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On the Mechanism of Generation of Magneto-Hydrodynamic Whirl Rings in the Interior of the Sun and Their Relation to Sunspots, Faculae, Prominences, and Flares

Description: Abstract: "A possible mechanism for the generation of magneto-hydrodynamic whirl rings near the center of the sun is described. The organic relation of the reflection of these whirl rings at the surface of the sun to the cooling of sunspots, orientation, and polarity sequence of sunspots, prominences, flares, and faculae is delineated."
Date: March 29, 1955
Creator: Bostick, W. H.
Partner: UNT Libraries Government Documents Department

EXTINCTION OF SPECIES BY PERIODIC COMET SHOWERS

Description: A 26-Myr periodicity has recently been seen in the fossil record of extinction in the geological past. At least two of these extinctions are known to be associated with the impact on the Earth of a comet or asteroid with a diameter of a few kilometres. We propose that the periodic events are triggered by an unseen companion to the Sun, travelling in a moderately eccentric orbit, which at its closest approach (perihelion) passes through the 'Oort cloud' of comets which surrounds the Sun. During each passage this unseen solar companion perturbs the orbits of these comets, sending a large number of them (over 1 x 10{sup 9}) into paths which reach the inner Solar System. Several of these hit the Earth, on average, in the following million years. At present the unseen companion should be approximately at its maximum distance from the Sun, {approx}2.4 light yr, and it will present no danger to the Earth until approximately AD 15,000,000.
Date: January 1, 1984
Creator: Davis, M.; Hut, P. & Muller, R.A.
Partner: UNT Libraries Government Documents Department

Coronal structure inferred from remote sensing observations

Description: Remote-sensing observations of the Sun and inner heliosphere are reviewed to appraise our understanding of the mix of the mechanisms that heat the corona and accelerate the solar wind. An assessment of experimental uncertainties and the basic assumptions needed to translate measurables into physical models, reveals very large fundamental uncertainties in our knowledge of coronal structure near the Sun. We develop a time-dependent, filamentary model of the extended corona that is consistent with a large number of remote sensing observations of the solar atmosphere and the solar wind.
Date: September 1, 1996
Creator: Feldman, W.C.
Partner: UNT Libraries Government Documents Department

Soft Sun Cells

Description: Representing the Argonne-Northwestern Solar Energy Research (ANSER) Center, this document is one of the entries in the Ten Hundred and One Word Challenge. As part of the challenge, the 46 Energy Frontier Research Centers were invited to represent their science in images, cartoons, photos, words and original paintings, but any descriptions or words could only use the 1000 most commonly used words in the English language, with the addition of one word important to each of the EFRCs and the mission of DOE: energy. The mission of ANSER is to revolutionize our understanding of molecules, materials and methods necessary to create dramatically more efficient technologies for solar fuels and electricity production.
Date: July 18, 2013
Creator: Shastry, Tejas
Partner: UNT Libraries Government Documents Department

Southern Great Plains Newsletter, September 2010

Description: Monthly newsletter of Argonne National Laboratory. This month's issue contains the following articles: (1) Scientists convene at SGP site for complex convective cloud experiment; (2) VORTEX2 spins down; (3) Sunphotometer supports SPARTICUS (a Sun and Aureole Measurement imaging sunphotometer) campaign and satellite validation studies; and (4) Ceilometer represents first deployment of new ground-based instruments from Recovery Act.
Date: September 2010
Creator: Argonne National Laboratory
Partner: UNT Libraries Government Documents Department

Measuring solar abundances

Description: This is the rapporteur paper of Working Group 2 on Measuring Solar Abundances. The working group presented and discussed the different observations and methods for obtaining the elemental and isotopic composition of the Sun, and critically reviewed their results and the accuracies thereof. Furthermore, a few important yet unanswered questions were identified, and the potential of future missions to provide answers was assessed.
Date: January 1, 2001
Creator: Reisenfeld, D. B. (Daniel B.); Von Steiger, R. (Rudolf); Vial, J.-C. (Jean-Claude); Bochsler, P.; Chaussidon, M.; Cohen, C. M. S. et al.
Partner: UNT Libraries Government Documents Department

Sustainable Energy Solutions for Water Purification Applications: Municipal and Industrial Case Studies

Description: In several areas around the world, clean water is a precious asset that at anytime, and mainly due to circumstances of weather and climate, can become scarce. Mainly in the dry and remote places, people suffer with lack of water. A solution for this suffering can be a water desalination system, which makes water potable and usable for industry. That solution inherently, brings the problem of power requirement, which is sometimes arduous to accomplish in such remote areas of difficult access and long distances to overcome to build the infrastructure required to operate an electric power plant. Texas and the USA also face this scenario for many regions, for which the government has been creating some programs and driving forward incentives, looking for solutions to support water desalination. Water desalination has future applications for municipalities water-consuming or for arid and remote regions, as well as for industries that rely on heavy water usage, such as natural gas drilling operations, for which millions of gallons are trucked overland to the site and also hauled away afterwards, when the waste water produced must be treated. This thesis created the concept of autonomy for water desalination plants replacing the actual power supply from fossil fuel to a renewable source from wind or sun, giving capacity to them to produce its own electricity to operate as an autonomous unit, as demonstrated in the business case done for the Brownsville water desalination facility.
Date: May 2014
Creator: Mira, Sebastião Bittencourt de
Partner: UNT Libraries

Delta Scuti stars: Theory

Description: The purpose of asteroseismology is not only to derive the internal structure of individual stars from their observed oscillation frequencies, but also to test and extend one`s understanding of the physics of matter under the extremes of temperature, density, and pressure found in stellar interiors. In this review, the author hopes to point out what one can learn about the Sun by studying {delta} Scuti stars, as well as what one can learn about stars more massive or evolved than the Sun. He discusses some of the difficulties in theoretical approaches to asteroseismology for {delta} Scuti stars, using FG Vir, {delta} Scuti, and CD-24{degree} 7599 as examples.
Date: March 1, 1998
Creator: Guzik, J.A.
Partner: UNT Libraries Government Documents Department

What have we learned about the solar interior from solar oscillations?

Description: After a brief review of the discovery and properties of solar oscillations, I summarize the significant advances in our knowledge of the Sun`s interior structure achieved by using solar oscillation frequency data. I discuss the surprising solar interior rotation profile; the precise determination of the convection zone depth; the convection zone helium abundance; evidence for diffusive settling of helium during the Sun`s 4.5 billion year lifetime; and the Sun`s central structure and implications for the solar neutrino problem.
Date: December 31, 1995
Creator: Guzik, J.A.
Partner: UNT Libraries Government Documents Department

Connection to Nature

Description: Lesson plan containing a collection of activities and resources regarding connections to nature that meet state education standards and national sustainability standards for the kindergarten grade level.
Date: August 6, 2014
Creator: Treadway, Heather
Partner: UNT Office of Sustainability

Solar variability observed through changes in solar limb-darkening function and mean diameter. Final report, February 1, 1987--August 31, 1993

Description: The advantages of a dedicated, ground-based observatory over measurements from spacecraft are its relative adaptability, ease of maintenance, and low cost. However, groundbased observations must contend with problems introduced by observing through the Ear-th`s atmosphere and by changes in the long-term stability of the observing instrument. Both of these problems have been addressed at SCLERA and currently pose no limitation of solar diameter measurements at the parts-per-n-tillion level. The atmospheric problems of seeing and differential refraction are managed by separate procedures. For the former, a technique is used for the definition of the edge of a solar limb which exhibits a greatly reduced sensitivity to atmospheric seeing (Hill, Stebbins, and Oleson 1975). For the latter, diameters measured at several solar latitudes are used to yield a solar oblateness and diameter with reduced sensitivity to differential refraction. Differential radius measurements are used to detect changes in the solar limb-darkening function with a reduced sensitivity to differential refraction. The long-term stability of the telescope is monitored with an interferometric technique which is itself stable over long periods of time. Exploration of information contained in the global oscillations of the Sun is the basis of solar seismology programs. Such exploration permits the examination of the internal structure of a star at an unprecedented level of detail and accuracy. Changes in the internal structure of the Sun relevant to changes in energy output can be detected through observing changes in the mode frequency of oscillation. This approach is also used at SCLERA in its study of long-term variability in solar irradiance.
Date: May 31, 1995
Creator: Hill, H.A.
Partner: UNT Libraries Government Documents Department

A Study of Sun Yat-sen's Propaganda Activities and Techniques in the United States During China's Revolutionary Period (1894-1911)

Description: Sun Yat-sen used six propaganda techniques in the United States to help overthrow the Ching Dynasty in 1911: (a) individual propaganda to gain supporters through personal contact and individual persuasion; (b) propaganda of deed to solicit donations and to mobilize his supporters for military actions; (c) travel propaganda to broaden the base of revolutionary support; (d) newspaper propaganda to publicize and explain his revolutionary program; (e) debate propaganda to refute antirevolutionary criticism through speeches and pamphlets; and (f) missionary propaganda to seek sympathy and support from American missionaries and Christians.
Date: December 1981
Creator: Chao, Nang-yung
Partner: UNT Libraries

[News Script: TCU]

Description: Script from the WBAP-TV/NBC station in Fort Worth, Texas, covering a broadcast news story.
Date: January 1, 1966
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

A Search for Neutrinos from the Solar hep Reaction and the DiffuseSupernova Neutrino Background with the Sudbury Neutrino Observatory

Description: A search has been made for neutrinos from the hep reactionin the Sun and from the diffuse supernova neutrino background (DSNB)using data collected during the first operational phase of the SudburyNeutrino Observatory, with an exposure of 0.65 kilotonne-years. For thehep neutrino search, two events are observed in the effective electronenergy range of 14.3 MeV<Teff<20 MeV where 3.1 backgroundevents are expected. After accounting for neutrino oscillations, an upperlimit of 2.3 x 104 cm-2s-1 at the 90 percent confidence level is inferredon the integral total flux of hep neutrinos. For DSNB neutrinos, noevents are observed in the effective electron energy range of 21 MeV<Teff<35 MeV and, consequently, an upper limit on the nu e componentof the DSNB fluxin the neutrino energy range of 22.9 MeV<E nu<36.9 MeV of 70 cm-2-1 is inferred at the 90 percent confidence level.This is an improvement by a factor of 6.5 on the previous best upperlimit on the hep neutrino flux and by two orders of magnitude on theprevious upper limit on the nu e component of the DSNB flux.
Date: August 1, 2006
Creator: Aharmim, B.; Ahmed, S.N.; Anthony, A.E.; Beier, E.W.; Bellerive,A.; Bergevin, M. et al.
Partner: UNT Libraries Government Documents Department

Recent vs from IceCube

Description: IceCube is a 1 km3 neutrino detector now being built at the South Pole. Its 4800 optical modules will detect Cherenkov radiation from charged particles produced in neutrino interactions. IceCube will search for neutrinos of astrophysical origin, with energies from 100 GeV up to 1019 eV. It will be able to separate nue, nu mu and nu tau. In addition to detecting astrophysical neutrinos, IceCube will also search for neutrinos from WIMP annihilation in the Sun and the Earth, look for low-energy (10 MeV) neutrinos from supernovae, and search for a host of exotic signatures. With the associated IceTop surface air shower array, it will study cosmic-ray air showers. IceCube construction is now 50percent complete. After presenting preliminary results from the partial detector, I will discuss IceCube's future plans.
Date: October 3, 2008
Creator: Collaboration, IceCube & Klein, Spencer R.
Partner: UNT Libraries Government Documents Department

Monitored Energy Performance of Electrochromic Windows Controlledfor Daylight and Visual Comfort

Description: A 20-month field study was conducted to measure the energy performance of south-facing large-area tungsten-oxide absorptive electrochromic (EC) windows with a broad switching range in a private office setting. The EC windows were controlled by a variety of means to bring in daylight while minimizing window glare. For some cases, a Venetian blind was coupled with the EC window to block direct sun. Some tests also involved dividing the EC window wall into zones where the upper EC zone was controlled to admit daylight while the lower zone was controlled to prevent glare yet permit view. If visual comfort requirements are addressed by EC control and Venetian blinds, a 2-zone EC window configuration provided average daily lighting energy savings of 10 {+-} 15% compared to the reference case with fully lowered Venetian blinds. Cooling load reductions were 0 {+-} 3%. If the reference case assumes no daylighting controls, lighting energy savings would be 44 {+-} 11%. Peak demand reductions due to window cooling load, given a critical demand-response mode, were 19-26% maximum on clear sunny days. Peak demand reductions in lighting energy use were 0% or 72-100% compared to a reference case with and without daylighting controls, respectively. Lighting energy use was found to be very sensitive to how glare and sun is controlled. Additional research should be conducted to fine-tune EC control for visual comfort based on solar conditions so as to increase lighting energy savings.
Date: September 23, 2005
Creator: Lee, Eleanor S.; DiBartolomeo, Dennis L.; Klems, Joseph; Yazdanian, Mehry & Selkowitz, Stephen E.
Partner: UNT Libraries Government Documents Department