and scientific uncertainty. But the findings also reveal that “metacommunication”—communication about communication—is equally as important as science …
A Tutorial On The Basic Physics Of Climate Change, David W. Hafemeister, Peter V. Schwartz
A Tutorial On The Basic Physics Of Climate Change, David W. Hafemeister, Peter V. Schwartz
Peter V. Schwartz
In this paper, we have used several basic atmospheric–physics models to show that additional carbon dioxide will warm the surface of Earth. We also show that observed solar variations cannot account for observed global temperature increase.
The Synthesis Of Azaperylene-9,10-Dicarboximides, Brett Vanveller, Kojl Miki, Timorthy M. Swager
The Synthesis Of Azaperylene-9,10-Dicarboximides, Brett Vanveller, Kojl Miki, Timorthy M. Swager
Brett VanVeller
The efficient synthesis of a hydrophilic monomer bearing a three-dimensional noncompliant array of hydroxyl groups is described that prevents water-driven excimer features of hydrophobic poly(p-phenylene ethynylene) backbones. Sensitivity of the polymer to 3-nitrotyrosine is also discussesd.
Forward Modeling Synsedimentary Deformation Associated With A Prograding Steep-Sloped Carbonate Margin, Phillip G. Resor
Forward Modeling Synsedimentary Deformation Associated With A Prograding Steep-Sloped Carbonate Margin, Phillip G. Resor
Phillip G Resor
Differential compaction associated with prograding and aggrading steep-rimmed carbonate margins leads to penecontemporaneous and post- depositional modifications of stratal geometries and tensile and shear stress concentrations that result in brittle deformation. In an effort to investigate controls on these deformation processes, we employ a step-wise gravity loaded elastic model that captures pre-failure displacement and stress field patterns for a depositional geometry based on the Permian Capitan depositional system, Guadalupe Mountains, West Texas and New Mexico, USA. We consider four model geometries with varying progradation to aggradation (P/A) ratio, from strongly prograding (P/A=10) to strongly aggrading (P/A=0.1). The strongly prograding case …