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Air Pollutant Penetration Through Airflow Leaks Into Buildings

Description: The penetration of ambient air pollutants into the indoor environment is of concern owing to several factors: (1) epidemiological studies have shown a strong association between ambient fine particulate pollution and elevated risk of human mortality; (2) people spend most of their time in indoor environments; and (3) most information about air pollutant concentration is only available from ambient routine monitoring networks. A good understanding of ambient air pollutant transport from source t… more
Date: September 1, 2002
Creator: Liu, De-Ling
Partner: UNT Libraries Government Documents Department
open access

Analysis and Development of FACE Automatic Apparatus for Rapid Identification of Transuranium Isotopes

Description: A description of and operating manual for the FACE Automatic Apparatus has been written along with a documentation of the FACE machine operating program, to provide a user manual for the FACE Automatic Apparatus. In addition, FACE machine performance was investigated to improve transuranium throughput. Analysis of the causes of transuranium isotope loss was undertaken both chemical and radioactive. To lower radioactive loss, the dynamics of the most time consuming step of the FACE machine, the … more
Date: September 1, 1978
Creator: Sebesta, E.H.
Partner: UNT Libraries Government Documents Department
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Analysis of Bs flavor oscillations at CDF

Description: The search for and study of flavor oscillations in the neutral B{sub s}B{sub s} meson system is an experimentally challenging task. It constitutes a flagship analysis of the Tevatron physics program. In this dissertation, they develop an analysis of the time-dependent B{sub s} flavor oscillations using data collected with the CDF detector. The data samples are formed of both fully and partially reconstructed B meson decays: B{sub s} {yields} D{sub s}{pi}({pi}{pi}) and B{sub s} {yields} D{sub s}… more
Date: September 1, 2006
Creator: Leonardo, Nuno T.
Partner: UNT Libraries Government Documents Department
open access

Analysis of in-situ rock joint strength using digital borehole scanner images

Description: The availability of high resolution digital images of borehole walls using the Borehole Scanner System has made it possible to develop new methods of in-situ rock characterization. This thesis addresses particularly new approaches to the characterization of in-situ joint strength arising from surface roughness. An image processing technique is used to extract the roughness profile from joints in the unrolled image of the borehole wall. A method for estimating in-situ Rengers envelopes using thi… more
Date: September 1, 1994
Creator: Thapa, B. B.
Partner: UNT Libraries Government Documents Department
open access

Analysis of the application of decontamination technologies to radioactive metal waste minimization using expert systems

Description: Radioactive metal waste makes up a significant portion of the waste currently being sent for disposal. Recovery of this metal as a valuable resource is possible through the use of decontamination technologies. Through the development and use of expert systems a comparison can be made of laser decontamination, a technology currently under development at Ames Laboratory, with currently available decontamination technologies for applicability to the types of metal waste being generated and the eff… more
Date: September 30, 1993
Creator: Bayrakal, S.
Partner: UNT Libraries Government Documents Department
open access

Anisotropy in CdSe quantum rods

Description: The size-dependent optical and electronic properties of semiconductor nanocrystals have drawn much attention in the past decade, and have been very well understood for spherical ones. The advent of the synthetic methods to make rod-like CdSe nanocrystals with wurtzite structure has offered us a new opportunity to study their properties as functions of their shape. This dissertation includes three main parts: synthesis of CdSe nanorods with tightly controlled widths and lengths, their optical an… more
Date: September 1, 2003
Creator: Li, Liang-shi
Partner: UNT Libraries Government Documents Department
open access

Anomalous loss of DT alpha particles in the Tokamak Fusion Test Reactor

Description: An escaping alpha collector probe has been developed for TFTR`s DT phase. Energy distributions of escaping alphas have been determined by measuring the range of {alpha}-particles implanted into nickel foils located within the alpha collector. Results at 1.0 MA of plasma current are in good agreement with predictions for first orbit alpha loss. Results at 1.8 MA, however, show a significant anomalous loss of partially thermalized alphas (in addition to the expected first orbit loss), which is no… more
Date: September 1, 1997
Creator: Herrmann, H.W.
Partner: UNT Libraries Government Documents Department
open access

t anti-t production cross section measurement using soft electron tagging in p anti-p collisions at s**(1/2) = 1.96-TeV

Description: We measure the production cross section of t{bar t} events in p{bar p} collisions at {radical}s = 1.96 TeV. The data was collected by the CDF experiment in Run 2 of the Tevatron accelerator at the Fermi National Accelerator Laboratory between 2002 and 2007. 1.7 fb{sup -1} of data was recorded during this time period. We reconstruct t{bar t} events in the lepton+jets channel, whereby one W boson - resulting from the decay of the top quark pairs - decays leptonically and the other hadronically. T… more
Date: September 1, 2008
Creator: Chou, John Paul & U., /Harvard
Partner: UNT Libraries Government Documents Department
open access

Application of an Electrochemical Quartz Crystal Microbalance to the study of electrocatalytic films

Description: The EQCM was used to study the deposition and composition of electrodeposited pure PbO{sub 2} and Bi-doped PbO{sub 2} active toward anodic oxygen-transfer reactions. Within the doped films, Bi is incorporated as Bi{sup +5} in the form of BiO{sub 2}A, where A is ClO{sub 4}{sup {minus}} or NO{sub 3}{sup {minus}}. For deposition of these 2 materials, changes in hydration between the Au oxide and the depositing film resulted in higher mass-to-charge ratios. XRD and XPS were used to study the films;… more
Date: September 1, 1993
Creator: Gordon, J. S., Jr.
Partner: UNT Libraries Government Documents Department
open access

Application of generalized classical trajectories in nuclear physics

Description: A new semi-classical method, the so-called uniform semiclassical approximation, is described briefly and then applied to two nuclear physics problems. The basic features of this method are that the dynamics of the problem is treated completely classically (that is, one solves classical equations of motion), but the quantum mechanical superposition principle is retained by evaluating a phase along the classical trajectory and adding probability amplitudes for indistinguishable processes rather t… more
Date: September 1, 1975
Creator: Leser, H.M.
Partner: UNT Libraries Government Documents Department
open access

Applications of highly spin-polarized xenon in NMR

Description: The main goal of the work presented in this thesis is produce highly spin-polarized xenon to create much greater signal intensities (up to 54,000 times greater) so as to allow studies to be made on systems with low surface area and long spin-lattice relaxation times. The spin-exchange optical pumping technique used to create high nuclear spin polarization is described in detail in chapter two. This technique is initially applied to some multiple-pulse optically detected NMR experiments in low m… more
Date: September 1, 1993
Creator: Long, H. W.
Partner: UNT Libraries Government Documents Department
open access

Atmospheric neutrino observations in the MINOS far detector

Description: This thesis presents the results of atmospheric neutrino observations from a 12.23 ktyr exposure of the 5.42 kt MINOS Far Detector between 1st August 2003 until 1st March 2006. The separation of atmospheric neutrino events from the large background of cosmic muon events is discussed. A total of 277 candidate contained vertex {nu}/{bar {nu}}{sub {mu}} CC data events are observed, with an expectation of 354.4{+-}47.4 events in the absence of neutrino oscillations. A total of 182 events have clear… more
Date: September 1, 2007
Creator: Chapman, John Derek & U., /Cambridge
Partner: UNT Libraries Government Documents Department
open access

B Flavor Tagging Calibration and Search for B(s) Oscillations in Semileptonic Decays with the CDF Detector at Fermilab

Description: In this thesis we present a search for oscillations of B{sub s}{sup 0} mesons using semileptonic B{sub s}{sup 0} {yields} D{sub s}{sup -}{ell}{sup +}{nu} decays. Data were collected with the upgraded Collider Detector at Fermilab (CDFII) from events produced in collisions of 980 GeV protons and antiprotons accelerated in the Tevatron ring. The total proton-antiproton center-of-mass energy is 1.96 TeV. The Tevatron is the unique source in the world for B{sub s}{sup 0} mesons, to be joined by the… more
Date: September 1, 2005
Creator: Giurgiu, Gavril A.
Partner: UNT Libraries Government Documents Department
open access

Band anticrossing effects in highly mismatched semiconductor alloys

Description: The first five chapters of this thesis focus on studies of band anticrossing (BAC) effects in highly electronegativity- mismatched semiconductor alloys. The concept of bandgap bowing has been used to describe the deviation of the alloy bandgap from a linear interpolation. Bowing parameters as large as 2.5 eV (for ZnSTe) and close to zero (for AlGaAs and ZnSSe) have been observed experimentally. Recent advances in thin film deposition techniques have allowed the growth of semiconductor alloys co… more
Date: September 9, 2002
Creator: Wu, Junqiao
Partner: UNT Libraries Government Documents Department
open access

Beam Diagnosis and Lattice Modeling of the Fermilab Booster

Description: A realistic lattice model is a fundamental basis for the operation of a synchrotron. In this study various beam-based measurements, including orbit response matrix (ORM) and BPM turn-by-turn data are used to verify and calibrate the lattice model of the Fermilab Booster. In the ORM study, despite the strong correlation between the gradient parameters of adjacent magnets which prevents a full determination of the model parameters, an equivalent lattice model is obtained by imposing appropriate c… more
Date: September 1, 2005
Creator: Huang, Xiaobiao
Partner: UNT Libraries Government Documents Department
open access

Beam Dynamics in a Muon Ionisation Cooling Channel

Description: The Neutrino Factory has been proposed as a facility to provide an intense source of neutrinos suitable for the measurement of neutrino oscillation parameters and a possible CP violating phase to unprecedented precision. In the Neutrino Factory, neutrinos are produced by the decay of a muon beam with 20-50 GeV per muon. Initially, the muon beam occupies a large volume in phase space, which must be reduced before the beam can be accelerated. The proposed method to achieve this is to use a soleno… more
Date: September 1, 2008
Creator: Rogers, Chris
Partner: UNT Libraries Government Documents Department
open access

Bond and Low Cycle Fatigue Behavior of Thermoset Composite Reinforcing for the Concrete Industry

Description: This thesis encompasses two separate research projects. The first project, described in Chapter 2 was a project investigating the fatigue behavior of thermoset Fiber Composite (FC) sandwich wall ties. The second research project detailed in this thesis was a project studying the bond and tensile properties of FC rod and FC fibers.
Date: September 21, 1990
Creator: Barnes, Bruce
Partner: UNT Libraries Government Documents Department
open access

Carbon doping of III-V compound semiconductors

Description: Focus of the study is C acceptor doping of GaAs, since C diffusion coefficient is at least one order of magnitude lower than that of other common p-type dopants in GaAs. C ion implantation results in a concentration of free holes in the valence band < 10% of that of the implanted C atoms for doses > 10{sup 14}/cm{sup 2}. Rutherford backscattering, electrical measurements, Raman spectroscopy, and Fourier transform infrared spectroscopy were amonth the techniques used. Ga co-implantation increase… more
Date: September 1, 1994
Creator: Moll, A. J.
Partner: UNT Libraries Government Documents Department
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