Large temporal variations of energetic electron intensities at mid-latitudes in the outer radiation zone Progress report

Variations of electron flux density observations by Explorer 12 and 1

Catalysts for ultrahigh current density oxygen cathodes for space fuel cell applications

The objective of this research was to identify promising electrocatalyst/support systems for the oxygen cathode in alkaline fuel cells operating at relatively high temperatures, O2 pressures and current densities. A number of materials were prepared, including Pb-Ru and Pb-Ir pyrochlores, RuO2 and Pt-doped RuO2, and lithiated NiO. Several of these were prepared using techniques that had not been previously used to prepare them. Particularly interesting is the use of the alkaline solution technique to prepare the Pt-doped Pb-Ru pyrochlore in high area form. Well-crystallized Pb(2)Ru(2)O(7-y) was used to fabricate high performance O2 cathodes with relatively good stability in room temperature KOH. This material was also found to be stable over a useful potential range at approximately 140 C in concentrated KOH. Other pyrochlores were found to be either unstable (amorphous samples) or the fabrication of the gas-fed electrodes could not be fully optimized during this project period. Future work may be directed at this problem. High area platinum supported on conductive metal oxide supports produced mixed results: small improvements in O2 reduction performance for Pb(2)Ru(2)O(7-y) but a large improvement for Li-doped NiO at room temperature. Nearly reversible behavior was observed for the O2/OH couple for Li-doped NiO at approximately 200 C

Some applications of excited-state-excited-state transition densities

We derive an approximation for transition moments between excited states consistent with the approximations and assumptions normally used to obtain transition moments betwen the ground and excited states in the random-phase approximation and its higher-order approximations. We apply the result to the calculation of the photoionization cross sections of the 23S and 21S metastable states of helium by a numerical analytical continuation of the frequency-dependent polarizability. The procedure completely avoids the need for continuum basis functions. The cross sections agree well with the results of other calculations. We also predict an accurate two-photon decay rate for the 21S metastable state of helium. The entire procedure is immediately applicable to several problems involving photoionization of metastable states of molecules

A Case Study of the Impact of Bioenergy Development Upon Crop Production, Livestock Feeding, and Water Resource Usage in Kansas

The development of grain-based ethanol production in Kansas has had a marked impact upon the feedgrain and livestock industries of the state. The increased focus on feedgrain production stemming from ethanol development impacts the use and sustainability of Kansas water resources, and has changed the proportional mix of crops grown in the state. The need to handle increased amounts of feedgrains and to transport them to ethanol plants has affected the functional role of local grain elevators as well as the directional flow of grain within the state. The grain trucking industry has been dramatically affected by the increase in demand for moving both feedstock inputs and co-product outputs to and from ethanol plants in the state.Crop Production/Industries, Livestock Production/Industries, Resource /Energy Economics and Policy,

Vibratory Loads Data from a Wind-Tunnel Test of Structurally Tailored Model Helicopter Rotors

An experimental study was conducted in the Langley Transonic Dynamics Tunnel to investigate the use of a Bell Helicopter Textron (BHT) rotor structural tailoring concept, known as rotor nodalization, in conjunction with advanced blade aerodynamics as well as to evaluate rotor blade aerodynamic design methodologies. A 1/5-size, four-bladed bearingless hub, three sets of Mach-scaled model rotor blades were tested in forward flight from transition up to an advance ratio of 0.35. The data presented pertain only to the evaluation of the structural tailoring concept and consist of fixed-system and rotating system vibratory loads. These data will be useful for evaluating the effects of tailoring blade structural properties on fixed-system vibratory loads, as well as validating analyses used in the design of advanced rotor systems

\u3cem\u3ePhytophthora cinnamomi\u3c/em\u3e Colonized Reclaimed Surface Mined Sites in Eastern Kentucky: Implications for the Restoration of Susceptible Species

Appalachian forests are threatened by a number of factors, especially introduced pests and pathogens. Among these is Phytophthora cinnamomi, a soil-borne oomycete pathogen known to cause root rot in American chestnut, shortleaf pine, and other native tree species. This study was initiated to characterize the incidence of P. cinnamomi on surface mined lands in eastern Kentucky, USA, representing a range of time since reclamation (10, 12, 15, and 20 years since reclamation). Incidence of P. cinnamomi was correlated to soil properties including overall soil development, as indicated by a variety of measured soil physical and chemical parameters, especially the accumulation of soil organic carbon. P. cinnamomi was detected in only two of the four sites studied, aged 15 and 20 years since reclamation. These sites were generally characterized by higher organic matter accumulation than the younger sites in which P. cinnamomi was not detected. These results demonstrate that P. cinnamomi is capable of colonizing reclaimed mine sites in Appalachia; additional research is necessary to determine the impact of P. cinnamomi on susceptible tree species at these sites

GROUNDWATER RADIOIODINE: PREVALENCE, BIOGEOCHEMISTRY, AND POTENTIAL REMEDIAL APPROACHES

Iodine-129 ({sup 129}I) has not received as much attention in basic and applied research as other contaminants associated with DOE plumes. These other contaminants, such as uranium, plutonium, strontium, and technetium are more widespread and exist at more DOE facilities. Yet, at the Hanford Site and the Savannah River Site {sup 129}I occurs in groundwater at concentrations significantly above the primary drinking water standard and there is no accepted method for treating it, other than pump-and-treat systems. With the potential arrival of a 'Nuclear Renaissance', new nuclear power facilities will be creating additional {sup 129}I waste at a rate of 1 Ci/gigawatts energy produced. If all 22 proposed nuclear power facilities in the U.S. get approved, they will produce more {sup 129}I waste in seven years than presently exists at the two facilities containing the largest {sup 129}I inventories, ({approx}146 Ci {sup 129}I at the Hanford Site and the Savannah River Site). Hence, there is an important need to fully understand {sup 129}I behavior in the environment to clean up existing plumes and to support the expected future expansion of nuclear power production. {sup 129}I is among the key risk drivers at all DOE nuclear disposal facilities where {sup 129}I is buried, because of its long half-life (16 million years), high toxicity (90% of the body's iodine accumulates in the thyroid), high inventory, and perceived high mobility in the subsurface environment. Another important reason that {sup 129}I is a key risk driver is that there is the uncertainty regarding its biogeochemical fate and transport in the environment. We typically can define {sup 129}I mass balance and flux at sites, but can not accurately predict its response to changes in the environment. This uncertainty is in part responsible for the low drinking water standard, 1 pCi/L {sup 129}I, and the low permissible inventory limits (Ci) at the Savannah River Site, Hanford Site, and the former Yucca Mountain disposal facilities. The objectives of this report are to: (1) compile the background information necessary to understand behavior of {sup 129}I in the environment, (2) discuss sustainable remediation approaches to {sup 129}I contaminated groundwater, and (3) identify areas of research that will facilitate remediation of {sup 129}I contaminated areas on DOE sites. Lines of scientific inquiry that would significantly advance the goals of basic and applied research programs for accelerating {sup 129}I environmental remediation and reducing uncertainty associated with disposal of {sup 129}I waste are: (1) Evaluation of amendments or other treatment systems that can sequester subsurface groundwater {sup 129}I. (2) Develop analytical techniques for measurement of total {sup 129}I that eliminate the necessity of collecting and shipping large samples of groundwater. (3) Develop and evaluate ways to manipulate areas with organic-rich soil, such as wetlands, to maximize {sup 129}I sorption, minimizing releases during anoxic conditions. (4) Develop analytical techniques that can identify the various {sup 129}I species in the subsurface aqueous and solid phases at ambient concentrations and under ambient conditions. (5) Identify the mechanisms and factors controlling iodine-natural organic matter interactions at appropriate environmental concentrations. (6) Understand the biological processes that transform iodine species throughout different compartments of subsurface waste sites and the role that these processes have on {sup 129}I flux

How School Contexts Shape the Relations Among Adolescents' Beliefs, Peer Victimization, and Depressive Symptoms

The present research examined how school contexts shape the extent to which beliefs about the potential for change (implicit theories) interact with social adversity to predict depressive symptoms. A preregistered multilevel regression analysis using data from 6,237 ninth-grade adolescents in 25 U.S. high schools showed a three-way interaction: Implicit theories moderated the associations between victimization and depressive symptoms only in schools with high levels of school-level victimization, but not in schools with low victimization levels. In high-victimization schools, adolescents who believed that people cannot change (an entity theory of personality) were more depressed when they were victimized more frequently. Thus, the mental health correlates of adolescents' implicit theories depend on both personal experiences and the norms in the context

Development of Mine Soils in a Chronosequence of Forestry-Reclaimed Sites in Eastern Kentucky

Surface mining for coal has contributed to widespread deforestation and soil loss in coal mining regions around the world, and particularly in Appalachia, USA. Mined land reforestation is of interest in this and other regions where forests are the dominant pre-mining land use. This study evaluated mine soil development on surface-mined sites reforested according to the Forestry Reclamation Approach, representing a chronosequence of time ranging from 0 to 19 years after reclamation. Soils were sampled in depth increments to 50 cm and analyzed for a suite of soil physical and chemical characteristics. Overall, soil fines (silt + clay) tended to increase over time since reclamation (17% silt at year 0 increasing to 35% at year 11; 3.2% clay at year 0 increasing to 5.7% at year 14) while concentrations of metals (e.g., Al, Mg, Mn, Na) demonstrated varied relationships with time since reclamation. Concentrations of organic carbon (OC) tended to increase with time (0.9% OC at year 0 increasing to 2.3% at year 14), and were most enriched in near-surface soils. Some soil characteristics (e.g., Na, OC, Ca) demonstrated patterns of increasing similarity to the forest control, while others were distinct from the forest control throughout the chronosequence (e.g., Al, clay, Mn, gravel). Future surveys of these soils over time will elucidate longer-term patterns in soil development, and better characterize the time scales over which these soils might be expected to approximate forest soil conditions