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Correlation and Prediction of Partition Coefficients from the Gas Phase and from Water to Alkan-1-ols
Article discussing correlation and prediction of partition coefficients from the gas phase and from water to alkan-1-ols.
Date:
April 22, 2008
Creator:
Abraham, M. H. (Michael H.); Nasezadeh, Asadollah & Acree, William E. (William Eugene)
Object Type:
Article
System:
The UNT Digital Library
Polycube Oxidation and Factors Affecting the Concentrations of Gaseous Products
The degraded polycube samples were tested in air and argon/oxygen atmospheres to determine the effect of size increase on the flammable gases concentrations. Within the size range tested, the flammable gas generation rate increases with increasing size but the extrapolation of the data to actual processing polycube size yielded flammable gas species concentration in the off-gas stream below the lower flammable limit of all the major gas species identified. Extreme surface area increase with a powder sample showed no significant effect on the flammable gas generation rate. The polycube went through the thermal stabilization process by undergoing both pyrolysis and oxidation generating at the end a plutonium oxide powder that showed unmeasurable weight change at 1273 K.
Date:
April 4, 2000
Creator:
Abrefah, John; MacFarlan, Paul J. & Sell, Rachel L.
Object Type:
Text
System:
The UNT Digital Library
2006 Electrochemistry Gordon Research Conference - February 12-17-2006
This report is a descriptive journey of 2006 Electrochemistry Gordon Research Conference.
Date:
April 3, 2007
Creator:
Abruna, Hector D.
Object Type:
Article
System:
The UNT Digital Library
Evolution of Electronic Properties of (Cu(In,Ga)Se2 (CIGS)-Based Solar Cells During a 3-Stage Growth Process: Preprint
We investigated the electronic properties of ZnO/CdS/CIGS /Mo/SLG polycrystalline thin-film solar cells with compositions ranging from Cu-rich to In(Ga)-rich by deep-level transient spectroscopy (DLTS) and capacitance-voltage (C-V) measurements. This compositional change represents the evolution of the film during growth by the 3-stage process. Two sets (four samples each) of CIGS thin films were prepared with Ga/(In+Ga) ratios of~0.3 (low Ga) and~0.6 (high Ga). The Cu/(In+Ga) ratio ranges from 1.24 (Cu-rich) to 0.88 (In(Ga)-rich). The films were treated with NaCN to remove the Cu2-xSe phase where needed. Key results include: (1) For low-Ga devices, DLTS data show that acceptor-like traps dominate in samples where CIGS grains do not go through the Cu-rich to In(Ga)-rich transition, whereas donor-like traps dominate in In(Ga)-rich samples. Therefore, we see a clear transformation of defects from acceptor-like to donor-like traps. The activation energies of these traps range from 0.12 to 0.63 eV. We also observed that NaCN treatment eliminates a deep minority trap in the In(Ga)-rich devices, (2) For high-Ga devices, only majority-carrier traps were detected. These traps again range from shallow to deep, (3) The carrier concentration around the junction and the density of traps decrease as the CIGS becomes more In(Ga)-rich.
Date:
April 1, 2003
Creator:
AbuShama, J. A.; Johnston, S.; Ahrenkiel, R.; Crandall, R.; Young, D. & Noufi, R.
Object Type:
Article
System:
The UNT Digital Library
Search for Large Extra Dimensions in the Production of Jets and Missing Transverse Energy in ppbar Collisions at s**(1/2) = 1.96 TeV
The authors present the results of a search for new physics in the jets plus missing transverse energy data sample collected from 368 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV recorded by the Collider Detector at Fermilab. They compare the number of events observed in the data with a data-based estimate of the standard model backgrounds contributing to this signature. They observe no significant excess of events, and they interpret this null result in terms of lower limits on the fundamental Planck scale for a large extra dimensions scenario.
Date:
April 1, 2006
Creator:
Abulencia, A.; Acosta, D.; Adelman, Jahred A.; Affolder, T.; Akimoto, T.; Albrow, M.G. et al.
Object Type:
Article
System:
The UNT Digital Library
Polarization of J / psi and psi(2S) mesons produced in p anti-p collisions at s**(1/2) = 1.96-TeV
The authors have measured the polarizations of J/{psi} and {psi}(2S) mesons as functions of their transverse momentum p{sub T} when they are produced promptly in the rapidity range |y| < 0.6 with p{sub T} {ge} 5 GeV/c. The analysis is performed using a data sample with an integrated luminosity of about 800 pb{sup -1} collected by the CDF II detector. For both vector mesons, they find that the polarizations become increasingly longitudinal as p{sub T} increases from 5 to 30 GeV/c. These results are compared to the predictions of non-relativistic quantum chromo-dynamics and other contemporary models. The polarizations of J/{psi} and {psi}(2S) mesons from B-hadron decays are also reported.
Date:
April 1, 2007
Creator:
Abulencia, A.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M. G.; Amerio, S. et al.
Object Type:
Article
System:
The UNT Digital Library
Search for heavy, long-lived particles that decay to photons at CDF II
The authors present the first search for heavy, long-lived particles that decay to photons at a hadron collider. They use a sample of {gamma} + jet + missing transverse energy events in p{bar p} collisions at {radical}s = 1.96 TeV taken with the CDF II detector. Candidate events are selected based on the arrival time of the photon at the detector. Using an integrated luminosity of 570 pb{sup -1} of collision data, they observe 2 events, consistent with the background estimate of 1.3 {+-} 0.7 events. While the search strategy does not rely on model-specific dynamics, they set cross section limits in a supersymmetric model with {tilde {chi}}{sub 1}{sup 0} {yields} {gamma}{tilde G} and place the world-best 95% C.L. lower limit on the {tilde {chi}}{sub 1}{sup 0} mass of 101 GeV/c{sup 2} at {tau}{sub {tilde {chi}}{sub 1}{sup 0}} = 5 ns.
Date:
April 1, 2007
Creator:
Abulencia, A.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M. G.; Amerio, S. et al.
Object Type:
Article
System:
The UNT Digital Library
Analysis of Homogeneous Charge Compression Ignition (HCCI) Engines for Cogeneration Applications
This paper presents an evaluation of the applicability of Homogeneous Charge Compression Ignition Engines (HCCI) for small-scale cogeneration (less than 1 MWe) in comparison to five previously analyzed prime movers. The five comparator prime movers include stoichiometric spark-ignited (SI) engines, lean burn SI engines, diesel engines, microturbines and fuel cells. The investigated option, HCCI engines, is a relatively new type of engine that has some fundamental differences with respect to other prime movers. Here, the prime movers are compared by calculating electric and heating efficiency, fuel consumption, nitrogen oxide (NOx) emissions and capital and fuel cost. Two cases are analyzed. In Case 1, the cogeneration facility requires combined power and heating. In Case 2, the requirement is for power and chilling. The results show that the HCCI engines closely approach the very high fuel utilization efficiency of diesel engines without the high emissions of NOx and the expensive diesel fuel. HCCI engines offer a new alternative for cogeneration that provides a unique combination of low cost, high efficiency, low emissions and flexibility in operating temperatures that can be optimally tuned for cogeneration systems. HCCI engines are the most efficient technology that meets the oncoming 2007 CARB NOx standards for cogeneration …
Date:
April 30, 2004
Creator:
Aceves, S; Martinez-Frias, J & Reistad, G
Object Type:
Article
System:
The UNT Digital Library
ENSO Simulation in Coupled Ocean-Atmosphere Models: Are the Current Models Better?
Maintaining a multi-model database over a generation or more of model development provides an important framework for assessing model improvement. Using control integrations, we compare the simulation of the El Nino/Southern Oscillation (ENSO), and its extratropical impact, in models developed for the 2007 Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report with models developed in the late 1990's (the so-called Coupled Model Intercomparison Project-2 [CMIP2] models). The IPCC models tend to be more realistic in representing the frequency with which ENSO occurs, and they are better at locating enhanced temperature variability over the eastern Pacific Ocean. When compared with reanalyses, the IPCC models have larger pattern correlations of tropical surface air temperature than do the CMIP2 models during the boreal winter peak phase of El Nino. However, for sea-level pressure and precipitation rate anomalies, a clear separation in performance between the two vintages of models is not as apparent. The strongest improvement occurs for the modeling groups whose CMIP2 model tended to have the lowest pattern correlations with observations. This has been checked by subsampling the multi-century IPCC simulations in a manner to be consistent with the single 80-year time segment available from CMIP2. Our results suggest that multi-century …
Date:
April 29, 2005
Creator:
AchutaRao, K. & Sperber, K. R.
Object Type:
Article
System:
The UNT Digital Library
Education Vouchers: Constitutional Issues and Cases
This report details the constitutional standards that currently apply to indirect aid programs and summarizes all of the pertinent state and federal court decisions, including the Ohio case that will be heard by the Supreme Court. On September 25, 2001, the Supreme Court agreed to review a case raising the controversial issue of the constitutionality of education vouchers. In Zelman v. Simmons-Harris the Sixth Circuit held Ohio’s Pilot Scholarship Program, which provided up to $2500 to help low-income students in Cleveland’s public schools attend private schools in the city, to violate the establishment of religion clause of the First Amendment.
Date:
April 8, 2003
Creator:
Ackerman, David M.
Object Type:
Report
System:
The UNT Digital Library
International Law and the Preemptive Use of Force Against Iraq
None
Date:
April 11, 2003
Creator:
Ackerman, David M.
Object Type:
Report
System:
The UNT Digital Library
B physics: measurement of partial widths and search for direct cp violation in d0 meson decays
We present a measurement of relative partial widths and decay rate CP asymmetries in K{sup -}K{sup +} and {pi}{sup -}{pi}{sup +} decays of D{sup 0} mesons produced in p{bar p} collisions at {radical}s = 1.96TeV. We use a sample of 2 x 10{sup 5} D*{sup +} {yields} D{sup 0}{pi}{sup +} (and charge conjugate) decays with the D{sup 0} decaying to K{sup -}{pi}{sup +}, K{sup -}K{sup +}, and {pi}{sup -}{pi}{sup +}, corresponding to 123 pb{sup -1} of data collected by the Collider Detector at Fermilab II experiment at the Fermilab Tevatron collider. No significant direct CP violation is observed. We measure {Lambda}(D{sup 0} {yields} K{sup -}K{sup +})/{Lambda}(D{sup 0} {yields} K{sup -}{pi}{sup +}) = 0.0992 {+-} 0.0011 {+-} 0.0012, {Lambda}(D{sup 0} {yields} {pi}{sup -}{pi}{sup +})/{Lambda}(D{sup 0} {yields} K{sup -}{pi}{sup +}) = 0.03594 {+-} 0.00054 {+-} 0.00040, A{sub CP} (K{sup -}K{sup +}) = (2.0 {+-} 1.2 {+-} 0.6)%, and A{sub CP} ({pi}{sup -}{pi}{sup +}) = (1.0 {+-} 1.3 {+-} 0.6) %, where, in all cases, the first uncertainty is statistical and the second is systematic.
Date:
April 4, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
B physics: measurement of the lifetime difference between b_s mass eigenstates
We present measurements of the lifetimes and polarization amplitudes for B{sub s}{sup 0} {yields} J/{psi}{phi} and B{sub d}{sup 0} {yields} J/{psi} K*{sup 0} decays. Lifetimes of the heavy (H) and light (L) mass eigenstates in the B{sub s}{sup 0} system are separately measured for the first time by determining the relative contributions of amplitudes with definite CP as a function of the decay time.
Date:
April 28, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Top physics: measurement of the cross section for ttbar production in ppbar collisions using the kinematics of lepton + jets events
We present a measurement of the top pair production cross section in p{bar p} collisions at {radical}s = 1.96 TeV. We collect a data sample with an integrated luminosity of 194 {+-} 11 pb{sup -1} with the CDF II detector at the Fermilab Tevatron. We use an artificial neural network technique to discriminate between top pair production and background processes in a sample of 519 lepton+jets events, which have one isolated energetic charged lepton, large missing transverse energy and at least three energetic jets. We measure the top pair production cross section to be {sigma}{sub t{bar t}} = 6.6 {+-} 1.1 {+-} 1.5 pb, where the first uncertainty is statistical and the second is systematic.
Date:
April 27, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Top physics: measurement of the tt-bar production cross section in p anti-p collisions at s**(1/2) = 1.96 tev using lepton + jets events with secondary vertex b-tagging
We present a measurement of the t{bar t} production cross section using events with one charged lepton and jets from p{bar p} collisions at a center-of-mass energy of 1.96TeV. In these events, heavy flavor quarks from top quark decay are identified with a secondary vertex tagging algorithm. From 162 pb{sup -1} of data collected by the Collider Detector at Fermilab, a total of 48 candidate events are selected, where 13.5 {+-} 1.8 events are expected from background contributions. We measure a t{bar t} production cross section of 5.6{sub -1.1}{sup _1.2}(stat.){sub -0.6}{sup +0.9}(syst.)pb.
Date:
April 7, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Measurement of the cross section for t anti-t production in p anti-p collisions using the kinematics of lepton + jets events
The authors present a measurement of the top pair production cross section in p{bar p} collisions at {radical}s = 1.96 TeV. We collect a data sample with an integrated luminosity of 194 {+-} 11 pb{sup -1} with the CDF II detector at the Fermilab Tevatron. We use an artificial neural network technique to discriminate between top pair production and background processes in a sample of 519 lepton + jets events, which have one isolated energetic charged lepton, large missing transverse energy and at least three energetic jets. We measure the top pair production cross section to be {sigma}{sub t{bar t}} = 6.6 {+-} 1.1 {+-} 1.5 pb, where the first uncertainty is statistical and the second is systematic.
Date:
April 1, 2005
Creator:
Acosta, D.; Adelman, J.; Affolder, Anthony A.; Akimoto, T.; Albrow, M. G.; Ambrose, D. et al.
Object Type:
Article
System:
The UNT Digital Library
K0(s) and Lambda0 production studies in p anti-p collisions at s**(1/2) = 1800 and 630-GeV
The authors present a study of the production of K{sub s}{sup 0} and {Lambda}{sup 0} in inelastic p{bar p} collisions at {radical}s = 1800 and 630 GeV using data collected by the CDF experiment at the Fermilab Tevatron. Analyses of K{sub s}{sup 0} and {Lambda}{sup 0} multiplicity and transverse momentum distributions, as well as of the dependencies of the average number and (p{sub T}) of K{sub s}{sup 0} and {Lambda}{sup 0} on charged particle multiplicity are reported. Systematic comparisons are performed for the full sample of inelastic collisions, and for the low and high momentum transfer subsamples, at the two energies. The p{sub T} distributions extend above 8 GeV/c, showing a (p{sub T}) higher than previous measurements. The dependence of the mean K{sub s}{sup 0}({Lambda}{sup 0}) p{sub T} on the charged particle multiplicity for the three samples shows a behavior analogous to that of charged primary tracks.
Date:
April 1, 2005
Creator:
Acosta, D.; Affolder, Anthony A.; Albrow, M. G.; Ambrose, D.; Amidei, D.; Anikeev, K. et al.
Object Type:
Article
System:
The UNT Digital Library
Measurement of the azimuthal angle distribution of leptons from W boson decays as a function of the W transverse momentum in p anti-p collisions at s**(1/2) = 1.8-TeV
We present the first measurement of the A{sub 2} and A{sub 3} angular coefficients of the W boson produced in proton-antiproton collisions. We study W {yields} ev{sub e} and W {yields} {mu}{nu}{sub {mu}} candidate events produced in association with at least one jet at CDF, during Run Ia and Run Ib of the Tevatron at {radical}s = 1.8 TeV. The corresponding integrated luminosity was 110 pb{sup -1}. The jet balances the transverse momentum of the W and introduces QCD effects in W boson production. The extraction of the angular coefficients is achieved through the direct measurement of the azimuthal angle of the charged lepton in the Collins-Soper rest-frame of the W boson. The angular coefficients are measured as a function of the transverse momentum of the W boson. The electron, muon, and combined results are in good agreement with the Standard Model prediction, up to order {alpha}{sub s}{sup 2} in QCD.
Date:
April 1, 2005
Creator:
Acosta, D.; Affolder, Anthony A.; Albrow, M. G.; Ambrose, D.; Amidei, D.; Anikeev, K. et al.
Object Type:
Article
System:
The UNT Digital Library
Comments on the paper entitled "Determination of the equilibrium constant for complex formation in a binary mixture of chloroform and triethylamine from viscosity data on the basis of the ideal associated solution model"
Article commenting on the paper entitled "Determination of the equilibrium constant for complex formation in a binary mixture of chloroform and triethylamine from viscosity data on the basis of the idea associated solution model"
Date:
April 2000
Creator:
Acree, William E. (William Eugene)
Object Type:
Article
System:
The UNT Digital Library
Solubility of Crystalline Nonelectrolyte Solutes in Organic Solvents: Mathematical Correlation of Benzil Solubilities with the Abraham General Solvation Model
Article on the solubility of crystalline nonelectrolyte solutes in organic solvents and the mathematical correlation of benzil solubilities with the Abraham general solvation model.
Date:
April 1, 2002
Creator:
Acree, William E. (William Eugene) & Abraham, M. H. (Michael H.)
Object Type:
Article
System:
The UNT Digital Library
[Chrystalyn booth at Craft Mafia exhibition]
Photograph of a necklace display at Denton Craft Mafia's annual exhibition and sale at Art Six Coffee House. The necklaces, made of various shapes of beads, hang on metal racks and sit on a tabletop. A sheet of paper visible in the foreground reads, "Chrystalyn email list."
Date:
April 2006
Creator:
Adair, Nikki
Object Type:
Photograph
System:
The UNT Digital Library
[Necklaces on display at Craft Mafia exhibition]
Photograph of a necklace display at Denton Craft Mafia's annual exhibition and sale at Art Six Coffee House. The necklaces, made of square-shaped charms on ball chains, can be seen hanging in a row, receding into the background.
Date:
April 2006
Creator:
Adair, Nikki
Object Type:
Photograph
System:
The UNT Digital Library
[Wrist cuffs on display at Craft Mafia exhibition]
Photograph of a wrist cuff display at Denton Craft Mafia's annual exhibition and sale at Art Six Coffee House. The cuffs, made of floral and abstract patterned fabric, are being displayed on a wooden shelf.
Date:
April 2006
Creator:
Adair, Nikki
Object Type:
Photograph
System:
The UNT Digital Library
Demonstration of Key Elements of a Dual Phase Argon Detection System Suitable for Measurement of Coherent Neutrino-Nucleus Scattering
This feasibility study sought to demonstrate several necessary steps in a research program whose ultimate goal is to detect coherent scattering of reactor antineutrinos in dual-phase noble liquid detectors. By constructing and operating a Argon gas-phase drift and scintillation test-bed, the study confirmed important expectations about sensitivity of these detectors, and thereby met the goals set forth in our original proposal. This work has resulted in a successful Lab-Wide LDRD for design and deployment of a coherent scatter detector at a nuclear reactor, and strong interest by DOE Office of Science. In recent years, researchers at LLNL and elsewhere have converged on a design approach for a new generation of very low noise, low background particle detectors known as two-phase noble liquid/noble gas ionization detectors. This versatile class of detector can be used to detect coherent neutrino scattering-an as yet unmeasured prediction of the Standard Model of particle physics. Using the dual phase technology, our group would be the first to verify the existence of this process. Its (non)detection would (refute)validate central tenets of the Standard Model. The existence of this process is also important in astrophysics, where coherent neutrino scattering is assumed to play an important role in energy …
Date:
April 16, 2007
Creator:
Adam, B.; Celeste, W.; Christian, H.; Wolfgang, S. & Norman, M.
Object Type:
Report
System:
The UNT Digital Library