Survey of synfuel technology for lignite

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sondreal, E.A.

1982-01-01

The most important market for lignite will continue to be the electric utility industry, where it is used to fuel large pc-fired boilers serving major regional power grids. However, the growth of this market and thechnology is being challenged by new and more stringent environmental control requirements, including the international concern over acid rain. Environmental and economic issues could either encourage or limit the development of a synfuels market for lignite depending on the cost effectiveness of the technological solutions that are developed. Clearly the United States needs to develop its coal resources to reduce dependence on imported oil. However,more » demand for coal derived substitute petroleum will be constrained by cost for the forseeable future. Government policy initiatives and new technology will be the keys to removing these constraints in the decades ahead. A crossover point with respect to petroleum and natural gas will be reached at some point in the future, which will allow synthetic fuels to penetrate the markets now served by oil and gas. Those of us who are today concerned with the development of lignite resources can look forward to participating in the major synfuels market that will emerge when those economic conditions are realized.« less

Outlook for alternative energy sources. [aviation fuels

NASA Technical Reports Server (NTRS)

Card, M. E.

1980-01-01

Predictions are made concerning the development of alternative energy sources in the light of the present national energy situation. Particular emphasis is given to the impact of alternative fuels development on aviation fuels. The future outlook for aircraft fuels is that for the near term, there possibly will be no major fuel changes, but minor specification changes may be possible if supplies decrease. In the midterm, a broad cut fuel may be used if current development efforts are successful. As synfuel production levels increase beyond the 1990's there may be some mixtures of petroleum-based and synfuel products with the possibility of some shale distillate and indirect coal liquefaction products near the year 2000.

Production of Liquid Synthetic Fuels from Carbon, Water and Nuclear Power on Ships and at Shore Bases for Military and Potential Commercial Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Locke Bogart, S.; Schultz, Ken; Brown, Lloyd

2006-07-01

It is demonstrable that synthetic fuels (jet/diesel/gasoline {approx_equal} (CH{sub 2}){sub n}) can be produced from carbon, water, and nuclear energy. What remains to be shown is that all system processes are scalable, integrable, and economical. Sources of carbon include but are not limited to CO{sub 2} from the atmosphere or seawater, CO{sub 2} from fossil-fired power plants, and elemental carbon from coal or biomass. For mobile defense (Navy) applications, the ubiquitous atmosphere is our chosen carbon source. For larger-scale sites such as Naval Advance Bases, the atmosphere may still be the choice should other sources not be readily available. However, at many locations suitable for defense and, potentially, commercial syn-fuel production, far higher concentrations of carbon may be available. The rationale for this study was manifold: fuel system security from terrorism and possible oil embargoes; rising demand and, eventually, peaking supply of conventional petroleum; and escalating costs and prices of fuels. For these reasons, the initial parts of the study were directed at Syn-fuel production for mobile Naval platforms and shore sites such as Rokkasho, Japan (as an exemplar). Nuclear reactors would provide the energy for H{sub 2} from water-splitting, Membrane Gas Absorption (MGA) would extract CO{sub 2} from the atmosphere, the Reverse Water-Gas Reaction (RWGR) would convert the CO{sub 2} to CO, and the resultant H{sub 2} and CO feeds would be converted to (CH{sub 2})n by the Fischer-Tropsch reaction. Many of these processes exist at commercial scale. Some, particularly MGA and RWGR, have been demonstrated at the bench-scale, requiring up-scaling. Likewise, the demonstration of an integrated system at some scale is yet to be done. For ship-based production, it has been shown that the system should be viable and, under reasonable assumptions, both scalable and economical for defense fuels. For the assumptions in the study, fuel cost estimates range from {approx}more » $2.55 to $$4.75 per gallon with a nominal cost of {approx} $$3.65 per gallon. For large installations and advanced nuclear power and hydrogen production systems (high temperature reactors and thermo-chemical hydrogen production), then fuel production might be produced at near-commercial fuel prices. For the H2-MHR and plausible assumptions and estimates of CO{sub 2} extraction and fuel synthesis capital and operating costs, such fuels might have nominal and low production costs ranging from {approx} $2.40 to $$1.70 per gallon, respectively, for a Public Sector Fixed Charge Rate of 5%. Next, it was shown that for CO{sub 2} provided from a fossil-fired power plant, a CO{sub 2} 'disposal' fee of $$30/tonne and a Fixed Charge Rate of 10%, then syn-fuel might be produced at {approx} $3.00 and $2.45 (nominal cost values) and $1.90 and $$1.85 (low cost values) per gallon by LWRs and H2-MHRs, respectively. Last, it was shown that nuclear-produced H{sub 2} and O{sub 2} could convert coal to liquid fuels at very low cost. For a Fixed Charge Rate of 10% and nominal plant costs, fuel costs ranged from {approx} $$1.60 (LWR) per gallon to {approx} $$1.30 (H2-MHR) for an assumed CO{sub 2} avoidance credit of $$30/Tonne. Our studies have shown that the addition of nuclear-produced hydrogen and oxygen to the coal syn-fuel process can greatly reduce CO{sub 2} production and, for modest CO{sub 2} credit, can further reduce the cost of the syn-fuel. Capturing CO{sub 2} from stack gas or even the air will further reduce the amount of CO{sub 2} that must be dealt with. This last case is independent of the price of fossil fuels and liquid fuel production costs and prices will have been capped. Of possibly even greater importance, the carbon fuel cycle will have been closed, thus minimizing or eliminating concerns with Global Climate Change. (authors)« less

Low NO/x/ heavy fuel combustor program

NASA Technical Reports Server (NTRS)

Lister, E.; Niedzwiecki, R. W.; Nichols, L.

1980-01-01

The paper deals with the 'Low NO/x/ Heavy Fuel Combustor Program'. Main program objectives are to generate and demonstrate the technology required to develop durable gas turbine combustors for utility and industrial applications, which are capable of sustained, environmentally acceptable operation with minimally processed petroleum residual fuels. The program will focus on 'dry' reductions of oxides of nitrogen (NO/x/), improved combustor durability and satisfactory combustion of minimally processed petroleum residual fuels. Other technology advancements sought include: fuel flexibility for operation with petroleum distillates, blends of petroleum distillates and residual fuels, and synfuels (fuel oils derived from coal or shale); acceptable exhaust emissions of carbon monoxide, unburned hydrocarbons, sulfur oxides and smoke; and retrofit capability to existing engines.

Low NO(x) heavy fuel combustor program

NASA Technical Reports Server (NTRS)

Lister, E.; Niedzwiecki, R. W.; Nichols, L.

1979-01-01

The 'low nitrogen oxides heavy fuel combustor' program is described. Main program objectives are to generate and demonstrate the technology required to develop durable gas turbine combustors for utility and industrial applications, which are capable of sustained, environmentally acceptable operation with minimally processed petroleum residual fuels. The program will focus on 'dry' reductions of oxides of nitrogen, improved combustor durability, and satisfactory combustion of minimally processed petroleum residual fuels. Other technology advancements sought include: fuel flexibility for operation with petroleum distillates, blends of petroleum distillates and residual fuels, and synfuels (fuel oils derived from coal or shale); acceptable exhaust emissions of carbon monoxide, unburned hydrocarbons, sulfur oxides and smoke; and retrofit capability to existing engines.

Pacific Northwest Laboratory annual report for 1983 to the DOE Office of Energy Research. Part 1. Biomedical sciences

DOE Office of Scientific and Technical Information (OSTI.GOV)

Drucker, H.

1983-02-01

Biomedical and health effects research conducted at PNL in 1982 on the evaluation of risk to man from existing and/or developing energy-related technologies are described. Most of the studies described in this report relate to activities for three major energy technologies: nuclear fuel cycle; fossil fuel cycle (oil, gas, and coal process technologies, mining, and utilization; synfuel development), and fudion (biomagnetic effects). The report is organized under these technologies. In addition, research reports are included on the application of nuclear energy to biomedical problems. Individual projects are indexed separately.

Water Availability for Synthetic Fuels: An Assessment of Current Studies

DOT National Transportation Integrated Search

1982-10-01

The objective of this study is to describe and analyze the hydrologic, institutional, legal, and economic issues involved in assessing and interpreting estimates of water availability for synfuels development in four major river basins: (1) Upper Mis...

California methanol assessment. Volume 2: Technical report

NASA Technical Reports Server (NTRS)

Otoole, R.; Dutzi, E.; Gershman, R.; Heft, R.; Kalema, W.; Maynard, D.

1983-01-01

Energy feedstock sources for methanol; methanol and other synfuels; transport, storage, and distribution; air quality impact of methanol use in vehicles, chemical methanol production and use; methanol utilization in vehicles; methanol utilization in stationary applications; and environmental and regulatory constraints are discussed.

General Lectures: Looking Ahead, Looking Around, Looking Back.

ERIC Educational Resources Information Center

Journal of Chemical Education, 1983

1983-01-01

Highlights general papers presented at the Seventh Biennial Conference on Chemical Education (Stillwater, Oklahoma 1982). Topics focused on suggested changes to improve chemistry instruction/curriculum, chemistry of synfuels, science/manufacturing in low-earth orbit, status of chemical education, chemical education history, and history of…

Status and future opportunities for conversion of synthesis gas to liquid energy fuels: Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mills, G.

The manufacture of liquid energy fuels from syngas (a mixture of H[sub 2] and CO, usually containing CO[sub 2]) is of growing importance and enormous potential because: (1) Abundant US supplies of coal, gas, and biomass can be used to provide the needed syngas. (2) The liquid fuels produced, oxygenates or hydrocarbons, can help lessen environmental pollution. Indeed, oxygenates are required to a significant extent by the Clean Air Act Amendments (CAAA) of 1990. (3) Such liquid synfuels make possible high engine efficiencies because they have high octane or cetane ratings. (4) There is new, significantly improved technology for convertingmore » syngas to liquid fuels and promising opportunities for further improvements. This is the subject of this report. The purpose of this report is to provide an account and evaluative assessment of advances in the technology for producing liquid energy fuels from syngas and to suggest opportunities for future research deemed promising for practical processes. Much of the improved technology for selective synthesis of desired fuels from syngas has resulted from advances in catalytic chemistry. However, novel process engineering has been particularly important recently, utilizing known catalysts in new configurations to create new catalytic processes. This report is an update of the 1988 study Catalysts for Fuels from Syngas: New Directions for Research (Mills 1988), which is included as Appendix A. Technology for manufacture of syngas is not part of this study. The manufacture of liquid synfuels is capital intensive. Thus, in evaluating advances in fuels technology, focus is on the potential for improved economics, particularly on lowering plant investment costs. A second important criteria is the potential for environmental benefits. The discussion is concerned with two types of hydrocarbon fuels and three types of oxygenate fuels that can be synthesized from syngas. Seven alternative reaction pathways are involved.« less

Status and future opportunities for conversion of synthesis gas to liquid energy fuels: Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mills, G

The manufacture of liquid energy fuels from syngas (a mixture of H{sub 2} and CO, usually containing CO{sub 2}) is of growing importance and enormous potential because: (1) Abundant US supplies of coal, gas, and biomass can be used to provide the needed syngas. (2) The liquid fuels produced, oxygenates or hydrocarbons, can help lessen environmental pollution. Indeed, oxygenates are required to a significant extent by the Clean Air Act Amendments (CAAA) of 1990. (3) Such liquid synfuels make possible high engine efficiencies because they have high octane or cetane ratings. (4) There is new, significantly improved technology for convertingmore » syngas to liquid fuels and promising opportunities for further improvements. This is the subject of this report. The purpose of this report is to provide an account and evaluative assessment of advances in the technology for producing liquid energy fuels from syngas and to suggest opportunities for future research deemed promising for practical processes. Much of the improved technology for selective synthesis of desired fuels from syngas has resulted from advances in catalytic chemistry. However, novel process engineering has been particularly important recently, utilizing known catalysts in new configurations to create new catalytic processes. This report is an update of the 1988 study Catalysts for Fuels from Syngas: New Directions for Research (Mills 1988), which is included as Appendix A. Technology for manufacture of syngas is not part of this study. The manufacture of liquid synfuels is capital intensive. Thus, in evaluating advances in fuels technology, focus is on the potential for improved economics, particularly on lowering plant investment costs. A second important criteria is the potential for environmental benefits. The discussion is concerned with two types of hydrocarbon fuels and three types of oxygenate fuels that can be synthesized from syngas. Seven alternative reaction pathways are involved.« less

78 FR 53135 - Agency Information Collection Extension

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-28

... Synfuel data Minor revisions to instructions and definitions Form EIA-7A: Coal Production and Preparation... Production and Preparation Report;'' EIA-8A ``Coal Stocks Report;'' EIA-20 ``Weekly Coal Monitoring Report... environment. EIA surveys are conducted to collect coal market data. The data elements include production...

Synthetic fuels development: earth-science considerations

USGS Publications Warehouse

Rickert, D. A.; Ulman, W.J.; Hampton, E.R.

1979-01-01

The current energy crisis is affecting the lives of all Americans. Continued increases in energy prices and frequent shortages are stark reminders of our growing dependence on foreign energy resources in today's energy-hungry world. A comprehensive national energy policy must consider a variety of energy resources, including synfuels, to meet future energy needs.

Synthetic fuels development in Kentucky: Four scenarios for an energy future as constructed from lessons of the past

NASA Astrophysics Data System (ADS)

Musulin, Mike, II

The continued failure of synthetic fuels development in the United States to achieve commercialization has been documented through the sporadic periods of mounting corporate and government enthusiasm and high levels of research and development efforts. Four periods of enthusiasm at the national level were followed by waning intervals of shrinking financial support and sagging R&D work. The continuing cycle of mobilization and stagnation has had a corresponding history in Kentucky. To better understand the potential and the pitfalls of this type of technological development the history of synthetic fuels development in the United States is presented as background, with a more detailed analysis of synfuels development in Kentucky. The first two periods of interest in synthetic fuels immediately after the Second World War and in the 1950s did not result in any proposed plants for Kentucky, but the third and fourth periods of interest created a great deal of activity. A theoretically grounded case study is utilized in this research project to create four different scenarios for the future of synthetic fuels development. The Kentucky experience is utilized in this case study because a fifth incarnation of synthetic fuels development has been proposed for the state in the form of an integrated gasification combined cycle power plant (IGCC) to utilize coal and refuse derived fuel (RDF). The project has been awarded a grant from the U.S. Department of Energy Clean Coal Technology program. From an examination and analysis of these periods of interest and the subsequent dwindling of interest and participation, four alternative scenarios are constructed. A synfuels breakthrough scenario is described whereby IGCC becomes a viable part of the country's energy future. A multiplex scenario describes how IGCC becomes a particular niche in energy production. The status quo scenario describes how the old patterns of project failure repeat themselves. The fourth scenario describes how synfuels and other conventional energy sources are rejected in favor of conservation, use of nuclear facilities, and use of alternative fuels.

Ionic Mechanisms of Carbon Formation in Flames.

DTIC Science & Technology

1981-05-01

EFFECT OF MOLECULAR STRUCTURE ON INCIPIENT SOOT FORMATION, H.F. Calcote and D.M. Manos APPENDIX E: CORRELATION OF SOOT FORMATION IN TURBOJET ENGINES...future use by the Air Force of synfuels derived from coal, tar sands, and shale oil . These fuels are expected to have higher molecular weights, more...emissions and flame radiation from turbojet engines and larger scale combustors simulating practical engine conditions. b. Interpret and correlate the

Feasibility study report for the Imperial Valley Ethanol Refinery: a 14. 9-million-gallon-per-year ethanol synfuel refinery utilizing geothermal energy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1981-03-01

The construction and operation of a 14,980,000 gallon per year fuel ethanol from grain refinery in the Imperial Valley of California is proposed. The Imperial Valley Ethanol Refinery (refinery) will use hot geothermal fluid from geothermal resources at the East Mesa area as the source of process energy. In order to evaluate the economic viability of the proposed Project, exhaustive engineering, cost analysis, and financial studies have been undertaken. This report presents the results of feasibility studies undertaken in geothermal resource, engineering, marketing financing, management, environment, and permits and approvals. The conclusion of these studies is that the Project ismore » economically viable. US Alcohol Fuels is proceeding with its plans to construct and operate the Refinery.« less

Liquid fuel supplies

NASA Astrophysics Data System (ADS)

Perry, H.

1980-06-01

This paper presents an overview of United States and world petroleum, natural gas, and natural gas liquids presumed recoverable but as yet undiscovered resources and suggests that the depletion of these fuels may not occur as quickly as frequently predicted. The paper points out that the construction of a synthetic fuels industry will be very costly and will provide only a small amount of increased energy independence. The fear is expressed that haste in accepting a specific synfuels process on the basis of present technology may serve to forestall the development of a better technology. The paper suggests that we construct relatively few plants now each using a different technology in order to gain better understanding of the various technologies, more information on costs and the essential but as yet unknown information on environmental and socioeconomic effects of large scale plants.

U.S. Lake Erie Natural Gas Resource Development. Final Programmatic Environmental Impact Statement

DTIC Science & Technology

1982-03-01

with expensive investments by end-users in more energy efficient houses, plants and equipment. The end result of this alternative would be to post...construction of transmission systems from other sources into the Lake Erie watershed, construction of synfuel and coal gasi- fication plants and...water treatment plant and by main- taining the pit near neutral during chlorination. 1.022 If jack-up rigs, drillehips, or stimulation barges capsize

Resource and energy management of synfuels production with hydrogen and oxygen requirements from electrolysis

NASA Astrophysics Data System (ADS)

Shannon, R. H.; Richardson, R. D.

The Resource and Energy Management System (REM), which uses electrolytic H2 and O2 to produce synthetic crude and light oils from heavy hydrocarbons is described. The heavy hydrocarbon feedstocks include heavy oils, tar sand bitumens, heavy residual oils, oil shale kerogens, liquefied coal, and pyrolytically-extracted coal liquids. The system includes mini-upgraders, which can be implemented in modular form, to pump electrolytically-derived H2 into heavy oils to upgrade their energy content. Projected costs for the production of synthetic light oils using U.S. coal reserves with the REM process after liquefaction are $30-35/bbl, with the H2 costs being a controlling factor. The modular systems could be built in a much shorter time frame than much larger projects, and would be instrumental in establishing the electrolytic H2 production infrastructure needed for eventual full conversion to an H2-based economy.

Synfuel program analysis. Volume 2: VENVAL users manual

NASA Astrophysics Data System (ADS)

Muddiman, J. B.; Whelan, J. W.

1980-07-01

This volume is intended for program analysts and is a users manual for the VENVAL model. It contains specific explanations as to input data requirements and programming procedures for the use of this model. VENVAL is a generalized computer program to aid in evaluation of prospective private sector production ventures. The program can project interrelated values of installed capacity, production, sales revenue, operating costs, depreciation, investment, dent, earnings, taxes, return on investment, depletion, and cash flow measures. It can also compute related public sector and other external costs and revenues if unit costs are furnished.

Georgia Power's Coal-Derived Synfuel Proposal

EPA Pesticide Factsheets

This document may be of assistance in applying the Title V air operating permit regulations. This document is part of the Title V Policy and Guidance Database available at www2.epa.gov/title-v-operating-permits/title-v-operating-permit-policy-and-guidance-document-index. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

Process wastewater treatability study for Westinghouse fluidized-bed coal gasification

DOE Office of Scientific and Technical Information (OSTI.GOV)

Winton, S.L.; Buvinger, B.J.; Evans, J.M.

1983-11-01

In the development of a synthetic fuels facility, water usage and wastewater treatment are major areas of concern. Coal gasification processes generally produce relatively large volumes of gas condensates. These wastewaters are typically composed of a variety of suspended and dissolved organic and inorganic solids and dissolved gaseous contaminants. Fluidized-bed coal gasification (FBG) processes are no exception to this rule. The Department of Energy's Morgantown Energy Technology Center (METC), the Gas Research Institute (GRI), and the Environmental Protection Agency (EPA/IERLRTP) recognized the need for a FBG treatment program to provide process design data for FBG wastewaters during the environmental, health,more » and safety characterization of the Westinghouse Process Development Unit (PDU). In response to this need, METC developed conceptual designs and a program plan to obtain process design and performance data for treating wastewater from commercial-scale Westinghouse-based synfuels plants. As a result of this plan, METC, GRI, and EPA entered into a joint program to develop performance data, design parameters, conceptual designs, and cost estimates for treating wastewaters from a FBG plant. Wastewater from the Westinghouse PDU consists of process quench and gas cooling condensates which are similar to those produced by other FBG processes such as U-Gas, and entrained-bed gasification processes such as Texaco. Therefore, wastewater from this facility was selected as the basis for this study. This paper outlines the current program for developing process design and cost data for the treatment of these wastewaters.« less

Discretized Streams: A Fault-Tolerant Model for Scalable Stream Processing

DTIC Science & Technology

2012-12-14

Discretized Streams: A Fault-Tolerant Model for Scalable Stream Processing Matei Zaharia Tathagata Das Haoyuan Li Timothy Hunter Scott Shenker Ion...SUBTITLE Discretized Streams: A Fault-Tolerant Model for Scalable Stream Processing 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER...time. However, current programming models for distributed stream processing are relatively low-level often leaving the user to worry about consistency of

Energy Remote Sensing Applications Projects at the NASA Ames Research Center

NASA Technical Reports Server (NTRS)

Norman, S. D.; Likens, W. C.; Mouat, D. A.

1982-01-01

The NASA Ames Research Center is active in energy projects primarily in the role of providing assistance to users in the solution of a number of problems related to energy. Data bases were produced which can be used, in combination with other sources of information, to solve spatially related energy problems. Six project activities at Ames are described which relate to energy and remote sensing. Two projects involve power demand forecasting and estimations using remote sensing and geographic information systems; two others involve transmission line routing and corridor analysis; one involves a synfuel user needs assessment through remote sensing; and the sixth involves the siting of energy facilities.

Method for enhanced atomization of liquids

DOEpatents

Thompson, Richard E.; White, Jerome R.

1993-01-01

In a process for atomizing a slurry or liquid process stream in which a slurry or liquid is passed through a nozzle to provide a primary atomized process stream, an improvement which comprises subjecting the liquid or slurry process stream to microwave energy as the liquid or slurry process stream exits the nozzle, wherein sufficient microwave heating is provided to flash vaporize the primary atomized process stream.

Fuel quality processing study, volume 1

NASA Astrophysics Data System (ADS)

Ohara, J. B.; Bela, A.; Jentz, N. E.; Syverson, H. T.; Klumpe, H. W.; Kessler, R. E.; Kotzot, H. T.; Loran, B. L.

1981-04-01

A fuel quality processing study to provide a data base for an intelligent tradeoff between advanced turbine technology and liquid fuel quality, and also, to guide the development of specifications of future synthetic fuels anticipated for use in the time period 1985 to 2000 is given. Four technical performance tests are discussed: on-site pretreating, existing refineries to upgrade fuels, new refineries to upgrade fuels, and data evaluation. The base case refinery is a modern Midwest refinery processing 200,000 BPD of a 60/40 domestic/import petroleum crude mix. The synthetic crudes used for upgrading to marketable products and turbine fuel are shale oil and coal liquids. Of these syncrudes, 50,000 BPD are processed in the existing petroleum refinery, requiring additional process units and reducing petroleum feed, and in a new refinery designed for processing each syncrude to produce gasoline, distillate fuels, resid fuels, and turbine fuel, JPGs and coke. An extensive collection of synfuel properties and upgrading data was prepared for the application of a linear program model to investigate the most economical production slate meeting petroleum product specifications and turbine fuels of various quality grades. Technical and economic projections were developed for 36 scenarios, based on 4 different crude feeds to either modified existing or new refineries operated in 2 different modes to produce 7 differing grades of turbine fuels. A required product selling price of turbine fuel for each processing route was calculated. Procedures and projected economics were developed for on-site treatment of turbine fuel to meet limitations of impurities and emission of pollutants.

Fuel quality processing study, volume 1

NASA Technical Reports Server (NTRS)

Ohara, J. B.; Bela, A.; Jentz, N. E.; Syverson, H. T.; Klumpe, H. W.; Kessler, R. E.; Kotzot, H. T.; Loran, B. L.

1981-01-01

A fuel quality processing study to provide a data base for an intelligent tradeoff between advanced turbine technology and liquid fuel quality, and also, to guide the development of specifications of future synthetic fuels anticipated for use in the time period 1985 to 2000 is given. Four technical performance tests are discussed: on-site pretreating, existing refineries to upgrade fuels, new refineries to upgrade fuels, and data evaluation. The base case refinery is a modern Midwest refinery processing 200,000 BPD of a 60/40 domestic/import petroleum crude mix. The synthetic crudes used for upgrading to marketable products and turbine fuel are shale oil and coal liquids. Of these syncrudes, 50,000 BPD are processed in the existing petroleum refinery, requiring additional process units and reducing petroleum feed, and in a new refinery designed for processing each syncrude to produce gasoline, distillate fuels, resid fuels, and turbine fuel, JPGs and coke. An extensive collection of synfuel properties and upgrading data was prepared for the application of a linear program model to investigate the most economical production slate meeting petroleum product specifications and turbine fuels of various quality grades. Technical and economic projections were developed for 36 scenarios, based on 4 different crude feeds to either modified existing or new refineries operated in 2 different modes to produce 7 differing grades of turbine fuels. A required product selling price of turbine fuel for each processing route was calculated. Procedures and projected economics were developed for on-site treatment of turbine fuel to meet limitations of impurities and emission of pollutants.

Evaluations in support of regulatory and research decisions by the U. S. Environmental Protection Agency for the control of toxic hazards from hazardous wastes, glyphosate, dalapon, and synthetic fuels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scofield, R.

1984-01-01

This report includes toxicological and regulatory evaluations performed in support of U.S. EPA regulation of toxic materials and hazardous wastes. The first section of the report describes evaluations which support: (a) the regulation of small-volume generators of hazardous wastes, (b) the regulation of hazardous wastes from pesticide manufacturing, and (c) the disposal of the herbicide, silvex. The second section describes the environmental fate, transport, and effect of glyphosate and dalapon. The third section deals with synthetic fuels, including evaluations of synfuel-product toxicity, uncontrolled air emissions, and particular focus on the toxicity of products from several indirect coal liquefaction processes includingmore » methanol synthesis, Fischer-Tropsch, Mobil M-Gasoline, and Lurgi gasification technologies. Three direct coal liquefaction processes were examined for product toxicity and air emissions: Solvent Refined Coal (I and II) and the Exxon Donor Solvent Process. Also described in the third section is an evaluation of environmental and health hazards associated with the use of synthetic fuels from indirect coal liquefaction, direct coal liquefaction, and shale oil. Finally, the fourth section discusses some problems associated with performing, on a contractual basis, scientific and technical evaluations in support of U.S. EPA regulatory and research decisions.« less

Apparatus for the liquefaction of natural gas and methods relating to same

DOEpatents

Wilding, Bruce M [Idaho Falls, ID; McKellar, Michael G [Idaho Falls, ID; Turner, Terry D [Ammon, ID; Carney, Francis H [Idaho Falls, ID

2009-09-29

An apparatus and method for producing liquefied natural gas. A liquefaction plant may be coupled to a source of unpurified natural gas, such as a natural gas pipeline at a pressure letdown station. A portion of the gas is drawn off and split into a process stream and a cooling stream. The cooling stream passes through an expander creating work output. A compressor may be driven by the work output and compresses the process stream. The compressed process stream is cooled, such as by the expanded cooling stream. The cooled, compressed process stream is divided into first and second portions with the first portion being expanded to liquefy the natural gas. A gas-liquid separator separates the vapor from the liquid natural gas. The second portion of the cooled, compressed process stream is also expanded and used to cool the compressed process stream.

Methods of natural gas liquefaction and natural gas liquefaction plants utilizing multiple and varying gas streams

DOEpatents

Wilding, Bruce M; Turner, Terry D

2014-12-02

A method of natural gas liquefaction may include cooling a gaseous NG process stream to form a liquid NG process stream. The method may further include directing the first tail gas stream out of a plant at a first pressure and directing a second tail gas stream out of the plant at a second pressure. An additional method of natural gas liquefaction may include separating CO.sub.2 from a liquid NG process stream and processing the CO.sub.2 to provide a CO.sub.2 product stream. Another method of natural gas liquefaction may include combining a marginal gaseous NG process stream with a secondary substantially pure NG stream to provide an improved gaseous NG process stream. Additionally, a NG liquefaction plant may include a first tail gas outlet, and at least a second tail gas outlet, the at least a second tail gas outlet separate from the first tail gas outlet.

Apparatus for the liquefaction of natural gas and methods relating to same

DOEpatents

Wilding, Bruce M [Idaho Falls, ID; Bingham, Dennis N [Idaho Falls, ID; McKellar, Michael G [Idaho Falls, ID; Turner, Terry D [Ammon, ID; Raterman, Kevin T [Idaho Falls, ID; Palmer, Gary L [Shelley, ID; Klingler, Kerry M [Idaho Falls, ID; Vranicar, John J [Concord, CA

2007-05-22

An apparatus and method for producing liquefied natural gas. A liquefaction plant may be coupled to a source of unpurified natural gas, such as a natural gas pipeline at a pressure letdown station. A portion of the gas is drawn off and split into a process stream and a cooling stream. The cooling stream passes through a turbo expander creating work output. A compressor is driven by the work output and compresses the process stream. The compressed process stream is cooled, such as by the expanded cooling stream. The cooled, compressed process stream is divided into first and second portions with the first portion being expanded to liquefy the natural gas. A gas-liquid separator separates the vapor from the liquid natural gas. The second portion of the cooled, compressed process stream is also expanded and used to cool the compressed process stream. Additional features and techniques may be integrated with the liquefaction process including a water clean-up cycle and a carbon dioxide (CO.sub.2) clean-up cycle.

Apparatus For The Liquefaaction Of Natural Gas And Methods Relating To Same

DOEpatents

Wilding, Bruce M.; Bingham, Dennis N.; McKellar, Michael G.; Turner, Terry D.; Rateman, Kevin T.; Palmer, Gary L.; Klinger, Kerry M.; Vranicar, John J.

2005-11-08

An apparatus and method for producing liquefied natural gas. A liquefaction plant may be coupled to a source of unpurified natural gas, such as a natural gas pipeline at a pressure letdown station. A portion of the gas is drawn off and split into a process stream and a cooling stream. The cooling stream passes through a turbo expander creating work output. A compressor is driven by the work output and compresses the process stream. The compressed process stream is cooled, such as by the expanded cooling stream. The cooled, compressed process stream is divided into first and second portions with the first portion being expanded to liquefy the natural gas. A gas-liquid separator separates the vapor from the liquid natural gas. The second portion of the cooled, compressed process stream is also expanded and used to cool the compressed process stream. Additional features and techniques may be integrated with the liquefaction process including a water clean-up cycle and a carbon dioxide (CO2) clean-up cycle.

Apparatus For The Liquefaaction Of Natural Gas And Methods Relating To Same

DOEpatents

Wilding, Bruce M.; Bingham, Dennis N.; McKellar, Michael G.; Turner, Terry D.; Raterman, Kevin T.; Palmer, Gary L.; Klingler, Kerry M.; Vranicar, John J.

2005-05-03

An apparatus and method for producing liquefied natural gas. A liquefaction plant may be coupled to a source of unpurified natural gas, such as a natural gas pipeline at a pressure letdown station. A portion of the gas is drawn off and split into a process stream and a cooling stream. The cooling stream passes through a turbo expander creating work output. A compressor is driven by the work output and compresses the process stream. The compressed process stream is cooled, such as by the expanded cooling stream. The cooled, compressed process stream is divided into first and second portions with the first portion being expanded to liquefy the natural gas. A gas-liquid separator separates the vapor from the liquid natural gas. The second portion of the cooled, compressed process stream is also expanded and used to cool the compressed process stream. Additional features and techniques may be integrated with the liquefaction process including a water clean-up cycle and a carbon dioxide (CO2) clean-up cycle.

Apparatus For The Liquefaaction Of Natural Gas And Methods Relating To Same

DOEpatents

Wilding, Bruce M.; Bingham, Dennis N.; McKellar, Michael G.; Turner, Terry D.; Raterman, Kevin T.; Palmer, Gary L.; Klingler, Kerry M.; Vranicar, John J.

2003-06-24

An apparatus and method for producing liquefied natural gas. A liquefaction plant may be coupled to a source of unpurified natural gas, such as a natural gas pipeline at a pressure letdown station. A portion of the gas is drawn off and split into a process stream and a cooling stream. The cooling stream passes through a turbo expander creating work output. A compressor is driven by the work output and compresses the process stream. The compressed process stream is cooled, such as by the expanded cooling stream. The cooled, compressed process stream is divided into first and second portions with the first portion being expanded to liquefy the natural gas. A gas-liquid separator separates the vapor from the liquid natural gas. The second portion of the cooled, compressed process stream is also expanded and used to cool the compressed process stream. Additional features and techniques may be integrated with the liquefaction process including a water clean-up cycle and a carbon dioxide (CO.sub.2) clean-up cycle.

Removal of hydrogen sulfide as ammonium sulfate from hydropyrolysis product vapors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marker, Terry L.; Felix, Larry G.; Linck, Martin B.

A system and method for processing biomass into hydrocarbon fuels that includes processing a biomass in a hydropyrolysis reactor resulting in hydrocarbon fuels and a process vapor stream and cooling the process vapor stream to a condensation temperature resulting in an aqueous stream. The aqueous stream is sent to a catalytic reactor where it is oxidized to obtain a product stream containing ammonia and ammonium sulfate. A resulting cooled product vapor stream includes non-condensable process vapors comprising H.sub.2, CH.sub.4, CO, CO.sub.2, ammonia and hydrogen sulfide.

Removal of hydrogen sulfide as ammonium sulfate from hydropyrolysis product vapors

DOEpatents

Marker, Terry L; Felix, Larry G; Linck, Martin B; Roberts, Michael J

2014-10-14

A system and method for processing biomass into hydrocarbon fuels that includes processing a biomass in a hydropyrolysis reactor resulting in hydrocarbon fuels and a process vapor stream and cooling the process vapor stream to a condensation temperature resulting in an aqueous stream. The aqueous stream is sent to a catalytic reactor where it is oxidized to obtain a product stream containing ammonia and ammonium sulfate. A resulting cooled product vapor stream includes non-condensable process vapors comprising H.sub.2, CH.sub.4, CO, CO.sub.2, ammonia and hydrogen sulfide.

Prioritized Contact Transport Stream

NASA Technical Reports Server (NTRS)

Hunt, Walter Lee, Jr. (Inventor)

2015-01-01

A detection process, contact recognition process, classification process, and identification process are applied to raw sensor data to produce an identified contact record set containing one or more identified contact records. A prioritization process is applied to the identified contact record set to assign a contact priority to each contact record in the identified contact record set. Data are removed from the contact records in the identified contact record set based on the contact priorities assigned to those contact records. A first contact stream is produced from the resulting contact records. The first contact stream is streamed in a contact transport stream. The contact transport stream may include and stream additional contact streams. The contact transport stream may be varied dynamically over time based on parameters such as available bandwidth, contact priority, presence/absence of contacts, system state, and configuration parameters.

Feature integration and object representations along the dorsal stream visual hierarchy

PubMed Central

Perry, Carolyn Jeane; Fallah, Mazyar

2014-01-01

The visual system is split into two processing streams: a ventral stream that receives color and form information and a dorsal stream that receives motion information. Each stream processes that information hierarchically, with each stage building upon the previous. In the ventral stream this leads to the formation of object representations that ultimately allow for object recognition regardless of changes in the surrounding environment. In the dorsal stream, this hierarchical processing has classically been thought to lead to the computation of complex motion in three dimensions. However, there is evidence to suggest that there is integration of both dorsal and ventral stream information into motion computation processes, giving rise to intermediate object representations, which facilitate object selection and decision making mechanisms in the dorsal stream. First we review the hierarchical processing of motion along the dorsal stream and the building up of object representations along the ventral stream. Then we discuss recent work on the integration of ventral and dorsal stream features that lead to intermediate object representations in the dorsal stream. Finally we propose a framework describing how and at what stage different features are integrated into dorsal visual stream object representations. Determining the integration of features along the dorsal stream is necessary to understand not only how the dorsal stream builds up an object representation but also which computations are performed on object representations instead of local features. PMID:25140147

Infrared spectroscopy for the determination of hydrocarbon types in jet fuels

NASA Technical Reports Server (NTRS)

Buchar, C. S.

1981-01-01

The concentration of hydrocarbon types in conventional jet fuels and synfuels can be measured using a computerized infrared spectrophotometer. The computerized spectrophotometer is calibrated using a fuel of known aromatic and olefinic content. Once calibration is completed, other fuels can be rapidly analyzed using an analytical program built into the computer. The concentration of saturates can be calculated as 100 percent minus the sum of the aromatic and olefinic concentrations. The analysis of a number of jet fuels produced an average standard deviation of 1.76 percent for aromatic types and one of 3.99 percent for olefinic types. Other substances such as oils and organic mixtures can be analyzed for their hydrocarbon content.

The IEA/ORAU Long-Term Global Energy- CO2 Model: Personal Computer Version A84PC

DOE Data Explorer

Edmonds, Jae A.; Reilly, John M.; Boden, Thomas A. [CDIAC; Reynolds, S. E. [CDIAC; Barns, D. W.

1995-01-01

The IBM A84PC version of the Edmonds-Reilly model has the capability to calculate both CO2 and CH4 emission estimates by source and region. Population, labor productivity, end-use energy efficiency, income effects, price effects, resource base, technological change in energy production, environmental costs of energy production, market-penetration rate of energy-supply technology, solar and biomass energy costs, synfuel costs, and the number of forecast periods may be interactively inspected and altered producing a variety of global and regional CO2 and CH4 emission scenarios for 1975 through 2100. Users are strongly encouraged to see our instructions for downloading, installing, and running the model.

Device for staged carbon monoxide oxidation

DOEpatents

Vanderborgh, Nicholas E.; Nguyen, Trung V.; Guante, Jr., Joseph

1993-01-01

A method and apparatus for selectively oxidizing carbon monoxide in a hydrogen rich feed stream. The method comprises mixing a feed stream consisting essentially of hydrogen, carbon dioxide, water and carbon monoxide with a first predetermined quantity of oxygen (air). The temperature of the mixed feed/oxygen stream is adjusted in a first the heat exchanger assembly (20) to a first temperature. The mixed feed/oxygen stream is sent to reaction chambers (30,32) having an oxidation catalyst contained therein. The carbon monoxide of the feed stream preferentially absorbs on the catalyst at the first temperature to react with the oxygen in the chambers (30,32) with minimal simultaneous reaction of the hydrogen to form an intermediate hydrogen rich process stream having a lower carbon monoxide content than the feed stream. The elevated outlet temperature of the process stream is carefully controlled in a second heat exchanger assembly (42) to a second temperature above the first temperature. The process stream is then mixed with a second predetermined quantity of oxygen (air). The carbon monoxide of the process stream preferentially reacts with the second quantity of oxygen in a second stage reaction chamber (56) with minimal simultaneous reaction of the hydrogen in the process stream. The reaction produces a hydrogen rich product stream having a lower carbon monoxide content than the process stream. The product stream is then cooled in a third heat exchanger assembly (72) to a third predetermined temperature. Three or more stages may be desirable, each with metered oxygen injection.

TERMINAL ELECTRON ACCEPTING PROCESSES IN THE ALLUVIAL SEDIMENTS OF A HEADWATER STREAM

EPA Science Inventory

Chemical fluxes between catchments and streams are influenced by biochemical processes in the groundwater-stream water (GW-SW) ecotone, the interface between stream surface water and groundwater. Terminal electron accepting processes (TEAPs) that are utilized in respiration of ...

Visual and visuomotor processing of hands and tools as a case study of cross talk between the dorsal and ventral streams.

PubMed

Almeida, Jorge; Amaral, Lénia; Garcea, Frank E; Aguiar de Sousa, Diana; Xu, Shan; Mahon, Bradford Z; Martins, Isabel Pavão

2018-05-24

A major principle of organization of the visual system is between a dorsal stream that processes visuomotor information and a ventral stream that supports object recognition. Most research has focused on dissociating processing across these two streams. Here we focus on how the two streams interact. We tested neurologically-intact and impaired participants in an object categorization task over two classes of objects that depend on processing within both streams-hands and tools. We measured how unconscious processing of images from one of these categories (e.g., tools) affects the recognition of images from the other category (i.e., hands). Our findings with neurologically-intact participants demonstrated that processing an image of a hand hampers the subsequent processing of an image of a tool, and vice versa. These results were not present in apraxic patients (N = 3). These findings suggest local and global inhibitory processes working in tandem to co-register information across the two streams.

Valve For Extracting Samples From A Process Stream

NASA Technical Reports Server (NTRS)

Callahan, Dave

1995-01-01

Valve for extracting samples from process stream includes cylindrical body bolted to pipe that contains stream. Opening in valve body matched and sealed against opening in pipe. Used to sample process streams in variety of facilities, including cement plants, plants that manufacture and reprocess plastics, oil refineries, and pipelines.

Particle dispersing system and method for testing semiconductor manufacturing equipment

DOEpatents

Chandrachood, Madhavi; Ghanayem, Steve G.; Cantwell, Nancy; Rader, Daniel J.; Geller, Anthony S.

1998-01-01

The system and method prepare a gas stream comprising particles at a known concentration using a particle disperser for moving particles from a reservoir of particles into a stream of flowing carrier gas. The electrostatic charges on the particles entrained in the carrier gas are then neutralized or otherwise altered, and the resulting particle-laden gas stream is then diluted to provide an acceptable particle concentration. The diluted gas stream is then split into a calibration stream and the desired output stream. The particles in the calibration stream are detected to provide an indication of the actual size distribution and concentration of particles in the output stream that is supplied to a process chamber being analyzed. Particles flowing out of the process chamber within a vacuum pumping system are detected, and the output particle size distribution and concentration are compared with the particle size distribution and concentration of the calibration stream in order to determine the particle transport characteristics of a process chamber, or to determine the number of particles lodged in the process chamber as a function of manufacturing process parameters such as pressure, flowrate, temperature, process chamber geometry, particle size, particle charge, and gas composition.

Coal combustion products: trash or treasure?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hansen, T.

2006-07-15

Coal combustion by-products can be a valuable resource to various industries. The American Coal Ash Association (ACAA) collects data on production and uses of coal combustion products (CCPs). 122.5 million tons of CCPs were produced in 2004. The article discusses the results of the ACCA's 2004 survey. Fly ash is predominantly used as a substitute for Portland cement; bottom ash for structural fill, embankments and paved road cases. Synthetic gypsum from the FGD process is commonly used in wallboard. Plant owners are only likely to have a buyer for a portion of their CCPs. Although sale of hot water (frommore » Antelope Valley Station) from condensers for use in a fish farm to raise tilapia proved unviable, the Great Plains Synfuels Plant which manufactures natural gas from lignite produces a wide range of products including anhydrous ammonia, phenol, krypton, carbon dioxide (for enhanced oil recovery), tar oils and liquid nitrogen. ACCA's goal is to educate people about CCPs and how to make them into useful products, and market them, in order to reduce waste disposal and enhance revenue. The article lists members of the ACCA. 2 photos., 1 tab.« less

Evaluating the Effects of Culvert Designs on Ecosystem Processes in Northern Wisconsin Streams

Treesearch

J. C. Olson; A. M. Marcarelli; A.L. Timm; S.L. Eggert; R.K. Kolka

2017-01-01

Culvert replacements are commonly undertaken to restore aquatic organism passage and stream hydrologic and geomorphic conditions, but their effects on ecosystem processes are rarely quantified. The objective of this study was to investigate the effects of two culvert replacement designs on stream ecosystem processes. The stream simulation design, where culverts...

Apparatus and process for the refrigeration, liquefaction and separation of gases with varying levels of purity

DOEpatents

Bingham, Dennis N.; Wilding, Bruce M.; McKellar, Michael G.

2002-01-01

A process for the separation and liquefaction of component gasses from a pressurized mix gas stream is disclosed. The process involves cooling the pressurized mixed gas stream in a heat exchanger so as to condensing one or more of the gas components having the highest condensation point; separating the condensed components from the remaining mixed gas stream in a gas-liquid separator; cooling the separated condensed component stream by passing it through an expander; and passing the cooled component stream back through the heat exchanger such that the cooled component stream functions as the refrigerant for the heat exchanger. The cycle is then repeated for the remaining mixed gas stream so as to draw off the next component gas and further cool the remaining mixed gas stream. The process continues until all of the component gases are separated from the desired gas stream. The final gas stream is then passed through a final heat exchanger and expander. The expander decreases the pressure on the gas stream, thereby cooling the stream and causing a portion of the gas stream to liquify within a tank. The portion of the gas which is hot liquefied is passed back through each of the heat exchanges where it functions as a refrigerant.

Apparatus and process for the refrigeration, liquefaction and separation of gases with varying levels of purity

DOEpatents

Bingham, Dennis N.; Wilding, Bruce M.; McKellar, Michael G.

2000-01-01

A process for the separation and liquefaction of component gasses from a pressurized mix gas stream is disclosed. The process involves cooling the pressurized mixed gas stream in a heat exchanger so as to condense one or more of the gas components having the highest condensation point; separating the condensed components from the remaining mixed gas stream in a gas-liquid separator; cooling the separated condensed component stream by passing it through an expander; and passing the cooled component stream back through the heat exchanger such that the cooled component stream functions as the refrigerant for the heat exchanger. The cycle is then repeated for the remaining mixed gas stream so as to draw off the next component gas and further cool the remaining mixed gas stream. The process continues until all of the component gases are separated from the desired gas stream. The final gas stream is then passed through a final heat exchanger and expander. The expander decreases the pressure on the gas stream, thereby cooling the stream and causing a portion of the gas stream to liquify within a tank. The portion of the gas which is not liquefied is passed back through each of the heat exchanges where it functions as a refrigerant.

Apparatus for the liquefaction of natural gas and methods relating to same

DOEpatents

Turner, Terry D [Ammon, ID; Wilding, Bruce M [Idaho Falls, ID; McKellar, Michael G [Idaho Falls, ID

2009-09-22

An apparatus and method for producing liquefied natural gas. A liquefaction plant may be coupled to a source of unpurified natural gas, such as a natural gas pipeline at a pressure letdown station. A portion of the gas is drawn off and split into a process stream and a cooling stream. The cooling stream passes through an expander creating work output. A compressor may be driven by the work output and compresses the process stream. The compressed process stream is cooled, such as by the expanded cooling stream. The cooled, compressed process stream is expanded to liquefy the natural gas. A gas-liquid separator separates a vapor from the liquid natural gas. A portion of the liquid gas is used for additional cooling. Gas produced within the system may be recompressed for reintroduction into a receiving line or recirculation within the system for further processing.

Forecast of Future Aviation Fuels. Part 1: Scenarios

NASA Technical Reports Server (NTRS)

English, J. M.; Liu, C. Y.; Smith, J. L.; Yin, A. K. K.; Pan, G. A.; Ayati, M. B.; Gyamfi, M.; Arabzadah, M. R.

1978-01-01

A preliminary set of scenarios is described for depicting the air transport industry as it grows and changes, up to the year 2025. This provides the background for predicting the needs for future aviation fuels to meet the requirements of the industry as new basic sources, such as oil shale and coal, which are utilized to supplement petroleum. Five scenarios are written to encompass a range of futures from a serious resource-constrained economy to a continuous and optimistic economic growth. A unique feature is the choice of one immediate range scenario which is based on a serious interruption of economic growth occasioned by an energy shortfall. This is presumed to occur due to lags in starting a synfuels program.

Dual-stream modulation failure: a novel hypothesis for the formation and maintenance of delusions in schizophrenia.

PubMed

Speechley, William J; Ngan, Elton T C

2008-01-01

Delusions, a cardinal feature of schizophrenia, are characterized by the development and preservation of false beliefs despite reason and evidence to the contrary. A number of cognitive models have made important contributions to our understanding of delusions, though it remains unclear which core cognitive processes are malfunctioning to enable individuals with delusions to form and maintain erroneous beliefs. We propose a modified dual-stream processing model that provides a viable and testable mechanism that can account for this debilitating symptom. Dual-stream models divide decision-making into two streams: a fast, intuitive and automatic form of processing (Stream 1); and a slower, conscious and deliberative process (Stream 2). Our novel model proposes two key influences on the way these streams interact in everyday decision-making: conflict and emotion. Conflict: in most decision-making scenarios one obvious answer presents itself and the two streams converge onto the same conclusion. However, in instances where there are competing alternative possibilities, an individual often experiences dissonance, or a sense of conflict. The detection of this conflict biases processing towards the more deliberative Stream 2. Emotion: highly emotional states can result in behavior that is reflexive and action-oriented. This may be due to the power of emotionally valenced stimuli to bias reasoning towards Stream 1. We propose that in schizophrenia, an abnormal response to these two influences results in a pathological schism between Stream 1 and Stream 2, enabling erroneous intuitive explanations to coexist with contrary logical explanations of the same event. Specifically, we suggest that delusions are the result of a failure to reconcile the two streams due to both a failure of conflict to bias decision-making towards Stream 2 and an accentuated emotional bias towards Stream 1.

Using high-frequency nitrogen and carbon measurements to decouple temporal dynamics of catchment and in-stream transport and reaction processes in a headwater stream

NASA Astrophysics Data System (ADS)

Blaen, P.; Riml, J.; Khamis, K.; Krause, S.

2017-12-01

Within river catchments across the world, headwater streams represent important sites of nutrient transformation and uptake due to their high rates of microbial community processing and relative abundance in the landscape. However, separating the combined influence of in-stream transport and reaction processes from the overall catchment response can be difficult due to spatio-temporal variability in nutrient and organic matter inputs, flow regimes, and reaction rates. Recent developments in optical sensor technologies enable high-frequency, in situ nutrient measurements, and thus provide opportunities for greater insights into in-stream processes. Here, we use in-stream observations of hourly nitrate (NO3-N), dissolved organic carbon (DOC) and dissolved oxygen (DO) measurements from paired in situ sensors that bound a 1 km headwater stream reach in a mixed-use catchment in central England. We employ a spectral approach to decompose (1) variances in solute loading from the surrounding landscape, and (2) variances in reach-scale in-stream nutrient transport and reaction processes. In addition, we estimate continuous rates of reach-scale NO3-N and DOC assimilation/dissimilation, ecosystem respiration and primary production. Comparison of these results over a range of hydrological conditions (baseflow, variable storm events) and timescales (event-based, diel, seasonal) facilitates new insights into the physical and biogeochemical processes that drive in-stream nutrient dynamics in headwater streams.

Separation process using pervaporation and dephlegmation

DOEpatents

Vane, Leland M.; Mairal, Anurag P.; Ng, Alvin; Alvarez, Franklin R.; Baker, Richard W.

2004-06-29

A process for treating liquids containing organic compounds and water. The process includes a pervaporation step in conjunction with a dephlegmation step to treat at least a portion of the permeate vapor from the pervaporation step. The process yields a membrane residue stream, a stream enriched in the more volatile component (usually the organic) as the overhead stream from the dephlegmator and a condensate stream enriched in the less volatile component (usually the water) as a bottoms stream from the dephlegmator. Any of these may be the principal product of the process. The membrane separation step may also be performed in the vapor phase, or by membrane distillation.

A failure of conflict to modulate dual-stream processing may underlie the formation and maintenance of delusions.

PubMed

Speechley, W J; Murray, C B; McKay, R M; Munz, M T; Ngan, E T C

2010-03-01

Dual-stream information processing proposes that reasoning is composed of two interacting processes: a fast, intuitive system (Stream 1) and a slower, more logical process (Stream 2). In non-patient controls, divergence of these streams may result in the experience of conflict, modulating decision-making towards Stream 2, and initiating a more thorough examination of the available evidence. In delusional schizophrenia patients, a failure of conflict to modulate decision-making towards Stream 2 may reduce the influence of contradictory evidence, resulting in a failure to correct erroneous beliefs. Delusional schizophrenia patients and non-patient controls completed a deductive reasoning task requiring logical validity judgments of two-part conditional statements. Half of the statements were characterized by a conflict between logical validity (Stream 2) and content believability (Stream 1). Patients were significantly worse than controls in determining the logical validity of both conflict and non-conflict conditional statements. This between groups difference was significantly greater for the conflict condition. The results are consistent with the hypothesis that delusional schizophrenia patients fail to use conflict to modulate towards Stream 2 when the two streams of reasoning arrive at incompatible judgments. This finding provides encouraging preliminary support for the Dual-Stream Modulation Failure model of delusion formation and maintenance. 2009 Elsevier Masson SAS. All rights reserved.

Process for recovering organic components from liquid streams

DOEpatents

Blume, Ingo; Baker, Richard W.

1991-01-01

A separation process for recovering organic components from liquid streams. The process is a combination of pervaporation and decantation. In cases where the liquid stream contains the organic to be separated in dissolved form, the pervaporation step is used to concentrate the organic to a point above the solubility limit, so that a two-phase permeate is formed and then decanted. In cases where the liquid stream is a two-phase mixture, the decantation step is performed first, to remove the organic product phase, and the residue from the decanter is then treated by pervaporation. The condensed permeate from the pervaporation unit is sufficiently concentrated in the organic component to be fed back to the decanter. The process can be tailored to produce only two streams: an essentially pure organic product stream suitable for reuse, and a residue stream for discharge or reuse.

Methods of producing alkylated hydrocarbons from an in situ heat treatment process liquid

DOEpatents

Roes, Augustinus Wilhelmus Maria [Houston, TX; Mo, Weijian [Sugar Land, TX; Muylle, Michel Serge Marie [Houston, TX; Mandema, Remco Hugo [Houston, TX; Nair, Vijay [Katy, TX

2009-09-01

A method for producing alkylated hydrocarbons is disclosed. Formation fluid is produced from a subsurface in situ heat treatment process. The formation fluid is separated to produce a liquid stream and a first gas stream. The first gas stream includes olefins. The liquid stream is fractionated to produce at least a second gas stream including hydrocarbons having a carbon number of at least 3. The first gas stream and the second gas stream are introduced into an alkylation unit to produce alkylated hydrocarbons. At least a portion of the olefins in the first gas stream enhance alkylation.

Potential for real-time understanding of coupled hydrologic and biogeochemical processes in stream ecosystems: Future integration of telemetered data with process models for glacial meltwater streams

NASA Astrophysics Data System (ADS)

McKnight, Diane M.; Cozzetto, Karen; Cullis, James D. S.; Gooseff, Michael N.; Jaros, Christopher; Koch, Joshua C.; Lyons, W. Berry; Neupauer, Roseanna; Wlostowski, Adam

2015-08-01

While continuous monitoring of streamflow and temperature has been common for some time, there is great potential to expand continuous monitoring to include water quality parameters such as nutrients, turbidity, oxygen, and dissolved organic material. In many systems, distinguishing between watershed and stream ecosystem controls can be challenging. The usefulness of such monitoring can be enhanced by the application of quantitative models to interpret observed patterns in real time. Examples are discussed primarily from the glacial meltwater streams of the McMurdo Dry Valleys, Antarctica. Although the Dry Valley landscape is barren of plants, many streams harbor thriving cyanobacterial mats. Whereas a daily cycle of streamflow is controlled by the surface energy balance on the glaciers and the temporal pattern of solar exposure, the daily signal for biogeochemical processes controlling water quality is generated along the stream. These features result in an excellent outdoor laboratory for investigating fundamental ecosystem process and the development and validation of process-based models. As part of the McMurdo Dry Valleys Long-Term Ecological Research project, we have conducted field experiments and developed coupled biogeochemical transport models for the role of hyporheic exchange in controlling weathering reactions, microbial nitrogen cycling, and stream temperature regulation. We have adapted modeling approaches from sediment transport to understand mobilization of stream biomass with increasing flows. These models help to elucidate the role of in-stream processes in systems where watershed processes also contribute to observed patterns, and may serve as a test case for applying real-time stream ecosystem models.

Application of the Hydroecological Integrity Assessment Process for Missouri Streams

USGS Publications Warehouse

Kennen, Jonathan G.; Henriksen, James A.; Heasley, John; Cade, Brian S.; Terrell, James W.

2009-01-01

Natural flow regime concepts and theories have established the justification for maintaining or restoring the range of natural hydrologic variability so that physiochemical processes, native biodiversity, and the evolutionary potential of aquatic and riparian assemblages can be sustained. A synthesis of recent research advances in hydroecology, coupled with stream classification using hydroecologically relevant indices, has produced the Hydroecological Integrity Assessment Process (HIP). HIP consists of (1) a regional classification of streams into hydrologic stream types based on flow data from long-term gaging-station records for relatively unmodified streams, (2) an identification of stream-type specific indices that address 11 subcomponents of the flow regime, (3) an ability to establish environmental flow standards, (4) an evaluation of hydrologic alteration, and (5) a capacity to conduct alternative analyses. The process starts with the identification of a hydrologic baseline (reference condition) for selected locations, uses flow data from a stream-gage network, and proceeds to classify streams into hydrologic stream types. Concurrently, the analysis identifies a set of non-redundant and ecologically relevant hydrologic indices for 11 subcomponents of flow for each stream type. Furthermore, regional hydrologic models for synthesizing flow conditions across a region and the development of flow-ecology response relations for each stream type can be added to further enhance the process. The application of HIP to Missouri streams identified five stream types ((1) intermittent, (2) perennial runoff-flashy, (3) perennial runoff-moderate baseflow, (4) perennial groundwater-stable, and (5) perennial groundwater-super stable). Two Missouri-specific computer software programs were developed: (1) a Missouri Hydrologic Assessment Tool (MOHAT) which is used to establish a hydrologic baseline, provide options for setting environmental flow standards, and compare past and proposed hydrologic alterations; and (2) a Missouri Stream Classification Tool (MOSCT) designed for placing previously unclassified streams into one of the five pre-defined stream types.

Stream dynamics: An overview for land managers

Treesearch

Burchard H. Heede

1980-01-01

Concepts of stream dynamics are demonstrated through discussion of processes and process indicators; theory is included only where helpful to explain concepts. Present knowledge allows only qualitative prediction of stream behavior. However, such predictions show how management actions will affect the stream and its environment.

Leaf litter processing in West Virginia mountain streams: effects of temperature and stream chemistry

Treesearch

Jacquelyn M. Rowe; William B. Perry; Sue A. Perry

1996-01-01

Climate change has the potential to alter detrital processing in headwater streams, which receive the majority of their nutrient input as terrestrial leaf litter. Early placement of experimental leaf packs in streams, one month prior to most abscission, was used as an experimental manipulation to increase stream temperature during leaf pack breakdown. We studied leaf...

Riparian communities associated with pacific northwest headwater streams: assemblages, processes, and uniqueness.

Treesearch

John S. Richardson; Robert J. Naiman; Frederick J. Swanson; David E. Hibbs

2005-01-01

Riparian areas of large streams provide important habitat to many species and control many instream processes - but is the same true for the margins of small streams? This review considers riparian areas alongside small streams in forested, mountainous areas of the Pacific Northwest and asks if there are fundamental ecological differences from larger streams and from...

Functional Process Zones Characterizing Aquatic Insect Communities in Streams of the Brazilian Cerrado.

PubMed

Godoy, B S; Simião-Ferreira, J; Lodi, S; Oliveira, L G

2016-04-01

Stream ecology studies see to understand ecological dynamics in lotic systems. The characterization of streams into Functional Process Zones (FPZ) has been currently debated in stream ecology because aquatic communities respond to functional processes of river segments. Therefore, we tested if different functional process zones have different number of genera and trophic structure using the aquatic insect community of Neotropical streams. We also assessed whether using physical and chemical variables may complement the approach of using FPZ to model communities of aquatic insects in Cerrado streams. This study was conducted in 101 streams or rivers from the central region of the state of Goiás, Brazil. We grouped the streams into six FPZ associated to size of the river system, presence of riparian forest, and riverbed heterogeneity. We used Bayesian models to compare number of genera and relative frequency of the feeding groups between FPZs. Streams classified in different FPZs had a different number of genera, and the largest and best preserved rivers had an average of four additional genera. Trophic structure exhibited low variability among FPZs, with little difference both in the number of genera and in abundance. Using functional process zones in Cerrado streams yielded good results for Ephemeroptera, Plecoptera, and Trichoptera communities. Thus, species distribution and community structure in the river basin account for functional processes and not necessarily for the position of the community along a longitudinal dimension of the lotic system.

The chemistry of iron, aluminum, and dissolved organic material in three acidic, metal-enriched, mountain streams, as controlled by watershed and in-stream processes

USGS Publications Warehouse

McKnight, Diane M.; Bencala, Kenneth E.

1990-01-01

Several studies were conducted in three acidic, metal-enriched, mountain streams, and the results are discussed together in this paper to provide a synthesis of watershed and in-stream processes controlling Fe, Al, and DOC (dissolved organic carbon) concentrations. One of the streams, the Snake River, is naturally acidic; the other two, Peru Creek and St. Kevin Gulch, receive acid mine drainage. Analysis of stream water chemistry data for the acidic headwaters of the Snake River shows that some trace metal solutes (Al, Mn, Zn) are correlated with major ions, indicating that watershed processes control their concentrations. Once in the stream, biogeochemical processes can control transport if they occur over time scales comparable to those for hydrologic transport. Examples of the following in-stream reactions are presented: (1) photoreduction and dissolution of hydrous iron oxides in response to an experimental decrease in stream pH, (2) precipitation of Al at three stream confluences, and (3) sorption of dissolved organic material by hydrous iron and aluminum oxides in a stream confluence. The extent of these reactions is evaluated using conservative tracers and a transport model that includes storage in the substream zone.

Apparatus for the liquefaction of a gas and methods relating to same

DOEpatents

Turner, Terry D [Idaho Falls, ID; Wilding, Bruce M [Idaho Falls, ID; McKellar, Michael G [Idaho Falls, ID

2009-12-29

Apparatuses and methods are provided for producing liquefied gas, such as liquefied natural gas. In one embodiment, a liquefaction plant may be coupled to a source of unpurified natural gas, such as a natural gas pipeline at a pressure letdown station. A portion of the gas is drawn off and split into a process stream and a cooling stream. The cooling stream may be sequentially pass through a compressor and an expander. The process stream may also pass through a compressor. The compressed process stream is cooled, such as by the expanded cooling stream. The cooled, compressed process stream is expanded to liquefy the natural gas. A gas-liquid separator separates the vapor from the liquid natural gas. A portion of the liquid gas may be used for additional cooling. Gas produced within the system may be recompressed for reintroduction into a receiving line.

Revealing the dual streams of speech processing.

PubMed

Fridriksson, Julius; Yourganov, Grigori; Bonilha, Leonardo; Basilakos, Alexandra; Den Ouden, Dirk-Bart; Rorden, Christopher

2016-12-27

Several dual route models of human speech processing have been proposed suggesting a large-scale anatomical division between cortical regions that support motor-phonological aspects vs. lexical-semantic aspects of speech processing. However, to date, there is no complete agreement on what areas subserve each route or the nature of interactions across these routes that enables human speech processing. Relying on an extensive behavioral and neuroimaging assessment of a large sample of stroke survivors, we used a data-driven approach using principal components analysis of lesion-symptom mapping to identify brain regions crucial for performance on clusters of behavioral tasks without a priori separation into task types. Distinct anatomical boundaries were revealed between a dorsal frontoparietal stream and a ventral temporal-frontal stream associated with separate components. Collapsing over the tasks primarily supported by these streams, we characterize the dorsal stream as a form-to-articulation pathway and the ventral stream as a form-to-meaning pathway. This characterization of the division in the data reflects both the overlap between tasks supported by the two streams as well as the observation that there is a bias for phonological production tasks supported by the dorsal stream and lexical-semantic comprehension tasks supported by the ventral stream. As such, our findings show a division between two processing routes that underlie human speech processing and provide an empirical foundation for studying potential computational differences that distinguish between the two routes.

Hamming and Accumulator Codes Concatenated with MPSK or QAM

NASA Technical Reports Server (NTRS)

Divsalar, Dariush; Dolinar, Samuel

2009-01-01

In a proposed coding-and-modulation scheme, a high-rate binary data stream would be processed as follows: 1. The input bit stream would be demultiplexed into multiple bit streams. 2. The multiple bit streams would be processed simultaneously into a high-rate outer Hamming code that would comprise multiple short constituent Hamming codes a distinct constituent Hamming code for each stream. 3. The streams would be interleaved. The interleaver would have a block structure that would facilitate parallelization for high-speed decoding. 4. The interleaved streams would be further processed simultaneously into an inner two-state, rate-1 accumulator code that would comprise multiple constituent accumulator codes - a distinct accumulator code for each stream. 5. The resulting bit streams would be mapped into symbols to be transmitted by use of a higher-order modulation - for example, M-ary phase-shift keying (MPSK) or quadrature amplitude modulation (QAM). The novelty of the scheme lies in the concatenation of the multiple-constituent Hamming and accumulator codes and the corresponding parallel architectures of the encoder and decoder circuitry (see figure) needed to process the multiple bit streams simultaneously. As in the cases of other parallel-processing schemes, one advantage of this scheme is that the overall data rate could be much greater than the data rate of each encoder and decoder stream and, hence, the encoder and decoder could handle data at an overall rate beyond the capability of the individual encoder and decoder circuits.

Optimized heat exchange in a CO2 de-sublimation process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baxter, Larry; Terrien, Paul; Tessier, Pascal

The present invention is a process for removing carbon dioxide from a compressed gas stream including cooling the compressed gas in a first heat exchanger, introducing the cooled gas into a de-sublimating heat exchanger, thereby producing a first solid carbon dioxide stream and a first carbon dioxide poor gas stream, expanding the carbon dioxide poor gas stream, thereby producing a second solid carbon dioxide stream and a second carbon dioxide poor gas stream, combining the first solid carbon dioxide stream and the second solid carbon dioxide stream, thereby producing a combined solid carbon dioxide stream, and indirectly exchanging heat betweenmore » the combined solid carbon dioxide stream and the compressed gas in the first heat exchanger.« less

Structures linking physical and biological processes in headwater streams of the Maybeso watershed, Southeast Alaska

Treesearch

Mason D. Bryant; Takashi Gomi; Jack J. Piccolo

2007-01-01

We focus on headwater streams originating in the mountainous terrain of northern temperate rain forests. These streams rapidly descend from gradients greater than 20% to less than 5% in U-shaped glacial valleys. We use a set of studies on headwater streams in southeast Alaska to define headwater stream catchments, link physical and biological processes, and describe...

Treatment of gas from an in situ conversion process

DOEpatents

Diaz, Zaida [Katy, TX; Del Paggio, Alan Anthony [Spring, TX; Nair, Vijay [Katy, TX; Roes, Augustinus Wilhelmus Maria [Houston, TX

2011-12-06

A method of producing methane is described. The method includes providing formation fluid from a subsurface in situ conversion process. The formation fluid is separated to produce a liquid stream and a first gas stream. The first gas stream includes olefins. At least the olefins in the first gas stream are contacted with a hydrogen source in the presence of one or more catalysts and steam to produce a second gas stream. The second gas stream is contacted with a hydrogen source in the presence of one or more additional catalysts to produce a third gas stream. The third gas stream includes methane.

Aqueous stream characterization from biomass fast pyrolysis and catalytic fast pyrolysis

DOE PAGES

Black, Brenna A.; Michener, William E.; Ramirez, Kelsey J.; ...

2016-09-05

Here, biomass pyrolysis offers a promising means to rapidly depolymerize lignocellulosic biomass for subsequent catalytic upgrading to renewable fuels. Substantial efforts are currently ongoing to optimize pyrolysis processes including various fast pyrolysis and catalytic fast pyrolysis schemes. In all cases, complex aqueous streams are generated containing solubilized organic compounds that are not converted to target fuels or chemicals and are often slated for wastewater treatment, in turn creating an economic burden on the biorefinery. Valorization of the species in these aqueous streams, however, offers significant potential for substantially improving the economics and sustainability of thermochemical biorefineries. To that end, heremore » we provide a thorough characterization of the aqueous streams from four pilot-scale pyrolysis processes: namely, from fast pyrolysis, fast pyrolysis with downstream fractionation, in situ catalytic fast pyrolysis, and ex situ catalytic fast pyrolysis. These configurations and processes represent characteristic pyrolysis processes undergoing intense development currently. Using a comprehensive suite of aqueous-compatible analytical techniques, we quantitatively characterize between 12 g kg -1 of organic carbon of a highly aqueous catalytic fast pyrolysis stream and up to 315 g kg -1 of organic carbon present in the fast pyrolysis aqueous streams. In all cases, the analysis ranges between 75 and 100% of mass closure. The composition and stream properties closely match the nature of pyrolysis processes, with high contents of carbohydrate-derived compounds in the fast pyrolysis aqueous phase, high acid content in nearly all streams, and mostly recalcitrant phenolics in the heavily deoxygenated ex situ catalytic fast pyrolysis stream. Overall, this work provides a detailed compositional analysis of aqueous streams from leading thermochemical processes -- analyses that are critical for subsequent development of selective valorization strategies for these waste streams.« less

Aqueous stream characterization from biomass fast pyrolysis and catalytic fast pyrolysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Black, Brenna A.; Michener, William E.; Ramirez, Kelsey J.

Here, biomass pyrolysis offers a promising means to rapidly depolymerize lignocellulosic biomass for subsequent catalytic upgrading to renewable fuels. Substantial efforts are currently ongoing to optimize pyrolysis processes including various fast pyrolysis and catalytic fast pyrolysis schemes. In all cases, complex aqueous streams are generated containing solubilized organic compounds that are not converted to target fuels or chemicals and are often slated for wastewater treatment, in turn creating an economic burden on the biorefinery. Valorization of the species in these aqueous streams, however, offers significant potential for substantially improving the economics and sustainability of thermochemical biorefineries. To that end, heremore » we provide a thorough characterization of the aqueous streams from four pilot-scale pyrolysis processes: namely, from fast pyrolysis, fast pyrolysis with downstream fractionation, in situ catalytic fast pyrolysis, and ex situ catalytic fast pyrolysis. These configurations and processes represent characteristic pyrolysis processes undergoing intense development currently. Using a comprehensive suite of aqueous-compatible analytical techniques, we quantitatively characterize between 12 g kg -1 of organic carbon of a highly aqueous catalytic fast pyrolysis stream and up to 315 g kg -1 of organic carbon present in the fast pyrolysis aqueous streams. In all cases, the analysis ranges between 75 and 100% of mass closure. The composition and stream properties closely match the nature of pyrolysis processes, with high contents of carbohydrate-derived compounds in the fast pyrolysis aqueous phase, high acid content in nearly all streams, and mostly recalcitrant phenolics in the heavily deoxygenated ex situ catalytic fast pyrolysis stream. Overall, this work provides a detailed compositional analysis of aqueous streams from leading thermochemical processes -- analyses that are critical for subsequent development of selective valorization strategies for these waste streams.« less

Quantitative measurement of stream respiration using the resazurin-resorufin system

NASA Astrophysics Data System (ADS)

Gonzalez Pinzon, R. A.; Acker, S.; Haggerty, R.; Myrold, D.

2011-12-01

After three decades of active research in hydrology and stream ecology, the relationship between stream solute transport, metabolism and nutrient dynamics is still unresolved. These knowledge gaps obscure the function of stream ecosystems and how they interact with other landscape processes. To date, measuring rates of stream metabolism is accomplished with techniques that have vast uncertainties and are not spatially representative. These limitations mask the role of metabolism in nutrient processing. Clearly, more robust techniques are needed to develop mechanistic relationships that will ultimately improve our fundamental understanding of in-stream processes and how streams interact with other ecosystems. We investigated the "metabolic window of detection" of the Resazurin (Raz)-Resorufin (Rru) system (Haggerty et al., 2008, 2009). Although previous results have shown that the transformation of Raz to Rru is strongly correlated with respiration, a quantitative relationship between them is needed. We investigated this relationship using batch experiments with pure cultures (aerobic and anaerobic) and flow-through columns with incubated sediments from four different streams. The results suggest that the Raz-Rru system is a suitable approach that will enable hydrologists and stream ecologists to measure in situ and in vivo respiration at different scales, thus opening a reliable alternative to investigate how solute transport and stream metabolism control nutrient processing.

Modeling nutrient retention at the watershed scale: Does small stream research apply to the whole river network?

NASA Astrophysics Data System (ADS)

Aguilera, Rosana; Marcé, Rafael; Sabater, Sergi

2013-06-01

are conveyed from terrestrial and upstream sources through drainage networks. Streams and rivers contribute to regulate the material exported downstream by means of transformation, storage, and removal of nutrients. It has been recently suggested that the efficiency of process rates relative to available nutrient concentration in streams eventually declines, following an efficiency loss (EL) dynamics. However, most of these predictions are based at the reach scale in pristine streams, failing to describe the role of entire river networks. Models provide the means to study nutrient cycling from the stream network perspective via upscaling to the watershed the key mechanisms occurring at the reach scale. We applied a hybrid process-based and statistical model (SPARROW, Spatially Referenced Regression on Watershed Attributes) as a heuristic approach to describe in-stream nutrient processes in a highly impaired, high stream order watershed (the Llobregat River Basin, NE Spain). The in-stream decay specifications of the model were modified to include a partial saturation effect in uptake efficiency (expressed as a power law) and better capture biological nutrient retention in river systems under high anthropogenic stress. The stream decay coefficients were statistically significant in both nitrate and phosphate models, indicating the potential role of in-stream processing in limiting nutrient export. However, the EL concept did not reliably describe the patterns of nutrient uptake efficiency for the concentration gradient and streamflow values found in the Llobregat River basin, posing in doubt its complete applicability to explain nutrient retention processes in stream networks comprising highly impaired rivers.

Pervaporation process and use in treating waste stream from glycol dehydrator

DOEpatents

Kaschemekat, Jurgen; Baker, Richard W.

1994-01-01

Pervaporation processes and apparatus with few moving parts. Ideally, only one pump is used to provide essentially all of the motive power and driving force needed. The process is particularly useful for handling small streams with flow rates less than about 700 gpd. Specifically, the process can be used to treat waste streams from glycol dehydrator regeneration units.

Current and potential uses of bioactive molecules from marine processing waste.

PubMed

Suleria, Hafiz Ansar Rasul; Masci, Paul; Gobe, Glenda; Osborne, Simone

2016-03-15

Food industries produce huge amounts of processing waste that are often disposed of incurring expenses and impacting upon the environment. For these and other reasons, food processing waste streams, in particular marine processing waste streams, are gaining popularity amongst pharmaceutical, cosmetic and nutraceutical industries as sources of bioactive molecules. In the last 30 years, there has been a gradual increase in processed marine products with a concomitant increase in waste streams that include viscera, heads, skins, fins, bones, trimmings and shellfish waste. In 2010, these waste streams equated to approximately 24 million tonnes of mostly unused resources. Marine processing waste streams not only represent an abundant resource, they are also enriched with structurally diverse molecules that possess a broad panel of bioactivities including anti-oxidant, anti-coagulant, anti-thrombotic, anti-cancer and immune-stimulatory activities. Retrieval and characterisation of bioactive molecules from marine processing waste also contributes valuable information to the vast field of marine natural product discovery. This review summarises the current use of bioactive molecules from marine processing waste in different products and industries. Moreover, this review summarises new research into processing waste streams and the potential for adoption by industries in the creation of new products containing marine processing waste bioactives. © 2015 Society of Chemical Industry.

Flow directionality, mountain barriers and functional traits determine diatom metacommunity structuring of high mountain streams.

PubMed

Dong, Xiaoyu; Li, Bin; He, Fengzhi; Gu, Yuan; Sun, Meiqin; Zhang, Haomiao; Tan, Lu; Xiao, Wen; Liu, Shuoran; Cai, Qinghua

2016-04-19

Stream metacommunities are structured by a combination of local (environmental filtering) and regional (dispersal) processes. The unique characters of high mountain streams could potentially determine metacommunity structuring, which is currently poorly understood. Aiming at understanding how these characters influenced metacommunity structuring, we explored the relative importance of local environmental conditions and various dispersal processes, including through geographical (overland), topographical (across mountain barriers) and network (along flow direction) pathways in shaping benthic diatom communities. From a trait perspective, diatoms were categorized into high-profile, low-profile and motile guild to examine the roles of functional traits. Our results indicated that both environmental filtering and dispersal processes influenced metacommunity structuring, with dispersal contributing more than environmental processes. Among the three pathways, stream corridors were primary pathway. Deconstructive analysis suggested different responses to environmental and spatial factors for each of three ecological guilds. However, regardless of traits, dispersal among streams was limited by mountain barriers, while dispersal along stream was promoted by rushing flow in high mountain stream. Our results highlighted that directional processes had prevailing effects on metacommunity structuring in high mountain streams. Flow directionality, mountain barriers and ecological guilds contributed to a better understanding of the roles that mountains played in structuring metacommunity.

Chromium: A Stress-Processing Framework for Interactive Rendering on Clusters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Humphreys, G,; Houston, M.; Ng, Y.-R.

2002-01-11

We describe Chromium, a system for manipulating streams of graphics API commands on clusters of workstations. Chromium's stream filters can be arranged to create sort-first and sort-last parallel graphics architectures that, in many cases, support the same applications while using only commodity graphics accelerators. In addition, these stream filters can be extended programmatically, allowing the user to customize the stream transformations performed by nodes in a cluster. Because our stream processing mechanism is completely general, any cluster-parallel rendering algorithm can be either implemented on top of or embedded in Chromium. In this paper, we give examples of real-world applications thatmore » use Chromium to achieve good scalability on clusters of workstations, and describe other potential uses of this stream processing technology. By completely abstracting the underlying graphics architecture, network topology, and API command processing semantics, we allow a variety of applications to run in different environments.« less

Mass, energy and material balances of SRF production process. Part 1: SRF produced from commercial and industrial waste.

PubMed

Nasrullah, Muhammad; Vainikka, Pasi; Hannula, Janne; Hurme, Markku; Kärki, Janne

2014-08-01

This paper presents the mass, energy and material balances of a solid recovered fuel (SRF) production process. The SRF is produced from commercial and industrial waste (C&IW) through mechanical treatment (MT). In this work various streams of material produced in SRF production process are analyzed for their proximate and ultimate analysis. Based on this analysis and composition of process streams their mass, energy and material balances are established for SRF production process. Here mass balance describes the overall mass flow of input waste material in the various output streams, whereas material balance describes the mass flow of components of input waste stream (such as paper and cardboard, wood, plastic (soft), plastic (hard), textile and rubber) in the various output streams of SRF production process. A commercial scale experimental campaign was conducted on an MT waste sorting plant to produce SRF from C&IW. All the process streams (input and output) produced in this MT plant were sampled and treated according to the CEN standard methods for SRF: EN 15442 and EN 15443. The results from the mass balance of SRF production process showed that of the total input C&IW material to MT waste sorting plant, 62% was recovered in the form of SRF, 4% as ferrous metal, 1% as non-ferrous metal and 21% was sorted out as reject material, 11.6% as fine fraction, and 0.4% as heavy fraction. The energy flow balance in various process streams of this SRF production process showed that of the total input energy content of C&IW to MT plant, 75% energy was recovered in the form of SRF, 20% belonged to the reject material stream and rest 5% belonged with the streams of fine fraction and heavy fraction. In the material balances, mass fractions of plastic (soft), plastic (hard), paper and cardboard and wood recovered in the SRF stream were 88%, 70%, 72% and 60% respectively of their input masses to MT plant. A high mass fraction of plastic (PVC), rubber material and non-combustibles (such as stone/rock and glass particles), was found in the reject material stream. Copyright © 2014 Elsevier Ltd. All rights reserved.

40 CFR 63.138 - Process wastewater provisions-performance standards for treatment processes managing Group 1...

Code of Federal Regulations, 2012 CFR

2012-07-01

... each treatment process. (b) Control options: Group 1 wastewater streams for Table 9 compounds. The... section. (c) Control options: Group 1 wastewater streams for Table 8 compounds. The owner or operator...) Residuals. For each residual removed from a Group 1 wastewater stream, the owner or operator shall control...

40 CFR 63.138 - Process wastewater provisions-performance standards for treatment processes managing Group 1...

Code of Federal Regulations, 2013 CFR

2013-07-01

... each treatment process. (b) Control options: Group 1 wastewater streams for Table 9 compounds. The... section. (c) Control options: Group 1 wastewater streams for Table 8 compounds. The owner or operator...) Residuals. For each residual removed from a Group 1 wastewater stream, the owner or operator shall control...

40 CFR 63.138 - Process wastewater provisions-performance standards for treatment processes managing Group 1...

Code of Federal Regulations, 2011 CFR

2011-07-01

... each treatment process. (b) Control options: Group 1 wastewater streams for Table 9 compounds. The... section. (c) Control options: Group 1 wastewater streams for Table 8 compounds. The owner or operator...) Residuals. For each residual removed from a Group 1 wastewater stream, the owner or operator shall control...

Increased functional connectivity in the ventral and dorsal streams during retrieval of novel words in professional musicians.

PubMed

Dittinger, Eva; Valizadeh, Seyed Abolfazl; Jäncke, Lutz; Besson, Mireille; Elmer, Stefan

2018-02-01

Current models of speech and language processing postulate the involvement of two parallel processing streams (the dual stream model): a ventral stream involved in mapping sensory and phonological representations onto lexical and conceptual representations and a dorsal stream contributing to sound-to-motor mapping, articulation, and to how verbal information is encoded and manipulated in memory. Based on previous evidence showing that music training has an influence on language processing, cognitive functions, and word learning, we examined EEG-based intracranial functional connectivity in the ventral and dorsal streams while musicians and nonmusicians learned the meaning of novel words through picture-word associations. In accordance with the dual stream model, word learning was generally associated with increased beta functional connectivity in the ventral stream compared to the dorsal stream. In addition, in the linguistically most demanding "semantic task," musicians outperformed nonmusicians, and this behavioral advantage was accompanied by increased left-hemispheric theta connectivity in both streams. Moreover, theta coherence in the left dorsal pathway was positively correlated with the number of years of music training. These results provide evidence for a complex interplay within a network of brain regions involved in semantic processing and verbal memory functions, and suggest that intensive music training can modify its functional architecture leading to advantages in novel word learning. © 2017 Wiley Periodicals, Inc.

Complex Catchment Processes that Control Stream Nitrogen and Organic Matter Concentrations in a Northeastern USA Upland Catchment

NASA Astrophysics Data System (ADS)

Sebestyen, S. D.; Shanley, J. B.; Pellerin, B.; Saraceno, J.; Aiken, G. R.; Boyer, E. W.; Doctor, D. H.; Kendall, C.

2009-05-01

There is a need to understand the coupled biogeochemical and hydrological processes that control stream hydrochemistry in upland forested catchments. At watershed 9 (W-9) of the Sleepers River Research Watershed in the northeastern USA, we use high-frequency sampling, environmental tracers, end-member mixing analysis, and stream reach mass balances to understand dynamic factors affect forms and concentrations of nitrogen and organic matter in streamflow. We found that rates of stream nitrate processing changed during autumn baseflow and that up to 70% of nitrate inputs to a stream reach were retained. At the same time, the stream reach was a net source of the dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) fractions of dissolved organic matter (DOM). The in-stream nitrate loss and DOM gains are examples of hot moments of biogeochemical transformations during autumn when deciduous litter fall increases DOM availability. As hydrological flowpaths changed during rainfall events, the sources and transformations of nitrate and DOM differed from baseflow. For example, during storm flow we measured direct inputs of unprocessed atmospheric nitrate to streams that were as large as 30% of the stream nitrate loading. At the same time, stream DOM composition shifted to reflect inputs of reactive organic matter from surficial upland soils. The transport of atmospheric nitrate and reactive DOM to streams underscores the importance of quantifying source variation during short-duration stormflow events. Building upon these findings we present a conceptual model of interacting ecosystem processes that control the flow of water and nutrients to streams in a temperate upland catchment.

System for processing an encrypted instruction stream in hardware

DOE Office of Scientific and Technical Information (OSTI.GOV)

Griswold, Richard L.; Nickless, William K.; Conrad, Ryan C.

A system and method of processing an encrypted instruction stream in hardware is disclosed. Main memory stores the encrypted instruction stream and unencrypted data. A central processing unit (CPU) is operatively coupled to the main memory. A decryptor is operatively coupled to the main memory and located within the CPU. The decryptor decrypts the encrypted instruction stream upon receipt of an instruction fetch signal from a CPU core. Unencrypted data is passed through to the CPU core without decryption upon receipt of a data fetch signal.

Posterior Parietal Cortex Drives Inferotemporal Activations During Three-Dimensional Object Vision.

PubMed

Van Dromme, Ilse C; Premereur, Elsie; Verhoef, Bram-Ernst; Vanduffel, Wim; Janssen, Peter

2016-04-01

The primate visual system consists of a ventral stream, specialized for object recognition, and a dorsal visual stream, which is crucial for spatial vision and actions. However, little is known about the interactions and information flow between these two streams. We investigated these interactions within the network processing three-dimensional (3D) object information, comprising both the dorsal and ventral stream. Reversible inactivation of the macaque caudal intraparietal area (CIP) during functional magnetic resonance imaging (fMRI) reduced fMRI activations in posterior parietal cortex in the dorsal stream and, surprisingly, also in the inferotemporal cortex (ITC) in the ventral visual stream. Moreover, CIP inactivation caused a perceptual deficit in a depth-structure categorization task. CIP-microstimulation during fMRI further suggests that CIP projects via posterior parietal areas to the ITC in the ventral stream. To our knowledge, these results provide the first causal evidence for the flow of visual 3D information from the dorsal stream to the ventral stream, and identify CIP as a key area for depth-structure processing. Thus, combining reversible inactivation and electrical microstimulation during fMRI provides a detailed view of the functional interactions between the two visual processing streams.

Posterior Parietal Cortex Drives Inferotemporal Activations During Three-Dimensional Object Vision

PubMed Central

Van Dromme, Ilse C.; Premereur, Elsie; Verhoef, Bram-Ernst; Vanduffel, Wim; Janssen, Peter

2016-01-01

The primate visual system consists of a ventral stream, specialized for object recognition, and a dorsal visual stream, which is crucial for spatial vision and actions. However, little is known about the interactions and information flow between these two streams. We investigated these interactions within the network processing three-dimensional (3D) object information, comprising both the dorsal and ventral stream. Reversible inactivation of the macaque caudal intraparietal area (CIP) during functional magnetic resonance imaging (fMRI) reduced fMRI activations in posterior parietal cortex in the dorsal stream and, surprisingly, also in the inferotemporal cortex (ITC) in the ventral visual stream. Moreover, CIP inactivation caused a perceptual deficit in a depth-structure categorization task. CIP-microstimulation during fMRI further suggests that CIP projects via posterior parietal areas to the ITC in the ventral stream. To our knowledge, these results provide the first causal evidence for the flow of visual 3D information from the dorsal stream to the ventral stream, and identify CIP as a key area for depth-structure processing. Thus, combining reversible inactivation and electrical microstimulation during fMRI provides a detailed view of the functional interactions between the two visual processing streams. PMID:27082854

Comparison of drinking water treatment process streams for optimal bacteriological water quality.

PubMed

Ho, Lionel; Braun, Kalan; Fabris, Rolando; Hoefel, Daniel; Morran, Jim; Monis, Paul; Drikas, Mary

2012-08-01

Four pilot-scale treatment process streams (Stream 1 - Conventional treatment (coagulation/flocculation/dual media filtration); Stream 2 - Magnetic ion exchange (MIEX)/Conventional treatment; Stream 3 - MIEX/Conventional treatment/granular activated carbon (GAC) filtration; Stream 4 - Microfiltration/nanofiltration) were commissioned to compare their effectiveness in producing high quality potable water prior to disinfection. Despite receiving highly variable source water quality throughout the investigation, each stream consistently reduced colour and turbidity to below Australian Drinking Water Guideline levels, with the exception of Stream 1 which was difficult to manage due to the reactive nature of coagulation control. Of particular interest was the bacteriological quality of the treated waters where flow cytometry was shown to be the superior monitoring tool in comparison to the traditional heterotrophic plate count method. Based on removal of total and active bacteria, the treatment process streams were ranked in the order: Stream 4 (average log removal of 2.7) > Stream 2 (average log removal of 2.3) > Stream 3 (average log removal of 1.5) > Stream 1 (average log removal of 1.0). The lower removals in Stream 3 were attributed to bacteria detaching from the GAC filter. Bacterial community analysis revealed that the treatments affected the bacteria present, with the communities in streams incorporating conventional treatment clustering with each other, while the community composition of Stream 4 was very different to those of Streams 1, 2 and 3. MIEX treatment was shown to enhance removal of bacteria due to more efficient flocculation which was validated through the novel application of the photometric dispersion analyser. Copyright © 2012 Elsevier Ltd. All rights reserved.

Development of the Hydroecological Integrity Assessment Process for Determining Environmental Flows for New Jersey Streams

USGS Publications Warehouse

Kennen, Jonathan G.; Henriksen, James A.; Nieswand, Steven P.

2007-01-01

The natural flow regime paradigm and parallel stream ecological concepts and theories have established the benefits of maintaining or restoring the full range of natural hydrologic variation for physiochemical processes, biodiversity, and the evolutionary potential of aquatic and riparian communities. A synthesis of recent advances in hydroecological research coupled with stream classification has resulted in a new process to determine environmental flows and assess hydrologic alteration. This process has national and international applicability. It allows classification of streams into hydrologic stream classes and identification of a set of non-redundant and ecologically relevant hydrologic indices for 10 critical sub-components of flow. Three computer programs have been developed for implementing the Hydroecological Integrity Assessment Process (HIP): (1) the Hydrologic Indices Tool (HIT), which calculates 171 ecologically relevant hydrologic indices on the basis of daily-flow and peak-flow stream-gage data; (2) the New Jersey Hydrologic Assessment Tool (NJHAT), which can be used to establish a hydrologic baseline period, provide options for setting baseline environmental-flow standards, and compare past and proposed streamflow alterations; and (3) the New Jersey Stream Classification Tool (NJSCT), designed for placing unclassified streams into pre-defined stream classes. Biological and multivariate response models including principal-component, cluster, and discriminant-function analyses aided in the development of software and implementation of the HIP for New Jersey. A pilot effort is currently underway by the New Jersey Department of Environmental Protection in which the HIP is being used to evaluate the effects of past and proposed surface-water use, ground-water extraction, and land-use changes on stream ecosystems while determining the most effective way to integrate the process into ongoing regulatory programs. Ultimately, this scientifically defensible process will help to quantify the effects of anthropogenic changes and development on hydrologic variability and help planners and resource managers balance current and future water requirements with ecological needs.

Machine vision system for automated detection of stained pistachio nuts

NASA Astrophysics Data System (ADS)

Pearson, Tom C.

1995-01-01

A machine vision system was developed to separate stained pistachio nuts, which comprise of about 5% of the California crop, from unstained nuts. The system may be used to reduce labor involved with manual grading or to remove aflatoxin contaminated product from low grade process streams. The system was tested on two different pistachio process streams: the bi- chromatic color sorter reject stream and the small nut shelling stock stream. The system had a minimum overall error rate of 14% for the bi-chromatic sorter reject stream and 15% for the small shelling stock stream.

Ammonia Monitor

NASA Technical Reports Server (NTRS)

Sauer, Richard L. (Inventor); Akse, James R. (Inventor); Thompson, John O. (Inventor); Atwater, James E. (Inventor)

1999-01-01

Ammonia monitor and method of use are disclosed. A continuous, real-time determination of the concentration of ammonia in an aqueous process stream is possible over a wide dynamic range of concentrations. No reagents are required because pH is controlled by an in-line solid-phase base. Ammonia is selectively transported across a membrane from the process stream to an analytical stream to an analytical stream under pH control. The specific electrical conductance of the analytical stream is measured and used to determine the concentration of ammonia.

Mass, energy and material balances of SRF production process. Part 2: SRF produced from construction and demolition waste.

PubMed

Nasrullah, Muhammad; Vainikka, Pasi; Hannula, Janne; Hurme, Markku; Kärki, Janne

2014-11-01

In this work, the fraction of construction and demolition waste (C&D waste) complicated and economically not feasible to sort out for recycling purposes is used to produce solid recovered fuel (SRF) through mechanical treatment (MT). The paper presents the mass, energy and material balances of this SRF production process. All the process streams (input and output) produced in MT waste sorting plant to produce SRF from C&D waste are sampled and treated according to CEN standard methods for SRF. Proximate and ultimate analysis of these streams is performed and their composition is determined. Based on this analysis and composition of process streams their mass, energy and material balances are established for SRF production process. By mass balance means the overall mass flow of input waste material stream in the various output streams and material balances mean the mass flow of components of input waste material stream (such as paper and cardboard, wood, plastic (soft), plastic (hard), textile and rubber) in the various output streams of SRF production process. The results from mass balance of SRF production process showed that of the total input C&D waste material to MT waste sorting plant, 44% was recovered in the form of SRF, 5% as ferrous metal, 1% as non-ferrous metal, and 28% was sorted out as fine fraction, 18% as reject material and 4% as heavy fraction. The energy balance of this SRF production process showed that of the total input energy content of C&D waste material to MT waste sorting plant, 74% was recovered in the form of SRF, 16% belonged to the reject material and rest 10% belonged to the streams of fine fraction and heavy fraction. From the material balances of this process, mass fractions of plastic (soft), paper and cardboard, wood and plastic (hard) recovered in the SRF stream were 84%, 82%, 72% and 68% respectively of their input masses to MT plant. A high mass fraction of plastic (PVC) and rubber material was found in the reject material stream. Streams of heavy fraction and fine fraction mainly contained non-combustible material (such as stone/rock, sand particles and gypsum material). Copyright © 2014 Elsevier Ltd. All rights reserved.

On the organization of the perisylvian cortex: Insights from the electrophysiology of language. Comment on "Towards a Computational Comparative Neuroprimatology: Framing the language-ready brain" by M.A. Arbib

NASA Astrophysics Data System (ADS)

Brouwer, Harm; Crocker, Matthew W.

2016-03-01

The Mirror System Hypothesis (MSH) on the evolution of the language-ready brain draws upon the parallel dorsal-ventral stream architecture for vision [1]. The dorsal ;how; stream provides a mapping of parietally-mediated affordances onto the motor system (supporting preshape), whereas the ventral ;what; stream engages in object recognition and visual scene analysis (supporting pantomime and verbal description). Arbib attempts to integrate this MSH perspective with a recent conceptual dorsal-ventral stream model of auditory language comprehension [5] (henceforth, the B&S model). In the B&S model, the dorsal stream engages in time-dependent combinatorial processing, which subserves syntactic structuring and linkage to action, whereas the ventral stream performs time-independent unification of conceptual schemata. These streams are integrated in the left Inferior Frontal Gyrus (lIFG), which is assumed to subserve cognitive control, and no linguistic processing functions. Arbib criticizes the B&S model on two grounds: (i) the time-independence of the semantic processing in the ventral stream (by arguing that semantic processing is just as time-dependent as syntactic processing), and (ii) the absence of linguistic processing in the lIFG (reconciling syntactic and semantic representations is very much linguistic processing proper). Here, we provide further support for these two points of criticism on the basis of insights from the electrophysiology of language. In the course of our argument, we also sketch the contours of an alternative model that may prove better suited for integration with the MSH.

Efficient gas-separation process to upgrade dilute methane stream for use as fuel

DOEpatents

Wijmans, Johannes G [Menlo Park, CA; Merkel, Timothy C [Menlo Park, CA; Lin, Haiqing [Mountain View, CA; Thompson, Scott [Brecksville, OH; Daniels, Ramin [San Jose, CA

2012-03-06

A membrane-based gas separation process for treating gas streams that contain methane in low concentrations. The invention involves flowing the stream to be treated across the feed side of a membrane and flowing a sweep gas stream, usually air, across the permeate side. Carbon dioxide permeates the membrane preferentially and is picked up in the sweep air stream on the permeate side; oxygen permeates in the other direction and is picked up in the methane-containing stream. The resulting residue stream is enriched in methane as well as oxygen and has an EMC value enabling it to be either flared or combusted by mixing with ordinary air.

Platinum recovery from industrial process streams by halophilic bacteria: Influence of salt species and platinum speciation.

PubMed

Maes, Synthia; Claus, Mathias; Verbeken, Kim; Wallaert, Elien; De Smet, Rebecca; Vanhaecke, Frank; Boon, Nico; Hennebel, Tom

2016-11-15

The increased use and criticality of platinum asks for the development of effective low-cost strategies for metal recovery from process and waste streams. Although biotechnological processes can be applied for the valorization of diluted aqueous industrial streams, investigations considering real stream conditions (e.g., high salt levels, acidic pH, metal speciation) are lacking. This study investigated the recovery of platinum by a halophilic microbial community in the presence of increased salt concentrations (10-80 g L -1 ), different salt matrices (phosphate salts, sea salts and NH 4 Cl) and a refinery process stream. The halophiles were able to recover 79-99% of the Pt at 10-80 g L -1 salts and at pH 2.3. Transmission electron microscopy suggested a positive correlation between intracellular Pt cluster size and elevated salt concentrations. Furthermore, the halophiles recovered 46-95% of the Pt-amine complex Pt[NH 3 ] 4 2+ from a process stream after the addition of an alternative Pt source (K 2 PtCl 4 , 0.1-1.0 g L -1 Pt). Repeated Pt-tetraamine recovery (from an industrial process stream) was obtained after concomitant addition of fresh biomass and harvesting of Pt saturated biomass. This study demonstrates how aqueous Pt streams can be transformed into Pt rich biomass, which would be an interesting feed of a precious metals refinery. Copyright © 2016 Elsevier Ltd. All rights reserved.

Two stroke engine exhaust emissions separator

DOEpatents

Turner, Terry D.; Wilding, Bruce M.; McKellar, Michael G.; Raterman, Kevin T.

2003-04-22

A separator for substantially resolving at least one component of a process stream, such as from the exhaust of an internal combustion engine. The separator includes a body defining a chamber therein. A nozzle housing is located proximate the chamber. An exhaust inlet is in communication with the nozzle housing and the chamber. A nozzle assembly is positioned in the nozzle housing and includes a nozzle moveable within and relative to the nozzle housing. The nozzle includes at least one passage formed therethrough such that a process stream entering the exhaust inlet connection passes through the passage formed in the nozzle and imparts a substantially rotational flow to the process stream as it enters the chamber. A positioning member is configured to position the nozzle relative to the nozzle housing in response to changes in process stream pressure thereby adjusting flowrate of said process stream entering into the chamber.

Two stroke engine exhaust emissions separator

DOEpatents

Turner, Terry D.; Wilding, Bruce M.; McKellar, Michael G.; Raterman, Kevin T.

2002-01-01

A separator for substantially resolving at least one component of a process stream, such as from the exhaust of an internal combustion engine. The separator includes a body defining a chamber therein. A nozzle housing is located proximate the chamber. An exhaust inlet is in communication with the nozzle housing and the chamber. A nozzle assembly is positioned in the nozzle housing and includes a nozzle moveable within and relative to the nozzle housing. The nozzle includes at least one passage formed therethrough such that a process stream entering the exhaust inlet connection passes through the passage formed in the nozzle, which imparts a substantially rotational flow to the process stream as it enters the chamber. A positioning member is configured to position the nozzle relative to the nozzle housing in response to changes in process stream pressure to adjust flowrate of said process stream entering into the chamber.

DWPF RECYCLE EVAPORATOR FLOWSHEET EVALUATION (U)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stone, M

2005-04-30

The Defense Waste Processing Facility (DWPF) converts the high level waste slurries stored at the Savannah River Site into borosilicate glass for long-term storage. The vitrification process results in the generation of approximately five gallons of dilute recycle streams for each gallon of waste slurry vitrified. This dilute recycle stream is currently transferred to the H-area Tank Farm and amounts to approximately 1,400,000 gallons of effluent per year. Process changes to incorporate salt waste could increase the amount of effluent to approximately 2,900,000 gallons per year. The recycle consists of two major streams and four smaller streams. The first majormore » recycle stream is condensate from the Chemical Process Cell (CPC), and is collected in the Slurry Mix Evaporator Condensate Tank (SMECT). The second major recycle stream is the melter offgas which is collected in the Off Gas Condensate Tank (OGCT). The four smaller streams are the sample flushes, sump flushes, decon solution, and High Efficiency Mist Eliminator (HEME) dissolution solution. These streams are collected in the Decontamination Waste Treatment Tank (DWTT) or the Recycle Collection Tank (RCT). All recycle streams are currently combined in the RCT and treated with sodium nitrite and sodium hydroxide prior to transfer to the tank farm. Tank Farm space limitations and previous outages in the 2H Evaporator system due to deposition of sodium alumino-silicates have led to evaluation of alternative methods of dealing with the DWPF recycle. One option identified for processing the recycle was a dedicated evaporator to concentrate the recycle stream to allow the solids to be recycled to the DWPF Sludge Receipt and Adjustment Tank (SRAT) and the condensate from this evaporation process to be sent and treated in the Effluent Treatment Plant (ETP). In order to meet process objectives, the recycle stream must be concentrated to 1/30th of the feed volume during the evaporation process. The concentrated stream must be pumpable to the DWPF SRAT vessel and should not precipitate solids to avoid fouling the evaporator vessel and heat transfer coils. The evaporation process must not generate excessive foam and must have a high Decontamination Factor (DF) for many species in the evaporator feed to allow the condensate to be transferred to the ETP. An initial scoping study was completed in 2001 to evaluate the feasibility of the evaporator which concluded that the concentration objectives could be met. This initial study was based on initial estimates of recycle concentration and was based solely on OLI modeling of the evaporation process. The Savannah River National Laboratory (SRNL) has completed additional studies using simulated recycle streams and OLI{reg_sign} simulations. Based on this work, the proposed flowsheet for the recycle evaporator was evaluated for feasibility, evaporator design considerations, and impact on the DWPF process. This work was in accordance with guidance from DWPF-E and was performed in accordance with the Technical Task and Quality Assurance Plan.« less

High rates of organic carbon processing in the hyporheic zone of intermittent streams.

PubMed

Burrows, Ryan M; Rutlidge, Helen; Bond, Nick R; Eberhard, Stefan M; Auhl, Alexandra; Andersen, Martin S; Valdez, Dominic G; Kennard, Mark J

2017-10-16

Organic carbon cycling is a fundamental process that underpins energy transfer through the biosphere. However, little is known about the rates of particulate organic carbon processing in the hyporheic zone of intermittent streams, which is often the only wetted environment remaining when surface flows cease. We used leaf litter and cotton decomposition assays, as well as rates of microbial respiration, to quantify rates of organic carbon processing in surface and hyporheic environments of intermittent and perennial streams under a range of substrate saturation conditions. Leaf litter processing was 48% greater, and cotton processing 124% greater, in the hyporheic zone compared to surface environments when calculated over multiple substrate saturation conditions. Processing was also greater in more saturated surface environments (i.e. pools). Further, rates of microbial respiration on incubated substrates in the hyporheic zone were similar to, or greater than, rates in surface environments. Our results highlight that intermittent streams are important locations for particulate organic carbon processing and that the hyporheic zone sustains this fundamental process even without surface flow. Not accounting for carbon processing in the hyporheic zone of intermittent streams may lead to an underestimation of its local ecological significance and collective contribution to landscape carbon processes.

Where’s Waldo? How perceptual, cognitive, and emotional brain processes cooperate during learning to categorize and find desired objects in a cluttered scene

PubMed Central

Chang, Hung-Cheng; Grossberg, Stephen; Cao, Yongqiang

2014-01-01

The Where’s Waldo problem concerns how individuals can rapidly learn to search a scene to detect, attend, recognize, and look at a valued target object in it. This article develops the ARTSCAN Search neural model to clarify how brain mechanisms across the What and Where cortical streams are coordinated to solve the Where’s Waldo problem. The What stream learns positionally-invariant object representations, whereas the Where stream controls positionally-selective spatial and action representations. The model overcomes deficiencies of these computationally complementary properties through What and Where stream interactions. Where stream processes of spatial attention and predictive eye movement control modulate What stream processes whereby multiple view- and positionally-specific object categories are learned and associatively linked to view- and positionally-invariant object categories through bottom-up and attentive top-down interactions. Gain fields control the coordinate transformations that enable spatial attention and predictive eye movements to carry out this role. What stream cognitive-emotional learning processes enable the focusing of motivated attention upon the invariant object categories of desired objects. What stream cognitive names or motivational drives can prime a view- and positionally-invariant object category of a desired target object. A volitional signal can convert these primes into top-down activations that can, in turn, prime What stream view- and positionally-specific categories. When it also receives bottom-up activation from a target, such a positionally-specific category can cause an attentional shift in the Where stream to the positional representation of the target, and an eye movement can then be elicited to foveate it. These processes describe interactions among brain regions that include visual cortex, parietal cortex, inferotemporal cortex, prefrontal cortex (PFC), amygdala, basal ganglia (BG), and superior colliculus (SC). PMID:24987339

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yan, Rui; Praggastis, Brenda L.; Smith, William P.

While streaming data have become increasingly more popular in business and research communities, semantic models and processing software for streaming data have not kept pace. Traditional semantic solutions have not addressed transient data streams. Semantic web languages (e.g., RDF, OWL) have typically addressed static data settings and linked data approaches have predominantly addressed static or growing data repositories. Streaming data settings have some fundamental differences; in particular, data are consumed on the fly and data may expire. Stream reasoning, a combination of stream processing and semantic reasoning, has emerged with the vision of providing "smart" processing of streaming data. C-SPARQLmore » is a prominent stream reasoning system that handles semantic (RDF) data streams. Many stream reasoning systems including C-SPARQL use a sliding window and use data arrival time to evict data. For data streams that include expiration times, a simple arrival time scheme is inadequate if the window size does not match the expiration period. In this paper, we propose a cache-enabled, order-aware, ontology-based stream reasoning framework. This framework consumes RDF streams with expiration timestamps assigned by the streaming source. Our framework utilizes both arrival and expiration timestamps in its cache eviction policies. In addition, we introduce the notion of "semantic importance" which aims to address the relevance of data to the expected reasoning, thus enabling the eviction algorithms to be more context- and reasoning-aware when choosing what data to maintain for question answering. We evaluate this framework by implementing three different prototypes and utilizing five metrics. The trade-offs of deploying the proposed framework are also discussed.« less

Geospatial Data Stream Processing in Python Using FOSS4G Components

NASA Astrophysics Data System (ADS)

McFerren, G.; van Zyl, T.

2016-06-01

One viewpoint of current and future IT systems holds that there is an increase in the scale and velocity at which data are acquired and analysed from heterogeneous, dynamic sources. In the earth observation and geoinformatics domains, this process is driven by the increase in number and types of devices that report location and the proliferation of assorted sensors, from satellite constellations to oceanic buoy arrays. Much of these data will be encountered as self-contained messages on data streams - continuous, infinite flows of data. Spatial analytics over data streams concerns the search for spatial and spatio-temporal relationships within and amongst data "on the move". In spatial databases, queries can assess a store of data to unpack spatial relationships; this is not the case on streams, where spatial relationships need to be established with the incomplete data available. Methods for spatially-based indexing, filtering, joining and transforming of streaming data need to be established and implemented in software components. This article describes the usage patterns and performance metrics of a number of well known FOSS4G Python software libraries within the data stream processing paradigm. In particular, we consider the RTree library for spatial indexing, the Shapely library for geometric processing and transformation and the PyProj library for projection and geodesic calculations over streams of geospatial data. We introduce a message oriented Python-based geospatial data streaming framework called Swordfish, which provides data stream processing primitives, functions, transports and a common data model for describing messages, based on the Open Geospatial Consortium Observations and Measurements (O&M) and Unidata Common Data Model (CDM) standards. We illustrate how the geospatial software components are integrated with the Swordfish framework. Furthermore, we describe the tight temporal constraints under which geospatial functionality can be invoked when processing high velocity, potentially infinite geospatial data streams. The article discusses the performance of these libraries under simulated streaming loads (size, complexity and volume of messages) and how they can be deployed and utilised with Swordfish under real load scenarios, illustrated by a set of Vessel Automatic Identification System (AIS) use cases. We conclude that the described software libraries are able to perform adequately under geospatial data stream processing scenarios - many real application use cases will be handled sufficiently by the software.

The Role of Riparian Vegetation in Protecting and Improving Chemical Water Quality in Streams

Treesearch

Michael G. Dosskey; Philippe Vidon; Noel P. Gurwick; Craig J. Allan; Tim P. Duval; Richard Lowrance

2010-01-01

We review the research literature and summarize the major processes by which riparian vegetation influences chemical water quality in streams, as well as how these processes vary among vegetation types, and discuss how these processes respond to removal and restoration of riparian vegetation and thereby determine the timing and level of response in stream water quality...

New metrics for evaluating channel networks extracted in grid digital elevation models

NASA Astrophysics Data System (ADS)

Orlandini, S.; Moretti, G.

2017-12-01

Channel networks are critical components of drainage basins and delta regions. Despite the important role played by these systems in hydrology and geomorphology, there are at present no well-defined methods to evaluate numerically how two complex channel networks are geometrically far apart. The present study introduces new metrics for evaluating numerically channel networks extracted in grid digital elevation models with respect to a reference channel network (see the figure below). Streams of the evaluated network (EN) are delineated as in the Horton ordering system and examined through a priority climbing algorithm based on the triple index (ID1,ID2,ID3), where ID1 is a stream identifier that increases as the elevation of lower end of the stream increases, ID2 indicates the ID1 of the draining stream, and ID3 is the ID1 of the corresponding stream in the reference network (RN). Streams of the RN are identified by the double index (ID1,ID2). Streams of the EN are processed in the order of increasing ID1 (plots a-l in the figure below). For each processed stream of the EN, the closest stream of the RN is sought by considering all the streams of the RN sharing the same ID2. This ID2 in the RN is equal in the EN to the ID3 of the stream draining the processed stream, the one having ID1 equal to the ID2 of the processed stream. The mean stream planar distance (MSPD) and the mean stream elevation drop (MSED) are computed as the mean distance and drop, respectively, between corresponding streams. The MSPD is shown to be useful for evaluating slope direction methods and thresholds for channel initiation, whereas the MSED is shown to indicate the ability of grid coarsening strategies to retain the profiles of observed channels. The developed metrics fill a gap in the existing literature by allowing hydrologists and geomorphologists to compare descriptions of a fixed physical system obtained by using different terrain analysis methods, or different physical systems described by using the same methods.

VPipe: Virtual Pipelining for Scheduling of DAG Stream Query Plans

NASA Astrophysics Data System (ADS)

Wang, Song; Gupta, Chetan; Mehta, Abhay

There are data streams all around us that can be harnessed for tremendous business and personal advantage. For an enterprise-level stream processing system such as CHAOS [1] (Continuous, Heterogeneous Analytic Over Streams), handling of complex query plans with resource constraints is challenging. While several scheduling strategies exist for stream processing, efficient scheduling of complex DAG query plans is still largely unsolved. In this paper, we propose a novel execution scheme for scheduling complex directed acyclic graph (DAG) query plans with meta-data enriched stream tuples. Our solution, called Virtual Pipelined Chain (or VPipe Chain for short), effectively extends the "Chain" pipelining scheduling approach to complex DAG query plans.

Investigating category- and shape-selective neural processing in ventral and dorsal visual stream under interocular suppression.

PubMed

Ludwig, Karin; Kathmann, Norbert; Sterzer, Philipp; Hesselmann, Guido

2015-01-01

Recent behavioral and neuroimaging studies using continuous flash suppression (CFS) have suggested that action-related processing in the dorsal visual stream might be independent of perceptual awareness, in line with the "vision-for-perception" versus "vision-for-action" distinction of the influential dual-stream theory. It remains controversial if evidence suggesting exclusive dorsal stream processing of tool stimuli under CFS can be explained by their elongated shape alone or by action-relevant category representations in dorsal visual cortex. To approach this question, we investigated category- and shape-selective functional magnetic resonance imaging-blood-oxygen level-dependent responses in both visual streams using images of faces and tools. Multivariate pattern analysis showed enhanced decoding of elongated relative to non-elongated tools, both in the ventral and dorsal visual stream. The second aim of our study was to investigate whether the depth of interocular suppression might differentially affect processing in dorsal and ventral areas. However, parametric modulation of suppression depth by varying the CFS mask contrast did not yield any evidence for differential modulation of category-selective activity. Together, our data provide evidence for shape-selective processing under CFS in both dorsal and ventral stream areas and, therefore, do not support the notion that dorsal "vision-for-action" processing is exclusively preserved under interocular suppression. © 2014 Wiley Periodicals, Inc.

Foundations for Streaming Model Transformations by Complex Event Processing.

PubMed

Dávid, István; Ráth, István; Varró, Dániel

2018-01-01

Streaming model transformations represent a novel class of transformations to manipulate models whose elements are continuously produced or modified in high volume and with rapid rate of change. Executing streaming transformations requires efficient techniques to recognize activated transformation rules over a live model and a potentially infinite stream of events. In this paper, we propose foundations of streaming model transformations by innovatively integrating incremental model query, complex event processing (CEP) and reactive (event-driven) transformation techniques. Complex event processing allows to identify relevant patterns and sequences of events over an event stream. Our approach enables event streams to include model change events which are automatically and continuously populated by incremental model queries. Furthermore, a reactive rule engine carries out transformations on identified complex event patterns. We provide an integrated domain-specific language with precise semantics for capturing complex event patterns and streaming transformations together with an execution engine, all of which is now part of the Viatra reactive transformation framework. We demonstrate the feasibility of our approach with two case studies: one in an advanced model engineering workflow; and one in the context of on-the-fly gesture recognition.

A Stream Morphology Classification for Eco-hydraulic Purposes Based on Geospatial Data: a Solute Transport Application Case

NASA Astrophysics Data System (ADS)

Jiménez Jaramillo, M. A.; Camacho Botero, L. A.; Vélez Upegui, J. I.

2010-12-01

Variation in stream morphology along a basin drainage network leads to different hydraulic patterns and sediment transport processes. Moreover, solute transport processes along streams, and stream habitats for fisheries and microorganisms, rely on stream corridor structure, including elements such as bed forms, channel patterns, riparian vegetation, and the floodplain. In this work solute transport processes simulation and stream habitat identification are carried out at the basin scale. A reach-scale morphological classification system based on channel slope and specific stream power was implemented by using digital elevation models and hydraulic geometry relationships. Although the morphological framework allows identification of cascade, step-pool, plane bed and pool-riffle morphologies along the drainage network, it still does not account for floodplain configuration and bed-forms identification of those channel types. Hence, as a first application case in order to obtain parsimonious three-dimensional characterizations of drainage channels, the morphological framework has been updated by including topographical floodplain delimitation through a Multi-resolution Valley Bottom Flatness Index assessing, and a stochastic bed form representation of the step-pool morphology. Model outcomes were tested in relation to in-stream water storage for different flow conditions and representative travel times according to the Aggregated Dead Zone -ADZ- model conceptualization of solute transport processes.

Sewage treatment method

DOEpatents

Fassbender, Alex G.

1995-01-01

The invention greatly reduces the amount of ammonia in sewage plant effluent. The process of the invention has three main steps. The first step is dewatering without first digesting, thereby producing a first ammonia-containing stream having a low concentration of ammonia, and a second solids-containing stream. The second step is sending the second solids-containing stream through a means for separating the solids from the liquid and producing an aqueous stream containing a high concentration of ammonia. The third step is removal of ammonia from the aqueous stream using a hydrothermal process.

Macrophyte presence is an indicator of enhanced denitrification and nitrification in sediments of a temperate restored agricultural stream

EPA Science Inventory

Stream macrophytes are often removed with their sediments to deepen stream channels, stabilize channel banks, or provide habitat for target species. These sediments may support enhanced nitrogen processing. To evaluate sediment nitrogen processing, identify seasonal patterns, and...

Serial and Parallel Processing in the Primate Auditory Cortex Revisited

PubMed Central

Recanzone, Gregg H.; Cohen, Yale E.

2009-01-01

Over a decade ago it was proposed that the primate auditory cortex is organized in a serial and parallel manner in which there is a dorsal stream processing spatial information and a ventral stream processing non-spatial information. This organization is similar to the “what”/“where” processing of the primate visual cortex. This review will examine several key studies, primarily electrophysiological, that have tested this hypothesis. We also review several human imaging studies that have attempted to define these processing streams in the human auditory cortex. While there is good evidence that spatial information is processed along a particular series of cortical areas, the support for a non-spatial processing stream is not as strong. Why this should be the case and how to better test this hypothesis is also discussed. PMID:19686779

EFFECTS OF HYDROLOGY ON NITROGEN PROCESSING IN A RESTORED URBAN STREAM

EPA Science Inventory

In 2001, EPA undertook an intensive research effort to evaluate the impact of stream restoration on water quality at a degraded stream in an urban watershed. An essential piece of this comprehensive study was to characterize, measure and quantify stream ground water/ stream wate...

Experimental reductions in stream flow alter litter processing and consumer subsidies in headwater streams

Treesearch

Robert M. Northington; Jackson R. Webster

2017-01-01

SummaryForested headwater streams are connected to their surrounding catchments by a reliance on terrestrial subsidies. Changes in precipitation patterns and stream flow represent a potential disruption in stream ecosystem function, as the delivery of terrestrial detritus to aquatic consumers and...

40 CFR 63.146 - Process wastewater provisions-reporting.

Code of Federal Regulations, 2014 CFR

2014-07-01

... wastewater provisions—reporting. (a) For each waste management unit, treatment process, or control device... for Group 2 wastewater streams. This paragraph does not apply to Group 2 wastewater streams that are used to comply with § 63.138(g). For Group 2 wastewater streams, the owner or operator shall include...

40 CFR 63.146 - Process wastewater provisions-reporting.

Code of Federal Regulations, 2012 CFR

2012-07-01

... wastewater provisions—reporting. (a) For each waste management unit, treatment process, or control device... for Group 2 wastewater streams. This paragraph does not apply to Group 2 wastewater streams that are used to comply with § 63.138(g). For Group 2 wastewater streams, the owner or operator shall include...

40 CFR 63.146 - Process wastewater provisions-reporting.

Code of Federal Regulations, 2011 CFR

2011-07-01

... wastewater provisions—reporting. (a) For each waste management unit, treatment process, or control device... for Group 2 wastewater streams. This paragraph does not apply to Group 2 wastewater streams that are used to comply with § 63.138(g). For Group 2 wastewater streams, the owner or operator shall include...

40 CFR 63.146 - Process wastewater provisions-reporting.

Code of Federal Regulations, 2013 CFR

2013-07-01

... wastewater provisions—reporting. (a) For each waste management unit, treatment process, or control device... for Group 2 wastewater streams. This paragraph does not apply to Group 2 wastewater streams that are used to comply with § 63.138(g). For Group 2 wastewater streams, the owner or operator shall include...

Continuous-flow free acid monitoring method and system

DOEpatents

Strain, J.E.; Ross, H.H.

1980-01-11

A free acid monitoring method and apparatus is provided for continuously measuring the excess acid present in a process stream. The disclosed monitoring system and method is based on the relationship of the partial pressure ratio of water and acid in equilibrium with an acid solution at constant temperature. A portion of the process stream is pumped into and flows through the monitor under the influence of gravity and back to the process stream. A continuous flowing sample is vaporized at a constant temperature and the vapor is subsequently condensed. Conductivity measurements of the condensate produces a nonlinear response function from which the free acid molarity of the sample process stream is determined.

Continuous-flow free acid monitoring method and system

DOEpatents

Strain, James E.; Ross, Harley H.

1981-01-01

A free acid monitoring method and apparatus is provided for continuously measuring the excess acid present in a process stream. The disclosed monitoring system and method is based on the relationship of the partial pressure ratio of water and acid in equilibrium with an acid solution at constant temperature. A portion of the process stream is pumped into and flows through the monitor under the influence of gravity and back to the process stream. A continuous flowing sample is vaporized at a constant temperature and the vapor is subsequently condensed. Conductivity measurements of the condensate produces a nonlinear response function from which the free acid molarity of the sample process stream is determined.

Controlled temperature expansion in oxygen production by molten alkali metal salts

DOEpatents

Erickson, Donald C.

1985-06-04

A continuous process is set forth for the production of oxygen from an oxygen containing gas stream, such as air, by contacting a feed gas stream with a molten solution of an oxygen acceptor to oxidize the acceptor and cyclically regenerating the oxidized acceptor by releasing oxygen from the acceptor wherein the oxygen-depleted gas stream from the contact zone is treated sequentially to temperature reduction by heat exchange against the feed stream so as to condense out entrained oxygen acceptor for recycle to the process, combustion of the gas stream with fuel to elevate its temperature and expansion of the combusted high temperature gas stream in a turbine to recover power.

Controlled temperature expansion in oxygen production by molten alkali metal salts

DOEpatents

Erickson, D.C.

1985-06-04

A continuous process is set forth for the production of oxygen from an oxygen containing gas stream, such as air, by contacting a feed gas stream with a molten solution of an oxygen acceptor to oxidize the acceptor and cyclically regenerating the oxidized acceptor by releasing oxygen from the acceptor wherein the oxygen-depleted gas stream from the contact zone is treated sequentially to temperature reduction by heat exchange against the feed stream so as to condense out entrained oxygen acceptor for recycle to the process, combustion of the gas stream with fuel to elevate its temperature and expansion of the combusted high temperature gas stream in a turbine to recover power. 1 fig.

Methanation of gas streams containing carbon monoxide and hydrogen

DOEpatents

Frost, Albert C.

1983-01-01

Carbon monoxide-containing gas streams having a relatively high concentration of hydrogen are pretreated so as to remove the hydrogen in a recoverable form for use in the second step of a cyclic, essentially two-step process for the production of methane. The thus-treated streams are then passed over a catalyst to deposit a surface layer of active surface carbon thereon essentially without the formation of inactive coke. This active carbon is reacted with said hydrogen removed from the feed gas stream to form methane. The utilization of the CO in the feed gas stream is appreciably increased, enhancing the overall process for the production of relatively pure, low-cost methane from CO-containing waste gas streams.

Method for removing undesired particles from gas streams

DOEpatents

Durham, M.D.; Schlager, R.J.; Ebner, T.G.; Stewart, R.M.; Hyatt, D.E.; Bustard, C.J.; Sjostrom, S.

1998-11-10

The present invention discloses a process for removing undesired particles from a gas stream including the steps of contacting a composition containing an adhesive with the gas stream; collecting the undesired particles and adhesive on a collection surface to form an aggregate comprising the adhesive and undesired particles on the collection surface; and removing the agglomerate from the collection zone. The composition may then be atomized and injected into the gas stream. The composition may include a liquid that vaporizes in the gas stream. After the liquid vaporizes, adhesive particles are entrained in the gas stream. The process may be applied to electrostatic precipitators and filtration systems to improve undesired particle collection efficiency. 11 figs.

Method and apparatus for decreased undesired particle emissions in gas streams

DOEpatents

Durham, M.D.; Schlager, R.J.; Ebner, T.G.; Stewart, R.M.; Bustard, C.J.

1999-04-13

The present invention discloses a process for removing undesired particles from a gas stream including the steps of contacting a composition containing an adhesive with the gas stream; collecting the undesired particles and adhesive on a collection surface to form an aggregate comprising the adhesive and undesired particles on the collection surface; and removing the agglomerate from the collection zone. The composition may then be atomized and injected into the gas stream. The composition may include a liquid that vaporizes in the gas stream. After the liquid vaporizes, adhesive particles are entrained in the gas stream. The process may be applied to electrostatic precipitators and filtration systems to improve undesired particle collection efficiency. 5 figs.

Method and apparatus for decreased undesired particle emissions in gas streams

DOEpatents

Durham, Michael Dean; Schlager, Richard John; Ebner, Timothy George; Stewart, Robin Michele; Bustard, Cynthia Jean

1999-01-01

The present invention discloses a process for removing undesired particles from a gas stream including the steps of contacting a composition containing an adhesive with the gas stream; collecting the undesired particles and adhesive on a collection surface to form an aggregate comprising the adhesive and undesired particles on the collection surface; and removing the agglomerate from the collection zone. The composition may then be atomized and injected into the gas stream. The composition may include a liquid that vaporizes in the gas stream. After the liquid vaporizes, adhesive particles are entrained in the gas stream. The process may be applied to electrostatic precipitators and filtration systems to improve undesired particle collection efficiency.

Method for removing undesired particles from gas streams

DOEpatents

Durham, Michael Dean; Schlager, Richard John; Ebner, Timothy George; Stewart, Robin Michele; Hyatt, David E.; Bustard, Cynthia Jean; Sjostrom, Sharon

1998-01-01

The present invention discloses a process for removing undesired particles from a gas stream including the steps of contacting a composition containing an adhesive with the gas stream; collecting the undesired particles and adhesive on a collection surface to form an aggregate comprising the adhesive and undesired particles on the collection surface; and removing the agglomerate from the collection zone. The composition may then be atomized and injected into the gas stream. The composition may include a liquid that vaporizes in the gas stream. After the liquid vaporizes, adhesive particles are entrained in the gas stream. The process may be applied to electrostatic precipitators and filtration systems to improve undesired particle collection efficiency.

Process and system for removing impurities from a gas

DOEpatents

Henningsen, Gunnar; Knowlton, Teddy Merrill; Findlay, John George; Schlather, Jerry Neal; Turk, Brian S

2014-04-15

A fluidized reactor system for removing impurities from a gas and an associated process are provided. The system includes a fluidized absorber for contacting a feed gas with a sorbent stream to reduce the impurity content of the feed gas; a fluidized solids regenerator for contacting an impurity loaded sorbent stream with a regeneration gas to reduce the impurity content of the sorbent stream; a first non-mechanical gas seal forming solids transfer device adapted to receive an impurity loaded sorbent stream from the absorber and transport the impurity loaded sorbent stream to the regenerator at a controllable flow rate in response to an aeration gas; and a second non-mechanical gas seal forming solids transfer device adapted to receive a sorbent stream of reduced impurity content from the regenerator and transfer the sorbent stream of reduced impurity content to the absorber without changing the flow rate of the sorbent stream.

Tracking Training-Related Plasticity by Combining fMRI and DTI: The Right Hemisphere Ventral Stream Mediates Musical Syntax Processing.

PubMed

Oechslin, Mathias S; Gschwind, Markus; James, Clara E

2018-04-01

As a functional homolog for left-hemispheric syntax processing in language, neuroimaging studies evidenced involvement of right prefrontal regions in musical syntax processing, of which underlying white matter connectivity remains unexplored so far. In the current experiment, we investigated the underlying pathway architecture in subjects with 3 levels of musical expertise. Employing diffusion tensor imaging tractography, departing from seeds from our previous functional magnetic resonance imaging study on music syntax processing in the same participants, we identified a pathway in the right ventral stream that connects the middle temporal lobe with the inferior frontal cortex via the extreme capsule, and corresponds to the left hemisphere ventral stream, classically attributed to syntax processing in language comprehension. Additional morphometric consistency analyses allowed dissociating tract core from more dispersed fiber portions. Musical expertise related to higher tract consistency of the right ventral stream pathway. Specifically, tract consistency in this pathway predicted the sensitivity for musical syntax violations. We conclude that enduring musical practice sculpts ventral stream architecture. Our results suggest that training-related pathway plasticity facilitates the right hemisphere ventral stream information transfer, supporting an improved sound-to-meaning mapping in music.

Data Streams: An Overview and Scientific Applications

NASA Astrophysics Data System (ADS)

Aggarwal, Charu C.

In recent years, advances in hardware technology have facilitated the ability to collect data continuously. Simple transactions of everyday life such as using a credit card, a phone, or browsing the web lead to automated data storage. Similarly, advances in information technology have lead to large flows of data across IP networks. In many cases, these large volumes of data can be mined for interesting and relevant information in a wide variety of applications. When the volume of the underlying data is very large, it leads to a number of computational and mining challenges: With increasing volume of the data, it is no longer possible to process the data efficiently by using multiple passes. Rather, one can process a data item at most once. This leads to constraints on the implementation of the underlying algorithms. Therefore, stream mining algorithms typically need to be designed so that the algorithms work with one pass of the data. In most cases, there is an inherent temporal component to the stream mining process. This is because the data may evolve over time. This behavior of data streams is referred to as temporal locality. Therefore, a straightforward adaptation of one-pass mining algorithms may not be an effective solution to the task. Stream mining algorithms need to be carefully designed with a clear focus on the evolution of the underlying data. Another important characteristic of data streams is that they are often mined in a distributed fashion. Furthermore, the individual processors may have limited processing and memory. Examples of such cases include sensor networks, in which it may be desirable to perform in-network processing of data stream with limited processing and memory [1, 2]. This chapter will provide an overview of the key challenges in stream mining algorithms which arise from the unique setup in which these problems are encountered. This chapter is organized as follows. In the next section, we will discuss the generic challenges that stream mining poses to a variety of data management and data mining problems. The next section also deals with several issues which arise in the context of data stream management. In Sect. 3, we discuss several mining algorithms on the data stream model. Section 4 discusses various scientific applications of data streams. Section 5 discusses the research directions and conclusions.

Role of submerged vegetation in the retention processes of three plant protection products in flow-through stream mesocosms.

PubMed

Stang, Christoph; Wieczorek, Matthias Valentin; Noss, Christian; Lorke, Andreas; Scherr, Frank; Goerlitz, Gerhard; Schulz, Ralf

2014-07-01

Quantitative information on the processes leading to the retention of plant protection products (PPPs) in surface waters is not available, particularly for flow-through systems. The influence of aquatic vegetation on the hydraulic- and sorption-mediated mitigation processes of three PPPs (triflumuron, pencycuron, and penflufen; logKOW 3.3-4.9) in 45-m slow-flowing stream mesocosms was investigated. Peak reductions were 35-38% in an unvegetated stream mesocosm, 60-62% in a sparsely vegetated stream mesocosm (13% coverage with Elodea nuttallii), and in a similar range of 57-69% in a densely vegetated stream mesocosm (100% coverage). Between 89% and 93% of the measured total peak reductions in the sparsely vegetated stream can be explained by an increase of vegetation-induced dispersion (estimated with the one-dimensional solute transport model OTIS), while 7-11% of the peak reduction can be attributed to sorption processes. However, dispersion contributed only 59-71% of the peak reductions in the densely vegetated stream mesocosm, where 29% to 41% of the total peak reductions can be attributed to sorption processes. In the densely vegetated stream, 8-27% of the applied PPPs, depending on the logKOW values of the compounds, were temporarily retained by macrophytes. Increasing PPP recoveries in the aqueous phase were accompanied by a decrease of PPP concentrations in macrophytes indicating kinetic desorption over time. This is the first study to provide quantitative data on how the interaction of dispersion and sorption, driven by aquatic macrophytes, influences the mitigation of PPP concentrations in flowing vegetated stream systems. Copyright © 2014 Elsevier Ltd. All rights reserved.

Process for the physical segregation of minerals

DOEpatents

Yingling, Jon C.; Ganguli, Rajive

2004-01-06

With highly heterogeneous groups or streams of minerals, physical segregation using online quality measurements is an economically important first stage of the mineral beneficiation process. Segregation enables high quality fractions of the stream to bypass processing, such as cleaning operations, thereby reducing the associated costs and avoiding the yield losses inherent in any downstream separation process. The present invention includes various methods for reliably segregating a mineral stream into at least one fraction meeting desired quality specifications while at the same time maximizing yield of that fraction.

Analytic Strategies of Streaming Data for eHealth.

PubMed

Yoon, Sunmoo

2016-01-01

New analytic strategies for streaming big data from wearable devices and social media are emerging in ehealth. We face challenges to find meaningful patterns from big data because researchers face difficulties to process big volume of streaming data using traditional processing applications.1 This introductory 180 minutes tutorial offers hand-on instruction on analytics2 (e.g., topic modeling, social network analysis) of streaming data. This tutorial aims to provide practical strategies of information on reducing dimensionality using examples of big data. This tutorial will highlight strategies of incorporating domain experts and a comprehensive approach to streaming social media data.

Nitrogen processing by grazers in a headwater stream: riparian connections

DOE PAGES

Hill, Walter R.; Griffiths, Natalie A.

2016-10-19

Primary consumers play important roles in the cycling of nutrients in headwater streams, storing assimilated nutrients in growing tissue and recycling them through excretion. Though environmental conditions in most headwater streams and their surrounding terrestrial ecosystems vary considerably over the course of a year, relatively little is known about the effects of seasonality on consumer nutrient recycling these streams. Here, we measured nitrogen accumulated through growth and excreted by the grazing snail Elimia clavaeformis (Pleuroceridae) over the course of 12 months in Walker Branch, identifying close connections between in-stream nitrogen processing and seasonal changes in the surrounding forest.

Method and apparatus for separation of heavy and tritiated water

DOEpatents

Lee, Myung W.

2001-01-01

The present invention is a bi-thermal membrane process for separating and recovering hydrogen isotopes from a fluid containing hydrogen isotopes, such as water and hydrogen gas. The process in accordance with the present invention provides counter-current cold and hot streams of the fluid separated with a thermally insulating and chemically transparent proton exchange membrane (PEM). The two streams exchange hydrogen isotopes through the membrane: the heavier isotopes migrate into the cold stream, while the lighter isotopes migrate into the hot stream. The heavy and light isotopes are continuously withdrawn from the cold and hot streams respectively.

A multistream model of visual word recognition.

PubMed

Allen, Philip A; Smith, Albert F; Lien, Mei-Ching; Kaut, Kevin P; Canfield, Angie

2009-02-01

Four experiments are reported that test a multistream model of visual word recognition, which associates letter-level and word-level processing channels with three known visual processing streams isolated in macaque monkeys: the magno-dominated (MD) stream, the interblob-dominated (ID) stream, and the blob-dominated (BD) stream (Van Essen & Anderson, 1995). We show that mixing the color of adjacent letters of words does not result in facilitation of response times or error rates when the spatial-frequency pattern of a whole word is familiar. However, facilitation does occur when the spatial-frequency pattern of a whole word is not familiar. This pattern of results is not due to different luminance levels across the different-colored stimuli and the background because isoluminant displays were used. Also, the mixed-case, mixed-hue facilitation occurred when different display distances were used (Experiments 2 and 3), so this suggests that image normalization can adjust independently of object size differences. Finally, we show that this effect persists in both spaced and unspaced conditions (Experiment 4)--suggesting that inappropriate letter grouping by hue cannot account for these results. These data support a model of visual word recognition in which lower spatial frequencies are processed first in the more rapid MD stream. The slower ID and BD streams may process some lower spatial frequency information in addition to processing higher spatial frequency information, but these channels tend to lose the processing race to recognition unless the letter string is unfamiliar to the MD stream--as with mixed-case presentation.

COLA: Optimizing Stream Processing Applications via Graph Partitioning

NASA Astrophysics Data System (ADS)

Khandekar, Rohit; Hildrum, Kirsten; Parekh, Sujay; Rajan, Deepak; Wolf, Joel; Wu, Kun-Lung; Andrade, Henrique; Gedik, Buğra

In this paper, we describe an optimization scheme for fusing compile-time operators into reasonably-sized run-time software units called processing elements (PEs). Such PEs are the basic deployable units in System S, a highly scalable distributed stream processing middleware system. Finding a high quality fusion significantly benefits the performance of streaming jobs. In order to maximize throughput, our solution approach attempts to minimize the processing cost associated with inter-PE stream traffic while simultaneously balancing load across the processing hosts. Our algorithm computes a hierarchical partitioning of the operator graph based on a minimum-ratio cut subroutine. We also incorporate several fusion constraints in order to support real-world System S jobs. We experimentally compare our algorithm with several other reasonable alternative schemes, highlighting the effectiveness of our approach.

Source Apportionment of Suspended Sediment Sources using 137Cs and 210Pbxs

NASA Astrophysics Data System (ADS)

Lamba, J.; Karthikeyan, K.; Thompson, A.

2017-12-01

A study was conducted in the Pleasant Valley Watershed (50 km 2) in South Central Wisconsin to better understand sediment transport processes using sediment fingerprinting technique. Previous studies conducted in this watershed showed that resuspension of fine sediment deposited on the stream bed is an important source of suspended sediment. To better understand the role of fine sediment deposited on the stream bed, fallout radionuclides,137Cs and 210Pbxs were used to determine relative contribution to suspended sediment from in-stream (stream bank and stream bed) and upland sediment sources. Suspended sediment samples were collected during the crop growing season. Potential sources of suspended sediment considered in this study included cropland, pasture and in-stream (stream bed and stream bank). Suspended sediment sources were determined at a subwatershed level. Results of this study showed that in-stream sediment sources are important sources of suspended sediment. Future research should be conducted to better understand the role of legacy sediment in watershed-level sediment transport processes.

Stream-related preferences of inputs to the superior colliculus from areas of dorsal and ventral streams of mouse visual cortex.

PubMed

Wang, Quanxin; Burkhalter, Andreas

2013-01-23

Previous studies of intracortical connections in mouse visual cortex have revealed two subnetworks that resemble the dorsal and ventral streams in primates. Although calcium imaging studies have shown that many areas of the ventral stream have high spatial acuity whereas areas of the dorsal stream are highly sensitive for transient visual stimuli, there are some functional inconsistencies that challenge a simple grouping into "what/perception" and "where/action" streams known in primates. The superior colliculus (SC) is a major center for processing of multimodal sensory information and the motor control of orienting the eyes, head, and body. Visual processing is performed in superficial layers, whereas premotor activity is generated in deep layers of the SC. Because the SC is known to receive input from visual cortex, we asked whether the projections from 10 visual areas of the dorsal and ventral streams terminate in differential depth profiles within the SC. We found that inputs from primary visual cortex are by far the strongest. Projections from the ventral stream were substantially weaker, whereas the sparsest input originated from areas of the dorsal stream. Importantly, we found that ventral stream inputs terminated in superficial layers, whereas dorsal stream inputs tended to be patchy and either projected equally to superficial and deep layers or strongly preferred deep layers. The results suggest that the anatomically defined ventral and dorsal streams contain areas that belong to distinct functional systems, specialized for the processing of visual information and visually guided action, respectively.

40 CFR 65.149 - Boilers and process heaters.

Code of Federal Regulations, 2010 CFR

2010-07-01

... stream is not introduced as or with the primary fuel, a temperature monitoring device in the fire box...-throughput transfer racks, as applicable, shall meet the requirements of this section. (2) The vent stream... thermal units per hour) or greater. (ii) A boiler or process heater into which the vent stream is...

40 CFR 63.1082 - What definitions do I need to know?

Code of Federal Regulations, 2011 CFR

2011-07-01

... includes direct-contact cooling water. Spent caustic waste stream means the continuously flowing process... compounds from process streams, typically cracked gas. The spent caustic waste stream does not include spent..., and the C4 butadiene storage equipment; and spent wash water from the C4 crude butadiene carbonyl wash...

40 CFR 63.1082 - What definitions do I need to know?

Code of Federal Regulations, 2012 CFR

2012-07-01

... includes direct-contact cooling water. Spent caustic waste stream means the continuously flowing process... compounds from process streams, typically cracked gas. The spent caustic waste stream does not include spent..., and the C4 butadiene storage equipment; and spent wash water from the C4 crude butadiene carbonyl wash...

40 CFR 63.1082 - What definitions do I need to know?

Code of Federal Regulations, 2014 CFR

2014-07-01

... includes direct-contact cooling water. Spent caustic waste stream means the continuously flowing process... compounds from process streams, typically cracked gas. The spent caustic waste stream does not include spent..., and the C4 butadiene storage equipment; and spent wash water from the C4 crude butadiene carbonyl wash...

40 CFR 63.1082 - What definitions do I need to know?

Code of Federal Regulations, 2013 CFR

2013-07-01

... includes direct-contact cooling water. Spent caustic waste stream means the continuously flowing process... compounds from process streams, typically cracked gas. The spent caustic waste stream does not include spent..., and the C4 butadiene storage equipment; and spent wash water from the C4 crude butadiene carbonyl wash...

M-Stream Deficits and Reading-Related Visual Processes in Developmental Dyslexia

ERIC Educational Resources Information Center

Boden, Catherine; Giaschi, Deborah

2007-01-01

Some visual processing deficits in developmental dyslexia have been attributed to abnormalities in the subcortical M stream and/or the cortical dorsal stream of the visual pathways. The nature of the relationship between these visual deficits and reading is unknown. The purpose of the present article was to characterize reading-related perceptual…

Streaming data analytics via message passing with application to graph algorithms

DOE PAGES

Plimpton, Steven J.; Shead, Tim

2014-05-06

The need to process streaming data, which arrives continuously at high-volume in real-time, arises in a variety of contexts including data produced by experiments, collections of environmental or network sensors, and running simulations. Streaming data can also be formulated as queries or transactions which operate on a large dynamic data store, e.g. a distributed database. We describe a lightweight, portable framework named PHISH which enables a set of independent processes to compute on a stream of data in a distributed-memory parallel manner. Datums are routed between processes in patterns defined by the application. PHISH can run on top of eithermore » message-passing via MPI or sockets via ZMQ. The former means streaming computations can be run on any parallel machine which supports MPI; the latter allows them to run on a heterogeneous, geographically dispersed network of machines. We illustrate how PHISH can support streaming MapReduce operations, and describe streaming versions of three algorithms for large, sparse graph analytics: triangle enumeration, subgraph isomorphism matching, and connected component finding. Lastly, we also provide benchmark timings for MPI versus socket performance of several kernel operations useful in streaming algorithms.« less

Method and apparatus for producing oxygen and nitrogen and membrane therefor

DOEpatents

Roman, I.C.; Baker, R.W.

1985-09-17

Process and apparatus for the separation and purification of oxygen and nitrogen as well as a novel membrane useful therein are disclosed. The process utilizes novel facilitated transport membranes to selectively transport oxygen from one gaseous stream to another, leaving nitrogen as a byproduct. In the method, an oxygen carrier capable of reversibly binding molecular oxygen is dissolved in a polar organic membrane which separates a gaseous feed stream such as atmospheric air and a gaseous product stream. The feed stream is maintained at a sufficiently high oxygen pressure to keep the oxygen carrier in its oxygenated form at the interface of the feed stream with the membrane, while the product stream is maintained at a sufficiently low oxygen pressure to keep the carrier in its deoxygenated form at the interface of the product stream with the membrane. In an alternate mode of operation, the feed stream is maintained at a sufficiently low temperature and high oxygen pressure to keep the oxygen carrier in its oxygenated form at the interface of the feed stream with the membrane and the product stream is maintained at a sufficiently high temperature to keep the carrier in its deoxygenated form at the interface of the product stream with the membrane. Under such conditions, the carrier acts as a shuttle, picking up oxygen at the feed side of the membrane, diffusing across the membrane as the oxygenated complex, releasing oxygen to the product stream, and then diffusing back to the feed side to repeat the process. Exceptionally and unexpectedly high O[sub 2]/N[sub 2] selectivity, on the order of 10 to 30, is obtained, as well as exceptionally high oxygen permeability, on the order of 6 to 15 [times] 10[sup [minus]8] cm[sup 3]-cm/cm[sup 2]-sec-cmHg, as well as a long membrane life of in excess of 3 months, making the process commercially feasible. 2 figs.

Method and apparatus for producing oxygen and nitrogen and membrane therefor

DOEpatents

Roman, Ian C.; Baker, Richard W.

1985-01-01

Process and apparatus for the separation and purification of oxygen and nitrogen as well as a novel membrane useful therein are disclosed. The process utilizes novel facilitated transport membranes to selectively transport oxygen from one gaseous stream to another, leaving nitrogen as a byproduct. In the method, an oxygen carrier capable of reversibly binding molecular oxygen is dissolved in a polar organic membrane which separates a gaseous feed stream such as atmospheric air and a gaseous product stream. The feed stream is maintained at a sufficiently high oxygen pressure to keep the oxygen carrier in its oxygenated form at the interface of the feed stream with the membrane, while the product stream is maintained at a sufficiently low oxygen pressure to keep the carrier in its deoxygenated form at the interface of the product stream with the membrane. In an alternate mode of operation, the feed stream is maintained at a sufficiently low temperature and high oxygen pressure to keep the oxygen carrier in its oxygenated form at the interface of the feed stream with the membrane and the product stream is maintained at a sufficiently high temperature to keep the carrier in its deoxygenated form at the interface of the product stream with the membrane. Under such conditions, the carrier acts as a shuttle, picking up oxygen at the feed side of the membrane, diffusing across the membrane as the oxygenated complex, releasing oxygen to the product stream, and then diffusing back to the feed side to repeat the process. Exceptionally and unexpectedly high O.sub.2 /N.sub.2 selectivity, on the order of 10 to 30, is obtained, as well as exceptionally high oxygen permeability, on the order of 6 to 15.times.10.sup.-8 cm.sup.3 -cm/cm.sup.2 -sec-cmHg, as well as a long membrane life of in excess of 3 months, making the process commercially feasible.

40 CFR 63.11970 - What are my initial compliance requirements for process wastewater?

Code of Federal Regulations, 2014 CFR

2014-07-01

... requirements for process wastewater? 63.11970 Section 63.11970 Protection of Environment ENVIRONMENTAL... What are my initial compliance requirements for process wastewater? (a) Demonstration of initial compliance for process wastewater streams that must be treated. For each process wastewater stream that must...

40 CFR 63.11970 - What are my initial compliance requirements for process wastewater?

Code of Federal Regulations, 2013 CFR

2013-07-01

... requirements for process wastewater? 63.11970 Section 63.11970 Protection of Environment ENVIRONMENTAL... What are my initial compliance requirements for process wastewater? (a) Demonstration of initial compliance for process wastewater streams that must be treated. For each process wastewater stream that must...

40 CFR 63.11970 - What are my initial compliance requirements for process wastewater?

Code of Federal Regulations, 2012 CFR

2012-07-01

... requirements for process wastewater? 63.11970 Section 63.11970 Protection of Environment ENVIRONMENTAL... What are my initial compliance requirements for process wastewater? (a) Demonstration of initial compliance for process wastewater streams that must be treated. For each process wastewater stream that must...

Integrating complex business processes for knowledge-driven clinical decision support systems.

PubMed

Kamaleswaran, Rishikesan; McGregor, Carolyn

2012-01-01

This paper presents in detail the component of the Complex Business Process for Stream Processing framework that is responsible for integrating complex business processes to enable knowledge-driven Clinical Decision Support System (CDSS) recommendations. CDSSs aid the clinician in supporting the care of patients by providing accurate data analysis and evidence-based recommendations. However, the incorporation of a dynamic knowledge-management system that supports the definition and enactment of complex business processes and real-time data streams has not been researched. In this paper we discuss the process web service as an innovative method of providing contextual information to a real-time data stream processing CDSS.

Method for processing aqueous wastes

DOEpatents

Pickett, John B.; Martin, Hollis L.; Langton, Christine A.; Harley, Willie W.

1993-01-01

A method for treating waste water such as that from an industrial processing facility comprising the separation of the waste water into a dilute waste stream and a concentrated waste stream. The concentrated waste stream is treated chemically to enhance precipitation and then allowed to separate into a sludge and a supernate. The supernate is skimmed or filtered from the sludge and blended with the dilute waste stream to form a second dilute waste stream. The sludge remaining is mixed with cementitious material, rinsed to dissolve soluble components, then pressed to remove excess water and dissolved solids before being allowed to cure. The dilute waste stream is also chemically treated to decompose carbonate complexes and metal ions and then mixed with cationic polymer to cause the precipitated solids to flocculate. Filtration of the flocculant removes sufficient solids to allow the waste water to be discharged to the surface of a stream. The filtered material is added to the sludge of the concentrated waste stream. The method is also applicable to the treatment and removal of soluble uranium from aqueous streams, such that the treated stream may be used as a potable water supply.

Integration and segregation in auditory scene analysis

NASA Astrophysics Data System (ADS)

Sussman, Elyse S.

2005-03-01

Assessment of the neural correlates of auditory scene analysis, using an index of sound change detection that does not require the listener to attend to the sounds [a component of event-related brain potentials called the mismatch negativity (MMN)], has previously demonstrated that segregation processes can occur without attention focused on the sounds and that within-stream contextual factors influence how sound elements are integrated and represented in auditory memory. The current study investigated the relationship between the segregation and integration processes when they were called upon to function together. The pattern of MMN results showed that the integration of sound elements within a sound stream occurred after the segregation of sounds into independent streams and, further, that the individual streams were subject to contextual effects. These results are consistent with a view of auditory processing that suggests that the auditory scene is rapidly organized into distinct streams and the integration of sequential elements to perceptual units takes place on the already formed streams. This would allow for the flexibility required to identify changing within-stream sound patterns, needed to appreciate music or comprehend speech..

Processing reafferent and exafferent visual information for action and perception.

PubMed

Reichenbach, Alexandra; Diedrichsen, Jörn

2015-01-01

A recent study suggests that reafferent hand-related visual information utilizes a privileged, attention-independent processing channel for motor control. This process was termed visuomotor binding to reflect its proposed function: linking visual reafferences to the corresponding motor control centers. Here, we ask whether the advantage of processing reafferent over exafferent visual information is a specific feature of the motor processing stream or whether the improved processing also benefits the perceptual processing stream. Human participants performed a bimanual reaching task in a cluttered visual display, and one of the visual hand cursors could be displaced laterally during the movement. We measured the rapid feedback responses of the motor system as well as matched perceptual judgments of which cursor was displaced. Perceptual judgments were either made by watching the visual scene without moving or made simultaneously to the reaching tasks, such that the perceptual processing stream could also profit from the specialized processing of reafferent information in the latter case. Our results demonstrate that perceptual judgments in the heavily cluttered visual environment were improved when performed based on reafferent information. Even in this case, however, the filtering capability of the perceptual processing stream suffered more from the increasing complexity of the visual scene than the motor processing stream. These findings suggest partly shared and partly segregated processing of reafferent information for vision for motor control versus vision for perception.

Geomorphic variation in riparian tree mortality and stream coarse woody debris recruitment from record flooding in a coastal plain stream

Treesearch

Brian J. Palik; Stephen W. Golladay; P. Charles Goebel; Brad W. Taylor

1998-01-01

Large floods are an important process controlling the structure and function of stream ecosystems. One of the ways floods affect streams is through the recruitment of coarse woody debris from stream-side forests. Stream valley geomorphology may mediate this interaction by altering flood velocity, depth, and duration. Little research has examined how floods and...

A new neural framework for visuospatial processing.

PubMed

Kravitz, Dwight J; Saleem, Kadharbatcha S; Baker, Chris I; Mishkin, Mortimer

2011-04-01

The division of cortical visual processing into distinct dorsal and ventral streams is a key framework that has guided visual neuroscience. The characterization of the ventral stream as a 'What' pathway is relatively uncontroversial, but the nature of dorsal stream processing is less clear. Originally proposed as mediating spatial perception ('Where'), more recent accounts suggest it primarily serves non-conscious visually guided action ('How'). Here, we identify three pathways emerging from the dorsal stream that consist of projections to the prefrontal and premotor cortices, and a major projection to the medial temporal lobe that courses both directly and indirectly through the posterior cingulate and retrosplenial cortices. These three pathways support both conscious and non-conscious visuospatial processing, including spatial working memory, visually guided action and navigation, respectively.

The ecology and biogeochemistry of stream biofilms.

PubMed

Battin, Tom J; Besemer, Katharina; Bengtsson, Mia M; Romani, Anna M; Packmann, Aaron I

2016-04-01

Streams and rivers form dense networks, shape the Earth's surface and, in their sediments, provide an immensely large surface area for microbial growth. Biofilms dominate microbial life in streams and rivers, drive crucial ecosystem processes and contribute substantially to global biogeochemical fluxes. In turn, water flow and related deliveries of nutrients and organic matter to biofilms constitute major constraints on microbial life. In this Review, we describe the ecology and biogeochemistry of stream biofilms and highlight the influence of physical and ecological processes on their structure and function. Recent advances in the study of biofilm ecology may pave the way towards a mechanistic understanding of the effects of climate and environmental change on stream biofilms and the biogeochemistry of stream ecosystems.

Cooling and solidification of heavy hydrocarbon liquid streams

DOEpatents

Antieri, Salvatore J.; Comolli, Alfred G.

1983-01-01

A process and apparatus for cooling and solidifying a stream of heavy hydrocarbon material normally boiling above about 850.degree. F., such as vacuum bottoms material from a coal liquefaction process. The hydrocarbon stream is dropped into a liquid bath, preferably water, which contains a screw conveyor device and the stream is rapidly cooled, solidified and broken therein to form discrete elongated particles. The solid extrudates or prills are then dried separately to remove substantially all surface moisture, and passed to further usage.

Electrophysiological Evidence for Ventral Stream Deficits in Schizophrenia Patients

PubMed Central

Plomp, Gijs; Roinishvili, Maya; Chkonia, Eka; Kapanadze, George; Kereselidze, Maia; Brand, Andreas; Herzog, Michael H.

2013-01-01

Schizophrenic patients suffer from many deficits including visual, attentional, and cognitive ones. Visual deficits are of particular interest because they are at the fore-end of information processing and can provide clear examples of interactions between sensory, perceptual, and higher cognitive functions. Visual deficits in schizophrenic patients are often attributed to impairments in the dorsal (where) rather than the ventral (what) stream of visual processing. We used a visual-masking paradigm in which patients and matched controls discriminated small vernier offsets. We analyzed the evoked electroencephalography (EEG) responses and applied distributed electrical source imaging techniques to estimate activity differences between conditions and groups throughout the brain. Compared with controls, patients showed strongly reduced discrimination accuracy, confirming previous work. The behavioral deficits corresponded to pronounced decreases in the evoked EEG response at around 200 ms after stimulus onset. At this latency, patients showed decreased activity for targets in left parietal cortex (dorsal stream), but the decrease was most pronounced in lateral occipital cortex (in the ventral stream). These deficiencies occurred at latencies that reflect object processing and fine shape discriminations. We relate the reduced ventral stream activity to deficient top-down processing of target stimuli and provide a framework for relating the commonly observed dorsal stream deficiencies with the currently observed ventral stream deficiencies. PMID:22258884

Electrophysiological evidence for ventral stream deficits in schizophrenia patients.

PubMed

Plomp, Gijs; Roinishvili, Maya; Chkonia, Eka; Kapanadze, George; Kereselidze, Maia; Brand, Andreas; Herzog, Michael H

2013-05-01

Schizophrenic patients suffer from many deficits including visual, attentional, and cognitive ones. Visual deficits are of particular interest because they are at the fore-end of information processing and can provide clear examples of interactions between sensory, perceptual, and higher cognitive functions. Visual deficits in schizophrenic patients are often attributed to impairments in the dorsal (where) rather than the ventral (what) stream of visual processing. We used a visual-masking paradigm in which patients and matched controls discriminated small vernier offsets. We analyzed the evoked electroencephalography (EEG) responses and applied distributed electrical source imaging techniques to estimate activity differences between conditions and groups throughout the brain. Compared with controls, patients showed strongly reduced discrimination accuracy, confirming previous work. The behavioral deficits corresponded to pronounced decreases in the evoked EEG response at around 200 ms after stimulus onset. At this latency, patients showed decreased activity for targets in left parietal cortex (dorsal stream), but the decrease was most pronounced in lateral occipital cortex (in the ventral stream). These deficiencies occurred at latencies that reflect object processing and fine shape discriminations. We relate the reduced ventral stream activity to deficient top-down processing of target stimuli and provide a framework for relating the commonly observed dorsal stream deficiencies with the currently observed ventral stream deficiencies.

40 CFR 63.11940 - What continuous monitoring requirements must I meet for control devices required to install CPMS...

Code of Federal Regulations, 2012 CFR

2012-07-01

... consistent with the manufacturer's recommendations within 15 days or by the next time any process vent stream... the manufacturer's recommendations within 15 days or by the next time any process vent stream is...) Determine gas stream flow using the design blower capacity, with appropriate adjustments for pressure drop...

Carbon dioxide removal process

DOEpatents

Baker, Richard W.; Da Costa, Andre R.; Lokhandwala, Kaaeid A.

2003-11-18

A process and apparatus for separating carbon dioxide from gas, especially natural gas, that also contains C.sub.3+ hydrocarbons. The invention uses two or three membrane separation steps, optionally in conjunction with cooling/condensation under pressure, to yield a lighter, sweeter product natural gas stream, and/or a carbon dioxide stream of reinjection quality and/or a natural gas liquids (NGL) stream.

Interaction of Substrate and Nutrient Availability on wood Biofilm Processes in Streams

Treesearch

Jennifer L. Tank; J.R. Webster

1998-01-01

We examined the effect of decomposing leaf litter and dissolved inorganic nutrients on the heterotrophic biofilm of submerged wood in streams with and without leaves. Leaf litter was excluded from one headwater stream in August 1993 at Coweeta Hydrologic Laboratory in the southern Appalachian Mountains. We compared microbial processes on wood in the litter-excluded...

Liquid additives for particulate emissions control

DOEpatents

Durham, Michael Dean; Schlager, Richard John; Ebner, Timothy George; Stewart, Robin Michele; Hyatt, David E.; Bustard, Cynthia Jean; Sjostrom, Sharon

1999-01-01

The present invention discloses a process for removing undesired particles from a gas stream including the steps of contacting a composition containing an adhesive with the gas stream; collecting the undesired particles and adhesive on a collection surface to form an aggregate comprising the adhesive and undesired particles on the collection surface; and removing the agglomerate from the collection zone. The composition may then be atomized and injected into the gas stream. The composition may include a liquid that vaporizes in the gas stream. After the liquid vaporizes, adhesive particles are entrained in the gas stream. The process may be applied to electrostatic precipitators and filtration systems to improve undesired particle collection efficiency.

Continuous online Fourier transform infrared (FT-IR) spectrometry analysis of hydrogen chloride (HCl), carbon dioxide (CO2), and water (H2O) in nitrogen-rich and ethylene-rich streams.

PubMed

Stephenson, Serena; Pollard, Maria; Boit, Kipchirchir

2013-09-01

The prevalence of optical spectroscopy techniques being applied to the online analysis of continuous processes has increased in the past couple of decades. The ability to continuously "watch" changing stream compositions as operating conditions change has proven invaluable to pilot and world-scale manufacturing in the chemical and petrochemical industries. Presented here is an application requiring continuous monitoring of parts per million (ppm) by weight levels of hydrogen chloride (HCl), water (H2O), and carbon dioxide (CO2) in two gas-phase streams, one nitrogen-rich and one ethylene-rich. Because ethylene has strong mid-infrared (IR) absorption, building an IR method capable of quantifying HCl, H2O, and CO2 posed some challenges. A long-path (5.11m) Fourier transform infrared (FT-IR) spectrometer was used in the mid-infrared region between 1800 and 5000 cm(-1), with a 1 cm(-1) resolution and a 10 s spectral update time. Sample cell temperature and pressure were controlled and measured to minimize measurement variability. Models using a modified classical least squares method were developed and validated first in the laboratory and then using the process stream. Analytical models and process sampling conditions were adjusted to minimize interference of ethylene in the ethylene-rich stream. The predictive capabilities of the measurements were ±0.5 ppm for CO2 in either stream; ±1.1 and ±1.3 ppm for H2O in the nitrogen-rich and ethylene-rich streams, respectively; and ±1.0 and ±2.4 ppm for HCl in the nitrogen-rich and ethylene-rich streams, respectively. Continuous operation of the instrument in the process stream was demonstrated using an automated stream switching sample system set to 10 min intervals. Response time for all components of interest was sufficient to acquire representative stream composition data. This setup provides useful insight into the process for troubleshooting and optimizing plant operating conditions.

Alpha-band rhythm modulation under the condition of subliminal face presentation: MEG study.

PubMed

Sakuraba, Satoshi; Kobayashi, Hana; Sakai, Shinya; Yokosawa, Koichi

2013-01-01

The human brain has two streams to process visual information: a dorsal stream and a ventral stream. Negative potential N170 or its magnetic counterpart M170 is known as the face-specific signal originating from the ventral stream. It is possible to present a visual image unconsciously by using continuous flash suppression (CFS), which is a visual masking technique adopting binocular rivalry. In this work, magnetoencephalograms were recorded during presentation of the three invisible images: face images, which are processed by the ventral stream; tool images, which could be processed by the dorsal stream, and a blank image. Alpha-band activities detected by sensors that are sensitive to M170 were compared. The alpha-band rhythm was suppressed more during presentation of face images than during presentation of the blank image (p=.028). The suppression remained for about 1 s after ending presentations. However, no significant difference was observed between tool and other images. These results suggest that alpha-band rhythm can be modulated also by unconscious visual images.

StreamQRE: Modular Specification and Efficient Evaluation of Quantitative Queries over Streaming Data.

PubMed

Mamouras, Konstantinos; Raghothaman, Mukund; Alur, Rajeev; Ives, Zachary G; Khanna, Sanjeev

2017-06-01

Real-time decision making in emerging IoT applications typically relies on computing quantitative summaries of large data streams in an efficient and incremental manner. To simplify the task of programming the desired logic, we propose StreamQRE, which provides natural and high-level constructs for processing streaming data. Our language has a novel integration of linguistic constructs from two distinct programming paradigms: streaming extensions of relational query languages and quantitative extensions of regular expressions. The former allows the programmer to employ relational constructs to partition the input data by keys and to integrate data streams from different sources, while the latter can be used to exploit the logical hierarchy in the input stream for modular specifications. We first present the core language with a small set of combinators, formal semantics, and a decidable type system. We then show how to express a number of common patterns with illustrative examples. Our compilation algorithm translates the high-level query into a streaming algorithm with precise complexity bounds on per-item processing time and total memory footprint. We also show how to integrate approximation algorithms into our framework. We report on an implementation in Java, and evaluate it with respect to existing high-performance engines for processing streaming data. Our experimental evaluation shows that (1) StreamQRE allows more natural and succinct specification of queries compared to existing frameworks, (2) the throughput of our implementation is higher than comparable systems (for example, two-to-four times greater than RxJava), and (3) the approximation algorithms supported by our implementation can lead to substantial memory savings.

StreamQRE: Modular Specification and Efficient Evaluation of Quantitative Queries over Streaming Data*

PubMed Central

Mamouras, Konstantinos; Raghothaman, Mukund; Alur, Rajeev; Ives, Zachary G.; Khanna, Sanjeev

2017-01-01

Real-time decision making in emerging IoT applications typically relies on computing quantitative summaries of large data streams in an efficient and incremental manner. To simplify the task of programming the desired logic, we propose StreamQRE, which provides natural and high-level constructs for processing streaming data. Our language has a novel integration of linguistic constructs from two distinct programming paradigms: streaming extensions of relational query languages and quantitative extensions of regular expressions. The former allows the programmer to employ relational constructs to partition the input data by keys and to integrate data streams from different sources, while the latter can be used to exploit the logical hierarchy in the input stream for modular specifications. We first present the core language with a small set of combinators, formal semantics, and a decidable type system. We then show how to express a number of common patterns with illustrative examples. Our compilation algorithm translates the high-level query into a streaming algorithm with precise complexity bounds on per-item processing time and total memory footprint. We also show how to integrate approximation algorithms into our framework. We report on an implementation in Java, and evaluate it with respect to existing high-performance engines for processing streaming data. Our experimental evaluation shows that (1) StreamQRE allows more natural and succinct specification of queries compared to existing frameworks, (2) the throughput of our implementation is higher than comparable systems (for example, two-to-four times greater than RxJava), and (3) the approximation algorithms supported by our implementation can lead to substantial memory savings. PMID:29151821

Remembering the Important Things: Semantic Importance in Stream Reasoning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yan, Rui; Greaves, Mark T.; Smith, William P.

Reasoning and querying over data streams rely on the abil- ity to deliver a sequence of stream snapshots to the processing algo- rithms. These snapshots are typically provided using windows as views into streams and associated window management strategies. Generally, the goal of any window management strategy is to preserve the most im- portant data in the current window and preferentially evict the rest, so that the retained data can continue to be exploited. A simple timestamp- based strategy is rst-in-rst-out (FIFO), in which items are replaced in strict order of arrival. All timestamp-based strategies implicitly assume that a temporalmore » ordering reliably re ects importance to the processing task at hand, and thus that window management using timestamps will maximize the ability of the processing algorithms to deliver accurate interpretations of the stream. In this work, we explore a general no- tion of semantic importance that can be used for window management for streams of RDF data using semantically-aware processing algorithms like deduction or semantic query. Semantic importance exploits the infor- mation carried in RDF and surrounding ontologies for ranking window data in terms of its likely contribution to the processing algorithms. We explore the general semantic categories of query contribution, prove- nance, and trustworthiness, as well as the contribution of domain-specic ontologies. We describe how these categories behave using several con- crete examples. Finally, we consider how a stream window management strategy based on semantic importance could improve overall processing performance, especially as available window sizes decrease.« less

Advances in energy technology; Proceedings of the Eighth Annual UMR-DNR Conference on Energy, University of Missouri-Rolla, Rolla, MO, November 4-7, 1981

NASA Astrophysics Data System (ADS)

Sauer, H. J., Jr.; Hegler, B. E.

1982-11-01

Papers on various topics of energy conservation, new passive solar heating and storage devices, governmental particiaption in developing energy technologies, and the development of diverse energy sources and safety features are presented. Attention is given to recent shifts in the federal and state goverenment roles in energy research, development and economic incentives. The applications of passive solar walls, flat plate collectors and trombe walls as retorfits for houses, institutions, and industries were examined. Attention was given to the implementation of wind power by a zoo and the use of spoilers as speed control devices in a Darrieus wind turbine. Aspects of gasohol, coal, synfuel, and laser-pyrolyzed coal products use are investigated. Finally, the economic, social, and political factors influencing energy system selection are explored, togeter with conservation practices in housing, government, and industry, and new simulators for enhancing nuclear power plant safety.

Stream computing for biomedical signal processing: A QRS complex detection case-study.

PubMed

Murphy, B M; O'Driscoll, C; Boylan, G B; Lightbody, G; Marnane, W P

2015-01-01

Recent developments in "Big Data" have brought significant gains in the ability to process large amounts of data on commodity server hardware. Stream computing is a relatively new paradigm in this area, addressing the need to process data in real time with very low latency. While this approach has been developed for dealing with large scale data from the world of business, security and finance, there is a natural overlap with clinical needs for physiological signal processing. In this work we present a case study of streams processing applied to a typical physiological signal processing problem: QRS detection from ECG data.

The paradox of cooling streams in a warming world: regional climate trends do not parallel variable local trends in stream temperature in the Pacific continental United States

Treesearch

Ivan Arismendi; Sherri L. Johnson; Jason B. Dunham; Roy Haggerty

2012-01-01

Temperature is a fundamentally important driver of ecosystem processes in streams. Recent warming of terrestrial climates around the globe has motivated concern about consequent increases in stream temperature. More specifically, observed trends of increasing air temperature and declining stream flow are widely believed to result in corresponding increases in stream...

High temperature methods for forming oxidizer fuel

DOEpatents

Bravo, Jose Luis [Houston, TX

2011-01-11

A method of treating a formation fluid includes providing formation fluid from a subsurface in situ heat treatment process. The formation fluid is separated to produce a liquid stream and a first gas stream. The first gas stream includes carbon dioxide, hydrogen sulfide, hydrocarbons, hydrogen or mixtures thereof. Molecular oxygen is separated from air to form a molecular oxygen stream comprising molecular oxygen. The first gas stream is combined with the molecular oxygen stream to form a combined stream comprising molecular oxygen and the first gas stream. The combined stream is provided to one or more downhole burners.

Integration and segregation in auditory streaming

NASA Astrophysics Data System (ADS)

Almonte, Felix; Jirsa, Viktor K.; Large, Edward W.; Tuller, Betty

2005-12-01

We aim to capture the perceptual dynamics of auditory streaming using a neurally inspired model of auditory processing. Traditional approaches view streaming as a competition of streams, realized within a tonotopically organized neural network. In contrast, we view streaming to be a dynamic integration process which resides at locations other than the sensory specific neural subsystems. This process finds its realization in the synchronization of neural ensembles or in the existence of informational convergence zones. Our approach uses two interacting dynamical systems, in which the first system responds to incoming acoustic stimuli and transforms them into a spatiotemporal neural field dynamics. The second system is a classification system coupled to the neural field and evolves to a stationary state. These states are identified with a single perceptual stream or multiple streams. Several results in human perception are modelled including temporal coherence and fission boundaries [L.P.A.S. van Noorden, Temporal coherence in the perception of tone sequences, Ph.D. Thesis, Eindhoven University of Technology, The Netherlands, 1975], and crossing of motions [A.S. Bregman, Auditory Scene Analysis: The Perceptual Organization of Sound, MIT Press, 1990]. Our model predicts phenomena such as the existence of two streams with the same pitch, which cannot be explained by the traditional stream competition models. An experimental study is performed to provide proof of existence of this phenomenon. The model elucidates possible mechanisms that may underlie perceptual phenomena.

Process for the displacement of cyanide ions from metal-cyanide complexes

DOEpatents

Smith, Barbara F.; Robinson, Thomas W.

1997-01-01

The present invention relates to water-soluble polymers and the use of such water-soluble polymers in a process for the displacement of the cyanide ions from the metal ions within metal-cyanide complexes. The process waste streams can include metal-cyanide containing electroplating waste streams, mining leach waste streams, mineral processing waste streams, and related metal-cyanide containing waste streams. The metal ions of interest are metals that give very strong complexes with cyanide, mostly iron, nickel, and copper. The physical separation of the water-soluble polymer-metal complex from the cyanide ions can be accomplished through the use of ultrafiltration. Once the metal-cyanide complex is disrupted, the freed cyanide ions can be recovered for reuse or destroyed using available oxidative processes rendering the cyanide nonhazardous. The metal ions are released from the polymer, using dilute acid, metal ion oxidation state adjustment, or competing chelating agents, and collected and recovered or disposed of by appropriate waste management techniques. The water-soluble polymer can then be recycled. Preferred water-soluble polymers include polyethyleneimine and polyethyleneimine having a catechol or hydroxamate group.

Modeling hyporheic zone processes

USGS Publications Warehouse

Runkel, Robert L.; McKnight, Diane M.; Rajaram, Harihar

2003-01-01

Stream biogeochemistry is influenced by the physical and chemical processes that occur in the surrounding watershed. These processes include the mass loading of solutes from terrestrial and atmospheric sources, the physical transport of solutes within the watershed, and the transformation of solutes due to biogeochemical reactions. Research over the last two decades has identified the hyporheic zone as an important part of the stream system in which these processes occur. The hyporheic zone may be loosely defined as the porous areas of the stream bed and stream bank in which stream water mixes with shallow groundwater. Exchange of water and solutes between the stream proper and the hyporheic zone has many biogeochemical implications, due to differences in the chemical composition of surface and groundwater. For example, surface waters are typically oxidized environments with relatively high dissolved oxygen concentrations. In contrast, reducing conditions are often present in groundwater systems leading to low dissolved oxygen concentrations. Further, microbial oxidation of organic materials in groundwater leads to supersaturated concentrations of dissolved carbon dioxide relative to the atmosphere. Differences in surface and groundwater pH and temperature are also common. The hyporheic zone is therefore a mixing zone in which there are gradients in the concentrations of dissolved gasses, the concentrations of oxidized and reduced species, pH, and temperature. These gradients lead to biogeochemical reactions that ultimately affect stream water quality. Due to the complexity of these natural systems, modeling techniques are frequently employed to quantify process dynamics.

Distribution of model uncertainty across multiple data streams

NASA Astrophysics Data System (ADS)

Wutzler, Thomas

2014-05-01

When confronting biogeochemical models with a diversity of observational data streams, we are faced with the problem of weighing the data streams. Without weighing or multiple blocked cost functions, model uncertainty is allocated to the sparse data streams and possible bias in processes that are strongly constraint is exported to processes that are constrained by sparse data streams only. In this study we propose an approach that aims at making model uncertainty a factor of observations uncertainty, that is constant over all data streams. Further we propose an implementation based on Monte-Carlo Markov chain sampling combined with simulated annealing that is able to determine this variance factor. The method is exemplified both with very simple models, artificial data and with an inversion of the DALEC ecosystem carbon model against multiple observations of Howland forest. We argue that the presented approach is able to help and maybe resolve the problem of bias export to sparse data streams.

Apparatus and method for two-stage oxidation of wastes

DOEpatents

Fleischman, Scott D.

1995-01-01

An apparatus and method for oxidizing wastes in a two-stage process. The apparatus includes an oxidation device, a gas-liquid contacting column and an electrocell. In the first stage of the process, wastes are heated in the presence of air to partially oxidize the wastes. The heated wastes produce an off-gas stream containing oxidizable materials. In the second stage, the off-gas stream is cooled and flowed through the contacting column, where the off-gas stream is contacted with an aqueous acid stream containing an oxidizing agent having at least two positive valence states. At least a portion of the oxidizable materials are transferred to the acid stream and destroyed by the oxidizing agent. During oxidation, the valence of the oxidizing agent is decreased from its higher state to its lower state. The acid stream is flowed to the electrocell, where an electric current is applied to the stream to restore the oxidizing agent to its higher valence state. The regenerated acid stream is recycled to the contacting column.

Method for separating water soluble organics from a process stream by aqueous biphasic extraction

DOEpatents

Chaiko, David J.; Mego, William A.

1999-01-01

A method for separating water-miscible organic species from a process stream by aqueous biphasic extraction is provided. An aqueous biphase system is generated by contacting a process stream comprised of water, salt, and organic species with an aqueous polymer solution. The organic species transfer from the salt-rich phase to the polymer-rich phase, and the phases are separated. Next, the polymer is recovered from the loaded polymer phase by selectively extracting the polymer into an organic phase at an elevated temperature, while the organic species remain in a substantially salt-free aqueous solution. Alternatively, the polymer is recovered from the loaded polymer by a temperature induced phase separation (cloud point extraction), whereby the polymer and the organic species separate into two distinct solutions. The method for separating water-miscible organic species is applicable to the treatment of industrial wastewater streams, including the extraction and recovery of complexed metal ions from salt solutions, organic contaminants from mineral processing streams, and colorants from spent dye baths.

Defining the cortical visual systems: "what", "where", and "how"

NASA Technical Reports Server (NTRS)

Creem, S. H.; Proffitt, D. R.; Kaiser, M. K. (Principal Investigator)

2001-01-01

The visual system historically has been defined as consisting of at least two broad subsystems subserving object and spatial vision. These visual processing streams have been organized both structurally as two distinct pathways in the brain, and functionally for the types of tasks that they mediate. The classic definition by Ungerleider and Mishkin labeled a ventral "what" stream to process object information and a dorsal "where" stream to process spatial information. More recently, Goodale and Milner redefined the two visual systems with a focus on the different ways in which visual information is transformed for different goals. They relabeled the dorsal stream as a "how" system for transforming visual information using an egocentric frame of reference in preparation for direct action. This paper reviews recent research from psychophysics, neurophysiology, neuropsychology and neuroimaging to define the roles of the ventral and dorsal visual processing streams. We discuss a possible solution that allows for both "where" and "how" systems that are functionally and structurally organized within the posterior parietal lobe.

A new neural framework for visuospatial processing

PubMed Central

Kravitz, Dwight J.; Saleem, Kadharbatcha S.; Baker, Chris I.; Mishkin, Mortimer

2012-01-01

The division of cortical visual processing into distinct dorsal and ventral streams is a key framework that has guided visual neuroscience. The characterization of the ventral stream as a ‘What’ pathway is relatively uncontroversial, but the nature of dorsal stream processing is less clear. Originally proposed as mediating spatial perception (‘Where’), more recent accounts suggest it primarily serves non-conscious visually guided action (‘How’). Here, we identify three pathways emerging from the dorsal stream that consist of projections to the prefrontal and premotor cortices, and a major projection to the medial temporal lobe that courses both directly and indirectly through the posterior cingulate and retrosplenial cortices. These three pathways support both conscious and non-conscious visuospatial processing, including spatial working memory, visually guided action and navigation, respectively. PMID:21415848

Developing an Environmental Decision Support System for Stream Management: the STREAMES Experience

NASA Astrophysics Data System (ADS)

Riera, J.; Argerich, A.; Comas, J.; Llorens, E.; Martí, E.; Godé, L.; Pargament, D.; Puig, M.; Sabater, F.

2005-05-01

Transferring research knowledge to stream managers is crucial for scientifically sound management. Environmental decision support systems are advocated as an effective means to accomplish this. STREAMES (STream REAach Management: an Expert System) is a decision tree based EDSS prototype developed within the context of an European project as a tool to assist water managers in the diagnosis of problems, detection of causes, and selection of management strategies for coping with stream degradation issues related mostly to excess nutrient availability. STREAMES was developed by a team of scientists, water managers, and experts in knowledge engineering. Although the tool focuses on management at the stream reach scale, it also incorporates a mass-balance catchment nutrient emission model and a simple GIS module. We will briefly present the prototype and share our experience in its development. Emphasis will be placed on the process of knowledge acquisition, the design process, the pitfalls and benefits of the communication between scientists and managers, and the potential for future development of STREAMES, particularly in the context of the EU Water Framework Directive.

Stream Processors

NASA Astrophysics Data System (ADS)

Erez, Mattan; Dally, William J.

Stream processors, like other multi core architectures partition their functional units and storage into multiple processing elements. In contrast to typical architectures, which contain symmetric general-purpose cores and a cache hierarchy, stream processors have a significantly leaner design. Stream processors are specifically designed for the stream execution model, in which applications have large amounts of explicit parallel computation, structured and predictable control, and memory accesses that can be performed at a coarse granularity. Applications in the streaming model are expressed in a gather-compute-scatter form, yielding programs with explicit control over transferring data to and from on-chip memory. Relying on these characteristics, which are common to many media processing and scientific computing applications, stream architectures redefine the boundary between software and hardware responsibilities with software bearing much of the complexity required to manage concurrency, locality, and latency tolerance. Thus, stream processors have minimal control consisting of fetching medium- and coarse-grained instructions and executing them directly on the many ALUs. Moreover, the on-chip storage hierarchy of stream processors is under explicit software control, as is all communication, eliminating the need for complex reactive hardware mechanisms.

Method of synchronizing independent functional unit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Changhoan

A system for synchronizing parallel processing of a plurality of functional processing units (FPU), a first FPU and a first program counter to control timing of a first stream of program instructions issued to the first FPU by advancement of the first program counter; a second FPU and a second program counter to control timing of a second stream of program instructions issued to the second FPU by advancement of the second program counter, the first FPU is in communication with a second FPU to synchronize the issuance of a first stream of program instructions to the second stream ofmore » program instructions and the second FPU is in communication with the first FPU to synchronize the issuance of the second stream program instructions to the first stream of program instructions.« less

Method of synchronizing independent functional unit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Changhoan

2017-05-16

A system for synchronizing parallel processing of a plurality of functional processing units (FPU), a first FPU and a first program counter to control timing of a first stream of program instructions issued to the first FPU by advancement of the first program counter; a second FPU and a second program counter to control timing of a second stream of program instructions issued to the second FPU by advancement of the second program counter, the first FPU is in communication with a second FPU to synchronize the issuance of a first stream of program instructions to the second stream ofmore » program instructions and the second FPU is in communication with the first FPU to synchronize the issuance of the second stream program instructions to the first stream of program instructions.« less

Method of synchronizing independent functional unit

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Changhoan

2017-02-14

A system for synchronizing parallel processing of a plurality of functional processing units (FPU), a first FPU and a first program counter to control timing of a first stream of program instructions issued to the first FPU by advancement of the first program counter; a second FPU and a second program counter to control timing of a second stream of program instructions issued to the second FPU by advancement of the second program counter, the first FPU is in communication with a second FPU to synchronize the issuance of a first stream of program instructions to the second stream ofmore » program instructions and the second FPU is in communication with the first FPU to synchronize the issuance of the second stream program instructions to the first stream of program instructions.« less

Evaluation of Topographic wetness index and catchment characteristics on spatially and temporally variable streams across an elevation gradient

NASA Astrophysics Data System (ADS)

Martin, C.

2017-12-01

Topography can be used to delineate streams and quantify the topographic control on hydrological processes of a watershed because geomorphologic processes have shaped the topography and streams of a catchment over time. Topographic Wetness index (TWI) is a common index used for delineating stream networks by predicting location of saturation excess overland flow, but is also used for other physical attributes of a watershed such as soil moisture, groundwater level, and vegetation patterns. This study evaluates how well TWI works across an elevation gradient and the relationships between the active drainage network of four headwater watersheds at various elevations in the Colorado Front Range to topography, geology, climate, soils, elevation, and vegetation in attempt to determine the controls on streamflow location and duration. The results suggest that streams prefer to flow along a path of least resistance which including faults and permeable lithology. Permeable lithologies created more connectivity of stream networks during higher flows but during lower flows dried up. Streams flowing over impermeable lithologies had longer flow duration. Upslope soil hydraulic conductivity played a role on stream location, where soils with low hydraulic conductivity had longer flow duration than soils with higher hydraulic conductivity.Finally TWI thresholds ranged from 5.95 - 10.3 due to changes in stream length and to factors such as geology and soil. TWI had low accuracy for the lowest elevation site due to the greatest change of stream length. In conclusion, structural geology, upslope soil texture, and the permeability of the underlying lithology influenced where the stream was flowing and for how long. Elevation determines climate which influences the hydrologic processes occurring at the watersheds and therefore affects the duration and timing of streams at different elevations. TWI is an adequate tool for delineating streams because results suggest topography has a primary control on the stream locations, but because intermittent streams change throughout the year a algorithm needs to be created to correspond to snow melt and rain events. Also geology indices and soil indices need be considered in addition to topography to have the most accurate derived stream network.

Leaf breakdown in streams differing in catchment land use

USGS Publications Warehouse

Paul, M.J.; Meyer, J.L.; Couch, C.A.

2006-01-01

1. The impact of changes in land use on stream ecosystem function is poorly understood. We studied leaf breakdown, a fundamental process of stream ecosystems, in streams that represent a range of catchment land use in the Piedmont physiographic province of the south-eastern United States. 2. We placed bags of chalk maple (Acer barbatum) leaves in similar-sized streams in 12 catchments of differing dominant land use: four forested, three agricultural, two suburban and three urban catchments. We measured leaf mass, invertebrate abundance and fungal biomass in leaf bags over time. 3. Leaves decayed significantly faster in agricultural (0.0465 day-1) and urban (0.0474 day-1) streams than in suburban (0.0173 day-1) and forested (0.0100 day-1) streams. Additionally, breakdown rates in the agricultural and urban streams were among the fastest reported for deciduous leaves in any stream. Nutrient concentrations in agricultural streams were significantly higher than in any other land-use type. Fungal biomass associated with leaves was significantly lower in urban streams; while shredder abundance in leaf bags was significantly higher in forested and agricultural streams than in suburban and urban streams. Storm runoff was significantly higher in urban and suburban catchments that had higher impervious surface cover than forested or agricultural catchments. 4. We propose that processes accelerating leaf breakdown in agricultural and urban streams were not the same: faster breakdown in agricultural streams was due to increased biological activity as a result of nutrient enrichment, whereas faster breakdown in urban streams was a result of physical fragmentation resulting from higher storm runoff. ?? 2006 The Authors.

Method for processing aqueous wastes

DOEpatents

Pickett, J.B.; Martin, H.L.; Langton, C.A.; Harley, W.W.

1993-12-28

A method is presented for treating waste water such as that from an industrial processing facility comprising the separation of the waste water into a dilute waste stream and a concentrated waste stream. The concentrated waste stream is treated chemically to enhance precipitation and then allowed to separate into a sludge and a supernate. The supernate is skimmed or filtered from the sludge and blended with the dilute waste stream to form a second dilute waste stream. The sludge remaining is mixed with cementitious material, rinsed to dissolve soluble components, then pressed to remove excess water and dissolved solids before being allowed to cure. The dilute waste stream is also chemically treated to decompose carbonate complexes and metal ions and then mixed with cationic polymer to cause the precipitated solids to flocculate. Filtration of the flocculant removes sufficient solids to allow the waste water to be discharged to the surface of a stream. The filtered material is added to the sludge of the concentrated waste stream. The method is also applicable to the treatment and removal of soluble uranium from aqueous streams, such that the treated stream may be used as a potable water supply. 4 figures.

The Stream Table in Physical Geography Instruction.

ERIC Educational Resources Information Center

Wikle, Thomas A.; Lightfoot, Dale R.

1997-01-01

Outlines a number of activities to be conducted with a stream table (large wooden box filled with sediment and designed for water to pass through) in class. Activities illustrate such fluvial processes as stream meandering, erosion, transportation, and deposition. Includes a diagram for constructing a stream table. (MJP)

THE EMERGING USE OF LIDAR AS A TOOL FOR ASSESSING WATERSHED MORPHOLOGY

EPA Science Inventory

Stream channel morphology is an integral component of the stream fluvial process and is inherently related to the stability of stream aquatic ecology. Numerous studies have shown that changes in stream channel geometry are related to changes in biotic integrity. In urbanizing la...

Ecoregions and stream morphology in eastern Oklahoma

USGS Publications Warehouse

Splinter, D.K.; Dauwalter, D.C.; Marston, R.A.; Fisher, W.L.

2010-01-01

Broad-scale variables (i.e., geology, topography, climate, land use, vegetation, and soils) influence channel morphology. How and to what extent the longitudinal pattern of channel morphology is influenced by broad-scale variables is important to fluvial geomorphologists and stream ecologists. In the last couple of decades, there has been an increase in the amount of interdisciplinary research between fluvial geomorphologists and stream ecologists. In a historical context, fluvial geomorphologists are more apt to use physiographic regions to distinguish broad-scale variables, while stream ecologists are more apt to use the concept of an ecosystem to address the broad-scale variables that influence stream habitat. For this reason, we designed a study using ecoregions, which uses physical and biological variables to understand how landscapes influence channel processes. Ecoregions are delineated by similarities in geology, climate, soils, land use, and potential natural vegetation. In the fluvial system, stream form and function are dictated by processes observed throughout the fluvial hierarchy. Recognizing that stream form and function should differ by ecoregion, a study was designed to evaluate how the characteristics of stream channels differed longitudinally among three ecoregions in eastern Oklahoma, USA: Boston Mountains, Ozark Highlands, and Ouachita Mountains. Channel morphology of 149 stream reaches was surveyed in 1st- through 4th-order streams, and effects of drainage area and ecoregion on channel morphology was evaluated using multiple regressions. Differences existed (?????0.05) among ecoregions for particle size, bankfull width, and width/depth ratio. No differences existed among ecoregions for gradient or sinuosity. Particle size was smallest in the Ozark Highlands and largest in the Ouachita Mountains. Bankfull width was larger in the Ozark Highlands than in the Boston Mountains and Ouachita Mountains in larger streams. Width/depth ratios of the Boston Mountains and Ozark Highlands were not statistically different. Significant differences existed, however, between the Boston Mountains and Ozark Highlands when compared individually to the Ouachita Mountains. We found that ecoregions afforded a good spatial structure that can help in understanding longitudinal trends in stream reach morphology surveyed at the reach scale. The hierarchy of the fluvial system begins within a broad, relatively homogenous setting that imparts control on processes that affect stream function. Ecoregions provide an adequate regional division to begin a large-scale geomorphic study of processes in stream channels. ?? 2010 Elsevier B.V.

Recovery of olefin monomers

DOEpatents

Golden, Timothy Christoph; Weist, Jr., Edward Landis; Johnson, Charles Henry

2004-03-16

In a process for the production of a polyolefin, an olefin monomer is polymerised said polyolefin and residual monomer is recovered. A gas stream comprising the monomer and nitrogen is subjected to a PSA process in which said monomer is adsorbed on a periodically regenerated silica gel or alumina adsorbent to recover a purified gas stream containing said olefin and a nitrogen rich stream containing no less than 99% nitrogen and containing no less than 50% of the nitrogen content of the gas feed to the PSA process.

Symmetric Stream Cipher using Triple Transposition Key Method and Base64 Algorithm for Security Improvement

NASA Astrophysics Data System (ADS)

Nurdiyanto, Heri; Rahim, Robbi; Wulan, Nur

2017-12-01

Symmetric type cryptography algorithm is known many weaknesses in encryption process compared with asymmetric type algorithm, symmetric stream cipher are algorithm that works on XOR process between plaintext and key, to improve the security of symmetric stream cipher algorithm done improvisation by using Triple Transposition Key which developed from Transposition Cipher and also use Base64 algorithm for encryption ending process, and from experiment the ciphertext that produced good enough and very random.

Material and system for catalytic reduction of nitrogen oxide in an exhaust stream of a combustion process

DOEpatents

Gardner, Timothy J.; Lott, Stephen E.; Lockwood, Steven J.; McLaughlin, Linda I.

1998-01-01

A catalytic material of activated hydrous metal oxide doped with platinum, palladium, or a combination of these, and optionally containing an alkali or alkaline earth metal, that is effective for NO.sub.X reduction in an oxidizing exhaust stream from a combustion process is disclosed. A device for reduction of nitrogen oxides in an exhaust stream, particularly an automotive exhaust stream, the device having a substrate coated with the activated noble-metal doped hydrous metal oxide of the invention is also provided.

Dispersal constraints for stream invertebrates: setting realistic timescales for biodiversity restoration.

PubMed

Parkyn, Stephanie M; Smith, Brian J

2011-09-01

Biodiversity goals are becoming increasingly important in stream restoration. Typical models of stream restoration are based on the assumption that if habitat is restored then species will return and ecological processes will re-establish. However, a range of constraints at different scales can affect restoration success. Much of the research in stream restoration ecology has focused on habitat constraints, namely the in-stream and riparian conditions required to restore biota. Dispersal constraints are also integral to determining the timescales, trajectory and potential endpoints of a restored ecosystem. Dispersal is both a means of organism recolonization of restored sites and a vital ecological process that maintains viable populations. We review knowledge of dispersal pathways and explore the factors influencing stream invertebrate dispersal. From empirical and modeling studies of restoration in warm-temperate zones of New Zealand, we make predictions about the timescales of stream ecological restoration under differing levels of dispersal constraints. This process of constraints identification and timescale prediction is proposed as a practical step for resource managers to prioritize and appropriately monitor restoration sites and highlights that in some instances, natural recolonization and achievement of biodiversity goals may not occur.

Dispersal Constraints for Stream Invertebrates: Setting Realistic Timescales for Biodiversity Restoration

NASA Astrophysics Data System (ADS)

Parkyn, Stephanie M.; Smith, Brian J.

2011-09-01

Biodiversity goals are becoming increasingly important in stream restoration. Typical models of stream restoration are based on the assumption that if habitat is restored then species will return and ecological processes will re-establish. However, a range of constraints at different scales can affect restoration success. Much of the research in stream restoration ecology has focused on habitat constraints, namely the in-stream and riparian conditions required to restore biota. Dispersal constraints are also integral to determining the timescales, trajectory and potential endpoints of a restored ecosystem. Dispersal is both a means of organism recolonization of restored sites and a vital ecological process that maintains viable populations. We review knowledge of dispersal pathways and explore the factors influencing stream invertebrate dispersal. From empirical and modeling studies of restoration in warm-temperate zones of New Zealand, we make predictions about the timescales of stream ecological restoration under differing levels of dispersal constraints. This process of constraints identification and timescale prediction is proposed as a practical step for resource managers to prioritize and appropriately monitor restoration sites and highlights that in some instances, natural recolonization and achievement of biodiversity goals may not occur.

Does Value Stream Mapping affect the structure, process, and outcome quality in care facilities? A systematic review.

PubMed

Nowak, Marina; Pfaff, Holger; Karbach, Ute

2017-08-24

Quality improvement within health and social care facilities is needed and has to be evidence-based and patient-centered. Value Stream Mapping, a method of Lean management, aims to increase the patients' value and quality of care by a visualization and quantification of the care process. The aim of this research is to examine the effectiveness of Value Stream Mapping on structure, process, and outcome quality in care facilities. A systematic review is conducted. PubMed, EBSCOhost, including Business Source Complete, Academic Search Complete, PSYCInfo, PSYNDX, SocINDEX with Full Text, Web of Knowledge, and EMBASE ScienceDirect are searched in February 2016. All peer-reviewed papers evaluating Value Stream Mapping and published in English or German from January 2000 are included. For data synthesis, all study results are categorized into Donabedian's model of structure, process, and outcome quality. To assess and interpret the effectiveness of Value Stream Mapping, the frequencies of the results statistically examined are considered. Of the 903 articles retrieved, 22 studies fulfill the inclusion criteria. Of these, 11 studies are used to answer the research question. Value Stream Mapping has positive effects on the time dimension of process and outcome quality. It seems to reduce non-value-added time (e.g., waiting time) and length of stay. All study designs are before and after studies without control, and methodologically sophisticated studies are missing. For a final conclusion about Value Stream Mapping's effectiveness, more research with improved methodology is needed. Despite this lack of evidence, Value Stream Mapping has the potential to improve quality of care on the time dimension. The contextual influence has to be investigated to make conclusions about the relationship between different quality domains when applying Value Stream Mapping. However, for using this review's conclusion, the limitation of including heterogeneous and potentially biased results has to be considered.

NO.sub.x sensor and process for detecting NO.sub.x

DOEpatents

Dalla Betta, Ralph A.; Sheridan, David R.; Reed, Daniel L.

1994-01-01

This invention is a process for detecting low levels of nitrogen oxides (NO.sub.x) in a flowing gas stream (typically an exhaust gas stream) and a catalytic NO.sub.x sensor which may be used in that process.

Liquid additives for particulate emissions control

DOEpatents

Durham, M.D.; Schlager, R.J.; Ebner, T.G.; Stewart, R.M.; Hyatt, D.E.; Bustard, C.J.; Sjostrom, S.

1999-01-05

The present invention discloses a process for removing undesired particles from a gas stream including the steps of contacting a composition containing an adhesive with the gas stream; collecting the undesired particles and adhesive on a collection surface to form an aggregate comprising the adhesive and undesired particles on the collection surface; and removing the agglomerate from the collection zone. The composition may then be atomized and injected into the gas stream. The composition may include a liquid that vaporizes in the gas stream. After the liquid vaporizes, adhesive particles are entrained in the gas stream. The process may be applied to electrostatic precipitators and filtration systems to improve undesired particle collection efficiency. 11 figs.

Processes for washing a spent ion exchange bed and for treating biomass-derived pyrolysis oil, and apparatuses for treating biomass-derived pyrolysis oil

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baird, Lance Awender; Brandvold, Timothy A.

Processes and apparatuses for washing a spent ion exchange bed and for treating biomass-derived pyrolysis oil are provided herein. An exemplary process for washing a spent ion exchange bed employed in purification of biomass-derived pyrolysis oil includes the step of providing a ion-depleted pyrolysis oil stream having an original oxygen content. The ion-depleted pyrolysis oil stream is partially hydrotreated to reduce the oxygen content thereof, thereby producing a partially hydrotreated pyrolysis oil stream having a residual oxygen content that is less than the original oxygen content. At least a portion of the partially hydrotreated pyrolysis oil stream is passed throughmore » the spent ion exchange bed. Water is passed through the spent ion exchange bed after passing at least the portion of the partially hydrotreated pyrolysis oil stream therethrough.« less

SIMULATION COASTAL PLAIN STREAM FISH COMMUNITY RESPONSE TO NONPOINT SOURCE POLLUTION USING LINKED HYDROLOGIC-ECOLOGICAL MODELS

EPA Science Inventory

Nonpoint source pollution is the primary stress in many streams. Characteristic declines in stream fish communities are recognized in streams influenced by nonpoint source pollution, but the processes by which these declines occur are not well understood. Here, predicted time s...

Face and location processing in children with early unilateral brain injury.

PubMed

Paul, Brianna; Appelbaum, Mark; Carapetian, Stephanie; Hesselink, John; Nass, Ruth; Trauner, Doris; Stiles, Joan

2014-07-01

Human visuospatial functions are commonly divided into those dependent on the ventral visual stream (ventral occipitotemporal regions), which allows for processing the 'what' of an object, and the dorsal visual stream (dorsal occipitoparietal regions), which allows for processing 'where' an object is in space. Information about the development of each of the two streams has been accumulating, but very little is known about the effects of injury, particularly very early injury, on this developmental process. Using a set of computerized dorsal and ventral stream tasks matched for stimuli, required response, and difficulty (for typically-developing individuals), we sought to compare the differential effects of injury to the two systems by examining performance in individuals with perinatal brain injury (PBI), who present with selective deficits in visuospatial processing from a young age. Thirty participants (mean=15.1 years) with early unilateral brain injury (15 right hemisphere PBI, 15 left hemisphere PBI) and 16 matched controls participated. On our tasks children with PBI performed more poorly than controls (lower accuracy and longer response times), and this was particularly prominent for the ventral stream task. Lateralization of PBI was also a factor, as the dorsal stream task did not seem to be associated with lateralized deficits, with both PBI groups showing only subtle decrements in performance, while the ventral stream task elicited deficits from RPBI children that do not appear to improve with age. Our findings suggest that early injury results in lesion-specific visuospatial deficits that persist into adolescence. Further, as the stimuli used in our ventral stream task were faces, our findings are consistent with what is known about the neural systems for face processing, namely, that they are established relatively early, follow a comparatively rapid developmental trajectory (conferring a vulnerability to early insult), and are biased toward the right hemisphere. Copyright © 2014 Elsevier Inc. All rights reserved.

Partial oxidation process for producing a stream of hot purified gas

DOEpatents

Leininger, Thomas F.; Robin, Allen M.; Wolfenbarger, James K.; Suggitt, Robert M.

1995-01-01

A partial oxidation process for the production of a stream of hot clean gas substantially free from particulate matter, ammonia, alkali metal compounds, halides and sulfur-containing gas for use as synthesis gas, reducing gas, or fuel gas. A hydrocarbonaceous fuel comprising a solid carbonaceous fuel with or without liquid hydrocarbonaceous fuel or gaseous hydrocarbon fuel, wherein said hydrocarbonaceous fuel contains halides, alkali metal compounds, sulfur, nitrogen and inorganic ash containing components, is reacted in a gasifier by partial oxidation to produce a hot raw gas stream comprising H.sub.2, CO, CO.sub.2, H.sub.2 O, CH.sub.4, NH.sub.3, HCl, HF, H.sub.2 S, COS, N.sub.2, Ar, particulate matter, vapor phase alkali metal compounds, and molten slag. The hot raw gas stream from the gasifier is split into two streams which are separately deslagged, cleaned and recombined. Ammonia in the gas mixture is catalytically disproportionated into N.sub.2 and H.sub.2. The ammonia-free gas stream is then cooled and halides in the gas stream are reacted with a supplementary alkali metal compound to remove HCl and HF. Alkali metal halides, vaporized alkali metal compounds and residual fine particulate matter are removed from the gas stream by further cooling and filtering. The sulfur-containing gases in the process gas stream are then reacted at high temperature with a regenerable sulfur-reactive mixed metal oxide sulfur sorbent material to produce a sulfided sorbent material which is then separated from the hot clean purified gas stream having a temperature of at least 1000.degree. F.

Partial oxidation process for producing a stream of hot purified gas

DOEpatents

Leininger, T.F.; Robin, A.M.; Wolfenbarger, J.K.; Suggitt, R.M.

1995-03-28

A partial oxidation process is described for the production of a stream of hot clean gas substantially free from particulate matter, ammonia, alkali metal compounds, halides and sulfur-containing gas for use as synthesis gas, reducing gas, or fuel gas. A hydrocarbonaceous fuel comprising a solid carbonaceous fuel with or without liquid hydrocarbonaceous fuel or gaseous hydrocarbon fuel, wherein said hydrocarbonaceous fuel contains halides, alkali metal compounds, sulfur, nitrogen and inorganic ash containing components, is reacted in a gasifier by partial oxidation to produce a hot raw gas stream comprising H{sub 2}, CO, CO{sub 2}, H{sub 2}O, CH{sub 4}, NH{sub 3}, HCl, HF, H{sub 2}S, COS, N{sub 2}, Ar, particulate matter, vapor phase alkali metal compounds, and molten slag. The hot raw gas stream from the gasifier is split into two streams which are separately deslagged, cleaned and recombined. Ammonia in the gas mixture is catalytically disproportionated into N{sub 2} and H{sub 2}. The ammonia-free gas stream is then cooled and halides in the gas stream are reacted with a supplementary alkali metal compound to remove HCl and HF. Alkali metal halides, vaporized alkali metal compounds and residual fine particulate matter are removed from the gas stream by further cooling and filtering. The sulfur-containing gases in the process gas stream are then reacted at high temperature with a regenerable sulfur-reactive mixed metal oxide sulfur sorbent material to produce a sulfided sorbent material which is then separated from the hot clean purified gas stream having a temperature of at least 1000 F. 1 figure.

Sources, transformations, and hydrological processes that control stream nitrate and dissolved organic matter concentrations during snowmelt in an upland forest

Treesearch

Stephen D. Sebestyen; Elizabeth W. Boyer; James B. Shanley; Carol Kendall; Daniel H. Doctor; George R. Aiken; Nobuhito Ohte

2008-01-01

We explored catchment processes that control stream nutrient concentrations at an upland forest in northeastern Vermont, USA, where inputs of nitrogen via atmospheric deposition are among the highest in the nation and affect ecosystem functioning. We traced sources of water, nitrate, and dissolved organic matter (DOM) using stream water samples collected at high...

Electrolytic trapping of iodine from process gas streams

DOEpatents

Horner, Donald E.; Mailen, James C.; Posey, Franz A.

1977-01-25

A method for removing molecular, inorganic, and organic forms of iodine from process gas streams comprises the electrolytic oxidation of iodine in the presence of cobalt-III ions. The gas stream is passed through the anode compartment of a partitioned electrolytic cell having a nitric acid anolyte containing a catalytic amount of cobalt to cause the oxidation of effluent iodine species to aqueous soluble species.

Two Visual Pathways in Primates Based on Sampling of Space: Exploitation and Exploration of Visual Information.

PubMed

Sheth, Bhavin R; Young, Ryan

2016-01-01

Evidence is strong that the visual pathway is segregated into two distinct streams-ventral and dorsal. Two proposals theorize that the pathways are segregated in function: The ventral stream processes information about object identity, whereas the dorsal stream, according to one model, processes information about either object location, and according to another, is responsible in executing movements under visual control. The models are influential; however recent experimental evidence challenges them, e.g., the ventral stream is not solely responsible for object recognition; conversely, its function is not strictly limited to object vision; the dorsal stream is not responsible by itself for spatial vision or visuomotor control; conversely, its function extends beyond vision or visuomotor control. In their place, we suggest a robust dichotomy consisting of a ventral stream selectively sampling high-resolution/ focal spaces, and a dorsal stream sampling nearly all of space with reduced foveal bias. The proposal hews closely to the theme of embodied cognition: Function arises as a consequence of an extant sensory underpinning. A continuous, not sharp, segregation based on function emerges, and carries with it an undercurrent of an exploitation-exploration dichotomy. Under this interpretation, cells of the ventral stream, which individually have more punctate receptive fields that generally include the fovea or parafovea, provide detailed information about object shapes and features and lead to the systematic exploitation of said information; cells of the dorsal stream, which individually have large receptive fields, contribute to visuospatial perception, provide information about the presence/absence of salient objects and their locations for novel exploration and subsequent exploitation by the ventral stream or, under certain conditions, the dorsal stream. We leverage the dichotomy to unify neuropsychological cases under a common umbrella, account for the increased prevalence of multisensory integration in the dorsal stream under a Bayesian framework, predict conditions under which object recognition utilizes the ventral or dorsal stream, and explain why cells of the dorsal stream drive sensorimotor control and motion processing and have poorer feature selectivity. Finally, the model speculates on a dynamic interaction between the two streams that underscores a unified, seamless perception. Existing theories are subsumed under our proposal.

Methods of hydrotreating a liquid stream to remove clogging compounds

DOEpatents

Minderhoud, Johannes Kornelis [Amsterdam, NL; Nelson, Richard Gene [Katy, TX; Roes, Augustinus Wilhelmus Maria [Houston, TX; Ryan, Robert Charles [Houston, TX; Nair, Vijay [Katy, TX

2009-09-22

A method includes producing formation fluid from a subsurface in situ heat treatment process. The formation fluid is separated to produce a liquid stream and a gas stream. At least a portion of the liquid stream is provided to a hydrotreating unit. At least a portion of selected in situ heat treatment clogging compositions in the liquid stream are removed to produce a hydrotreated liquid stream by hydrotreating at least a portion of the liquid stream at conditions sufficient to remove the selected in situ heat treatment clogging compositions.

Perception of shapes targeting local and global processes in autism spectrum disorders.

PubMed

Grinter, Emma J; Maybery, Murray T; Pellicano, Elizabeth; Badcock, Johanna C; Badcock, David R

2010-06-01

Several researchers have found evidence for impaired global processing in the dorsal visual stream in individuals with autism spectrum disorders (ASDs). However, support for a similar pattern of visual processing in the ventral visual stream is less consistent. Critical to resolving the inconsistency is the assessment of local and global form processing ability. Within the visual domain, radial frequency (RF) patterns - shapes formed by sinusoidally varying the radius of a circle to add 'bumps' of a certain number to a circle - can be used to examine local and global form perception. Typically developing children and children with an ASD discriminated between circles and RF patterns that are processed either locally (RF24) or globally (RF3). Children with an ASD required greater shape deformation to identify RF3 shapes compared to typically developing children, consistent with difficulty in global processing in the ventral stream. No group difference was observed for RF24 shapes, suggesting intact local ventral-stream processing. These outcomes support the position that a deficit in global visual processing is present in ASDs, consistent with the notion of Weak Central Coherence.

Ambient groundwater flow diminishes nitrate processing in the hyporheic zone of streams

NASA Astrophysics Data System (ADS)

Azizian, Morvarid; Boano, Fulvio; Cook, Perran L. M.; Detwiler, Russell L.; Rippy, Megan A.; Grant, Stanley B.

2017-05-01

Modeling and experimental studies demonstrate that ambient groundwater reduces hyporheic exchange, but the implications of this observation for stream N-cycling is not yet clear. Here we utilize a simple process-based model (the Pumping and Streamline Segregation or PASS model) to evaluate N-cycling over two scales of hyporheic exchange (fluvial ripples and riffle-pool sequences), ten ambient groundwater and stream flow scenarios (five gaining and losing conditions and two stream discharges), and three biogeochemical settings (identified based on a principal component analysis of previously published measurements in streams throughout the United States). Model-data comparisons indicate that our model provides realistic estimates for direct denitrification of stream nitrate, but overpredicts nitrification and coupled nitrification-denitrification. Riffle-pool sequences are responsible for most of the N-processing, despite the fact that fluvial ripples generate 3-11 times more hyporheic exchange flux. Across all scenarios, hyporheic exchange flux and the Damköhler Number emerge as primary controls on stream N-cycling; the former regulates trafficking of nutrients and oxygen across the sediment-water interface, while the latter quantifies the relative rates of organic carbon mineralization and advective transport in streambed sediments. Vertical groundwater flux modulates both of these master variables in ways that tend to diminish stream N-cycling. Thus, anthropogenic perturbations of ambient groundwater flows (e.g., by urbanization, agricultural activities, groundwater mining, and/or climate change) may compromise some of the key ecosystem services provided by streams.

Tracer-based characterization of hyporheic exchange and benthic biolayers in streams

NASA Astrophysics Data System (ADS)

Knapp, Julia L. A.; González-Pinzón, Ricardo; Drummond, Jennifer D.; Larsen, Laurel G.; Cirpka, Olaf A.; Harvey, Judson W.

2017-02-01

Shallow benthic biolayers at the top of the streambed are believed to be places of enhanced biogeochemical turnover within the hyporheic zone. They can be investigated by reactive stream tracer tests with tracer recordings in the streambed and in the stream channel. Common in-stream measurements of such reactive tracers cannot localize where the processing primarily takes place, whereas isolated vertical depth profiles of solutes within the hyporheic zone are usually not representative of the entire stream. We present results of a tracer test where we injected the conservative tracer bromide together with the reactive tracer resazurin into a third-order stream and combined the recording of in-stream breakthrough curves with multidepth sampling of the hyporheic zone at several locations. The transformation of resazurin was used as an indicator of metabolism, and high-reactivity zones were identified from depth profiles. The results from our subsurface analysis indicate that the potential for tracer transformation (i.e., the reaction rate constant) varied with depth in the hyporheic zone. This highlights the importance of the benthic biolayer, which we found to be on average 2 cm thick in this study, ranging from one third to one half of the full depth of the hyporheic zone. The reach-scale approach integrated the effects of processes along the reach length, isolating hyporheic processes relevant for whole-stream chemistry and estimating effective reaction rates.

Tracer-based characterization of hyporheic exchange and benthic biolayers in streams

USGS Publications Warehouse

Knapp, Julia L.A.; González-Pinzón, Ricardo; Drummond, Jennifer D.; Larsen, Laurel G.; Cirpka, Olaf A.; Harvey, Judson W.

2017-01-01

Shallow benthic biolayers at the top of the streambed are believed to be places of enhanced biogeochemical turnover within the hyporheic zone. They can be investigated by reactive stream tracer tests with tracer recordings in the streambed and in the stream channel. Common in-stream measurements of such reactive tracers cannot localize where the processing primarily takes place, whereas isolated vertical depth profiles of solutes within the hyporheic zone are usually not representative of the entire stream. We present results of a tracer test where we injected the conservative tracer bromide together with the reactive tracer resazurin into a third-order stream and combined the recording of in-stream breakthrough curves with multidepth sampling of the hyporheic zone at several locations. The transformation of resazurin was used as an indicator of metabolism, and high-reactivity zones were identified from depth profiles. The results from our subsurface analysis indicate that the potential for tracer transformation (i.e., the reaction rate constant) varied with depth in the hyporheic zone. This highlights the importance of the benthic biolayer, which we found to be on average 2 cm thick in this study, ranging from one third to one half of the full depth of the hyporheic zone. The reach-scale approach integrated the effects of processes along the reach length, isolating hyporheic processes relevant for whole-stream chemistry and estimating effective reaction rates.

Adaptations to vision-for-action in primate brain evolution: Comment on "Towards a Computational Comparative Neuroprimatology: Framing the language-ready brain" by Michael A. Arbib

NASA Astrophysics Data System (ADS)

Hecht, Erin

2016-03-01

As Arbib [1] notes, the two-streams hypothesis [5] has provided a powerful explanatory framework for understanding visual processing. The inferotemporal ventral stream recognizes objects and agents - ;what; one is seeing. The dorsal ;how; or ;where; stream through parietal cortex processes motion, spatial location, and visuo-proprioceptive relationships - ;vision for action.; Hickock and Poeppel's [3] extension of this model to the auditory system raises the question of deeper, multi- or supra-sensory themes in dorsal vs. ventral processing. Petrides and Pandya [10] postulate that the evolution of language may have been influenced by the fact that the dorsal stream terminates in posterior Broca's area (BA44) while the ventral stream terminates in anterior Broca's area (BA45). In an intriguing potential parallel, a recent ALE metanalysis of 54 fMRI studies found that semantic processing is located more anteriorly and superiorly than syntactic processing in Broca's area [13]. But clearly, macaques do not have language, nor other likely pre- or co-adaptations to language, such as complex imitation and tool use. What changed in the brain that enabled these functions to evolve?

New methods for modeling stream temperature using high resolution LiDAR, solar radiation analysis and flow accumulated values to predict stream temperature

EPA Science Inventory

In-stream temperature directly effects a variety of biotic organisms, communities and processes. Changes in stream temperature can render formally suitable habitat unsuitable for aquatic organisms, particularly native cold water species that are not able to adjust. In order to...

Radar meteor orbital structure of Southern Hemisphere cometary dust streams

NASA Technical Reports Server (NTRS)

Baggaley, W. Jack; Taylor, Andrew D.

1992-01-01

The Christchurch, New Zealand meteor orbit radar (AMOR) with its high precision and sensitivity, permits studies of the orbital fine structure of cometary streams. PC generated graphics are presented of data on some Southern Hemisphere Streams. Such data can be related to the formation phase and subsequent dynamical processes of dust streams.

An evaluation of underwater epoxies to permanently install temperature sensors in mountain streams

Treesearch

Daniel J. Isaak; Dona L. Horan

2011-01-01

Stream temperature regimes are of fundamental importance in understanding the patterns and processes in aquatic ecosystems, and inexpensive digital sensors provide accurate and repeated measurements of temperature. Most temperature measurements in mountain streams are made only during summer months because of logistical constraints associated with stream access and...

Use of once-through treat gas to remove the heat of reaction in solvent hydrogenation processes

DOEpatents

Nizamoff, Alan J.

1980-01-01

In a coal liquefaction process wherein feed coal is contacted with molecular hydrogen and a hydrogen-donor solvent in a liquefaction zone to form coal liquids and vapors and coal liquids in the solvent boiling range are thereafter hydrogenated to produce recycle solvent and liquid products, the improvement which comprises separating the effluent from the liquefaction zone into a hot vapor stream and a liquid stream; cooling the entire hot vapor stream sufficiently to condense vaporized liquid hydrocarbons; separating condensed liquid hydrocarbons from the cooled vapor; fractionating the liquid stream to produce coal liquids in the solvent boiling range; dividing the cooled vapor into at least two streams; passing the cooling vapors from one of the streams, the coal liquids in the solvent boiling range, and makeup hydrogen to a solvent hydrogenation zone, catalytically hydrogenating the coal liquids in the solvent boiling range and quenching the hydrogenation zone with cooled vapors from the other cooled vapor stream.

Modeling the economics of landfilling organic processing waste streams

NASA Astrophysics Data System (ADS)

Rosentrater, Kurt A.

2005-11-01

As manufacturing industries become more cognizant of the ecological effects that their firms have on the surrounding environment, their waste streams are increasingly becoming viewed not only as materials in need of disposal, but also as resources that can be reused, recycled, or reprocessed into valuable products. Within the food processing sector are many examples of various liquid, sludge, and solid biological and organic waste streams that require remediation. Alternative disposal methods for food and other bio-organic manufacturing waste streams are increasingly being investigated. Direct shipping, blending, extrusion, pelleting, and drying are commonly used to produce finished human food, animal feed, industrial products, and components ready for further manufacture. Landfilling, the traditional approach to waste remediation, however, should not be dismissed entirely. It does provide a baseline to which all other recycling and reprocessing options should be compared. This paper discusses the implementation of a computer model designed to examine the economics of landfilling bio-organic processing waste streams. Not only are these results applicable to food processing operations, but any industrial or manufacturing firm would benefit from examining the trends discussed here.

Electrodialysis-based separation process for salt recovery and recycling from waste water

DOEpatents

Tsai, S.P.

1997-07-08

A method for recovering salt from a process stream containing organic contaminants is provided, comprising directing the waste stream to a desalting electrodialysis unit so as to create a concentrated and purified salt permeate and an organic contaminants-containing stream, and contacting said concentrated salt permeate to a water-splitting electrodialysis unit so as to convert the salt to its corresponding base and acid. 6 figs.

Electrodialysis-based separation process for salt recovery and recycling from waste water

DOEpatents

Tsai, Shih-Perng

1997-01-01

A method for recovering salt from a process stream containing organic contaminants is provided, comprising directing the waste stream to a desalting electrodialysis unit so as to create a concentrated and purified salt permeate and an organic contaminants containing stream, and contacting said concentrated salt permeate to a water-splitting electrodialysis unit so as to convert the salt to its corresponding base and acid.

Spatial and temporal patterns of stream burial and its effect on habitat connectivity across headwater stream communities of the Potomac River Basin, USA

NASA Astrophysics Data System (ADS)

Weitzell, R.; Guinn, S. M.; Elmore, A. J.

2012-12-01

The process of directing streams into culverts, pipes, or concrete-lined ditches during urbanization, known as stream burial, alters the primary physical, chemical, and biological processes of streams. Knowledge of the cumulative impacts of reduced structure and ecological function within buried stream networks is crucial for informing management of stream ecosystems, in light of continued growth in urban areas, and the uncertain response of freshwater ecosystems to the stresses of global climate change. To address this need, we utilized recently improved stream maps for the Potomac River Basin (PRB) to describe the extent and severity of stream burial across the basin. Observations of stream burial made from high resolution aerial photographs (>1% of total basin area) and a decision tree using spatial statistics from impervious cover data were used to predict stream burial at 4 time-steps (1975, 1990, 2001, 2006). Of the roughly 95,500 kilometers (km) of stream in the PRB, approximately 4551 km (4.76%) were buried by urban development as of 2001. Analysis of county-level burial trends shows differential patterns in the timing and rates of headwater stream burial, which may be due to local development policies, topographical constraints, and/or time since development. Consistently higher rates of stream burial were observed for small streams, decreasing with stream order. Headwater streams (1st-2nd order) are disproportionately affected, with burial rates continuing to increase over time in relation to larger stream orders. Beyond simple habitat loss, headwater burial decreases connectivity among headwater populations and habitats, with potential to affect a wide range of important ecological processes. To quantify changes to regional headwater connectivity we applied a connectivity model based on electrical circuit theory. Circuit-theoretical models function by treating the landscape as a resistance surface, representing hypothesized relationships between landscape features and their differential "resistance" to movement by organisms. A landscape resistance layer was developed and fine-tuned in terms of the habitat use/needs of aquatic invertebrates with terrestrial adult stages, organisms of critical importance to riparian and aquatic ecosystem health. Initial results show significant increases in landscape resistance (isolation) among headwater systems, and corresponding decreases in current flow (movement of organisms) across the increasingly urbanized PRB landscape. Of particular interest, the circuit model highlighted the importance of stream confluences and zero-order (non-channel) headwater areas for movement of organisms between headwater systems that are otherwise highly disconnected, and for which the latter currently receives no legal protection from development.

Method and apparatus for combination catalyst for reduction of NO.sub.x in combustion products

DOEpatents

Socha, Richard F.; Vartuli, James C.; El-Malki, El-Mekki; Kalyanaraman, Mohan; Park, Paul W.

2010-09-28

A method and apparatus for catalytically processing a gas stream passing therethrough to reduce the presence of NO.sub.x therein, wherein the apparatus includes a first catalyst composed of a silver containing alumina that is adapted for catalytically processing the gas stream at a first temperature range, and a second catalyst composed of a copper containing zeolite located downstream from the first catalyst, wherein the second catalyst is adapted for catalytically processing the gas stream at a lower second temperature range relative to the first temperature range.

Gas separation process using membranes with permeate sweep to remove CO.sub.2 from gaseous fuel combustion exhaust

DOEpatents

Wijmans, Johannes G [Menlo Park, CA; Merkel, Timothy C [Menlo Park, CA; Baker, Richard W [Palo Alto, CA

2012-05-15

A gas separation process for treating exhaust gases from the combustion of gaseous fuels, and gaseous fuel combustion processes including such gas separation. The invention involves routing a first portion of the exhaust stream to a carbon dioxide capture step, while simultaneously flowing a second portion of the exhaust gas stream across the feed side of a membrane, flowing a sweep gas stream, usually air, across the permeate side, then passing the permeate/sweep gas back to the combustor.

Combining multiple approaches and optimized data resolution for an improved understanding of stream temperature dynamics of a forested headwater basin in the Southern Appalachians

NASA Astrophysics Data System (ADS)

Belica, L.; Mitasova, H.; Caldwell, P.; McCarter, J. B.; Nelson, S. A. C.

2017-12-01

Thermal regimes of forested headwater streams continue to be an area of active research as climatic, hydrologic, and land cover changes can influence water temperature, a key aspect of aquatic ecosystems. Widespread monitoring of stream temperatures have provided an important data source, yielding insights on the temporal and spatial patterns and the underlying processes that influence stream temperature. However, small forested streams remain challenging to model due to the high spatial and temporal variability of stream temperatures and the climatic and hydrologic conditions that drive them. Technological advances and increased computational power continue to provide new tools and measurement methods and have allowed spatially explicit analyses of dynamic natural systems at greater temporal resolutions than previously possible. With the goal of understanding how current stream temperature patterns and processes may respond to changing landcover and hydroclimatoligical conditions, we combined high-resolution, spatially explicit geospatial modeling with deterministic heat flux modeling approaches using data sources that ranged from traditional hydrological and climatological measurements to emerging remote sensing techniques. Initial analyses of stream temperature monitoring data revealed that high temporal resolution (5 minutes) and measurement resolutions (<0.1°C) were needed to adequately describe diel stream temperature patterns and capture the differences between paired 1st order and 4th order forest streams draining north and south facing slopes. This finding along with geospatial models of subcanopy solar radiation and channel morphology were used to develop hypotheses and guide field data collection for further heat flux modeling. By integrating multiple approaches and optimizing data resolution for the processes being investigated, small, but ecologically significant differences in stream thermal regimes were revealed. In this case, multi-approach research contributed to the identification of the dominant mechanisms driving stream temperature in the study area and advanced our understanding of the current thermal fluxes and how they may change as environmental conditions change in the future.

Methods of making transportation fuel

DOEpatents

Roes, Augustinus Wilhelmus Maria [Houston, TX; Mo, Weijian [Sugar Land, TX; Muylle, Michel Serge Marie [Houston, TX; Mandema, Remco Hugo [Houston, TX; Nair, Vijay [Katy, TX

2012-04-10

A method for producing alkylated hydrocarbons is disclosed. Formation fluid is produced from a subsurface in situ heat treatment process. The formation fluid is separated to produce a liquid stream and a first gas stream. The first gas stream includes olefins. The liquid stream is fractionated to produce at least a second gas stream including hydrocarbons having a carbon number of at least 3. The first gas stream and the second gas stream are introduced into an alkylation unit to produce alkylated hydrocarbons. At least a portion of the olefins in the first gas stream enhance alkylation. The alkylated hydrocarbons may be blended with one or more components to produce transportation fuel.

Dual-stream accounts bridge the gap between monkey audition and human language processing. Comment on "Towards a Computational Comparative Neuroprimatology: Framing the language-ready brain" by Michael Arbib

NASA Astrophysics Data System (ADS)

Garrod, Simon; Pickering, Martin J.

2016-03-01

Over the last few years there has been a resurgence of interest in dual-stream dorsal-ventral accounts of language processing [4]. This has led to recent attempts to bridge the gap between the neurobiology of primate audition and human language processing with the dorsal auditory stream assumed to underlie time-dependent (and syntactic) processing and the ventral to underlie some form of time-independent (and semantic) analysis of the auditory input [3,10]. Michael Arbib [1] considers these developments in relation to his earlier Mirror System Hypothesis about the origins of human language processing [11].

On the patterns and processes of wood in northern California streams

NASA Astrophysics Data System (ADS)

Benda, Lee; Bigelow, Paul

2014-03-01

Forest management and stream habitat can be improved by clarifying the primary riparian and geomorphic controls on streams. To this end, we evaluated the recruitment, storage, transport, and the function of wood in 95 km of streams (most drainage areas < 30 km2) in northern California, crossing four coastal to inland regions with different histories of forest management (managed, less-managed, unmanaged). The dominant source of variability in stream wood storage and recruitment is driven by local variation in rates of bank erosion, forest mortality, and mass wasting. These processes are controlled by changes in watershed structure, including the location of canyons, floodplains and tributary confluences; types of geology and topography; and forest types and management history. Average wood storage volumes in coastal streams are 5 to 20 times greater than inland sites primarily from higher riparian forest biomass and growth rates (productivity), with some influence by longer residence time of wood in streams and more wood from landsliding and logging sources. Wood recruitment by mortality (windthrow, disease, senescence) was substantial across all sites (mean 50%) followed by bank erosion (43%) and more locally by mass wasting (7%). The distances to sources of stream wood are controlled by recruitment process and tree height. Ninety percent of wood recruitment occurs within 10 to 35 m of channels in managed and less-managed forests and upward of 50 m in unmanaged Sequoia and coast redwood forests. Local landsliding extends the source distance. The recruitment of large wood pieces that create jams (mean diameter 0.7 m) is primarily by bank erosion in managed forests and by mortality in unmanaged forests. Formation of pools by wood is more frequent in streams with low stream power, indicating the further relevance of environmental context and watershed structure. Forest management influences stream wood dynamics, where smaller trees in managed forests often generate shorter distances to sources of stream wood, lower stream wood storage, and smaller diameter stream wood. These findings can be used to improve riparian protection and inform spatially explicit riparian management.

Two Visual Pathways in Primates Based on Sampling of Space: Exploitation and Exploration of Visual Information

PubMed Central

Sheth, Bhavin R.; Young, Ryan

2016-01-01

Evidence is strong that the visual pathway is segregated into two distinct streams—ventral and dorsal. Two proposals theorize that the pathways are segregated in function: The ventral stream processes information about object identity, whereas the dorsal stream, according to one model, processes information about either object location, and according to another, is responsible in executing movements under visual control. The models are influential; however recent experimental evidence challenges them, e.g., the ventral stream is not solely responsible for object recognition; conversely, its function is not strictly limited to object vision; the dorsal stream is not responsible by itself for spatial vision or visuomotor control; conversely, its function extends beyond vision or visuomotor control. In their place, we suggest a robust dichotomy consisting of a ventral stream selectively sampling high-resolution/focal spaces, and a dorsal stream sampling nearly all of space with reduced foveal bias. The proposal hews closely to the theme of embodied cognition: Function arises as a consequence of an extant sensory underpinning. A continuous, not sharp, segregation based on function emerges, and carries with it an undercurrent of an exploitation-exploration dichotomy. Under this interpretation, cells of the ventral stream, which individually have more punctate receptive fields that generally include the fovea or parafovea, provide detailed information about object shapes and features and lead to the systematic exploitation of said information; cells of the dorsal stream, which individually have large receptive fields, contribute to visuospatial perception, provide information about the presence/absence of salient objects and their locations for novel exploration and subsequent exploitation by the ventral stream or, under certain conditions, the dorsal stream. We leverage the dichotomy to unify neuropsychological cases under a common umbrella, account for the increased prevalence of multisensory integration in the dorsal stream under a Bayesian framework, predict conditions under which object recognition utilizes the ventral or dorsal stream, and explain why cells of the dorsal stream drive sensorimotor control and motion processing and have poorer feature selectivity. Finally, the model speculates on a dynamic interaction between the two streams that underscores a unified, seamless perception. Existing theories are subsumed under our proposal. PMID:27920670

Quantifying spatial differences in metabolism in headwater streams

Treesearch

Ricardo González-Pinzón; Roy Haggerty; Alba Argerich

2014-01-01

Stream functioning includes simultaneous interaction among solute transport, nutrient processing, and metabolism. Metabolism is measured with methods that have limited spatial representativeness and are highly uncertain. These problems restrict development of methods for up-scaling biological processes that mediate nutrient processing. We used the resazurin–resorufin (...

Mass, energy and material balances of SRF production process. Part 3: solid recovered fuel produced from municipal solid waste.

PubMed

Nasrullah, Muhammad; Vainikka, Pasi; Hannula, Janne; Hurme, Markku; Kärki, Janne

2015-02-01

This is the third and final part of the three-part article written to describe the mass, energy and material balances of the solid recovered fuel production process produced from various types of waste streams through mechanical treatment. This article focused the production of solid recovered fuel from municipal solid waste. The stream of municipal solid waste used here as an input waste material to produce solid recovered fuel is energy waste collected from households of municipality. This article presents the mass, energy and material balances of the solid recovered fuel production process. These balances are based on the proximate as well as the ultimate analysis and the composition determination of various streams of material produced in a solid recovered fuel production plant. All the process streams are sampled and treated according to CEN standard methods for solid recovered fuel. The results of the mass balance of the solid recovered fuel production process showed that 72% of the input waste material was recovered in the form of solid recovered fuel; 2.6% as ferrous metal, 0.4% as non-ferrous metal, 11% was sorted as rejects material, 12% as fine faction and 2% as heavy fraction. The energy balance of the solid recovered fuel production process showed that 86% of the total input energy content of input waste material was recovered in the form of solid recovered fuel. The remaining percentage (14%) of the input energy was split into the streams of reject material, fine fraction and heavy fraction. The material balances of this process showed that mass fraction of paper and cardboard, plastic (soft) and wood recovered in the solid recovered fuel stream was 88%, 85% and 90%, respectively, of their input mass. A high mass fraction of rubber material, plastic (PVC-plastic) and inert (stone/rock and glass particles) was found in the reject material stream. © The Author(s) 2014.

Differential modulation of visual object processing in dorsal and ventral stream by stimulus visibility.

PubMed

Ludwig, Karin; Sterzer, Philipp; Kathmann, Norbert; Hesselmann, Guido

2016-10-01

As a functional organization principle in cortical visual information processing, the influential 'two visual systems' hypothesis proposes a division of labor between a dorsal "vision-for-action" and a ventral "vision-for-perception" stream. A core assumption of this model is that the two visual streams are differentially involved in visual awareness: ventral stream processing is closely linked to awareness while dorsal stream processing is not. In this functional magnetic resonance imaging (fMRI) study with human observers, we directly probed the stimulus-related information encoded in fMRI response patterns in both visual streams as a function of stimulus visibility. We parametrically modulated the visibility of face and tool stimuli by varying the contrasts of the masks in a continuous flash suppression (CFS) paradigm. We found that visibility - operationalized by objective and subjective measures - decreased proportionally with increasing log CFS mask contrast. Neuronally, this relationship was closely matched by ventral visual areas, showing a linear decrease of stimulus-related information with increasing mask contrast. Stimulus-related information in dorsal areas also showed a dependency on mask contrast, but the decrease rather followed a step function instead of a linear function. Together, our results suggest that both the ventral and the dorsal visual stream are linked to visual awareness, but neural activity in ventral areas more closely reflects graded differences in awareness compared to dorsal areas. Copyright © 2016 Elsevier Ltd. All rights reserved.

Endogenous Delta/Theta Sound-Brain Phase Entrainment Accelerates the Buildup of Auditory Streaming.

PubMed

Riecke, Lars; Sack, Alexander T; Schroeder, Charles E

2015-12-21

In many natural listening situations, meaningful sounds (e.g., speech) fluctuate in slow rhythms among other sounds. When a slow rhythmic auditory stream is selectively attended, endogenous delta (1‒4 Hz) oscillations in auditory cortex may shift their timing so that higher-excitability neuronal phases become aligned with salient events in that stream [1, 2]. As a consequence of this stream-brain phase entrainment [3], these events are processed and perceived more readily than temporally non-overlapping events [4-11], essentially enhancing the neural segregation between the attended stream and temporally noncoherent streams [12]. Stream-brain phase entrainment is robust to acoustic interference [13-20] provided that target stream-evoked rhythmic activity can be segregated from noncoherent activity evoked by other sounds [21], a process that usually builds up over time [22-27]. However, it has remained unclear whether stream-brain phase entrainment functionally contributes to this buildup of rhythmic streams or whether it is merely an epiphenomenon of it. Here, we addressed this issue directly by experimentally manipulating endogenous stream-brain phase entrainment in human auditory cortex with non-invasive transcranial alternating current stimulation (TACS) [28-30]. We assessed the consequences of these manipulations on the perceptual buildup of the target stream (the time required to recognize its presence in a noisy background), using behavioral measures in 20 healthy listeners performing a naturalistic listening task. Experimentally induced cyclic 4-Hz variations in stream-brain phase entrainment reliably caused a cyclic 4-Hz pattern in perceptual buildup time. Our findings demonstrate that strong endogenous delta/theta stream-brain phase entrainment accelerates the perceptual emergence of task-relevant rhythmic streams in noisy environments. Copyright © 2015 Elsevier Ltd. All rights reserved.

Digital Multicasting of Multiple Audio Streams

NASA Technical Reports Server (NTRS)

Macha, Mitchell; Bullock, John

2007-01-01

The Mission Control Center Voice Over Internet Protocol (MCC VOIP) system (see figure) comprises hardware and software that effect simultaneous, nearly real-time transmission of as many as 14 different audio streams to authorized listeners via the MCC intranet and/or the Internet. The original version of the MCC VOIP system was conceived to enable flight-support personnel located in offices outside a spacecraft mission control center to monitor audio loops within the mission control center. Different versions of the MCC VOIP system could be used for a variety of public and commercial purposes - for example, to enable members of the general public to monitor one or more NASA audio streams through their home computers, to enable air-traffic supervisors to monitor communication between airline pilots and air-traffic controllers in training, and to monitor conferences among brokers in a stock exchange. At the transmitting end, the audio-distribution process begins with feeding the audio signals to analog-to-digital converters. The resulting digital streams are sent through the MCC intranet, using a user datagram protocol (UDP), to a server that converts them to encrypted data packets. The encrypted data packets are then routed to the personal computers of authorized users by use of multicasting techniques. The total data-processing load on the portion of the system upstream of and including the encryption server is the total load imposed by all of the audio streams being encoded, regardless of the number of the listeners or the number of streams being monitored concurrently by the listeners. The personal computer of a user authorized to listen is equipped with special- purpose MCC audio-player software. When the user launches the program, the user is prompted to provide identification and a password. In one of two access- control provisions, the program is hard-coded to validate the user s identity and password against a list maintained on a domain-controller computer at the MCC. In the other access-control provision, the program verifies that the user is authorized to have access to the audio streams. Once both access-control checks are completed, the audio software presents a graphical display that includes audiostream-selection buttons and volume-control sliders. The user can select all or any subset of the available audio streams and can adjust the volume of each stream independently of that of the other streams. The audio-player program spawns a "read" process for the selected stream(s). The spawned process sends, to the router(s), a "multicast-join" request for the selected streams. The router(s) responds to the request by sending the encrypted multicast packets to the spawned process. The spawned process receives the encrypted multicast packets and sends a decryption packet to audio-driver software. As the volume or muting features are changed by the user, interrupts are sent to the spawned process to change the corresponding attributes sent to the audio-driver software. The total latency of this system - that is, the total time from the origination of the audio signals to generation of sound at a listener s computer - lies between four and six seconds.

FireHose Streaming Benchmarks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karl Anderson, Steve Plimpton

2015-01-27

The FireHose Streaming Benchmarks are a suite of stream-processing benchmarks defined to enable comparison of streaming software and hardware, both quantitatively vis-a-vis the rate at which they can process data, and qualitatively by judging the effort involved to implement and run the benchmarks. Each benchmark has two parts. The first is a generator which produces and outputs datums at a high rate in a specific format. The second is an analytic which reads the stream of datums and is required to perform a well-defined calculation on the collection of datums, typically to find anomalous datums that have been created inmore » the stream by the generator. The FireHose suite provides code for the generators, sample code for the analytics (which users are free to re-implement in their own custom frameworks), and a precise definition of each benchmark calculation.« less

W-007H B Plant Process Condensate Treatment Facility. Revision 3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rippy, G.L.

1995-01-20

B Plant Process Condensate (BCP) liquid effluent stream is the condensed vapors originating from the operation of the B Plant low-level liquid waste concentration system. In the past, the BCP stream was discharged into the soil column under a compliance plan which expired January 1, 1987. Currently, the BCP stream is inactive, awaiting restart of the E-23-3 Concentrator. B Plant Steam Condensate (BCS) liquid effluent stream is the spent steam condensate used to supply heat to the E-23-3 Concentrator. The tube bundles in the E-23-3 Concentrator discharge to the BCS. In the past, the BCS stream was discharged into themore » soil column. Currently, the BCS stream is inactive. This project shall provide liquid effluent systems (BCP/BCS/BCE) capable of operating for a minimum of 20 years, which does not include the anticipated decontamination and decommissioning (D and D) period.« less

How visual illusions illuminate complementary brain processes: illusory depth from brightness and apparent motion of illusory contours

PubMed Central

Grossberg, Stephen

2014-01-01

Neural models of perception clarify how visual illusions arise from adaptive neural processes. Illusions also provide important insights into how adaptive neural processes work. This article focuses on two illusions that illustrate a fundamental property of global brain organization; namely, that advanced brains are organized into parallel cortical processing streams with computationally complementary properties. That is, in order to process certain combinations of properties, each cortical stream cannot process complementary properties. Interactions between these streams, across multiple processing stages, overcome their complementary deficiencies to compute effective representations of the world, and to thereby achieve the property of complementary consistency. The two illusions concern how illusory depth can vary with brightness, and how apparent motion of illusory contours can occur. Illusory depth from brightness arises from the complementary properties of boundary and surface processes, notably boundary completion and surface-filling in, within the parvocellular form processing cortical stream. This illusion depends upon how surface contour signals from the V2 thin stripes to the V2 interstripes ensure complementary consistency of a unified boundary/surface percept. Apparent motion of illusory contours arises from the complementary properties of form and motion processes across the parvocellular and magnocellular cortical processing streams. This illusion depends upon how illusory contours help to complete boundary representations for object recognition, how apparent motion signals can help to form continuous trajectories for target tracking and prediction, and how formotion interactions from V2-to-MT enable completed object representations to be continuously tracked even when they move behind intermittently occluding objects through time. PMID:25389399

Combined effects of hydrologic alteration and cyprinid fish in mediating biogeochemical processes in a Mediterranean stream.

PubMed

Rubio-Gracia, Francesc; Almeida, David; Bonet, Berta; Casals, Frederic; Espinosa, Carmen; Flecker, Alexander S; García-Berthou, Emili; Martí, Eugènia; Tuulaikhuu, Baigal-Amar; Vila-Gispert, Anna; Zamora, Lluis; Guasch, Helena

2017-12-01

Flow regimes are important drivers of both stream community and biogeochemical processes. However, the interplay between community and biogeochemical responses under different flow regimes in streams is less understood. In this study, we investigated the structural and functional responses of periphyton and macroinvertebrates to different densities of the Mediterranean barbel (Barbus meridionalis, Cyprinidae) in two stream reaches differing in flow regime. The study was conducted in Llémena Stream, a small calcareous Mediterranean stream with high nutrient levels. We selected a reach with permanent flow (permanent reach) and another subjected to flow regulation (regulated reach) with periods of flow intermittency. At each reach, we used in situ cages to generate 3 levels of fish density. Cages with 10 barbels were used to simulate high fish density (>7indm -2 ); cages with open sides were used as controls (i.e. exposed to actual fish densities of each stream reach) thus having low fish density; and those with no fish were used to simulate the disappearance of fish that occurs with stream drying. Differences in fish density did not cause significant changes in periphyton biomass and macroinvertebrate density. However, phosphate uptake by periphyton was enhanced in treatments lacking fish in the regulated reach with intermittent flow but not in the permanent reach, suggesting that hydrologic alteration hampers the ability of biotic communities to compensate for the absence of fish. This study indicates that fish density can mediate the effects of anthropogenic alterations such as flow intermittence derived from hydrologic regulation on stream benthic communities and associated biogeochemical processes, at least in eutrophic streams. Copyright © 2017. Published by Elsevier B.V.

Process for simultaneous removal of SO.sub.2 and NO.sub.x from gas streams

DOEpatents

Rosenberg, Harvey S.

1987-01-01

A process for simultaneous removal of SO.sub.2 and NO.sub.x from a gas stream that includes flowing the gas stream to a spray dryer and absorbing a portion of the SO.sub.2 content of the gas stream and a portion of the NO.sub.x content of the gas stream with ZnO by contacting the gas stream with a spray of an aqueous ZnO slurry; controlling the gas outlet temperature of the spray dryer to within the range of about a 0.degree. to 125.degree. F. approach to the adiabatic saturation temperature; flowing the gas, unreacted ZnO and absorbed SO.sub.2 and NO.sub.x from the spray dryer to a fabric filter and collecting any solids therein and absorbing a portion of the SO.sub.2 remaining in the gas stream and a portion of the NO.sub.x remaining in the gas stream with ZnO; and controlling the ZnO content of the aqueous slurry so that sufficient unreacted ZnO is present in the solids collected in the fabric filter to react with SO.sub.2 and NO.sub.x as the gas passes through the fabric filter whereby the overall feed ratio of ZnO to SO.sub.2 plus NO.sub.x is about 1.0 to 4.0 moles of ZnO per of SO.sub.2 and about 0.5 to 2.0 moles of ZnO per mole of NO.sub.x. Particulates may be removed from the gas stream prior to treatment in the spray dryer. The process further allows regeneration of ZnO that has reacted to absorb SO.sub.2 and NO.sub.x from the gas stream and acid recovery.

Process for simultaneous removal of SO[sub 2] and NO[sub x] from gas streams

DOEpatents

Rosenberg, H.S.

1987-02-03

A process is described for simultaneous removal of SO[sub 2] and NO[sub x] from a gas stream that includes flowing the gas stream to a spray dryer and absorbing a portion of the SO[sub 2] content of the gas stream and a portion of the NO[sub x] content of the gas stream with ZnO by contacting the gas stream with a spray of an aqueous ZnO slurry; controlling the gas outlet temperature of the spray dryer to within the range of about a 0 to 125 F approach to the adiabatic saturation temperature; flowing the gas, unreacted ZnO and absorbed SO[sub 2] and NO[sub x] from the spray dryer to a fabric filter and collecting any solids therein and absorbing a portion of the SO[sub 2] remaining in the gas stream and a portion of the NO[sub x] remaining in the gas stream with ZnO; and controlling the ZnO content of the aqueous slurry so that sufficient unreacted ZnO is present in the solids collected in the fabric filter to react with SO[sub 2] and NO[sub x] as the gas passes through the fabric filter whereby the overall feed ratio of ZnO to SO[sub 2] plus NO[sub x] is about 1.0 to 4.0 moles of ZnO per of SO[sub 2] and about 0.5 to 2.0 moles of ZnO per mole of NO[sub x]. Particulates may be removed from the gas stream prior to treatment in the spray dryer. The process further allows regeneration of ZnO that has reacted to absorb SO[sub 2] and NO[sub x] from the gas stream and acid recovery. 4 figs.

Carbon limitation patterns in buried and open urban streams

EPA Science Inventory

Urban streams alternate between darkened buried segments dominated by heterotrophic processes and lighted open segments dominated by autotrophic processes. We hypothesized that labile carbon leaking from autotrophic cells would reduce heterotrophic carbon limitation in open chan...

Hot and Cool Spots of Primary Production, Respiration and 15N Nitrate and Ammonium Uptake: Spatial Heterogeneity in Tropical Streams and Rivers

NASA Astrophysics Data System (ADS)

Dodds, W. K.; Tromboni, F.; Neres-Lima, V.; Zandoná, E.; Moulton, T. P.

2016-12-01

While whole-stream measures of metabolism and uptake have become common methods to characterize biogeochemical transport and processing, less is known about how nitrogen (N) uptake, gross primary production (GPP) and ecosystem respiration (ER) covary among different stream substrata as smaller scales. We measured 15N ammonium and nitrate uptake seperately, and GPP and ER of ecosystem compartments (leaves, epilithon, sand-associated biota and macrophytes) in closed circulating chambers in three streams/ rivers of varied size. The streams drain pristine Brazilian Atlantic Rainforest watersheds and are all within a few km of eachother. The smallest stream had dense forest canopy cover; the largest river was almost completely open. GPP could not be detected in the closed canopy stream. Epilithon (biofilms on rocks) was a dominant compartment for GPP and N uptake in the two open streams, and macrophytes rivaled epilithon GPP and N uptake rates in the most open stream. Even though leaves covered only 1-3% of the stream bottom, they could account for around half of all the ER in the streams but almost no N uptake. Sand had minimal rates of N uptake, GPP and R associated with it in all streams due to relatively low organic material content. The data suggest that N uptake, GPP and ER of different substrata are not closely linked over relatively small spatial (dm) scales, and that different biogeochemical processes may map to different hot and cool spots for ecosystem rates.

Geochemical results from stream-water and stream-sediment samples collected in Colorado and New Mexico

USGS Publications Warehouse

Hageman, Philip L.; Todd, Andrew S.; Smith, Kathleen S.; DeWitt, Ed; Zeigler, Mathew P.

2013-01-01

Scientists from the U.S. Geological Survey are studying the relationship between watershed lithology and stream-water chemistry. As part of this effort, 60 stream-water samples and 43 corresponding stream-sediment samples were collected in 2010 and 2011 from locations in Colorado and New Mexico. Sample sites were selected from small to midsize watersheds composed of a high percentage of one rock type or geologic unit. Stream-water and stream-sediment samples were collected, processed, preserved, and analyzed in a consistent manner. This report releases geochemical data for this phase of the study.

Method for sequestering CO.sub.2 and SO.sub.2 utilizing a plurality of waste streams

DOEpatents

Soong, Yee [Monroeville, PA; Allen, Douglas E [Salem, MA; Zhu, Chen [Monroe County, IN

2011-04-12

A neutralization/sequestration process is provided for concomitantly addressing capture and sequestration of both CO.sub.2 and SO.sub.2 from industrial gas byproduct streams. The invented process concomitantly treats and minimizes bauxite residues from aluminum production processes and brine wastewater from oil/gas production processes. The benefits of this integrated approach to coincidental treatment of multiple industrial waste byproduct streams include neutralization of caustic byproduct such as bauxite residue, thereby decreasing the risk associated with the long-term storage and potential environmental of storing caustic materials, decreasing or obviating the need for costly treatment of byproduct brines, thereby eliminating the need to purchase CaO or similar scrubber reagents typically required for SO.sub.2 treatment of such gasses, and directly using CO.sub.2 from flue gas to neutralize bauxite residue/brine mixtures, without the need for costly separation of CO.sub.2 from the industrial byproduct gas stream by processes such as liquid amine-based scrubbers.

Fish relationships with large wood in small streams

Treesearch

C. Andrew Dolloff; Melvin L. Warren

2003-01-01

Many ecological processes are associated with large wood in streams, such as forming habitat critical for fish and a host of other organisms. Wood loading in streams varies with age and species of riparian vegetation, stream size, time since last disturbance, and history of land use. Changes in the landscape resulting from homesteading, agriculture, and logging have...

Particulate organic contributions from forests and streams: debris isn't so bad

Treesearch

C. Andrew Dolloff; Jackson R. Webster

2000-01-01

It is clear that the input of "debris" from terrestrial plants falling into streams is one of the most significant processes occurring at the interface of terrestrial and stream ecosystems. Organic matter?leaves, twigs, branches, and whole trees?provides energy, nutrients, and structure to streams flowing through forests. A host of vertebrate and invertebrate...

Riparian management in forests of the continental eastern United States

Treesearch

Elon S. Verry; James W. Hornbeck; C. Andrew Dolloff

2000-01-01

As we meditate on the management of stream riparian areas, it is clear that the input of "debris" from terrestrial plants falling into streams is one of the most significant processes occurring at the interface of terrestrial and stream ecosystems. Organic matter - leaves. twigs, branches, and whole trees - provides energy, nutrients, and structure to streams...

Increasing synchrony of high temperature and low flow in western North American streams: Double trouble for coldwater biota?

Treesearch

Ivan Arismendi; Mohammad Safeeq; Sherri L. Johnson; Jason B Dunham; Roy Haggerty

2013-01-01

Flow and temperature are strongly linked environmental factors driving ecosystem processes in streams. Stream temperature maxima (Tmax_w) and stream flow minima (Qmin) can create periods of stress for aquatic organisms. In mountainous areas, such as western North America, recent shifts toward an earlier spring peak flow and...

Groundwater exchanges near a channelized versus unmodified stream mouth discharging to a subalpine lake

USGS Publications Warehouse

Constantz, James; Naranjo, Ramon C.; Niswonger, Richard G.; Allander, Kip K.; Neilson, B.; Rosenberry, Donald O.; Smith, David W.; Rosecrans, C.; Stonestrom, David A.

2016-01-01

The terminus of a stream flowing into a larger river, pond, lake, or reservoir is referred to as the stream-mouth reach or simply the stream mouth. The terminus is often characterized by rapidly changing thermal and hydraulic conditions that result in abrupt shifts in surface water/groundwater (sw/gw) exchange patterns, creating the potential for unique biogeochemical processes and ecosystems. Worldwide shoreline development is changing stream-lake interfaces through channelization of stream mouths, i.e., channel straightening and bank stabilization to prevent natural meandering at the shoreline. In the central Sierra Nevada (USA), Lake Tahoe's shoreline has an abundance of both “unmodified” (i.e., not engineered though potentially impacted by broader watershed engineering) and channelized stream mouths. Two representative stream mouths along the lake's north shore, one channelized and one unmodified, were selected to compare and contrast water and heat exchanges. Hydraulic and thermal properties were monitored during separate campaigns in September 2012 and 2013 and sw/gw exchanges were estimated within the stream mouth-shoreline continuum. Heat-flow and water-flow patterns indicated clear differences in the channelized versus the unmodified stream mouth. For the channelized stream mouth, relatively modulated, cool-temperature, low-velocity longitudinal streambed flows discharged offshore beneath warmer buoyant lakeshore water. In contrast, a seasonal barrier bar formed across the unmodified stream mouth, creating higher-velocity subsurface flow paths and higher diurnal temperature variations relative to shoreline water. As a consequence, channelization altered sw/gw exchanges potentially altering biogeochemical processing and ecological systems in and near the stream mouth.

SOMKE: kernel density estimation over data streams by sequences of self-organizing maps.

PubMed

Cao, Yuan; He, Haibo; Man, Hong

2012-08-01

In this paper, we propose a novel method SOMKE, for kernel density estimation (KDE) over data streams based on sequences of self-organizing map (SOM). In many stream data mining applications, the traditional KDE methods are infeasible because of the high computational cost, processing time, and memory requirement. To reduce the time and space complexity, we propose a SOM structure in this paper to obtain well-defined data clusters to estimate the underlying probability distributions of incoming data streams. The main idea of this paper is to build a series of SOMs over the data streams via two operations, that is, creating and merging the SOM sequences. The creation phase produces the SOM sequence entries for windows of the data, which obtains clustering information of the incoming data streams. The size of the SOM sequences can be further reduced by combining the consecutive entries in the sequence based on the measure of Kullback-Leibler divergence. Finally, the probability density functions over arbitrary time periods along the data streams can be estimated using such SOM sequences. We compare SOMKE with two other KDE methods for data streams, the M-kernel approach and the cluster kernel approach, in terms of accuracy and processing time for various stationary data streams. Furthermore, we also investigate the use of SOMKE over nonstationary (evolving) data streams, including a synthetic nonstationary data stream, a real-world financial data stream and a group of network traffic data streams. The simulation results illustrate the effectiveness and efficiency of the proposed approach.

Ecosystem Services Provided by Stream Fishes

EPA Science Inventory

Stream fish provide important services to people, including recreation and food, regulation of ecosystem processes, and aesthetic benefits. If the services provided by fish in different streams can be measured, then they can be valued and considered in restoration decisions. We...

Reformer assisted lean NO.sub.x catalyst aftertreatment system and method

DOEpatents

Kalyanaraman, Mohan [Media, PA; Park, Paul W [Peoria, IL; Ragle, Christie S [Havana, IL

2010-06-29

A method and apparatus for catalytically processing a gas stream passing therethrough to reduce the presence of NO.sub.x therein, wherein the apparatus includes a first catalyst composed of a silver-containing alumina that is adapted for catalytically processing the gas stream at a first temperature range, a second catalyst composed of a copper-containing zeolite located downstream from the first catalyst, wherein the second catalyst is adapted for catalytically processing the gas stream at a lower second temperature range relative to the first temperature range, a hydrocarbon compound for injection into the gas stream upstream of the first catalyst to provide a reductant, and a reformer for reforming a portion of the hydrocarbon compound into H.sub.2 and/or oxygenated hydrocarbon for injection into the gas stream upstream of the first catalyst. The second catalyst is adapted to facilitate the reaction of reducing NOx into N.sub.2, whereby the intermediates are produced via the first catalyst reacting with NOx and hydrocarbons.

Decoupling of dissolved organic matter patterns between stream and riparian groundwater in a headwater forested catchment

NASA Astrophysics Data System (ADS)

Bernal, Susana; Lupon, Anna; Catalán, Núria; Castelar, Sara; Martí, Eugènia

2018-03-01

Streams are important sources of carbon to the atmosphere, though knowing whether they merely outgas terrestrially derived carbon dioxide or mineralize terrestrial inputs of dissolved organic matter (DOM) is still a big challenge in ecology. The objective of this study was to investigate the influence of riparian groundwater (GW) and in-stream processes on the temporal pattern of stream DOM concentrations and quality in a forested headwater stream, and whether this influence differed between the leaf litter fall (LLF) period and the remaining part of the year (non-LLF). The spectroscopic indexes (fluorescence index, biological index, humification index, and parallel factor analysis components) indicated that DOM had an eminently protein-like character and was most likely originated from microbial sources and recent biological activity in both stream water and riparian GW. However, paired samples of stream water and riparian GW showed that dissolved organic carbon (DOC) and nitrogen (DON) concentrations as well as the spectroscopic character of DOM differed between the two compartments throughout the year. A simple mass balance approach indicated that in-stream processes along the reach contributed to reducing DOC and DON fluxes by 50 and 30 %, respectively. Further, in-stream DOC and DON uptakes were unrelated to each other, suggesting that these two compounds underwent different biogeochemical pathways. During the LLF period, stream DOC and DOC : DON ratios were higher than during the non-LLF period, and spectroscopic indexes suggested a major influence of terrestrial vegetation on stream DOM. Our study highlights that stream DOM is not merely a reflection of riparian GW entering the stream and that headwater streams have the capacity to internally produce, transform, and consume DOM.

Stochastic modeling of Cryptosporidium parvum to predict transport, retention, and downstream exposure

NASA Astrophysics Data System (ADS)

Drummond, J. D.; Boano, F.; Atwill, E. R.; Li, X.; Harter, T.; Packman, A. I.

2016-12-01

Rivers are a means of rapid and long-distance transmission of pathogenic microorganisms from upstream terrestrial sources. Thus, significant fluxes of pathogen loads from agricultural lands can occur due to transport in surface waters. Pathogens enter streams and rivers in a variety of processes, notably overland flow, shallow groundwater discharge, and direct inputs from host populations such as humans and other vertebrate species. Viruses, bacteria, and parasites can enter a stream and persist in the environment for varying amounts of time. Of particular concern is the protozoal parasite, Cryptosporidium parvum, which can remain infective for weeks to months under cool and moist conditions, with the infectious state (oocysts) largely resistant to chlorination. In order to manage water-borne diseases more effectively we need to better predict how microbes behave in freshwater systems, particularly how they are transported downstream in rivers and in the process interact with the streambed and other solid surfaces. Microbes continuously immobilize and resuspend during downstream transport due to a variety of processes, such as gravitational settling, attachment to in-stream structures such as submerged macrophytes, and hyporheic exchange and filtration within underlying sediments. These various interactions result in a wide range of microbial residence times in the streambed and therefore influence the persistence of pathogenic microbes in the stream environment. We developed a stochastic mobile-immobile model to describe these microbial transport and retention processes in streams and rivers that also accounts for microbial inactivation. We used the model to assess the transport, retention, and inactivation of C. parvum within stream environments, specifically under representative flow conditions of California streams where C. parvum exposure can be at higher risk due to agricultural nonpoint sources. The results demonstrate that the combination of stream reach-scale analysis and multi-scale stochastic modeling improves assessment of C. parvum transport and retention in streams in order to predict downstream exposure to human communities, wildlife, and livestock.

40 CFR 63.149 - Control requirements for certain liquid streams in open systems within a chemical manufacturing...

Code of Federal Regulations, 2010 CFR

2010-07-01

... streams in open systems within a chemical manufacturing process unit. 63.149 Section 63.149 Protection of... open systems within a chemical manufacturing process unit. (a) The owner or operator shall comply with... Air Pollutants From the Synthetic Organic Chemical Manufacturing Industry for Process Vents, Storage...

Perception of Shapes Targeting Local and Global Processes in Autism Spectrum Disorders

ERIC Educational Resources Information Center

Grinter, Emma J.; Maybery, Murray T.; Pellicano, Elizabeth; Badcock, Johanna C.; Badcock, David R.

2010-01-01

Background: Several researchers have found evidence for impaired global processing in the dorsal visual stream in individuals with autism spectrum disorders (ASDs). However, support for a similar pattern of visual processing in the ventral visual stream is less consistent. Critical to resolving the inconsistency is the assessment of local and…

Diel biogeochemical processes and their effect on the aqueous chemistry of streams: A review

USGS Publications Warehouse

Nimick, David A.; Gammons, Christopher H.; Parker, Stephen R.

2011-01-01

This review summarizes biogeochemical processes that operate on diel, or 24-h, time scales in streams and the changes in aqueous chemistry that are associated with these processes. Some biogeochemical processes, such as those producing diel cycles of dissolved O2 and pH, were the first to be studied, whereas processes producing diel concentration cycles of a broader spectrum of chemical species including dissolved gases, dissolved inorganic and organic carbon, trace elements, nutrients, stable isotopes, and suspended particles have received attention only more recently. Diel biogeochemical cycles are interrelated because the cyclical variations produced by one biogeochemical process commonly affect another. Thus, understanding biogeochemical cycling is essential not only for guiding collection and interpretation of water-quality data but also for geochemical and ecological studies of streams. Expanded knowledge of diel biogeochemical cycling will improve understanding of how natural aquatic environments function and thus lead to better predictions of how stream ecosystems might react to changing conditions of contaminant loading, eutrophication, climate change, drought, industrialization, development, and other factors.

Applying the Principles of Lean Production to Gastrointestinal Biopsy Handling: From the Factory Floor to the Anatomic Pathology Laboratory.

PubMed

Sugianto, Jessica Z; Stewart, Brian; Ambruzs, Josephine M; Arista, Amanda; Park, Jason Y; Cope-Yokoyama, Sandy; Luu, Hung S

2015-01-01

To implement Lean principles to accommodate expanding volumes of gastrointestinal biopsies and to improve laboratory processes overall. Our continuous improvement (kaizen) project analyzed the current state for gastrointestinal biopsy handling using value-stream mapping for specimens obtained at a 487-bed tertiary care pediatric hospital in Dallas, Texas. We identified non-value-added time within the workflow process, from receipt of the specimen in the histology laboratory to the delivery of slides and paperwork to the pathologist. To eliminate non-value-added steps, we implemented the changes depicted in a revised-state value-stream map. Current-state value-stream mapping identified a total specimen processing time of 507 minutes, of which 358 minutes were non-value-added. This translated to a process cycle efficiency of 29%. Implementation of a revised-state value stream resulted in a total process time reduction to 238 minutes, of which 89 minutes were non-value-added, and an improved process cycle efficiency of 63%. Lean production principles of continuous improvement and waste elimination can be successfully implemented within the clinical laboratory.

Dynamic visualization of data streams

DOEpatents

Wong, Pak Chung [Richalnd, WA; Foote, Harlan P [Richland, WA; Adams, Daniel R [Kennewick, WA; Cowley, Wendy E [Richland, WA; Thomas, James J [Richland, WA

2009-07-07

One embodiment of the present invention includes a data communication subsystem to receive a data stream, and a data processing subsystem responsive to the data communication subsystem to generate a visualization output based on a group of data vectors corresponding to a first portion of the data stream. The processing subsystem is further responsive to a change in rate of receipt of the data to modify the visualization output with one or more other data vectors corresponding to a second portion of the data stream as a function of eigenspace defined with the group of data vectors. The system further includes a display device responsive to the visualization output to provide a corresponding visualization.

Stream Restoration to Manage Nutrients in Degraded Watersheds

EPA Science Inventory

Historic land-use change can reduce water quality by impairing the ability of stream ecosystems to efficiently process nutrients such as nitrogen. Study results of two streams (Minebank Run and Big Spring Run) affected by urbanization, quarrying, agriculture, and impoundments in...

COMPARTMENTAL MODEL OF NITRATE RETENTION IN STREAMS

EPA Science Inventory

A compartmental modeling approach is presented to route nitrate retention along a cascade of stream reach sections. A process transfer function is used for transient storage equations with first order reaction terms to represent nitrate uptake in the free stream, and denitrifica...

Stream primary producers relate positively to watershed natural gas measures in north-central Arkansas streams.

PubMed

Austin, Bradley J; Hardgrave, Natalia; Inlander, Ethan; Gallipeau, Cory; Entrekin, Sally; Evans-White, Michelle A

2015-10-01

Construction of unconventional natural gas (UNG) infrastructure (e.g., well pads, pipelines) is an increasingly common anthropogenic stressor that increases potential sediment erosion. Increased sediment inputs into nearby streams may decrease autotrophic processes through burial and scour, or sediment bound nutrients could have a positive effect through alleviating potential nutrient limitations. Ten streams with varying catchment UNG well densities (0-3.6 wells/km(2)) were sampled during winter and spring of 2010 and 2011 to examine relationships between landscape scale disturbances associated with UNG activity and stream periphyton [chlorophyll a (Chl a)] and gross primary production (GPP). Local scale variables including light availability and water column physicochemical variables were measured for each study site. Correlation analyses examined the relationships of autotrophic processes and local scale variables with the landscape scale variables percent pasture land use and UNG metrics (well density and well pad inverse flow path length). Both GPP and Chl a were primarily positively associated with the UNG activity metrics during most sample periods; however, neither landscape variables nor response variables correlated well with local scale factors. These positive correlations do not confirm causation, but they do suggest that it is possible that UNG development can alleviate one or more limiting factors on autotrophic production within these streams. A secondary manipulative study was used to examine the link between nutrient limitation and algal growth across a gradient of streams impacted by natural gas activity. Nitrogen limitation was common among minimally impacted stream reaches and was alleviated in streams with high UNG activity. These data provide evidence that UNG may stimulate the primary production of Fayetteville shale streams via alleviation of N-limitation. Restricting UNG activities from the riparian zone along with better enforcement of best management practices should help reduce these possible impacts of UNG activities on stream autotrophic processes. Copyright © 2015 Elsevier B.V. All rights reserved.

Continuous Dissolved Oxygen Measurements and Modelling Metabolism in Peatland Streams

PubMed Central

Dick, Jonathan J.; Soulsby, Chris; Birkel, Christian; Malcolm, Iain; Tetzlaff, Doerthe

2016-01-01

Stream water dissolved oxygen was monitored in a 3.2km2 moorland headwater catchment in the Scottish Highlands. The stream consists of three 1st order headwaters and a 2nd order main stem. The stream network is fringed by peat soils with no riparian trees, though dwarf shrubs provide shading in the lower catchment. Dissolved oxygen (DO) is regulated by the balance between atmospheric re-aeration and the metabolic processes of photosynthesis and respiration. DO was continuously measured for >1 year and the data used to calibrate a mass balance model, to estimate primary production, respiration and re-aeration for a 1st order site and in the 2nd order main stem. Results showed that the stream was always heterotrophic at both sites. Sites were most heterotrophic in the summer reflecting higher levels of stream metabolism. The 1st order stream appeared more heterotrophic which was consistent with the evident greater biomass of macrophytes in the 2nd order stream, with resulting higher primary productivity. Comparison between respiration, primary production, re-aeration and potential physical controls revealed only weak relationships. However, the most basic model parameters (e.g. the parameter linking light and photosynthesis) controlling ecosystem processes resulted in significant differences between the sites which seem related to the stream channel geometry. PMID:27556278

Perspectives on ecological research at the Outdoor StreamLab, a field-scale experimental stream

NASA Astrophysics Data System (ADS)

Merten, E. C.; Dieterman, D.; Kramarczuk, K.; Lightbody, A.; Orr, C. H.; Wellnitz, T.

2009-12-01

Artificial streams hold great promise for examining ecological processes. They lend themselves to manipulations of discharge, sediment load, water chemistry, and other parameters difficult or impossible to control in natural streams. However, artificial streams also have important limitations. In this presentation we describe insights gained from several ecological studies conducted at the St. Anthony Falls Laboratory’s Outdoor StreamLab, including, 1) short-term turbidity exposure effects on fish health, 2) macroinvertebrate grazing rates on periphyton as a function of velocity, 3) rates of macroinvertebrate colonization as related to velocity, and 4) fine-scale correlations of periphytic biomass with hydraulic conditions. Several lessons emerge from these initial attempts at ecological research in the Outdoor StreamLab. We have learned that the size, flow rate, substrate, water chemistry, and available colonization population of the artificial stream limit the kinds of organisms and types of ecological processes that can be examined and the types of experiments that can be run. We suggest that short-term biotic responses are best for study in a system of this type, and note that constant experiment maintenance is essential. Operating artificial streams to meet the needs of multiple researchers also presents challenges of scheduling, coordination, and conflict resolution. Although ecological research in artificial streams has considerable potential, the planning required is no less than that of traditional field studies.

Continuous countercurrent membrane column for the separation of solute/solvent and solvent/solvent systems

DOEpatents

Nerad, Bruce A.; Krantz, William B.

1988-01-01

A reverse osmosis membrane process or hybrid membrane - complementary separator process for producing enriched product or waste streams from concentrated and dilute feed streams for both solvent/solvent and solute/solvent systems is described.

Process for the production of ultrahigh purity silane with recycle from separation columns

NASA Technical Reports Server (NTRS)

Coleman, Larry M. (Inventor)

1982-01-01

Tri- and dichlorosilanes formed by hydrogenation in the course of the reaction of metallurgical silicon, hydrogen and recycle silicon tetrachloride are employed as feed into a separation column arrangement of sequential separation columns and redistribution reactors which processes the feed into ultrahigh purity silane and recycle silicon tetrachloride. A slip stream is removed from the bottom of two sequential columns and added to the recycle silicon tetrachloride process stream causing impurities in the slip streams to be subjected to reactions in the hydrogenation step whereby waste materials can be formed and readily separated.

Process for the production of ultrahigh purity silane with recycle from separation columns

DOEpatents

Coleman, Larry M.

1982-07-20

Tri- and dichlorosilanes formed by hydrogenation in the course of the reaction of metallurgical silicon, hydrogen and recycle silicon tetrachloride are employed as feed into a separation column arrangement of sequential separation columns and redistribution reactors which processes the feed into ultrahigh purity silane and recycle silicon tetrachloride. A slip stream is removed from the bottom of two sequential columns and added to the recycle silicon tetrachloride process stream causing impurities in the slip streams to be subjected to reactions in the hydrogenation step whereby waste materials can be formed and readily separated.

Falling microbead counter-flow process for separating gas mixtures

DOEpatents

Hornbostel, Marc D.; Krishnan, Gopala N.; Sanjurjo, Angel

2015-07-07

A method and reactor for removing a component from a gas stream is provided. In one embodiment, the method includes providing the gas stream containing the component that is to be removed and adsorbing the component out of the gas stream as the gas stream rises via microbeads of a sorbent falling down an adsorber section of a reactor.

Ash Tree Leaf Litter (Fraxinus excelsior L.) Breakdown in Two Different Biotopes and Streams

NASA Astrophysics Data System (ADS)

Fleituch, Tadeusz; Leichtfried, Maria

2004-11-01

Coarse (0.5 mm) and fine (0.1 mm) mesh size bag methodology was used for comparing the breakdown of ash tree leaves (Fraxinus excelsior L.) in two biotopes (dry - terrestrial and wet - overflown stream zones) in two low order streams (the Oberer Seebach (OSB), Lower Austria and the Brzezowka stream (BRZ), Beskidy Mountains, southern Poland). In total, 96 bags were exposed in autumn 2000. Ash-free dry mass (AFDM) ranged in dry zones of both streams from 94-62% (OSB) and 85-53% (BRZ) respectively. The decomposition process was faster in wet zones: 96-33% (OSB) and 56-11% (B) during the study period. Significant differences in ash breakdown and its chemical content between studied streams were found. Total organic carbon (TOC) and total nitrogen content (TN) of AFDM of litter showed increased differences with experiment duration between zones and between two bag types for both streams. The strongest increase of TOC and TN content (100% on average initial content) for bag types, zones, and streams was observed in the first two weeks of the experiment. These results confirm the importance of chemical compounds for microbiological processes (biofilms) in different ecosystem biotopes. (

A Control Chart Approach for Representing and Mining Data Streams with Shape Based Similarity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Omitaomu, Olufemi A

The mining of data streams for online condition monitoring is a challenging task in several domains including (electric) power grid system, intelligent manufacturing, and consumer science. Considering a power grid application in which thousands of sensors, called the phasor measurement units, are deployed on the power grid network to continuously collect streams of digital data for real-time situational awareness and system management. Depending on design, each sensor could stream between ten and sixty data samples per second. The myriad of sensory data captured could convey deeper insights about sequence of events in real-time and before major damages are done. However,more » the timely processing and analysis of these high-velocity and high-volume data streams is a challenge. Hence, a new data processing and transformation approach, based on the concept of control charts, for representing sequence of data streams from sensors is proposed. In addition, an application of the proposed approach for enhancing data mining tasks such as clustering using real-world power grid data streams is presented. The results indicate that the proposed approach is very efficient for data streams storage and manipulation.« less

An unexpected truth: increasing nitrate loading can decrease nitrate export from watersheds

NASA Astrophysics Data System (ADS)

Askarizadeh Bardsiri, A.; Grant, S. B.; Rippy, M.

2015-12-01

The discharge of anthropogenic nitrate (e.g., from partially treated sewage, return flows from agricultural irrigation, and runoff from animal feeding operations) to streams can negatively impact both human and ecosystem health. Managing these many point and non-point sources to achieve some specific end-point—for example, reducing the annual mass of nitrate exported from a watershed—can be a challenge, particularly in rapidly growing urban areas. Adding to this complexity is the fact that streams are not inert: they too can add or remove nitrate through assimilation (e.g., by stream-associated plants and animals) and microbially-mediated biogeochemical reactions that occur in streambed sediments (e.g., respiration, ammonification, nitrification, denitrification). By coupling a previously published correlation for in-stream processing of nitrate [Mulholland et al., Nature, 2008, 452, 202-205] with a stream network model of the Jacksons Creek watershed (Victoria, Australia) I demonstrate that managing anthropogenic sources of stream nitrate without consideration of in-stream processing can result in a number of non-intuitive "surprises"; for example, wastewater effluent discharges that increase nitrate loading but decrease in-stream nitrate concentrations can reduce the mass of nitrate exported from a watershed.

A quantitative analysis of hydraulic interaction processes in stream-aquifer systems

PubMed Central

Wang, Wenke; Dai, Zhenxue; Zhao, Yaqian; Li, Junting; Duan, Lei; Wang, Zhoufeng; Zhu, Lin

2016-01-01

The hydraulic relationship between the stream and aquifer can be altered from hydraulic connection to disconnection when the pumping rate exceeds the maximum seepage flux of the streambed. This study proposes to quantitatively analyze the physical processes of stream-aquifer systems from connection to disconnection. A free water table equation is adopted to clarify under what conditions a stream starts to separate hydraulically from an aquifer. Both the theoretical analysis and laboratory tests have demonstrated that the hydraulic connectedness of the stream-aquifer system can reach a critical disconnection state when the horizontal hydraulic gradient at the free water surface is equal to zero and the vertical is equal to 1. A boundary-value problem for movement of the critical point of disconnection is established for an analytical solution of the inverted water table movement beneath the stream. The result indicates that the maximum distance or thickness of the inverted water table is equal to the water depth in the stream, and at a steady state of disconnection, the maximum hydraulic gradient at the streambed center is 2. This study helps us to understand the hydraulic phenomena of water flow near streams and accurately assess surface water and groundwater resources. PMID:26818442

Process for Nitrogen Oxide Waste Conversion to Fertilizer

NASA Technical Reports Server (NTRS)

Lueck, Dale E. (Inventor); Parrish, Clyde F. (Inventor)

2003-01-01

The present invention describes a process for converting vapor streams from sources containing at least one nitrogen-containing oxidizing agent therein to a liquid fertilizer composition comprising the steps of: a) directing a vapor stream containing at least one nitrogen-containing oxidizing agent to a first contact zone; b) contacting said vapor stream with water to form nitrogen oxide(s) from said at least one nitrogen-containing oxidizing agent; c) directing said acid(s) as a second stream to a second contact zone; d) exposing said second stream to hydrogen peroxide which is present within said second contact zone in a relative amount of at least 0.1% by weight of said second stream within said second contact zone to convert at least some of any nitrogen oxide species or ions other than in the nitrate form present within said second stream to nitrate ion; e) sampling said stream within said second contact zone to determine the relative amount of hydrogen peroxide within said second contact zone; f) adding hydrogen peroxide to said second contact zone when a level of hydrogen peroxide less than 0.1 % by weight in said second stream is determined by said sampling; g) adding a solution comprising potassium hydroxide to said second stream to maintain a pH between 6.0 and 11.0 within said second stream within said second contact zone to form a solution of potassium nitrate; and h) removing said solution of potassium nitrate from said second contact zone.

Process and Equipment for Nitrogen Oxide Waste Conversion to Fertilizer

NASA Technical Reports Server (NTRS)

Lueck, Dale E. (Inventor); Parrish, Clyde F. (Inventor)

2000-01-01

The present invention describes a process for converting vapor streams from sources containing at least one nitrogen-containing oxidizing agent therein to a liquid fertilizer composition comprising the steps of: (1) directing a vapor stream containing at least nitrogen-containing oxidizing agent to a first contact zone; (2) contacting said vapor stream with water to form nitrogen oxide(s) from said at least one nitrogen- containing oxidizing agent; (3) directing said acid(s) as a second stream to a second contact zone; (4) exposing said second stream to hydrogen peroxide which is present within said second contact zone in a relative amount of at least 0.1% by weight of said second stream within said second contact zone to convert at least some of any nitrogen oxide species or ions other than in the nitrite form present within said second stream to nitrate ion; (5) sampling said stream within said second contact zone to determine the relative amount of hydrogen peroxide within said second contact zone; (6) adding hydrogen peroxide to said second contact zone when a level on hydrogen peroxide less than 0.1% by weight in said second stream is determined by said sampling; (7) adding a solution comprising potassium hydroxide to said second stream to maintain a pH between 6.0 and 11.0 within said second stream within said second contact zone to form a solution of potassium nitrate; and (8) removing sais solution of potassium nitrate from said second contact zone.

Environmental Characteristics and Geographic Information System Applications for the Development of Nutrient Thresholds in Oklahoma Streams

USGS Publications Warehouse

Masoner, Jason R.; Haggard, Brian E.; Rea, Alan

2002-01-01

The U.S.Environmental Protection Agency has developed nutrient criteria using ecoregions to manage and protect rivers and streams in the United States. Individual states and tribes are encouraged by the U.S. Environmental Protection Agency to modify or improve upon the ecoregion approach. The Oklahoma Water Resources Board uses a dichotomous process that stratifies streams using environmental characteristics such as stream order and stream slope. This process is called the Use Support Assessment Protocols, subchapter15. The Use Support Assessment Protocols can be used to identify streams threatened by excessive amounts of nutrients, dependant upon a beneficial use designation for each stream. The Use Support Assessment Protocols, subchapter 15 uses nutrient and environmental characteristic thresholds developed from a study conducted in the Netherlands, but the Oklahoma Water Resources Board wants to modify the thresholds to reflect hydrologic and ecological conditions relevant to Oklahoma streams and rivers. Environmental characteristics thought to affect impairment from nutrient concentrations in Oklahoma streams and rivers were determined for 798 water-quality sites in Oklahoma. Nutrient, chlorophyll, water-properties, and location data were retrieved from the U.S. Environmental Protection Agency STORET database including data from the U.S. Geological Survey, Oklahoma Conservation Commission, and Oklahoma Water Resources Board. Drainage-basin area, stream order, stream slope, and land-use proportions were determined for each site using a Geographic Information System. The methods, procedures, and data sets used to determine the environmental characteristics are described.

Syntactic processing in music and language: Effects of interrupting auditory streams with alternating timbres.

PubMed

Fiveash, Anna; Thompson, William Forde; Badcock, Nicholas A; McArthur, Genevieve

2018-07-01

Music and language both rely on the processing of spectral (pitch, timbre) and temporal (rhythm) information to create structure and meaning from incoming auditory streams. Behavioral results have shown that interrupting a melodic stream with unexpected changes in timbre leads to reduced syntactic processing. Such findings suggest that syntactic processing is conditional on successful streaming of incoming sequential information. The current study used event-related potentials (ERPs) to investigate whether (1) the effect of alternating timbres on syntactic processing is reflected in a reduced brain response to syntactic violations, and (2) the phenomenon is similar for music and language. Participants listened to melodies and sentences with either one timbre (piano or one voice) or three timbres (piano, guitar, and vibraphone, or three different voices). Half the stimuli contained syntactic violations: an out-of-key note in the melodies, and a phrase-structure violation in the sentences. We found smaller ERPs to syntactic violations in music in the three-timbre compared to the one-timbre condition, reflected in a reduced early right anterior negativity (ERAN). A similar but non-significant pattern was observed for language stimuli in both the early left anterior negativity (ELAN) and the left anterior negativity (LAN) ERPs. The results suggest that disruptions to auditory streaming may interfere with syntactic processing, especially for melodic sequences. Copyright © 2018 Elsevier B.V. All rights reserved.

Ion processing element with composite media

DOEpatents

Mann, Nick R.; Tranter, Troy J.; Todd, Terry A.; Sebesta, Ferdinand

2003-02-04

An ion processing element employing composite media disposed in a porous substrate, for facilitating removal of selected chemical species from a fluid stream. The ion processing element includes a porous fibrous glass substrate impregnated by composite media having one or more active components supported by a matrix material of polyacrylonitrile. The active components are effective in removing, by various mechanisms, one or more constituents from a fluid stream passing through the ion processing element. Due to the porosity and large surface area of both the composite medium and the substrate in which it is disposed, a high degree of contact is achieved between the active component and the fluid stream being processed. Further, the porosity of the matrix material and the substrate facilitates use of the ion processing element in high volume applications where it is desired to effectively process a high volume flows.

Ion processing element with composite media

DOEpatents

Mann, Nick R [Blackfoot, ID; Tranter, Troy J [Idaho Falls, ID; Todd, Terry A [Aberdeen, ID; Sebesta, Ferdinand [Prague, CZ

2009-03-24

An ion processing element employing composite media disposed in a porous substrate, for facilitating removal of selected chemical species from a fluid stream. The ion processing element includes a porous fibrous glass substrate impregnated by composite media having one or more active components supported by a matrix material of polyacrylonitrile. The active components are effective in removing, by various mechanisms, one or more constituents from a fluid stream passing through the ion processing element. Due to the porosity and large surface area of both the composite medium and the substrate in which it is disposed, a high degree of contact is achieved between the active component and the fluid stream being processed. Further, the porosity of the matrix material and the substrate facilitates use of the ion processing element in high volume applications where it is desired to effectively process a high volume flows.

Specificities of Acoustic Streaming in Cylindrical Cavity with Increasing Nonlinearity of the Process

NASA Astrophysics Data System (ADS)

Gubaidullin, A. A.; Pyatkova, A. V.

2018-01-01

This paper presents a numerical study of a gas acoustic streaming in a cylindrical cavity under a vibratory action. The walls of the cavity are considered impermeable and maintained at a constant temperature. The test gas is air. Variations in acoustic streaming and period-average temperature of the gas in the cavity with increasing nonlinearity of the process are shown. The increase in the nonlinearity is caused by an increase in the vibration amplitude.

Instream wood recruitment, channel complexity, and their relationship to stream ecology in forested headwater streams under alternative stable states

NASA Astrophysics Data System (ADS)

Livers, B.; Wohl, E.

2015-12-01

Human alteration to forests has had lasting effects on stream channels worldwide. Such land use changes affect how wood enters and is stored in streams as individual pieces and as logjams. Changes in wood recruitment affect the complexity and benefits wood can provide to the stream environment, such as zones of flow separation that store fine sediment and organic matter, increased nutrient processing, and greater habitat potential, which can enhance biota and cascade through stream-riparian ecosystems. Previous research in our study area shows that modern headwater streams flowing through old-growth, unmanaged forests have more wood than streams in young, managed forests, but does not explicitly evaluate how wood affects channel complexity or local ecology. 'Managed' refers to forests previously or currently exposed to human alteration. Alteration has long since ceased in some areas, but reduced wood loads in managed streams persist. Our primary objective was to quantify stream complexity metrics, with instream wood as a mediator, on streams across a gradient of management and disturbance histories in order to examine legacy effects of human alteration to forests. Data collected in the Southern Rocky Mountains include 24 2nd to 3rd order subalpine streams categorized into: old-growth unmanaged; younger, naturally disturbed unmanaged; and younger managed. We assessed instream wood loads and logjams and evaluated how they relate to channel complexity using a number of metrics, such as standard deviation of bed and banks, volume of pools, ratios of stream to valley lengths and stream to valley area, and diversity of substrate, gradient, and morphology. Preliminary results show that channel complexity is directly related to instream wood loads and is greatest in streams in old-growth. Related research in the field area indicates that streams with greater wood loads also have increased nutrient processing and greater abundance and diversity of aquatic insect predators.

Composite media for ion processing

DOEpatents

Mann, Nick R [Blackfoot, ID; Wood, Donald J [Peshastin, WA; Todd, Terry A [Aberdeen, ID; Sebesta, Ferdinand [Prague, CZ

2009-12-08

Composite media, systems, and devices for substantially removing, or otherwise processing, one or more constituents of a fluid stream. The composite media comprise a plurality of beads, each having a matrix substantially comprising polyacrylonitrile (PAN) and supporting one or more active components which are effective in removing, by various mechanisms, one or more constituents from a fluid stream. Due to the porosity and large surface area of the beads, a high level of contact is achieved between composite media of the present invention and the fluid stream being processed. Further, the homogeneity of the beads facilitates use of the beads in high volume applications where it is desired to effectively process a large volume of flow per unit of time.

Absorption process for producing oxygen and nitrogen and solution therefor

DOEpatents

Roman, Ian C.

1984-01-01

Process for the separation and purification of oxygen and nitrogen is disclosed which utilizes solutions of oxygen carriers to selectively absorb oxygen from a gaseous stream, leaving nitrogen as a byproduct. In the process, an oxygen carrier capable of reversibly binding molecular oxygen is dissolved in a solvent solution, which absorbs oxygen from an oxygen-containing gaseous feed stream such as atmospheric air and desorbs oxygen to a gaseous product stream. The feed stream is maintained at a sufficiently high oxygen pressure to keep the oxygen carrier in its oxygenated form during absorption, while the product stream is maintained at a sufficiently low oxygen pressure to keep the carrier in its deoxygenated form during desorption. In an alternate mode of operation, the carrier solution is maintained at a sufficiently low temperature and high oxygen pressure to keep the oxygen carrier in its oxygenated form during absorption, and at a sufficiently high temperature to keep the carrier in its deoxygenated form during desorption. Under such conditions, exceptionally high oxygen concentrations on the order of 95% to 99% are obtained, as well as a long carrier lifetime in excess of 3 months, making the process commercially feasible.

Mapping a lateralization gradient within the ventral stream for auditory speech perception.

PubMed

Specht, Karsten

2013-01-01

Recent models on speech perception propose a dual-stream processing network, with a dorsal stream, extending from the posterior temporal lobe of the left hemisphere through inferior parietal areas into the left inferior frontal gyrus, and a ventral stream that is assumed to originate in the primary auditory cortex in the upper posterior part of the temporal lobe and to extend toward the anterior part of the temporal lobe, where it may connect to the ventral part of the inferior frontal gyrus. This article describes and reviews the results from a series of complementary functional magnetic resonance imaging studies that aimed to trace the hierarchical processing network for speech comprehension within the left and right hemisphere with a particular focus on the temporal lobe and the ventral stream. As hypothesized, the results demonstrate a bilateral involvement of the temporal lobes in the processing of speech signals. However, an increasing leftward asymmetry was detected from auditory-phonetic to lexico-semantic processing and along the posterior-anterior axis, thus forming a "lateralization" gradient. This increasing leftward lateralization was particularly evident for the left superior temporal sulcus and more anterior parts of the temporal lobe.

Mapping a lateralization gradient within the ventral stream for auditory speech perception

PubMed Central

Specht, Karsten

2013-01-01

Recent models on speech perception propose a dual-stream processing network, with a dorsal stream, extending from the posterior temporal lobe of the left hemisphere through inferior parietal areas into the left inferior frontal gyrus, and a ventral stream that is assumed to originate in the primary auditory cortex in the upper posterior part of the temporal lobe and to extend toward the anterior part of the temporal lobe, where it may connect to the ventral part of the inferior frontal gyrus. This article describes and reviews the results from a series of complementary functional magnetic resonance imaging studies that aimed to trace the hierarchical processing network for speech comprehension within the left and right hemisphere with a particular focus on the temporal lobe and the ventral stream. As hypothesized, the results demonstrate a bilateral involvement of the temporal lobes in the processing of speech signals. However, an increasing leftward asymmetry was detected from auditory–phonetic to lexico-semantic processing and along the posterior–anterior axis, thus forming a “lateralization” gradient. This increasing leftward lateralization was particularly evident for the left superior temporal sulcus and more anterior parts of the temporal lobe. PMID:24106470

Multi-Scale Observation of Time-Variable Interactions of a Stream and its Valley Bottom During a Storm Event

NASA Astrophysics Data System (ADS)

Hixson, J.; Ward, A. S.; Schmadel, N.

2015-12-01

The exchange of water and solutes across the stream-hyporheic-riparian-hillslope continuum is controlled by the interaction of dynamic hydrological processes with the underlying geological setting. Our current understanding of exchange processes is primarily based on field observations collected during baseflow conditions, with few studies considering time-variable stream-aquifer interactions during storm events. We completed ten sets of four in-stream tracer slug injections during and after a large storm event in a headwater catchment at the H.J. Andrews Experimental Forest, Oregon. The injections were performed in three adjacent 50-meter study reaches, enabling comparison of spatial heterogeneity in transport processes. Reach-scale data demonstrate apparent trends with discharge in both transient storage and long-term storage (commonly "channel water balance"). Comparison of flowpath-scale observations from a network of monitoring wells to reach-scale observations showed that the advective timescale changed with discharge making it difficult to infer process from simple, reach-scale tracer studies. Overall, our results highlight the opportunities and challenges for interpretation of multi-scale solute tracer data along the stream-hyporheic-riparian-hillslope continuum.

Floodplain geomorphic processes and environmental impacts of human alteration along coastal plain rivers, USA

USGS Publications Warehouse

Hupp, C.R.; Pierce, Aaron R.; Noe, G.B.

2009-01-01

Human alterations along stream channels and within catchments have affected fluvial geomorphic processes worldwide. Typically these alterations reduce the ecosystem services that functioning floodplains provide; in this paper we are concerned with the sediment and associated material trapping service. Similarly, these alterations may negatively impact the natural ecology of floodplains through reductions in suitable habitats, biodiversity, and nutrient cycling. Dams, stream channelization, and levee/canal construction are common human alterations along Coastal Plain fluvial systems. We use three case studies to illustrate these alterations and their impacts on floodplain geomorphic and ecological processes. They include: 1) dams along the lower Roanoke River, North Carolina, 2) stream channelization in west Tennessee, and 3) multiple impacts including canal and artificial levee construction in the central Atchafalaya Basin, Louisiana. Human alterations typically shift affected streams away from natural dynamic equilibrium where net sediment deposition is, approximately, in balance with net erosion. Identification and understanding of critical fluvial parameters (e.g., stream gradient, grain-size, and hydrography) and spatial and temporal sediment deposition/erosion process trajectories should facilitate management efforts to retain and/or regain important ecosystem services. ?? 2009, The Society of Wetland Scientists.

Absorption process for producing oxygen and nitrogen and solution therefor

DOEpatents

Roman, Ian C. [Wilmington, DE; Baker, Richard W. [Palo Alto, CA

1990-09-25

Process for the separation and purification of oxygen and nitrogen is disclosed which utilizes solutions of oxygen carriers to selectively absorb oxygen from a gaseous stream, leaving nitrogen as a byproduct. In the process, an oxygen carrier capable of reversibly binding molecular oxygen is dissolved in a solvent solution, which absorbs oxygen from an oxygen-containing gaseous feed stream such as atmospheric air and desorbs oxygen to a gaseous product stream. The feed stream is maintained at a sufficiently high oxygen pressure to keep the oxygen carrier in its oxygenated form during absorption, while the product stream is maintained at a sufficiently low oxygen pressure to keep the carrier in its deoxygenated form during desorption. In an alternate mode of operation, the carrier solution is maintained at a sufficiently low temperature and high oxygen pressure to keep the oxygen carrier in its oxygenated form during absorption, and at a sufficiently high temperature to keep the carrier in its deoxygenated form during desorption. Under such conditions, exceptionally high oxygen concentrations on the order of 95% to 99% are obtained, as well as a long carrier lifetime in excess of 3 months, making the process commercially feasible.

Absorption process for producing oxygen and nitrogen and solution therefor

DOEpatents

Roman, I.C.; Baker, R.W.

1990-09-25

Process for the separation and purification of oxygen and nitrogen is disclosed which utilizes solutions of oxygen carriers to selectively absorb oxygen from a gaseous stream, leaving nitrogen as a byproduct. In the process, an oxygen carrier capable of reversibly binding molecular oxygen is dissolved in a solvent solution, which absorbs oxygen from an oxygen-containing gaseous feed stream such as atmospheric air and desorbs oxygen to a gaseous product stream. The feed stream is maintained at a sufficiently high oxygen pressure to keep the oxygen carrier in its oxygenated form during absorption, while the product stream is maintained at a sufficiently low oxygen pressure to keep the carrier in its deoxygenated form during desorption. In an alternate mode of operation, the carrier solution is maintained at a sufficiently low temperature and high oxygen pressure to keep the oxygen carrier in its oxygenated form during absorption, and at a sufficiently high temperature to keep the carrier in its deoxygenated form during desorption. Under such conditions, exceptionally high oxygen concentrations on the order of 95% to 99% are obtained, as well as a long carrier lifetime in excess of 3 months, making the process commercially feasible. 1 figure

USE OF HEMISPHERIC IMAGERY FOR ESTIMATING STREAM SOLAR EXPOSURE

EPA Science Inventory

Solar exposure profoundly affects stream processes and species composition. Despite this, prominent stream monitoring protocols focus on canopy closure (obstruction of the sky as a whole) rather than on measures of solar exposure or shading. We identify a candidate set of solar...

Effective discharge analysis of ecological processes in streams

USGS Publications Warehouse

Doyle, Martin W.; Stanley, Emily H.; Strayer, David L.; Jacobson, Robert B.; Schmidt, John C.

2005-01-01

Discharge is a master variable that controls many processes in stream ecosystems. However, there is uncertainty of which discharges are most important for driving particular ecological processes and thus how flow regime may influence entire stream ecosystems. Here the analytical method of effective discharge from fluvial geomorphology is used to analyze the interaction between frequency and magnitude of discharge events that drive organic matter transport, algal growth, nutrient retention, macroinvertebrate disturbance, and habitat availability. We quantify the ecological effective discharge using a synthesis of previously published studies and modeling from a range of study sites. An analytical expression is then developed for a particular case of ecological effective discharge and is used to explore how effective discharge varies within variable hydrologic regimes. Our results suggest that a range of discharges is important for different ecological processes in an individual stream. Discharges are not equally important; instead, effective discharge values exist that correspond to near modal flows and moderate floods for the variable sets examined. We suggest four types of ecological response to discharge variability: discharge as a transport mechanism, regulator of habitat, process modulator, and disturbance. Effective discharge analysis will perform well when there is a unique, essentially instantaneous relationship between discharge and an ecological process and poorly when effects of discharge are delayed or confounded by legacy effects. Despite some limitations the conceptual and analytical utility of the effective discharge analysis allows exploring general questions about how hydrologic variability influences various ecological processes in streams.

Advanced evaporator technology progress report FY 1992

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chamberlain, D.; Hutter, J.C.; Leonard, R.A.

1995-01-01

This report summarizes the work that was completed in FY 1992 on the program {open_quotes}Technology Development for Concentrating Process Streams.{close_quotes} The purpose of this program is to evaluate and develop evaporator technology for concentrating radioactive waste and product streams such as those generated by the TRUEX process. Concentrating these streams and minimizing the volume of waste generated can significantly reduce disposal costs; however, equipment to concentrate the streams and recycle the decontaminated condensates must be installed. LICON, Inc., is developing an evaporator that shows a great deal of potential for this application. In this report, concepts that need to bemore » incorporated into the design of an evaporator operated in a radioactive environment are discussed. These concepts include criticality safety, remote operation and maintenance, and materials of construction. Both solubility and vapor-liquid equilibrium data are needed to design an effective process for concentrating process streams. Therefore, literature surveys were completed and are summarized in this report. A model that is being developed to predict vapor phase compositions is described. A laboratory-scale evaporator was purchased and installed to study the evaporation process and to collect additional data. This unit is described in detail. Two new LICON evaporators are being designed for installation at Argonne-East in FY 1993 to process low-level radioactive waste generated throughout the laboratory. They will also provide operating data from a full-sized evaporator processing radioactive solutions. Details on these evaporators are included in this report.« less

Video streaming technologies using ActiveX and LabVIEW

NASA Astrophysics Data System (ADS)

Panoiu, M.; Rat, C. L.; Panoiu, C.

2015-06-01

The goal of this paper is to present the possibilities of remote image processing through data exchange between two programming technologies: LabVIEW and ActiveX. ActiveX refers to the process of controlling one program from another via ActiveX component; where one program acts as the client and the other as the server. LabVIEW can be either client or server. Both programs (client and server) exist independent of each other but are able to share information. The client communicates with the ActiveX objects that the server opens to allow the sharing of information [7]. In the case of video streaming [1] [2], most ActiveX controls can only display the data, being incapable of transforming it into a data type that LabVIEW can process. This becomes problematic when the system is used for remote image processing. The LabVIEW environment itself provides little if any possibilities for video streaming, and the methods it does offer are usually not high performance, but it possesses high performance toolkits and modules specialized in image processing, making it ideal for processing the captured data. Therefore, we chose to use existing software, specialized in video streaming along with LabVIEW and to capture the data provided by them, for further use, within LabVIEW. The software we studied (the ActiveX controls of a series of media players that utilize streaming technology) provide high quality data and a very small transmission delay, ensuring the reliability of the results of the image processing.

Impacts of Invasive Rusty Crayfish on Stream Ecosystems of the Upper Midwestern U.S.

NASA Astrophysics Data System (ADS)

Bobeldyk, A. M.; Lamberti, G. A.

2005-05-01

Invasive species can have detrimental effects on structural characteristics of freshwater ecosystems, but relatively few studies have assessed ecosystem-level impacts of invasive species in streams. We studied the effects of invasive rusty crayfish (Orconectes rusticus) on detritus processing and invertebrate and fish abundance in northern Wisconsin and Michigan, USA, streams. We hypothesized that rusty crayfish would increase the rate of detritus processing and reduce fish and invertebrate abundance due to their aggressiveness and competitive superiority for food and habitat. We measured sugar maple (Acer saccharum) decomposition rates in three reaches of a stream with differing densities of rusty crayfish, high (5.05/m2), intermediate (2.27/m2), and none (0/m2) using leaf bags excluding crayfish and open bags allowing crayfish access. We found that open bags decayed significantly faster (k=0.143) than crayfish excluded bags at all sites (k=0.079) (p=0.0005). The reach lacking crayfish had significantly higher densities of invertebrates (p=0.005). We also surveyed an additional 7 streams that contained or lacked rusty crayfish and found significantly higher fish abundance (p=0.019) and biomass (p=0.001) in streams lacking rusty crayfish. Rusty crayfish appear to indirectly affect detritus processing via negative effects on benthic invertebrates, and may have larger-scale impacts on fishes across streams.

Stream fish colonization but not persistence varies regionally across a large North American river basin

USGS Publications Warehouse

Wheeler, Kit; Wengerd, Seth J.; Walsh, Stephen J.; Martin, Zachary P.; Jelks, Howard L.; Freeman, Mary C.

2018-01-01

Many species have distributions that span distinctly different physiographic regions, and effective conservation of such taxa will require a full accounting of all factors that potentially influence populations. Ecologists recognize effects of physiographic differences in topography, geology and climate on local habitat configurations, and thus the relevance of landscape heterogeneity to species distributions and abundances. However, research is lacking that examines how physiography affects the processes underlying metapopulation dynamics. We used data describing occupancy dynamics of stream fishes to evaluate evidence that physiography influences rates at which individual taxa persist in or colonize stream reaches under different flow conditions. Using periodic survey data from a stream fish assemblage in a large river basin that encompasses multiple physiographic regions, we fit multi-species dynamic occupancy models. Our modeling results suggested that stream fish colonization but not persistence was strongly governed by physiography, with estimated colonization rates considerably higher in Coastal Plain streams than in Piedmont and Blue Ridge systems. Like colonization, persistence was positively related to an index of stream flow magnitude, but the relationship between flow and persistence did not depend on physiography. Understanding the relative importance of colonization and persistence, and how one or both processes may change across the landscape, is critical information for the conservation of broadly distributed taxa, and conservation strategies explicitly accounting for spatial variation in these processes are likely to be more successful for such taxa.

Emotion processing in the visual brain: a MEG analysis.

PubMed

Peyk, Peter; Schupp, Harald T; Elbert, Thomas; Junghöfer, Markus

2008-06-01

Recent functional magnetic resonance imaging (fMRI) and event-related brain potential (ERP) studies provide empirical support for the notion that emotional cues guide selective attention. Extending this line of research, whole head magneto-encephalogram (MEG) was measured while participants viewed in separate experimental blocks a continuous stream of either pleasant and neutral or unpleasant and neutral pictures, presented for 330 ms each. Event-related magnetic fields (ERF) were analyzed after intersubject sensor coregistration, complemented by minimum norm estimates (MNE) to explore neural generator sources. Both streams of analysis converge by demonstrating the selective emotion processing in an early (120-170 ms) and a late time interval (220-310 ms). ERF analysis revealed that the polarity of the emotion difference fields was reversed across early and late intervals suggesting distinct patterns of activation in the visual processing stream. Source analysis revealed the amplified processing of emotional pictures in visual processing areas with more pronounced occipito-parieto-temporal activation in the early time interval, and a stronger engagement of more anterior, temporal, regions in the later interval. Confirming previous ERP studies showing facilitated emotion processing, the present data suggest that MEG provides a complementary look at the spread of activation in the visual processing stream.

Performance of the air2stream model that relates air and stream water temperatures depends on the calibration method

NASA Astrophysics Data System (ADS)

Piotrowski, Adam P.; Napiorkowski, Jaroslaw J.

2018-06-01

A number of physical or data-driven models have been proposed to evaluate stream water temperatures based on hydrological and meteorological observations. However, physical models require a large amount of information that is frequently unavailable, while data-based models ignore the physical processes. Recently the air2stream model has been proposed as an intermediate alternative that is based on physical heat budget processes, but it is so simplified that the model may be applied like data-driven ones. However, the price for simplicity is the need to calibrate eight parameters that, although have some physical meaning, cannot be measured or evaluated a priori. As a result, applicability and performance of the air2stream model for a particular stream relies on the efficiency of the calibration method. The original air2stream model uses an inefficient 20-year old approach called Particle Swarm Optimization with inertia weight. This study aims at finding an effective and robust calibration method for the air2stream model. Twelve different optimization algorithms are examined on six different streams from northern USA (states of Washington, Oregon and New York), Poland and Switzerland, located in both high mountains, hilly and lowland areas. It is found that the performance of the air2stream model depends significantly on the calibration method. Two algorithms lead to the best results for each considered stream. The air2stream model, calibrated with the chosen optimization methods, performs favorably against classical streamwater temperature models. The MATLAB code of the air2stream model and the chosen calibration procedure (CoBiDE) are available as Supplementary Material on the Journal of Hydrology web page.

What controls channel form in steep mountain streams?

NASA Astrophysics Data System (ADS)

Palucis, M. C.; Lamb, M. P.

2017-07-01

Steep mountain streams have channel morphologies that transition from alternate bar to step-pool to cascade with increasing bed slope, which affect stream habitat, flow resistance, and sediment transport. Experimental and theoretical studies suggest that alternate bars form under large channel width-to-depth ratios, step-pools form in near supercritical flow or when channel width is narrow compared to bed grain size, and cascade morphology is related to debris flows. However, the connection between these process variables and bed slope—the apparent dominant variable for natural stream types—is unclear. Combining field data and theory, we find that certain bed slopes have unique channel morphologies because the process variables covary systematically with bed slope. Multiple stable states are predicted for other ranges in bed slope, suggesting that a competition of underlying processes leads to the emergence of the most stable channel form.

Microbial Biomass and Activity in Geomorphic Features in Forested and Urban Restored and Degraded Streams

EPA Science Inventory

Geomorphic spatial heterogeneity affects sediment denitrification, an anaerobic microbial process that results in the loss of nitrogen (N), and other anaerobic microbial processes such as methanogenesis in urban streams. We measured sediment denitrification potential (DEA), metha...

Restoring “hot spots” of denitrification along hydrologic flow-paths

EPA Science Inventory

Objectives: What are the relationships among N, C, and hydrology in degraded streams? What level of biogeochemical function remains with respect to N transformation processes (i.e. denitrification)? What could the results tell us about effectively restoring streams to process ...

ON THE HYDRAULICS OF STREAM FLOW ROUTING WITH BANK STORAGE

EPA Science Inventory

Bank storage is a process in which volumes of water are temporally retained by alluvial stream banks during flood events, and gradually released to partially sustain baseflow. This process has important hydrologic and ecological implications. In this paper, analytical solutions a...

Anatomy of aphasia revisited.

PubMed

Fridriksson, Julius; den Ouden, Dirk-Bart; Hillis, Argye E; Hickok, Gregory; Rorden, Chris; Basilakos, Alexandra; Yourganov, Grigori; Bonilha, Leonardo

2018-01-17

In most cases, aphasia is caused by strokes involving the left hemisphere, with more extensive damage typically being associated with more severe aphasia. The classical model of aphasia commonly adhered to in the Western world is the Wernicke-Lichtheim model. The model has been in existence for over a century, and classification of aphasic symptomatology continues to rely on it. However, far more detailed models of speech and language localization in the brain have been formulated. In this regard, the dual stream model of cortical brain organization proposed by Hickok and Poeppel is particularly influential. Their model describes two processing routes, a dorsal stream and a ventral stream, that roughly support speech production and speech comprehension, respectively, in normal subjects. Despite the strong influence of the dual stream model in current neuropsychological research, there has been relatively limited focus on explaining aphasic symptoms in the context of this model. Given that the dual stream model represents a more nuanced picture of cortical speech and language organization, cortical damage that causes aphasic impairment should map clearly onto the dual processing streams. Here, we present a follow-up study to our previous work that used lesion data to reveal the anatomical boundaries of the dorsal and ventral streams supporting speech and language processing. Specifically, by emphasizing clinical measures, we examine the effect of cortical damage and disconnection involving the dorsal and ventral streams on aphasic impairment. The results reveal that measures of motor speech impairment mostly involve damage to the dorsal stream, whereas measures of impaired speech comprehension are more strongly associated with ventral stream involvement. Equally important, many clinical tests that target behaviours such as naming, speech repetition, or grammatical processing rely on interactions between the two streams. This latter finding explains why patients with seemingly disparate lesion locations often experience similar impairments on given subtests. Namely, these individuals' cortical damage, although dissimilar, affects a broad cortical network that plays a role in carrying out a given speech or language task. The current data suggest this is a more accurate characterization than ascribing specific lesion locations as responsible for specific language deficits.awx363media15705668782001. © The Author(s) (2018). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Development And Initial Testing Of Off-Gas Recycle Liquid From The WTP Low Activity Waste Vitrification Process - 14333

DOE Office of Scientific and Technical Information (OSTI.GOV)

McCabe, Daniel J.; Wilmarth, William R.; Nash, Charles A.

2014-01-07

The Waste Treatment and Immobilization Plant (WTP) process flow was designed to pre-treat feed from the Hanford tank farms, separate it into a High Level Waste (HLW) and Low Activity Waste (LAW) fraction and vitrify each fraction in separate facilities. Vitrification of the waste generates an aqueous condensate stream from the off-gas processes. This stream originates from two off-gas treatment unit operations, the Submerged Bed Scrubber (SBS) and the Wet Electrospray Precipitator (WESP). Currently, the baseline plan for disposition of the stream from the LAW melter is to recycle it to the Pretreatment facility where it gets evaporated and processedmore » into the LAW melter again. If the Pretreatment facility is not available, the baseline disposition pathway is not viable. Additionally, some components in the stream are volatile at melter temperatures, thereby accumulating to high concentrations in the scrubbed stream. It would be highly beneficial to divert this stream to an alternate disposition path to alleviate the close-coupled operation of the LAW vitrification and Pretreatment facilities, and to improve long-term throughput and efficiency of the WTP system. In order to determine an alternate disposition path for the LAW SBS/WESP Recycle stream, a range of options are being studied. A simulant of the LAW Off-Gas Condensate was developed, based on the projected composition of this stream, and comparison with pilot-scale testing. The primary radionuclide that vaporizes and accumulates in the stream is Tc-99, but small amounts of several other radionuclides are also projected to be present in this stream. The processes being investigated for managing this stream includes evaporation and radionuclide removal via precipitation and adsorption. During evaporation, it is of interest to investigate the formation of insoluble solids to avoid scaling and plugging of equipment. Key parameters for radionuclide removal include identifying effective precipitation or ion adsorption chemicals, solid-liquid separation methods, and achievable decontamination factors. Results of the radionuclide removal testing indicate that the radionuclides, including Tc-99, can be removed with inorganic sorbents and precipitating agents. Evaporation test results indicate that the simulant can be evaporated to fairly high concentration prior to formation of appreciable solids, but corrosion has not yet been examined.« less

IN-STREAM AND WATERSHED PREDICTORS OF GENETIC DIVERSITY, EFFECTIVE POPULATION SIZE AND IMMIGRATION ACROSS RIVER-STREAM NETWORKS

EPA Science Inventory

The influence of spatial processes on population dynamics within river-stream networks is poorly understood. Utilizing spatially explicit analyses of temporal genetic variance, we examined whether persistence of Central Stonerollers (Campostoma anomalum) reflects differences in h...

Biogeochemistry and Hydrology in Streams Impacted by Legacy Sediments and Urbanization: Implications for Stream Restoration

EPA Science Inventory

The groundwater–surface water interface, consisting of shallow groundwater adjacent to stream channels, is a hot spot for nitrogen removal processes, a storage zone for other solutes, and a target for restoration activities. Characterizing groundwater-surface water interac...

GEOMORPHIC CONTROLS ON C AND N PROCESSING IN A RESTORED URBAN STREAM; POWER POINT PRESENTATION

EPA Science Inventory

Stream channel incision due to hydraulic alteration stemming from urbanization may cause a disconnection between the stream channel and the adjacent floodplain. This disconnection may inhibit removal of nitrate via denitrification and/or stimulate nitrate production through nitr...

Effect of initial conditions on constant pressure mixing between two turbulent streams

NASA Astrophysics Data System (ADS)

Kangovi, S.

1983-02-01

It is pointed out that a study of the process of mixing between two dissimilar streams has varied applications in different fields. The applications include the design of an after burner in a high by-pass ratio aircraft engine and the disposal of effluents in a stream. The mixing process determines important quantities related to the energy transfer from main stream to the secondary stream, the temperature and velocity profiles, and the local kinematic and dissipative structure within the mixing region, and the growth of the mixing layer. Hill and Page (1968) have proposed the employment of an 'assumed epsilon' method in which the eddy viscosity model of Goertler (1942) is modified to account for the initial boundary layer. The present investigation is concerned with the application of the assumed epsilon technique to the study of the effect of initial conditions on the development of the turbulent mixing layer between two compressible, nonisoenergetic streams at constant pressure.

Method for the removal of ultrafine particulates from an aqueous suspension

DOEpatents

Chaiko, David J.; Kopasz, John P.; Ellison, Adam J. G.

2000-01-01

A method of separating ultra-fine particulates from an aqueous suspension such as a process stream or a waste stream. The method involves the addition of alkali silicate and an organic gelling agent to a volume of liquid, from the respective process or waste stream, to form a gel. The gel then undergoes syneresis to remove water and soluble salts from the gel containing the particulates, thus, forming a silica monolith. The silica monolith is then sintered to form a hard, nonporous waste form.

Users' manual for the Hydroecological Integrity Assessment Process software (including the New Jersey Assessment Tools)

USGS Publications Warehouse

Henriksen, James A.; Heasley, John; Kennen, Jonathan G.; Nieswand, Steven

2006-01-01

Applying the Hydroecological Integrity Assessment Process involves four steps: (1) a hydrologic classification of relatively unmodified streams in a geographic area using long-term gage records and 171 ecologically relevant indices; (2) the identification of statistically significant, nonredundant, hydroecologically relevant indices associated with the five major flow components for each stream class; and (3) the development of a stream-classification tool and a hydrologic assessment tool. Four computer software tools have been developed.

Method for the Removal of Ultrafine Particulates from an Aqueous Suspension

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chaiko, David J.; Kopasz, John P.; Ellison, Adam J.G.

1999-03-05

A method of separating ultra-fine particulate from an aqueous suspension such as a process stream or a waste stream. The method involves the addition of alkali silicate and an organic gelling agent to a volume of liquid, from the respective process or waste stream, to form a gel. The gel then undergoes syneresis to remove water and soluble salts from the gel-containing the particulate, thus, forming a silica monolith. The silica monolith is then sintered to form a hard, nonporous waste form.

Process of forming catalytic surfaces for wet oxidation reactions

NASA Technical Reports Server (NTRS)

Jagow, R. B. (Inventor)

1977-01-01

A wet oxidation process was developed for oxidizing waste materials, comprising dissolved ruthenium salt in a reactant feed stream containing the waste materials. The feed stream is introduced into a reactor, and the reactor contents are then raised to an elevated temperature to effect deposition of a catalytic surface of ruthenium black on the interior walls of the reactor. The feed stream is then maintained in the reactor for a period of time sufficient to effect at least partial oxidation of the waste materials.

Understanding Groundwater and Surface Water Exchange Processes Along a Controlled Stream Using Thermal Remote Sensing and In-Situ Measurements

NASA Astrophysics Data System (ADS)

Varli, D.; Yilmaz, K. K.

2016-12-01

Effective management of water resources requires understanding and quantification of interaction between groundwater and surface water bodies. Moreover, the exchange processes have recently received increasing attention due to important influences on biogeochemical and ecological status of watersheds. In this study we investigated the exchange processes between surface water and groundwater along Kirmir stream - a controlled stream nearby Kizilcahamam, Ankara, Turkey. At the first stage, potential stream reaches where the exchange processes could occur were pinpointed using geological and geomorphological information. Then, thermal remote sensing was utilized to further narrow down the potential locations in which interaction could occur at a smaller scale. Nested piezometers were installed at identified locations to observe the variations in vertical hydraulic gradient over time. Differential discharge measurements were performed to understand the gains and losses along the stream reach. Streambed temperature measurements were taken at two different depths for a period of time using temperature loggers to calculate the vertical fluid fluxes through the streambed at various locations. Basic water quality field parameters (temperature, electrical conductivity, total dissolved solid amount, dissolved oxygen, pH and oxidation - reduction potential) were measured along the stream reach, from surface water and the piezometers as wells as from the nearby springs and wells. Chloride mass balance was performed to find the contribution of groundwater and chloride concentrations were associated with the geology of the area. This hierarchical, multi-scale methodology provided an efficient and effective way to determine the locations and the direction of groundwater and surface water exchange processes within the study area.

PROCESS TRANSFER FUNCTIONS TO RELATE STREAM ECOLOGICAL CONDITION METRICS TO NITRATE RETENTION

EPA Science Inventory

Ecologists have developed hydrological metrics to characterize the nutrient processing capability of streams. In most cases these are used qualitatively to draw inferences on ecological function. In this work, several of these metrics have been integrated in a nonsteady state adv...

INTELLIGENT DECISION SUPPORT FOR WASTE MINIMIZATION IN ELECTROPLATING PLANTS. (R824732)

EPA Science Inventory

Abstract

Wastewater, spent solvent, spent process solutions, and sludge are the major waste streams generated in large volumes daily in electroplating plants. These waste streams can be significantly minimized through process modification and operational improvement. I...

An industrial ecology approach to municipal solid waste ...

EPA Pesticide Factsheets

Municipal solid waste (MSW) can be viewed as a feedstock for industrial ecology inspired conversions of wastes to valuable products and energy. The industrial ecology principle of symbiotic processes using waste streams for creating value-added products is applied to MSW, with examples suggested for various residual streams. A methodology is presented to consider individual waste-to-energy or waste-to-product system synergies, evaluating the economic and environmental issues associated with each system. Steps included in the methodology include identifying waste streams, specific waste components of interest, and conversion technologies, plus steps for determining the economic and environmental effects of using wastes and changes due to transport, administrative handling, and processing. In addition to presenting the methodology, technologies for various MSW input streams are categorized as commercialized or demonstrated to provide organizations that are considering processes for MSW with summarized information. The organization can also follow the methodology to analyze interesting processes. Presents information useful for analyzing the sustainability of alternatives for the management of municipal solid waste.

The influence of attention on value integration.

PubMed

Kunar, Melina A; Watson, Derrick G; Tsetsos, Konstantinos; Chater, Nick

2017-08-01

People often have to make decisions based on many pieces of information. Previous work has found that people are able to integrate values presented in a rapid serial visual presentation (RSVP) stream to make informed judgements on the overall stream value (Tsetsos et al. Proceedings of the National Academy of Sciences of the United States of America, 109(24), 9659-9664, 2012). It is also well known that attentional mechanisms influence how people process information. However, it is unknown how attentional factors impact value judgements of integrated material. The current study is the first of its kind to investigate whether value judgements are influenced by attentional processes when assimilating information. Experiments 1-3 examined whether the attentional salience of an item within an RSVP stream affected judgements of overall stream value. The results showed that the presence of an irrelevant high or low value salient item biased people to judge the stream as having a higher or lower overall mean value, respectively. Experiments 4-7 directly tested Tsetsos et al.'s (Proceedings of the National Academy of Sciences of the United States of America, 109(24), 9659-9664, 2012) theory examining whether extreme values in an RSVP stream become over-weighted, thereby capturing attention more than other values in the stream. The results showed that the presence of both a high (Experiments 4, 6 and 7) and a low (Experiment 5) value outlier captures attention leading to less accurate report of subsequent items in the stream. Taken together, the results showed that valuations can be influenced by attentional processes, and can lead to less accurate subjective judgements.

Tracing Nitrate Contributions to Streams During Varying Flow Regimes at the Sleepers River Research Watershed, Vermont, USA

NASA Astrophysics Data System (ADS)

Sebestyen, S. D.; Shanley, J. B.; Boyer, E. W.; Ohte, N.; Doctor, D. H.; Kendall, C.

2003-12-01

Quantifying sources and transformations of nitrate in headwater catchments is fundamental to understanding the movement of nitrogen to streams. At the Sleepers River Research Watershed in northeastern Vermont (USA), we are using multiple chemical tracer and mixing model approaches to quantify sources and transport of nitrate to streams under varying flow regimes. We sampled streams, lysimeters, and wells at nested locations from the headwaters to the outlet of the 41 ha W-9 watershed under the entire range of flow regimes observed throughout 2002-2003, including baseflow and multiple events (stormflow and snowmelt). Our results suggest that nitrogen sources, and consequently stream nitrate concentrations, are rapidly regenerated during several weeks of baseflow and nitrogen is flushed from the watershed by stormflow events that follow baseflow periods. Both basic chemistry data (anions, cations, & dissolved organic carbon) and isotopic data (nitrate, dissolved organic carbon, and dissolved inorganic carbon) indicate that nitrogen source contributions vary depending upon the extent of saturation in the watershed, the initiation of shallow subsurface water inputs, and other hydrological processes. Stream nitrate concentrations typically peak with discharge and are higher on the falling than the rising limb of the hydrograph. Our data also indicate the importance of terrestrial and aquatic biogeochemical processes, in addition to hydrological connectivity in controlling how nitrate moves from the terrestrial landscape to streams. Our detailed sampling data from multiple flow regimes are helping to identify and quantify the "hot spots" and "hot moments" of biogeochemical and hydrological processes that control nitrogen fluxes in streams.

Sources, transformations, and hydrological processes that control stream nitrate and dissolved organic matter concentrations during snowmelt in an upland forest

USGS Publications Warehouse

Sebestyen, Stephen D.; Boyer, Elizabeth W.; Shanley, James B.; Kendall, Carol; Doctor, Daniel H.; Aiken, George R.; Ohte, Nobuhito

2008-01-01

We explored catchment processes that control stream nutrient concentrations at an upland forest in northeastern Vermont, USA, where inputs of nitrogen via atmospheric deposition are among the highest in the nation and affect ecosystem functioning. We traced sources of water, nitrate, and dissolved organic matter (DOM) using stream water samples collected at high frequency during spring snowmelt. Hydrochemistry, isotopic tracers, and end‐member mixing analyses suggested the timing, sources, and source areas from which water and nutrients entered the stream. Although stream‐dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) both originated from leaching of soluble organic matter, flushing responses between these two DOM components varied because of dynamic shifts of hydrological flow paths and sources that supply the highest concentrations of DOC and DON. High concentrations of stream water nitrate originated from atmospheric sources as well as nitrified sources from catchment soils. We detected nitrification in surficial soils during late snowmelt which affected the nitrate supply that was available to be transported to streams. However, isotopic tracers showed that the majority of nitrate in upslope surficial soil waters after the onset of snowmelt originated from atmospheric sources. A fraction of the atmospheric nitrogen was directly delivered to the stream, and this finding highlights the importance of quick flow pathways during snowmelt events. These findings indicate that interactions among sources, transformations, and hydrologic transport processes must be deciphered to understand why concentrations vary over time and over space as well as to elucidate the direct effects of human activities on nutrient dynamics in upland forest streams.

Continuous magnetic separator and process

DOEpatents

Oder, Robin R.; Jamison, Russell E.

2008-04-22

A continuous magnetic separator and process for separating a slurry comprising magnetic particles into a clarified stream and a thickened stream. The separator has a container with a slurry inlet, an overflow outlet for the discharge of the clarified slurry stream, and an underflow outlet for the discharge of a thickened slurry stream. Magnetic particles in the slurry are attracted to, and slide down, magnetic rods within the container. The slurry is thus separated into magnetic concentrate and clarified slurry. Flow control means can be used to control the ratio of the rate of magnetic concentrate to the rate of clarified slurry. Feed control means can be used to control the rate of slurry feed to the slurry inlet.

Progressing batch hydrolysis process

DOEpatents

Wright, John D.

1986-01-01

A progressive batch hydrolysis process for producing sugar from a lignocellulosic feedstock, comprising passing a stream of dilute acid serially through a plurality of percolation hydrolysis reactors charged with said feedstock, at a flow rate, temperature and pressure sufficient to substantially convert all the cellulose component of the feedstock to glucose; cooling said dilute acid stream containing glucose, after exiting the last percolation hydrolysis reactor, then feeding said dilute acid stream serially through a plurality of prehydrolysis percolation reactors, charged with said feedstock, at a flow rate, temperature and pressure sufficient to substantially convert all the hemicellulose component of said feedstock to glucose; and cooling the dilute acid stream containing glucose after it exits the last prehydrolysis reactor.

Modeling Coupled Physical and Chemical Erosional Processes Using Structure from Motion Reconstruction and Multiphysics Simulation: Applications to Knickpoints in Bedrock Streams in Limestone Caves and on Earth's Surface

NASA Astrophysics Data System (ADS)

Bosch, R.; Ward, D.

2017-12-01

Investigation of erosion rates and processes at knickpoints in surface bedrock streams is an active area of research, involving complex feedbacks in the coupled relationships between dissolution, abrasion, and plucking that have not been sufficiently addressed. Even less research has addressed how these processes operate to propagate knickpoints through cave passages in layered sedimentary rocks, despite these features being common along subsurface streams. In both settings, there is evidence for mechanical and chemical erosion, but in cave passages the different hydrologic and hydraulic regimes, combined with an important role for the dissolution process, affect the relative roles and coupled interactions between these processes, and distinguish them from surface stream knickpoints. Using a novel approach of imaging cave passages using Structure from Motion (SFM), we create 3D geometry meshes to explore these systems using multiphysics simulation, and compare the processes as they occur in caves with those in surface streams. Here we focus on four field sites with actively eroding streambeds that include knickpoints: Upper River Acheron and Devil's Cooling Tub in Mammoth Cave, Kentucky; and two surface streams in Clermont County, Ohio, Avey's Run and Fox Run. SFM 3D reconstructions are built using images exported from 4K video shot at each field location. We demonstrate that SFM is a viable imaging approach for reconstructing cave passages with complex morphologies. We then use these reconstructions to create meshes upon which to run multiphysics simulations using STAR-CCM+. Our approach incorporates multiphase free-surface computational fluid dynamics simulations with sediment transport modeled using discrete element method grains. Physical and chemical properties of the water, bedrock, and sediment enable computation of shear stress, sediment impact forces, and chemical kinetic conditions at the bed surface. Preliminary results prove the efficacy of commercially available multiphysics simulation software for modeling various flow conditions, erosional processes, and their complex coupled interactions in cave passages and in surface stream channels to expand knowledge and understanding of overall cave system development and river profile erosion.

Hydrogeomorphic controls on hyporheic and riparian transport in two headwater mountain streams during base flow recession

NASA Astrophysics Data System (ADS)

Ward, Adam S.; Schmadel, Noah M.; Wondzell, Steven M.; Harman, Ciaran; Gooseff, Michael N.; Singha, Kamini

2016-02-01

Solute transport along riparian and hyporheic flow paths is broadly expected to respond to dynamic hydrologic forcing by streams, aquifers, and hillslopes. However, direct observation of these dynamic responses is lacking, as is the relative control of geologic setting as a control on responses to dynamic hydrologic forcing. We conducted a series of four stream solute tracer injections through base flow recession in each of two watersheds with contrasting valley morphology in the H.J. Andrews Experimental Forest, monitoring tracer concentrations in the stream and in a network of shallow riparian wells in each watershed. We found hyporheic mean arrival time, temporal variance, and fraction of stream water in the bedrock-constrained valley bottom and near large roughness elements in the wider valley bottom were not variable with discharge, suggesting minimal control by hydrologic forcing. Conversely, we observed increases in mean arrival time and temporal variance and decreasing fraction stream water with decreasing discharge near the hillslopes in the wider valley bottom. This may indicate changes in stream discharge and valley bottom hydrology control transport in less constrained locations. We detail five hydrogeomorphic responses to base flow recession to explain observed spatial and temporal patterns in the interactions between streams and their valley bottoms. Models able to account for the transition from geologically dominated processes in the near-stream subsurface to hydrologically dominated processes near the hillslope will be required to predict solute transport and fate in valley bottoms of headwater mountain streams.

The role of DOM in nitrogen processing in streams across arctic regions affected by fire

NASA Astrophysics Data System (ADS)

Rodriguez-Cardona, B.; Schade, J. D.; Holmes, R. M.; Natali, S.; Mann, P. J.; Wymore, A.; Coble, A. A.; Prokishkin, A. S.; Zito, P.; Podgorski, D. C.; Spencer, R. G.; McDowell, W. H.

2017-12-01

In stream ecosystems, inputs of dissolved organic carbon (DOC) have a strong influence on nitrogen (N) processing. Previous studies have demonstrated that increases in DOC concentrations can promote greater N removal in many stream ecosystems. Most of what we know about C and N coupling comes from studies of temperate streams; less is known about this relationship in the Arctic. Streams in Arctic ecosystems are facing rapid changes in climate and disturbance regimes, in particular increasing fire frequencies that are likely to alter biogeochemical cycles. Although fires can lead to increases in NO3 concentrations in streams, the effects of fire on DOC (concentration and composition) have been difficult to generalize. We studied the relationships between DOC and N in two locations; the Central Siberian Plateau, Russia and the Yukon-Kuskokwim (YK) River Delta, Alaska. Streams in both regions show increases in NO3 concentrations after fire, while DOC concentrations decrease in Siberia but increase in streams within the YK-Delta. These patterns in DOC and NO3 create a gradient in DOC and nutrient concentrations, allowing us to study this coupling in a wider Pan-Arctic scope. In order to assess the role of DOC in Arctic N processing, we conducted NO3 and NH4 additions to stream microcosms at the Alaskan site as well as whole-stream additions in Siberia. We hypothesized that nutrient uptake would be high in older burn sites of Siberia and recently burned sites in the YK-Delta, due to greater DOC concentrations and availability. Our results suggest that nitrogen dynamics in the Alaskan sites is strongly responsive to C availability, but is less so in Siberian sites. The potential impacts of permafrost thawing and fires on DOM and nutrient dynamics thus appear to not be consistent across the Arctic suggesting that different regions of the Arctic have unique biogeochemical controls.

Selective catalytic reduction system and process for control of NO.sub.x emissions in a sulfur-containing gas stream

DOEpatents

Sobolevskiy, Anatoly

2015-08-11

An exhaust gas treatment process, apparatus, and system for reducing the concentration of NOx, CO and hydrocarbons in a gas stream, such as an exhaust stream (29), via selective catalytic reduction with ammonia is provided. The process, apparatus and system include a catalytic bed (32) having a reducing only catalyst portion (34) and a downstream reducing-plus-oxidizing portion (36). Each portion (34, 36) includes an amount of tungsten. The reducing-plus-oxidizing catalyst portion (36) advantageously includes a greater amount of tungsten than the reducing catalyst portion (36) to markedly limit ammonia salt formation.

The paradox of cooling streams in a warming world: Regional climate trends do not parallel variable local trends in stream temperature in the Pacific continental United States

USGS Publications Warehouse

Arismendi, Ivan; Johnson, Sherri; Dunham, Jason B.; Haggerty, Roy; Hockman-Wert, David

2012-01-01

Temperature is a fundamentally important driver of ecosystem processes in streams. Recent warming of terrestrial climates around the globe has motivated concern about consequent increases in stream temperature. More specifically, observed trends of increasing air temperature and declining stream flow are widely believed to result in corresponding increases in stream temperature. Here, we examined the evidence for this using long-term stream temperature data from minimally and highly human-impacted sites located across the Pacific continental United States. Based on hypothesized climate impacts, we predicted that we should find warming trends in the maximum, mean and minimum temperatures, as well as increasing variability over time. These predictions were not fully realized. Warming trends were most prevalent in a small subset of locations with longer time series beginning in the 1950s. More recent series of observations (1987-2009) exhibited fewer warming trends and more cooling trends in both minimally and highly human-influenced systems. Trends in variability were much less evident, regardless of the length of time series. Based on these findings, we conclude that our perspective of climate impacts on stream temperatures is clouded considerably by a lack of long-termdata on minimally impacted streams, and biased spatio-temporal representation of existing time series. Overall our results highlight the need to develop more mechanistic, process-based understanding of linkages between climate change, other human impacts and stream temperature, and to deploy sensor networks that will provide better information on trends in stream temperatures in the future.

A secure transmission scheme of streaming media based on the encrypted control message

NASA Astrophysics Data System (ADS)

Li, Bing; Jin, Zhigang; Shu, Yantai; Yu, Li

2007-09-01

As the use of streaming media applications increased dramatically in recent years, streaming media security becomes an important presumption, protecting the privacy. This paper proposes a new encryption scheme in view of characteristics of streaming media and the disadvantage of the living method: encrypt the control message in the streaming media with the high security lever and permute and confuse the data which is non control message according to the corresponding control message. Here the so-called control message refers to the key data of the streaming media, including the streaming media header and the header of the video frame, and the seed key. We encrypt the control message using the public key encryption algorithm which can provide high security lever, such as RSA. At the same time we make use of the seed key to generate key stream, from which the permutation list P responding to GOP (group of picture) is derived. The plain text of the non-control message XORs the key stream and gets the middle cipher text. And then obtained one is permutated according to P. In contrast the decryption process is the inverse process of the above. We have set up a testbed for the above scheme and found our scheme is six to eight times faster than the conventional method. It can be applied not only between PCs but also between handheld devices.

Ambient groundwater flow diminishes nitrogen cycling in streams

NASA Astrophysics Data System (ADS)

Azizian, M.; Grant, S. B.; Rippy, M.; Detwiler, R. L.; Boano, F.; Cook, P. L. M.

2017-12-01

Modeling and experimental studies demonstrate that ambient groundwater reduces hyporheic exchange, but the implications of this observation for stream N-cycling is not yet clear. We utilized a simple process-based model (the Pumping and Streamline Segregation or PASS model) to evaluate N- cycling over two scales of hyporheic exchange (fluvial ripples and riffle-pool sequences), ten ambient groundwater and stream flow scenarios (five gaining and losing conditions and two stream discharges), and three biogeochemical settings (identified based on a principal component analysis of previously published measurements in streams throughout the United States). Model-data comparisons indicate that our model provides realistic estimates for direct denitrification of stream nitrate, but overpredicts nitrification and coupled nitrification-denitrification. Riffle-pool sequences are responsible for most of the N-processing, despite the fact that fluvial ripples generate 3-11 times more hyporheic exchange flux. Across all scenarios, hyporheic exchange flux and the Damkohler Number emerge as primary controls on stream N-cycling; the former regulates trafficking of nutrients and oxygen across the sediment-water interface, while the latter quantifies the relative rates of organic carbon mineralization and advective transport in streambed sediments. Vertical groundwater flux modulates both of these master variables in ways that tend to diminish stream N-cycling. Thus, anthropogenic perturbations of ambient groundwater flows (e.g., by urbanization, agricultural activities, groundwater mining, and/or climate change) may compromise some of the key ecosystem services provided by streams.

Human impacts to mountain streams

NASA Astrophysics Data System (ADS)

Wohl, Ellen

2006-09-01

Mountain streams are here defined as channel networks within mountainous regions of the world. This definition encompasses tremendous diversity of physical and biological conditions, as well as history of land use. Human effects on mountain streams may result from activities undertaken within the stream channel that directly alter channel geometry, the dynamics of water and sediment movement, contaminants in the stream, or aquatic and riparian communities. Examples include channelization, construction of grade-control structures or check dams, removal of beavers, and placer mining. Human effects can also result from activities within the watershed that indirectly affect streams by altering the movement of water, sediment, and contaminants into the channel. Deforestation, cropping, grazing, land drainage, and urbanization are among the land uses that indirectly alter stream processes. An overview of the relative intensity of human impacts to mountain streams is provided by a table summarizing human effects on each of the major mountainous regions with respect to five categories: flow regulation, biotic integrity, water pollution, channel alteration, and land use. This table indicates that very few mountains have streams not at least moderately affected by land use. The least affected mountainous regions are those at very high or very low latitudes, although our scientific ignorance of conditions in low-latitude mountains in particular means that streams in these mountains might be more altered than is widely recognized. Four case studies from northern Sweden (arctic region), Colorado Front Range (semiarid temperate region), Swiss Alps (humid temperate region), and Papua New Guinea (humid tropics) are also used to explore in detail the history and effects on rivers of human activities in mountainous regions. The overview and case studies indicate that mountain streams must be managed with particular attention to upstream/downstream connections, hillslope/channel connections, process domains, physical and ecological roles of disturbance, and stream resilience.

Water Stage Forecasting in Tidal streams during High Water Using EEMD

NASA Astrophysics Data System (ADS)

Chen, Yen-Chang; Kao, Su-Pai; Su, Pei-Yi

2017-04-01

There are so many factors may affect the water stages in tidal streams. Not only the ocean wave but also the stream flow affects the water stage in a tidal stream. During high water, two of the most important factors affecting water stages in tidal streams are flood and tide. However the hydrological processes in tidal streams during high water are nonlinear and nonstationary. Generally the conventional methods used for forecasting water stages in tidal streams are very complicated. It explains the accurately forecasting water stages, especially during high water, in tidal streams is always a difficult task. The study makes used of Ensemble Empirical Model Decomposition (EEMD) to analyze the water stages in tidal streams. One of the advantages of the EEMD is it can be used to analyze the nonlinear and nonstationary data. The EEMD divides the water stage into several intrinsic mode functions (IMFs) and a residual; meanwhile, the physical meaning still remains during the process. By comparing the IMF frequency with tidal frequency, it is possible to identify if the IMF is affected by tides. Then the IMFs is separated into two groups, affected by tide or not by tide. The IMFs in each group are assembled to become a factor. Therefore the water stages in tidal streams are only affected by two factors, tidal factor and flood factor. Finally the regression analysis is used to establish the relationship between the factors of the gaging stations in the tidal stream. The available data during 15 typhoon periods of the Tanshui River whose downstream reach is in estuary area is used to illustrate the accuracy and reliability of the proposed method. The results show that the simple but reliable method is capable of forecasting water stages in tidal streams.

Power-to-Syngas: An Enabling Technology for the Transition of the Energy System?

PubMed

Foit, Severin R; Vinke, Izaak C; de Haart, Lambertus G J; Eichel, Rüdiger-A

2017-05-08

Power-to-X concepts promise a reduction of greenhouse gas emissions simultaneously guaranteeing a safe energy supply even at high share of renewable power generation, thus becoming a cornerstone of a sustainable energy system. Power-to-syngas, that is, the electrochemical conversion of steam and carbon dioxide with the use of renewably generated electricity to syngas for the production of synfuels and high-value chemicals, offers an efficient technology to couple different energy-intense sectors, such as "traffic and transportation" and "chemical industry". Syngas produced by co-electrolysis can thus be regarded as a key-enabling step for a transition of the energy system, which offers additionally features of CO 2 -valorization and closed carbon cycles. Here, we discuss advantages and current limitations of low- and high-temperature co-electrolysis. Advances in both fundamental understanding of the basic reaction schemes and stable high-performance materials are essential to further promote co-electrolysis. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Rationale for continuing R&D in direct coal conversion to produce high quality transportation fuels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Srivastava, R.D.; McIlvried, H.G.; Gray, D.

1995-12-31

For the foreseeable future, liquid hydrocarbon fuels will play a significant role in the transportation sector of both the United States and the world. Factors favoring these fuels include convenience, high energy density, and the vast existing infrastructure for their production and use. At present the U.S. consumes about 26% of the world supply of petroleum, but this situation is expected to change because of declining domestic production and increasing competition for imports from countries with developing economies. A scenario and time frame are developed in which declining world resources will generate a shortfall in petroleum supply that can bemore » allieviated in part by utilizing the abundant domestic coal resource base. One option is direct coal conversion to liquid transportation fuels. Continued R&D in coal conversion technology will results in improved technical readiness that can significantly reduce costs so that synfuels can compete economically in a time frame to address the shortfall.« less

An overview of the Permian (Karoo) coal deposits of southern Africa

NASA Astrophysics Data System (ADS)

Cairncross, B.

2001-08-01

The coal deposits of southern Africa (Botswana, Malawi, Mozambique, Namibia, South Africa, Swaziland, Tanzania, Zambia and Zimbabwe) are reviewed. The coal seams formed during two periods, the Early Permian (Artinskian-Kungurian) and the Late Permian (Ufimian-Kazanian). The coals are associated with non-marine terrestrial clastic sedimentary sequences, most commonly mudrock and sandstones, assigned to the Karoo Supergroup. The Early Permian coals are most commonly sandstone-hosted while the younger coals typically occur interbedded with mudstones. The sediments were deposited in varying tectono-sedimentary basins such as foreland, intracratonic rifts and intercratonic grabens and half-grabens. The depositional environments that produced the coal-bearing successions were primarily deltaic and fluvial, with some minor shoreline and lacustrine settings. Coals vary in rank from high-volatile bituminous to anthracite and characteristically have a relatively high inertinite component, and medium- to high-ash content. In countries where coal is mined, it is used for power generation, coking coal, synfuel generation, gasification and for (local) domestic household consumption.

Summary of synfuel characterization and combustion studies

NASA Technical Reports Server (NTRS)

Schultz, D. F.

1983-01-01

Combustion component research studies aimed at evolving environmentally acceptable approaches for burning coal derived fuels for ground power applications were performed at the NASA Lewis Research Center under a program titled the ""Critical Research and Support Technology Program'' (CRT). The work was funded by the Department of Energy and was performed in four tasks. This report summarizes these tasks which have all been previously reported. In addition some previously unreported data from Task 4 is also presented. The first, Task 1 consisted of a literature survey aimed at determining the properties of synthetic fuels. This was followed by a computer modeling effort, Task 2, to predict the exhaust emissions resulting from burning coal liquids by various combustion techniques such as lean and rich-lean combustion. The computer predictions were then compared to the results of a flame tube rig, Task 3, in which the fuel properties were varied to simulate coal liquids. Two actual SRC 2 coal liquids were tested in this flame tube task.

TECHNICAL MANUAL: A SURVEY OF EQUIPMENT AND METHODS FOR PARTICULATE SAMPLING IN INDUSTRIAL PROCESS STREAMS

EPA Science Inventory

The manual lists and describes the instruments and techniques that are available for measuring the concentration or size distribution of particles suspended in process streams. The standard, official, well established methods are described as well as some experimental methods and...

Concurrent visuomotor behaviour improves form discrimination in a patient with visual form agnosia.

PubMed

Schenk, Thomas; Milner, A David

2006-09-01

It is now well established that the visual brain is divided into two visual streams, the ventral and the dorsal stream. Milner and Goodale have suggested that the ventral stream is dedicated for processing vision for perception and the dorsal stream vision for action [A.D. Milner & M.A. Goodale (1995) The Visual Brain in Action, Oxford University Press, Oxford]. However, it is possible that ongoing processes in the visuomotor stream will nevertheless have an effect on perceptual processes. This possibility was examined in the present study. We have examined the visual form-discrimination performance of the form-agnosic patient D.F. with and without a concurrent visuomotor task, and found that her performance was significantly improved in the former condition. This suggests that the visuomotor behaviour provides cues that enhance her ability to recognize the form of the target object. In control experiments we have ruled out proprioceptive and efferent cues, and therefore propose that D.F. can, to a significant degree, access the object's visuomotor representation in the dorsal stream. Moreover, we show that the grasping-induced perceptual improvement disappears if the target objects only differ with respect to their shape but not their width. This suggests that shape information per se is not used for this grasping task.

Ultrafiltration of thin stillage from conventional and e-mill dry grind processes.

PubMed

Arora, Amit; Dien, Bruce S; Belyea, Ronald L; Wang, Ping; Singh, Vijay; Tumbleson, M E; Rausch, Kent D

2011-05-01

We used ultrafiltration (UF) to evaluate membrane filtration characteristics of thin stillage and determine solids and nutrient compositions of filtered streams. To obtain thin stillage, corn was fermented using laboratory methods. UF experiments were conducted in batch mode under constant temperature and flow rate conditions. Two regenerated cellulose membranes (10 and 100 kDa molecular weight cutoffs) were evaluated with the objective of retaining solids as well as maximizing permeate flux. Optimum pressures for 10 and 100 kDa membranes were 207 and 69 kPa, respectively. Total solids, ash, and neutral detergent fiber contents of input TS streams of dry grind and E-Mill processes were similar; however, fat and protein contents were different (p < 0.05). Retentate obtained from conventional thin stillage fractionation had higher mean total solids contents (27.6% to 27.8%) compared to E-Mill (22.2% to 23.4%). Total solids in retentate streams were found similar to those from commercial evaporators used in industry (25% to 35% total solids). Fat contents of retentate streams ranged from 16.3% to 17.5% for the conventional process. A 2% increment in fat concentration was observed in the E-Mill retentate stream. Thin stillage ash content was reduced 60% in retentate streams.

Bubbling bed catalytic hydropyrolysis process utilizing larger catalyst particles and smaller biomass particles featuring an anti-slugging reactor

DOEpatents

Marker, Terry L; Felix, Larry G; Linck, Martin B; Roberts, Michael J

2014-09-23

This invention relates to a process for thermochemically transforming biomass or other oxygenated feedstocks into high quality liquid hydrocarbon fuels. In particular, a catalytic hydropyrolysis reactor, containing a deep bed of fluidized catalyst particles is utilized to accept particles of biomass or other oxygenated feedstocks that are significantly smaller than the particles of catalyst in the fluidized bed. The reactor features an insert or other structure disposed within the reactor vessel that inhibits slugging of the bed and thereby minimizes attrition of the catalyst. Within the bed, the biomass feedstock is converted into a vapor-phase product, containing hydrocarbon molecules and other process vapors, and an entrained solid char product, which is separated from the vapor stream after the vapor stream has been exhausted from the top of the reactor. When the product vapor stream is cooled to ambient temperatures, a significant proportion of the hydrocarbons in the product vapor stream can be recovered as a liquid stream of hydrophobic hydrocarbons, with properties consistent with those of gasoline, kerosene, and diesel fuel. Separate streams of gasoline, kerosene, and diesel fuel may also be obtained, either via selective condensation of each type of fuel, or via later distillation of the combined hydrocarbon liquid.

Bubbling bed catalytic hydropyrolysis process utilizinig larger catalyst particles and small biomass particles featuring an anti-slugging reactor

DOEpatents

Marker, Terry L.; Felix, Larry G.; Linck, Martin B.; Roberts, Michael J.

2016-12-06

This invention relates to a process for thermochemically transforming biomass or other oxygenated feedstocks into high quality liquid hydrocarbon fuels. In particular, a catalytic hydropyrolysis reactor, containing a deep bed of fluidized catalyst particles is utilized to accept particles of biomass or other oxygenated feedstocks that are significantly smaller than the particles of catalyst in the fluidized bed. The reactor features an insert or other structure disposed within the reactor vessel that inhibits slugging of the bed and thereby minimizes attrition of the catalyst. Within the bed, the biomass feedstock is converted into a vapor-phase product, containing hydrocarbon molecules and other process vapors, and an entrained solid char product, which is separated from the vapor stream after the vapor stream has been exhausted from the top of the reactor. When the product vapor stream is cooled to ambient temperatures, a significant proportion of the hydrocarbons in the product vapor stream can be recovered as a liquid stream of hydrophobic hydrocarbons, with properties consistent with those of gasoline, kerosene, and diesel fuel. Separate streams of gasoline, kerosene, and diesel fuel may also be obtained, either via selective condensation of each type of fuel, or via later distillation of the combined hydrocarbon liquid.

Product-to-parent reversion processes: Stream-hyporheic spiraling increases ecosystem exposure and environmental persistence

NASA Astrophysics Data System (ADS)

Ward, A. S.; Cwiertny, D. M.; Kolodziej, E. P.

2014-12-01

The product-to-parent reversion of metabolites of trenbolone acetate (TBA), a steroidal growth promoter used widely in beef cattle production, was recently observed to occur in environmental waters. The rapid forward reaction is by direct photolysis (i.e., photohydration), with the much slower reversion reaction occurring via dehydration in the dark. The objective of this study is to quantify the potential effect of this newly discovered reversible process on TBA metabolite concentrations and total bioactivity exposure in fluvial systems. Here, we demonstrate increased persistence of TBA metabolites in the stream and hyporheic zone due to the reversion process, increasing chronic and acute exposure to these endocrine-active compounds along a stream. The perpetually dark hyporheic zone is a key location for reversion in the system, ultimately providing a source of the parent compound to the stream and increasing mean in-stream concentration of 17α-trenbolone (17α-TBOH) by 40% of the input concentration under representative fluvial conditions. As such, regulatory frameworks for compounds undergoing product-to-parent reversion will require new approaches for assessing total exposure to bioactive compounds. Further, we demonstrate generalized cases for prediction of exposure for species with product-to-parent reversion in stream-hyporheic systems.

Biological effect of low-head sea lamprey barriers: Designs for extensive surveys and the value of incorporating intensive process-oriented research

USGS Publications Warehouse

Hayes, D.B.; Baylis, J.R.; Carl, L.M.; Dodd, H.R.; Goldstein, J.D.; McLaughlin, R.L.; Noakes, D.L.G.; Porto, L.M.

2003-01-01

Four sampling designs for quantifying the effect of low-head sea lamprey (Petromyzon marinus) barriers on fish communities were evaluated, and the contribution of process-oriented research to the overall confidence of results obtained was discussed. The designs include: (1) sample barrier streams post-construction; (2) sample barrier and reference streams post-construction; (3) sample barrier streams pre- and post-construction; and (4) sample barrier and reference streams pre- and post-construction. In the statistical literature, the principal basis for comparison of sampling designs is generally the precision achieved by each design. In addition to precision, designs should be compared based on the interpretability of results and on the scale to which the results apply. Using data collected in a broad survey of streams with and without sea lamprey barriers, some of the tradeoffs that occur among precision, scale, and interpretability are illustrated. Although circumstances such as funding and availability of pre-construction data may limit which design can be implemented, a pre/post-construction design including barrier and reference streams provides the most meaningful information for use in barrier management decisions. Where it is not feasible to obtain pre-construction data, a design including reference streams is important to maintain the interpretability of results. Regardless of the design used, process-oriented research provides a framework for interpreting results obtained in broad surveys. As such, information from both extensive surveys and intensive process-oriented research provides the best basis for fishery management actions, and gives researchers and managers the most confidence in the conclusions reached regarding the effects of sea lamprey barriers.

Perched groundwater-surface interactions and their consequences in stream flow generation in a semi-arid headwater catchment

NASA Astrophysics Data System (ADS)

Molenat, Jerome; Bouteffeha, Maroua; Raclot, Damien; Bouhlila, Rachida

2013-04-01

In semi-arid headwater catchment, it is usually admitted that stream flow comes predominantly from Hortonian overland flow (infiltration excess overland flow). Consequently, subsurface flow processes, and especially perched or shallow groundwater flow, have not been studied extensively. Here we made the assumption that perched groundwater flow could play a significant role in stream flow generation in semi-arid catchment. To test this assumption, we analyzed stream flow time series of a headwater catchment in the Tunisian Cap Bon region and quantified the flow fraction coming from groundwater discharge and that from overland flow. Furthermore, the dynamics of the perched groundwater was analyzed, by focusing on the different perched groundwater-surface interaction processes : diffuse and local infiltration, diffuse exfiltration, and direct groundwater discharge to the stream channel. This work is based on the 2.6 km² Kamech catchment (Tunisia), which belongs to the long term Mediterranean hydrological observatory OMERE (Voltz and Albergel, 2002). Results show that even though Hortonian overland flow was the main hydrological process governing the stream flow generation, groundwater discharge contribution to the stream channel annually accounted for from 10% to 20 % depending on the year. Furthermore, at some periods, rising of groundwater table to the soil surface in bottom land areas provided evidences of the occurrence of saturation excess overland flow processes during some storm events. Reference Voltz , M. and Albergel , J., 2002. OMERE : Observatoire Méditerranéen de l'Environnement Rural et de l'Eau - Impact des actions anthropiques sur les transferts de masse dans les hydrosystèmes méditerranéens ruraux. Proposition d'Observatoire de Recherche en Environnement, Ministère de la Recherche.

Limitations and implications of stream classification

USGS Publications Warehouse

Juracek, K.E.; Fitzpatrick, F.A.

2003-01-01

Stream classifications that are based on channel form, such as the Rosgen Level II classification, are useful tools for the physical description and grouping of streams and for providing a means of communication for stream studies involving scientists and (or) managers with different backgrounds. The Level II classification also is used as a tool to assess stream stability, infer geomorphic processes, predict future geomorphic response, and guide stream restoration or rehabilitation activities. The use of the Level II classification for these additional purposes is evaluated in this paper. Several examples are described to illustrate the limitations and management implications of the Level II classification. Limitations include: (1) time dependence, (2) uncertain applicability across physical environments, (3) difficulty in identification of a true equilibrium condition, (4) potential for incorrect determination of bankfull elevation, and (5) uncertain process significance of classification criteria. Implications of using stream classifications based on channel form, such as Rosgen's, include: (1) acceptance of the limitations, (2) acceptance of the risk of classifying streams incorrectly, and (3) classification results may be used inappropriately. It is concluded that use of the Level II classification for purposes beyond description and communication is not appropriate. Research needs are identified that, if addressed, may help improve the usefulness of the Level II classification.

Quantifying nutrient sources in an upland catchment using multiple chemical and isotopic tracers

NASA Astrophysics Data System (ADS)

Sebestyen, S. D.; Boyer, E. W.; Shanley, J. B.; Doctor, D. H.; Kendall, C.; Aiken, G. R.

2006-12-01

To explore processes that control the temporal variation of nutrients in surface waters, we measured multiple environmental tracers at the Sleepers River Research Watershed, an upland catchment in northeastern Vermont, USA. Using a set of high-frequency stream water samples, we quantified the variation of nutrients over a range of stream flow conditions with chemical and isotopic tracers of water, nitrate, and dissolved organic carbon (DOC). Stream water concentrations of nitrogen (predominantly in the forms of nitrate and dissolved organic nitrogen) and DOC reflected mixing of water contributed from distinct sources in the forested landscape. Water isotopic signatures and end-member mixing analysis revealed when solutes entered the stream from these sources and that the sources were linked to the stream by preferential shallow subsurface and overland flow paths. Results from the tracers indicated that freshly-leached, terrestrial organic matter was the overwhelming source of high DOC concentrations in stream water. In contrast, in this region where atmospheric nitrogen deposition is chronically elevated, the highest concentrations of stream nitrate were attributable to atmospheric sources that were transported via melting snow and rain fall. These findings are consistent with a conceptual model of the landscape in which coupled hydrological and biogeochemical processes interact to control stream solute variability over time.

A quantitative analysis of hydraulic interaction processes in stream-aquifer systems

DOE PAGES

Wang, Wenke; Dai, Zhenxue; Zhao, Yaqian; ...

2016-01-28

The hydraulic relationship between the stream and aquifer can be altered from hydraulic connection to disconnection when the pumping rate exceeds the maximum seepage flux of the streambed. This study proposes to quantitatively analyze the physical processes of stream-aquifer systems from connection to disconnection. A free water table equation is adopted to clarify under what conditions a stream starts to separate hydraulically from an aquifer. Both the theoretical analysis and laboratory tests have demonstrated that the hydraulic connectedness of the stream-aquifer system can reach a critical disconnection state when the horizontal hydraulic gradient at the free water surface is equalmore » to zero and the vertical is equal to 1. A boundary-value problem for movement of the critical point of disconnection is established for an analytical solution of the inverted water table movement beneath the stream. The result indicates that the maximum distance or thickness of the inverted water table is equal to the water depth in the stream, and at a steady state of disconnection, the maximum hydraulic gradient at the streambed center is 2. In conclusion, this study helps us to understand the hydraulic phenomena of water flow near streams and accurately assess surface water and groundwater resources.« less

Distinct Contributions of the Magnocellular and Parvocellular Visual Streams to Perceptual Selection

PubMed Central

Denison, Rachel N.; Silver, Michael A.

2014-01-01

During binocular rivalry, conflicting images presented to the two eyes compete for perceptual dominance, but the neural basis of this competition is disputed. In interocular switch (IOS) rivalry, rival images periodically exchanged between the two eyes generate one of two types of perceptual alternation: 1) a fast, regular alternation between the images that is time-locked to the stimulus switches and has been proposed to arise from competition at lower levels of the visual processing hierarchy, or 2) a slow, irregular alternation spanning multiple stimulus switches that has been associated with higher levels of the visual system. The existence of these two types of perceptual alternation has been influential in establishing the view that rivalry may be resolved at multiple hierarchical levels of the visual system. We varied the spatial, temporal, and luminance properties of IOS rivalry gratings and found, instead, an association between fast, regular perceptual alternations and processing by the magnocellular stream and between slow, irregular alternations and processing by the parvocellular stream. The magnocellular and parvocellular streams are two early visual pathways that are specialized for the processing of motion and form, respectively. These results provide a new framework for understanding the neural substrates of binocular rivalry that emphasizes the importance of parallel visual processing streams, and not only hierarchical organization, in the perceptual resolution of ambiguities in the visual environment. PMID:21861685

Is the diet of a typical shredder related to the physical habitat of headwater streams in the Brazilian Cerrado?

EPA Science Inventory

Macroinvertebrates are important for processing leaf detritus in temperate streams, but studies about their role in tropical streams are scarce and often present conflicting results. We assessed the diet of Phylloicus (Trichoptera: Calamoceratidae) larvae, that is generally class...

THE EFFECTS OF ECOSYSTEM RESTORATION ON NITROGEN PROCESSING IN AN URBAN MID-ATLANTIC PIEDMONT STREAM

EPA Science Inventory

Elevated nitrate levels in streams and groundwater pose human and ecological threats. The US EPA, USGS, Institute of Ecosystem Studies, and Baltimore County Dept. of Environmental Protection are collaborating on a multi-year study of the impacts of stream restoration on nitrogen...

Nitrogen Uptake and Denitrification in Restored and Unrestored Streams in Urban Maryland, USA

EPA Science Inventory

There is growing interest in rates of nitrate uptake and denitrification in restored streams to better understand the effects of restoration on nitrogen processing. This study quantified nitrate uptake in 2 restored and 2 unrestored streams in Baltimore, Maryland, U.S.A. using n...

By land or by stream? contribution of constrained dispersal by adult caddisflies to diversity loss from urban headwaters

EPA Science Inventory

The adult stage of streams insects is responsible for important life-cycle processes such as dispersal and reproduction, yet interactions of adult stream insects with terrestrial landscapes are rarely studied. This trend is especially problematic in urbanized landscapes where th...

New methods for modeling stream temperature using high resolution LiDAR, solar radiation analysis and flow accumulated values

EPA Science Inventory

In-stream temperature directly effects a variety of biotic organisms, communities and processes. Changes in stream temperature can render formally suitable habitat unsuitable for aquatic organisms, particularly native cold water species that are not able to adjust. In order to an...

Effects of hemlock mortality on streams in the southern Appalachian mountains

Treesearch

J.R. Webster; K. Morkeski; C.A. Wojculewski; B.R. Niederlehner; E.F. Benfield; K.J. Elliott

2012-01-01

The death of eastern hemlock (Tsuga canadensis) trees in response to infestation by the introduced hemlock woolly adelgid (Adelges tsugae)may affect ecosystem processes and structure of streams. Prior to hemlock mortality,we documented the condition so feight small streams and their associated riparian forests within the...

Low NO[sub x], cogeneration process and system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bell, R.D.

1993-07-06

A process is described for low NO[sub x] cogeneration to produce electricity and useful heat, which comprises: providing fuel and oxygen to an internal combustion engine connected to drive an electric generator, to thereby generate electricity; recovering from said engine an exhaust stream including elevated NO[sub x] levels and combined oxygen; adding to said exhaust stream sufficient fuel to create a fuel-rich mixture, the quantity of fuel being sufficient to react with the available oxygen and reduce the NO[sub x], in said exhaust stream; providing said fuel-enriched exhaust stream to a thermal reactor and reacting therein said fuel, NO[sub x]more » and available oxygen, to provide a heated oxygen-depleted stream; cooling said oxygen-depleted stream by passing same through a first heat exchanger; adding conversion oxygen to said cooled stream from said heat exchanger, and passing the cooled oxygen-augmented stream over a first catalyst bed operated at a temperature of about 750 to 1,250 F under overall reducing conditions, the quantity of conversion oxygen added being in stoichiometric excess of the amount of NO[sub x], but less than the amount of combustibles; whereby the NO[sub x] is first oxidized to NO[sub 2], and then the NO[sub 2] is reduced by the excess combustibles; cooling said stream from said first catalyst bed to a temperature of about 450 to 650 F by passing said stream through a second heat exchanger; adding air to the resulting cooled stream to produce a further cooled stream at a temperature of about 400 to 600 F, and having a stoichiometric excess of oxygen; and passing said stream having said stoichiometric excess of oxygen over an oxidizing catalyst bed at said temperature of 400 to 600 F to oxidize remaining excess combustibles, to thereby provide an effluent stream having environmentally safe characteristics.« less

Process for CO.sub.2 capture using zeolites from high pressure and moderate temperature gas streams

DOEpatents

Siriwardane, Ranjani V [Morgantown, WV; Stevens, Robert W [Morgantown, WV

2012-03-06

A method for separating CO.sub.2 from a gas stream comprised of CO.sub.2 and other gaseous constituents using a zeolite sorbent in a swing-adsorption process, producing a high temperature CO.sub.2 stream at a higher CO.sub.2 pressure than the input gas stream. The method utilizes CO.sub.2 desorption in a CO.sub.2 atmosphere and effectively integrates heat transfers for optimizes overall efficiency. H.sub.2O adsorption does not preclude effective operation of the sorbent. The cycle may be incorporated in an IGCC for efficient pre-combustion CO.sub.2 capture. A particular application operates on shifted syngas at a temperature exceeding 200.degree. C. and produces a dry CO.sub.2 stream at low temperature and high CO.sub.2 pressure, greatly reducing any compression energy requirements which may be subsequently required.

Chapter 6: Temperature

USGS Publications Warehouse

Jones, Leslie A.; Muhlfeld, Clint C.; Hauer, F. Richard; F. Richard Hauer,; Lamberti, G.A.

2017-01-01

Stream temperature has direct and indirect effects on stream ecology and is critical in determining both abiotic and biotic system responses across a hierarchy of spatial and temporal scales. Temperature variation is primarily driven by solar radiation, while landscape topography, geology, and stream reach scale ecosystem processes contribute to local variability. Spatiotemporal heterogeneity in freshwater ecosystems influences habitat distributions, physiological functions, and phenology of all aquatic organisms. In this chapter we provide an overview of methods for monitoring stream temperature, characterization of thermal profiles, and modeling approaches to stream temperature prediction. Recent advances in temperature monitoring allow for more comprehensive studies of the underlying processes influencing annual variation of temperatures and how thermal variability may impact aquatic organisms at individual, population, and community based scales. Likewise, the development of spatially explicit predictive models provide a framework for simulating natural and anthropogenic effects on thermal regimes which is integral for sustainable management of freshwater systems.

Process and apparatus for producing ultrafine explosive particles

DOEpatents

McGowan, Michael J.

1992-10-20

A method and an improved eductor apparatus for producing ultrafine explosive particles is disclosed. The explosive particles, which when incorporated into a binder system, have the ability to propagate in thin sheets, and have very low impact sensitivity and very high propagation sensitivity. A stream of a solution of the explosive dissolved in a solvent is thoroughly mixed with a stream of an inert nonsolvent by obtaining nonlaminar flow of the streams by applying pressure against the flow of the nonsolvent stream, to thereby diverge the stream as it contacts the explosive solution, and violently agitating the combined stream to rapidly precipitate the explosive particles from the solution in the form of generally spheroidal, ultrafine particles. The two streams are injected coaxially through continuous, concentric orifices of a nozzle into a mixing chamber. Preferably, the nonsolvent stream is injected centrally of the explosive solution stream. The explosive solution stream is injected downstream of and surrounds the nonsolvent solution stream for a substantial distance prior to being ejected into the mixing chamber.

Incorporation of the equilibrium temperature approach in a Soil and Water Assessment Tool hydroclimatological stream temperature model

NASA Astrophysics Data System (ADS)

Du, Xinzhong; Shrestha, Narayan Kumar; Ficklin, Darren L.; Wang, Junye

2018-04-01

Stream temperature is an important indicator for biodiversity and sustainability in aquatic ecosystems. The stream temperature model currently in the Soil and Water Assessment Tool (SWAT) only considers the impact of air temperature on stream temperature, while the hydroclimatological stream temperature model developed within the SWAT model considers hydrology and the impact of air temperature in simulating the water-air heat transfer process. In this study, we modified the hydroclimatological model by including the equilibrium temperature approach to model heat transfer processes at the water-air interface, which reflects the influences of air temperature, solar radiation, wind speed and streamflow conditions on the heat transfer process. The thermal capacity of the streamflow is modeled by the variation of the stream water depth. An advantage of this equilibrium temperature model is the simple parameterization, with only two parameters added to model the heat transfer processes. The equilibrium temperature model proposed in this study is applied and tested in the Athabasca River basin (ARB) in Alberta, Canada. The model is calibrated and validated at five stations throughout different parts of the ARB, where close to monthly samplings of stream temperatures are available. The results indicate that the equilibrium temperature model proposed in this study provided better and more consistent performances for the different regions of the ARB with the values of the Nash-Sutcliffe Efficiency coefficient (NSE) greater than those of the original SWAT model and the hydroclimatological model. To test the model performance for different hydrological and environmental conditions, the equilibrium temperature model was also applied to the North Fork Tolt River Watershed in Washington, United States. The results indicate a reasonable simulation of stream temperature using the model proposed in this study, with minimum relative error values compared to the other two models. However, the NSE values were lower than those of the hydroclimatological model, indicating that more model verification needs to be done. The equilibrium temperature model uses existing SWAT meteorological data as input, can be calibrated using fewer parameters and less effort and has an overall better performance in stream temperature simulation. Thus, it can be used as an effective tool for predicting the changes in stream temperature regimes under varying hydrological and meteorological conditions. In addition, the impact of the stream temperature simulations on chemical reaction rates and concentrations was tested. The results indicate that the improved performance of the stream temperature simulation could significantly affect chemical reaction rates and the simulated concentrations, and the equilibrium temperature model could be a potential tool to model stream temperature in water quality simulations.

The Blurred Line between Form and Process: A Comparison of Stream Channel Classification Frameworks

PubMed Central

Kasprak, Alan; Hough-Snee, Nate

2016-01-01

Stream classification provides a means to understand the diversity and distribution of channels and floodplains that occur across a landscape while identifying links between geomorphic form and process. Accordingly, stream classification is frequently employed as a watershed planning, management, and restoration tool. At the same time, there has been intense debate and criticism of particular frameworks, on the grounds that these frameworks classify stream reaches based largely on their physical form, rather than direct measurements of their component hydrogeomorphic processes. Despite this debate surrounding stream classifications, and their ongoing use in watershed management, direct comparisons of channel classification frameworks are rare. Here we implement four stream classification frameworks and explore the degree to which each make inferences about hydrogeomorphic process from channel form within the Middle Fork John Day Basin, a watershed of high conservation interest within the Columbia River Basin, U.S.A. We compare the results of the River Styles Framework, Natural Channel Classification, Rosgen Classification System, and a channel form-based statistical classification at 33 field-monitored sites. We found that the four frameworks consistently classified reach types into similar groups based on each reach or segment’s dominant hydrogeomorphic elements. Where classified channel types diverged, differences could be attributed to the (a) spatial scale of input data used, (b) the requisite metrics and their order in completing a framework’s decision tree and/or, (c) whether the framework attempts to classify current or historic channel form. Divergence in framework agreement was also observed at reaches where channel planform was decoupled from valley setting. Overall, the relative agreement between frameworks indicates that criticism of individual classifications for their use of form in grouping stream channels may be overstated. These form-based criticisms may also ignore the geomorphic tenet that channel form reflects formative hydrogeomorphic processes across a given landscape. PMID:26982076

Using δ15N of Chironomidae as an index of nitrogen sources and processing within watersheds as part of EPA's National Aquatic Resource Surveys

NASA Astrophysics Data System (ADS)

Brooks, J. R.; Compton, J.; Herlihy, A.; Sobota, D. J.; Stoddard, J.; Weber, M.

2014-12-01

Nitrogen (N) removal in watersheds is an important regulating ecosystem service that can help reduce N pollution in the nation's waterways. However, processes that remove N such as denitrification are generally determined at point locations. Measures that integrate N processing within watersheds and over time would be particularly useful for assessing the degree of this vital service. Because most N removal processes isotopically enrich the N remaining, δ15N from basal food-chain organisms in aquatic ecosystems can provide information on watershed N processing. As part of EPA's National Aquatic Resource Surveys (NARS), we measured δ15N of Chironomidae in lakes, rivers and streams because these larval aquatic insects were found in abundance in almost every lake and stream in the U.S. Using information on nitrogen loading to the watershed, and total N concentrations within the water, we assessed when elevated chironomid δ15N would indicate N removal rather than possible enriched sources of N. Chironomid δ15N values ranged from -4 to +20 ‰, and were higher in rivers and streams than in lakes (median = 7.6 ‰ vs. 4.8 ‰, respectively), indicating that N was processed to a greater degree in lotic chironomids than in lentic ones. For both, δ15N increased with watershed-level agricultural land cover and N loading, and decreased as precipitation increased. In rivers and streams with high synthetic N loading, we found lower N concentrations in streams with higher chironomid δ15N values, suggesting greater N removal. At low levels of synthetic N loading, the pattern reversed, and streams with enriched chironomid δ15N had higher N concentrations, suggesting enriched sources such as manure or sewage. Our results indicate that chironomid δ15N values can provide valuable information about watershed-level N inputs and processing for national water quality monitoring efforts.

The importance of the riparian zone and in-stream processes in nitrate attenuation in undisturbed and agricultural watersheds – a review of the scientific literature

USGS Publications Warehouse

Ranalli, Anthony J.; Macalady, Donald L.

2010-01-01

We reviewed published studies from primarily glaciated regions in the United States, Canada, and Europe of the (1) transport of nitrate from terrestrial ecosystems to aquatic ecosystems, (2) attenuation of nitrate in the riparian zone of undisturbed and agricultural watersheds, (3) processes contributing to nitrate attenuation in riparian zones, (4) variation in the attenuation of nitrate in the riparian zone, and (5) importance of in-stream and hyporheic processes for nitrate attenuation in the stream channel. Our objectives were to synthesize the results of these studies and suggest methodologies to (1) monitor regional trends in nitrate concentration in undisturbed 1st order watersheds and (2) reduce nitrate loads in streams draining agricultural watersheds. Our review reveals that undisturbed headwater watersheds have been shown to be very retentive of nitrogen, but the importance of biogeochemical and hydrological riparian zone processes in retaining nitrogen in these watersheds has not been demonstrated as it has for agricultural watersheds. An understanding of the role of the riparian zone in nitrate attenuation in undisturbed watersheds is crucial because these watersheds are increasingly subject to stressors, such as changes in land use and climate, wildfire, and increases in atmospheric nitrogen deposition. In general, understanding processes controlling the concentration and flux of nitrate is critical to identifying and mapping the vulnerability of watersheds to water quality changes due to a variety of stressors. In undisturbed and agricultural watersheds we propose that understanding the importance of riparian zone processes in 2nd order and larger watersheds is critical. Research is needed that addresses the relative importance of how the following sources of nitrate along any given stream reach might change as watersheds increase in size and with flow: (1) inputs upstream from the reach, (2) tributary inflow, (3) water derived from the riparian zone, (4) groundwater from outside the riparian zone (intermediate or regional sources), and (5) in-stream (hyporheic) processes.

Method of dye removal for the textile industry

DOEpatents

Stone, Mark L.

2000-01-01

The invention comprises a method of processing a waste stream containing dyes, such as a dye bath used in the textile industry. The invention comprises using an inorganic-based polymer, such as polyphosphazene, to separate dyes and/or other chemicals from the waste stream. Membranes comprising polyphosphazene have the chemical and thermal stability to survive the harsh, high temperature environment of dye waste streams, and have been shown to completely separate dyes from the waste stream. Several polyphosplhazene membranes having a variety of organic substituent have been shown effective in removing color from waste streams.

Rangeland Riparian Systems

Treesearch

Wayne Elmore

1989-01-01

The management and recovery of degraded riparian systems is a major conservation issue. Presently there are many grazing management strategies being applied based on the name of the technique with little incorporation of basic stream processes. Managers must understand the exact workings of grazing strategies and the individual processes of each stream before...

Disc valve for sampling erosive process streams

DOEpatents

Mrochek, J.E.; Dinsmore, S.R.; Chandler, E.W.

1984-08-16

This is a patent for a disc-type, four-port sampling valve for service with erosive high temperature process streams. Inserts and liners of ..cap alpha..-silicon carbide respectively, in the faceplates and in the sampling cavities, limit erosion while providing lubricity for a smooth and precise operation. 1 fig.

On the mechanisms leading to orphan meteoroid streams

NASA Astrophysics Data System (ADS)

Vaubaillon, J.; Lamy, P.; Jorda, L.

2006-08-01

We analyse several mechanisms capable of creating orphan meteoroid streams (OMSs) for which a parent has not been identified. OMSs have been observed as meteor showers since the XIXth century and by the IRAS satellite in the 1980s. We find that the process of close encounters with giant planets (particularly Jupiter) is the most efficient mechanism to create them: only a limited section of the stream is perturbed and follows the parent body on its new orbit, while the majority of the meteoroids remain in their pre-encounter orbit or in an intermediate state, breaking the link with their parent body. Cometary non-gravitational forces can also contribute to the process since they cause the comet to drift away from its stream. However, they are not sufficient by themselves to produce an OMS. Resonances can either split or confine a stream over a long time (>1000 yr). Some meteoroid streams may look like OMSs since their parent comet is dormant or not observable (e.g. long period). Even if new techniques succeed in linking minor objects to meteoroid streams, OMSs will still exist simply because cometary nuclei are subject to complete disruption leading to their disappearance.

In-camera video-stream processing for bandwidth reduction in web inspection

NASA Astrophysics Data System (ADS)

Jullien, Graham A.; Li, QiuPing; Hajimowlana, S. Hossain; Morvay, J.; Conflitti, D.; Roberts, James W.; Doody, Brian C.

1996-02-01

Automated machine vision systems are now widely used for industrial inspection tasks where video-stream data information is taken in by the camera and then sent out to the inspection system for future processing. In this paper we describe a prototype system for on-line programming of arbitrary real-time video data stream bandwidth reduction algorithms; the output of the camera only contains information that has to be further processed by a host computer. The processing system is built into a DALSA CCD camera and uses a microcontroller interface to download bit-stream data to a XILINXTM FPGA. The FPGA is directly connected to the video data-stream and outputs data to a low bandwidth output bus. The camera communicates to a host computer via an RS-232 link to the microcontroller. Static memory is used to both generate a FIFO interface for buffering defect burst data, and for off-line examination of defect detection data. In addition to providing arbitrary FPGA architectures, the internal program of the microcontroller can also be changed via the host computer and a ROM monitor. This paper describes a prototype system board, mounted inside a DALSA camera, and discusses some of the algorithms currently being implemented for web inspection applications.

Stream processing health card application.

PubMed

Polat, Seda; Gündem, Taflan Imre

2012-10-01

In this paper, we propose a data stream management system embedded to a smart card for handling and storing user specific summaries of streaming data coming from medical sensor measurements and/or other medical measurements. The data stream management system that we propose for a health card can handle the stream data rates of commonly known medical devices and sensors. It incorporates a type of context awareness feature that acts according to user specific information. The proposed system is cheap and provides security for private data by enhancing the capabilities of smart health cards. The stream data management system is tested on a real smart card using both synthetic and real data.

Multi-scale interactions affecting transport, storage, and processing of solutes and sediments in stream corridors (Invited)

NASA Astrophysics Data System (ADS)

Harvey, J. W.; Packman, A. I.

2010-12-01

Surface water and groundwater flow interact with the channel geomorphology and sediments in ways that determine how material is transported, stored, and transformed in stream corridors. Solute and sediment transport affect important ecological processes such as carbon and nutrient dynamics and stream metabolism, processes that are fundamental to stream health and function. Many individual mechanisms of transport and storage of solute and sediment have been studied, including surface water exchange between the main channel and side pools, hyporheic flow through shallow and deep subsurface flow paths, and sediment transport during both baseflow and floods. A significant challenge arises from non-linear and scale-dependent transport resulting from natural, fractal fluvial topography and associated broad, multi-scale hydrologic interactions. Connections between processes and linkages across scales are not well understood, imposing significant limitations on system predictability. The whole-stream tracer experimental approach is popular because of the spatial averaging of heterogeneous processes; however the tracer results, implemented alone and analyzed using typical models, cannot usually predict transport beyond the very specific conditions of the experiment. Furthermore, the results of whole stream tracer experiments tend to be biased due to unavoidable limitations associated with sampling frequency, measurement sensitivity, and experiment duration. We recommend that whole-stream tracer additions be augmented with hydraulic and topographic measurements and also with additional tracer measurements made directly in storage zones. We present examples of measurements that encompass interactions across spatial and temporal scales and models that are transferable to a wide range of flow and geomorphic conditions. These results show how the competitive effects between the different forces driving hyporheic flow, operating at different spatial scales, creates a situation where hyporheic fluxes cannot be accurately estimated without considering multi-scale effects. Our modeling captures the dominance of small-scale features such as bedforms that drive the majority of hyporheic flow, but it also captures how hyporheic flow is substantially modified by relatively small changes in streamflow or groundwater flow. The additional field measurements add sensitivity and power to whole stream tracer additions by improving resolution of the relative importance of storage at different scales (e.g. bar-scale versus bedform-scale). This information is critical in identifying hot spots where important biogeochemical reactions occur. In summary, interpreting multi-scale interactions in streams requires models that are physically based and that incorporate non-linear process dynamics. Such models can take advantage of increasingly comprehensive field data to integrate transport processes across spatially variable flow and geomorphic conditions. The most useful field and modeling approaches will be those that are simple enough to be easily implemented by users from various disciplines but comprehensive enough to produce meaningful predictions for a wide range of flow and geomorphic scenarios. This capability is needed to support improved strategies for protecting stream ecological health in the face of accelerating land use and climate change.

Ordered Backward XPath Axis Processing against XML Streams

NASA Astrophysics Data System (ADS)

Nizar M., Abdul; Kumar, P. Sreenivasa

Processing of backward XPath axes against XML streams is challenging for two reasons: (i) Data is not cached for future access. (ii) Query contains steps specifying navigation to the data that already passed by. While there are some attempts to process parent and ancestor axes, there are very few proposals to process ordered backward axes namely, preceding and preceding-sibling. For ordered backward axis processing, the algorithm, in addition to overcoming the limitations on data availability, has to take care of ordering constraints imposed by these axes. In this paper, we show how backward ordered axes can be effectively represented using forward constraints. We then discuss an algorithm for XML stream processing of XPath expressions containing ordered backward axes. The algorithm uses a layered cache structure to systematically accumulate query results. Our experiments show that the new algorithm gains remarkable speed up over the existing algorithm without compromising on bufferspace requirement.

Generation of useful energy from process fluids using the biphase turbine

NASA Astrophysics Data System (ADS)

Helgeson, N. L.

1981-01-01

The six largest energy consuming industries in the United States were surveyed to determine the energy savings that could result from applying the Biphase turbine to industrial process streams. A national potential energy savings of 58 million barrels of oil per year (technical market) was identified. This energy is recoverable from flashing gas liquid process streams and is separate and distinct from exhaust gas waste heat recovery. The industries surveyed in this program were the petroleum chemical, primary metals, paper and pulp, stone-clay-glass, and food. It was required to determine the applicability of the Biphase turbine to flashing operations connected with process streams, to determine the energy changes associated with these flashes if carried out in a Biphase turbine, and to determine the suitability (technical and economical feasibility) of applying the Biphase turbine to these processes.

Interaction between dorsal and ventral processing streams: where, when and how?

PubMed

Cloutman, Lauren L

2013-11-01

The execution of complex visual, auditory, and linguistic behaviors requires a dynamic interplay between spatial ('where/how') and non-spatial ('what') information processed along the dorsal and ventral processing streams. However, while it is acknowledged that there must be some degree of interaction between the two processing networks, how they interact, both anatomically and functionally, is a question which remains little explored. The current review examines the anatomical, temporal, and behavioral evidence regarding three potential models of dual stream interaction: (1) computations along the two pathways proceed independently and in parallel, reintegrating within shared target brain regions; (2) processing along the separate pathways is modulated by the existence of recurrent feedback loops; and (3) information is transferred directly between the two pathways at multiple stages and locations along their trajectories. Copyright © 2012 Elsevier Inc. All rights reserved.

Modelling the influence of elevation and snow regime on winter stream temperature in the rain-on-snow zone

NASA Astrophysics Data System (ADS)

Leach, J.; Moore, D.

2015-12-01

Winter stream temperature of coastal mountain catchments influences fish growth and development. Transient snow cover and advection associated with lateral throughflow inputs are dominant controls on stream thermal regimes in these regions. Existing stream temperature models lack the ability to properly simulate these processes. Therefore, we developed and evaluated a conceptual-parametric catchment-scale stream temperature model that includes the role of transient snow cover and lateral advection associated with throughflow. The model provided reasonable estimates of observed stream temperature at three test catchments. We used the model to simulate winter stream temperature for virtual catchments located at different elevations within the rain-on-snow zone. The modelling exercise examined stream temperature response associated with interactions between elevation, snow regime, and changes in air temperature. Modelling results highlight that the sensitivity of winter stream temperature response to changes in climate may be dependent on catchment elevation and landscape position.

Coated armor system and process for making the same

DOEpatents

Chu, Henry S.; Lillo, Thomas M.; McHugh, Kevin M.

2010-11-23

An armor system and method involves providing a core material and a stream of atomized coating material that comprises a liquid fraction and a solid fraction. An initial layer is deposited on the core material by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is less than the liquid fraction of the stream of atomized coating material on a weight basis. An outer layer is then deposited on the initial layer by positioning the core material in the stream of atomized coating material wherein the solid fraction of the stream of atomized coating material is greater than the liquid fraction of the stream of atomized coating material on a weight basis.

Monitoring stream temperatures—A guide for non-specialists

USGS Publications Warehouse

Heck, Michael P.; Schultz, Luke D.; Hockman-Wert, David; Dinger, Eric C.; Dunham, Jason B.

2018-04-19

Executive SummaryWater temperature influences most physical and biological processes in streams, and along with streamflows is a major driver of ecosystem processes. Collecting data to measure water temperature is therefore imperative, and relatively straightforward. Several protocols exist for collecting stream temperature data, but these are frequently directed towards specialists. This document was developed to address the need for a protocol intended for non-specialists (non-aquatic) staff. It provides specific step-by-step procedures on (1) how to launch data loggers, (2) check the factory calibration of data loggers prior to field use, (3) how to install data loggers in streams for year-round monitoring, (4) how to download and retrieve data loggers from the field, and (5) how to input project data into organizational databases.

Performance analysis of sliding window filtering of two dimensional signals based on stream data processing systems

NASA Astrophysics Data System (ADS)

Kazanskiy, Nikolay; Protsenko, Vladimir; Serafimovich, Pavel

2016-03-01

This research article contains an experiment with implementation of image filtering task in Apache Storm and IBM InfoSphere Streams stream data processing systems. The aim of presented research is to show that new technologies could be effectively used for sliding window filtering of image sequences. The analysis of execution was focused on two parameters: throughput and memory consumption. Profiling was performed on CentOS operating systems running on two virtual machines for each system. The experiment results showed that IBM InfoSphere Streams has about 1.5 to 13.5 times lower memory footprint than Apache Storm, but could be about 2.0 to 2.5 slower on a real hardware.

Electrowinning apparatus and process

DOEpatents

Buschmann, Wayne E [Boulder, CO

2012-06-19

Apparatus and processes are disclosed for electrowinning metal from a fluid stream. A representative apparatus comprises at least one spouted bed reactor wherein each said reactor includes an anolyte chamber comprising an anode and configured for containing an anolyte, a catholyte chamber comprising a current collector and configured for containing a particulate cathode bed and a flowing stream of an electrically conductive metal-containing fluid, and a membrane separating said anolyte chamber and said catholyte chamber, an inlet for an electrically conductive metal-containing fluid stream; and a particle bed churning device configured for spouting particle bed particles in the catholyte chamber independently of the flow of said metal-containing fluid stream. In operation, reduced heavy metals or their oxides are recovered from the cathode particles.

Separation of uranium from technetium in recovery of spent nuclear fuel

DOEpatents

Pruett, D.J.; McTaggart, D.R.

1983-08-31

Uranium and technetium in the product stream of the Purex process for recovery of uranium in spent nuclear fuel are separated by (1) contacting the aqueous Purex product stream with hydrazine to reduce Tc/sup +7/ therein to a reduced species, and (2) contacting said aqueous stream with an organic phase containing tributyl phosphate and an organic diluent to extract uranium from said aqueous stream into said organic phase.

Do network relationships matter? Comparing network and instream habitat variables to explain densities of juvenile coho salmon (Oncorhynchus kisutch) in mid-coastal Oregon, USA

Treesearch

Rebecca L. Flitcroft; Kelly M. Burnett; Gordon H. Reeves; Lisa M. Ganio

2012-01-01

Aquatic ecologists are working to develop theory and techniques for analysis of dynamic stream processes and communities of organisms. Such work is critical for the development of conservation plans that are relevant at the scale of entire ecosystems. The stream network is the foundation upon which stream systems are organized. Natural and human disturbances in streams...

Separation of uranium from technetium in recovery of spent nuclear fuel

DOEpatents

Pruett, David J.; McTaggart, Donald R.

1984-01-01

Uranium and technetium in the product stream of the Purex process for recovery of uranium in spent nuclear fuel are separated by (1) contacting the aqueous Purex product stream with hydrazine to reduce Tc.sup.+7 therein to a reduced species, and (2) contacting said aqueous stream with an organic phase containing tributyl phosphate and an organic diluent to extract uranium from said aqueous stream into said organic phase.

Method for production of magnesium

DOEpatents

Diaz, Alexander F.; Howard, Jack B.; Modestino, Anthony J.; Peters, William A.

1998-01-01

A continuous process for the production of elemental magnesium is described. Magnesium is made from magnesium oxide and a light hydrocarbon gas. In the process, a feed stream of the magnesium oxide and gas is continuously fed into a reaction zone. There the magnesium oxide and gas are reacted at a temperature of about 1400.degree. C. or greater in the reaction zone to provide a continuous product stream of reaction products, which include elemental magnesium. The product stream is continuously quenched after leaving the reaction zone, and the elemental magnesium is separated from other reaction products.

Method for production of magnesium

DOEpatents

Diaz, A.F.; Howard, J.B.; Modestino, A.J.; Peters, W.A.

1998-07-21

A continuous process for the production of elemental magnesium is described. Magnesium is made from magnesium oxide and a light hydrocarbon gas. In the process, a feed stream of the magnesium oxide and gas is continuously fed into a reaction zone. There the magnesium oxide and gas are reacted at a temperature of about 1400 C or greater in the reaction zone to provide a continuous product stream of reaction products, which include elemental magnesium. The product stream is continuously quenched after leaving the reaction zone, and the elemental magnesium is separated from other reaction products. 12 figs.

Water recovery by catalytic treatment of urine vapor

NASA Technical Reports Server (NTRS)

Budininkas, P.; Quattrone, P. D.; Leban, M. I.

1980-01-01

The objective of this investigation was to demonstrate the feasibility of water recovery on a man-rated scale by the catalytic processing of untreated urine vapor. For this purpose, two catalytic systems, one capable of processing an air stream containing low urine vapor concentrations and another to process streams with high urine vapor concentrations, were designed, constructed, and tested to establish the quality of the recovered water.

Production of bio-based fiber gums from the waste streams resulting from the commercial processing of corn bran and oat hulls

USDA-ARS?s Scientific Manuscript database

The U.S. food and non-food industries would benefit from the development of a domestically produced crude, semi-pure and pure bio-based fiber gum from corn bran and oat hulls processing waste streams. When corn bran and oat hulls are processed to produce a commercial cellulose enriched fiber gel, th...

The Cortical Organization of Speech Processing: Feedback Control and Predictive Coding the Context of a Dual-Stream Model

ERIC Educational Resources Information Center

Hickok, Gregory

2012-01-01

Speech recognition is an active process that involves some form of predictive coding. This statement is relatively uncontroversial. What is less clear is the source of the prediction. The dual-stream model of speech processing suggests that there are two possible sources of predictive coding in speech perception: the motor speech system and the…

Modelling the fate of six common pharmaceuticals in a small stream: quantification of attenuation and retention in different stream-specific environments

NASA Astrophysics Data System (ADS)

Riml, Joakim; Wörman, Anders; Kunkel, Uwe; Radke, Michael

2013-04-01

Detection of pharmaceutical residues in streaming waters is common in urbanized areas. Although the occurrence and source of these micropollutants is known, their behavior in these aquatic ecosystems is still only partly understood. Specifically, quantitative information of biogeochemical processes in stream-specific environments where predominant reactions occur is often missing. In an attempt to address this knowledge gap, we performed simultaneous tracer tests in Säva Brook, Sweden, with bezafibrate, clofibric acid, diclofenac, ibuprofen, metoprolol and naproxen, as well as with the more inert solutes uranine and Rhodamine WT. The breakthrough curves at five successive sampling stations along a 16 km long stream reach were evaluated using a coupled physical-biogeochemical model framework containing surface water transport together with a representation of transient storage in slow/immobile zones of the stream. The multi-tracer experiment opens for decoupling of hydrological and biogeochemical contribution to the fate, and by linking impact and sensitivity analyses to relative significance of model parameters the most important processes for each contaminant were elucidated. Specifically for Säva Brook, the proposed methodology revealed that the pharmaceutical-contaminated stream water remained in the storage zones for times corresponding to 5-25% of the flow time of the stream. Furthermore, the results indicate a great variability in terms of predominant biogeochemical processes between the different contaminants. Rapid reactions occurring in the transient storage zone attenuated both ibuprofen and clofibric acid, and we conclude that a major degradation pathway for these contaminants was biodegradation in the hyporheic zone. In contrast, bezafibrate, metoprolol, and naproxen were mainly affected by sorption both in the storage zone and the main channel, while diclofenac displayed negligible effects of biogeochemical reactions.

Sources and Fate of DIC in Swedish Streams

NASA Astrophysics Data System (ADS)

Campeau, A.; Wallin, M.; Bishop, K. H.; Giesler, R.; Mörth, C. M.; Venkiteswaran, J. J.

2015-12-01

DIC export by streams and rivers is a major component of the global C cycle. However, many questions remain about the source and fate of aquatic DIC and CO2. Stable carbon isotope δ13C can provide information about the source and evolution of DIC and CO2 along hydrological networks. But the interpretation of δ13C values must be made with caution, since several biogeochemical processes affect the isotopic signal. In this study, we developed a systematic approach resolving these influences when interpreting large-scale patterns in δ13C-DIC and δ13C-CO2 values with regard to the source and fate of C in low order streams. We analyzed δ13C-DIC values in streams from four different regions of Sweden. Taken together they span large gradients in climate, geomorphology and lithology. The source of the DIC pool was predominantly biogenic in three of the regions (δ13C-DICsource = -17.4‰), but not the northernmost, where a clear geogenic input could be identified (δ13C-DICsource =-8.2 ‰). Our results suggest that soil respired CO2 is the main source of stream CO2 (δ13C-CO2source=-22.9‰) in all four regions, yet aquatic processes can also be a contributing component of the DIC pool in streams, with corresponding influence on the δ13C values. Once CO2 was in the stream, degassing was the primary control on its fate. However, there were indications that aquatic biological processes added CO2, (by DOC degradation) in the southernmost region, and that CO2 was removed (by photosynthesis) in the most central region. Correctly interpreted, the carbon stable isotope data can serve as a powerful tool for identifying the source and fate of stream DIC.

Shuttle radar DEM hydrological correction for erosion modelling in small catchments

NASA Astrophysics Data System (ADS)

Jarihani, Ben; Sidle, Roy; Bartley, Rebecca

2016-04-01

Digital Elevation Models (DEMs) that accurately replicate both landscape form and processes are critical to support modelling of environmental processes. Catchment and hillslope scale runoff and sediment processes (i.e., patterns of overland flow, infiltration, subsurface stormflow and erosion) are all topographically mediated. In remote and data-scarce regions, high resolution DEMs (LiDAR) are often not available, and moderate to course resolution digital elevation models (e.g., SRTM) have difficulty replicating detailed hydrological patterns, especially in relatively flat landscapes. Several surface reconditioning algorithms (e.g., Smoothing) and "Stream burning" techniques (e.g., Agree or ANUDEM), in conjunction with representation of the known stream networks, have been used to improve DEM performance in replicating known hydrology. Detailed stream network data are not available at regional and national scales, but can be derived at local scales from remotely-sensed data. This research explores the implication of high resolution stream network data derived from Google Earth images for DEM hydrological correction, instead of using course resolution stream networks derived from topographic maps. The accuracy of implemented method in producing hydrological-efficient DEMs were assessed by comparing the hydrological parameters derived from modified DEMs and limited high-resolution airborne LiDAR DEMs. The degree of modification is dominated by the method used and availability of the stream network data. Although stream burning techniques improve DEMs hydrologically, these techniques alter DEM characteristics that may affect catchment boundaries, stream position and length, as well as secondary terrain derivatives (e.g., slope, aspect). Modification of a DEM to better reflect known hydrology can be useful, however, knowledge of the magnitude and spatial pattern of the changes are required before using a DEM for subsequent analyses.

Exploring landscapes and ecosystems by studying their streams

NASA Astrophysics Data System (ADS)

Kirchner, J. W.

2016-12-01

Streams integrate fluxes of water, solutes, and sediment from their catchments, and thus they act as mirrors of the surrounding landscape. Patterns of streamflow, chemistry, and sediment flux can therefore shed light on physical, chemical, and biological processes at the scale of whole ecosystems. However, landscapes also exhibit preferential flow and pervasive heterogeneity on all scales, and therefore store waters over a wide spectrum of time scales, complicating efforts to interpret hydrological and geochemical signals in streamwaters. Here I review current and recent research exploring how landscapes store, mix, and release water and solutes to streams. Groundwater levels and stream flows exhibit diurnal cycles in response to snowmelt in springtime and transpiration during the growing season. These cycles vividly illustrate how aquifers and streams mirror ecological processes in their surrounding landscapes. Stream networks extend and retract, both seasonally and in response to individual rainfall events, dynamically mapping out variations in subsurface transmissivity and in the balance between precipitation and transpiration. Water quality time series spanning the periodic table, from H+ to U, exhibit universal fractal scaling on time scales from hours to decades. This scaling behavior is a temporal expression of the spatial heterogeneity that pervades the subsurface, and it confounds efforts to identify water quality trends. Isotope tracers such as 18O, 2H, 3H, and 14C can used to quantify water ages over seven orders of magnitude, from hours to thousands of years. These tracers show that substantial fractions of streamflow are hours, days, and months old, even in streams fed by aquifers with significant proportions of pre-Holocene groundwater. Examples such as these will be presented to illustrate the close coupling between landscapes and the waters that drain them, and to demonstrate how streams can be used as windows into landscape processes.

Stream microbial diversity in response to environmental changes: review and synthesis of existing research

PubMed Central

Zeglin, Lydia H.

2015-01-01

The importance of microbial activity to ecosystem function in aquatic ecosystems is well established, but microbial diversity has been less frequently addressed. This review and synthesis of 100s of published studies on stream microbial diversity shows that factors known to drive ecosystem processes, such as nutrient availability, hydrology, metal contamination, contrasting land-use and temperature, also cause heterogeneity in bacterial diversity. Temporal heterogeneity in stream bacterial diversity was frequently observed, reflecting the dynamic nature of both stream ecosystems and microbial community composition. However, within-stream spatial differences in stream bacterial diversity were more commonly observed, driven specifically by different organic matter (OM) compartments. Bacterial phyla showed similar patterns in relative abundance with regard to compartment type across different streams. For example, surface water contained the highest relative abundance of Actinobacteria, while epilithon contained the highest relative abundance of Cyanobacteria and Bacteroidetes. This suggests that contrasting physical and/or nutritional habitats characterized by different stream OM compartment types may select for certain bacterial lineages. When comparing the prevalence of physicochemical effects on stream bacterial diversity, effects of changing metal concentrations were most, while effects of differences in nutrient concentrations were least frequently observed. This may indicate that although changing nutrient concentrations do tend to affect microbial diversity, other environmental factors are more likely to alter stream microbial diversity and function. The common observation of connections between ecosystem process drivers and microbial diversity suggests that microbial taxonomic turnover could mediate ecosystem-scale responses to changing environmental conditions, including both microbial habitat distribution and physicochemical factors. PMID:26042102

A synoptic survey of microbial respiration, organic matter decomposition, and carbon efflux in U.S. streams and rivers

EPA Science Inventory

We analyzed microbial respiration and ecoenzyme activities related to organic matter processing in 1879 streams and rivers across the continental US as part of the USEPA’s 2008-2009 National Rivers and Streams Assessment. Ecoenzymatic stoichiometry was used to construct models fo...

Auditory Stream Segregation in Autism Spectrum Disorder: Benefits and Downsides of Superior Perceptual Processes

ERIC Educational Resources Information Center

Bouvet, Lucie; Mottron, Laurent; Valdois, Sylviane; Donnadieu, Sophie

2016-01-01

Auditory stream segregation allows us to organize our sound environment, by focusing on specific information and ignoring what is unimportant. One previous study reported difficulty in stream segregation ability in children with Asperger syndrome. In order to investigate this question further, we used an interleaved melody recognition task with…

Stream succession: Channel changes after wildfire disturbance

Treesearch

Nicholas E. Scheidt

2006-01-01

One concept in geomorphology is that vegetation is a fundamental control on sediment and water supplies to streams and, therefore, on downstream fluvial processes and channel morphology. Within this paradigm, wildfire has been implicated as a major driving force behind landscape erosion and changes to stream channels, periodically yielding pulses of sediment from...

Attending to Multiple Visual Streams: Interactions between Location-Based and Category-Based Attentional Selection

ERIC Educational Resources Information Center

Fagioli, Sabrina; Macaluso, Emiliano

2009-01-01

Behavioral studies indicate that subjects are able to divide attention between multiple streams of information at different locations. However, it is still unclear to what extent the observed costs reflect processes specifically associated with spatial attention, versus more general interference due the concurrent monitoring of multiple streams of…

Water quality modeling based on landscape analysis: Importance of riparian hydrology

Treesearch

Thomas Grabs

2010-01-01

Several studies in high-latitude catchments have demonstrated the importance of near-stream riparian zones as hydrogeochemical hotspots with a substantial influence on stream chemistry. An adequate representation of the spatial variability of riparian-zone processes and characteristics is the key for modeling spatiotemporal variations of stream-water quality. This...

Objects, Numbers, Fingers, Space: Clustering of Ventral and Dorsal Functions in Young Children and Adults

ERIC Educational Resources Information Center

Chinello, Alessandro; Cattani, Veronica; Bonfiglioli, Claudia; Dehaene, Stanislas; Piazza, Manuela

2013-01-01

In the primate brain, sensory information is processed along two partially segregated cortical streams: the ventral stream, mainly coding for objects' shape and identity, and the dorsal stream, mainly coding for objects' quantitative information (including size, number, and spatial position). Neurophysiological measures indicate that such…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bartholomew, M. J.

To improve the quantitative description of precipitation processes in climate models, the Atmospheric Radiation Measurement (ARM) Climate Research Facility deployed rain gauges located near disdrometers (DISD and VDIS data streams). This handbook deals specifically with the rain gauges that make the observations for the RAIN data stream. Other precipitation observations are made by the surface meteorology instrument suite (i.e., MET data stream).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elicio, Andy U.

My ERM 593 applied project will provide guidance for the Los Alamos National Laboratory Waste Stream Profile reviewer (i.e. RCRA reviewer) in regards to Reviewing and Approving a Waste Stream Profile in the Waste Compliance and Tracking System. The Waste Compliance and Tracking system is called WCATS. WCATS is a web-based application that “supports the generation, characterization, processing and shipment of LANL radioactive, hazardous, and industrial waste.” The LANL generator must characterize their waste via electronically by filling out a waste stream profile (WSP) in WCATS. Once this process is completed, the designated waste management coordinator (WMC) will perform amore » review of the waste stream profile to ensure the generator has completed their waste stream characterization in accordance with applicable state, federal and LANL directives particularly P930-1, “LANL Waste Acceptance Criteria,” and the “Waste Compliance and Tracking System User's Manual, MAN-5004, R2,” as applicable. My guidance/applied project will describe the purpose, scope, acronyms, definitions, responsibilities, assumptions and guidance for the WSP reviewer as it pertains to each panel and subpanel of a waste stream profile.« less

SDF1 regulates leading process branching and speed of migrating interneurons

PubMed Central

Lysko, Daniel E.; Putt, Mary; Golden, Jeffrey A.

2011-01-01

Cell migration is required for normal embryonic development, yet how cells navigate complex paths while integrating multiple guidance cues remains poorly understood. During brain development, interneurons migrate from the ventral ganglionic eminence to the cerebral cortex within several migratory streams. They must exit these streams to invade the cortical plate. While SDF1-signaling is necessary for normal interneuron stream migration, how they switch from tangential stream migration to invade the cortical plate is unknown. Here we demonstrate that SDF1-signaling reduces interneuron branching frequency by reducing cAMP levels via a Gi-signaling pathway using an in vitro mouse explant system, resulting in the maintenance of stream migration. Blocking SDF1-signaling, or increasing branching frequency, results in stream exit and cortical plate invasion in mouse brain slices. These data support a novel model to understand how migrating interneurons switch from tangential migration to invade the cortical plate in which reducing SDF1-signaling increases leading process branching and slows the migration rate, permitting migrating interneurons to sense cortically directed guidance cues. PMID:21289183

Discharge process of cesium during rainstorms in headwater catchments, Fukushima, Japan

NASA Astrophysics Data System (ADS)

Tsujimura, Maki; Onda, Yuichi; Iwagami, Sho; Nishino, Masataka; Konuma, Ryohei

2014-05-01

We monitored Cs-137 concentrations in stream water, groundwater, soil water and rainwater in the Yamakiya district located approximately 35 km north west of Fukushima Dai-ichi Nuclear Power Plant (FDNPP) from June 2011 through July 2013, focusing on rainfall-runoff processes during the rainstorm events. Two catchments with different land cover (Iboishiyama and Koutaishiyama) were instrumentd, and stream water, groundwater, soil water and rainwater were sampled for approximately one month at each site, and intensive sampling was conducted during rainstorm events. The 137Cs concentration in stream water showed a relatively quick decreasing trend during 2011. Also, during rainfall events, the Cs-137 concentration in stream water showed a temporary increase. End Member Mixing Analysis was applied to evaluate contribution of groundwater, soil water and rainwater in discharge water during rainstorm events. The groundwater component was dominant in the runoff, whereas rainwater was main source for the Cs-137 concentration of the stream increasing during the storm events. In addition, a leaching of Cs-137 from the suspended sediments and the organic materials seemed to be also important sources to the stream.

Actin Polymerization Is Essential for Pollen Tube GrowthV⃞

PubMed Central

Vidali, Luis; McKenna, Sylvester T.; Hepler, Peter K.

2001-01-01

Actin microfilaments, which are prominent in pollen tubes, have been implicated in the growth process; however, their mechanism of action is not well understood. In the present work we have used profilin and DNAse I injections, as well as latrunculin B and cytochalasin D treatments, under quantitatively controlled conditions, to perturb actin microfilament structure and assembly in an attempt to answer this question. We found that a ∼50% increase in the total profilin pool was necessary to half-maximally inhibit pollen tube growth, whereas a ∼100% increase was necessary for half-maximal inhibition of cytoplasmic streaming. DNAse I showed a similar inhibitory activity but with a threefold more pronounced effect on growth than streaming. Latrunculin B, at only 1–4 nM in the growth medium, has a similar proportion of inhibition of growth over streaming to that of profilin. The fact that tip growth is more sensitive than streaming to the inhibitory substances and that there is no correlation between streaming and growth rates suggests that tip growth requires actin assembly in a process independent of cytoplasmic streaming. PMID:11514633

Dynamic modeling of nitrogen losses in river networks unravels the coupled effects of hydrological and biogeochemical processes

USGS Publications Warehouse

Alexander, Richard B.; Böhlke, John Karl; Boyer, Elizabeth W.; David, Mark B.; Harvey, Judson W.; Mulholland, Patrick J.; Seitzinger, Sybil P.; Tobias, Craig R.; Tonitto, Christina; Wollheim, Wilfred M.

2009-01-01

The importance of lotic systems as sinks for nitrogen inputs is well recognized. A fraction of nitrogen in streamflow is removed to the atmosphere via denitrification with the remainder exported in streamflow as nitrogen loads. At the watershed scale, there is a keen interest in understanding the factors that control the fate of nitrogen throughout the stream channel network, with particular attention to the processes that deliver large nitrogen loads to sensitive coastal ecosystems. We use a dynamic stream transport model to assess biogeochemical (nitrate loadings, concentration, temperature) and hydrological (discharge, depth, velocity) effects on reach-scale denitrification and nitrate removal in the river networks of two watersheds having widely differing levels of nitrate enrichment but nearly identical discharges. Stream denitrification is estimated by regression as a nonlinear function of nitrate concentration, streamflow, and temperature, using more than 300 published measurements from a variety of US streams. These relations are used in the stream transport model to characterize nitrate dynamics related to denitrification at a monthly time scale in the stream reaches of the two watersheds. Results indicate that the nitrate removal efficiency of streams, as measured by the percentage of the stream nitrate flux removed via denitrification per unit length of channel, is appreciably reduced during months with high discharge and nitrate flux and increases during months of low-discharge and flux. Biogeochemical factors, including land use, nitrate inputs, and stream concentrations, are a major control on reach-scale denitrification, evidenced by the disproportionately lower nitrate removal efficiency in streams of the highly nitrate-enriched watershed as compared with that in similarly sized streams in the less nitrate-enriched watershed. Sensitivity analyses reveal that these important biogeochemical factors and physical hydrological factors contribute nearly equally to seasonal and stream-size related variations in the percentage of the stream nitrate flux removed in each watershed.

Assessment of attenuation processes in a chlorinated ethene plume by use of stream bed Passive Flux Meters, streambed Point Velocity Probes and contaminant mass balances

NASA Astrophysics Data System (ADS)

Rønde, V.; McKnight, U. S.; Annable, M. D.; Devlin, J. F.; Cremeans, M.; Sonne, A. T.; Bjerg, P. L.

2017-12-01

Chlorinated ethenes (CE) are abundant groundwater contaminants and pose risk to both groundwater and surface water bodies, as plumes can migrate through aquifers to streams. After release to the environment, CE may undergo attenuation. The hyporheic zone is believed to enhance CE attenuation, however studies contradicting this have also been reported. Since dilution commonly reduces contaminant concentrations in streams to below quantification limits, use of mass balances along the pathway from groundwater to stream is unusual. Our study is conducted at the low-land Grindsted stream, Denmark, which is impacted by a contaminant plume. CE have been observed in the stream water; hence our study site provides an unusual opportunity to study attenuation processes in a CE plume as it migrates through the groundwater at the stream bank, through the stream bed and further to the point of fully mixed conditions in the stream. The study undertook the determination of redox conditions and CE distribution from bank to stream; streambed contaminant flux estimation using streambed Passive Flux Meters (sPFM); and quantification of streambed water fluxes using temperature profiling and streambed Point Velocity Probes (SBPVP). The advantage of the sPFM is that it directly measures the contaminant flux without the need for water samples, while the advantage of the SBPVP is its ability to measure the vertical seepage velocity without the need for additional geological parameters. Finally, a mass balance assessment along the plume pathway was conducted to account for any losses or accumulations. The results show consistencies in spatial patterns between redox conditions and extent of dechlorination; between contaminant fluxes from sPFM and concentrations from water samples; and between seepage velocities from SBPVP and temperature-based water fluxes. Mass balances and parent-metabolite compound ratios indicate limited degradation between the bank and the point of fully mixed stream water. Since the plume at the bank mainly consists of cis-DCE and vinyl chloride, this implies high and persistent stream water concentrations of these compounds. Finally, this study demonstrates the usefulness and complementary nature of sPFM and SBPVP measurements for assessing the attenuation processes through mass balance calculations.

40 CFR 63.496 - Back-end process provisions-procedures to determine compliance with residual organic HAP...

Code of Federal Regulations, 2012 CFR

2012-07-01

... methods of determining this quantity are production records, measurement of stream characteristics, and... HAP (or TOC, minus methane and ethane) emissions in all process vent streams and primary and secondary... heater. (B) Paragraph (b)(5)(iii) of this section is applicable, except that TOC (minus methane and...

40 CFR 63.496 - Back-end process provisions-procedures to determine compliance with residual organic HAP...

Code of Federal Regulations, 2014 CFR

2014-07-01

... methods of determining this quantity are production records, measurement of stream characteristics, and... HAP (or TOC, minus methane and ethane) emissions in all process vent streams and primary and secondary... heater. (B) Paragraph (b)(5)(iii) of this section is applicable, except that TOC (minus methane and...

40 CFR 63.496 - Back-end process provisions-procedures to determine compliance with residual organic HAP...

Code of Federal Regulations, 2011 CFR

2011-07-01

... methods of determining this quantity are production records, measurement of stream characteristics, and... HAP (or TOC, minus methane and ethane) emissions in all process vent streams and primary and secondary... heater. (B) Paragraph (b)(5)(iii) of this section is applicable, except that TOC (minus methane and...

40 CFR 63.496 - Back-end process provisions-procedures to determine compliance with residual organic HAP...

Code of Federal Regulations, 2013 CFR

2013-07-01

... methods of determining this quantity are production records, measurement of stream characteristics, and... HAP (or TOC, minus methane and ethane) emissions in all process vent streams and primary and secondary... heater. (B) Paragraph (b)(5)(iii) of this section is applicable, except that TOC (minus methane and...

Effects of invertebrates in lotic ecosystem processes

Treesearch

J.B. Wallace; J.J. Jr. Hutchens

2000-01-01

Freshwater invertebrates perform many roles in ecosystem processes (Palmer et al., 1997) and these roles are frequently associated with a diverse array of feeding habits which have been organized into functional feeding groups (FFGs). Wallace and Webster (1996) reviewed many roles ofFFGs in stream ecosystems. Streams differ markedly from most ecosystems in that the...

Dissolved carbon and nitrogen losses from forests of the Oregon Cascades over a successional gradient

EPA Science Inventory

Ecologists have long used stream water chemistry records to infer hillslope processes, although a great deal of biogeochemical processing of soil water is known to occur both downslope and in-stream. We report the effects of forest succession on C and N export in the west central...

WOOD PRODUCTS IN THE WASTE STREAM: CHARACTERIZATION AND COMBUSTION EMISSIONS - VOLUME 2. APPENDICES

EPA Science Inventory

The report gives results of a study of technical, public policy, and regulatory issues that affect the processing and combustion of waste wood for fuel. (NOTE: Waste wood is wood that is separated from a solid-waste stream, processed into a uniform-sized product, and reused for o...

WOOD PRODUCTS IN THE WASTE STREAM: CHARACTERIZATION AND COMBUSTION EMISSIONS - VOLUME 1. TECHNICAL REPORT

EPA Science Inventory

The report gives results of a study of technical, public policy, and regulatory issues that affect the processing and combustion of waste wood for fuel. (NOTE: Waste wood is wood that is separated from a solid-waste stream, processed into a uniform-sized product, and reused for o...

Side Streams of Plant Food Processing As a Source of Valuable Compounds: Selected Examples.

PubMed

Schieber, Andreas

2017-02-28

Industrial processing of plant-derived raw materials generates enormous amounts of by-products. On one hand, these by-products constitute a serious disposal issue because they often emerge seasonally and are prone to microbial decay. On the other hand, they are an abundant source of valuable compounds, in particular secondary plant metabolites and cell wall materials, which may be recovered and used to functionalize foods and replace synthetic additives with ingredients of natural origin. This review covers 150 references and presents select studies performed between 2001 and 2016 on the recovery, characterization, and application of valuable constituents from grape pomace, apple pomace, potato peels, tomato pomace, carrot pomace, onion peels, by-products of citrus, mango, banana, and pineapple processing, side streams of olive oil production, and cereal by-products. The criteria used were economic importance, amounts generated, relevance of side streams as a source of valuable compounds, and reviews already published. Despite a plethora of studies carried out on the utilization of side streams, relatively few processes have yet found industrial application.

Whole-stream response to nitrate loading in three streams draining agricultural landscapes

USGS Publications Warehouse

Duff, J.H.; Tesoriero, A.J.; Richardson, W.B.; Strauss, E.A.; Munn, M.D.

2008-01-01

Physical, chemical, hydrologic, and biologic factors affecting nitrate (NO3 −) removal were evaluated in three agricultural streams draining orchard/dairy and row crop settings. Using 3-d “snapshots” during biotically active periods, we estimated reach-level NO3 − sources, NO3 − mass balance, in-stream processing (nitrification, denitrification, and NO3 − uptake), and NO3 − retention potential associated with surface water transport and ground water discharge. Ground water contributed 5 to 11% to stream discharge along the study reaches and 8 to 42% of gross NO3 − input. Streambed processes potentially reduced 45 to 75% of ground water NO3 − before discharge to surface water. In all streams, transient storage was of little importance for surface water NO3 − retention. Estimated nitrification (1.6–4.4 mg N m−2 h−1) and unamended denitrification rates (2.0–16.3 mg N m−2 h−1) in sediment slurries were high relative to pristine streams. Denitrification of NO3 − was largely independent of nitrification because both stream and ground water were sources of NO3 − Unamended denitrification rates extrapolated to the reach-scale accounted for <5% of NO3 − exported from the reaches minimally reducing downstream loads. Nitrate retention as a percentage of gross NO3 − inputs was >30% in an organic-poor, autotrophic stream with the lowest denitrification potentials and highest benthic chlorophyll a, photosynthesis/respiration ratio, pH, dissolved oxygen, and diurnal NO3 − variation. Biotic processing potentially removed 75% of ground water NO3 − at this site, suggesting an important role for photosynthetic assimilation of ground water NO3 − relative to subsurface denitrification as water passed directly through benthic diatom beds.

Using a Spectral Method to Evaluate Hyporheic Exchange and its Effect on Reach Scale Nitrate Removal.

NASA Astrophysics Data System (ADS)

Moren, I.; Worman, A. L. E.; Riml, J.

2017-12-01

Previous studies have shown that hyporheic exchange processes can be of great importance for the transport, retention and mass removal of nutrients in streams. Specifically, the flow of surface water through the hyporheic zone enhances redox-sensitive reactions such as coupled nitrification-denitrification. This self-cleaning capacity of streams can be utilized in stream restoration projects aiming to improve water quality by reconstructing the geomorphology of the streams. To optimize the effect of restoration actions we need quantitative understanding of the linkage between stream geomorphology, hyporheic exchange processes and the desired water quality targets. Here we propose an analytical, spectral methodology to evaluate how different stream geomorphologies induce hyporheic exchange on a wide range of spatial and temporal scales. Measurements of streambed topographies and surface water profiles from agricultural streams were used to calculate the average hyporheic exchange velocity and residence times and the result was compared with in-stream tracer test. Furthermore, the hyporheic exchange induced by steps in the surface water profile was derived as a comparison of the theoretical capacity of the system. Based on differences in hyporheic exchange, the mass removal of nitrate could be derived for the different geomorphologies. The maximum nitrate mass removal was found to be related to a specific Damkhöler number, which reflects that the mass removal can be either reaction or transport controlled. Therefore, although hyporheic exchange induced by steps in the surface water profile was generally larger than the hyporheic exchange in the observed natural reaches, this would not necessarily lead a larger nitrate mass removal provided that the hyporheic residence times are not long enough to facilitate denitrification processes. The study illustrates the importance to investigate a stream thoroughly before any remediation actions are implemented, specifically to evaluate if the mass removal is reaction or transport controlled.

Quantifying in-stream nitrate reaction rates using continuously-collected water quality data

Treesearch

Matthew Miller; Anthony Tesoriero; Paul Capel

2016-01-01

High frequency in situ nitrate data from three streams of varying hydrologic condition, land use, and watershed size were used to quantify the mass loading of nitrate to streams from two sources – groundwater discharge and event flow – at a daily time step for one year. These estimated loadings were used to quantify temporally-variable in-stream nitrate processing ...

A River Runs Under It: Modeling the Distribution of Streams and Stream Burial in Large River Basins

NASA Astrophysics Data System (ADS)

Elmore, A. J.; Julian, J.; Guinn, S.; Weitzell, R.; Fitzpatrick, M.

2011-12-01

Stream network density exerts a strong control on hydrologic processes in watersheds. Over land and through soil and bedrock substrate, water moves slowly and is subject to chemical transformations unique to conditions of continuous contact with geologic materials. In contrast, once water enters stream channels it is efficiently transported out of watersheds, reducing the amount of time for biological uptake and stream nutrient processing. Therefore, stream network density dictates both the relative importance of terrestrial and aquatic influences to stream chemistry and the residence time of water in watersheds, and is critical to modeling and empirical studies aimed at understanding the impact of land use on stream water quantity and quality. Stream network density is largely a function of the number and length of the smallest streams. Methods for mapping and measuring these headwater streams range from simple measurement of stream length from existing maps, to detailed field mapping efforts, which are difficult to implement over large areas. Confounding the simplest approaches, many headwater stream reaches are not included in hydrographical maps, such as the U.S. National Hydrography Dataset (NHD), either because they were buried during the course of urban development or because they were seen as smaller than the minimum mapping size at the time of map generation. These "missing streams" severely limit the effective analyses of stream network density based on the NHD, constituting a major problem for many efforts to understand land-use impacts on streams. Here we report on research that predicts stream presence and absence by coupling field observations of headwater stream channels with maximum entropy models (MaxEnt) commonly implemented in biogeographical studies to model species distributions. The model utilizes terrain variables that are continuously accumulated along hydrologic flowpaths derived from a 10-m digital elevation model. In validation, the model correctly predicts the presence of 91% of all 10-m stream segments, and rarely miscalculates tributary numbers. We apply this model to the entire Potomac River Basin (37,800 km2) and several adjacent basins to map stream channel density and compare our results with NHD flowline data. We find that NHD underestimates stream channel density by a factor of two in most sub watersheds and this effect is strongest in the densely urbanized cities of Washington, DC and Baltimore, MD. We then apply a second predictive model based on impervious surface area data to map the extent of stream burial. Results demonstrate that the extent of stream burial increases with decreasing stream catchment area. When applied at four time steps (1975, 1990, 2001, and 2006), we find that although stream burial rates have slowed in the recent decade, streams that are not mapped in NHD flowline data continue to be buried during development. This work is the most ambitious attempt yet to map stream network density over a large region and will have lasting implications for modeling and conservation efforts.

Vision for perception and vision for action in the primate brain.

PubMed

Goodale, M A

1998-01-01

Visual systems first evolved not to enable animals to see, but to provide distal sensory control of their movements. Vision as 'sight' is a relative newcomer to the evolutionary landscape, but its emergence has enabled animals to carry out complex cognitive operations on perceptual representations of the world. The two streams of visual processing that have been identified in the primate cerebral cortex are a reflection of these two functions of vision. The dorsal 'action' stream projecting from primary visual cortex to the posterior parietal cortex provides flexible control of more ancient subcortical visuomotor modules for the production of motor acts. The ventral 'perceptual' stream projecting from the primary visual cortex to the temporal lobe provides the rich and detailed representation of the world required for cognitive operations. Both streams process information about the structure of objects and about their spatial locations--and both are subject to the modulatory influences of attention. Each stream, however, uses visual information in different ways. Transformations carried out in the ventral stream permit the formation of perceptual representations that embody the enduring characteristics of objects and their relations; those carried out in the dorsal stream which utilize moment-to-moment information about objects within egocentric frames of reference, mediate the control of skilled actions. Both streams work together in the production of goal-directed behaviour.

Long-term enrichment of the stable isotopic composition of stream water due to the release of groundwater recharge from extreme precipitation events

NASA Astrophysics Data System (ADS)

Boutt, D. F.

2017-12-01

The isotopic composition of surface and groundwater is impacted by a multitude of hydrologic processes. The long-term response of these systems to hydrologic change is critical for appropriately interpreting isotopic information for streamflow generation, stream-aquifer-coupling, sources of water to wells, and understanding recharge processes. To evaluate the response time of stream-aquifer systems to extreme precipitation events we use a long-term isotope dataset from Western Massachusetts with drainage areas ranging from 0.1 to > 800 km2. The year of 2011 was the wettest calendar year on record and the months of August and September of 2011 were the wettest consecutive two-month period in the 123 year record. Stable isotopic composition of surface waters of catchments ranging from 1 - 1000 km2 show an enrichment due to summertime and Tropical Storm precipitation. Enrichment in potential recharge water is shown to have a significant long-term impact (> 3 hydrologic years) on the isotopic composition of both surface and groundwater. This highlights the importance of groundwater sources of baseflow to streams and the transient storage and release mechanisms of shallow groundwater storage. The length of isotopic recession of stream water are also a strong function of watershed area. It is concluded that the stream water isotopes are consistent with a large pulse of water being stored and released from enriched groundwater emplaced during this period of above-average precipitation. Ultimately the results point to the importance of considering hydrological processes of streamflow generation and their role in hydrologic processes beyond traditional catchment response analysis.

Network analysis reveals multiscale controls on streamwater chemistry

USGS Publications Warehouse

McGuire, Kevin J.; Torgersen, Christian E.; Likens, Gene E.; Buso, Donald C.; Lowe, Winsor H.; Bailey, Scott W.

2014-01-01

By coupling synoptic data from a basin-wide assessment of streamwater chemistry with network-based geostatistical analysis, we show that spatial processes differentially affect biogeochemical condition and pattern across a headwater stream network. We analyzed a high-resolution dataset consisting of 664 water samples collected every 100 m throughout 32 tributaries in an entire fifth-order stream network. These samples were analyzed for an exhaustive suite of chemical constituents. The fine grain and broad extent of this study design allowed us to quantify spatial patterns over a range of scales by using empirical semivariograms that explicitly incorporated network topology. Here, we show that spatial structure, as determined by the characteristic shape of the semivariograms, differed both among chemical constituents and by spatial relationship (flow-connected, flow-unconnected, or Euclidean). Spatial structure was apparent at either a single scale or at multiple nested scales, suggesting separate processes operating simultaneously within the stream network and surrounding terrestrial landscape. Expected patterns of spatial dependence for flow-connected relationships (e.g., increasing homogeneity with downstream distance) occurred for some chemical constituents (e.g., dissolved organic carbon, sulfate, and aluminum) but not for others (e.g., nitrate, sodium). By comparing semivariograms for the different chemical constituents and spatial relationships, we were able to separate effects on streamwater chemistry of (i) fine-scale versus broad-scale processes and (ii) in-stream processes versus landscape controls. These findings provide insight on the hierarchical scaling of local, longitudinal, and landscape processes that drive biogeochemical patterns in stream networks.

Network analysis reveals multiscale controls on streamwater chemistry

PubMed Central

McGuire, Kevin J.; Torgersen, Christian E.; Likens, Gene E.; Buso, Donald C.; Lowe, Winsor H.; Bailey, Scott W.

2014-01-01

By coupling synoptic data from a basin-wide assessment of streamwater chemistry with network-based geostatistical analysis, we show that spatial processes differentially affect biogeochemical condition and pattern across a headwater stream network. We analyzed a high-resolution dataset consisting of 664 water samples collected every 100 m throughout 32 tributaries in an entire fifth-order stream network. These samples were analyzed for an exhaustive suite of chemical constituents. The fine grain and broad extent of this study design allowed us to quantify spatial patterns over a range of scales by using empirical semivariograms that explicitly incorporated network topology. Here, we show that spatial structure, as determined by the characteristic shape of the semivariograms, differed both among chemical constituents and by spatial relationship (flow-connected, flow-unconnected, or Euclidean). Spatial structure was apparent at either a single scale or at multiple nested scales, suggesting separate processes operating simultaneously within the stream network and surrounding terrestrial landscape. Expected patterns of spatial dependence for flow-connected relationships (e.g., increasing homogeneity with downstream distance) occurred for some chemical constituents (e.g., dissolved organic carbon, sulfate, and aluminum) but not for others (e.g., nitrate, sodium). By comparing semivariograms for the different chemical constituents and spatial relationships, we were able to separate effects on streamwater chemistry of (i) fine-scale versus broad-scale processes and (ii) in-stream processes versus landscape controls. These findings provide insight on the hierarchical scaling of local, longitudinal, and landscape processes that drive biogeochemical patterns in stream networks. PMID:24753575

Network analysis reveals multiscale controls on streamwater chemistry.

PubMed

McGuire, Kevin J; Torgersen, Christian E; Likens, Gene E; Buso, Donald C; Lowe, Winsor H; Bailey, Scott W

2014-05-13

By coupling synoptic data from a basin-wide assessment of streamwater chemistry with network-based geostatistical analysis, we show that spatial processes differentially affect biogeochemical condition and pattern across a headwater stream network. We analyzed a high-resolution dataset consisting of 664 water samples collected every 100 m throughout 32 tributaries in an entire fifth-order stream network. These samples were analyzed for an exhaustive suite of chemical constituents. The fine grain and broad extent of this study design allowed us to quantify spatial patterns over a range of scales by using empirical semivariograms that explicitly incorporated network topology. Here, we show that spatial structure, as determined by the characteristic shape of the semivariograms, differed both among chemical constituents and by spatial relationship (flow-connected, flow-unconnected, or Euclidean). Spatial structure was apparent at either a single scale or at multiple nested scales, suggesting separate processes operating simultaneously within the stream network and surrounding terrestrial landscape. Expected patterns of spatial dependence for flow-connected relationships (e.g., increasing homogeneity with downstream distance) occurred for some chemical constituents (e.g., dissolved organic carbon, sulfate, and aluminum) but not for others (e.g., nitrate, sodium). By comparing semivariograms for the different chemical constituents and spatial relationships, we were able to separate effects on streamwater chemistry of (i) fine-scale versus broad-scale processes and (ii) in-stream processes versus landscape controls. These findings provide insight on the hierarchical scaling of local, longitudinal, and landscape processes that drive biogeochemical patterns in stream networks.

Random Number Generation for High Performance Computing

DTIC Science & Technology

2015-01-01

number streams, a quality metric for the parallel random number streams. * * * * * Atty. Dkt . No.: 5660-14400 Customer No. 35690 Eric B. Meyertons...responsibility to ensure timely payment of maintenance fees when due. Pagel of3 PTOL-85 (Rev. 02/11) Atty. Dkt . No.: 5660-14400 Page 1 Meyertons...with each subtask executed by a separate thread or process (henceforth, process). Each process has Atty. Dkt . No.: 5660-14400 Page 2 Meyertons

Microbial removal of no.sub.x from gases

DOEpatents

Sublette, Kerry L.

1991-01-01

Disclosed is a process by which a gas containing nitric oxide is contacted with an anaerobic microbial culture of denitrifying bacteria to effect the chemical reduction of the nitric oxide to elemental nitrogen. The process is particularly suited to the removal of nitric oxide from flue gas streams and gas streams from nitric acid plants. Thiobacillus dentrificians as well as other bacteria are disclosed for use in the process.

Flexible biorefinery for producing fermentation sugars, lignin and pulp from corn stover.

PubMed

Kadam, Kiran L; Chin, Chim Y; Brown, Lawrence W

2008-05-01

A new biorefining process is presented that embodies green processing and sustainable development. In the spirit of a true biorefinery, the objective is to convert agricultural residues and other biomass feedstocks into value-added products such as fuel ethanol, dissolving pulp, and lignin for resin production. The continuous biomass fractionation process yields a liquid stream rich in hemicellulosic sugars, a lignin-rich liquid stream, and a solid cellulose stream. This paper generally discusses potential applications of the three streams and specifically provides results on the evaluation of the cellulose stream from corn stover as a source of fermentation sugars and specialty pulp. Enzymatic hydrolysis of this relatively pure cellulose stream requires significantly lower enzyme loadings because of minimal enzyme deactivation from nonspecific binding to lignin. A correlation was shown to exist between lignin removal efficiency and enzymatic digestibility. The cellulose produced was also demonstrated to be a suitable replacement for hardwood pulp, especially in the top ply of a linerboard. Also, the relatively pure nature of the cellulose renders it suitable as raw material for making dissolving pulp. This pulping approach has significantly smaller environmental footprint compared to the industry-standard kraft process because no sulfur- or chlorine-containing compounds are used. Although this option needs some minimal post-processing, it produces a higher value commodity than ethanol and, unlike ethanol, does not need extensive processing such as hydrolysis or fermentation. Potential use of low-molecular weight lignin as a raw material for wood adhesive production is discussed as well as its use as cement and feed binder. As a baseline application the hemicellulosic sugars captured in the hydrolyzate liquor can be used to produce ethanol, but potential utilization of xylose for xylitol fermentation is also feasible. Markets and values of these applications are juxtaposed with market penetration and saturation.

Thermodynamic and economic analysis of heat pumps for energy recovery in industrial processes

NASA Astrophysics Data System (ADS)

Urdaneta-B, A. H.; Schmidt, P. S.

1980-09-01

A computer code has been developed for analyzing the thermodynamic performance, cost and economic return for heat pump applications in industrial heat recovery. Starting with basic defining characteristics of the waste heat stream and the desired heat sink, the algorithm first evaluates the potential for conventional heat recovery with heat exchangers, and if applicable, sizes the exchanger. A heat pump system is then designed to process the residual heating and cooling requirements of the streams. In configuring the heat pump, the program searches a number of parameters, including condenser temperature, evaporator temperature, and condenser and evaporator approaches. All system components are sized for each set of parameters, and economic return is estimated and compared with system economics for conventional processing of the heated and cooled streams (i.e., with process heaters and coolers). Two case studies are evaluated, one in a food processing application and the other in an oil refinery unit.

Integrated coke, asphalt and jet fuel production process and apparatus

DOEpatents

Shang, Jer Y.

1991-01-01

A process and apparatus for the production of coke, asphalt and jet fuel m a feed of fossil fuels containing volatile carbon compounds therein is disclosed. The process includes the steps of pyrolyzing the feed in an entrained bed pyrolyzing means, separating the volatile pyrolysis products from the solid pyrolysis products removing at least one coke from the solid pyrolysis products, fractionating the volatile pyrolysis products to produce an overhead stream and a bottom stream which is useful as asphalt for road pavement, condensing the overhead stream to produce a condensed liquid fraction and a noncondensable, gaseous fraction, and removing water from the condensed liquid fraction to produce a jet fuel-containing product. The disclosed apparatus is useful for practicing the foregoing process. the process provides a useful method of mass producing and jet fuels from materials such as coal, oil shale and tar sands.

Integrated Water Flow Model (IWFM), A Tool For Numerically Simulating Linked Groundwater, Surface Water And Land-Surface Hydrologic Processes

NASA Astrophysics Data System (ADS)

Dogrul, E. C.; Brush, C. F.; Kadir, T. N.

2006-12-01

The Integrated Water Flow Model (IWFM) is a comprehensive input-driven application for simulating groundwater flow, surface water flow and land-surface hydrologic processes, and interactions between these processes, developed by the California Department of Water Resources (DWR). IWFM couples a 3-D finite element groundwater flow process and 1-D land surface, lake, stream flow and vertical unsaturated-zone flow processes which are solved simultaneously at each time step. The groundwater flow system is simulated as a multilayer aquifer system with a mixture of confined and unconfined aquifers separated by semiconfining layers. The groundwater flow process can simulate changing aquifer conditions (confined to unconfined and vice versa), subsidence, tile drains, injection wells and pumping wells. The land surface process calculates elemental water budgets for agricultural, urban, riparian and native vegetation classes. Crop water demands are dynamically calculated using distributed soil properties, land use and crop data, and precipitation and evapotranspiration rates. The crop mix can also be automatically modified as a function of pumping lift using logit functions. Surface water diversions and groundwater pumping can each be specified, or can be automatically adjusted at run time to balance water supply with water demand. The land-surface process also routes runoff to streams and deep percolation to the unsaturated zone. Surface water networks are specified as a series of stream nodes (coincident with groundwater nodes) with specified bed elevation, conductance and stage-flow relationships. Stream nodes are linked to form stream reaches. Stream inflows at the model boundary, surface water diversion locations, and one or more surface water deliveries per location are specified. IWFM routes stream flows through the network, calculating groundwater-surface water interactions, accumulating inflows from runoff, and allocating available stream flows to meet specified or calculated deliveries. IWFM utilizes a very straight-forward input file structure, allowing rapid development of complex simulations. A key feature of IWFM is a new algorithm for computation of groundwater flow across element faces. Enhancements to version 3.0 include automatic time-tracking of input and output data sets, linkage with the HEC-DSS database, and dynamic crop allocation using logit functions. Utilities linking IWFM to the PEST automated calibration suite are also available. All source code, executables and documentation are available for download from the DWR web site. IWFM is currently being used to develop hydrologic simulations of California's Central Valley (C2VSIM); the west side of California's San Joaquin Valley (WESTSIM); Butte County, CA; Solano County, CA; Merced County, CA; and the Oregon side of the Walla Walla River Basin.

Streaming simplification of tetrahedral meshes.

PubMed

Vo, Huy T; Callahan, Steven P; Lindstrom, Peter; Pascucci, Valerio; Silva, Cláudio T

2007-01-01

Unstructured tetrahedral meshes are commonly used in scientific computing to represent scalar, vector, and tensor fields in three dimensions. Visualization of these meshes can be difficult to perform interactively due to their size and complexity. By reducing the size of the data, we can accomplish real-time visualization necessary for scientific analysis. We propose a two-step approach for streaming simplification of large tetrahedral meshes. Our algorithm arranges the data on disk in a streaming, I/O-efficient format that allows coherent access to the tetrahedral cells. A quadric-based simplification is sequentially performed on small portions of the mesh in-core. Our output is a coherent streaming mesh which facilitates future processing. Our technique is fast, produces high quality approximations, and operates out-of-core to process meshes too large for main memory.

Factors affecting ammonium uptake in streams - an inter-biome perspective

Treesearch

Jackson R Webster; Partick J. Mulholland; Jennifer L. Tanks; H. Maurice Valett; Walter K. Dodds; Bruce J. Peterson; William B. Bowden; Clifford N. Dahm; Stuart Findlay; Stanley V. Gregory; Nancy B. Grimm; Stephen K. Hamilton; Sherri L. Johnson; Eugenia Marti; William H. McDowell; Judy L. Meyer; Donna D. Morrall; Steven A. Thomas; Wilfred M. Wollhem

2003-01-01

1. The Lotic Intersite Nitrogen experiment (LINX) was a coordinated study of the relationships between North American biomes and factors governing ammonium uptake in streams. Our objective was to relate inter-biome variability of ammonium uptake to physical, chemical and biological processes. 2. Data were collected from 11 streams ranging from arctic to tropical and...

Effects of agriculture on wood breakdown and microbial biofilm respiration in southern Appalachian streams

Treesearch

M.E. McTammany; E.F. Benfield; J.R. Webster

2008-01-01

Agriculture causes high sediment, nutrient and light input to streams, which may affect rates of ecosystem processes, such as organic matter decay. In the southern Appalachians, socioeconomic trends over the past 50 years have caused widespread abandonment of farmland with subsequent reforestation. Physical and chemical properties of streams in these...

Effects of agriculture on wood breakdown and microbial biofilm respiration in southern Appalachian streams

Treesearch

E.F Benfield McTammany; J.R. Webster

2008-01-01

Agriculture causes high sediment, nutrient and light input to streams, which may affect rates of ecosystem processes, such as organic matter decay. In the southern Appalachians, socioeconomic trends over the past 50 years have caused widespread abandonment of farmland with subsequent reforestation. Physical and chemical properties of streams in these reforested areas...

Hydrological connectivity of hillslopes and streams: characteristic time scales and nonlinearities

Treesearch

Kevin J. McGuire; Jeffrey J. McDonnell

2010-01-01

Subsurface flow from hillslopes is widely recognized as an important contributor to streamflow generation; however, processes that control how and when hillslopes connect to streams remain unclear. We investigated stream and hillslope runoff dynamics through a wet-up period in watershed 10 of the H. J. Andrews Experimental Forest in the western Cascades of Oregon where...

40 CFR Table 5 to Subpart Ppp of... - Process Vents From Batch Unit Operations-Monitoring, Recordkeeping, and Reporting Requirements

Code of Federal Regulations, 2011 CFR

2011-07-01

... Carbon Adsorber f Total regeneration stream mass or volumetric flow during carbon bed regeneration cycle(s), and 1. Record of total regeneration stream mass or volumetric flow for each carbon bed regeneration cycle.2. Record and report the total regeneration stream mass or volumetric flow during each...

40 CFR Table 5 to Subpart Ppp of... - Process Vents From Batch Unit Operations-Monitoring, Recordkeeping, and Reporting Requirements

Code of Federal Regulations, 2012 CFR

2012-07-01

... Carbon Adsorber f Total regeneration stream mass or volumetric flow during carbon bed regeneration cycle(s), and 1. Record of total regeneration stream mass or volumetric flow for each carbon bed regeneration cycle.2. Record and report the total regeneration stream mass or volumetric flow during each...

40 CFR Table 5 to Subpart Ppp of... - Process Vents From Batch Unit Operations-Monitoring, Recordkeeping, and Reporting Requirements

Code of Federal Regulations, 2010 CFR

2010-07-01

... Carbon Adsorber f Total regeneration stream mass or volumetric flow during carbon bed regeneration cycle(s), and 1. Record of total regeneration stream mass or volumetric flow for each carbon bed regeneration cycle.2. Record and report the total regeneration stream mass or volumetric flow during each...

Short-term stream water temperature observations permit rapid assessment of potential climate change impacts

Treesearch

Peter Caldwell; Catalina Segura; Shelby Gull Laird; Ge Sun; Steven G. McNulty; Maria Sandercock; Johnny Boggs; James M. Vose

2015-01-01

Assessment of potential climate change impacts on stream water temperature (Ts) across large scales remains challenging for resource managers because energy exchange processes between the atmosphere and the stream environment are complex and uncertain, and few long-term datasets are available to evaluate changes over time. In this study, we...

40 CFR 63.143 - Process wastewater provisions-inspections and monitoring of operations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... separator that receives, manages, or treats a Group 1 wastewater stream, a residual removed from a Group 1 wastewater stream, a recycled Group 1 wastewater stream, or a recycled residual removed from a Group 1... of this subpart. (b) For each design steam stripper and biological treatment unit used to comply with...

Scale-dependent genetic structure of the Idaho giant salamander (Dicamptodon aterrimus) in stream networks

Treesearch

Lindy B. Mullen; H. Arthur Woods; Michael K. Schwartz; Adam J. Sepulveda; Winsor H. Lowe

2010-01-01

The network architecture of streams and rivers constrains evolutionary, demographic and ecological processes of freshwater organisms. This consistent architecture also makes stream networks useful for testing general models of population genetic structure and the scaling of gene flow. We examined genetic structure and gene flow in the facultatively paedomorphic Idaho...

Controls on patterns of coarse organic particle retention in headwater streams

Treesearch

E. N. Jack Brookshire; Kathleen A. Dwire

2003-01-01

Organic matter retention is an integral ecosystem process affecting C and nutrient dynamics and biota in streams. Influences of discharge (Q), reach-scale channel form, and riparian vegetation on coarse particulate organic matter (CPOM) retention were analyzed in 2 headwater streams in northeastern Oregon. Ginkgo biloba leaves were released in coniferous forest reaches...

Continental hydrosystem modelling: the concept of nested stream-aquifer interfaces

NASA Astrophysics Data System (ADS)

Flipo, N.; Mouhri, A.; Labarthe, B.; Biancamaria, S.; Rivière, A.; Weill, P.

2014-08-01

Coupled hydrological-hydrogeological models, emphasising the importance of the stream-aquifer interface, are more and more used in hydrological sciences for pluri-disciplinary studies aiming at investigating environmental issues. Based on an extensive literature review, stream-aquifer interfaces are described at five different scales: local [10 cm-~10 m], intermediate [~10 m-~1 km], watershed [10 km2-~1000 km2], regional [10 000 km2-~1 M km2] and continental scales [>10 M km2]. This led us to develop the concept of nested stream-aquifer interfaces, which extends the well-known vision of nested groundwater pathways towards the surface, where the mixing of low frequency processes and high frequency processes coupled with the complexity of geomorphological features and heterogeneities creates hydrological spiralling. This conceptual framework allows the identification of a hierarchical order of the multi-scale control factors of stream-aquifer hydrological exchanges, from the larger scale to the finer scale. The hyporheic corridor, which couples the river to its 3-D hyporheic zone, is then identified as the key component for scaling hydrological processes occurring at the interface. The identification of the hyporheic corridor as the support of the hydrological processes scaling is an important step for the development of regional studies, which is one of the main concerns for water practitioners and resources managers. In a second part, the modelling of the stream-aquifer interface at various scales is investigated with the help of the conductance model. Although the usage of the temperature as a tracer of the flow is a robust method for the assessment of stream-aquifer exchanges at the local scale, there is a crucial need to develop innovative methodologies for assessing stream-aquifer exchanges at the regional scale. After formulating the conductance model at the regional and intermediate scales, we address this challenging issue with the development of an iterative modelling methodology, which ensures the consistency of stream-aquifer exchanges between the intermediate and regional scales. Finally, practical recommendations are provided for the study of the interface using the innovative methodology MIM (Measurements-Interpolation-Modelling), which is graphically developed, scaling in space the three pools of methods needed to fully understand stream-aquifer interfaces at various scales. In the MIM space, stream-aquifer interfaces that can be studied by a given approach are localised. The efficiency of the method is demonstrated with two examples. The first one proposes an upscaling framework, structured around river reaches of ~10-100 m, from the local to the watershed scale. The second example highlights the usefulness of space borne data to improve the assessment of stream-aquifer exchanges at the regional and continental scales. We conclude that further developments in modelling and field measurements have to be undertaken at the regional scale to enable a proper modelling of stream-aquifer exchanges from the local to the continental scale.

A Hyporheic Mesocosm Experiment: Influence of Quantity and Quality of stream-source DOC on Rates of Hyporheic Metabolism

NASA Astrophysics Data System (ADS)

Serchan, S. P.; Wondzell, S. M.; Haggerty, R.; Pennington, R.; Feris, K. P.; Sanfilippo, A. R.; Reeder, W. J.; Tonina, D.

2016-12-01

Hyporheic zone biogeochemical processes can influence stream water chemistry. Some estimates show that 50-90% stream water CO2 is produced in the hyporheic zone through heterotrophic metabolism of organic matter, usually supplied from the stream as dissolved organic carbon (DOC). Preliminary results from our well network at the HJ Andrews WS1, indicate that dissolved inorganic carbon (DIC) is 1.5-2 times higher in the hyporheic zone than in stream water. Conversely, DOC (mg/L) is 1.5 times higher in stream water than in the hyporheic zone throughout the year. Overall, the hyporheic zone appears to be a net source of DIC. However, the increase in DIC along hyporheic flow paths is approximately 10-times greater than the loss of DOC, suggesting that metabolism of buried particulate organic carbon (POC) is a major source of organic carbon for microbial metabolism. However, we cannot completely rule out alternative sources of DIC, especially those originating in the overlying riparian soil, because hyporheic processes are difficult to isolate in well networks. To study hyporheic zone biogeochemical processes, particularly the transformation of organic carbon to inorganic carbon species, we designed and built six replicate 2-m long hyporheic mesocosms in which we are conducting DOC amendment experiments. We examine the role of DOC quality and quantity on hyporheic respiration by injecting labile (acetate) and refractory (fulvic acid) organic carbon and comparing rates of O2 consumption, DOC loss, and DIC gains against a control. We expect that stream source DOC is limiting in this small headwater stream, forcing hyporheic metabolism to rely on buried POC. However, the long burial time of POC suggests it is likely of low quality so that supplying labile DOC in stream water should shift hyporheic metabolism away from POC rather than increase the overall rate of metabolism. Future experiments will examine natural sources of DOC (stream periphyton, leaf, and soil humic horizon leachates), the breakdown of wood buried in the hyporheic zone, and the role of temperature and nutrients in controlling the rate at which buried POC is metabolized.

Fuel and oxygen addition for metal smelting or refining process

DOEpatents

Schlichting, Mark R.

1994-01-01

A furnace 10 for smelting iron ore and/or refining molten iron 20 is equipped with an overhead pneumatic lance 40, through which a center stream of particulate coal 53 is ejected at high velocity into a slag layer 30. An annular stream of nitrogen or argon 51 enshrouds the coal stream. Oxygen 52 is simultaneously ejected in an annular stream encircling the inert gas stream 51. The interposition of the inert gas stream between the coal and oxygen streams prevents the volatile matter in the coal from combusting before it reaches the slag layer. Heat of combustion is thus more efficiently delivered to the slag, where it is needed to sustain the desired reactions occurring there. A second stream of lower velocity oxygen can be delivered through an outermost annulus 84 to react with carbon monoxide gas rising from slag layer 30, thereby adding still more heat to the furnace.

Fuel and oxygen addition for metal smelting or refining process

DOEpatents

Schlichting, M.R.

1994-11-22

A furnace for smelting iron ore and/or refining molten iron is equipped with an overhead pneumatic lance, through which a center stream of particulate coal is ejected at high velocity into a slag layer. An annular stream of nitrogen or argon enshrouds the coal stream. Oxygen is simultaneously ejected in an annular stream encircling the inert gas stream. The interposition of the inert gas stream between the coal and oxygen streams prevents the volatile matter in the coal from combusting before it reaches the slag layer. Heat of combustion is thus more efficiently delivered to the slag, where it is needed to sustain the desired reactions occurring there. A second stream of lower velocity oxygen can be delivered through an outermost annulus to react with carbon monoxide gas rising from slag layer, thereby adding still more heat to the furnace. 7 figs.

Effect of multi-stream heat exchanger on performance of natural gas liquefaction with mixed refrigerant

NASA Astrophysics Data System (ADS)

Chang, Ho-Myung; Lim, Hye Su; Choe, Kun Hyung

2012-12-01

A thermodynamic study is carried out to investigate the effect of multi-stream heat exchanger on the performance of natural gas (NG) liquefaction with mixed refrigerant (MR). A cold stream (low-pressure MR) is in thermal contact with opposite flow of two hot streams (high-pressure MR and NG feed) at the same time. In typical process simulation with commercial software (such as Aspen HYSYS®), the liquefaction performance is estimated with a method of minimum temperature approach, simply assuming that two hot streams have the same temperature. In this study, local energy balance equations are rigorously solved with temperature-dependent properties of MR and NG feed, and are linked to the thermodynamic cycle analysis. The figure of merit (FOM) is quantitatively examined in terms of UA (the product of overall heat transfer coefficient and heat exchange area) between respective streams. In a single-stage MR process, it is concluded that the temperature profile from HYSYS is difficult to realize in practice, and the FOM value from HYSYS is an over-estimate, but can be closely achieved with a proper heat-exchanger design. It is also demonstrated that there exists a unique optimal ratio in three UA's, and no direct heat exchanger between hot streams is recommended.

Ecological effects on streams from forest fertilization; literature review and conceptual framework for future study in the western Cascades

USGS Publications Warehouse

Anderson, Chauncey W.

2002-03-19

Studies of the responses of stream biota to fertilization have been rare and have targeted either immediate, toxicity-based responses or used methods insensitive to ongoing ecological processes. This report reviews water-quality studies following forest fertilizations, emphasizing Cascade streams in the Pacific Northwest and documented biological responses in those streams. A conceptual model predicting potential ecological response to fertilization, which includes effects on algal growth and primary production, is presented. In this model, applied fertilizer nitrogen reaching streams is mostly exported during winter. However, some nitrogen retained in soils or stream and riparian areas may become available to aquatic biota during spring and summer. Biological responses may be minimal in small streams nearest to application because of light limitation, but may be elevated downstream where light is sufficient to allow algal growth. Ultimately, algal response could be greatest in downstream reaches, although ambient nutrient concentrations remain low due to uptake and benthic nutrient recycling. Ground-water flow paths and hyporheic processing could be critical in determining the fate of applied nitrogen. A framework is provided for testing this response in the Little River watershed, a tributary to the North Umpqua River, Oregon, at basic and intensive levels of investigation.

Exploring inter-frame correlation analysis and wavelet-domain modeling for real-time caption detection in streaming video

NASA Astrophysics Data System (ADS)

Li, Jia; Tian, Yonghong; Gao, Wen

2008-01-01

In recent years, the amount of streaming video has grown rapidly on the Web. Often, retrieving these streaming videos offers the challenge of indexing and analyzing the media in real time because the streams must be treated as effectively infinite in length, thus precluding offline processing. Generally speaking, captions are important semantic clues for video indexing and retrieval. However, existing caption detection methods often have difficulties to make real-time detection for streaming video, and few of them concern on the differentiation of captions from scene texts and scrolling texts. In general, these texts have different roles in streaming video retrieval. To overcome these difficulties, this paper proposes a novel approach which explores the inter-frame correlation analysis and wavelet-domain modeling for real-time caption detection in streaming video. In our approach, the inter-frame correlation information is used to distinguish caption texts from scene texts and scrolling texts. Moreover, wavelet-domain Generalized Gaussian Models (GGMs) are utilized to automatically remove non-text regions from each frame and only keep caption regions for further processing. Experiment results show that our approach is able to offer real-time caption detection with high recall and low false alarm rate, and also can effectively discern caption texts from the other texts even in low resolutions.

Use of continuous monitoring to assess stream nitrate flux and transformation patterns.

PubMed

Jones, Christopher; Kim, Sea-Won; Schilling, Keith

2017-01-01

Delivery of nitrogen from farmed fields to the stream network is an ongoing water quality issue in central North America and other parts of the world. Although fertilization and other farming practices have been refined to produce environmental improvements, stemming loss of nitrogen, especially in the soluble nitrate form, is a problem that has seemingly defied solution. The Iowa Nutrient Reduction Strategy is a policy initiative designed to implement conservation and other farm management practices to produce reductions in nitrate loading. The strategy does not focus on how the streams themselves may or may not be processing nitrogen and reducing downstream loading. We used continuous high-frequency nitrate and discharge monitoring over 3 years at two sites separated by 18 km in a low-order, agricultural stream in eastern Iowa to estimate how nitrogen is processed, and whether or not these processes are reducing downstream loading. We conclude that the upstream to downstream nitrate concentration decline between the two sites was not driven by denitrification. These data also show that nitrate concentrations are closely coupled to discharge during periods of adequate moisture, but decoupling of concentration from discharge occurs during dry periods. This decoupling is a possible indicator of in-stream nitrate processing. Finally, nitrate concentrations are likely diluted by water sourced from non-row crop land covers in the lower reaches of the watershed.

Data Streaming for Metabolomics: Accelerating Data Processing and Analysis from Days to Minutes

PubMed Central

2016-01-01

The speed and throughput of analytical platforms has been a driving force in recent years in the “omics” technologies and while great strides have been accomplished in both chromatography and mass spectrometry, data analysis times have not benefited at the same pace. Even though personal computers have become more powerful, data transfer times still represent a bottleneck in data processing because of the increasingly complex data files and studies with a greater number of samples. To meet the demand of analyzing hundreds to thousands of samples within a given experiment, we have developed a data streaming platform, XCMS Stream, which capitalizes on the acquisition time to compress and stream recently acquired data files to data processing servers, mimicking just-in-time production strategies from the manufacturing industry. The utility of this XCMS Online-based technology is demonstrated here in the analysis of T cell metabolism and other large-scale metabolomic studies. A large scale example on a 1000 sample data set demonstrated a 10 000-fold time savings, reducing data analysis time from days to minutes. Further, XCMS Stream has the capability to increase the efficiency of downstream biochemical dependent data acquisition (BDDA) analysis by initiating data conversion and data processing on subsets of data acquired, expanding its application beyond data transfer to smart preliminary data decision-making prior to full acquisition. PMID:27983788

Data streaming for metabolomics: Accelerating data processing and analysis from days to minutes

DOE PAGES

Montenegro-Burke, J. Rafael; Aisporna, Aries E.; Benton, H. Paul; ...

2016-12-16

The speed and throughput of analytical platforms has been a driving force in recent years in the “omics” technologies and while great strides have been accomplished in both chromatography and mass spectrometry, data analysis times have not benefited at the same pace. Even though personal computers have become more powerful, data transfer times still represent a bottleneck in data processing because of the increasingly complex data files and studies with a greater number of samples. To meet the demand of analyzing hundreds to thousands of samples within a given experiment, we have developed a data streaming platform, XCMS Stream, whichmore » capitalizes on the acquisition time to compress and stream recently acquired data files to data processing servers, mimicking just-in-time production strategies from the manufacturing industry. The utility of this XCMS Online-based technology is demonstrated here in the analysis of T cell metabolism and other large-scale metabolomic studies. A large scale example on a 1000 sample data set demonstrated a 10 000-fold time savings, reducing data analysis time from days to minutes. Here, XCMS Stream has the capability to increase the efficiency of downstream biochemical dependent data acquisition (BDDA) analysis by initiating data conversion and data processing on subsets of data acquired, expanding its application beyond data transfer to smart preliminary data decision-making prior to full acquisition.« less

Opposing dorsal/ventral stream dynamics during figure-ground segregation.

PubMed

Wokke, Martijn E; Scholte, H Steven; Lamme, Victor A F

2014-02-01

The visual system has been commonly subdivided into two segregated visual processing streams: The dorsal pathway processes mainly spatial information, and the ventral pathway specializes in object perception. Recent findings, however, indicate that different forms of interaction (cross-talk) exist between the dorsal and the ventral stream. Here, we used TMS and concurrent EEG recordings to explore these interactions between the dorsal and ventral stream during figure-ground segregation. In two separate experiments, we used repetitive TMS and single-pulse TMS to disrupt processing in the dorsal (V5/HMT⁺) and the ventral (lateral occipital area) stream during a motion-defined figure discrimination task. We presented stimuli that made it possible to differentiate between relatively low-level (figure boundary detection) from higher-level (surface segregation) processing steps during figure-ground segregation. Results show that disruption of V5/HMT⁺ impaired performance related to surface segregation; this effect was mainly found when V5/HMT⁺ was perturbed in an early time window (100 msec) after stimulus presentation. Surprisingly, disruption of the lateral occipital area resulted in increased performance scores and enhanced neural correlates of surface segregation. This facilitatory effect was also mainly found in an early time window (100 msec) after stimulus presentation. These results suggest a "push-pull" interaction in which dorsal and ventral extrastriate areas are being recruited or inhibited depending on stimulus category and task demands.

Data Streaming for Metabolomics: Accelerating Data Processing and Analysis from Days to Minutes.

PubMed

Montenegro-Burke, J Rafael; Aisporna, Aries E; Benton, H Paul; Rinehart, Duane; Fang, Mingliang; Huan, Tao; Warth, Benedikt; Forsberg, Erica; Abe, Brian T; Ivanisevic, Julijana; Wolan, Dennis W; Teyton, Luc; Lairson, Luke; Siuzdak, Gary

2017-01-17

The speed and throughput of analytical platforms has been a driving force in recent years in the "omics" technologies and while great strides have been accomplished in both chromatography and mass spectrometry, data analysis times have not benefited at the same pace. Even though personal computers have become more powerful, data transfer times still represent a bottleneck in data processing because of the increasingly complex data files and studies with a greater number of samples. To meet the demand of analyzing hundreds to thousands of samples within a given experiment, we have developed a data streaming platform, XCMS Stream, which capitalizes on the acquisition time to compress and stream recently acquired data files to data processing servers, mimicking just-in-time production strategies from the manufacturing industry. The utility of this XCMS Online-based technology is demonstrated here in the analysis of T cell metabolism and other large-scale metabolomic studies. A large scale example on a 1000 sample data set demonstrated a 10 000-fold time savings, reducing data analysis time from days to minutes. Further, XCMS Stream has the capability to increase the efficiency of downstream biochemical dependent data acquisition (BDDA) analysis by initiating data conversion and data processing on subsets of data acquired, expanding its application beyond data transfer to smart preliminary data decision-making prior to full acquisition.

Evaluating the fate of six common pharmaceuticals using a reactive transport model: insights from a stream tracer test.

PubMed

Riml, Joakim; Wörman, Anders; Kunkel, Uwe; Radke, Michael

2013-08-01

Quantitative information regarding the capacity of rivers to self-purify pharmaceutical residues is limited. To bridge this knowledge gap, we present a methodology for quantifying the governing processes affecting the fate of pharmaceuticals in streaming waters and, especially, to evaluate their relative significance for tracer observations. A tracer test in Säva Brook, Sweden was evaluated using a coupled physical-biogeochemical model framework containing surface water transport together with a representation of transient storage in slow/immobile zones of the stream, which are presumably important for the retention and attenuation of pharmaceuticals. To assess the key processes affecting the environmental fate of the compounds, we linked the uncertainty estimates of the reaction rate coefficients to the relative influence of transformation and sorption that occurred in different stream environments. The hydrological and biogeochemical contributions to the fate of the pharmaceuticals were decoupled, and the results indicate a moderate hydrological retention in the hyporheic zone as well as in the densely vegetated parts of the stream. Biogeochemical reactions in these transient storage zones further affected the fate of the pharmaceuticals, and we found that sorption was the key process for bezafibrate, metoprolol, and naproxen, while primary transformation was the most important process for clofibric acid and ibuprofen. Conversely, diclofenac was not affected by sorption or transformation. Copyright © 2013 Elsevier B.V. All rights reserved.

Process for separating carbon dioxide from flue gas using sweep-based membrane separation and absorption steps

DOEpatents

Wijmans, Johannes G.; Baker, Richard W.; Merkel, Timothy C.

2012-08-21

A gas separation process for treating flue gases from combustion processes, and combustion processes including such gas separation. The invention involves routing a first portion of the flue gas stream to be treated to an absorption-based carbon dioxide capture step, while simultaneously flowing a second portion of the flue gas across the feed side of a membrane, flowing a sweep gas stream, usually air, across the permeate side, then passing the permeate/sweep gas to the combustor.

High temperature desulfurization of synthesis gas

DOEpatents

Najjar, Mitri S.; Robin, Allen M.

1989-01-01

The hot process gas stream from the partial oxidation of sulfur-containing heavy liquid hydrocarbonaceous fuel and/or sulfur-containing solid carbonaceous fuel comprising gaseous mixtures of H.sub.2 +CO, sulfur-containing gases, entrained particulate carbon, and molten slag is passed through the unobstructed central passage of a radiant cooler where the temperature is reduced to a temperature in the range of about 1800.degree. F. to 1200.degree. F. From about 0 to 95 wt. % of the molten slag and/or entrained material may be removed from the hot process gas stream prior to the radiant cooler with substantially no reduction in temperature of the process gas stream. In the radiant cooler, after substantially all of the molten slag has solidified, the sulfur-containing gases are contacted with a calcium-containing material to produce calcium sulfide. A partially cooled stream of synthesis gas, reducing gas, or fuel gas containing entrained calcium sulfide particulate matter, particulate carbon, and solidified slag leaves the radiant cooler containing a greatly reduced amount of sulfur-containing gases.

Producing methane, methanol and electricity from organic waste of fermentation reaction using novel microbes.

PubMed

Dhiman, Saurabh Sudha; Shrestha, Namita; David, Aditi; Basotra, Neha; Johnson, Glenn R; Chadha, Bhupinder S; Gadhamshetty, Venkataramana; Sani, Rajesh K

2018-06-01

Residual solid and liquid streams from the one-pot CRUDE (Conversion of Raw and Untreated Disposal into Ethanol) process were treated with two separate biochemical routes for renewable energy transformation. The solid residual stream was subjected to thermophilic anaerobic digestion (TAD), which produced 95 ± 7 L methane kg -1 volatile solid with an overall energy efficiency of 12.9 ± 1.7%. A methanotroph, Methyloferula sp., was deployed for oxidation of mixed TAD biogas into methanol. The residual liquid stream from CRUDE process was used in a Microbial Fuel Cell (MFC) to produce electricity. Material balance calculations confirmed the integration of biochemical routes (i.e. CRUDE, TAD, and MFC) for developing a sustainable approach of energy regeneration. The current work demonstrates the utilization of different residual streams originated after food waste processing to release minimal organic load to the environment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Metathesis process for preparing an alpha, omega-functionalized olefin

DOEpatents

Burdett, Kenneth A.; Mokhtarzadeh, Morteza; Timmers, Francis J.

2010-10-12

A cross-metathesis process for preparing an .alpha.,.omega.-functionalized olefin, such as methyl 9-decenoate, and an .alpha.-olefin having three or more carbon atoms, such as 1-decene. The process involves contacting in a first reaction zone an .alpha.-functionalized internal olefin, such as methyl oleate, and an .alpha.-olefinic monomer having three or more carbon atoms, such as 1-decene, with a first metathesis catalyst to prepare an effluent stream containing the .alpha.,.omega.-functionalized olefin, such as methyl 9-decenoate, an unfunctionalized internal olefin, such as 9-octadecene, unconverted reactant olefins, and optionally, an .alpha.,.omega.-difunctionalized internal olefinic dimer, such as dimethyl 9-octadecen-1,18-dioate; separating said effluent streams; then contacting in a second reaction zone the unfunctionalized internal olefin with ethylene in the presence of a second metathesis catalyst to obtain a second product effluent containing the .alpha.-olefinic monomer having three or more carbon atoms; and cycling a portion of the .alpha.-olefinic monomer stream(s) to the first zone.

Testing the dual-pathway model for auditory processing in human cortex.

PubMed

Zündorf, Ida C; Lewald, Jörg; Karnath, Hans-Otto

2016-01-01

Analogous to the visual system, auditory information has been proposed to be processed in two largely segregated streams: an anteroventral ("what") pathway mainly subserving sound identification and a posterodorsal ("where") stream mainly subserving sound localization. Despite the popularity of this assumption, the degree of separation of spatial and non-spatial auditory information processing in cortex is still under discussion. In the present study, a statistical approach was implemented to investigate potential behavioral dissociations for spatial and non-spatial auditory processing in stroke patients, and voxel-wise lesion analyses were used to uncover their neural correlates. The results generally provided support for anatomically and functionally segregated auditory networks. However, some degree of anatomo-functional overlap between "what" and "where" aspects of processing was found in the superior pars opercularis of right inferior frontal gyrus (Brodmann area 44), suggesting the potential existence of a shared target area of both auditory streams in this region. Moreover, beyond the typically defined posterodorsal stream (i.e., posterior superior temporal gyrus, inferior parietal lobule, and superior frontal sulcus), occipital lesions were found to be associated with sound localization deficits. These results, indicating anatomically and functionally complex cortical networks for spatial and non-spatial auditory processing, are roughly consistent with the dual-pathway model of auditory processing in its original form, but argue for the need to refine and extend this widely accepted hypothesis. Copyright © 2015 Elsevier Inc. All rights reserved.

Method and apparatus of prefetching streams of varying prefetch depth

DOEpatents

Gara, Alan [Mount Kisco, NY; Ohmacht, Martin [Yorktown Heights, NY; Salapura, Valentina [Chappaqua, NY; Sugavanam, Krishnan [Mahopac, NY; Hoenicke, Dirk [Seebruck-Seeon, DE

2012-01-24

Method and apparatus of prefetching streams of varying prefetch depth dynamically changes the depth of prefetching so that the number of multiple streams as well as the hit rate of a single stream are optimized. The method and apparatus in one aspect monitor a plurality of load requests from a processing unit for data in a prefetch buffer, determine an access pattern associated with the plurality of load requests and adjust a prefetch depth according to the access pattern.

Occurrence and Distribution of Ordinary High Water Mark (OHWM) Indicators in Non-Perennial Streams in the Western Mountains, Valleys, and Coast Region of the United States

DTIC Science & Technology

2014-08-01

1 Common hydrogeomorphic units that form in stream systems in response to spatially and temporally varying hydrologic and geomorphic processes... geomorphic , and vegetative indica- tors for use in OHWM delineations in arid streams and categorized their typical landscape positions with respect...the presence of a bed and banks. Hydrogeomorphic units are distinct macro- scale geomorphic features formed within stream systems in response to

The role of chemical and physical watershed processes in the remediation of AMD impacted streams

NASA Astrophysics Data System (ADS)

Lopez, D. A. L.; Kruse, N.; Bowman, J.

2016-12-01

Thousands of miles of streams in the United States are impacted by acid mine drainage (AMD) produced by the exploitation of metal and coal mines. Several methods of remediation are used to improve the water quality and recover the diversity in the aquatic life. One of these methods is the addition of alkaline materials to the stream to neutralize the water, precipitate minerals of heavy metals, and rise the pH. Parameters that are usually considered to determine the load of alkalinity to remediate the water include the acidity and flow of the source(s), and concentration of heavy metals. However, recent studies in AMD remediated streams in SE Ohio suggest that the evolution of the water and sediment chemistry along the stream after remediation is also important, and than that evolution depends no only in the added alkalinity but also in the physical and chemical characteristics of the impacted stream. Retention of precipitated fine-grained sediments is important to improve the physical environment for the aquatic life downstream. If sediment retention ponds cannot be constructed, the occurrence of areas where sediments can be deposited and stored is determined by the topographic gradient of the stream. A detailed high-resolution profile of the stream should be constructed to identify regions where the sediments can be retained. The addition of water, dissolved and suspended matter from tributaries to the main stem should also be considered. Tributaries can provide additional alkalinity or acidity to the stream helping to the remediation process or making it more difficult. Groundwater discharges to the stream can also provide either additional alkalinity or acidity to the stream, affecting the chemical budget. These additions from surface and/or groundwater can play an important role in stream recovery. A budget of alkalinity, acidity, and other chemical species along the impacted stream can provide important information to predict the effect of alkaline additions in stream recovery. Studies prior to remediation should not concentrate in the source alone but to consider the whole watershed impacted by the AMD sources.

Contaminants in urban waters—Science capabilities of the U.S. Geological Survey

USGS Publications Warehouse

Jastram, John D.; Hyer, Kenneth E.

2016-04-29

Streams and estuaries with urban watersheds commonly exhibit increased streamflow and decreased base flow; diminished stream-channel stability; excessive amounts of contaminants such as pesticides, metals, industrial and municipal waste, and combustion products; and alterations to biotic community structure. Collectively, these detrimental effects have been termed the “urban-stream syndrome.” Water-resource managers seek to lessen the effects on receiving water bodies of new urban development and remediate the effects in areas of existing urbanization. Similarly, the scientific community has produced extensive research on these topics, with researchers from the U.S. Geological Survey (USGS) leading many studies of urban streams and the processes responsible for the urban-stream syndrome. Increasingly, USGS studies are evaluating the effects of management and restoration activities to better understand how urban waters respond to the implementation of management practices. The USGS has expertise in collecting and interpreting data for many physical, chemical, and ecological processes in urban waters and, thus, provides holistic assessments to inform managers of urban water resources.

Total Mercury, Methylmercury, Methylmercury Production Potential, and Ancillary Streambed-Sediment and Pore-Water Data for Selected Streams in Oregon, Wisconsin, and Florida, 2003-04

USGS Publications Warehouse

Marvin-DiPasquale, Mark C.; Lutz, Michelle A.; Krabbenhoft, David P.; Aiken, George R.; Orem, William H.; Hall, Britt D.; DeWild, John F.; Brigham, Mark E.

2008-01-01

Mercury contamination of aquatic ecosystems is an issue of national concern, affecting both wildlife and human health. Detailed information on mercury cycling and food-web bioaccumulation in stream settings and the factors that control these processes is currently limited. In response, the U.S. Geological Survey (USGS) National Water-Quality Assessment Program (NAWQA) conducted detailed studies from 2002 to 2006 on various media to enhance process-level understanding of mercury contamination, biogeochemical cycling, and trophic transfer. Eight streams were sampled for this study: two streams in Oregon, and three streams each in Wisconsin and Florida. Streambed-sediment and pore-water samples were collected between February 2003 and September 2004. This report summarizes the suite of geochemical and microbial constituents measured, the analytical methods used, and provides the raw data in electronic form for both bed-sediment and pore-water media associated with this study.

Computing Strongly Connected Components in the Streaming Model

NASA Astrophysics Data System (ADS)

Laura, Luigi; Santaroni, Federico

In this paper we present the first algorithm to compute the Strongly Connected Components of a graph in the datastream model (W-Stream), where the graph is represented by a stream of edges and we are allowed to produce intermediate output streams. The algorithm is simple, effective, and can be implemented with few lines of code: it looks at each edge in the stream, and selects the appropriate action with respect to a tree T, representing the graph connectivity seen so far. We analyze the theoretical properties of the algorithm: correctness, memory occupation (O(n logn)), per item processing time (bounded by the current height of T), and number of passes (bounded by the maximal height of T). We conclude by presenting a brief experimental evaluation of the algorithm against massive synthetic and real graphs that confirms its effectiveness: with graphs with up to 100M nodes and 4G edges, only few passes are needed, and millions of edges per second are processed.

What puts the how in where? Tool use and the divided visual streams hypothesis.

PubMed

Frey, Scott H

2007-04-01

An influential theory suggests that the dorsal (occipito-parietal) visual stream computes representations of objects for purposes of guiding actions (determining 'how') independently of ventral (occipito-temporal) stream processes supporting object recognition and semantic processing (determining 'what'). Yet, the ability of the dorsal stream alone to account for one of the most common forms of human action, tool use, is limited. While experience-dependent modifications to existing dorsal stream representations may explain simple tool use behaviors (e.g., using sticks to extend reach) found among a variety of species, skillful use of manipulable artifacts (e.g., cups, hammers, pencils) requires in addition access to semantic representations of objects' functions and uses. Functional neuroimaging suggests that this latter information is represented in a left-lateralized network of temporal, frontal and parietal areas. I submit that the well-established dominance of the human left hemisphere in the representation of familiar skills stems from the ability for this acquired knowledge to influence the organization of actions within the dorsal pathway.

Dissociation and Convergence of the Dorsal and Ventral Visual Streams in the Human Prefrontal Cortex

PubMed Central

Takahashi, Emi; Ohki, Kenichi; Kim, Dae-Shik

2012-01-01

Visual information is largely processed through two pathways in the primate brain: an object pathway from the primary visual cortex to the temporal cortex (ventral stream) and a spatial pathway to the parietal cortex (dorsal stream). Whether and to what extent dissociation exists in the human prefrontal cortex (PFC) has long been debated. We examined anatomical connections from functionally defined areas in the temporal and parietal cortices to the PFC, using noninvasive functional and diffusion-weighted magnetic resonance imaging. The right inferior frontal gyrus (IFG) received converging input from both streams, while the right superior frontal gyrus received input only from the dorsal stream. Interstream functional connectivity to the IFG was dynamically recruited only when both object and spatial information were processed. These results suggest that the human PFC receives dissociated and converging visual pathways, and that the right IFG region serves as an integrator of the two types of information. PMID:23063444

Seasonal and event-scale controls on dissolved organic carbon and nitrate flushing from catchments

NASA Astrophysics Data System (ADS)

Sebestyen, S. D.; Boyer, E. W.; Shanley, J. B.; Doctor, D. H.

2005-05-01

To explore terrestrial and aquatic linkages controlling nutrient dynamics in forested catchments, we collected high-frequency samples from 2002 to 2004 at the Sleepers River Research Watershed in northeastern Vermont USA. We measured DOC (dissolved organic carbon), SUVA (specific UV absorbance), nitrate, and major ion concentrations over a wide range of flow conditions. In addition, weekly samples since 1991 provide a longer term record of stream nutrient fluxes. During events, DOC concentrations increased with flow consistent with the flushing of a large reservoir of mobile organic carbon from forest soils. Higher concentrations of DOC and SUVA in the growing versus dormant season illustrated seasonal variation in sources, characteristics (i.e. reactivity), availability, and controls on the flushing response of organic matter from the landscape to streams. In contrast, stream nitrate concentrations increased with flow but only when catchments "wetted-up" after baseflow periods. Growing season stream nitrate responses were dependent on short-term antecedent moisture conditions indicating rapid depletion of the soil nitrate reservoir when source areas became hydrologically connected to streams. While the different response patterns emphasized variable source and biogeochemical controls in relation to flow patterns, coupled carbon and nitrogen biogeochemical processes were also important controls on stream nutrient fluxes. In particular, leaf fall was a critical time when reactive DOC from freshly decomposing litter fueled in-stream consumption of nitrate leading to sharp declines of stream nitrate concentrations. Our measurements highlight the importance of "hot spots" and "hot moments" of biogeochemical and hydrological processes that control stream responses. Furthermore, our work illustrates how carbon, nitrogen, and water cycles are coupled in catchments, and provides a conceptual model for future work aimed at modeling forest stream hydrochemistry at the catchment scale.

40 CFR 98.426 - Data reporting requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... flow meter in your process chain in relation to the points of CO2 stream capture, dehydration... concentration. (7) The location of the flow meter in your process chain in relation to the points of CO2 stream... meter(s) in metric tons. (iii) The total annual CO2 mass supplied in metric tons. (iv) The location of...

40 CFR 98.426 - Data reporting requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... flow meter in your process chain in relation to the points of CO2 stream capture, dehydration... concentration. (7) The location of the flow meter in your process chain in relation to the points of CO2 stream... meter(s) in metric tons. (iii) The total annual CO2 mass supplied in metric tons. (iv) The location of...

Endocrine disrupting alkylphenolic chemicals and other contaminants in wastewater treatment plant effluents, urban streams and fish in the Great Lakes Region and Upper Mississippi River

USDA-ARS?s Scientific Manuscript database

Urban streams are an integral part of the municipal wastewater treatment process by providing a point of discharge for wastewater treatment plant (WWTP) effluents and additional attenuation through dilution and transformation processes. The receiving surface waters also are a conduit for contaminan...

40 CFR 98.426 - Data reporting requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... flow meter in your process chain in relation to the points of CO2 stream capture, dehydration... concentration. (7) The location of the flow meter in your process chain in relation to the points of CO2 stream... meter(s) in metric tons. (iii) The total annual CO2 mass supplied in metric tons. (iv) The location of...

The psychophysics of Visual Motion and Global form Processing in Autism

ERIC Educational Resources Information Center

Koldewyn, Kami; Whitney, David; Rivera, Susan M.

2010-01-01

Several groups have recently reported that people with autism may suffer from a deficit in visual motion processing and proposed that these deficits may be related to a general dorsal stream dysfunction. In order to test the dorsal stream deficit hypothesis, we investigated coherent and biological motion perception as well as coherent form…

Putting newborn hearing screening on the political agenda in Belgium: local initiatives toward a community programme – a qualitative study

PubMed Central

2014-01-01

Background The Kingdon model, based on the convergence of three streams (problem, policy, and politics) and the opening of a policy window, analyses the process by which a health issue is placed on the political agenda. We used this model to document the political agenda-setting process of the newborn hearing screening programme in Belgium. Methods A qualitative study based on a document review and on semi-directed interviews was carried out. The interviews were conducted with nine people who had played a role in putting the issue in question on the political agenda, and the documents reviewed included scientific literature and internal reports and publications from the newborn hearing screening programme. The thematic analysis of the data collected was carried out on the basis of the Kingdon model’s three streams. Results The political agenda-setting of this screening programme was based on many factors. The problem stream included factors external to the context under study, such as the technological developments and the contribution of the scientific literature which led to the recommendation to provide newborn hearing screening. The two other streams (policy and politics) covered factors internal to the Belgian context. The fact that it was locally feasible with financial support, the network of doctors convinced of the need for newborn hearing screening, the drafting of various proposals, and the search for financing were all part of the policy stream. The Belgian political context and the policy opportunities concerning preventive medicine were identified as significant factors in the third stream. When these three streams converged, a policy window opened, allowing newborn hearing screening onto the political agenda and enabling the policy decision for its introduction. Conclusions The advantage of applying the Kingdon model in our approach was the ability to demonstrate the political agenda-setting process, using the three streams. This made it possible to identify the many factors involved in the process. However, the roles of the stakeholders and of the context were somewhat inexplicit in this model. PMID:24986647

Putting newborn hearing screening on the political agenda in Belgium: local initiatives toward a community programme - a qualitative study.

PubMed

Vos, Bénédicte; Lagasse, Raphaël; Levêque, Alain

2014-07-01

The Kingdon model, based on the convergence of three streams (problem, policy, and politics) and the opening of a policy window, analyses the process by which a health issue is placed on the political agenda. We used this model to document the political agenda-setting process of the newborn hearing screening programme in Belgium. A qualitative study based on a document review and on semi-directed interviews was carried out. The interviews were conducted with nine people who had played a role in putting the issue in question on the political agenda, and the documents reviewed included scientific literature and internal reports and publications from the newborn hearing screening programme. The thematic analysis of the data collected was carried out on the basis of the Kingdon model's three streams. The political agenda-setting of this screening programme was based on many factors. The problem stream included factors external to the context under study, such as the technological developments and the contribution of the scientific literature which led to the recommendation to provide newborn hearing screening. The two other streams (policy and politics) covered factors internal to the Belgian context. The fact that it was locally feasible with financial support, the network of doctors convinced of the need for newborn hearing screening, the drafting of various proposals, and the search for financing were all part of the policy stream. The Belgian political context and the policy opportunities concerning preventive medicine were identified as significant factors in the third stream. When these three streams converged, a policy window opened, allowing newborn hearing screening onto the political agenda and enabling the policy decision for its introduction. The advantage of applying the Kingdon model in our approach was the ability to demonstrate the political agenda-setting process, using the three streams. This made it possible to identify the many factors involved in the process. However, the roles of the stakeholders and of the context were somewhat inexplicit in this model.

Selecting Great Lakes streams for lampricide treatment based on larval sea lamprey surveys

USGS Publications Warehouse

Christie, Gavin C.; Adams, Jean V.; Steeves, Todd B.; Slade, Jeffrey W.; Cuddy, Douglas W.; Fodale, Michael F.; Young, Robert J.; Kuc, Miroslaw; Jones, Michael L.

2003-01-01

The Empiric Stream Treatment Ranking (ESTR) system is a data-driven, model-based, decision tool for selecting Great Lakes streams for treatment with lampricide, based on estimates from larval sea lamprey (Petromyzon marinus) surveys conducted throughout the basin. The 2000 ESTR system was described and applied to larval assessment surveys conducted from 1996 to 1999. A comparative analysis of stream survey and selection data was conducted and improvements to the stream selection process were recommended. Streams were selected for treatment based on treatment cost, predicted treatment effectiveness, and the projected number of juvenile sea lampreys produced. On average, lampricide treatments were applied annually to 49 streams with 1,075 ha of larval habitat, killing 15 million larval and 514,000 juvenile sea lampreys at a total cost of $5.3 million, and marginal and mean costs of $85 and $10 per juvenile killed. The numbers of juvenile sea lampreys killed for given treatment costs showed a pattern of diminishing returns with increasing investment. Of the streams selected for treatment, those with > 14 ha of larval habitat targeted 73% of the juvenile sea lampreys for 60% of the treatment cost. Suggested improvements to the ESTR system were to improve accuracy and precision of model estimates, account for uncertainty in estimates, include all potentially productive streams in the process (not just those surveyed in the current year), consider the value of all larvae killed during treatment (not just those predicted to metamorphose the following year), use lake-specific estimates of damage, and establish formal suppression targets.

Impact of redox and transport processes in a riparian wetland on stream water quality in the Fichtelgebirge region, southern Germany

NASA Astrophysics Data System (ADS)

Lischeid, G.; Kolb, A.; Alewell, C.; Paul, S.

2007-01-01

Biologically mediated redox processes in the riparian zone, like denitrification, can have substantially beneficial impacts on stream water quality. The extent of these effects, however, depends greatly on the hydrological boundary conditions. The impact of hydrological processes on a wetland's nitrogen sink capacity was investigated in a forested riparian fen which is drained by a first-order perennial stream. Here, we analysed the frequency distributions and time-series of pH and nitrogen, silica, organic carbon and oxygen concentrations in throughfall, soil solution, groundwater and stream water, and the groundwater levels and stream discharges from a 3-year period. During baseflow conditions, the stream was fed by discharging shallow, anoxic groundwater and by deep, oxic groundwater. Whereas the latter delivered considerable amounts of nitrogen (0.37 mg l-1) to the stream, the former was almost entirely depleted of nitrogen. During stormflow, near-surface runoff in the upper 30 cm soil layer bypassed the denitrifying zone and added significant amounts to the nitrogen load of the stream. Nitrate-nitrogen was close to 100% of deep groundwater and stream-water nitrogen concentration. Stream-water baseflow concentrations of nitrate, dissolved carbon and silica were about 1.6 mg l-1, 4 mg l-1 and 7.5 mg l-1 respectively, and >3 mg l-1, >10 mg l-1 and <4 mg l-1 respectively during discharge peaks. In addition to that macroscale bypassing effect, there was evidence for a corresponding microscale effect: Shallow groundwater sampled by soil suction cups indicated complete denitrification and lacked any seasonal signal of solute concentration, which was in contrast to piezometer samples from the same depth. Moreover, mean solute concentration in the piezometer samples resembled more that of suction-cup samples from shallower depth than that of the same depth. We conclude that the soil solution cups sampled to a large extent the immobile soil-water fraction. In contrast, the mobile fraction that was sampled by the piezometers exhibited substantially shorter residence time, thus being less exposed to denitrification, but predominating discharge of that layer to the stream. Consequently, assessing the nitrogen budget based on suction-cup data tended to overestimate the nitrogen consumption in the riparian wetland. These effects are likely to become more important with the increased frequency and intensity of rainstorms that are expected due to climate change. Copyright

Separation science and technology. Semiannual progress report, October 1993--March 1994

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vandegrift, G.F.; Aase, S.B.; Buchholz, B.

1997-12-01

This document reports on the work done by the Separations Science and Technology Programs of the Chemical Technology Division, Argonne National Laboratory (ANL), in the period October 1993-March 1994. This effort is mainly concerned with developing the TRUEX process for removing and concentrating actinides from acidic waste streams contaminated with transuranic (TRU) elements. The objectives of TRUEX processing are to recover valuable TRU elements and to lower disposal costs for the nonTRU waste product of the process. Other projects are underway with the objective of developing (1) evaporation technology for concentrating radioactive waste and product streams such as those generatedmore » by the TRUEX process, (2) treatment schemes for liquid wastes stored are being generated at ANL, (3) a process based on sorbing modified TRUEX solvent on magnetic beads to be used for separation of contaminants from radioactive and hazardous waste streams, and (4) a process that uses low-enriched uranium targets for production of {sup 99}Mo for nuclear medicine uses.« less

Scenario driven data modelling: a method for integrating diverse sources of data and data streams

PubMed Central

2011-01-01

Background Biology is rapidly becoming a data intensive, data-driven science. It is essential that data is represented and connected in ways that best represent its full conceptual content and allows both automated integration and data driven decision-making. Recent advancements in distributed multi-relational directed graphs, implemented in the form of the Semantic Web make it possible to deal with complicated heterogeneous data in new and interesting ways. Results This paper presents a new approach, scenario driven data modelling (SDDM), that integrates multi-relational directed graphs with data streams. SDDM can be applied to virtually any data integration challenge with widely divergent types of data and data streams. In this work, we explored integrating genetics data with reports from traditional media. SDDM was applied to the New Delhi metallo-beta-lactamase gene (NDM-1), an emerging global health threat. The SDDM process constructed a scenario, created a RDF multi-relational directed graph that linked diverse types of data to the Semantic Web, implemented RDF conversion tools (RDFizers) to bring content into the Sematic Web, identified data streams and analytical routines to analyse those streams, and identified user requirements and graph traversals to meet end-user requirements. Conclusions We provided an example where SDDM was applied to a complex data integration challenge. The process created a model of the emerging NDM-1 health threat, identified and filled gaps in that model, and constructed reliable software that monitored data streams based on the scenario derived multi-relational directed graph. The SDDM process significantly reduced the software requirements phase by letting the scenario and resulting multi-relational directed graph define what is possible and then set the scope of the user requirements. Approaches like SDDM will be critical to the future of data intensive, data-driven science because they automate the process of converting massive data streams into usable knowledge. PMID:22165854

Dorsal and ventral stream contributions to form-from-motion perception in a patient with form-from motion deficit: a case report.

PubMed

Mercier, Manuel R; Schwartz, Sophie; Spinelli, Laurent; Michel, Christoph M; Blanke, Olaf

2017-03-01

The main model of visual processing in primates proposes an anatomo-functional distinction between the dorsal stream, specialized in spatio-temporal information, and the ventral stream, processing essentially form information. However, these two pathways also communicate to share much visual information. These dorso-ventral interactions have been studied using form-from-motion (FfM) stimuli, revealing that FfM perception first activates dorsal regions (e.g., MT+/V5), followed by successive activations of ventral regions (e.g., LOC). However, relatively little is known about the implications of focal brain damage of visual areas on these dorso-ventral interactions. In the present case report, we investigated the dynamics of dorsal and ventral activations related to FfM perception (using topographical ERP analysis and electrical source imaging) in a patient suffering from a deficit in FfM perception due to right extrastriate brain damage in the ventral stream. Despite the patient's FfM impairment, both successful (observed for the highest level of FfM signal) and absent/failed FfM perception evoked the same temporal sequence of three processing states observed previously in healthy subjects. During the first period, brain source localization revealed cortical activations along the dorsal stream, currently associated with preserved elementary motion processing. During the latter two periods, the patterns of activity differed from normal subjects: activations were observed in the ventral stream (as reported for normal subjects), but also in the dorsal pathway, with the strongest and most sustained activity localized in the parieto-occipital regions. On the other hand, absent/failed FfM perception was characterized by weaker brain activity, restricted to the more lateral regions. This study shows that in the present case report, successful FfM perception, while following the same temporal sequence of processing steps as in normal subjects, evoked different patterns of brain activity. By revealing a brain circuit involving the most rostral part of the dorsal pathway, this study provides further support for neuro-imaging studies and brain lesion investigations that have suggested the existence of different brain circuits associated with different profiles of interaction between the dorsal and the ventral streams.

Solute-specific scaling of inorganic nitrogen and phosphorus uptake in streams

NASA Astrophysics Data System (ADS)

Hall, R. O., Jr.; Baker, M. A.; Rosi-Marshall, E. J.; Tank, J. L.; Newbold, J. D.

2013-11-01

Stream ecosystem processes such as nutrient cycling may vary with stream position in the network. Using a scaling approach, we examined the relationship between stream size and nutrient uptake length, which represents the mean distance that a dissolved solute travels prior to removal from the water column. Ammonium (NH4+) uptake length increased proportionally with stream size measured as specific discharge (discharge/stream width) with a scaling exponent = 1.01. In contrast, uptake lengths for nitrate (NO3-) and soluble reactive phosphorus (SRP) increased more rapidly than increases in specific discharge (scaling exponents = 1.19 for NO3- and 1.35 for SRP). Additionally, the ratio of inorganic nitrogen (N) uptake length to SRP uptake length declined with stream size; there was relatively lower demand for SRP compared to N as stream size increased. Finally, we related the scaling of uptake length with specific discharge to that of stream length using Hack's law and downstream hydraulic geometry. Ammonium uptake length increased less than proportionally with distance from the headwaters, suggesting a strong role for larger streams and rivers in regulating nutrient transport.

Interactions of solutes and streambed sediment: 2. A dynamic analysis of coupled hydrologic and chemical processes that determine solute transport

USGS Publications Warehouse

Bencala, Kenneth E.

1984-01-01

Solute transport in streams is determined by the interaction of physical and chemical processes. Data from an injection experiment for chloride and several cations indicate significant influence of solutestreambed processes on transport in a mountain stream. These data are interpreted in terms of transient storage processes for all tracers and sorption processes for the cations. Process parameter values are estimated with simulations based on coupled quasi-two-dimensional transport and first-order mass transfer sorption. Comparative simulations demonstrate the relative roles of the physical and chemical processes in determining solute transport. During the first 24 hours of the experiment, chloride concentrations were attenuated relative to expected plateau levels. Additional attenuation occurred for the sorbing cation strontium. The simulations account for these storage processes. Parameter values determined by calibration compare favorably with estimates from other studies in mountain streams. Without further calibration, the transport of potassium and lithium is adequately simulated using parameters determined in the chloride-strontium simulation and with measured cation distribution coefficients.

40 CFR Table 5 to Subpart Ppp of... - Process Vents From Batch Unit Operations-Monitoring, Recordkeeping, and Reporting Requirements

Code of Federal Regulations, 2013 CFR

2013-07-01

... collected—PR. d,e Carbon Adsorber f Total regeneration stream mass or volumetric flow during carbon bed regeneration cycle(s), and 1. Record of total regeneration stream mass or volumetric flow for each carbon bed regeneration cycle.2. Record and report the total regeneration stream mass or volumetric flow during each...

40 CFR Table 6 to Subpart Ppp of... - Process Vents From Continuous Unit Operations-Monitoring, Recordkeeping, and Reporting Requirements

Code of Federal Regulations, 2014 CFR

2014-07-01

... operating—PR. d e Carbon Adsorber f Total regeneration stream mass or volumetric flow during carbon bed regeneration cycle(s), and 1. Record of total regeneration stream mass or volumetric flow for each carbon bed regeneration cycle.2. Record and report the total regeneration stream mass or volumetric flow during each...

40 CFR Table 6 to Subpart Ppp of... - Process Vents From Continuous Unit Operations-Monitoring, Recordkeeping, and Reporting Requirements

Code of Federal Regulations, 2010 CFR

2010-07-01

... temperature established in the NCS or operating—PR. d,e Carbon Adsorber f Total regeneration stream mass or volumetric flow during carbon bed regeneration cycle(s), and 1. Record of total regeneration stream mass or volumetric flow for each carbon bed regeneration cycle.2. Record and report the total regeneration stream...

40 CFR Table 4 to Subpart G of... - Process Vents-Monitoring, Recordkeeping, and Reporting Requirements For Maintaining a TRE Index...

Code of Federal Regulations, 2014 CFR

2014-07-01

... NCS or operating permit—PR. Carbon adsorber d Total regeneration stream mass or volumetric flow during carbon bed regeneration cycle(s) [63.114(b)(3)], and 1. Record of total regeneration stream mass or volumetric flow for each carbon bed regeneration cycle.2. Record and report the total regeneration stream...