Low cost solar collector of a packed bed design (open access)

Low cost solar collector of a packed bed design

Two solar collectors using a pebble bed design were constructed and tested using air as the heat exchange media. One collector had pebbles of metallurgical grade coke, and the other had a frothy volcanic material called scoria. The highly irregular surface of such vesicular material should increase the path distance for the air and the surface exposed cavities should give some honeycomb effect. Both should yield greater efficiency. Actual testing shows the efficiencies to be comparable with other air collectors. Thus the advantages of the pebble bed lie in the availability of the bed material, its thermal and radiation stability, and its shielding of underlying collector materials from ultraviolet radiation. Several pebble bed collectors using water as the heat exchange media were constructed. However, basic problems prevented effective testing, and it is concluded that pebble bed collectors using water are impractical.
Date: July 29, 1977
Creator: Simpson, D.R.
Object Type: Report
System: The UNT Digital Library
Control of beam dynamics in high energy induction linacs (open access)

Control of beam dynamics in high energy induction linacs

The Advent of laser-ion-guiding in the Advanced test Accelerator along with the development of accelerator cavities optimized with respect to beam breakup coupling impedence now make it possible to consider a new class of high current, high emergy linear induction accelerators. The control of the beam breakup and other instabilities by laser guiding and by various magnetic focusing schemes will be discussed along with the scaling laws for the design of such machines to minimize the growth of the beam breakup instability. Many linacs, particularly induction linacs are limited in performance by the beam breakup (BBU) instability. The instability is found in two forms. In the first form the accelerating cavities communicate with one another through interaction with the beam and through propagation of cavity fields through the accelerator structure. In the second form which is the more virulent of the two, the cavities couple to each other only through their interactions with the beam. It is this second form of PPU that will be discussed in this paper.
Date: July 29, 1986
Creator: Caporaso, G.J.
Object Type: Article
System: The UNT Digital Library
TMX tandem-mirror experiments and thermal-barrier theoretical studies (open access)

TMX tandem-mirror experiments and thermal-barrier theoretical studies

This paper describes recent analysis of energy confinement in the Tandem Mirror Experiment (TMX). TMX data also indicates that warm plasma limits the amplitude of the anisotropy driven Alfven ion cyclotron (AIC) mode. Theoretical calculations show strong AIC stabilization with off-normal beam injection as planned in TMX-U and MFTF-B. This paper reports results of theoretical analysis of hot electrons in thermal barriers including electron heating calculations by Monte Carlo and Fokker-Planck codes and analysis of hot electron MHD and microinstability. Initial results from the TMX-U experiment are presented which show the presence of sloshing ions.
Date: July 29, 1982
Creator: Simonen, T. C.; Baldwin, D. E. & Allen, S. L.
Object Type: Article
System: The UNT Digital Library
TMX tandem-mirror experiments and thermal-barrier theoretical studies (open access)

TMX tandem-mirror experiments and thermal-barrier theoretical studies

This paper describes recent analysis of energy confinement in the Tandem Mirror Experiment (TMX). TMX data also indicates that warm plasma limits the amplitude of the anisotropy driven Alfven ion cyclotron (AIC) mode. Theoretical calculations show strong AIC stabilization with off-normal beam injection as planned in TMX-U and MFTF-B. This paper reports results of theoretical analysis of hot electrons in thermal barriers including electron heating calculations by Monte Carlo and Fokker-Planck codes and analysis of hot electron MHD and microinstability. Initial results from the TMX-U experiment are presented which show the presence of sloshing ions.
Date: July 29, 1982
Creator: Simonen, T. C.; Baldwin, D. E. & Allen, S. L.
Object Type: Article
System: The UNT Digital Library
Thermoelectric refrigerator having improved temperature-stabilization means (open access)

Thermoelectric refrigerator having improved temperature-stabilization means

A control system for thermoelectric refrigerators is disclosed. The thermoelectric refrigerator includes at least one thermoelectric element that undergoes a first order change at a predetermined critical temperature. The element functions as a thermoelectric refrigerator element above the critical temperature but discontinuously ceases to function as a thermoelectric refrigerator element below the critical temperature. One example of such an arrangement includes thermoelectric refrigerator elements which are superconductors. The transition temperature of one of the superconductor elements is selected as the temperature control point of the refrigerator. When the refrigerator attempts to cool below the point, the metals become superconductors losing their ability to perform as a thermoelectric refrigerator. An extremely accurate, first-order control is realized.
Date: July 29, 1981
Creator: Falco, Charles M.
Object Type: Patent
System: The UNT Digital Library
Method for determining the hardness of strain hardening articles of tungsten-nickel-iron alloy (open access)

Method for determining the hardness of strain hardening articles of tungsten-nickel-iron alloy

The present invention is directed to a rapid nondestructive method for determining the extent of strain hardening in an article of tungsten-nickel-iron alloy. The method comprises saturating the article with a magnetic field from a permanent magnet, measuring the magnetic flux emanating from the article, comparing the measurements of the magnetic flux emanating from the article with measured magnetic fluxes from similarly shaped standards of the alloy with known amounts of strain hardening to determine the hardness.
Date: July 29, 1981
Creator: Wallace, S.A.
Object Type: Patent
System: The UNT Digital Library
Electrochemical cell and negative electrode therefor. [Li-Al anode] (open access)

Electrochemical cell and negative electrode therefor. [Li-Al anode]

A secondary electrochemical cell is described with the positive and negative electrodes separated by a molten salt electrolyte with the negative electrode comprising a particulate mixture of lithium-aluminum alloy and electrolyte and an additive selected from graphitized carbon, Raney iron or mixtures thereof. The lithium-aluminum alloy is present in the range of from about 45 to about 80% by volume of the negative electrode, and the electrolyte is present in an amount not less than about 10% by volume of the negative electrode. The additive of graphitized carbon is present in the range of from about 1 to about 10% by volume of the negative electrode, and the Raney iron additive is present in the range of from about 3 to about 10% by volume of the negative electrode.
Date: July 29, 1981
Creator: Kaun, T.D.
Object Type: Patent
System: The UNT Digital Library
Use of gamma ray strength functions for predicting the neutron capture cross section of /sup 88/Y (open access)

Use of gamma ray strength functions for predicting the neutron capture cross section of /sup 88/Y

The present study indicates that the estimation of the gamma-ray strength function is the approach least subject to error when unmeasured capture cross sections are to be computed. An estimate is given for the /sup 88/..gamma..(n,..gamma..) cross section.
Date: July 29, 1977
Creator: Gardner, D. G. & Gardner, M. A.
Object Type: Report
System: The UNT Digital Library
Third millenium ideal gas and condensed phase thermochemical database for combustion (with update from active thermochemical tables). (open access)

Third millenium ideal gas and condensed phase thermochemical database for combustion (with update from active thermochemical tables).

The thermochemical database of species involved in combustion processes is and has been available for free use for over 25 years. It was first published in print in 1984, approximately 8 years after it was first assembled, and contained 215 species at the time. This is the 7th printed edition and most likely will be the last one in print in the present format, which involves substantial manual labor. The database currently contains more than 1300 species, specifically organic molecules and radicals, but also inorganic species connected to combustion and air pollution. Since 1991 this database is freely available on the internet, at the Technion-IIT ftp server, and it is continuously expanded and corrected. The database is mirrored daily at an official mirror site, and at random at about a dozen unofficial mirror and 'finger' sites. The present edition contains numerous corrections and many recalculations of data of provisory type by the G3//B3LYP method, a high-accuracy composite ab initio calculation. About 300 species are newly calculated and are not yet published elsewhere. In anticipation of the full coupling, which is under development, the database started incorporating the available (as yet unpublished) values from Active Thermochemical Tables. The electronic version now …
Date: July 29, 2005
Creator: Burcat, A.; Ruscic, B.; Chemistry & Tech., Technion - Israel Inst. of
Object Type: Report
System: The UNT Digital Library
Rh(I)-Catalyzed Direct Arylation of Pyridines and Quinolines (open access)

Rh(I)-Catalyzed Direct Arylation of Pyridines and Quinolines

The pyridine and quinoline nuclei are privileged scaffolds that occupy a central role in many medicinally relevant compounds. Consequently, methods for their expeditious functionalization are of immediate interest. However, despite the immense importance of transition-metal catalyzed cross-coupling for the functionalization of aromatic scaffolds, general solutions for coupling 2-pyridyl organometallics with aryl halides have only recently been presented. Direct arylation at the ortho position of pyridine would constitute an even more efficient approach because it eliminates the need for the stoichiometric preparation and isolation of 2-pyridyl organometallics. Progress towards this goal has been achieved by activation of the pyridine nucleus for arylation via conversion to the corresponding pyridine N-oxide or N-iminopyridinium ylide. However, this approach necessitates two additional steps: activation of the pyridine or quinoline starting material, and then unmasking the arylated product. The use of pyridines directly would clearly represent the ideal situation both in terms of cost and simplicity. We now wish to document our efforts in this vein, culminating in an operationally simple Rh(I)-catalyzed direct arylation of pyridines and quinolines. We recently developed an electron-rich Rh(I) system for catalytic alkylation at the ortho position of pyridines and quinolines with alkenes. Therefore, we initially focused our attention on the …
Date: July 29, 2008
Creator: Berman, Ashley; Lewis, Jared; Bergman, Robert & Ellman, Jonathan
Object Type: Article
System: The UNT Digital Library
ELECTRICAL PROPERTIES OF ORGANIC SOLIDS. I. KINETICS AND MECHANISMOF CONDUCTIVITY OF METAL-FREE PHTHALOCYANINE (open access)

ELECTRICAL PROPERTIES OF ORGANIC SOLIDS. I. KINETICS AND MECHANISMOF CONDUCTIVITY OF METAL-FREE PHTHALOCYANINE

Techniques involving the use of high-intensity short-duration light pulses have been applied t o the study of the kinetics of photoconductivity in films of metal-free phthalocyanine. These experiments, in conjunction with measurements of steady-state photoconductivity, are consistent with the following scheme. The principal route for the formation of charge carriers is via the first excited singlet state, although the lowest triplet state can, t o some extent, contribute to charge - carrier production. The mobility of the carriers is low and is concentration-dependent, being lower at higher carrier concentration. The decay of the photocurrent is the result of a diffusion-limited bimolecular recombination, with a capture radius of approximately one molecular diameter. The experiments indicate that carriers produced thermally in the dark do not interact with light-produced carriers.
Date: July 29, 1959
Creator: Tollin, Gordon; Kearns, David R. & Calvin, Melvin.
Object Type: Report
System: The UNT Digital Library
VARIABILITY STUDY WITH FRIT 510 TO SUPPORT A SECOND TANK 40 DECANT (open access)

VARIABILITY STUDY WITH FRIT 510 TO SUPPORT A SECOND TANK 40 DECANT

Sludge Batch 4 (SB4) is currently being processed in the Defense Waste Processing Facility (DWPF) using Frit 510. The slurry pumps in Tank 40 are experiencing in-leakage of bearing water, which is causing the sludge slurry in Tank 40 to become dilute at a rapid rate. Currently, the DWPF is removing this dilution water by performing caustic boiling during the Sludge Receipt and Adjustment Tank (SRAT) cycle. In order to alleviate prolonged SRAT cycle times, which may eventually impact canister production rates, the Liquid Waste Organization (LWO) performed a 100K gallon supernate decant of Tank 40 in April 2008. SRNL performed a supplemental glass variability study to support the April 2008 100K gallon decant incorporating the impact of coupled operations (addition of the Actinide Removal Process (ARP) stream). Recently LWO requested that SRNL assess the impact of a second decant (up to 100K gallon) to the Frit 510-SB4 system. This second decant occurred in June 2008. LWO provided nominal compositions on May 6, 2008 representing Tank 40 prior to the second decant, following the second decant, and the SB4 Heel prior to blending with Tank 51 to constitute SB5. Paper study assessments were performed for these options based on sludge-only …
Date: July 29, 2008
Creator: Raszewski, F; Tommy Edwards, T; David Peeler, D; David Best, D; Irene Reamer, I & Phyllis Workman, P
Object Type: Report
System: The UNT Digital Library
Direct Photons at RHIC (open access)

Direct Photons at RHIC

Direct photons are ideal tools to investigate kinematical and thermodynamical conditions of heavy ion collisions since they are emitted from all stages of the collision and once produced they leave the interaction region without further modification by the medium. The PHENIX experiment at RHIC has measured direct photon production in p+p and Au+Au collisions at 200 GeV over a wide transverse momentum (p{sub T}) range. The p+p measurements allow a fundamental test of QCD, and serve as a baseline when we try to disentangle more complex mechanisms producing high p{sub T} direct photons in Au+Au. As for thermal photons in Au+Au we overcome the difficulties due to the large background from hadronic decays by measuring 'almost real' virtual photons which appear as low invariant mass e{sup +}e{sup -} pairs: a significant excess of direct photons is measured above the above next-to-leading order perturbative quantum chromodynamics calculations. Additional insights on the origin of direct photons can be gained with the study of the azimuthal anisotropy which benefits from the increased statistics and reaction plane resolution achieved in RHIC Year-7 data.
Date: July 29, 2008
Creator: Gabor,D.
Object Type: Article
System: The UNT Digital Library
ELECTRICAL PROPERTIES OF ORGANIC SOLIDS. II: EFFECTS OF ADDEDELECTRON ACCEPTOR ON METAL-FREE PHTHALOCYANINE (open access)

ELECTRICAL PROPERTIES OF ORGANIC SOLIDS. II: EFFECTS OF ADDEDELECTRON ACCEPTOR ON METAL-FREE PHTHALOCYANINE

The addition of ortho-chloranil to the surface of films of metal-free phthalocyanine has been found (a) to increase the dark conductivity of such films by as much as 10{sup 7}, (b) to increase the steady-state photoconductivity by as much as 10{sup 5}, and (c) to result in the formation of unpaired electrons whose concentration decreases reversibly as a result of illumination. These systems exhibit a light-induced polarization, the phthalocyanine layer becoming more positive with respect t o the ortho-chloranil layer. Kinetic studies demonstrate that, upon illumination, a single process (time constant = 40 seconds) results in the increase in conductivity, the decrease in unpaired spins, and the increase in polarization. The results are consistent with the following scheme. An electron transfer from phthalocyanine to ortho-chloranil occurs in the dark at room temperature, producing holes in the phthalocyanine layer and ortho-chloranil negative ion radicals (high conductivity, ESR signal). Illumination results in the transfer of an electron from an excited phthalocyanine molecule to the ortho-chloranil negative ion, producing further phthalocyanine holes and ortho-chloranil double-negative ion (increase in conductivity, increase in polarization, decrease in ESR signal). By equating spin concentration with charge - carrier concentration (phthalocyanine holes) it is possible to calculate a …
Date: July 29, 1959
Creator: Kearns, David R.; Tollin, Gordon & Calvin, Melvin
Object Type: Report
System: The UNT Digital Library
Smoothing of Military Mirrors by Novel Surface Alloying and Melting Technique (open access)

Smoothing of Military Mirrors by Novel Surface Alloying and Melting Technique

None
Date: July 29, 2004
Creator: Williams, J.M. (BronteK Delta Corp.)
Object Type: Report
System: The UNT Digital Library
The Little Randall-Sundrum Model at the LHC (open access)

The Little Randall-Sundrum Model at the LHC

We present a predictive warped model of flavor, cut off at an ultraviolet scale {Omicron}(10{sup 3}) TeV, called the 'Little Randall-Sundrum (LRS)' model. This model corresponds to a volume-truncation, by a factor y {approx} 6, of the RS scenario and is holographically dual to dynamics with number of colors larger by y. With separate gauge and flavor dynamics, several unwanted contributions to precision electroweak, Zb{bar b}, and flavor observables are suppressed in the LRS framework, compared with the corresponding RS case. The LRS truncation leads to a significant enhancement of the clean (golden) di-lepton LHC signals, by {Omicron}(y{sup 3}).
Date: July 29, 2008
Creator: Davoudiasl, H.
Object Type: Article
System: The UNT Digital Library
Chapter 9: Model Systems for Formation and Dissolution of Calcium Phosphate Minerals (open access)

Chapter 9: Model Systems for Formation and Dissolution of Calcium Phosphate Minerals

Calcium phosphates are the mineral component of bones and teeth. As such there is great interest in understanding the physical mechanisms that underlie their growth, dissolution, and phase stability. Control is often achieved at the cellular level by the manipulation of solution states and the use of crystal growth modulators such as peptides or other organic molecules. This chapter begins with a discussion of solution speciation in body fluids and relates this to important crystal growth parameters such as the supersaturation, pH, ionic strength and the ratio of calcium to phosphate activities. We then discuss the use of scanning probe microscopy as a tool to measure surface kinetics of mineral surfaces evolving in simplified solutions. The two primary themes that we will touch on are the use of microenvironments that temporally evolve the solution state to control growth and dissolution; and the use of various growth modifiers that interact with the solution species or with mineral surfaces to shift growth away from the lowest energy facetted forms. The study of synthetic minerals in simplified solution lays the foundation for understand mineralization process in more complex environments found in the body.
Date: July 29, 2006
Creator: Orme, C. A. & Giocondi, J. L.
Object Type: Book
System: The UNT Digital Library
Thermoelasticity of SSP Materials: An Integrated Ultrasonic and X-radiation Study (open access)

Thermoelasticity of SSP Materials: An Integrated Ultrasonic and X-radiation Study

It has been a very productive year for accomplishing the tasks outlined in the original proposal. Quite a few crystalline materials [tantalum (Ta), molybdenum (Mo), cerium (Ce) beryllium (Be)] and amorphous materials [zirconium tungstate (ZrW2O8), SiO2, and germanium diselenide (GeSe2) glasses] have been assessed at high pressures up to 12 GPa and acoustic velocities and densities have been obtained simultaneously using our unique technique. Major activities include sample preparation, high pressure cell assembly testing, and conducting ultrasonic and X-ray diffraction measurements at BNL as well as resonance ultrasonic spectroscopy (RUS) measurements at UCLA on appropriate samples. Sample preparations for Ce and Be were made at Los Alamos National Lab for which special grades and specialized machining of the sample are required. Pilot experiments for optimizing high pressure cell assemblies were conducted using the 1000-ton multi-anvil press (USCA-1000) in the High Pressure Lab at Stony Brook, and simultaneous ultrasonic and X-ray diffraction experiments were conducted using the DDIA apparatus installed at X17B2 of NSLS at BNL. New data analysis protocols have been developed for deriving density of amorphous materials at high pressure and therefore its equation of state. Following on previous years effort, attempts have been made to derive single crystal …
Date: July 29, 2008
Creator: Li, Baosheng
Object Type: Report
System: The UNT Digital Library
Economic model of pipeline transportation systems (open access)

Economic model of pipeline transportation systems

The objective of the work reported here was to develop a model which could be used to assess the economic effects of energy-conservative technological innovations upon the pipeline industry. The model is a dynamic simulator which accepts inputs of two classes: the physical description (design parameters, fluid properties, and financial structures) of the system to be studied, and the postulated market (throughput and price) projection. The model consists of time-independent submodels: the fluidics model which simulates the physical behavior of the system, and the financial model which operates upon the output of the fluidics model to calculate the economics outputs. Any of a number of existing fluidics models can be used in addition to that developed as a part of this study. The financial model, known as the Systems, Science and Software (S/sup 3/) Financial Projection Model, contains user options whereby pipeline-peculiar characteristics can be removed and/or modified, so that the model can be applied to virtually any kind of business enterprise. The several dozen outputs are of two classes: the energetics and the economics. The energetics outputs of primary interest are the energy intensity, also called unit energy consumption, and the total energy consumed. The primary economics outputs are …
Date: July 29, 1977
Creator: Banks, W. F.
Object Type: Report
System: The UNT Digital Library
Final Report of Investigation of the Acoustic Decay Instability in Laser Plasma Interaction (open access)

Final Report of Investigation of the Acoustic Decay Instability in Laser Plasma Interaction

we have made extensive studies of the Ion Acoustic Decay Instability (IADI) in laser-produced plasmas using the Janus (Phoenix) laser at LLNL. We found that the threshold is quite low and that, in planar plasmas, it can be reduced to homogeneous-plasma, collisional values. These observations are consistent with the plasma-density profiles calculated by hydrodynamic simulations using the LASNEX computer code run with a flux limiter of f = 0.1. We have designed experiments to study the IADI in larger plasmas using the Nova laser. 2 refs., 1 fig.
Date: July 29, 1991
Creator: Young, P.; Drake, P.; Estabrook; Mizuno, K. & De Groot, J.S.
Object Type: Report
System: The UNT Digital Library
Corrosion Evaluation of Tank 40 Leak Detection Box (open access)

Corrosion Evaluation of Tank 40 Leak Detection Box

'Leak detection from the transfer lines in the tank farm has been a concern for many years because of the need to minimize exposure of personnel and contamination of the environment. The leak detection box (LDB) is one line of defense, which must be maintained to meet this objective. The evaluation of a failed LDB was one item from an action plan aimed at minimizing the degradation of LDBs. The Tank 40 LDB, which failed in service, was dug up and shipped to SRTC for evaluation. During a video inspection while in service, this LDB was found to have black tubercles on the interior, which suggested possible microbial involvement. The failure point, however, was believed to have occurred in the drain line from the transfer line jacket. Visual, metallurgical, and biological analyses were performed on the LDB. The analysis results showed that there was not any adverse microbiological growth or significant localized corrosion. The corrosion of the LDB was caused by exposure to aqueous environments and was typical of carbon steel pipes in soil environments.'
Date: July 29, 1999
Creator: Mickalonis, J.I.
Object Type: Report
System: The UNT Digital Library
Verifying seismic design of nuclear reactors by testing. Volume 2: appendix, theoretical discussions (open access)

Verifying seismic design of nuclear reactors by testing. Volume 2: appendix, theoretical discussions

Theoretical discussions on seismic design testing are presented under the following appendix headings: system functions, pulse optimization program, system identification, and motion response calculations from inertance measurements of a nuclear power plant.
Date: July 29, 1979
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Roll compaction and granulation system for nuclear fuel material (open access)

Roll compaction and granulation system for nuclear fuel material

A roll compaction and roll granulation system has been designed and fabricated to replace conventional preslugging and crushing operations typically used in the fabrication of mixed oxide nuclear fuel pellets. This equipment will be of maintenance advantage with only the compaction and granulation rolls inside containment. The prototype is being tested and the results will be reported within a year.
Date: July 29, 1981
Creator: Goldmann, L.H. Jr. & Holley, C.C.
Object Type: Article
System: The UNT Digital Library
Cryogenic analytical tools for LHe distribution system design (open access)

Cryogenic analytical tools for LHe distribution system design

The two computer programs presented in this paper are both fundamentally general in that they could be applied to other magnet systems. In addition to MFTF-B analyses, these programs will be used on current and future GDC superconducting magnet projects. Future extended capabilities will include transient heating and flow conditions for THERMOSIPHON and multiple magnet quench features for MAGPRS.
Date: July 29, 1983
Creator: Johnson, R.R.
Object Type: Report
System: The UNT Digital Library