Resource Type

103 Matching Results

Results open in a new window/tab.

Fermiology of the organic superconductor {beta}''-(ET){sub 2}SF{sub 5}CH{sub 2}CF{sub 2}SO{sub 3}. (open access)

Fermiology of the organic superconductor {beta}''-(ET){sub 2}SF{sub 5}CH{sub 2}CF{sub 2}SO{sub 3}.

We present a detailed Fermi-surface (FS) investigation of the quasi two-dimensional (2D) organic superconductor (T{sub c} {approx} 4.5 K) {beta}{double_prime}(ET){sub 2}SF{sub 5}CH{sub 2}CF{sub 2}SO{sub 3}. In line with previous investigations, de Haas-van Alphen measurements in pulsed fields up to 60 T show a single oscillation frequency, F{sub 0} = 200 T, which corresponds to a FS size of about 5% of the first Brillouin zone. Angular dependent magnetoresistance oscillations (AMROs) are utilized for the exact determination of the in-plane FS, which is found to be a strongly elongated ellipsoid with an axes ratio of about 1:9. Transport measurements in static fields up to 33 T show an unusual temperature dependence of the Shubnikov-de Haas (SdH) signal, i.e., a decrease of the SdH amplitude with decreasing temperature.
Date: July 29, 1998
Creator: Wosnitza, J.
System: The UNT Digital Library
A comparative study of electrospun polyvinylidene fluoride and poly(vinylidenefluoride-co-trifluoroethylene) fiber webs: Mechanical properties, crystallinity, and piezoelectric properties (open access)

A comparative study of electrospun polyvinylidene fluoride and poly(vinylidenefluoride-co-trifluoroethylene) fiber webs: Mechanical properties, crystallinity, and piezoelectric properties

Article is a study examining the fabrication and characterization of electrospun randomly oriented and aligned grooved polyvinylidene fluoride (PVDF) and poly(vinylidenefluoride-co-trifluoroethylene) (PVDF-TrFE) fiber webs.
Date: July 29, 2020
Creator: Xu, Bugao; Zhang, Wenxin; Zaarour, Bilal; Zhu, Lei; Huang, Chen & Jin, Xiangyu
System: The UNT Digital Library
Considerations for Efficient Airflow Design in Cleanrooms (open access)

Considerations for Efficient Airflow Design in Cleanrooms

A high-performance cleanroom should provide efficient energy performance in addition to effective contamination control. Energy-efficient designs can yield capital and operational cost savings, and can be part of a strategy to improve productivity in the cleanroom industry. Based upon in-situ measurement data from ISO Class 5 clean rooms, this article discusses key factors affecting cleanroom air system performance and benefits of efficient airflow design in clean rooms. Cleanroom HVAC systems used in the semiconductor, pharmaceutical, and healthcare industries are very energy intensive, requiring large volumes of cleaned air to remove or dilute contaminants for satisfactory operations. There is a tendency, however, to design excessive airflow rates into cleanroom HVAC systems, due to factors such as design conservatism, lack of thorough understanding of airflow requirements, concerns about cleanliness reliability, and potential design and operational liabilities. Energy use of cleanroom environmental systems varies with system type and design, cleanroom functions, and the control of critical parameters such as temperature and humidity. In particular, cleanroom cleanliness requirements specified by cleanliness class have an impact on overall energy use. A previous study covering Europe and the US reveals annual cleanroom electricity usage for cooling and fan energy varies significantly depending on cleanliness class, and …
Date: July 29, 2004
Creator: Xu, Tengfang
System: The UNT Digital Library
Spectroscopy of few-particle nuclei around magic {sup 132}Sn from fission product {gamma}-ray studies. (open access)

Spectroscopy of few-particle nuclei around magic {sup 132}Sn from fission product {gamma}-ray studies.

We are studying the yrast structure of very neutron-rich nuclei around doubly magic {sup 132}Sn by analyzing fission product {gamma}-ray data from a {sup 248}Cm source at Eurogam II. Yrast cascades in several few-valence-particle nuclei have been identified through {gamma}{gamma} cross coincidences with their complementary fission partners. Results for two-valence-particle nuclei {sup 132}Sb, {sup 134}Te, {sup 134}Sb and {sup 134}Sn provide empirical nucleon-nucleon interactions which, combined with single-particle energies already known in the one-particle nuclei, are essential for shell-model analysis in this region. Findings for the N = 82 nuclei {sup 134}Te and {sup 135}I have now been extended to the four-proton nucleus {sup 136}Xe. Results for the two-neutron nucleus {sup 134}Sn and the N = 83 isotones {sup 134}Sb, {sup 135}Te and {sup 135}I open up the spectroscopy of nuclei in the northeast quadrant above {sup 132}Sn.
Date: July 29, 1998
Creator: Zhang, C. T.
System: The UNT Digital Library
Measurement of the t{bar t} cross section at {radical}s = 1.96 TeV (open access)

Measurement of the t{bar t} cross section at {radical}s = 1.96 TeV

A measurement of the t{bar t} cross section at {radical}s = 1.96 TeV is carried out on data samples of {approx}40 pb{sup -1} in dilepton channels (e{mu}, ee and {mu}{mu}) and lepton+jets channels using two complementary approaches: a fully topological analysis and a soft-muon-tag. Overall, 17 events are observed with an expected background of 6.5 {+-} 0.6. This excess corresponds to an observation probability of three standard deviations and the measured t{bar t} cross section is: {sigma}{sub p}{bar p}{yields} t{bar t} = 8.5{sub -3.6}{sup +4.5} (stat) {sub -3.5}{sup +6.3} (sys) {+-} 0.8 (lumi) pb.
Date: July 29, 2003
Creator: al., Victor Abazov et
System: The UNT Digital Library
Overview of the SuperNova/Acceleration probe (SNAP) (open access)

Overview of the SuperNova/Acceleration probe (SNAP)

The SuperNova/Acceleration Probe (SNAP) is a space-based experiment to measure the expansion history of the Universe and study both its dark energy and the dark matter. The experiment is motivated by the startling discovery that the expansion of the Universe is accelerating. A 0.7 square-degree imager comprised of 36 large format fully-depleted n-type CCD's sharing a focal plane with 36 HgCdTe detectors forms the heart of SNAP, allowing discovery and lightcurve measurements simultaneously for many supernovae. The imager and a high-efficiency low-resolution integral field spectrograph are coupled to a 2-m three mirror anastigmat wide-field telescope, which will be placed in a high-earth orbit. The SNAP mission can obtain high-signal-to-noise calibrated light-curves and spectra for over 2000 Type Ia supernovae at redshifts between z = 0.1 and 1.7. The resulting data set can not only determine the amount of dark energy with high precision, but test the nature of the dark energy by examining its equation of state. In particular, dark energy due to a cosmological constant can be differentiated from alternatives such as ''quintessence'', by measuring the dark energy's equation of state to an accuracy of {+-} 0.05, and by studying its time dependence.
Date: July 29, 2002
Creator: galdering@lbl.gov
System: The UNT Digital Library
Appalachian Rivers II Conference: Technology for Monitoring, Assessing, and Restoring Streams, Rivers, and Watersheds (open access)

Appalachian Rivers II Conference: Technology for Monitoring, Assessing, and Restoring Streams, Rivers, and Watersheds

On July 28-29, 1999, the Federal Energy Technology Center (FETC) and the WMAC Foundation co-sponsored the Appalachian Rivers II Conference in Morgantown, West Virginia. This meeting brought together over 100 manufacturers, researchers, academicians, government agency representatives, watershed stewards, and administrators to examine technologies related to watershed assessment, monitoring, and restoration. Sessions included presentations and panel discussions concerning watershed analysis and modeling, decision-making considerations, and emerging technologies. The final session examined remediation and mitigation technologies to expedite the preservation of watershed ecosystems.
Date: July 29, 1999
Creator: unknown
System: The UNT Digital Library