Status Report of Solar Standards coordinated by the Steering Committee on Solar Energy Standards Development contents (open access)

Status Report of Solar Standards coordinated by the Steering Committee on Solar Energy Standards Development contents

Solar standards are listed for each of the standards writing organizations associated with the Steering Committee. A complete list of approved standards, standards under development, and standards under revision is provided. (WHK)
Date: August 18, 1980
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Review of experiments (open access)

Review of experiments

A study was made to examine the effects which raising the ISA from 200 x 200 GeV to 400 x 400 GeV would have on the ''canonical'' experiments. These were ''canonical'' in the sense that they span the full range of foreseeable physics and have served as topics in previous Summer Studies and Workshops which resulted in quite explicit hardware designs and experimental goals. The study results indicate that all of the ''canonical'' experiments survive. Some are actually improved, some are unaffected, and some require changes which are suggested. In general, the 90/sup 0/ experiments are relatively unaffected. The single arm small angle spectrometer, the wide aperture (FATS-WASP) spectrometer and the Coulomb interference experiment have the largest number of modifications suggested. No uniqueness to these solutions are claimed, and there may be more desirable radical approaches. It is, however, felt that the 400 x 400 GeV ISA not only permits the work on conceptual experiments from previous Summer Studies to be taken over entirely, but indicates areas of improvement in many of them. Specifics of the individual experiments are discussed.
Date: August 18, 1977
Creator: Chang, C.; Yodh, G.; Cutts, D.; Lanou, R.; Engels, E.; Kramer, M. et al.
Object Type: Article
System: The UNT Digital Library
Intense transient magnetic-field generation by laser plasma (open access)

Intense transient magnetic-field generation by laser plasma

In a laser system, the return current of a laser generated plasma is conducted near a target to subject that target to the magnetic field thereof. In alternate embodiments the target may be either a small non-fusion object for testing under the magnetic field or a laser-fusion pellet. In the laser-fusion embodiment, the laser-fusion pellet is irradiated during the return current flow and the intense transient magnetic field is used to control the hot electrons thereof to hinder them from striking and heating the core of the irradiated laser-fusion pellet.
Date: August 18, 1981
Creator: Benjamin, R.F.
Object Type: Patent
System: The UNT Digital Library
Microscope and method of use (open access)

Microscope and method of use

A method and apparatus for electronically focusing and electronically scanning microscopic specimens are given. In the invention, visual images of even moving, living, opaque specimens can be acoustically obtained and viewed with virtually no time needed for processing (i.e., real time processing is used). And planar samples are not required. The specimens (if planar) need not be moved during scanning, although it will be desirable and possible to move or rotate nonplanar specimens (e.g., laser fusion targets) against the lens of the apparatus. No coupling fluid is needed, so specimens need not be wetted. A phase acoustic microscope is also made from the basic microscope components together with electronic mixers.
Date: August 18, 1981
Creator: Bongianni, W.L.
Object Type: Patent
System: The UNT Digital Library
TSTA compound cryopump (open access)

TSTA compound cryopump

The Tritium System Test Assembly (TSTA), at the Los Alamos Scientific Laboratory, is intended to demonstrate realistic fuel supply and cleanup scenarios for future fusion reactors. The vacuum pumps must be capable of handling large quantities of reactor exhaust gases consisting largely of mixtures of hydrogen and helium isotopes. Cryocondensing pumps will not pump helium at 4.2 K; while cryosorption pumps using molecular sieves or charcoal have good helium pumping speed, the adsorbent clogs with condensed hydrogen while pumping mixtures of both. A solution to this problem is a compound design whereby the first stage condenses the hydrogen and the second, or sorption, stage pumps the helium. The TSTA pump designed at Lawrence Livermore National Laboratory uses argon gas to cryotrap the helium in the helium-hydrogen mixture. The argon is sprayed directly onto the 4.2 K surface at a rate proportional to the helium flow rate, permitting continuous pumping of the helium-hydrogen mixtures in a single-stage pump. However, the possibility of differential desorption as a first stage in the TSTA gas separation cycle required the inclusion of a first-stage hydrogen isotope condenser. The design, performance, and operating characteristics are discussed.
Date: August 18, 1980
Creator: Batzer, T. H.; Patrick, R. E. & Call, W. R.
Object Type: Article
System: The UNT Digital Library
Evolution of the mirror machine (open access)

Evolution of the mirror machine

The history of the magnetic-mirror approach to a fusion reactor is primarily the history of our understanding and control of several crucial physics issues, coupled with progress in the technology of heating and confining a reacting plasma. The basic requirement of an MHD-stable plasma equilibrium was achieved following the early introduction of minimum-B multipolar magnetic fields. In refined form, the same magnetic-well principle carries over to our present experiments and to reactor designs. The higher frequency microinstabilities, arising from the non-Maxwellian particle distributions inherent in mirror machines, have gradually come under control as theoretical prescriptions for distribution functions have been applied in the experiments. Even with stability, the classical plasma leakage through the mirrors posed a serious question for reactor viability until the principle of electrostatic axial stoppering was applied in the tandem mirror configuration. Experiments to test this principle successfully demonstrated the substantial improvement in confinement predicted. Concurrent with advances in mirror plasma physics, development of both high-power neutral beam injectors and high-speed vacuum pumping techniques has played a crucial role in ongoing experiments. Together with superconducting magnets, cryogenic pumping, and high-power radiofrequency heating, these technologies have evolved to a level that extrapolates readily to meet the requirements of …
Date: August 18, 1983
Creator: Damm, C. C.
Object Type: Article
System: The UNT Digital Library
Shock Hugoniot measurements on Ta to 0. 78 TPa (open access)

Shock Hugoniot measurements on Ta to 0. 78 TPa

Symmetric impact shock Hugoniot measurements have been made on Ta with an electrically exploded foil gun system. The results obtained to date for the Hugoniot of Ta cover the range 0.19 to 0.78 TPa (impact velocities from 4.0 to 9.7 km/s) and agree with data obtained by other researchers to within 2.7% rms. Recent improvements in the system include electromagnetic shielding of impactor and target, continuous measurement of impactor velocity with a Fabry-Perot interferometer and computer-aided analysis of shot film. Conservative extrapolation from current operating conditions indicate that pressures of 1.1 to 1.5 TPa could be achieved with little difficulty.
Date: August 18, 1983
Creator: Froeschner, K. E.; Lee, R. S.; Chau, H. H. & Weingart, R. C.
Object Type: Article
System: The UNT Digital Library
Extension of the method of the small angle approximation: open detector (open access)

Extension of the method of the small angle approximation: open detector

We use the radiative transfer equation to study the multiple scattering undergone by a laser beam propagating through a turbid medium. During the propagation, we view the beam as first scattering into a narrow forward cone, and then into a diffuse pattern. To describe this process, we propose a systematic and practical method to combine the small angle approximation with the diffusion approximation. The method works when the scattering cross-section describing scattering from aerosols can be written as the sum of a gaussian sigma/sub s/ to describe scattering into small angles, and a term sigma/sub d/, that can be represented by the first two terms of a Legendre expansion to describe scattering into large/diffuse angles. We use a Green's function formalism to perform partial resummations and set up a hierarchy of approximations in the form of coupled radiative transfer equations to describe the scattering of radiation from small angles into large angles. The adjoint operator formalism then provides a simple way to obtain the net flux received by an open detector at any given point. Our approximations may be described rigorously as a power series expansion in sigma/sup 0//sub d//sigma/sup 0//sub s/, the ratio of the diffusion scattering cross-section to …
Date: August 18, 1986
Creator: Chitanvis, S.M. & Gerstl, S.A.W.
Object Type: Article
System: The UNT Digital Library
Radioactive-materials shipping-cask anticontamination enclosure (open access)

Radioactive-materials shipping-cask anticontamination enclosure

An anticontamination device for use in storing shipping casks for radioactive materials comprises (1) a seal plate assembly; (2) a double-layer plastic bag; and (3) a water management system or means for water management.
Date: August 18, 1981
Creator: Belmonte, M.S.; Davis, J.H. & Williams, D.A.
Object Type: Patent
System: The UNT Digital Library
The glycophorin A assay for somatic cell mutations in humans (open access)

The glycophorin A assay for somatic cell mutations in humans

In this report we briefly review our past experience and some new developments with the GPA assay. Particular emphasis will be placed on two areas that affect the utility of the GPA assay for human population monitoring. The first is our efforts to simplify the GPA assay to make it more generally available for large population studies. The second is to begin to understand some of the characteristics of human hemopoiesis which affect the accumulation and expression of mutant phenotype cells. 11 refs., 4 figs.
Date: August 18, 1989
Creator: Langlois, R.G.; Bigbee, W.L. & Jensen, R.H.
Object Type: Article
System: The UNT Digital Library
Model based controls and the AGS booster controls system architecture (open access)

Model based controls and the AGS booster controls system architecture

The Heavy Ion Transfer Line used to inject heavy ions created at the Tandem Van de Graaff into the Alternating Gradient Synchrotron (AGS) is briefly discussed, particularly as regards its control system. (LEW)
Date: August 18, 1987
Creator: Casella, R.A.
Object Type: Article
System: The UNT Digital Library
Measurement of Branching Fractions of Radiative Charm Decays (open access)

Measurement of Branching Fractions of Radiative Charm Decays

We present a measurement of the branching fractions for the Cabibbo-favored radiative decay, D{sup 0} {yields} {bar K}*{sup 0}{gamma}, and the Cabibbo-suppressed radiative decay, D{sup 0} {yields} {phi}{gamma}. These measurements are based on a data sample corresponding to an integrated luminosity of 387.1 fb{sup -1}, recorded with the BABAR detector at the PEP-II e{sup +}e{sup -} asymmetric-energy collider operating at center-of-mass energies 10.58 and 10.54 GeV. We measure the branching fractions relative to the well-studied decay D{sup 0} {yields} K{sup -}{pi}{sup +} and find {Beta}(D{sup 0} {yields} {bar K}*{sup 0}{gamma})/{Beta}(D{sup 0} {yields} K{sup -}{pi}{sup +}) = (8.43 {+-} 0.51 {+-} 0.70) x 10{sup -3} and {Beta}(D{sup 0} {yields} {phi}{gamma})/{Beta}(D{sup 0} {yields} K{sup -}{pi}{sup +}) = (7.15 {+-} 0.78 {+-} 0.69) x 10{sup -4}, where the first error is statistical and the second is systematic. This is the first measurement of {Beta}(D{sup 0} {yields} {bar K}*{sup 0} {gamma}).
Date: August 18, 2008
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Investigations of the R5(SixGe1-x)4 Intermetallic Compounds by X-Ray Resonant Magnetic Scattering (open access)

Investigations of the R5(SixGe1-x)4 Intermetallic Compounds by X-Ray Resonant Magnetic Scattering

The XRMS experiment on the Gd{sub 5}Ge{sub 4} system has shown that, below the Neel temperature, T{sub N} = 127 K, the magnetic unit cells is the same as the chemical unit cell. From azimuth scans and the Q dependence of the magnetic scattering, all three Gd sites in the structure were determined to be in the same magnetic space group Pnma. The magnetic moments are aligned along the c-axis and the c-components of the magnetic moments at the three different sites are equal. The ferromagnetic slabs are stacked antiferromagnetically along the b-direction. They found an unusual order parameter curve in Gd{sub 5}Ge{sub 4}. A spin-reorientation transition is a possibility in Gd{sub 5}Ge{sub 4}, which is similar to the Tb{sub 5}Ge{sub 4} case. Tb{sub 5}Ge{sub 4} possesses the same Sm{sub 5}Ge{sub 4}-type crystallographic structure and the same magnetic space group as Gd{sub 5}Ge{sub 4} does. The difference in magnetic structure is that Tb{sub 5}Ge{sub 4} has a canted one but Gd{sub 5}Ge{sub 4} has nearly a collinear one in the low temperature antiferromagnetic phase. The competition between the magneto-crystalline anisotropy and the nearest-neighbor magnetic exchange interactions may allow a 3-dimensional canted antiferromagnetic structure in Tb{sub 5}Ge{sub 4}. The spin-reorientation transition …
Date: August 18, 2008
Creator: Tan, Lizhi
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Promoting Energy Efficiency in Cement Making: The ENERGY STAR(R)for Industry Program (open access)

Promoting Energy Efficiency in Cement Making: The ENERGY STAR(R)for Industry Program

None
Date: August 18, 2007
Creator: Masanet, Eric & Worrell, Ernst
Object Type: Report
System: The UNT Digital Library
Evidence of half-metallic interface magnetism via local moment formation in Co based Heusler alloys (open access)

Evidence of half-metallic interface magnetism via local moment formation in Co based Heusler alloys

In this work we use a combination of x-ray magnetic circular and linear dichroism (XMCD and XMLD) techniques to examine the formation of local moments in Heusler alloys of the composition Co{sub 2}MnX (where X=Si or Al). The existence of local moments in a half-metallic system is reliant upon the band gap in the minority-spin states. By utilizing the element-specific nature of x-ray techniques we are able to explore the origin of the minority-spin band gap in the partial density of states (PDOS), via the degree of localization of moments on Co and Mn atoms. We observe a crucial difference in the localization of the Co moment when comparing Co{sub 2}MnSi (CMS) and Co{sub 2}MnAl (CMA) films that is consistent with the predicted larger minority-spin gap in the Co PDOS for CMS. These results provide important evidence for the dominant role of the Co minority-spin states in realizing half-metallic ferromagnetism (HMF) in these Heusler alloys. They also demonstrate a direct method for measuring the degree of interfacial HMF in the raw materials without the need for fabricating spin-transport devices.
Date: August 18, 2008
Creator: Telling, N. D.; Keatley, P. S.; van der Laan, G.; Hicken, R. J.; Arenholz, E.; Sakuraba, Y. et al.
Object Type: Article
System: The UNT Digital Library
Inductively Coupled Plasma: Fundamental Particle Investigations with Laser Ablation and Applications in Magnetic Sector Mass Spectrometry (open access)

Inductively Coupled Plasma: Fundamental Particle Investigations with Laser Ablation and Applications in Magnetic Sector Mass Spectrometry

Particle size effects and elemental fractionation in laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) are investigated with nanosecond and femtosecond laser ablation, differential mobility analysis, and magnetic sector ICP-MS. Laser pulse width was found to have a significant influence on the LA particle size distribution and the elemental composition of the aerosol and thus fractionation. Emission from individual particles from solution nebulization, glass, and a pressed powder pellet are observed with high speed digital photography. The presence of intact particles in an ICP is shown to be a likely source of fractionation. A technique for the online detection of stimulated elemental release from neural tissue using magnetic sector ICP-MS is described. Detection limits of 1 {micro}g L{sup -1} or better were found for P, Mn, Fe, Cu, and Zn in a 60 {micro}L injection in a physiological saline matrix.
Date: August 18, 2008
Creator: Saetveit, Nathan Joe
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Z' Physics at the LHC and the LHeC (open access)

Z' Physics at the LHC and the LHeC

The methods which can be employed to determine the properties of new neutral resonant states that may be observed in the Drell-Yan channel at the LHC are reviewed. If these states are sufficiently light we discuss how polarized ep scattering at the LHeC can assist in the determination of their couplings to the Standard Model (SM) fermions.
Date: August 18, 2008
Creator: Rizzo, Thomas G
Object Type: Article
System: The UNT Digital Library
Final Report: DOE/ID/14215 (open access)

Final Report: DOE/ID/14215

The proposed straw separation system developed in the research project harvests the large internode sections of the straw which has the greater potential as a feedstock for lignocellulosic ethanol production while leaving the chaff and nodes in the field. This strategy ensures sustainable agriculture by preventing the depletion of soil minerals, and it restores organic matter to the soil in amounts and particle sizes that accommodate farmers’ needs to keep tillage and fertilizer costs low. A ton of these nutrient-rich plant tissues contains as much as $10.55 worth of fertilizer (economic and energy benefits), in terms of nitrogen, phosphorus, potassium, and other nutrients provided to the soil when incorporated by tillage instead of being burned. Biomass conversion to fermentable sugars for the purpose of producing fuels, chemicals, and other industrial products is well understood. Most bioenergy strategies rely on low-cost fermentable sugars for sustainability and economic viability in the marketplace. Exploitation of the “whole crop”—specifically, wheat straw or other plant material currently regarded as residue or waste—is a practical approach for obtaining a reliable and low-cost source of sugars. However, industrial-scale production of sugars from wheat straw, while technically feasible, is plagued by obstacles related to capital costs, energy consumption, …
Date: August 18, 2008
Creator: Bryden, Kenneth; Hess, J. Richard; Ulrich, Thomas & Zemetra, Robert
Object Type: Report
System: The UNT Digital Library
Resonant Ultrasound Studies of Complex Transition Metal Oxides (open access)

Resonant Ultrasound Studies of Complex Transition Metal Oxides

Department of Energy EPSCoR The University of Mississippi Award: DE-FG02-04ER46121 Resonant Ultrasound Spectroscopy Studies of Complex Transition Metal Oxides The central thrust of this DOE funded research program has been to apply resonant ultrasound spectroscopy (RUS), an elegant and efficient method for determining the elastic stiffness constants of a crystal, to the complex and poorly understood class of materials known as transition metal oxides (TMOs). Perhaps the most interesting and challenging feature of TMOs is their strongly correlated behavior in which spin, lattice, and charge degrees of freedom are strongly coupled. Elastic constants are a measure of the interatomic potentials in a crystal and are thus sensitive probes into the atomic environment. This sensitivity makes RUS an ideal tool to study the coupling of phase transition order parameters to lattice strains. The most significant result of the project has been the construction of a high temperature RUS apparatus capable of making elastic constant measurements at temperatures as high as 1000 degrees Celsius. We have designed and built novel acoustic transducers which can operate as high as 600 degrees Celsius based on lithium niobate piezoelectric elements. For measurement between 600 to 1000 C, a buffer rod system is used in which …
Date: August 18, 2008
Creator: Bass, Henry & Gladden, J. R.
Object Type: Report
System: The UNT Digital Library
Improved Operation of the SSPX Spheromak (open access)

Improved Operation of the SSPX Spheromak

None
Date: August 18, 2005
Creator: Wood, R. D.; Hill, D. N.; Hooper, E. B.; Woodruff, S.; McLean, H. S. & Stallard, B. W.
Object Type: Article
System: The UNT Digital Library
Novel Bioplastics and biocomposites from Vegetable Oils (open access)

Novel Bioplastics and biocomposites from Vegetable Oils

Polymeric materials have been prevalent in our everyday lives for quite a long time. Most of today's polymeric materials are derived from nonrenewable petroleum-based feedstocks. Instabilities in the regions where petroleum is drilled, along with an increased demand in petroleum, have driven the price of crude oil to record high prices. This, in effect, increases the price of petroleum-based polymeric materials, which has caused a heightened awareness of renewable alternatives for polymeric feedstocks. Cellulose, starch, proteins and natural oils have all been examined as possible polymeric feedstocks. Natural oils are commercially available on a large scale and are relatively cheap. It is projected that the U.S. alone will produce 21 billion pounds of soybean oil in the period 2008/2009. Natural oils also have the advantages of inherent biodegradability, low toxicity, high purity and ready availability. Most natural oils possess a triglyceride structure as shown in Figure 1. Most natural oils have a unique distribution of fatty acid side chains, along with varying degrees of unsaturation per triglyceride. Common fatty acid side chains in naturally occurring oils are palmitic acid (C16:0), a 16 carbon fatty acid with no unsaturation; stearic acid (C18:0), an 18 carbon fatty acid with no unsaturation; oleic …
Date: August 18, 2008
Creator: Henna, Phillip H.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Synthesis and Characterization of Smart Block Copolymers for Biomineralization and Biomedical Applications (open access)

Synthesis and Characterization of Smart Block Copolymers for Biomineralization and Biomedical Applications

Self-assembly is a powerful tool in forming structures with nanoscale dimensions. Self-assembly of macromolecules provides an efficient and rapid pathway for the formation of structures from the nanometer to micrometer range that are difficult, if not impossible to obtain by conventional lithographic techniques [1]. Depending on the morphologies obtained (size, shape, periodicity, etc.) these self-assembled systems have already been applied or shown to be useful for a number of applications in nanotechnology [2], biomineralization [3, 4], drug delivery [5, 6] and gene therapy [7]. In this respect, amphiphilic block copolymers that self-organize in solution have been found to be very versatile [1]. In recent years, polymer-micellar systems have been designed that are adaptable to their environment and able to respond in a controlled manner to external stimuli. In short, synthesis of 'nanoscale objects' that exhibit 'stimulus-responsive' properties is a topic gathering momentum, because their behavior is reminiscent of that exhibited by proteins [8]. By integrating environmentally sensitive homopolymers into amphiphilic block copolymers, smart block copolymers with self assembled supramolecular structures that exhibit stimuli or environmentally responsive properties can be obtained [1]. Several synthetic polymers are known to have environmentally responsive properties. Changes in the physical, chemical or biochemical environment of …
Date: August 18, 2008
Creator: Kanapathipillai, Mathumai
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Effects of Substrate and Co-Culture on Neural Progenitor Cell Differentiation (open access)

Effects of Substrate and Co-Culture on Neural Progenitor Cell Differentiation

In recent years the study of stem and progenitor cells has moved to the forefront of research. Since the isolation of human hematopoietic stem cells in 1988 and the subsequent discovery of a self renewing population of multipotent cells in many tissues, many researchers have envisioned a better understanding of development and potential clinical usage in intractable diseases. Both these goals, however, depend on a solid understanding of the intracellular and extracellular forces that cause stem cells to differentiate to a specific cell fate. Many diseases of large scale cell loss have been suggested as candidates for stem cell based treatments. It is proposed that replacing the function of the damaged or defective cells by specific differentiation of stem or progenitor cells could treat the disease. Before cells can be directed to specific lineages, the mechanisms of differentiation must be better understood. Differentiation in vivo is an intensively complex system that is difficult to study. The goal of this research is to develop further understanding of the effects of soluble and extracellular matrix (ECM) cues on the differentiation of neural progenitor cells with the use of a simplified in vitro culture system. Specific research objectives are to study the differentiation …
Date: August 18, 2008
Creator: Jones, Erin Boote
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Investment and Upgrade in Distributed Generation under Uncertainty (open access)

Investment and Upgrade in Distributed Generation under Uncertainty

The ongoing deregulation of electricity industries worldwide is providing incentives for microgrids to use small-scale distributed generation (DG) and combined heat and power (CHP) applications via heat exchangers (HXs) to meet local energy loads. Although the electric-only efficiency of DG is lower than that of central-station production, relatively high tariff rates and the potential for CHP applications increase the attraction of on-site generation. Nevertheless, a microgrid contemplatingthe installation of gas-fired DG has to be aware of the uncertainty in the natural gas price. Treatment of uncertainty via real options increases the value of the investment opportunity, which then delays the adoption decision as the opportunity cost of exercising the investment option increases as well. In this paper, we take the perspective of a microgrid that can proceed in a sequential manner with DG capacity and HX investment in order to reduce its exposure to risk from natural gas price volatility. In particular, with the availability of the HX, the microgrid faces a tradeoff between reducing its exposure to the natural gas price and maximising its cost savings. By varying the volatility parameter, we find that the microgrid prefers a direct investment strategy for low levels of volatility and a sequential …
Date: August 18, 2008
Creator: Siddiqui, Afzal & Maribu, Karl
Object Type: Article
System: The UNT Digital Library