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Oxidation of Reduced Sulfur Species: Carbon Disulfide

Description: Article on the oxidation of reduced sulfur species and carbon disulfide.
Date: August 4, 2014
Creator: Glarborg, Peter; Halaburt, Birgitte; Marshall, Paul; Guillory, Adrian; Troe, Jürgen; Thellefsen, Morten et al.
Partner: UNT College of Arts and Sciences

Multi-site genetic modulation of monolignol biosynthesis suggests new routes for formation of syringyl lignin and wall-bound ferulic acid in alfalfa (Medicago sativa L.)

Description: Article on multi-site genetic modulation of monolignol biosynthesis suggests new routes for formation of syringyl lignin and wall-bound ferulic acid in alfalfa (Medicago sativa L.).
Date: August 30, 2006
Creator: Chen, Fang; Reddy, M. S. Srinivasa; Temple, Stephen; Jackson, Lisa A.; Shadle, Gail L. & Dixon, R. A.
Partner: UNT College of Arts and Sciences

Structural and compositional modifications in lignin of transgenic alfalfa down-regulated in caffeic acid 3-O-methyltransferase and caffeoyl coenzyme A 3-O-methyltransferase

Description: Article on the structural and compositional modifications in lignin of transgenic alfalfa down-regulated in caffeic acid 3-O-methyltransferase and caffeoyl coenzyme A 3-O-methyltransferase.
Date: July 8, 2002
Creator: Marita, Jane M.; Ralph, John; Hatfield, Ronald D.; Guo, Dianjing; Chen, Fang & Dixon, R. A.
Partner: UNT College of Arts and Sciences

Alternatives to conventional diesel fuel-some potential implications of California's TAC decision on diesel particulate.

Description: Limitations on the use of petroleum-based diesel fuel in California could occur pursuant to the 1998 declaration by California's Air Resources Board (CARB) that the particulate matter component of diesel exhaust is a carcinogen, therefore a toxic air contaminant (TAC) subject to provisions of the state's Proposition 65. It is the declared intention of CARB not to ban or restrict diesel fuel, per se, at this time. Assuming no total ban, Argonne National Laboratory (ANL) explored two feasible ''mid-course'' strategies. (1) Increased penetration of natural gas and greater gasoline use in the transportation fuels market, to the extent that some compression-ignition (CI) applications revert to spark-ignition (SI) engines. (2) New specifications requiring diesel fuel reformulation based on exhaust products of individual diesel fuel constituents. Each of these alternatives results in some degree of (conventional) diesel displacement. In the first case, diesel fuel is assumed admissible for ignition assistance as a pilot fuel in natural gas (NG)-powered heavy-duty vehicles, and gasoline demand in California increases by 32.2 million liters per day overall, about 21 percent above projected 2010 baseline demand. Natural gas demand increases by 13.6 million diesel liter equivalents per day, about 7 percent above projected (total) consumption level. In the second case, compression-ignition engines utilize substitutes for petroleum-based diesel having similar ignition and performance properties. For each case we estimated localized air emission plus generalized greenhouse gas and energy changes. Economic implications of vehicle and engine replacement were not evaluated.
Date: August 10, 1999
Creator: Eberhardt, J. J.; Rote, D. M.; Saricks, C. L. & Stodolsky, F.
Partner: UNT Libraries Government Documents Department

Performance Assessment Uncertainty Analysis for Japan's HLW Program Feasibility Study (H12)

Description: Most HLW programs in the world recognize that any estimate of long-term radiological performance must be couched in terms of the uncertainties derived from natural variation, changes through time and lack of knowledge about the essential processes. The Japan Nuclear Cycle Development Institute followed a relatively standard procedure to address two major categories of uncertainty. First, a FEatures, Events and Processes (FEPs) listing, screening and grouping activity was pursued in order to define the range of uncertainty in system processes as well as possible variations in engineering design. A reference and many alternative cases representing various groups of FEPs were defined and individual numerical simulations performed for each to quantify the range of conceptual uncertainty. Second, parameter distributions were developed for the reference case to represent the uncertainty in the strength of these processes, the sequencing of activities and geometric variations. Both point estimates using high and low values for individual parameters as well as a probabilistic analysis were performed to estimate parameter uncertainty. A brief description of the conceptual model uncertainty analysis is presented. This paper focuses on presenting the details of the probabilistic parameter uncertainty assessment.
Date: August 30, 1999
Creator: BABA,T.; ISHIGURO,K.; ISHIHARA,Y.; SAWADA,A.; UMEKI,H.; WAKASUGI,K. et al.
Partner: UNT Libraries Government Documents Department

Development of practical damage-mapping and inspection systems

Description: We have developed and are continuing to refine semi-automated technology for the detection and inspection of surface and bulk defects and damage in large laser optics Different manifestations of the DAMOCLES system (Damage and Artifact Mapping Of Coherent-Laser-Exposed Substrates) provide an effective and economical means of being able to detect, map and characterize surface and bulk defects which may become precursors of massive damage in optics when subjected to high-fluence laser irradiation Subsequent morphology and evolution of damage due to laser irradiation can be tracked efficiently The strength of the Damocles system is that it allows for immediate visual observation of defects in an entire optic, which can range up to l-meter dimensions, while also being able to provide digital map and magnified images of the defects with resolutions better than 5 µm.
Date: August 19, 1998
Creator: Rainer, F.
Partner: UNT Libraries Government Documents Department

Laser-generated metallic hydrogen

Description: Hydrogen reaches the minimum conductivity of a metal at 140 GPa (1.4 Mbar) and 3000 K. These conditions were achieved using a two-stage light-gas gun. The authors have investigated computationally the use of a laser-heated hohlraum to shock compress hydrogen to these conditions in samples sufficiently thin that the metallic fluid might be quenched metastably on release of dynamic pressure. A configuration was found such that the duration of maximum pressure is sufficiently long that the hydrogen film cools by thermal conduction before pressure is released.
Date: August 27, 1999
Creator: Nellis, W J & Pollaine, S M
Partner: UNT Libraries Government Documents Department

Highlights of B physics at CDF

Description: The CDF experiment at the Fermilab Tevatron collider has produced many B physics results. Recent measurements on B meson masses, B lifetimes, B branching ratios, limits on rare B decays, and B flavour tagging studies are reviewed.
Date: August 1, 1995
Creator: Paulini, M.
Partner: UNT Libraries Government Documents Department

Energy Systems Division Overview

Description: This report presents an overview of the research programs from the energy systems division in the form of viewgraphs.
Date: August 1, 1995
Creator: Sather, N.
Partner: UNT Libraries Government Documents Department

The National Facility physics and diagnostics

Description: This paper presents a description of the National Ignition Facility, some of the physics experiments that will be performed on it, and a description of some of the diagnostics needed to complete these experiments. Experiments are presented under the headings of: ignition physics, weapons physics or high-energy-density experimental science, weapons effects, and basic science and inertial fusion energy. The diagnostics discussed are primarily those that will be provided for early operation.
Date: August 6, 1999
Creator: Wootton, A.
Partner: UNT Libraries Government Documents Department

Multilayer Thermionic Refrigeration

Description: A review is presented of our program to construct an efficient solid state refrigerator based on thermionic emission of electrons over periodic barriers in the solid. The experimental program is to construct a simple device with one barrier layer using a three layers: metal-semiconductor-metal. The theoretical program is doing calculations to determine: (i) the optimal layer thickness, and (ii) the thermal conductivity.
Date: August 30, 1999
Creator: Mahan, G. D.
Partner: UNT Libraries Government Documents Department

Industrial applications of high-power copper vapor lasers

Description: A growing appreciation has developed in the last several years for the copper vapor laser because of its utility in ablating difficult materials at high rates. Laser ablation at high rates shows promise for numerous industrial applications such as thin film deposition, precision hole drilling, and machining of ceramics and other refractories.
Date: August 1, 1995
Creator: Warner, B.E.; Boley, C.D.; Chang, J.J.; Dragon, E.P.; Havstad, M.A.; Martinez, M. et al.
Partner: UNT Libraries Government Documents Department

An overview of the US Department of Energy Plant Lifetime Improvement Program

Description: This paper provides a brief summary of the U.S. Department of Energy`s (USDOE`s) cooperative effort with the nuclear industry to develop technology to manage the effects of material degradation in systems, structures and components (SSCs) that impact plant safety or can significantly improve plant performance/economics and to establish and demonstrate the license renewal process. Also included are efforts to reduce decontamination/decommission costs, and reduce the uncertainty in long-term service-life decision making. During 1995, the Plant Lifetime Improvement (PLIM) Program was renamed the Commercial Operating Light Water Reactor (COLWR) Program activities are focused on sustaining the LWR option for domestic electricity generation by supporting operation of existing LWRs as long as they are safe, efficient, and economical. The status of the key projects is discussed in this paper.
Date: August 1, 1995
Creator: Moonka, A.K. & Harrison, D.L.
Partner: UNT Libraries Government Documents Department

International Conference on Climate Change Adaptation Assessments: Conference summary and statement

Description: The International Conference on Climate Change Adaptation Assessments was held in St. Petersburg, Russian Federation, from May 22--25, 1995. Sponsored by the Russian Federal Service for Hydrometeorology and Environmental Monitoring, the US Country Studies Program, and the directorate General for International Cooperation of the Netherlands Government, it was the first international conference focusing exclusively on adaptation to climate change. More than 100 people from 29 countries on five continents participated. The conference primarily addressed measures to anticipate the potential effects of climate change to minimize negative effects and take advantage of any positive effects. The focus was on what governments, institutions, and individuals can do to prepare for climate change. The conference dealt with two major topics: What adaptation options are most effective and efficient in anticipating climate change and what methods should be used to assess the effectiveness and efficiency of adaptation options. Brief summaries are given from the following sessions on agriculture; Water resources; coastal resources; ecosystems and forests; fisheries; human settlements; water and agriculture; and the panel session on international adaptation in national communications and other development plans and needs for technical assistance.
Date: August 1, 1995
Partner: UNT Libraries Government Documents Department

Intramolecular condensation reactions of {alpha}, {omega}- bis(triethoxy-silyl)alkanes. Formation of cyclic disilsesquioxanes

Description: Under acidic sol-gel polymerization conditions, 1,3-bis(triethoxysilyl)-propane (1) and 1,4-bis(triethoxysilyl)butane (2) were shown to preferentially form cyclic disilsesquioxanes 3 and 4 rather than the expected 1,3-propylene- and 1,4-butylene-bridged polysilsesquioxane gels. Formation of 3 and 4 is driven by a combination of an intramolecular cyclization to six and seven membered rings, and a pronounced reduction in reactivity under acidic conditions as a function of increasing degree of condensation. The ease with which these relatively unreactive cyclic monomers and dimers are formed (under acidic conditions) helps to explain the difficulties in forming gels from 1 and 2. The stability of cyclic disilsesquioxanes was confirmed withe the synthesis of 3 and 4 in gram quantities; the cyclic disilsesquioxanes react slowly to give tricyclic dimers containing a thermodynamically stable eight membered siloxane ring. Continued reactions were shown to perserve the cyclic structure, opening up the possibility of utilizing cyclic disilsesquioxanes as sol-gel monomers. Preliminary polymerization studies with these new, carbohydrate-like monomers revealed the formation of network poly(cyclic disilsesquioxanes) under acidic conditions and polymerization with ring-opening under basic conditions.
Date: August 1, 1996
Creator: Loy, D.A.; Carpenter, J.P.; Myers, S.A.; Assink, R.A.; Small, J.H.; Greaves, J. et al.
Partner: UNT Libraries Government Documents Department

Severe accident progression perspectives based on IPE results

Description: Accident progression perspectives were gathered from the level 2 PRA analyses (the analysis of the accident after core damage has occurred involving the containment performance and the radionuclide release from the containment) described in the IPE submittals. Insights related to the containment failure modes, the releases associated with those failure modes, and the factors responsible for the types of containment failures and release sizes reported were obtained. Complete results are discussed in NUREG-1560 and summarized here.
Date: August 1, 1996
Creator: Lehner, J.R.; Lin, C.C.; Pratt, W.T. & Drouin, M.
Partner: UNT Libraries Government Documents Department

The waveform correlation event detection system project: Issues in system refinement, tuning, and operation

Description: The goal of the Waveform Correlation Event Detection System (WCEDS) Project at Sandia Labs has been to develop a prototype of a full-waveform correlation based seismic event detection system which could be used to assess potential usefulness for CTBT monitoring. The current seismic event detection system in use at the IDC is very sophisticated and provides good results but there is still significant room for improvement, particularly in reducing the number of false events (currently being nearly equal to the number of real events). Our first prototype was developed last year and since then we have used it for extensive testing from which we have gained considerable insight. The original prototype was based on a long-period detector designed by Shearer (1994), but it has been heavily modified to address problems encountered in application to a data set from the Incorporated Research Institutes for Seismology (IRIS) broadband global network. Important modifications include capabilities for event masking and iterative event detection, continuous near-real time execution, improved Master Image creation, and individualized station pre-processing. All have been shown to improve bulletin quality. In some cases the system has detected marginal events which may not be detectable by traditional detection systems, but definitive conclusions cannot be made without direct comparisons. For this reason future work will focus on using the system to process GSETT3 data for comparison with current event detection systems at the IDC.
Date: August 1, 1996
Creator: Young, C.J.; Beiriger, J.I.; Harris, J.M.; Moore, S.G.; Trujillo, J.R.; Withers, M.M. et al.
Partner: UNT Libraries Government Documents Department

Transverse multibunch modes for non-rigid bunches, including mode coupling

Description: A method for computing transverse multibunch growth rates and frequency shifts in rings, which has been described previously, is applied to the PEP-II B factory. The method allows multibunch modes with different internal-bunch oscillation modes to couple to one another, similar to single-bunch mode coupling. Including coupling between the multibunch modes gives effects similar to those seen in single-bunch mode coupling. These effects occur at currents that are lower than the single-bunch mode coupling threshold.
Date: August 1, 1995
Creator: Bert, J.S. & Ruth, R.D.
Partner: UNT Libraries Government Documents Department

Off-specular reflectivity study of sputter-deposition of platinum during growth

Description: A series of off-specular diffuse scattering measurements were performed by scanning the detector arm parallel to the sample surface during growth of platinum films on polished silicon substrates. During early stage of growth, we observe a halo of diffuse scattering around the specular reflection which is similar to Henzler`s ring. A model of random islands was developed to explain the halo of diffuse scattering. During late growth, the film surface was consistent with partially self-affine surface.
Date: August 1, 1995
Creator: You, H.; Huang, K.G. & Kampwirth, R.T.
Partner: UNT Libraries Government Documents Department