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Regenerator-design study and its application to turbine-propeller engines

Description: Report presenting a comprehensive study of regeneration as a means of improving the load-range performance of turbine-propeller aircraft. Comparisons occurred across a variety of combustion temperatures, regenerator warming effectivenesses, altitudes, flight speeds, and flight distances. Results regarding cycle analysis, ideal gains from regeneration, and actual gains from regeneration are provided.
Date: January 1951
Creator: Manson, S. V.
Partner: UNT Libraries Government Documents Department

Experiments on Cold-Trap Regeneration by NaH Decomposition

Description: Cold-trap regeneration may be very important in future LMFBRs because of the expected high hydrogen source from the steam generators. This hydrogen precipitates as NaH in the cold trap and may fill the trap within one year of operation. Several methods of cold-trap regeneration were considered, but the simplest and least expensive appears to be decomposition of NaH under vacuum at elevated temperatures. Experiments were done to assess the feasibility of this method for cold-trap regeneration. Small-scale simulated cold traps (SCT) were loaded with NaH and NaH plus Na2O, and were heated both under vacuum and under a sweep gas at 100 kPa. The evolved hydrogen was converted to water by a CuO bed and collected in a weighing tube.
Date: June 1980
Creator: Argonne National Laboratory. Chemical Engineering Division.
Partner: UNT Libraries Government Documents Department

Enrichment of By-Product Materials from Steel Pickling Acid Regeneration Plants (TRP 9942)

Description: A new process for manufacturing an enriched, iron-based product (strontium hexaferrite) in existing steel pickling acid regeneration facilities was evaluated. Process enhancements and equipment additions were made to an existing acid regeneration plant to develop and demonstrate (via pilot scale testing and partial-capacity production trials) the viability of a patented method to produce strontium-based compounds that, when mixed with steel pickling acid and roasted, would result in a strontium hexaferrite powder precursor which could then be subjected to further heat treatment in an atmosphere that promotes rapid, relatively low-temperature formation of discrete strontium hexaferrite magnetic domains yielding an enriched iron-based product, strontium hexaferrite, that can be used in manufacturing hard ferrite magnets.
Date: September 30, 2009
Creator: Lu Swan, Delta Ferrites LLC
Partner: UNT Libraries Government Documents Department

J/psi Production in Quark-Gluon Plasma

Description: We study J/{psi} production at RHIC and LHC energies with both initial production and regeneration. We solve the coupled set of transport equation for the J/{psi} distribution in phase space and the hydrodynamic equation for evolution of quark-gluon plasma. At RHIC, continuous regeneration is crucial for the J/{psi} momentum distribution while the elliptic flow is still dominated by initial production. At LHC energy, almost all the initially created J/{psi}s are dissociated in the medium and regeneration dominates the J/{psi} properties.
Date: October 30, 2006
Creator: Yan, Li; Zhuang, Pengfei & Xu, Nu
Partner: UNT Libraries Government Documents Department

Adsorption and Ultrasound-Assisted Sorbent Regeneration

Description: This work was conducted for the department of Energy. In this work, we developed a class of new sorbents that were highly sulfur selective and had high sulfur capacities. The study consisted of two sections. Development of the new sorbents is described in Section 1, and Section was a fundamental study, conducted for a better understanding for desulfurization of jet fuels. More details of the results are given blow separately for the two sections.
Date: September 30, 2006
Creator: Wang, Yuhe; Ma, Liping & Yang, Ralph T.
Partner: UNT Libraries Government Documents Department

INVESTIGATION ON DURABILITY AND REACTIVITY OF PROMISING METAL OXIDE SORBENTS DURING SULFIDATION AND REGENERATION

Description: The main objective of this research project during this quarter is to investigate effects of hydrogen on initial absorption as well as equilibrium absorption of 2500-ppm H2S into 0.1-g TU-188 sorbent in the presence of 10 vol % moisture at the 0.12-s space time and 530 o C.
Date: August 1, 1998
Creator: Kwon, K. C.
Partner: UNT Libraries Government Documents Department

INVESTIGATION ON DURABILITY AND REACTIVITY OF PROMISING METAL OXIDE SORBENTS DURING SULFIDATION AND REGENERATION

Description: The main objectives of this research project during this quarter are to investigate effects of hydrogen, moisture, concentrations of H<sub>2</sub> S, and residence time of reaction gas mixtures on equilibrium absorption as well as dynamic absorption of H<sub>2</sub> S into the TU-188 sorbent at 530 o C, and to evaluate effective diffusivity of H<sub>2</sub> S through the sorbent particles, using the newly-fabricated differential reactor.
Date: December 1, 1997
Creator: KWON, K.C.
Partner: UNT Libraries Government Documents Department

The photosynthetic response of the perennial ryegrass (Lolium perenne) in its fifth year of free-air CO(sub 2) enrichment (FACE) at Eschikon, Switzerland

Description: Stands of Ryegrass (Lolium perenne L. cv.Bastion) were grown in the field at ambient or elevated (600 {micro}mol mol{sup {minus}1}) [CO{sub 2}], high (560 kg Ha{sup {minus}1} y{sup {minus}1}) or low (140 kg Ha{sup {minus}1} y{sup {minus}1}) nitrogen addition and were harvested five times a year during the growing season. The plants were sown during 1992, additional plots being sown during 1995. These were in their fifth year and second year of growth respectively. Exposure to elevated [CO{sub 2}] was carried out with a Free-Air CO{sub 2} Enrichment (FACE) system which provides the most realistic system of fumigation currently available. Elevated [CO{sub 2}] increased diurnal CO{sub 2} uptake by between 40 to 83% while reducing stomatal conductance by between 1 and 38% in all of the 1992 grown plants measured at high [CO{sub 2}]. Analysis of the A/c{sub i} response of 1992 grown plants showed no acclimation of the photosynthetic apparatus in response to elevated [CO{sub 2}] - both V{sub c,max} (a measure of the maximum in vivo rate of carboxylation) and J{sub max} (a measure of the maximum capacity for the regeneration of RuBP) showed no significant change during any of the periods of regrowth. In contrast the leaves of 1995 grown plants, appeared to be experiencing an acclimatory change in their photosynthetic apparatus in response to elevated [CO{sub 2}]. However, this negative response seemed to be removed directly after a harvest when the source:sink balance had increased. The apparent lack of an acclimatory response after almost 5 years of growth at elevated [CO{sub 2}], suggests that L. perenne may be close to achieving the appropriate photosynthetic adjustments which would allow it to attain a significantly higher photosynthetic potential.
Date: 1999-01~
Creator: Anderson, J. P.; Long, S. P. & Williams, J.
Partner: UNT Libraries Government Documents Department

Neural Grafting: Repairing the Brain and Spinal Cord

Description: This special report, the second of our neuroscience series, discusses the field of neural grafting into the brain and spinal cord to treat neurological disorders. It describes the technology of neural grafting, the neurological conditions that it may be used to treat, and the patient populations that are affected. Also, the legal and ethical issues raised by the development of neural grafting techniques are discussed. The report includes a range of options for congressional action related to the Federal funding of transplantation research using human fetal tissue, the adequacy of existing Federal laws and regulations regarding the use of human fetal tissue, and the role of the Federal Government in guiding the development and promoting the safety and efficacy of neural grafting procedures.
Date: October 1990
Creator: United States. Congress. Office of Technology Assessment.
Partner: UNT Libraries Government Documents Department

CUB DI (Deionization) column control system

Description: For the old MR (Main Ring), deionization was done with two columns in CUB, using an ion exchange process. Typically 65 GPM of LCW flew through a column, and the resistivity was raised from 3 Mohm-cm to over 12 Mohm-cm. After a few weeks, columns lost their effectiveness and had to be regenerated in a process involving backwashing and adding hydrochloric acid and sodium hydroxide. For normal MR operations, LCW returned from the ring and passed through the two columns in parallel for deionization, although the system could have been operated satisfactorily with only one in use. A 3000 gallon reservoir (the Spheres) provided a reserve of LCW for allowing water leaks and expansions in the MR. During the MI (Main Injector) construction period, the third DI column was added to satisfy requirements for the MI. When the third column was added, the old regeneration controller was replaced with a new controller based on an Allen-Bradley PLC (i.e., SLC-5/04). The PLC is widely used and well documented, and therefore it may allow us to modify the regeneration programs in the future. In addition to the above regeneration controller, the old control panels (which were used to manipulate pumps and valves to supply LCW in Normal mode and to do Int. Recir. (Internal Recirculation) and Makeup) were replaced with a new control system based on Sixtrak Gateway and I/O modules. For simplicity, the new regeneration controller is called as the US Filter system, and the new control system is called as the Fermilab system in this writing.
Date: July 2, 1999
Creator: Seino, K. C.
Partner: UNT Libraries Government Documents Department

Measurement of Local Frequencies of Filter Regeneration and their Effect on Successive Operating Cycles

Description: Stable operation, characterized by a succession of uniform filtration cycles with acceptable duration and pressure increase, remains a key issue in high temperature gas filtration. Ceramic filters are known to sometimes become instable. This is somehow related to ''patchy cleaning'', but cause-and-effect relationships have been difficult to identify. The objective of this contribution is to investigate incomplete regeneration patterns in detail, to try to classify them, and to identify relationships between the residual cake patterns and the form of successive filtration cycles. The work comprises both modeling and experiments at room temperature and high temperature conditions on ceramic media using quartz dust and bark ash.
Date: September 19, 2002
Creator: Dittler, A. & Kasper, G.
Partner: UNT Libraries Government Documents Department

Sorption of Cesium From Aqueous Waste Solution on SuperLig 644 Resin

Description: The removal of cesium from aqueous waste solution was investigated in a column setup using SuperLig(R) 644 resin. The resin was significantly coarser in size than those used in previous studies because of hydraulic problems encountered during pilot-scale tests. The bed volume (BV = 140) at the onset of breakthrough surpassed the design requirement of 100 BV at 50 percent breakthrough. The percent of cesium removed by the resin at the onset of breakthrough was 99.96. The elution of cesium with 0.5 M HNO3 was satisfactory with a peak BV of 2.5. The elution BV for C/Co = 0.01 was 10, which is less than the target of 15 BV. The percent of sorbed cesium eluted from the resin was 99.88 percent. In addition, the BV of the various solutions used for the supporting process steps (feed displacement, post-feed displacement rinse, post-elution rinse, and regeneration) of the cesium ion exchange system was sufficient.
Date: August 24, 2004
Creator: ADU-WUSU, KOFI
Partner: UNT Libraries Government Documents Department

LAB STUDY ON REGENERATION OF SPENT DOWEX 21K 16-20 MESH ION EXCHANGE RESIN

Description: Currently the effort to remove chromate from groundwater in the 100K and 100H Areas uses DOWEX 21K 16-20. This report addresses the procedure and results of a laboratory study for regeneration of the spent resin by sodium hydroxide, sulfuric acid, or sodium sulfate to determine if onsite regeneration by the Effluent Treatment Facility is a feasible option.
Date: January 24, 2007
Creator: DUNCAN, J.B.
Partner: UNT Libraries Government Documents Department

Suppression of ICE and Apoptosis in Mammary Epithelial Cells by Extracellular Matrix

Description: Apoptosis (programmed cell death) plays a major role in development and tissue regeneration. Basement membrane extracellular matrix (ECM), but not fibronectin or collagen, was shown to suppress apoptosis of mammary epithelial cells in tissue culture and in vivo. Apoptosis was induced by antibodies to beta 1 integrins or by overexpression of stromelysin-1, which degrades ECM. Expression of interleukin-1 beta converting enzyme (ICE) correlated with the loss of ECM, and inhibitors of ICE activity prevented apoptosis. These results suggest that ECM regulates apoptosis in mammary epithelial cells through an integrin-dependent negative regulation of ICE expression.
Date: December 1, 1994
Creator: Boudreau, Nancy; Sympson, C. J.; Werb, Zena & Bissell, Mina J.
Partner: UNT Libraries Government Documents Department

A measurement of the regeneration parameter in the 100 GeV/C range

Description: We propose a wire chamber experiment to measure the coherent regenerator parameter {rho} in hydrogen in the 60 to 120 GeV/c range. In this report we show that, by using the neutral beam at NAL and currently existing apparatus, {rho} can be measured in the momentum range from 90 to 110 GeV/c to a precision of {approx} {+-}5 x 10{sup -4} and its phase to {approx} {+-} 8 degrees. This results in an uncertainty in {Delta}{sigma} = {sigma}({bar K}{sup 0}p) - ({sigma}K{sup 0}p) of {approx} {+-}0.10mb.
Date: July 1, 1970
Creator: Buchanan, C.D.; Drickey, Darrell James; Rudnick, F.C.; Shepard, P.F.; Stork, D.H.; Ticho, H.K. et al.
Partner: UNT Libraries Government Documents Department

Coherent rho 0 photoproduction in bulk matter at high energies

Description: The momentum transfer {Delta}k required for a photon to scatter from a target and emerge as a {rho}{sup 0} decreases as the photon energy k rises. For k &gt; 3 x 10{sup 14} eV, {Delta}k is small enough that the interaction cannot be localized to a single nucleus. At still higher energies, photons may coherently scatter elastically from bulk matter and emerge as a {rho}{sup 0}, in a manner akin to kaon regeneration. Constructive interference from the different nuclei coherently raises the cross section and the interaction probability rises linearly with energy. At energies above 10{sup 23} eV, coherent conversion is the dominant process; photons interact predominantly as {rho}{sup 0}. We compute the coherent scattering probabilities in slabs of lead, water and rock, and discuss the implications of the increased hadronic interaction probabilities for photons on ultra-high energy shower development.
Date: January 9, 2009
Creator: Couderc, Elsa & Klein, Spencer
Partner: UNT Libraries Government Documents Department

Search for axion-like particles using a variable baseline photon regeneration technique

Description: We report the first results of the GammeV experiment, a search for milli-eV mass particles with axion-like couplings to two photons. The search is performed using a 'light shining through a wall' technique where incident photons oscillate into new weakly interacting particles that are able to pass through the wall and subsequently regenerate back into detectable photons. The oscillation baseline of the apparatus is variable, thus allowing probes of different values of particle mass. We find no excess of events above background and are able to constrain the two-photon couplings of possible new scalar (pseudoscalar) particles to be less than 3.1 x 10 {sup -7} GeV {sup -1} (3.5 x 10{sup -7} GeV{sup -1}) in the limit of massless particles.
Date: October 1, 2007
Creator: Chou, A. S.; Wester, William Carl, III; Baumbaugh, A.; Gustafson, D.; Irizarry-Valle, Y.; Mazur, P. O. et al.
Partner: UNT Libraries Government Documents Department

Switchable cell trapping using superparamagnetic beads

Description: Ni{sub 81}Fe{sub 19} microwires are investigated as the basis of a switchable template for positioning magnetically-labeled neural Schwann cells. Magnetic transmission X-ray microscopy and micromagnetic modeling show that magnetic domain walls can be created or removed in zigzagged structures by an applied magnetic field. Schwann cells containing superparamagnetic beads are trapped by the field emanating from the domain walls. The design allows Schwann cells to be organized on a surface to form a connected network and then released from the surface if required. As aligned Schwann cells can guide nerve regeneration, this technique is of value for developing glial-neuronal co-culture models in the future treatment of peripheral nerve injuries.
Date: April 30, 2010
Creator: Bryan, M. T.; Smith, K. H.; Real, M. E.; Bashir, M. A.; Fry, P. W.; Fischer, P. et al.
Partner: UNT Libraries Government Documents Department