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Controversies over Redefining “Fill Material” Under the Clean Water Act

Description: On May 3, 2002, the Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers (the Corps) announced a final rule redefining two key terms, “fill material” and “discharge of fill material,” in regulations that implement Section 404 of the Clean Water Act. This report discusses the revised rule, focusing on how it changes which material and types of activities are regulated under Section 404 and the significance of these issues, especially for the mining industry.
Date: August 21, 2008
Creator: Copeland, Claudia

Controversies over Redefining “Fill Material” Under the Clean Water Act

Description: This report discusses the Clean Water Act that contains two different permitting regimes: (1) Section 402 permits (called the National Pollutant Discharge Elimination System, or NPDES, permit program) address the discharge of most pollutants, and (2) Section 404 permits address the discharge of dredged or fill material into navigable waters of the United States at specified sites. These permit programs differ in nature and approach.
Date: April 20, 2009
Creator: Copeland, Claudia

Controversies over Redefining "Fill Material" Under the Clean Water Act

Description: On May 3, 2002, the Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers (the Corps) announced a regulation redefining two key terms, "fill material" and "discharge of fill material," in rules that implement Section 404 of the Clean Water Act. This report discusses the 2002 rule, focusing on how it changes which material and types of activities are regulated under Section 404 and the significance of these issues, especially for the mining industry.
Date: April 20, 2009
Creator: Copeland, Claudia

Convalency of Neptunium(IV) Organometallics from {sup 237}Np Moessbauer Spectra

Description: The results of {sup 237}Np Moessbauer spectra provide a picture of the bonding of {sup 237}Np organometallics and their uranium analogues that could be obtained by no other method. In essence, Moessbauer results give a view of the compound from the position of the neptunium nucleus; the work summarized in this paper shows that the {sup 237}Np isomer shift results are consistent with available data and provide a useful picture of the bonding in actinide organometallics.
Date: March 15, 2001
Creator: Karraker, D.G.

Convection Heat Transfer in Three-Dimensional Turbulent Separated/Reattached Flow

Description: The measurements and the simulation of convective heat transfer in separated flow have been a challenge to researchers for many years. Measurements have been limited to two-dimensional flow and simulations failed to predict accurately turbulent heat transfer in the separated and reattached flow region (prediction are higher than measurements by more than 50%). A coordinated experimental and numerical effort has been initiated under this grant for examining the momentum and thermal transport in three-dimensional separated and reattached flow in an effort to provide new measurements that can be used for benchmarking and for improving the simulation capabilities of 3-D convection in separated/reattached flow regime. High-resolution and non-invasive measurements techniques are developed and employed in this study to quantify the magnitude and the behavior of the three velocity components and the resulting convective heat transfer. In addition, simulation capabilities are developed and employed for improving the simulation of 3-D convective separated/reattached flow. Such basic measurements and simulation capabilities are needed for improving the design and performance evaluation of complex (3-D) heat exchanging equipment. Three-dimensional (3-D) convective air flow adjacent to backward-facing step in rectangular channel is selected for the experimental component of this study. This geometry is simple but it exhibits all the complexities that appear in any other separated/reattached flow, thus making the results generated in this study applicable to any other separated and reattached flow. Boundary conditions, inflow, outflow, and wall thermal treatment in this geometry can be well measured and controlled. The geometry can be constructed with optical access for non-intrusive measurements of the flow and thermal fields. A three-component laser Doppler velocimeter (LDV) is employed to measure simultaneously the three-velocity components and their turbulent fluctuations. Infrared thermography is utilized to measure the wall temperature and that information is used to determine the local convective heat transfer coefficient. ...
Date: October 31, 2007
Creator: Armaly, Bassem F.

Convection of a pattern of vorticity through a shock wave

Description: An arbitrary weak spatial distribution of vorticity can be represented in terms of plane sinusoidal shear waves of all orientations and wave lengths (Fourier integral). The analysis treats the passage of a single representative weak shear wave through a plane shock and shows refraction and modification of the shear wave with simultaneous generation of an acoustically intense sound wave. Applications to turbulence and to noise in supersonic wind tunnels are indicated.
Date: January 1, 1954
Creator: Ribner, H S

Convective effects in a regulatory and proposed fire model

Description: Radiation is the dominant mode of heat transfer in large fires. However, convection can be as much as 10 to 20 percent of the total heat transfer to an object in a large fire. The current radioactive material transportation packaging regulations include convection as a mode of heat transfer in the accident condition scenario. The current International Atomic Energy Agency Safety Series 6 packaging regulation states ``the convection coefficient shall be that value which the designer can justify if the package were exposed to the specified fire``. The current Title 10, Code of Federal Regulations, Part 71 (10CFR71) packaging regulation states ``when significant, convection heat input must be included on the basis of still, ambient air at 800{degrees}C (1475{degrees}F)``. Two questions that can arise in an analysts mind from an examination of the packaging regulations is whether convection is significant and whether convection should be included in the design analysis of a radioactive materials transportation container. The objective of this study is to examine the convective effects on an actual radioactive materials transportation package using a regulatory and a proposed thermal boundary condition.
Date: December 31, 1995
Creator: Wix, S.D. & Hohnstreiter, G.F.

Convective heat transfer and flow stability in rotating disk CVD reactors

Description: The flow and heat transfer of NH{sub 3} and He have been studied in a rotating disk system with applications to chemical vapor deposition reactors. Influence of the important operating parameters were studied numerically over ranges of the primary dimensionless variables: (1) the spin Reynolds number, Re{sub {omega}}, (2) the disk mixed convection parameter, MCP{sub d}, and (3) a new parameter, the wall mixed convection parameter, MCP{sub w}. Inlet velocities were set to the corresponding infinite rotating disk asymptotic velocity. Results were obtained primarily for NH{sub 3}. Results show that increasing Re{sub {omega}} from 314.5 to 3,145 increases the uniformity of the rotating disk heat flux and results in thinner thermal boundary layers at the disk surface. At Re{sub {omega}} = 314.5, increasing MCP{sub d} to 15 leads to significant departure from the infinite disk result with nonuniform disk heat fluxes and recirculating flow patterns. At Re{sub {omega}} = 3,145, the results are closer to the infinite disk for MCP{sub d} up to 15. For large values of MCP{sub w}, the flow recirculates and there is significant deviation from the infinite disk result. The influence of MCP{sub w} on flow stability is increased at larger MCP{sub d} and lower Re{sub {omega}}. The results show that because of variable transport properties, the flow of NH{sub 3} is less stable than that of He as MCP{sub d} is increased for MCP{sub w} = 0 and Re{sub {omega}} = 314.5.
Date: August 1998
Creator: Winters, W. S.; Evans, G. H. & Greif, R.

Convective heat transfer behavior of the product slurry of the nitrate to ammonia and ceramic (NAC) process

Description: The Nitrate to Ammonia and Ceramic (NAC) process is an innovative technology for immobilizing liquid form low level radioactive waste (LLW). An experimental study has been conducted to measure the heat transfer properties of the NAC product slurry. The results indicate that the heat transfer coefficient for both concentration slurries is much higher than that of pure water, which may be due to the higher conductivity of the gibbsite powder. For the 20% concentration slurry, the heat transfer coefficient increased as the generalized Reynolds number and slurry temperature increased. The heat transfer coefficient of 40% is a function of the Reynolds number only. The test results also indicate that the thermal entrance region can be observed only when the generalized Reynolds number is smaller than 1,000. The correlation equation is also developed based on the experimental data in this paper.
Date: December 1, 1995
Creator: Muguercia, I.; Yang, G.; Ebadian, M.A.; Lee, D.D.; Mattus, A.J. & Hunt, R.D.

Convective Heating of the LIFE Engine Target During Injection

Description: Target survival in the hostile, high temperature xenon environment of the proposed Laser Inertial Fusion Energy (LIFE) engine is critical. This work focuses on the flow properties and convective heat load imposed upon the surface of the indirect drive target while traveling through the xenon gas. While this rarefied flow is traditionally characterized as being within the continuum regime, it is approaching transition where conventional CFD codes reach their bounds of operation. Thus ANSYS, specifically the Navier-Stokes module CFX, will be used in parallel with direct simulation Monte Carlo code DS2V and analytically and empirically derived expressions for heat transfer to the hohlraum for validation. Comparison of the viscous and thermal boundary layers of ANSYS and DS2V were shown to be nearly identical, with the surface heat flux varying less than 8% on average. From the results herein, external baffles have been shown to reduce this heat transfer to the sensitive laser entrance hole (LEH) windows and optimize target survival independent of other reactor parameters.
Date: October 24, 2011
Creator: Holdener, D S; Tillack, M S & Wang, X R

Convenience Gambling: Information on Economic and Social Effects in Selected Locations

Description: A letter report issued by the General Accounting Office with an abstract that begins "This report summarizes GAO's findings on the economic and social effects of "convenience gambling." The National Gambling Impact Study Commission defines convenience gambling as the placement of slot machines or video poker terminals in restaurants, bars, drugstores, and other businesses to attract local residents rather than tourists. Although data from the communities GAO studied indicated that legalized convenience gambling increased tax revenues and created jobs, local government officials said that its presence discouraged some businesses from coming into the community. Although government officials in these communities suggested that convenience gambling contributed to bankruptcy filings, GAO was unable to find evidence of such a link. Many factors prevented GAO from clearly identifying the social effects of gambling in the communities studied. GAO was able to gather anecdotal evidence that suggested a link between certain social problems and gambling, but hard evidence to support those findings was lacking."
Date: October 18, 2000
Creator: United States. General Accounting Office.

Convenient synthesis of bis(benzo)-fused BEDT-TTF and higher homologues: new electron donor molecules for organic charge transfer salts and `molecular rulers`

Description: A convenient synthesis of bis(benzo)- and bis(naphtho)-fused bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF or ET) derivatives, employing the [4+2] cycloaddition reaction of oligo(1,3-dithiole-2,4, 5-trithione) with appropriate alkenes as a key step, is presented.
Date: October 1, 1996
Creator: Parakka, J.P.; Kini, A.M. & Williams, J.M.