UT-Battelle

:The measurement of project success in the construction industry has traditionally been grounded in the industry-accepted classic objective success metrics: cost, schedule, performance, and safety. Initial research has indicated that there are more subjective considerations that, while being difficult to quantify, can have an important impact on perceptions of project success. During ongoing project management research, the authors recognized the need for a measurement tool that would account for subjective as well as objective metrics in assessing project success. The tool would have to provide the flexibility necessary to account for the fact that every project is different. The resulting Construction Project Success Survey (CPSS) instrument is designed to investigate how experienced construction project management personnel perceive project success, both objectively and subjectively. The engineering manager can use this tool to identify important success metrics before the start of a project, and to evaluate the level of success achieved at project completion.

Recent experiments (Synakowski et al 2004 Nucl. Fusion 43 1648, Lloyd et al 2004 Plasma Phys. Control. Fusion 46 B477) on the Spherical Tokamak (or Spherical Torus, ST) (Peng 2000 Phys. Plasmas 7 1681) have discovered robust plasma conditions, easing shaping, stability limits, energy confinement, self-driven current and sustainment. This progress has encouraged an update of the plasma conditions and engineering of a Component Test Facility (CTF), (Cheng 1998 Fusion Eng. Des. 38 219) which is a very valuable step in the development of practical fusion energy. The testing conditions in a CTF are characterized by high fusion neutron fluxes Γn ≈ 8.8 × 1013 n s−1 cm−2 ('wall loading' WL ≈ 2 MW m−2), over size-scale >105 cm2 and depth-scale >50 cm, delivering >3 accumulated displacement per atom per year ('neutron fluence' >0.3 MW yr−1 m−2) (Abdou et al 1999 Fusion Technol. 29 1). Such conditions are estimated to be achievable in a CTF with R0 = 1.2 m, A = 1.5, elongation ∼3, Ip ∼ 12 MA, BT ∼ 2.5 T, producing a driven fusion burn using 47 MW of combined neutral beam and RF heating power. A design concept that allows straight-line access via remote handling to all activated fusion core components is developed and presented. The ST CTF will test the lifetime of single-turn, copper alloy centre leg for the toroidal field coil without an induction solenoid and neutron shielding and require physics data on solenoid-free plasma current initiation, ramp-up to and sustainment at multiple megaampere level. A systems code that combines the key required plasma and engineering science conditions of CTF has been prepared and utilized as part of this study. The results show high potential for a family of relatively low cost CTF devices to suit a range of fusion engineering and technology test missions.

Spontaneous agglomeration of engineered nanoparticles (ENPs) is a common problem in cell culture media which can confound interpretation of in vitro nanotoxicity studies. The authors created stable agglomerates of iron oxide nanoparticles (IONPs) in conventional culture medium, which varied in hydrodynamic size (276 nm-1.5 μm) but were composed of identical primary particles with similar surface potentials and protein coatings. Studies using C10 lung epithelial cells show that the dose rate effects of agglomeration can be substantial, varying by over an order of magnitude difference in cellular dose in some cases. Quantification by magnetic particle detection showed that small agglomerates of carboxylated IONPs induced greater cytotoxicity and redox-regulated gene expression when compared with large agglomerates on an equivalent total cellular IONP mass dose basis, whereas agglomerates of amine-modified IONPs failed to induce cytotoxicity or redox-regulated gene expression despite delivery of similar cellular doses. Dosimetry modelling and experimental measurements reveal that on a delivered surface area basis, large and small agglomerates of carboxylated IONPs have similar inherent potency for the generation of ROS, induction of stress-related genes and eventual cytotoxicity. The results suggest that reactive moieties on the agglomerate surface are more efficient in catalysing cellular ROS production than molecules buried within the agglomerate core. Because of the dynamic, size and density-dependent nature of ENP delivery to cells in vitro, the biological consequences of agglomeration are not discernible from static measures of exposure concentration (μg/ml) alone, highlighting the central importance of integrated physical characterisation and quantitative dosimetry for in vitro studies. The combined experimental and computational approach provides a quantitative framework for evaluating relationships between the biocompatibility of nanoparticles and their physical and chemical characteristics.

The droplet interface bilayer (DIB) is a modular technique for assembling planar lipid membranes between water droplets in oil. The DIB method thus provides a unique capability for developing digital, droplet-based membrane platforms for rapid membrane characterization, drug screening and ion channel recordings. This paper demonstrates a new, low-volume microfluidic system that automates droplet generation, sorting, and sequential trapping in designated locations to enable the rapid assembly of arrays of DIBs. The channel layout of the device is guided by an equivalent circuit model, which predicts that a serial arrangement of hydrodynamic DIB traps enables sequential droplet placement and minimizes the hydrodynamic pressure developed across filled traps to prevent squeeze-through of trapped droplets. Furthermore, the incorporation of thin-film electrodes fabricated via evaporation metal deposition onto the glass substrate beneath the channels allows for the first time in situ, simultaneous electrical interrogation of multiple DIBs within a sealed device. Combining electrical measurements with imaging enables measurements of membrane capacitance and resistance and bilayer area, and our data show that DIBs formed in different trap locations within the device exhibit similar sizes and transport properties. Simultaneous, single channel recordings of ion channel gating in multiple membranes are obtained when alamethicin peptides are incorporated into the captured droplets, qualifying the thin-film electrodes as a means for measuring stimuli-responsive functions of membrane-bound biomolecules. This novel microfluidic-electrophysiology platform provides a reproducible, high throughput method for performing electrical measurements to study transmembrane proteins and biomembranes in low-volume, droplet-based membranes.

Abstract Seismic refraction methods are used in environmental and engineering studies to image the shallow subsurface. We present a blind test of inversion and tomographic refraction analysis methods using a synthetic first-arrival-time dataset that was made available to the community in 2010. The data are realistic in terms of the near-surface velocity model, shot-receiver geometry and the data's frequency and added noise. Fourteen estimated models were determined by ten participants using eight different inversion algorithms, with the true model unknown to the participants until it was revealed at a session at the 2011 SAGEEP meeting. The estimated models are generally consistent in terms of their large-scale features, demonstrating the robustness of refraction data inversion in general, and the eight inversion algorithms in particular. When compared to the true model, all of the estimated models contain a smooth expression of its two main features: a large offset in the bedrock and the top of a steeply dipping low-velocity fault zone. The estimated models do not contain a subtle low-velocity zone and other fine-scale features, in accord with conventional wisdom. Together, the results support confidence in the reliability and robustness of modern refraction inversion and tomographic methods.

Abstract Over the past fifteen years, notable progress has been made in the performance of airborne geophysical systems for mapping and detection of unexploded ordnance in terrestrial and shallow marine environments. For magnetometer systems, the most significant improvements include development of boom-mounted platforms, and implementation of higher sample rates, denser magnetometer arrays, and vertical gradient configurations. Nine magnetometer-based systems are described and their performance summarized. In prototype analyses and recent U.S. Department of Defense Environmental Security Technology Certification Program (ESTCP) assessments using new production systems, the best performance has been achieved with a vertical gradient configuration. As effective as magnetometer systems have proven to be at many sites, they are inadequate at sites where basalts and other ferrous geologic formations or soils produce anomalies that approach or exceed those of target ordnance items. Additionally, magnetometer systems are ineffective where detection of non-ferrous ordnance items is of primary concern. We discuss the development of airborne time-domain electromagnetic systems over the past ten years. Overall, improvements in airborne geophysical systems have led to more consistent detection of smaller ordnance. These trends should continue as additional technological advances are made.

International projects are very attractive to companies seeking to expand their business horizons, and collaborative networks of international partners have created new work environments that differ from the conventional business structures of the past. This study provides scholarly research into the risks that inherently affect an international project's success and provides insight into the effective measures that project managers may employ to assist in analyzing and mitigating these multinational risks during the bid and proposal process. A new method of radial risk mapping assists management in graphing their risk findings to aid in their proposal analysis. These graphical representations provide firms seeking international markets with a method for selecting those projects with the least risk, thereby increasing their chances of success and maximum profit.

Abstract In April 2007, Battelle demonstrated two new airborne vertical magnetic gradiometer systems for unexploded ordnance (UXO) mapping and detection at the Former Kirtland Precision Bombing Range, New Mexico. The primary benefit of vertical gradient is that it reduces helicopter noise, improving signal-to-noise by about a factor of 5 relative to the ORAGS-Arrowhead total field system (Gamey et al., 2004). The two systems are called VG-16 and VG-22. VG-22 was designed for high-resolution detection of small ordnance under good field conditions, while VG-16 was designed with a wider swath for better production rates on wide-area assessment surveys or where conditions require slightly higher altitudes. Performance of the systems was assessed in a 500-acre test area in which site conditions were well known from previous surveys. This area was deemed relatively quiet magnetically, and was prepared by an unaffiliated contractor which buried 88 small ordnance items at locations that were unknown to Battelle. This “blind-seeded” area included projectiles as large as 155 mm and as small as 40 mm, as well as mortars. VG-22 data yielded 90% detection and VG-16 data demonstrated 67% detection of the emplaced items. In addition to these individually emplaced items, ten pairs of 60-mm mortars were emplaced to assess sensitivity to closely spaced ordnance. The ability to distinguish these mortars as separate items confirmed expectations based on a published approach. For those 60-mm mortars that are expected to appear as individual anomalies, probability of detection was the same as for widely spaced items.

Chromium has served as an exceptional and necessary elemental component of many industrial processes and consumer products. Its prevalence in the global environment as both a dissolved and wind‐borne constituent has prompted concern during the last several decades due to the large migration potential and biological toxicity of various Cr chemical species. The objective of this study was to develop an improved understanding and predictive capability of the rates and mechanisms of competing geochemical redox and sorption reactions that govern the fate and transport of Cr(III) and C(VI) in heterogeneous subsurface environments. Batch and miscible displacement experiments, coupled with solid‐phase spectroscopy methods, were utilized to quantify the interaction of Cr with subsurface materials acquired from three geographically distinct locations within the continental United States that represented soils from different Department of Energy facilities known to have issues regarding Cr contamination. Soil chemical and mineralogical properties were found to be important factors controlling the mechanisms of Cr–solid phase interactions, with many of the reactive processes being time dependent. Both sorption and redox reactions impacted Cr(III)– and Cr(VI)–solid phase interactions and were modeled as nonlinear, nonequilibrium or equilibrium, reversible or nonreversible reactive processes. The research investigations within this study highlight the environmental significance of Cr speciation and solid‐phase reactivity in heterogeneous subsurface soil systems with contrasting geochemical and mineralogical properties.

Matrix graphite (MG) with incompletely graphitized binder used in high-temperature gas-cooled reactors (HTGRs) is commonly suspected to exhibit lower oxidation resistance in air. In order to reveal the oxidation performance, the oxidation behavior of newly developed A3-3 MG at the temperature range from 500 to 950°C in air was studied and the effect of oxidation on the compressive strength of oxidized MG specimens was characterized. Results show that temperature has a significant influence on the oxidation behavior of MG. The transition temperature between Regimes I and II is ~700°C and the activation energy (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mrow><mml:msub><mml:mrow><mml:mi>E</mml:mi></mml:mrow><mml:mrow><mml:mi>a</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math>) in Regime I is around 185 kJ/mol, a little lower than that of nuclear graphite, which indicates MG is more vulnerable to oxidation. Oxidation at 550°C causes more damage to compressive strength of MG than oxidation at 900°C. Comparing with the strength of pristine MG specimens, the rate of compressive strength loss is 77.3% after oxidation at 550°C and only 12.5% for oxidation at 900°C. Microstructure images of SEM and porosity measurement by Mercury Porosimetry indicate that the significant compressive strength loss of MG oxidized at 550°C may be attributed to both the uniform pore formation throughout the bulk and the preferential oxidation of the binder.

Researchers at the Savannah River Site (SRS) and Oak Ridge National Laboratory (ORNL) examined the performance and stability to irradiation of an improved calix[4]arene-based paraffin extraction solvent consisting of a calix[4]arene chelator, 1-(2,2,3,3-tetrafluoropropoxy)-3-(4-sec-butylphenoxy)-2-propanol (Cs-7SB modifier) and trioctylamine (TOA) for the removal of cesium from high-level waste. As a result of testing performed in 1998, modifications to the solvent system were made to improve chemical stability. The robustness to irradiation of the current calix[4]arene-based solvent system was examined by exposing agitated solvent in contact with aqueous phases representing the composition on the stages of extraction (alkaline waste simulant), scrub (0.05-M nitric acid), and strip (0.001-M nitric acid) to a dose up to 50 Mrad by a 60Co gamma source. The solvent was also agitated for 101 days with high-level liquid waste from the Savannah River Site (SRS) tanks. After irradiation, the concentration of the components in the solvent system and the identification of degradation products were determined primarily using gas chromatography (GC) and high-performance liquid chromatography (HPLC). The expected yearly dose the solvent will receive is 100 krad/year. An approximately 10% concentration drop in trioctylamine was observed at a 2-Mrad dose of gamma radiation, an estimate 20-year radiation dose. At gamma-radiation doses as high as 16 Mrad, or an estimated 160-year-radiation dose, there was not a significant loss of the calix[4]arene chelator (less than 10%), and there was only a minor loss (less than 2%) of Cs-7SB modifier that yields the degradation product 4-sec-butylphenol. Additional testing indicated that this phenol is readily removed by a caustic wash. Distribution coefficients for Cs between the phases (DCs) were also determined using inductively coupled plasma mass spectroscopy (ICP-MS) and gamma-counting methods. Relative to unirradiated solvent, extraction, scrubbing, and stripping performance were not significantly affected by external gamma-radiation doses as high as 8 Mrad, an estimated 80-year dose. These findings indicate that the solvent is stable and retains its expected extraction, scrubbing, and stripping properties after exposure to relatively high-gamma-radiation doses (up to 8 Mrad).

Abstract We have developed a new helicopter-borne transient electromagnetic system, known as ORAGS-TEM, which was designed for the detection of unexploded ordnance (UXO) through very low altitude measurements. This system has already achieved considerable success in demonstrations over prepared test grids and a bombing site at the former Badlands Bombing Range (BBR) in South Dakota. UXO ranging in size from 113 kg (250 lb) bombs to 60 mm illumination shells and 7 cm (2.75 in) rocket components were detected by both magnetometer and transient electromagnetic technologies during these trials, conducted in September, 2002. The signal/noise ratio (SNR) observed in TEM measurements during these trials was high, prompting us to ask, “What degree of UXO discrimination can be achieved through detailed analysis of this airborne TEM dataset?” Given the degree of spatial averaging and sampling limitations imposed by the system's flight height and speed, we felt that a very detailed analysis of the type performed by Pasion and Oldenburg would not be practical. Instead, we developed an improved transient analysis technique based on the Matrix Pencil Method to improve the accuracy of exponential decomposition of the observed transients. Where target SNR values of 10 or higher were present this method yielded repeatable results that reliably distinguished compact, long-time-constant targets such as bombs and artillery shells from short-time-constant targets such as thin-walled scrap from practice bombs. As system sensitivity and resolution continues to improve, we expect that similar target discrimination methods will become standard data analysis tools.

Abstract Airborne geophysical sensor systems using boom-mounted configurations now play an important role in characterizing ordnance-contaminated defense sites. Most of the systems developed to date have been magnetometer systems. These have proven ineffective at sites where basalt or other magnetic geologic units or soils have caused unacceptable noise in the data. Electromagnetic (EM) systems have been developed as an alternative to magnetometer systems for such sites. Recent evaluation of New Mexico field results from the new TEM-8 time-domain EM system has shown successful detection of emplaced blind-seeded ordnance items. Overall, 109 of 110 items were detected, some as small as 81-mm mortars at an area with moderately magnetic geology. The TEM-8 system was also effective in mapping ordnance at a bombing target with severe geologic interference due to basalt, where a previous airborne magnetometer survey proved ineffective. Data and performance metrics for both survey areas are presented and evaluated.

Many specialized applications in near-surface geophysics require greater spatial and amplitude sensitivity than conventional geophysical systems can provide. Recently developed boom-mounted airborne magnetometer and electromagnetic systems are designed to map unexploded ordnance or other small metallic objects over large tracts of government land. These systems operate at altitudes of 1.5–2.0 m to detect ferrous objects with a mass as small as 2 kg. In this low-altitude environment, factors controlling the applicability of a vertical gradient configuration must be reassessed. Our results demonstrate the superiority of measured vertical gradient over calculated gradient (from total field configurations) for data acquired at these low altitudes. We believe the effectiveness is related to reduction of secondary gridding effects associated with several types of positioning errors, and reduction of correlated rotor and compensation noise.

Abstract Sagittaria latifolia plants and soils were sampled at 11 sites on or near the Energy Research and Development Administration's Savannah River Plant near Aiken, South Carolina. Plants and soils were analyzed for radiocesium concentrations. Concentration ratios (CR) were calculated as a relative measure of availability. On the basis of eight sites, which were similar in soil properties, three principal components, extracted from a correlation matrix, explained 80.8% of the total variation in measurements of soil characteristics. Principal component I was directly associated with soil moisture, soil organic matter, extractable potassium, percent very fine sand, and inversely related to percent coarse soil. Component II was related to coarse soil and fine sandy soil. Component III was related to extractable soil potassium and extractable radiocesium. A multiple regression of log (CR) against the principal component scores demonstrated a decrease in the availability of radiocesium to Sagittaria with increasing soil moisture, organic matter, extractable potassium, and percent very fine sand and silt. Availability was greatest on coarse sandy soils. Maximum likelihood factor analysis across all eleven sites, based on a partial correlation matrix adjusted for differences among locations, indicated that, regardless of soil radiocesium concentrations, the availability of radiocesium was directly related to soil particle size (% weight) &gt;0.5 mm and inversely related to particle size (% weight) &lt;0.25 mm.

Abstract A low altitude helicopter magnetic survey for unexploded ordnance in New Mexico revealed several magnetic anomalies that were most likely induced by lightning strikes. Lightning-strike magnetic anomalies are not necessarily rare, but may be spaced so widely as to make their detection unlikely in a ground survey. Detailed examples are not often reported because ground geophysical surveys may not cover enough area to detect one, and traditional airborne surveys, which do cover large areas, are carried out at an altitude and line spacing which does not appropriately define the unusual shape of the lightning strike anomaly. However, very low-level (1–3 m altitude) airborne magnetic surveys have data densities similar to ground geophysical surveys, yet cover much larger areas. Lightning anomalies appear in magnetic data as radial arms emanating from a central strike point. Each arm has distinct positive and negative lobes. Anomaly amplitudes in the New Mexico survey area ranged from roughly −30 to +30 nT/m, and the lightning-strike anomaly density was about one per 20 hectares. This is a conservative estimate, as only the most obvious anomalies were counted. The character of the lightning-induced magnetic anomalies changes with an increase in survey altitude or with wider line spacing, making them less distinct from other types of magnetic anomalies.

Abstract The phenomenon of hormesis has been observed mainly for the response of individual organisms to stress. A reasonable line of inquiry might explore the possibility of observing hormesis at other levels of ecological organization. This initial examination focuses on ecosystem hormesis. Explorations of hormetic responses of ecosystems to stress cannot be made independently of a fundamental concept of ecosystem. The scale‐dependence of ecosystem dynamics also influences whether an ecological disturbance is in reality a stressor. Ecosystem hormesis might be claimed if one or more components of an ecosystem exhibit hormesis. By this definition, ecosystem hormesis would be a trivial extension of hormesis observed for individual organisms. A non‐trivial extension of ecosystem hormesis would include the observation that integrated (i.e., holistic) measures of ecosystem structure or function displayed an hormetic response to an ecological stressor. Several such examples of ecosystem structural and functional hormesis are presented. Key words: hormesisecosystem responseecosystem disturbance Notes The Cadmus Group, Inc., 136 Mitchell Road, Oak Ridge, TN 37830 Phone: (423) 425–0401 Fax: (423) 425–0482 Email: sbartell@cadmusgroup.com

Two new airborne vertical magnetic gradient arrays, which mount directly to a helicopter for operation at 1.5–5m altitude, have recently been tested at an unexploded ordnance (UXO) test site in Ohio. These arrays consist of 16 and 22 cesium vapor magnetometers respectively, configured as 8 and 11 vertical magnetic gradiometers. Results from the test demonstrate significant improvements in performance over previous total field systems.

Arc melted Mo-41%Re has been produced at the Oak Ridge National Laboratory using a manufacturing process that is similar to that used for the production of iridium alloys for the encapsulation of plutonium oxide in the General Purpose Heat Source. This particular alloy of molybdenum and rhenium was selected because it would have about the lowest thermal conductivity while avoiding a composition where processing and use could lead to precipitation of undesirable phases. The Mo-41%Re was rolled into plate and sheet products which were used for characterization and to supply material for research and development relevant to alkali metal thermal to electric conversion (AMTEC) cells. Initial attempts indicated that the arc melted Mo-41%Re is fabricable in similar shapes and geometries required for the AMTEC cell. In addition, it was demonstrated that arc melted Mo-41%Re can be electron beam welded without the porosity normally observed in welded powder metallurgy products. Preliminary assessments of the properties of Mo-41%Re were made to provide recommended data for design purposes. In some cases, the only available data were obtained on powder metallurgy or wrought material or on material with different percentages of rhenium. Experimental data indicate that the electrical resistivity and thermal conductivity of Mo-41%Re are about the same as those of Nb-1Zr, which was the refractory alloy initially considered for this application. The ultimate and yield strengths are substantially greater than those of Nb-1Zr. The oxidation resistance of Mo-41%Re is much better than that of Nb-1Zr for two reasons. Firstly, the oxidation rate is slower for the Mo-41%Re and, secondly, oxidation that does occur is limited to a surface effect and does not reduce the strength and ductility as is observed with Nb-1Zr. Oxidation of Mo-41%Re does cause thinning, and preliminary values of the thinning rates at 800 and 900 °C in a rather high partial pressure of oxygen are provided. This factor needs to be considered in planning production, storage, and ground testing.

Abstract Magnetic and electromagnetic data collected by helicopter boom-mounted systems at three different sites permit direct comparison of the systems as to their suitability for buried ordnance detection, mapping, and discrimination. Airborne boom-mounted magnetic systems are at a more advanced stage of development than their electromagnetic counterpart. However, in basaltic terrain, transient electromagnetic systems have proved capable of detecting buried ordnance, whereas magnetic systems may fail to detect ordnance altogether. Magnetic systems use passive sensors and these can be distributed along the boom structure such that dense data can be collected with sensors spaced 1–2 m apart over a broad swath, up to 12-m wide. The ORAGS-TEM electromagnetic system, having only two receivers, must rely on interleaved flight lines to obtain data of a spatial density approaching that of the airborne magnetic systems. The total magnetic fields from unexploded ordnance decays at 1/R3 for total field and its gradient at 1/R4. This permits adequate signal-to-noise levels to be easily attained for larger ordnance types at survey heights up to seven meters. Active electromagnetic fields decay at between1/R4 and 1/R6, depending on ordnance type and sensor geometry, and this constrains current electromagnetic systems to practical survey altitudes of less than three meters. Tests at the Badlands Bombing Range indicate that, in some circumstances, the signal-to-noise for the airborne electromagnetic system exceeds that of airborne magnetic systems, and even ground electromagnetic systems. Because time must be allowed for transmitter current buildup and decay, ORAGS-TEM is not capable of sampling along line at the same spatial density as can magnetic systems. However, the temporal signal decay permits greater opportunity for ordnance discrimination than magnetic measurements.