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Fast Pyrolysis Oil Stabilization: An Integrated Catalytic and Membrane Approach for Improved Bio-oils (open access)

Fast Pyrolysis Oil Stabilization: An Integrated Catalytic and Membrane Approach for Improved Bio-oils

This University of Massachusetts, Amherst project, "Fast Pyrolysis Oil Stabilization: An Integrated Catalytic and Membrane Approach for Improved Bio-oils" started on 1st February 2009 and finished on August 31st 2011. The project consisted following tasks: Task 1.0: Char Removal by Membrane Separation Technology The presence of char particles in the bio-oil causes problems in storage and end-use. Currently there is no well-established technology to remove char particles less than 10 micron in size. This study focused on the application of a liquid-phase microfiltration process to remove char particles from bio-oil down to slightly sub-micron levels. Tubular ceramic membranes of nominal pore sizes 0.5 and 0.8 µm were employed to carry out the microfiltration, which was conducted in the cross-flow mode at temperatures ranging from 38 to 45 C and at three different trans-membrane pressures varying from 1 to 3 bars. The results demonstrated the removal of the major quantity of char particles with a significant reduction in overall ash content of the bio-oil. The results clearly showed that the cake formation mechanism of fouling is predominant in this process. Task 2.0 Acid Removal by Membrane Separation Technology The feasibility of removing small organic acids from the aqueous fraction of fast …
Date: October 19, 2012
Creator: \Huber, George W.; Upadhye, Aniruddha A.; Ford, David M.; Bhatia, Surita R. & Badger, Phillip C.
System: The UNT Digital Library
Annual report of groundwater monitoring at Centralia, Kansas, in 2009. (open access)

Annual report of groundwater monitoring at Centralia, Kansas, in 2009.

In September 2005, periodic sampling of groundwater was initiated by the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) in the vicinity of a grain storage facility formerly operated by the CCC/USDA at Centralia, Kansas. The sampling at Centralia is being performed on behalf of the CCC/USDA by Argonne National Laboratory, in accord with a monitoring program approved by the Kansas Department of Health and Environment (KDHE). The objective is to monitor levels of carbon tetrachloride contamination identified in the groundwater at Centralia (Argonne 2003, 2004, 2005a). Under the KDHE-approved monitoring plan (Argonne 2005b), the groundwater was sampled twice yearly from September 2005 until September 2007 for analyses for volatile organic compounds (VOCs), as well as measurement of selected geochemical parameters to aid in the evaluation of possible natural contaminant degradation (reductive dechlorination) processes in the subsurface environment. The results from the two-year sampling program demonstrated the presence of carbon tetrachloride contamination at levels exceeding the KDHE Tier 2 risk-based screening level (RBSL) of 5 {micro}g/L for this compound in a localized groundwater plume that has shown little movement. The relative concentrations of chloroform, the primary degradation product of carbon tetrachloride, suggested that some degree of reductive dechlorination …
Date: October 19, 2010
Creator: LaFreniere, L. M.
System: The UNT Digital Library
Imperial Valley Environmental Project: progress report (open access)

Imperial Valley Environmental Project: progress report

Progress is reported in six areas of research: air quality, water quality, ecosystem quality, subsidence and seismicity, socioeconomic effects, and integrated assessment. A major goal of the air quality element is to evaluate the rate of emission of H/sub 2/S, CO/sub 2/, H/sub 2/, N/sub 2/, CH/sub 4/, and C/sub 2/H/sub 6/ from the operation of the geothermal loop experimental facility at Niland. Concentrations of H/sub 2/S were found to vary between 1500 to 4900 ppM by volume at the Niland facility. To distinguish between geothermal fluids and other waters, extensive sampling networks were established. A major accomplishment was the installation of a high-resolution subsidence-detection network in the Salton Sea geothermal field area, centered on the test facility at Niland. A major effort went into establishing a background of data needed for subsequent impact assessments related to socioeconomic issues raised by geothermal developments. Underway are a set of geothermal energy scenarios that include power development schedules, technology characterizations, and considerations of power-plant-siting criteria. A Gaussian air-pollution model was modified for use in preliminary air-quality assessments. A crop-growth model was developed to evaluate impacts of gases released from geothermal operations on various agricultural crops. Work is also reported on the legal …
Date: October 19, 1977
Creator: Phelps, Paul L. & Anspaugh, Lynn R.
System: The UNT Digital Library
Use of the ARM Measurement of Spectral Zenith Radiance For Better Understanding Of 3D Cloud-Radiation Processes and Aerosol-Cloud Interaction (open access)

Use of the ARM Measurement of Spectral Zenith Radiance For Better Understanding Of 3D Cloud-Radiation Processes and Aerosol-Cloud Interaction

Our proposal focuses on cloud-radiation processes in a general 3D cloud situation, with particular emphasis on cloud optical depth and effective particle size. We also focus on zenith radiance measurements, both active and passive. The proposal has three main parts. Part One exploits the “solar-background” mode of ARM lidars to allow them to retrieve cloud optical depth not just for thin clouds but for all clouds. This also enables the study of aerosol cloud interactions with a single instrument. Part Two exploits the large number of new wavelengths offered by ARM’s zenith-pointing ShortWave Spectrometer (SWS), especially during CLASIC, to develop better retrievals not only of cloud optical depth but also of cloud particle size. We also propose to take advantage of the SWS’ 1 Hz sampling to study the “twilight zone” around clouds where strong aerosol-cloud interactions are taking place. Part Three involves continuing our cloud optical depth and cloud fraction retrieval research with ARM’s 2NFOV instrument by, first, analyzing its data from the AMF-COPS/CLOWD deployment, and second, making our algorithms part of ARM’s operational data processing.
Date: October 19, 2010
Creator: Chiu, D. Jui-Yuan
System: The UNT Digital Library
Incorporation of NREL Solar Advisor Model Photovoltaic Capabilities with GridLAB-D (open access)

Incorporation of NREL Solar Advisor Model Photovoltaic Capabilities with GridLAB-D

This report provides a summary of the work updating the photovoltaic model inside GridLAB-D. The National Renewable Energy Laboratory Solar Advisor Model (SAM) was utilized as a basis for algorithms and validation of the new implementation. Subsequent testing revealed that the two implementations are nearly identical in both solar impacts and power output levels. This synergized model aides the system-level impact studies of GridLAB-D, but also allows more specific details of a particular site to be explored via the SAM software.
Date: October 19, 2012
Creator: Tuffner, Francis K.; Hammerstrom, Janelle L. & Singh, Ruchi
System: The UNT Digital Library
Boiling of Freon-114 in a Three-Foot Straight Tube Evaporator (open access)

Boiling of Freon-114 in a Three-Foot Straight Tube Evaporator

Introduction: this report covers two series of tests run on a Freon evaporator containing a vertical copper tube having an outside diameter of 7/8 of an inch, heated externally for a length of 35 inches by steam condensing in a concentric jacket.
Date: October 19, 1961
Creator: Allen, Charles F.
System: The UNT Digital Library
Measurement of heat from the graphite in a dummy-charged KER loop (open access)

Measurement of heat from the graphite in a dummy-charged KER loop

None
Date: October 19, 1959
Creator: Kratzer, W. K.
System: The UNT Digital Library
Demonstration of in-tank sludge processing: Part 2, Effect of processing on radionuclides (open access)

Demonstration of in-tank sludge processing: Part 2, Effect of processing on radionuclides

The scope and cost of the Defense Waste Processing Facility have been significantly reduced by adding in-tank sludge processing to the process flowsheet. A demonstration of in-tank processing was recently completed and the achievement of the major goals described in a previous memo. This memo describes the effect of in-tank sludge processing on the radionuclides in the waste. This memo will also identify those areas that will require further work both before and during the next scheduled in-tank sludge processing batch.
Date: October 19, 1983
Creator: Eibling, R. E. & Hamm, B. A.
System: The UNT Digital Library
Hanford works monthly report, September 1951 (open access)

Hanford works monthly report, September 1951

This is a progress report of the production reactors on the Hanford Reservation for the month of September 1951. This report takes each division (e.g., manufacturing, medical, accounting, occupational safety, security, reactor operations, etc.) of the site and summarizes its accomplishments and employee relations for that month.
Date: October 19, 1951
Creator: Prout, G. R.
System: The UNT Digital Library
Plutonium, neptunium and americium waste tank inventories (open access)

Plutonium, neptunium and americium waste tank inventories

None
Date: October 19, 1964
Creator: Warren, J. H.
System: The UNT Digital Library
Technical criteria and bases for a zirconium-tubed K Reactor (open access)

Technical criteria and bases for a zirconium-tubed K Reactor

The criteria contained in this report have been established to provide the technical bases for the design modifications involved in the K-Reactor tube replacement. The ultimate intent of these criteria is to provide the basic technical data and concepts to assure: technical feasibility and operability of the reactor system as modified; operation of the reactor and its services to minimize nuclear and radiation hazards; and appropriate lifetime of the reactor and its service facilities as modified. The criteria are appropriately broad and may not contain all the data necessary to accomplish detail design. The information contained herein shall serve as a basis for evaluation and approval of all portions of the modification relating to the process as indicated in the above three points.
Date: October 19, 1962
Creator: Curtiss, D. H.
System: The UNT Digital Library
Radiation Research Symposium: Chemistry and Biology of Radical-mediated Deoxyribose Oxidation in DNA (open access)

Radiation Research Symposium: Chemistry and Biology of Radical-mediated Deoxyribose Oxidation in DNA

The $3000 of funding provided by this grant supported a well-attended (150 people) symposium at the annual Radiation Research Society meeting in Denver, Colorado, on October 19, 2005. The symposium was entitled, ''Chemistry and Biology of Radical-mediated Deoxyribose Oxidation in DNA'', and it focused on the chemistry of damage to deoxyribose caused by radiation and other oxidants, and the role of this chemistry in the biological consequences and responses of cells to chemical and physical insults. The talks highlighted the emerging evidence for a major role for deoxyribose oxidation in the toxic effects of ionizing radiation.
Date: October 19, 2005
Creator: Dedon, Peter
System: The UNT Digital Library
Gyrokinetic Stability Studies of the Microtearing Mode in the National Spherical Torus Experiment H-mode (open access)

Gyrokinetic Stability Studies of the Microtearing Mode in the National Spherical Torus Experiment H-mode

Insight into plasma microturbulence and transport is being sought using linear simulations of drift waves on the National Spherical Torus Experiment (NSTX), following a study of drift wave modes on the Alcator C-Mod Tokamak. Microturbulence is likely generated by instabilities of drift waves, which cause transport of heat and particles. Understanding this transport is important because the containment of heat and particles is required for the achievement of practical nuclear fusion. Microtearing modes may cause high heat transport through high electron thermal conductivity. It is hoped that microtearing will be stable along with good electron transport in the proposed low collisionality International Thermonuclear Experimental Reactor (ITER). Stability of the microtearing mode is investigated for conditions at mid-radius in a high density NSTX high performance (H-mode) plasma, which is compared to the proposed ITER plasmas. The microtearing mode is driven by the electron temperature gradient, and believed to be mediated by ion collisions and magnetic shear. Calculations are based on input files produced by TRXPL following TRANSP (a time-dependent transport analysis code) analysis. The variability of unstable mode growth rates is examined as a function of ion and electron collisionalities using the parallel gyrokinetic computational code GS2. Results show the microtearing …
Date: October 19, 2005
Creator: Baumgaertel J.A., Redi M.H., Budny R.V., Rewoldt G., Dorland W.
System: The UNT Digital Library
Waste Package Corrosion Studies Using Small Mockup Experiments (open access)

Waste Package Corrosion Studies Using Small Mockup Experiments

The corrosion of spent nuclear fuel and subsequent mobilization of radionuclides is of great concern in a geologic repository, particularly if conditions are oxidizing. Corroding A516 steel may offset these transport processes within the proposed waste packages at the Yucca Mountain Repository (YMR) by retaining radionuclides, creating locally reducing conditions, and reducing porosity. Ferrous iron, Fe{sup 2+}, has been shown to reduce UO{sub 2}{sup 2+} to UO{sub 2(s)} [1], and some ferrous iron-bearing ion-exchange materials adsorb radionuclides and heavy metals [2]. Of particular interest is magnetite, a potential corrosion product that has been shown to remove TcO{sub 4}{sup -} from solution [3]. Furthermore, if Fe{sup 2+} minerals, rather than fully oxidized minerals such as goethite, are produced during corrosion, then locally reducing conditions may be present. High electron availability leads to the reduction and subsequent immobilization of problematic dissolved species such as TcO{sub 4}{sup -}, NpO{sub 2}{sup +}, and UO{sub 2}{sup 2+} and can also inhibit corrosion of spent nuclear fuel. Finally, because the molar volume of iron material increases during corrosion due to oxygen and water incorporation, pore space may be significantly reduced over long time periods. The more water is occluded, the bulkier the corrosion products, and the …
Date: October 19, 2005
Creator: Anderson, B. E.; Helean, K. B.; Bryan, C. R.; Brady, P. V. & Ewing, R. C.
System: The UNT Digital Library
The BlueGene/L Supercomputer and Quantum ChromoDynamics (open access)

The BlueGene/L Supercomputer and Quantum ChromoDynamics

In summary our update contains: (1) Perfect speedup sustaining 19.3% of peak for the Wilson D D-slash Dirac operator. (2) Measurements of the full Conjugate Gradient (CG) inverter that inverts the Dirac operator. The CG inverter contains two global sums over the entire machine. Nevertheless, our measurements retain perfect speedup scaling demonstrating the robustness of our methods. (3) We ran on the largest BG/L system, the LLNL 64 rack BG/L supercomputer, and obtained a sustained speed of 59.1 TFlops. Furthermore, the speedup scaling of the Dirac operator and of the CG inverter are perfect all the way up to the full size of the machine, 131,072 cores (please see Figure II). The local lattice is rather small (4 x 4 x 4 x 16) while the total lattice has been a lattice QCD vision for thermodynamic studies (a total of 128 x 128 x 256 x 32 lattice sites). This speed is about five times larger compared to the speed we quoted in our submission. As we have pointed out in our paper QCD is notoriously sensitive to network and memory latencies, has a relatively high communication to computation ratio which can not be overlapped in BGL in virtual node …
Date: October 19, 2006
Creator: Vranas, P. & Soltz, R.
System: The UNT Digital Library
Alpha Channeling in Mirror Machines (open access)

Alpha Channeling in Mirror Machines

Because of their engineering simplicity, high-β, and steady-state operation, mirror machines and related open-trap machines such as gas dynamic traps, are an attractive concept for achieving controlled nuclear fusion. In these open-trap machines, the confinement occurs by means of magnetic mirroring, without the magnetic field lines closing upon themselves within the region of particle confinement. Unfortunately, these concepts have not achieved to date very spectacular laboratory results, and their reactor prospects are dimmed by the prospect of a low Q-factor, the ratio of fusion power produced to auxiliary power. Nonetheless, because of its engineering promise, over the years numerous improvements have been proposed to enhance the reactor prospects of mirror fusion, such as tandem designs, end-plugging, and electric potential barriers.
Date: October 19, 2005
Creator: Fisch, N. J.
System: The UNT Digital Library
Observations of the Behavior and Distribution of Fish in Relation to the Columbia River Navigation Channel and Channel Maintenance Activities (open access)

Observations of the Behavior and Distribution of Fish in Relation to the Columbia River Navigation Channel and Channel Maintenance Activities

This report is a compilation of 7 studies conducted for the U.S. Army Corps of Engineers between 1995 and 1998 which used hydroacoustic methods to study the behavior of migrating salmon in response to navigation channel maintenance activities in the lower Columbia River near river mile 45. Differences between daytime and nighttime behavior and fish densities were noted. Comparisons were made of fish distribution across the river (in the channel, channel margin or near shore) and fish depth upstream and downstream of dikes, dredges, and pile driving areas.
Date: October 19, 2001
Creator: Carlson, Thomas J.; Ploskey, Gene R.; Johnson, R. L.; Mueller, Robert P.; Weiland, Mark A. & Johnson, P. N.
System: The UNT Digital Library
RESULTS FOR THE SECOND QUARTER 2009 TANK 50 WAC SLURRY SAMPLE CHEMICAL CONTAMINANT RESULTS (open access)

RESULTS FOR THE SECOND QUARTER 2009 TANK 50 WAC SLURRY SAMPLE CHEMICAL CONTAMINANT RESULTS

None
Date: October 19, 2009
Creator: Reigel, M.; Diprete, C. & Bibler, N.
System: The UNT Digital Library
Mechanical Properties of Blair Dolomite (open access)

Mechanical Properties of Blair Dolomite

Pressure-volume, uniaxial stress loading to failure, uniaxial strain, and acoustic velocity determinations were made on Blair dolomite at confining pressures ranging to 3.5 GPa (Pa = Paschals where 10/sup 5/ Pa = 1 bar or 0.1 GPa = 1 kbar). The bulk modulus K, rapidly rises from an initial 10.4 GPa (at atmospheric pressure) to 102.0 GPa at 1 GPa pressure. At higher pressures, K remains essentially constant (110 GPa). The maximum volume change on loading is 3.9% at 3.5 GPa; the unloading closely follows the loading path. Comparison of uninxial stress tests in compression to 0.7 GPa and extension to 2.1 GPa confining pressure demonstrates that the characteristic shear stress at failure as well as the transition from brittle fracture to ductile flow is strongly dependent upon both the value of the intermediate principal stress sigma /sub 2/ and the rate of strain. The onset of dilatancy as determined in uniaxial compression occurs at about two-thirds of the failure stress. The uniaxial strain loading path is well below the failure envelope in compression. In uniaxial stress loading (compression), Young' s modulus (E) and shear modulus ( mu ) are demonstrated to be very sensitive to both confining pressure and …
Date: October 19, 1973
Creator: Heard, H. C.; Duba, A.; Abey, A. E. & Schock, R. N.
System: The UNT Digital Library
FREQUENCY RESPONSE ANALYSIS OF HRT MOCKUP PRESSURIZER-LEVEL CONTROL LOOP (open access)

FREQUENCY RESPONSE ANALYSIS OF HRT MOCKUP PRESSURIZER-LEVEL CONTROL LOOP

None
Date: October 19, 1956
Creator: Gelman, R. & Robertson, C.S. Jr.
System: The UNT Digital Library
New transient surface-current sensor and recorder (open access)

New transient surface-current sensor and recorder

It was demonstrated that a transient surface-current pulse can be sensed and recorded by a graded-Hc film, a magnetic film with the coercive force Hc varying along the length of the film. Information on the magnitude of the current can be obtained by comparing the domain-wall location with the distribution of Hc value along the film. The transient characteristic of the current pulse can be deduced from the V-shaped configuration of the domain wall. (auth)
Date: October 19, 1973
Creator: Hsieh, E. J. & Vindelov, K. E.
System: The UNT Digital Library
The Response Time of Small Pitot Tubes (open access)

The Response Time of Small Pitot Tubes

None
Date: October 19, 1953
Creator: Weissberg, H. L.
System: The UNT Digital Library
REACTION RATE OF SOLID SODIUM WITH AIR (open access)

REACTION RATE OF SOLID SODIUM WITH AIR

None
Date: October 19, 1953
Creator: Howland, W.H. & Epstein, L.F.
System: The UNT Digital Library
STUDIES OF FLOW DISTRIBUTION IN THE CORE OF A QUARTER-SCALE FLOW MODEL OF THE PWR REACTOR (open access)

STUDIES OF FLOW DISTRIBUTION IN THE CORE OF A QUARTER-SCALE FLOW MODEL OF THE PWR REACTOR

None
Date: October 19, 1956
Creator: Hazard, H.R. & Allen, J.M.
System: The UNT Digital Library