Compare results from state-of-the-art 3D radiative transfer techniques on a variety of input cloud fields with a wide degree of complexity. The goal of this proposal is to compare results from state-of-the-art 3D radiative transfer techniques on a variety of input cloud fields with a wide degree of complexity. This effort will complement ongoing cloud-related efforts of the GCSS working groups, and DoE-ARM Single Column Modeling and Cloud working groups. The intercomparison will be beneficial in delineating the limits and merits of the various approaches currently used to treat 3D radiative transfer theory and will create a broader consensus on what are the most serious remote sensing errors due to 3D effects. Realistic cloud water distributions used as input for many of the experiments will come directly from the ARM archive or from ARM-related modeling activities (such as those in progress as part of GCSS).

Fiscal Year 2002 is the second year of a five-year commitment by the U.S. Department of Energy, National Nuclear Security Administration (NNSA) to invest in development of new and state-of-the-art technologies for the Aerial Measuring Systems (AMS) project. In 2000, NNSA committed to two million dollars for AMS Technical Integration (TI) for each of five years. The tragedy of September 11, 2001, profoundly influenced the program. NNSA redirected people and funding resources at the Remote Sensing Laboratory (RSL) to more immediate needs. Funds intended for AMS TI were redirected to NNSA's new posture of leaning further forward throughout. AMS TI was brought to a complete halt on December 10, 2001. Then on April 30, 2002, NNSA Headquarters allowed the restart of AMS TI at the reduced level of $840,000. The year's events resulted in a slow beginning of several projects, some of which were resumed only a few weeks before the AMS TI Symposium held at RSL on July 30.

A series of dissolution and characterization studies has been performed to determine if FB-Line residues stored in desicooler containers will dissolve using a modified H-Canyon processing flowsheet. Samples of desicooler materials were used to evaluate dissolving characteristics in the low-molar nitric acid solutions used in H-Canyon dissolvers. The selection for the H-Canyon dissolution of desicooler residues was based on their high-enriched uranium content and trace levels of plutonium. Test results showed that almost all of the enriched uranium will dissolve from the desicooler materials after extended boiling in one molar nitric acid solutions. The residue that contained uranium after completion of the extended boiling cycle consisted of brown solids that had agglomerated into large pieces and were floating on top of the dissolver solution. Addition of tenth molar fluoride to a three molar nitric acid solution containing boron did not dissolve remaining uranium from the brown solids. Only after boiling in an eight molar nitric acid-tenth molar fluoride solution without boron did remaining uranium and aluminum dissolve from the brown solids. The amount of uranium associated with brown solids would be approximately 1.4 percent of the total uranium content of the desicooler materials. The brown solids that remain in the …

The goal of the work was to develop and demonstrate computing based modeling and control methodologies that will facilitate integrated operations on the continuous pulp digester. The technical work required to achieve these goals included development of efficient methods for soft-sensing using fundamental models, integration of fault monitoring and control algorithms, and the development of computationally feasible formulations of model predictive control for profile management in the digester. The developed operational methodology for digester grade transition control was benchmarked against an industrial design in cooperation with our collaborators at Weyerhaeuser and Westvaco.

High gradients in radio-frequency (RF) driven accelerators require short wavelengths that have the concomitant requirements of small feature size and high tolerances, 1-2 {micro}m for millimeter wavelengths. Precision metal-forming stampling has the promise of meeting those tolerances with high production rates. This STI will evaluate that promise.

OAK - B135 This project final report summarizes modeling research conducted in the U.S. Department of Energy (DOE), Low Dose Radiation Research Program at the Lovelace Respiratory Research Institute from October 1998 through June 2003. The modeling research described involves critically evaluating the validity of the linear nonthreshold (LNT) risk model as it relates to stochastic effects induced in cells by low doses of ionizing radiation and genotoxic chemicals. The LNT model plays a central role in low-dose risk assessment for humans. With the LNT model, any radiation (or genotoxic chemical) exposure is assumed to increase one¡¯s risk of cancer. Based on the LNT model, others have predicted tens of thousands of cancer deaths related to environmental exposure to radioactive material from nuclear accidents (e.g., Chernobyl) and fallout from nuclear weapons testing. Our research has focused on developing biologically based models that explain the shape of dose-response curves for low-dose radiation and genotoxic chemical-induced stochastic effects in cells. Understanding the shape of the dose-response curve for radiation and genotoxic chemical-induced stochastic effects in cells helps to better understand the shape of the dose-response curve for cancer induction in humans. We have used a modeling approach that facilitated model revisions over …

The Savannah River Site's KAMS facility was designed for the receipt and storage of incoming SNM shipments. MC and A requires confirmation and verification on these items. These items normally arrive packaged in a 9975 container. An Ortec digiDART(tm) coupled to a nominally 2x2 NaI detector is generally used for confirmation measurements. The KAMS facility has a custom designed Neutron Multiplicity Counter (NMC) and a Gamma Isotopic System (GIS) to support verification measurements. The items contain a whole host of materials from Pu metal to mixed Pu/EU and from items relativity free from impurities to items containing significant amounts of impurities as they relate to NMC assay. The 9975 container itself has proved to be a challenge for NDA work as it contains at least 0.5 inches of heavy metal shielding as well as hydrogenous materials. Measurement issues will be addressed in this paper as they apply to the unique application posed by the KAMS environment. These include the 9975 shipping container, confirmatory Measurement Control Program (MCP), Shipper-Receiver reconciliations, and confirmatory receipts measurements vs. timeliness.

Auger recombination in p-type GaSb, InAs and their alloys is enhanced due to the proximity of the bandgap energy and the energy separation to the spin split-off valence band. This can affect the device performance even at moderate doping concentration. They report electron lifetime measurements in a p-type 0.54-eV GaInAsSb alloy, commonly used in a variety of infrared devices. They have studied a series of double-capped heterostructures with varied thicknesses and doping levels, grown by organometallic vapor phase epitaxy on GaSb substrates. The Auger coefficient value of 2.3 x 10{sup -28} cm{sup 6}/s is determined by analyzing the photoluminescence decay constants with a systematic separation of different recombination mechanisms.

Mercuric iodide is a high-density, high-Z semiconducting material useful for gamma ray detection. This makes it convertible to a thermal neutron detector by covering it with a boron rich material and detecting the 478 keV gamma rays resulting from the {sup 10}B(n, {alpha}){sup 7}Li* reaction. However, the 374 barn thermal capture cross section of {sup nat}Hg, makes the detector itself an attractive absorber, and this has been exploited previously. Since previous work indicates that there are no low-energy gamma rays emitted in coincidence with the 368 keV capture gamma from the dominant {sup 199}Hg(n, {gamma}){sup 200}Hg reaction, only the 368 keV capture gamma is seen with any efficiency a relatively thin (few mm) detector. In this paper we report preliminary measurements of neutrons via capture reactions in a bare mercuric iodide crystal and a crystal covered in {sup 10}B-loaded epoxy. The covered detector is an improvement over the bare detector because the presence of both the 478 and 368 keV gamma rays removes the ambiguity associated with the observation of only one of them. Pulse height spectra, obtained with and without lead and cadmium absorbers, showed the expected gamma rays and demonstrated that they were caused by neutrons.

Biosurfactants enhance hydrocarbon biodegradation by increasing apparent aqueous solubility or affecting the association of the cell with poorly soluble hydrocarbon. Here, we show that a lipopeptide biosurfactant produced by Bacillus mojavensis strain JF-2 mobilized substantial amounts of residual hydrocarbon from sand-packed columns when a viscosifying agent and a low molecular weight alcohol were present. The amount of residual hydrocarbon mobilized depended on the biosurfactant concentration. One pore volume of cell-free culture fluid with 900 mg/l of the biosurfactant, 10 mM 2,3-butanediol and 1000 mg/l of partially hydrolyzed polyacrylamide polymer mobilized 82% of the residual hydrocarbon. Consistent with the high residual oil recoveries, we found that the bio-surfactant lowered the interfacial tension (IFT) between oil and water by nearly 2 orders of magnitude compared to typical IFT values of 28-29 mN/m. Increasing the salinity increased the IFT with or without 2,3-butanediol present. The lowest interfacial tension observed was 0.1 mN/m. The lipopeptide biosurfactant system may be effective in removing hydrocarbon contamination sources in soils and aquifers and for the recovery of entrapped oil from low production oil reservoirs. Previously, we reported that Proteose peptone was necessary for anaerobic growth and biosurfactant production by B. mojavensis JF-2. The data gathered from crude …

An investigation with the objective of improving n-type ohmic contacts to GaSb-based devices is described. This study involves a series of n-GaInAsSb and n-GaSb samples with varying doping, grown on both n-GaSb and semi-insulating GaAs substrates. These samples were fabricated into mesa-etched TLM structures, and the specific contact resistivity and sheet resistance of these layers as a function of majority electron concentration were measured. Extremely low specific contact resistivities of about 2 x 10{sup -6} {Omega}-cm{sup 2} and sheet resistances of about 4 {Omega}/{open_square} are found for n-type GaInAsSb doped at about 3 x 10{sup 18} cm{sup -3}.

Most approaches that have been proposed for the remediation of groundwater contaminated with carbon tetrachloride (CCl{sub 4}) produce chloroform (CHCl{sub 3}) as the major product and methylene chloride (CH{sub 2}Cl{sub 2}) as a minor product. Both of these products are nearly as persistent and problematic as the parent compound, but competing reaction pathways produce the more desirable products carbon monoxide (CO) and/or formate (HCOO{sup -}). Results scattered throughout the chemical and environmental engineering literature show that the branching between these reaction pathways is highly variable, but the controlling factors have not been identified. If we understood the fundamental chemistry that controls the branching among these, and related, product-formation pathways, we could improve the applicability of a host of remediation technologies (both chemical and biological) to the large plumes of CCl{sub 4} that contaminate DOE sites across the country. This project will provide the first complete characterization of the mechanisms and kinetics of competing degradation reactions of CCl{sub 4} through laboratory experiments in simple model systems closely coordinated with theoretical modeling studies. The results provide strategies for maximizing the yield of desirable products from CCl{sub 4} degradation, and the most promising of these will be tested in column model systems using …

This Streamlined Approach for Environmental Restoration (SAFER) plan was prepared as a characterization and closure report for Corrective Action Unit (CAU) 357, Mud Pits and Waste Dump, in accordance with the Federal Facility Agreement and Consent Order. The CAU consists of 14 Corrective Action Sites (CASs) located in Areas 1, 4, 7, 8, 10, and 25 of the Nevada Test Site (NTS). All of the CASs are found within Yucca Flat except CAS 25-15-01 (Waste Dump). Corrective Action Site 25-15-01 is found in Area 25 in Jackass Flat. Of the 14 CASs in CAU 357, 11 are mud pits, suspected mud pits, or mud processing-related sites, which are by-products of drilling activities in support of the underground nuclear weapons testing done on the NTS. Of the remaining CASs, one CAS is a waste dump, one CAS contains scattered lead bricks, and one CAS has a building associated with Project 31.2. All 14 of the CASs are inactive and abandoned. Clean closure with no further action of CAU 357 will be completed if no contaminants are detected above preliminary action levels. A closure report will be prepared and submitted to the Nevada Division of Environmental Protection for review and approval upon …

This report summarizes research conducted in 2001 and 2002 under the above grant entitled " All Not Fit to Breed: Survivors of America's First Eugenics Movement"

Tier 2 regulations issued by the U.S. Environmental Protection Agency (EPA) require a substantial reduction in the sulfur content of gasoline. Similar regulations have been enacted for the sulfur level in on-road diesel and recently off-road diesel. The removal of this sulfur with existing and installed technology faces technical and economic challenges. These challenges created the opportunity for new emerging technologies. Research Triangle Institute (RTI) with subcontract support from Kellogg Brown & Root, Inc., (KBR) used this opportunity to develop RTI's transport reactor naphtha desulfurization (TReND) process. Starting with a simple conceptual process design and some laboratory results that showed promise, RTI initiated an accelerated research program for sorbent development, process development, and marketing and commercialization. Sorbent development has resulted in the identification of an active and attrition resistant sorbent that has been prepared in commercial equipment in 100 lb batches. Process development has demonstrated both the sulfur removal performance and regeneration potential of this sorbent. Process development has scaled up testing from small laboratory to pilot plant transport reactor testing. Testing in the transport reactor pilot plant has demonstrated the attrition resistance, selective sulfur removal activity, and regeneration activity of this sorbent material. Marketing and commercialization activities have shown …

Over 160 acres (64.8 ha) of tree seedlings have been planted in eastern and western Kentucky that depict a mixed stand similar to the native vegetation of the area. All these sites have been assessed and various instrumentation is or is planned for installation to monitor environmental conditions and changes on the areas. The environmental conditions include temperature, aspect, slope, rainfall, and other treatment or condition factors.

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Uranium contamination of the subsurface has remained a persistent problem plaguing remedial design at sites across the U.S. that were involved with production, handling, storage, milling, and reprocessing of fissile uranium for both civilian and defense related purposes. Remediation efforts to date have relied upon excavation, pump-and-treat, or passive remediation barriers (PRB's) to remove or attenuate uranium mobility. Documented cases convincingly demonstrate that excavation and pump-and-treat methods are ineffective for a number of highly contaminated sites. There is growing concern that use of conventional PRB's, such as zero-valent iron, are a temporary solution to a problem that will persist for thousands of years. Alternatives to the standard treatment methods are therefore warranted. The core objective of our research is to demonstrate that a phosphorus amendment strategy will result in a reduction of dissolved uranium to below the proposed drinking water standard. Our hypothesis is that long-chain polyphosphate compounds forestall precipitation of sparingly soluble uranyl phosphate compounds, which is key to preventing fouling of wells at the point of injection. Our other fundamental objective is to synthesize and correctly characterize the uranyl phosphate phases that form in the geochemical conditions under consideration. This report summarizes work conducted at the University of …

The two-modulator generalized ellipsometer (2-MGE) is an instrument that measures the change of light polarization upon interacting with a sample. The 2-MGE can operate in either reflection or transmission. In reflection, it acts as a generalized ellipsometer, measuring the standard ellipsometry parameters, as well as the cross-polarization parameters. In transmission, it measures all parameters associated with a general diattenuation and retarder. In this CRADA, Hinds and ORNL have explored the commercial possibilities of the 2-MGE. This exploration has taken two primary paths. First, prototypes were built at both ORNL and Hinds. Second, various scientific applications were explored, including characterization of Polaroid-like materials and various materials under electric field. The main purpose of this CRADA was to develop the two-modulator generalized ellipsometer (2-MGE) into a commercial product. The 2-MGE is an ORNL patented technology (U. S. Patent No. 5956147 (1999)). Associated with the 2-MGE is the computer program EllipsCalc, which is used to simulate spectroscopic ellipsometry data in order to determine useful parameters, such as film thickness, surface roughness, interface thickness, and spectroscopic refractive indices, from the 2-MGE data. To this end, the CRADA had several objectives contained in two phases.

The overarching goal of the proposed research is to develop a comprehensive data and mechanistic knowledge base with respect to the binding and sequestration reactions of organic DNAPL components and heavy metals with different types of soil matrices. A principal ultimate use of this knowledge and information base will be its application as a platform for designing specifically engineered natural geosorbents (ENGs) capable of in situ long-term immobilization of non-aqueous phase organic liquids and heavy metals at contaminated DOE sites and facilities. The sorption and sequestration performance of ENGs for DNAPLs and heavy metals will be monitored and evaluated by measuring their environmental mobility (desorption and leaching) and bioavailability (toxicity and bioaccumulation) to indicator organisms. Appropriate field tests will be designed to demonstrate the efficacy of in-situ immobilization and inactivation of DNAPLs and heavy metals using the engineered natural geosorbents .

The objectives of this project are (a) to synthesize new ionic liquids tailored for the extractive separation of Cs + and Sr 2+; (b) to select optimum macrocyclic extractants through studies of complexation of fission products with macrocyclic extractants and transport in new extraction systems based on ionic liquids; (c) to develop efficient processes to recycle ionic liquids and crown ethers; and (d) to investigate chemical stabilities of ionic liquids under strong acid, strong base, and high-level-radiation conditions.