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Solubility of Pyrene in Ternary Propanol + Butanol + Cyclohexane Solvent Mixtures at 299.15 K (open access)

Solubility of Pyrene in Ternary Propanol + Butanol + Cyclohexane Solvent Mixtures at 299.15 K

Solubility of pyrene in ternary propanol + butanol + cyclohexane solvent mixtures at 299.15 K.
Date: July 12, 2001
Creator: Debase, Ebun M. & Acree, William E. (William Eugene)
System: The UNT Digital Library
Rate coefficients and mechanistic analysis for the reaction of hydroxyl radicals with 1,1-dichloroethylene and trans-1,2-dichloroethylene over an extended temperature range (open access)

Rate coefficients and mechanistic analysis for the reaction of hydroxyl radicals with 1,1-dichloroethylene and trans-1,2-dichloroethylene over an extended temperature range

Article on rate coefficients and mechanistic analysis for the reaction of hydroxyl radicals with 1,1-dichloroethylene and trans-1,2-dichloroethylene over an extended temperature range.
Date: July 17, 2001
Creator: Yamada, Takahiro; El-Sinawi, Abdulaziz; Siraj, Mohammad Masud, 1972-; Taylor, Philip H.; Peng, Jingping; Hu, Xiaohua et al.
System: The UNT Digital Library
Kinetic studies of the reaction of hydroxyl radicals with trichloroethylene and tetrachloroethylene (open access)

Kinetic studies of the reaction of hydroxyl radicals with trichloroethylene and tetrachloroethylene

Article on kinetic studies of the reaction of hydroxyl radicals with trichloroethylene and tetrachloroethylene.
Date: July 17, 2001
Creator: Tichenor, LeAnn B.; El-Sinawi, Abdulaziz; Yamada, Takahiro; Taylor, Philip H.; Peng, Jingping; Hu, Xiaohua et al.
System: The UNT Digital Library
Energy Absorption in Chopped Carbon Fiber Compression Molded Composites (open access)

Energy Absorption in Chopped Carbon Fiber Compression Molded Composites

In passenger vehicles the ability to absorb energy due to impact and be survivable for the occupant is called the ''crashworthiness'' of the structure. To identify and quantify the energy absorbing mechanisms in candidate automotive composite materials, test methodologies were developed for conducting progressive crush tests on composite plate specimens. The test method development and experimental set-up focused on isolating the damage modes associated with the frond formation that occurs in dynamic testing of composite tubes. Quasi-static progressive crush tests were performed on composite plates manufactured from chopped carbon fiber with an epoxy resin system using compression molding techniques. The carbon fiber was Toray T700 and the epoxy resin was YLA RS-35. The effect of various material and test parameters on energy absorption was evaluated by varying the following parameters during testing: fiber volume fraction, fiber length, fiber tow size, specimen width, profile radius, and profile constraint condition. It was demonstrated during testing that the use of a roller constraint directed the crushing process and the load deflection curves were similar to progressive crushing of tubes. Of all the parameters evaluated, the fiber length appeared to be the most critical material parameter, with shorter fibers having a higher specific energy …
Date: July 20, 2001
Creator: Starbuck, J. Michael; Jacob, George C. & Simunovic, Srdan
System: The UNT Digital Library
SYNCHROTRON X-RAY STUDY OF HYDRATION DYNAMICS IN THE SYNTHETIC SWELLING CLAY NA-FLUOROHECTORITE. (open access)

SYNCHROTRON X-RAY STUDY OF HYDRATION DYNAMICS IN THE SYNTHETIC SWELLING CLAY NA-FLUOROHECTORITE.

We present time-resolved synchrotron x-ray diffraction from the swelling clay Na fluorohectorite during controlled hydration and dehydration. A comparison of bulk and surface scattering reveals that the time dependence of basal Bragg peak positions and intensities has two components, which come into play at distinct temperatures. Intercalation of water into the crystal structure commences at a temperature of about 60 C on a time scale on the order of 1 hour. By contrast, percolation of water into the porous medium has a characteristic time constant of 3-4 h. This is the rate limiting process for hydration of the interior of the clay for T > 40 C. We suggest that the temperature-dependent percolation step may account for some of the hysteresis reported in earlier diffraction studies of the hydration of similar systems.
Date: July 22, 2001
Creator: DIMASI, E.; FOSSUM, J.O. & DASILVA, G.J.
System: The UNT Digital Library
Challenges to the Fermilab linac and booster accelerators (open access)

Challenges to the Fermilab linac and booster accelerators

A report on the challenges confronting the Fermilab Linac and Booster accelerators is presented. Plans to face those challenges are discussed. Historically, the Linac/Booster system has served only as an injector for the relatively low repetition rate Main Ring synchrotron. With construction of an 8 GeV target station for the 5 Hz MiniBooNE neutrino beam and requirements for rapid multi-batch injection into the Main Injector for the NUMI/MINOS experiment, the demand for 8 GeV protons will increase more than an order of magnitude above recent high levels. To meet this challenge, enhanced ion source performance, better Booster orbit control, a beam loss collimation/localization system, and improved diagnostics are among the items being pursued. Booster beam loss reduction and control are key to the entire near future Fermilab high energy physics program.
Date: July 12, 2001
Creator: Webber, Robert C.
System: The UNT Digital Library
Selecting the Design Entering Water Temperature for Vertical Geothermal Heat Pumps in Cooling-Dominated Applications (open access)

Selecting the Design Entering Water Temperature for Vertical Geothermal Heat Pumps in Cooling-Dominated Applications

At a military base in the Southeastern US, an energy services company (ESCO) has proposed to retrofit more than 1,000 family residences with geothermal heat pumps as part of an energy savings performance contract (ESPC). Each residence is to have one heat pump with its own ground heat exchanger consisting of two or more vertical bores. A design firm hired by the ESCO sized the heat pumps to meet peak cooling loads, and sized the borefields to limit the maximum entering water temperature (EWT) to the heat pumps to 95 F (35 C). Because there is some disagreement in the geothermal heat pump industry over the peak temperature to be used for design (some designers and design manuals recommend temperatures as low as 85 F [29 C], while equipment manufacturers and others specify temperatures of 100 F [38 C] or higher) the authors were requested to examine the designs in detail to determine whether the 95 F (35 C) limit was adequate to ensure occupant comfort, efficient operation, and low capital and operating costs. It was found that three of the designer's assumptions made the borefield designs more conservative (i.e., longer) than the 95 F (35 C) limit would indicate. …
Date: July 12, 2001
Creator: Shonder, J. A.
System: The UNT Digital Library
AN INVESTIGATION OF SHOCK-ACCELERATED, UNSTABLE GAS CYLINDERS USING SIMULTANEOUS DENSITY-FIELD VISUALIZATION AND PIV (open access)

AN INVESTIGATION OF SHOCK-ACCELERATED, UNSTABLE GAS CYLINDERS USING SIMULTANEOUS DENSITY-FIELD VISUALIZATION AND PIV

None
Date: July 1, 2001
Creator: TOMKINS, C. D.; PRESTRIDGE, K. P. & AL, ET
System: The UNT Digital Library
A search for coupled-bunch instability in the Fermilab Main Injector (open access)

A search for coupled-bunch instability in the Fermilab Main Injector

In the Fermilab Main Injector (MI) we are planning to double the bunch intensity from its design value by slip stacking. The accelerator consists of 18 rf cavities which operate at a harmonic number of 588. These cavities are known to have many higher ordered resonances. Longitudinal coupled-bunch instability induced by excitation of the rf cavities may be an important issue to be addressed in the intensity upgrade. Here we have carried out some simulation studies of the longitudinal coupled bunch instability to investigate bunch intensity limits. The results are presented in this paper.
Date: July 3, 2001
Creator: al., C. M. Bhat et
System: The UNT Digital Library
Equations for Gas Releasing Process From Pressurized Vessels in Odh Evaluation. (open access)

Equations for Gas Releasing Process From Pressurized Vessels in Odh Evaluation.

IN THE EVALUATION OF ODH, THE CALCULATION OF THE SPILL RATE FROM THE PRESSURIZED VESSEL IS THE CENTRAL TASK. THE ACCURACY OF THE ENGINEERING ESTIMATION BECOMES ONE OF THE SAFETY DESIGN ISSUES. THIS PAPER SUMMARIZES THE EQUATIONS FOR THE OXYGEN CONCENTRATION CALCULATION IN DIFFERENT CASES, AND DISCUSSES THE EQUATIONS FOR THE GAS RELEASE PROCESS CALCULATION BOTH FOR THE HIGH-PRESSURE GAS TANK AND THE LOW-TEMPERATURE LIQUID CONTAINER.
Date: July 16, 2001
Creator: Jia, L. X. & Wang, L.
System: The UNT Digital Library
A laser strain gauge for accelerator targets. (open access)

A laser strain gauge for accelerator targets.

Multi megawatt accelerators can deliver sufficient power to a target to destroy it in a few pulses. In order to look at the response of solid and liquid targets under these high power pulses, we are developing optical methods of measuring surface deformations with time resolutions limited by laser pulse lengths. These methods can be used to examine the surfaces of solids and liquids during elastic deformation and unstable hydrodynamic flows. We present preliminary results of a system designed for target tests using the Brookhaven AGS and the Argonne CHM linac.
Date: July 17, 2001
Creator: Hassanein, A. & Norem, J.
System: The UNT Digital Library
Space-charge effects on bunch rotation in the longitudinal phase space (open access)

Space-charge effects on bunch rotation in the longitudinal phase space

The longitudinal and transverse space-charge effects on bunch rotation in the longitudinal phase space designed to produce an intense short proton bunch are discussed. A criterion for length broadening due to space-charge modification of the rf potential is given. As for the transverse effect, the incoherent space-charge tune shifts will affect the bunch rotation unless the chromaticities are properly corrected.
Date: July 3, 2001
Creator: Ng, King-Yuen
System: The UNT Digital Library
SERPENTINITES USED FOR CARBON DIOXIDE SEQUESTRATION: A POSSIBLE ECONOMIC SOURCE FOR PGE (open access)

SERPENTINITES USED FOR CARBON DIOXIDE SEQUESTRATION: A POSSIBLE ECONOMIC SOURCE FOR PGE

None
Date: July 1, 2001
Creator: PORTER, K. A.
System: The UNT Digital Library
Ultrathin diamond-like carbon films deposited by filtered carbon vacuum arcs (open access)

Ultrathin diamond-like carbon films deposited by filtered carbon vacuum arcs

Ultrathin (< 5 nm) hard carbon films are of great interest to the magnetic storage industry as the areal density approaches 100 Gbit/in{sup 2}. These films are used as overcoats to protect the magnetic layers on disk media and the active elements of the read-write slider. Tetrahedral amorphous carbon films can be produced by filtered cathodic arc deposition, but the films will only be accepted by the storage industry only if the ''macroparticle'' issue has been solved. Better plasma filters have been developed over recent years. Emphasis is put on the promising twist filter system - a compact, open structure that operates with pulsed arcs and high magnetic field. Based on corrosion tests it is shown that the macroparticle reduction by the twist filter is satisfactory for this demanding application, while plasma throughput is very high. Ultrathin hard carbon films have been synthesized using S-filter and twist filter systems. Film properties such as hardness, elastic modulus, wear, and corrosion resistance have been tested.
Date: July 13, 2001
Creator: Anders, Andre; Fong, Walton; Kulkarni, Ashok; Ryan, Francis W. & Bhatia, C. Singh
System: The UNT Digital Library
LOW TEMPERATURE ELASTIC CONSTANTS AND NONLINEAR ACOUSTIC RESPONSE IN ROCKS AND COMPLEX MATERIALS (open access)

LOW TEMPERATURE ELASTIC CONSTANTS AND NONLINEAR ACOUSTIC RESPONSE IN ROCKS AND COMPLEX MATERIALS

None
Date: July 1, 2001
Creator: DARLING, T. W.; JOHNSON, P. A. & AL, ET
System: The UNT Digital Library
Analytical study and tracking simulations of the beam-beam compensation at Tevatron (open access)

Analytical study and tracking simulations of the beam-beam compensation at Tevatron

Head-on and long-range induced tunespread of about 0.025 in the Tevatron collider at Run II (together with the increased strength of the resonances) can significantly deteriorate the {bar p} lifetime and the collider luminosity. It was proposed to employ the so-called Tevatron Electron Lenses (TEL) to compress the beam-beam footprint and eliminate completely the bunch-to-bunch tunespread (PACMAN effect) for small amplitude particles. The first lens has been recently installed and tested [1]. This report presents results of analytical studies and tracking simulations of the linear beam-beam compensation (elimination of the bunch-to-bunch tune variation). Compression of the beam-beam footprint (nonlinear compensation) is discussed in [2].
Date: July 2, 2001
Creator: Shatilov, Dmitry; Alexahin, Yuri & Shiltsev, Vladimir
System: The UNT Digital Library
Measurement of small radius gradient magnets using ion beams (open access)

Measurement of small radius gradient magnets using ion beams

Several small and precise 90{degree}, 20-inch-radius bending and focusing magnet systems will be needed for the transport line of the Fermilab Electron Cooling Project to transport 4.36 MeV electrons. Originally, it was anticipated that these magnets would have a gradient index of {minus}1/2. To measure these magnets and complete achromatic bend modules, a well defined beam transport system was developed to determine the transfer matrix knowing the position and angle of several input and output beam rays passing through the magnet. The beam for this was a 12.5 keV proton beam that has the same magnetic rigidity as the electron beam in the final setup. The magnetic field is approximately 300 Gauss. For this purpose a high-brightness proton source was used and the beam collimated to give a low emittance ({approximately}10{sup {minus}8} m rad) pencil beam of {approximately}1 mm diameter with a current of {approximately}100 nA. Details of the system and results of measuring a magnet will be presented.
Date: July 16, 2001
Creator: al., Charles W. Schmidt et
System: The UNT Digital Library
Heavy flavor physics at CDF II (open access)

Heavy flavor physics at CDF II

Tevatron experiments will soon begin Run II data taking with an aggressive B physics program. The B physics reach of the CDF and D0 experiments already seems competitive and complementary to that of B factories. We report on the future plans for B physics and CP violation measurements at the Tevatron.
Date: July 12, 2001
Creator: Cerri, A.
System: The UNT Digital Library
Developing a Standard Method of Test for Packaged, Solid-Desiccant Based Dehumidification Systems (open access)

Developing a Standard Method of Test for Packaged, Solid-Desiccant Based Dehumidification Systems

A draft Method of Test (MOT) has been proposed for packaged, air-to-air, desiccant-based dehumidifier systems that incorporate a thermally-regenerated desiccant material for dehumidification. This MOT is intended to function as the ''system'' testing and rating compliment to the desiccant ''component'' (desiccant wheels and/or cassettes) MOT (ASHRAE 1998) and rating standard (ARI 1998) already adopted by industry. This draft standard applies to ''packaged systems'' that: Use desiccants for dehumidification of conditioned air for buildings; Use heated air for regeneration of the desiccant material; Include fans for moving process and regeneration air; May include other system components for filtering, pre-cooling, post-cooling, or heating conditioned air; and May include other components for humidification of conditioned air. The proposed draft applies to four different system operating modes depending on whether outdoor or indoor air is used for process air and regeneration air streams . Only the ''ventilation'' mode which uses outdoor air for both process and regeneration inlets is evaluated in this paper. Performance of the dehumidification system is presented in terms that would be most familiar and useful to designers of building HVAC systems to facilitate integration of desiccant equipment with more conventional hardware. Parametric performance results from a modified, commercial desiccant dehumidifier …
Date: July 12, 2001
Creator: Sand, J.R.
System: The UNT Digital Library
EFFICIENT FEATURE-BASED CONTOUR EXTRACTION (open access)

EFFICIENT FEATURE-BASED CONTOUR EXTRACTION

None
Date: July 1, 2001
Creator: GATTIKER, J. R.
System: The UNT Digital Library
Space charge and beam stability of the proposed Fermilab proton driver in Phase I (open access)

Space charge and beam stability of the proposed Fermilab proton driver in Phase I

Issues concerning beam stability of the proposed Fermi-lab proton driver are studied in its Phase I. Although the betatron tune shifts are dominated by space charge, these shifts are less than 0.25 and will therefore not drive the symmetric and antisymmetric modes of the beam envelope into instability. The longitudinal space-charge force is large and inductive inserts may be needed to compensate for the distortion of the rf potential. Although the longitudinal impedance is space-charge dominated, it will not drive any microwave instability, unless the real part of the impedance coming from the inductive inserts and wall resistivity of the beam tube are large enough. The design of the beam tube is therefore very important in order to limit the flow of eddy current and keep wall resistivity low. The transverse impedance is also space-charge dominated. With the proton driver operated at an imaginary transition gamma, however, Landau damping will never be canceled and beam stability can be maintained with negative chromaticities.
Date: July 20, 2001
Creator: Zotter, K. Y. Ng and B.
System: The UNT Digital Library
Molybdenum Disilicide Composites for Glass Processing Sensors (open access)

Molybdenum Disilicide Composites for Glass Processing Sensors

None
Date: July 1, 2001
Creator: Petrovic, J. J.; Castro, R. G. & Al, Et
System: The UNT Digital Library
Experimental demonstration of two beam acceleration using dielectric step-up transformer. (open access)

Experimental demonstration of two beam acceleration using dielectric step-up transformer.

We report on the experimental results of the dielectric based two beam accelerator (step-up transformer). By using a single high charge beam, we have generated and extracted a high power RF pulse from a 7.8 GHz primary dielectric structure and then subsequently transferred to a second accelerating structure with higher dielectric constant and smaller transverse dimensions. We have measured the energy change of a second (witness) beam passing through the acceleration stage. The measured gradient is > 4 times the deceleration gradient. The detailed experiment of set-up and results of the measurements are discussed. Future plans for the development of a 100 MeV demonstration accelerator based on this technique is presented.
Date: July 17, 2001
Creator: Gai, W.; Conde, M. E.; Konecny, R.; Power, J. G.; Schoessow, P.; Simpson, J. et al.
System: The UNT Digital Library
An e{sup +}e{sup -} collider in the VLHC tunnel. (open access)

An e{sup +}e{sup -} collider in the VLHC tunnel.

None
Date: July 17, 2001
Creator: Barcikowski, A.; Goeppner, G.; Norem, J.; Rotela, E.; Rusthoven, B.; Sharma, S. et al.
System: The UNT Digital Library