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Report in Response to America COMPETES Act: SEC. 7022

Description: This report is written in response to the America COMPETES Act request that the NSF Director report on the NSF broader impact merit review criterion. This report includes background on the NSF implementation of the broader impact criterion and responds to each of the five specific requests made in the COMPETES Act Sec 7022.
Date: 2008
Creator: National Science Foundation (U.S.)
Partner: UNT Libraries Government Documents Department

Our changing planet: The FY 1994 US Global Change Research Program

Description: The approach of the US Global Change Research Program recognizes the profound economic and social implications of responding to global envirorunental changes and advances US leadership on this issue. The report outlines a careful blend of ground- and space-based efforts in research, data gathering, and modeling activities, as well as economic research, with both near- and long-term scientific and public policy benefits. In FY 1994, the Program will add an explicit focus on assessment, seeking to improve our understanding of the state of scientific knowledge and the implications of that knowledge for national and international policymaking activities.
Date: September 1, 1993
Partner: UNT Libraries Government Documents Department

Base isolation: Fresh insight

Description: The objective of the research is a further development of the engineering concept of seismic isolation. Neglecting the transient stage of seismic loading results in a widespread misjudgement: The force of resistance associated with velocity is mostly conceived as a source of damping vibrations, though it is an active force at the same time, during an earthquake type excitation. For very pliant systems such as base isolated structures with relatively low bearing stiffness and with artificially added heavy damping mechanism, the so called `damping`` force may occur even the main pushing force at an earthquake. Thus, one of the two basic pillars of the common seismic isolation philosophy, namely, the doctrine of usefulness and necessity of a strong damping mechanism, is turning out to be a self-deception, sometimes even jeopardizing the safety of structures and discrediting the very idea of seismic isolation. There is a way out: breaking with damping dependancy.
Date: July 15, 1993
Creator: Shustov, V.
Partner: UNT Libraries Government Documents Department

The growth, structure, and thermal stability of vapor deposited ultra-thin metal films: Rh on Ag(100), Au on Pd(110), and Pt on Pd(110)

Description: The growth, structure, and thermal stability of ultra-thin metal films (Rh on Ag(100); Au on Pd(110) and Pt on Pd(110)) is investigated using surface sensitive techniques. The three systems studied present a variety of differing characteristics which can contribute to the growth mode, two-dimensional structure, and thermal stability of the films. The main factors contributing to the differing properties of the three systems presented here are: (1) the different substrate morphologies; (2) the differences in surface free energies between the overlayer and the substrate; (3) the degree of lattice mismatch for a particular system; and (4) the extent of miscibility of the two metals. 200 refs., 38 figs.
Date: September 21, 1990
Creator: Schmitz, P.
Partner: UNT Libraries Government Documents Department

Ethics Gaming Survey Results

Description: Dataset generated for a National Science Foundation grant project, "EAGER: Prototyping a Virtue Ethics Game." These files contain the research results of the pre-test and post-test surveys.
Date: August 29, 2013
Creator: Oppong, Joseph R.
Partner: UNT College of Arts and Sciences

NMR studies of DNA oligomers and their interactions with minor groove binding ligands

Description: The cationic peptide ligands distamycin and netropsin bind noncovalently to the minor groove of DNA. The binding site, orientation, stoichiometry, and qualitative affinity of distamycin binding to several short DNA oligomers were investigated by NMR spectroscopy. The oligomers studied contain A,T-rich or I,C-rich binding sites, where I = 2-desaminodeoxyguanosine. I{center_dot}C base pairs are functional analogs of A{center_dot}T base pairs in the minor groove. The different behaviors exhibited by distamycin and netropsin binding to various DNA sequences suggested that these ligands are sensitive probes of DNA structure. For sites of five or more base pairs, distamycin can form 1:1 or 2:1 ligand:DNA complexes. Cooperativity in distamycin binding is low in sites such as AAAAA which has narrow minor grooves, and is higher in sites with wider minor grooves such as ATATAT. The distamycin binding and base pair opening lifetimes of I,C-containing DNA oligomers suggest that the I,C minor groove is structurally different from the A,T minor groove. Molecules which direct chemistry to a specific DNA sequence could be used as antiviral compounds, diagnostic probes, or molecular biology tools. The author studied two ligands in which reactive groups were tethered to a distamycin to increase the sequence specificity of the reactive agent.
Date: May 1, 1996
Creator: Fagan, P.A.
Partner: UNT Libraries Government Documents Department

Microbial ecology of terrestrial Antarctica: Are microbial systems at risk from human activities?

Description: Many of the ecological systems found in continental Antarctica are comprised entirely of microbial species. Concerns have arisen that these microbial systems might be at risk either directly through the actions of humans or indirectly through increased competition from introduced species. Although protection of native biota is covered by the Protocol on Environmental Protection to the Antarctic Treaty, strict measures for preventing the introduction on non-native species or for protecting microbial habitats may be impractical. This report summarizes the research conducted to date on microbial ecosystems in continental Antarctica and discusses the need for protecting these ecosystems. The focus is on communities inhabiting soil and rock surfaces in non-coastal areas of continental Antarctica. Although current polices regarding waste management and other operations in Antarctic research stations serve to reduce the introduction on non- native microbial species, importation cannot be eliminated entirely. Increased awareness of microbial habitats by field personnel and protection of certain unique habitats from physical destruction by humans may be necessary. At present, small-scale impacts from human activities are occurring in certain areas both in terms of introduced species and destruction of habitat. On a large scale, however, it is questionable whether the introduction of non-native microbial species to terrestrial Antarctica merits concern.
Date: August 1, 1996
Creator: White, G.J.
Partner: UNT Libraries Government Documents Department

Electromagnetic waves in a strong Schwarzschild plasma

Description: The physics of high frequency electromagnetic waves in a general relativistic plasma with the Schwarzschild metric is studied. Based on the 3 + 1 formalism, we conformalize Maxwell`s equations. The derived dispersion relations for waves in the plasma contain the lapse function in the plasma parameters such as in the plasma frequency and cyclotron frequency, but otherwise look {open_quotes}flat.{close_quotes} Because of this property this formulation is ideal for nonlinear self-consistent particle (PIC) simulation. Some of the physical consequences arising from the general relativistic lapse function as well as from the effects specific to the plasma background distribution (such as density and magnetic field) give rise to nonuniform wave equations and their associated phenomena, such as wave resonance, cutoff, and mode-conversion. These phenomena are expected to characterize the spectroscopy of radiation emitted by the plasma around the black hole. PIC simulation results of electron-positron plasma are also presented.
Date: November 1, 1996
Creator: Daniel, J. & Tajima, T.
Partner: UNT Libraries Government Documents Department

Copper Mountain conference on multigrid methods. Preliminary proceedings -- List of abstracts

Description: This report contains abstracts of the papers presented at the conference. Papers cover multigrid algorithms and applications of multigrid methods. Applications include the following: solution of elliptical problems; electric power grids; fluid mechanics; atmospheric data assimilation; thermocapillary effects on weld pool shape; boundary-value problems; prediction of hurricane tracks; modeling multi-dimensional combustion and detailed chemistry; black-oil reservoir simulation; image processing; and others.
Date: December 31, 1995
Partner: UNT Libraries Government Documents Department

Mitigation of earthquake hazards using seismic isolation systems

Description: This paper describes mitigation of earthquake hazards using seismic base isolation systems. A numerical algorithm for analyzing system response of base-isolated structures with laminated elastomer bearings is briefly described. Seismic response analyses of both base- isolated and unisolated buildings under earthquakes {number_sign}42 and {number_sign}44 are performed and the results are compared to illustrate the mitigating effect of base-isolated systems.
Date: June 1, 1996
Creator: Wang, C.-Y.
Partner: UNT Libraries Government Documents Department

Computational modeling of material aging effects

Description: Progress is being made in our efforts to develop computational models for predicting material property changes in weapon components due to aging. The first version of a two-dimensional lattice code for modeling thermomechanical fatigue, such as has been observed in solder joints on electronic components removed from the stockpile, has been written and tested. The code does a good qualitative job of presenting intergranular and/or transgranular cracking in a polycrystalline material when under thermomechanical deformation. The current progress is an encouraging start for our long term effort to develop multi-level simulation capabilities, with the technology of high performance computing, for predicting age-related effects on the reliability of weapons.
Date: July 1, 1996
Creator: Fang, H.E.
Partner: UNT Libraries Government Documents Department

The Promise and Perils of Transformative Research

Description: This report is on the workshop 'Transformative Research: Ethical and Societal Implications'. Workshop conversations cluster under the four headings of the history and definitions, promotion, evaluation, and integration of transformative research.
Date: March 2012
Creator: Frodeman, Robert & Holbrook, J. Britt
Partner: UNT College of Arts and Sciences

[Atomic and electronic structure of metals and alloys: Clean surfaces and chemisorbed molecules]

Description: Ultrapure Tb was further purified and surface cleaning procedures developed for basal plane and (11[bar 2]0) surface of Tb. Structure of both surfaces was found to be relaxed: (0001) is contracted by 3.9% in the first and expanded by 1.4% in second interlayer spacing; (11[bar 2]0) is contracted by 3.3% in first layer and shows a change in registry. Thin films of Gd, Tb, Dy, Ho, and Er were grown on W[l brace]110[r brace] substrate in ultrahigh vacuum. Studies have been carried out on epitaxial systems involving Cu, Fe and Mn on Fe and Pt, Cu, and Pd substrates, respectively; new metastable crystalline phases have been found. Studies of possible ferromagnetism in 4d elements (Rh, Ru) and relativistic effects in electron band structure of Cu[l brace]111[r brace] have been completed and published. Plans for the following year are given.
Date: January 1, 1993
Partner: UNT Libraries Government Documents Department

Application of ground-penetrating radar at McMurdo Station, Antarctica

Description: Argonne National Laboratory initiated a site investigation program at McMurdo Station, Antarctica, to characterize environmental contamination. The performance and usefulness of ground-penetrating radar (GPR) was evaluated under antarctic conditions during the initial site investigation in January 1991. Preliminary surveys were successful in defining the contact between reworked pyroclastic material and in the prefill, undisturbed pyroclastics and basalts at some sites. Interference from radio traffic at McMurdo Station was not observed, but interference was a problem in work with unshielded antennas near buildings. In general, the results of this field test suggest that high-quality, high-resolution, continuous subsurface profiles can be produced with GPR over most of McMurdo Station.
Date: January 1, 1992
Creator: Stefano, J.E.
Partner: UNT Libraries Government Documents Department

Comparison of SISEC code simulations with earthquake data of ordinary and base-isolated buildings

Description: Seismic isolation is gaining attention worldwide for use in a wide spectrum of structures and critical facilities, including bridges, office buildings, hospitals, computing and telecommunication centers, as well as nuclear facilities. Today there are over 125 structures worldwide which are isolated and the numbers have been increasing steadily in the past few years. Also, substantial research efforts have been devoted to the designs, testing of isolation bearings, as well as development of analytical methods for predicting the responses of isolated structures. At Argonne National Laboratory (ANL), a 3-D computer program SISEC (Seismic Isolation System Evaluation Code) is being developed for simulating the system response of isolated and ordinary structures (Wang et al. 1991). This paper describes comparison of SISEC code simulations with building response data of actual earthquakes. To ensure the accuracy of analytical simulations, recorded data of full-size reinforced concrete structures located in Sendai, Japan are used in this benchmark comparison. The test structures consist of two three-story buildings, one base-isolated and the other one ordinary founded. They were constructed side by side to investigate the effect of base isolation on the acceleration response. Among 20 earthquakes observed since April 1989, complete records of three representative earthquakes, Nos. 2, 6, and 17, are used for the code validation presented in this paper. Correlations of observed and calculated accelerations at all instrument locations are made. Also, relative response characteristics of ordinary and isolated building structures are investigated. 3 refs., 5 figs., 1 tab.
Date: January 1, 1991
Creator: Wang, C.Y. & Gvildys, J.
Partner: UNT Libraries Government Documents Department

The National Teacher Enhancement Program (K-8) coordinated by the Oak Ridge National Laboratory

Description: Teachers need help, not harassment. So do the establishments in which teachers practice their profession. Community resources must be marshalled to provide help to local schools and teachers. In 1990 the National Science Foundation (NSF) established a unique educational activity named the National Teacher Enhancement Program (NTEP). NSF took advantage of the Department of Energy (DOE) sponsored educational programs and resources at several large DOE contractor labs that had had prior experience with DOE supported teacher enhancement programs. While DOE concentrated on teacher enhancement activities for secondary teachers, the NSF concentrated on teachers from grades K-8. The Oak Ridge National Laboratory (ORNL) is the lead organization for both administering and coordinating the grant. Other participating laboratories are Argonne National Laboratory (ANL), Fermi National Accelerator Laboratory (FERMI), Battelle-Pacific Northwest Laboratory (PNL), Lawrence Livermore Laboratory (LLNL) with some support functions provided by Brookhaven National Laboratory (BNL) and the Oak Ridge Associated Universities (ORAU). The program calls for a three week duration workshop to be conducted at each lab followed by in-service training and other activities during the year. The NSF/NTEP protocol calls for networking among the participating organizations and some of the teachers. An assessment effort is also an integral part of the program. 2 refs.
Date: January 1, 1991
Creator: Richmond, C.R.
Partner: UNT Libraries Government Documents Department

Nuclear/High Energy Physics (NuHEP) research center of excellence

Description: This report contains the manuscripts from the proceedings of the third annual Undergraduate Institute in Physics Program. The titles of these manuscripts are: flow measurements for the hall c cryogenic target loops; calibrations for the hall c drift chambers gas mixing system; the electromagnetic structure of the nucleon; investigation of drift chambers in hall c at CEBAF; seek and ye shall find; commissioning techniques; and instruments used in particle detection.
Date: December 31, 1994
Partner: UNT Libraries Government Documents Department

New Source of Natural Fertilizer Discovered in Oceans

Description: New findings suggest that the deep ocean is teeming with organisms that produce essential natural fertilizers. A National Science Foundation (NSF)-funded research team led by Jonathan Zehr, a marine scientist at the University of California, Santa Cruz, has discovered a previously unknown type of photosynthetic bacteria that fixes nitrogen, converting nitrogen from the atmosphere into a form other organisms can use.
Date: August 8, 2001
Creator: National Science Foundation (U.S.). Office of Legislative and Public Affairs.
Partner: UNT Libraries

Measurements of the summer surface heat budget of the Northeast Water Polynya. USCGC Polar Sea cruise, July 15--August 15, 1992

Description: A research cruise of the USCGC Polar Sea to the Northeast Water Polynya, off the eastern coast of Greenland (77--81{degree}N, 6--17{degree}W), was made from mid-July to mid-August of 1992 (NEWP `92) as the first field component of the multi-disciplinary study of a high-Arctic polynya funded by the NSF as part of the Arctic Systems Science program. Instruments to measure the components of the surface heat budget of the polynya were installed on a foremast at the bow of the ship. This report presents the measured variables and derived surface fluxes in graphical and tabulated form. Profiles of atmospheric temperature and humidity were taken using radiosondes, and these are also presented.
Date: March 1, 1994
Creator: Minnett, P. J.
Partner: UNT Libraries Government Documents Department

Results of PM{sub 10} and TSP monitoring at McMurdo Station, Antarctica

Description: This report presents the results of ambient air monitoring of particulate matter performed during the 1992-1993 austral summer in the vicinity of McMurdo Station, Antarctica. Thirty three 24-hour samples were collected from three locations for determination of the concentration of particulate matter less that 10 micrometers (PM{sub 10}), and seven samples collected for determination of total suspended particulate matter (TSP) concentration. Critical flow high volume air samplers with a sample flow rate of approximately 1.1 m{sup 3}/min. were used to collect the particulate matter on quartz fiber filters for subsequent gravimetric analysis. Sampling site selection, sampling procedures, and quality assurance procedures used were consistent with US Environmental Protection Agency guidance for local ambient air quality networks. Mean austral summer PM{sub 10} levels in the McMurdo locale were 3 {mu}g/m{sup 3} at the predominantly upwind location, 9 {mu}g/m{sup 3} at a location approximately 500 meters downwind of the station, and 16 {mu}g/m{sup 3} at a {open_quotes}downtown{close_quotes} location. All PM{sub 10} results were below the US National Ambient Air Quality Standard. TSP results at all locations were greater than PM{sub 10} concentrations; ranging from 8 {mu}g/m{sup 3} at the upwind location to a maximum measurement of 276 {mu}g/m{sup 3} at the {open_quotes}downtown{close_quotes} location. The initial baseline effort demonstrated that site selection and sampling equipment performance were satisfactory, and provided useful data for assessing the impact of McMurdo operations on the local ambient air quality.
Date: May 1, 1993
Creator: Lugar, R. M.
Partner: UNT Libraries Government Documents Department

Application of ground-penetrating radar at McMurdo Station, Antarctica

Description: Argonne National Laboratory initiated a site investigation program at McMurdo Station, Antarctica, to characterize environmental contamination. The performance and usefulness of ground-penetrating radar (GPR) was evaluated under antarctic conditions during the initial site investigation in January 1991. Preliminary surveys were successful in defining the contact between reworked pyroclastic material and in the prefill, undisturbed pyroclastics and basalts at some sites. Interference from radio traffic at McMurdo Station was not observed, but interference was a problem in work with unshielded antennas near buildings. In general, the results of this field test suggest that high-quality, high-resolution, continuous subsurface profiles can be produced with GPR over most of McMurdo Station.
Date: May 1, 1992
Creator: Stefano, J. E.
Partner: UNT Libraries Government Documents Department

Numerical simulation of seismic response of a base isolated building with low shear modulus rubber isolators

Description: This paper describes seismic-response simulations of a base-isolated building subjected to actual earthquakes using the 3-D computer program, SISEC, developed at Argonne National Laboratory. The isolation system consists of six medium shape factor, high damping, and low shear modulus rubber bearings. To ensure the accuracy of analytical simulation, recorded data of full-size reinforced concrete structures located in Sendai, Japan are used as the benchmarks for comparisons of numerical simulations with observations. Results obtained from both analytical simulations and earthquake observations indicate that the advantage of base isolation in mitigating the acceleration of superstructure is very pronounced. For the two representative earthquakes, one had the strongest ground motion and the other one had similar magnitudes as the rest of the earthquakes recorded at the test site, the simulated accelerations at the roof level of the isolated building are about 20% to 30% of the ordinary building accelerations. Also, results reveal that for both ordinary and base-isolated buildings the computed accelerations agree reasonably well with those recorded.
Date: June 1, 1993
Creator: Wang, C. Y.
Partner: UNT Libraries Government Documents Department

Results of SO{sub 2}, NO{sub x}, and CO monitoring at McMurdo Station, Antarctica

Description: This report presents the results of ambient air monitoring of carbon monoxide (CO), sulfur dioxide (SO{sub 2}), nitric oxide (NO), nitrogen dioxide (NO{sub 2}), and total oxides of nitrogen (NO{sub x}) performed during the final weeks of the 1992-1993 austral summer in the vicinity of McMurdo Station, Antarctica. Commercially available, high sensitivity ambient air gas analyzers were used to continuously measure gas concentrations at two locations over a two and a three week time period respectively. Sampling site selection, sampling procedures and quality assurance procedures used for this effort were consistent with U.S. Environmental Protection Agency guidelines for local ambient air quality networks. CO, SO{sub 2}, and NO{sub 2} concentrations measured were below the associated U.S. National Ambient Air Quality Standards. Carbon monoxide levels measured at both locations were near or below the instrument detection limit of 0.1 part per million (ppm). Hourly average SO{sub 2} concentrations ranged from below the detection limit of 1 part per billion (ppb) to a single maximum hourly average value of 60 ppb. Hourly average NO{sub 2} concentrations ranged from below the detection limit of 1 ppb to a single maximum hourly average value of 26 ppb. The impact on local air quality of ships docked at an ice pier was observed and quantified. The initial baseline effort demonstrated that site selection and sampling equipment performance were satisfactory, and provided useful data for assessing the impact of McMurdo operations on the local ambient air quality.
Date: May 1, 1993
Creator: Lugar, R. M.
Partner: UNT Libraries Government Documents Department