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1

Steam generator recirculating system for a pressurized water nuclear reactor  

Microsoft Academic Search

This patent describes a steam generator recirculating system for the recirculation of secondary coolant, for use with the nuclear steam supply system of a pressurized water nuclear reactor plant having at least two steam generators, main feedwater lines to each steam generator and a blowdown system for each steam generator. The system comprises: a discharge line for receipt of a

R. A. Loose; J. S. Schlonski; C. C. Steinkuhler

1987-01-01

2

Bacterial community structure in cooling water and biofilm in an industrial recirculating cooling water system.  

PubMed

Microbial fouling is a serious problem in open recirculating cooling water systems. The bacterial communities that cause it have not been fully understood. In this study, we analyzed the community structure of free-living bacteria and particle-attached bacteria in cooling water, and bacteria in biofilm collected from the wall of the water reservoir in an industrial recirculating cooling water system by construction of a 16S rRNA gene clone library. Based on amplified ribosomal DNA restriction analysis, clones of all three libraries were clustered into 45 operational taxonomic units (OTUs). Thirteen OTUs displaying 91-96% sequence similarity to a type strain might be novel bacterial species. Noted differences in community structure were observed among the three libraries. The relative species richness of the free-living bacteria in cooling water was much lower than that of particle-attached bacteria and bacteria in biofilm. The majority of the free-living bacterial community (99.0%) was Betaproteobacteria. The predominant bacteria in the particle-attached bacterial community were Alphaproteobacteria (20.5%), Betaproteobacteria (27.8%) and Planctomycetes (42.0%), while those in the biofilm bacterial community were Alphaproteobacteria (47.9%), Betaproteobacteria (11.7%), Acidobacteria (13.1%) and Gemmatimonadetes (11.3%). To control microbial fouling in industrial recirculating cooling water systems, additional physiological and ecological studies of these species will be essential. PMID:23985528

Wang, Jinmei; Liu, Min; Xiao, Huijie; Wu, Wei; Xie, Meijuan; Sun, Mengjia; Zhu, Chenglin; Li, Pengfu

2013-01-01

3

High rate algal pond treatment for water reuse in a marine fish recirculation system: Water purification and fish health  

Microsoft Academic Search

Regardless of the degree of closure of a recirculation system, effluents are produced and replacement water is needed, which limits the possibility of locating a seawater production system away from the shoreline. At the Palavas Ifremer station, in the south of France, a High Rate Algal Pond (HRAP) was operated during several years to treat the effluent from a recirculating

E. Metaxa; G. Deviller; P. Pagand; C. Alliaume; C. Casellas; J. P. Blancheton

2006-01-01

4

Design and Evaluation of Recirculating Water Systems for Maintenance and Propagation of Freshwater Mussels  

Microsoft Academic Search

A complete system for culturing, rearing, and holding juvenile and adult freshwater mussels (Unionidae) was designed and evaluated for use at hatcheries and research facilities. The system includes air delivery, water conditioning and delivery, algal culturing and automated algal feed delivery, and air-driven water-recirculating units. These systems are appropriate for holding and conditioning adult mussels for spawning, as well as

William F. Henley; Lora L. Zimmerman; Richard J. Neves; Mark R. Kidd

2001-01-01

5

DHW Recirculation System Control Strategies.  

National Technical Information Service (NTIS)

This study was the third step in a series of research projects that examined domestic hot water (DHW) issues in multi family buildings. The research analyzed the effects of varying control strategies of DHW recirculation systems in multi family buildings....

1999-01-01

6

Recurrent amoebic gill infestation in rainbow trout cultured in a semiclosed water recirculation system  

USGS Publications Warehouse

Five lots of commercially purchased juvenile rainbow trout Oncorhynchus mykiss (17-44 g) stocked in a continuous-production water recirculation system became infested with gilt amoebae. The amoebae were introduced into the recirculation system, as evidenced by their presence on gills of fish held in quarantine tanks. Based on their morphology, as seen in histological sections and by electron microscopy, the amoebae appeared to be more closely related to the family Cochliopodiidae than to other taxa of free living amoebae. Attempts to culture the amoebae in different media, at different temperatures of incubation, and in fish cell culture were not successful. Initial treatment of the recirculation system with formalin at 167 parts per million (ppm) for 1 h eliminated amoebae from the gills. Subsequent treatments of the entire system with formalin at 50-167 ppm reduced the intensity of further infestations.

Noble, A. C.; Herman, R. L.; Noga, E. J.; Bullock, G. L.

1997-01-01

7

Impact of ozonation on water quality in marine recirculation systems  

Microsoft Academic Search

Ozone (O3) is a powerful oxidant and is becoming popular in various aquaculture systems for disinfection and improving water quality by oxidation of inorganic and\\/or organic compounds. However, the use of ozone in marine-based aquaculture systems has been limited because of the potential to form bromate, which is formed during the oxidation of naturally occurring bromide by ozone. Because bromate

Martin S Tango; Graham A Gagnon

2003-01-01

8

Integration of direct contact membrane distillation and recirculating cooling water system for pure water production  

Microsoft Academic Search

A novel cleaner production technology (CPT) using waste heat for pure water production was established by integration of direct contact membrane distillation (DCMD) and traditional recirculating cooling water (RCW) process. The effect of temperature difference and flow rate of fluid between the hot and cold sides in a membrane module on the membrane flux was investigated. The results of the

Jun Wang; Bin Fan; Zhaokun Luan; Dan Qu; Xianjia Peng; Deyin Hou

2008-01-01

9

CORROSION OF COPPER IN OPEN RECIRCULATING WATER SYSTEMS  

Microsoft Academic Search

The cause of corrosion in condensers used in the Gaseous Diffusion ; Process has been investigated. The pitting of copper condenser tubes was caused ; by a combination of two independent conditions. The presence of copper oxide ; deposits on the tubes when purchased and their use with a cooling water ; containing ferrocyanide were the causes of the rapid

1959-01-01

10

High-rate algal pond treatment for water reuse in an integrated marine fish recirculating system: effect on water quality and sea bass growth  

Microsoft Academic Search

A high-rate algae pond (HRAP) was tested as a second loop of water treatment in a recirculating fish rearing system to reduce water requirements and nutrient discharge levels. Three duplicated groups of sea bass (mean initial body weight 35±11 g) were reared under different system conditions (flow-through system, recirculating system and recirculating system with HRAP) for 1 year. Fish survival

Geneviève Deviller; Catherine Aliaume; Miguel Angel Franco Nava; Claude Casellas; Jean Paul Blancheton

2004-01-01

11

Microparticles in recirculating aquaculture systems: particle size analysis of culture water from a commercial Atlantic salmon site  

Microsoft Academic Search

As part of a larger study of micro-particles in a recirculating, cold water aquaculture system for juvenile Atlantic salmon (Salmo salar), particle size analyses were carried out on the culture and makeup waters over several months followed by samples of feed stirred in water. The particle size distributions followed the power law described in [Aquacult. Eng. 19 (1999): 259] but

R. N. Patterson; K. C. Watts

2003-01-01

12

An integrated recirculating aquaculture system (RAS) for land-based fish farming: The effects on water quality and fish production  

Microsoft Academic Search

To mitigate the serious water pollution caused by the rapid expansion of the aquaculture industry in recent years, the development of improved aquaculture systems with more efficient water usage and less environmental impact has become essential. In this study, a land-based recirculating aquaculture system (RAS) was established that consisted of purification units (i.e., a primary biological pond, two parallel horizontal

Shi-Yang Zhang; Gu Li; Hui-Bi Wu; Xing-Guo Liu; Yan-Hong Yao; Ling Tao; Huang Liu

13

Exhaust gas recirculation system  

SciTech Connect

An engine exhaust gas recirculation (EGR) system is provided in which a sonic flow EGR valve is moved to open positions to establish a different constant rate of flow at each open position of the EGR valve in response to air pressure acting on a servo means secured to the valve, the air pressure force being controlled by changes in a control vacuum opposing the air pressure force and modified by an air bleed device as a function of changes in engine exhaust gas backpressure levels, to provide an EGR valve movement that varies essentially in proportion to changes in engine air flow.

Rachedi, S.H.

1983-08-30

14

The performance and impact of a bubble-wash bead filter in a recirculating green water larval culture system for delta smelt ( Hypomesus transpacificus)  

Microsoft Academic Search

Delta smelt are cultured at the UC Davis Fish Conservation and Culture Lab (FCCL) for research purposes. The culture systems used are based on recirculation technology to ensure optimum water quality for the fish at each life stage. Larval culture takes place in recirculation systems with green water to which a Nannochloropsis algal concentrate is added to maintain a turbidity

Tien-Chieh Hung; Raul H. Piedrahita

2011-01-01

15

Biofouling characteristics and identification of preponderant bacteria at different nutrient levels in batch tests of a recirculating cooling water system  

Microsoft Academic Search

Understanding the influence of nutrient levels on biofouling control is an important requirement for management strategies in a recirculating cooling water system. Nutrient limitation may be one way to control biofouling development without increasing biocide dosing. Therefore, this study was carried out to investigate the effects of nutrient levels on biofouling characteristics and to identify the preponderant bacteria in the

Fang Liu; Lu Xia; Fei Yang; Xin Chang

2011-01-01

16

Recirculating cooling water solute depletion models  

Microsoft Academic Search

Chromates have been used for years to inhibit copper corrosion in the plant Recirculating Cooling Water (RCW) system. However, chromates have become an environmental problem in recent years both in the chromate removal plant (X-616) operation and from cooling tower drift. In response to this concern, PORTS is replacing chromates with Betz Dianodic II, a combination of phosphates, BZT, and

1990-01-01

17

Combustion-gas recirculation system  

DOEpatents

A combustion-gas recirculation system has a mixing chamber with a mixing-chamber inlet and a mixing-chamber outlet. The combustion-gas recirculation system may further include a duct connected to the mixing-chamber inlet. Additionally, the combustion-gas recirculation system may include an open inlet channel with a solid outer wall. The open inlet channel may extend into the mixing chamber such that an end of the open inlet channel is disposed between the mixing-chamber inlet and the mixing-chamber outlet. Furthermore, air within the open inlet channel may be at a pressure near or below atmospheric pressure.

Baldwin, Darryl Dean (Lacon, IL) [Lacon, IL

2007-10-09

18

Effect of flow rate on water quality parameters and plant growth of water spinach (Ipomoea aquatica) in an aquaponic recirculating system  

Microsoft Academic Search

Recirculating aquaculture–hydroponic systems were designed to provide an artificial, controlled environment that optimizes the growth of fish (or other aquatic species) and soil-less plants, complete control of water quality, the production schedule and the fish product, while conserving water resources. Nutrients removal such as inorganic nitrogen and phosphate is essential for aquaculture wastewater treatment to protect receiving waters from eutrophication

Azizah Endut; Ahmad Jusoh; Nora’aini Ali; W. N. S. Wan Nik; Anuar Hassan

2009-01-01

19

Community analysis of bacterial biofilms in a simulated recirculating cooling-water system by fluorescent in situ hybridization with rRNA-targeted oligonucleotide probes  

Microsoft Academic Search

An open recirculating cooling-water system feeding a modified Robbin’s Device (MRD) with synthetic cooling water to simulate the environment of a recirculating industrial cooling-water system was set up. Both mild steel and Nylon® coupons were inserted to sample biofilms at regular intervals. The community structure was determined by in situ hybridization using fluorescently labelled 16S and 23S rRNA-targeted oligonucleotide probes

R MacDonald; V. S Brözel

2000-01-01

20

A model for predicting the quantities of dissolved inorganic nitrogen released in effluents from a sea bass ( Dicentrarchus labrax) recirculating water system  

Microsoft Academic Search

Fish excretions and the transformation of nitrogen by bacteria in the nitrifying biofilter are two of the main sources of dissolved inorganic nitrogen (DIN) in fish farms that use recirculating water systems. In this study, the DIN concentration in an experimental Dicentrarchus labrax aquaculture system was calculated using empirical sub-models for fish growth, ingested food and water replacement. The specific

Pascal Pagand; Jean Paul Blancheton; Claude Casellas

2000-01-01

21

Fundamental Aspects of Ozone Chemistry in Recirculating Cooling Water Systems — Data Evaluation Needs  

Microsoft Academic Search

Proposed uses of ozone for stand-alone cooling water treatment raise critical questions as to what happens chemically. These questions are of more significance to industrial cooling water systems, which typically have higher temperatures and cooling ranges than do comfort cooling systems. When applying ozone to cooling waters, it is very important for the user to understand many fundamental aspects of

Rip G. Rice; J. Fred Wilkes

1992-01-01

22

Diseases encountered in rainbow trout cultured in recirculating systems  

Microsoft Academic Search

Recirculating systems create unique environments for fish culture which may provide favorable conditions for disease occurrence or the reproduction of opportunistic microorganisms. Stressful conditions in recirculating systems, such as poor water quality or high stocking densities in the culture tanks, may contribute to disease outbreaks. Non-infectious problems, including high levels of ammonia, nitrites, carbon dioxide, suspended solids, or ozone residual

Alicia C. Noble; Steven T. Summerfelt

1996-01-01

23

Preoperational test report, recirculation condenser cooling systems  

SciTech Connect

This represents a preoperational test report for Recirculation Condenser Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The four system provide condenser cooling water for vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102. Each system consists of a valved piping loop, a pair of redundant recirculation pumps, a closed-loop evaporative cooling tower, and supporting instrumentation; equipment is located outside the farm on concrete slabs. Piping is routed to the each ventilation condenser inside the farm via below-grade concrete trenches. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

Clifton, F.T.

1997-11-04

24

Effects of water exchange regimes on growth, survival and shell normality of the hatchery reared juvenile spotted babylon ( Babylonia areolata Link 1807) in a recirculating seawater system  

Microsoft Academic Search

Growth, survival and shell normality of hatchery reared juvenile Babylonia areolata were examined at four water exchange regimes of 0, 15, 30 and 60 day intervals in a recirculating seawater system over a 120 day experimental period. Higher body weight gains and shell length increments were observed in snails held at water exchange of 15 day intervals, especially when compared with those

S. Kritsanapuntu; N. Chaitanawisuti; W. Santhaweesuk; S. Y. Natsukari

2006-01-01

25

Effects of elevated atmospheric carbon dioxide concentrations on water and acid requirements of soybeans grown in a recirculating hydroponic system  

NASA Technical Reports Server (NTRS)

Establishing mass budgets of various crop needs, i.e. water and nutrients, in different environments is essential for the Controlled Ecological Life Support System (CELSS). The effects of CO2 (500 and 1000 umol mol (exp -1)) on water and acid use (for pH control) by soybeans in a recirculating hydroponic system were examined. Plants of cvs. McCall and Pixie were grown for 90 days using the nutrient film technique (NFT) and a nitrate based nutrient solution. System acid use for both CO2 levels peaked near 4 weeks during a phase of rapid vegetative growth, but acid use decreased more rapidly under 500 compared to 1000 umol mol (exp GR) CO2. Total system water use by 500 and 1000 umol mol (exp -1) plants was similar, leaving off at 5 weeks and declining as plants senesced (ca. 9 weeks). However, single leaf transpiration rates were consistently lower at 1000 umol mol (exp -1). The data suggest that high CO2 concentrations increase system acid (and nutrient) use because of increased vegetative growth, which in turn negates the benefit of reduced water use (lower transpiration rates) per unit leaf area.

Mackowiak, C. L.; Wheeler, R. M.; Lowery, W.; Sager, J. C.

1990-01-01

26

In-tank recirculating arsenic treatment system  

DOEpatents

A low-cost, water treatment system and method for reducing arsenic contamination in small community water storage tanks. Arsenic is removed by using a submersible pump, sitting at the bottom of the tank, which continuously recirculates (at a low flow rate) arsenic-contaminated water through an attached and enclosed filter bed containing arsenic-sorbing media. The pump and treatment column can be either placed inside the tank (In-Tank) by manually-lowering through an access hole, or attached to the outside of the tank (Out-of-Tank), for easy replacement of the sorption media.

Brady, Patrick V. (Albuquerque, NM); Dwyer, Brian P. (Albuquerque, NM); Krumhansl, James L. (Albuquerque, NM); Chwirka, Joseph D. (Tijeras, NM)

2009-04-07

27

Effect of copper on the growth of shrimps Litopenaeus vannamei: water parameters and copper budget in a recirculating system  

NASA Astrophysics Data System (ADS)

Shrimps (Litopenaeus vannamei) were intensively cultured in a recirculating aquaculture system for 98 days to investigate effects of 0.3 mg/L Cu on its performance, Cu budget, and Cu distribution. Shrimps in Cu-treated systems had greater mean final weight (11.10 vs 10.50 g), body length (107.23 vs 106.42 mm), survival rate (67.80% vs 66.40%), and yield (6.42 vs 5.99 kg/m3), and lower feed conversion ratio (1.20 vs 1.29) than those in control systems but the differences were not significant. Vibrio numbers remained stable (104-106 colony forming units/mL) in the rearing tanks of both control and treated systems. Total ammonium-N, nitrite-N, nitrate-N, pH, chemical oxygen demand, 5-day carbonaceous biochemical oxygen demand, and total suspended solids were similar in controls and treatments. Dissolved Cu concentration in the treated systems decreased from 0.284 to 0.089 mg/L while in the control systems it increased from 0.006 2 to 0.018 mg/L. The main sources of Cu in the treated systems were the artificially added component (75.7% of total input), shrimp feed (21.0%), water (2.06%), and shrimp biomass (1.22%). The major outputs of Cu occurred via the mechanical filter (41.7%), water renewal (15.6%), and draining of the sediment trap (15.1%). The foam fractionator removed only 0.69% of total Cu input. Harvested shrimp biomass accounted for 11.68% of Cu input. The Cu concentration of shrimps in the Cu-treated systems (30.70 mg/kg wet weight) was significantly higher than that in control systems (22.02 mg/kg). Both were below the maximum permissible concentration (50 mg/kg) for Cu in seafood for human consumption in China. Therefore, recirculating systems can be used for commercial on-growing of Litopenaeus vannamei without loss of shrimp quality, even in water polluted by 0.30 mg/L Cu. The mechanical filter is the main route for Cu removal.

Cheng, Bo; Liu, Ying; Yang, Hongsheng; Song, Yi; Li, Xian

2014-05-01

28

Future of recirculating systems in the US aquaculture industry  

SciTech Connect

Recirculating systems consist of a culture unit, a recirculating pump, and a treatment block which facilitate extended re-use of water in the rearing of aquatic animals. As water re-use is extended from a few hours to months or even years, the complexity of the treatment block increases. Classified as either `open` with greater than 10 percent water replacement per day or `closed` with less than 10 percent daily replacement, most recirculating systems include aerators, clarifiers, and biofilters as key core elements. The aquaculture industry is increasingly facing a variety of socio-economic issues which will dramatically influence its future development. These problems range from increased competition for water rights through price depression and foreign imports to predation by protected migratory birds. As water-use, environmental, and conservation conflicts grow, the cost differences between the flow-through and closed production technologies will narrow, increasing the industry`s use of recirculating systems.

Malone, R.F.

1994-08-01

29

Turbocharged engine exhaust gas recirculation system  

Microsoft Academic Search

Improved exhaust gas recirculation systems for turbocharged gas engines that include an exhaust pipe, a turbocharger connected thereto, and a carburetor connected with a source of gas for the engine. The recirculation system includes an air conduit extending from the turbocharger compressor discharge to a venturi, an exhaust gas conduit that extends from a connection with the exhaust pipe between

Stachowicz

1984-01-01

30

Measurement of in-core and recirculation system response to hydrogen water chemistry at Nine Mile Point 1  

SciTech Connect

The value of hydrogen water chemistry (HWC) as a mitigation technique for out-of-core piping systems susceptible to intergranular stress corrosion cracking (IGSCC) is well established. However, certain reactor internal components exposed to high levels of radiation are susceptible to a cracking mechanism referred to as irradiation assisted stress corrosion cracking (IASCC). Some of the components potentially affected by IASCC include the top guide, SRM/IRM housings, the core shroud, and control blades. Fortunately, laboratory data indicate that IASCC can be controlled by altering the coolant environment. Hot cell tests performed at GE's Vallecitos Nuclear Center (VNC) on highly irradiated material produced a fracture surface with 99% IGSCC under normal BWR water chemistry. However, under HWC conditions, only ductile failure occurred. With this background, a program was established to determine the chemistry and oxidizing potential of the core bypass coolant at Nine Mile Point-1 (NMP-1) under normal and HWC conditions. The objective of the program was to assess whether HWC could sufficiently modify the core bypass environment to mitigate IASCC. Results showed that with the addition of hydrogen to the feedwater, core bypass dissolved oxygen decreased very rapidly, compared to the recirculation water, indicating very efficient recombination of hydrogen and oxygen in the non-boiling core bypass region. Since low concentrations of dissolved oxygen have been shown to eliminate IASCC, these results are encouraging. 8 figs., 1 tab.

Head, R.A.; Indig, M.E.; Andresen, P.L. (General Electric Co., San Jose, CA (USA). Nuclear Energy Business Operations)

1991-03-01

31

Water and Energy Savings using Demand Hot Water Recirculating Systems in Residential Homes: A Case Study of Five Homes in Palo Alto, California  

SciTech Connect

This report summarizes a preliminary study aimed at estimating the potential of saving potable water, (and the electrical energy used to heat it), that is presently lost directly to the drain while occupants wait for hot water to arrive at the faucet (point of use). Data were collected from five single-family homes in Palo Alto, California. Despite the small sample size in this study, the results make a compelling case for retrofitting homes with hot water recirculation systems to eliminate unnecessary wastage of water at the point of use. Technical as well as behavioral and attitudinal changes towards water conservation are necessary for a fulfilling and successful conservation effort. This report focuses on the technical issues, but behavioral issues are also noted, which may be factored into future studies involving local and state governments and utility companies.

Ally, M.R.

2002-11-14

32

Hexachlorobenzene Uptake by Fathead Minnows and Macroinvertebrates in Recirculating Sediment/Water Systems.  

National Technical Information Service (NTIS)

Fathead minnow (Pimephales promelas), the worm, Lumbriculus variegatus, and the amphipods Hyalella azteca and Gammarus lacustris were exposed to hexachlorobenzene (HCB) in water with and without a bed of HCB-spiked sediment. Water HCB concentrations were ...

G. S. Schuytema D. F. Krawczyk W. L. Griffis A. V. Nebeker M. L. Robideaux

1990-01-01

33

HEXACHLOROBENZENE UPTAKE BY FATHEAD MINNOWS AND MACRO INVERTEBRATES IN RECIRCULATING SEDIMENT/WATER SYSTEMS  

EPA Science Inventory

Fathead minnow (Pimephales promelas), the worm, Lumbriculus variegatus, and the amphipods Hyalella azteca and Gammarus lacustris were exposed to hexachlorobenzene (HCB) in water with and without a bed of HCB-spiked sediment. ater HCB concentrations were maintained by recirculatio...

34

Nitrite-oxidizing bacteria, Nitrospira, distribution in the outer layer of the biofilm from filter materials of a recirculating water system for the goldfish Carassius auratus  

Microsoft Academic Search

We used a clone library method to investigate changes in the biofilm microflora associated with the conditioning of filter materials in a recirculating water system for the culture of goldfish Carassius auratus. The microbial density was higher in the outer layer of biofilm from filter materials (1.7×1010–3.0×1010 cells\\/g) than in the inner layer (1.5×109–2.4×109 cells\\/g) throughout the experimental period. The clone library

Shiro Itoi; Noriaki Ebihara; Sayaka Washio; Haruo Sugita

2007-01-01

35

Effect of CaCO? particles and suspended bacteria on biofilm components and activity in the model recirculating cooling water system.  

PubMed

Biofilms are a serious problem in industrial recirculating cooling water systems. Biofilm formation and properties are affected by many factors, such as inorganic particles and suspended bacteria. In this research a laboratory model recirculating cooling water system was applied to investigate the effects of CaCO(3) concentration and suspended bacterial count on extracellular polymeric substances (EPS) content and dehydrogenase activity (DHA) in the attached biofilms. In addition, nutrient level was also the key factor when investigating the effect of suspended bacterial count. The results showed that EPS content and DHA first increased and then decreased with the increase of CaCO(3) concentration from 0 to 200 mg/l. At the low nutrient level, with the increase of suspended bacterial count from 4.04 to 5.78 log(10) c.f.u./ml, biofilm EPS content decreased firstly and then increased. However, biofilm DHA always gradually increased. At the medium nutrient level, biofilm EPS content increased firstly and then decreased and DHA always gradually decreased when suspended bacterial count ranged from 4.04 to 5.78 log(10) c.f.u./ml. At the high nutrient level, biofilm EPS content and DHA both showed the increasing trend with the increase of suspended bacterial count. This work provides the basis and reference for management strategies in actual recirculating cooling water systems. PMID:22805808

Liu, Fang; Dong, Wenwen; Yang, Fei; Lu, Lei; Wang, Yongqiang; Yin, Xiaochen; Zhao, Chaocheng

2012-03-01

36

Silica scale technology and water conservation. [Recirculating evaporative cooling  

Microsoft Academic Search

Conservation of water at the Los Alamos Scientific Laboratory (LASL) has been accomplished by recirculating evaporative cooling waters. Because of high silica concentration (80 mg\\/l) in Los Alamos groundwater, the concentration of recirculating water must be carefully controlled to prevent scaling. The most troublesome scale at Los Alamos has been identified as colloidal silica bound in a crystalline matrix of

W. S. Midkiff; H. P. Foyt

1976-01-01

37

Hydrothermal carbonization: process water characterization and effects of water recirculation.  

PubMed

Poplar wood chips were treated hydrothermally and the increase of process efficiency by water recirculation was examined. About 15% of the carbon in the biomass was dissolved in the liquid phase when biomass was treated in de-ionized water at 220 °C for 4 h. The dissolved organic matter contained oxygen and was partly aerobically biodegradable. About 30-50% of the total organic carbon originated from organic acids. A polar and aromatic fraction was extracted and a major portion of the organic load was of higher molecular weight. By process water recirculation organic acids in the liquid phase concentrated and catalyzed dehydration reactions. As a consequence, functional groups in hydrothermally synthesized coal declined and dewaterability was enhanced. Recirculated reactive substances polymerized and formed additional solid substance. As a result, carbon and energetic yields of the produced coal rose to 84% and 82%, respectively. PMID:23792664

Stemann, Jan; Putschew, Anke; Ziegler, Felix

2013-09-01

38

Exhaust gas recirculation system for diesel engine  

SciTech Connect

An exhaust gas recirculation control system calculates a target EGR ratio value based upon engine operating parameters and maintains the EGR ratio at the target EGR ratio value. Each time the vehicle travels a predetermined distance, the control system calculates an actual EGR ratio value and corrects the target EGR ratio value to reduce a deviation between the target and actual EGR ratio values to zero.

Masaki, K.; Yasuhara, S.

1984-02-28

39

Re-circulating linac vacuum system  

SciTech Connect

The vacuum system for a proposed 2.5 GeV, 10{Mu}A recirculating linac synchrotron light source [1] is readily achievable with conventional vacuum hardware and established fabrication processes. Some of the difficult technical challenges associated with synchrotron light source storage rings are sidestepped by the relatively low beam current and short beam lifetime requirements of a re-circulating linac. This minimal lifetime requirement leads directly to relatively high limits on the background gas pressure through much of the facility. The 10{Mu}A average beam current produces very little synchrotron radiation induced gas desorption and thus the need for an ante-chamber in the vacuum chamber is eliminated. In the arc bend magnets, and the insertion devices, the vacuum chamber dimensions can be selected to balance the coherent synchrotron radiation and resistive wall wakefield effects, while maintaining the modest limits on the gas pressure and minimal outgassing.

Wells, Russell P.; Corlett, John N.; Zholents, Alexander A.

2003-05-09

40

Ozonation followed by ultraviolet irradiation provides effective bacteria inactivation in a freshwater recirculating system  

Microsoft Academic Search

Recirculating aquaculture systems may require an internal disinfection process to control population growth of pathogens and heterotrophic bacteria. Ozonation and ultraviolet (UV) irradiation are two technologies that have been used to treat relatively large aquaculture flows, including flows within freshwater systems that recirculate water. The objective of the present study was to evaluate the effectiveness of ozone application alone or

Mark J. Sharrer; Steven T. Summerfelt

2007-01-01

41

Molecular adsorbent and re-circulating system.  

PubMed

The molecular adsorbent recirculating system (MARS) is a non-biological artificial liver support system. Used for almost a decade, there are only two randomized controlled trials on the efficacy of MARS till date. A number of uncontrolled studies have documented a marked improvement in the biochemical parameters of patients after MARS. Although MARS seems to be an effective and promising tool in the management of liver failure, its cost needs to be reduced to enable it use in a member of indications. PMID:15471317

Batra, Yogesh; Dutta, Amit Kumar; Dutta, Amitabh; Acharya, Subrat Kumar

2004-01-01

42

Use of Treated Municipal Wastewater as Power Plant Cooling System Makeup Water: Tertiary Treatment versus Expanded Chemical Regimen for Recirculating Water Quality Management  

SciTech Connect

Treated municipal wastewater is a common, widely available alternative source of cooling water for thermoelectric power plants across the U.S. However, the biodegradable organic matter, ammonia-nitrogen, carbonate and phosphates in the treated wastewater pose challenges with respect to enhanced biofouling, corrosion, and scaling, respectively. The overall objective of this study was to evaluate the benefits and life cycle costs of implementing tertiary treatment of secondary treated municipal wastewater prior to use in recirculating cooling systems. The study comprised bench- and pilot-scale experimental studies with three different tertiary treated municipal wastewaters, and life cycle costing and environmental analyses of various tertiary treatment schemes. Sustainability factors and metrics for reuse of treated wastewater in power plant cooling systems were also evaluated. The three tertiary treated wastewaters studied were: secondary treated municipal wastewater subjected to acid addition for pH control (MWW_pH); secondary treated municipal wastewater subjected to nitrification and sand filtration (MWW_NF); and secondary treated municipal wastewater subjected nitrification, sand filtration, and GAC adsorption (MWW_NFG). Tertiary treatment was determined to be essential to achieve appropriate corrosion, scaling, and biofouling control for use of secondary treated municipal wastewater in power plant cooling systems. The ability to control scaling, in particular, was found to be significantly enhanced with tertiary treated wastewater compared to secondary treated wastewater. MWW_pH treated water (adjustment to pH 7.8) was effective in reducing scale formation, but increased corrosion and the amount of biocide required to achieve appropriate biofouling control. Corrosion could be adequately controlled with tolytriazole addition (4-5 ppm TTA), however, which was the case for all of the tertiary treated waters. For MWW_NF treated water, the removal of ammonia by nitrification helped to reduce the corrosivity and biocide demand. Also, the lower pH and alkalinity resulting from nitrification reduced the scaling to an acceptable level, without the addition of anti-scalant chemicals. Additional GAC adsorption treatment, MWW_NFG, yielded no net benefit. Removal of organic matter resulted in pitting corrosion in copper and cupronickel alloys. Negligible improvement was observed in scaling control and biofouling control. For all of the tertiary treatments, biofouling control was achievable, and most effectively with pre-formed monochloramine (2-3 ppm) in comparison with NaOCl and ClO2. Life cycle cost (LCC) analyses were performed for the tertiary treatment systems studied experimentally and for several other treatment options. A public domain conceptual costing tool (LC3 model) was developed for this purpose. MWW_SF (lime softening and sand filtration) and MWW_NF were the most cost-effective treatment options among the tertiary treatment alternatives considered because of the higher effluent quality with moderate infrastructure costs and the relatively low doses of conditioning chemicals required. Life cycle inventory (LCI) analysis along with integration of external costs of emissions with direct costs was performed to evaluate relative emissions to the environment and external costs associated with construction and operation of tertiary treatment alternatives. Integrated LCI and LCC analysis indicated that three-tiered treatment alternatives such as MWW_NSF and MWW_NFG, with regular chemical addition for treatment and conditioning and/or regeneration, tend to increase the impact costs and in turn the overall costs of tertiary treatment. River water supply and MWW_F alternatives with a single step of tertiary treatment were associated with lower impact costs, but the contribution of impact costs to overall annual costs was higher than all other treatment alternatives. MWW_NF and MWW_SF alternatives exhibited moderate external impact costs with moderate infrastructure and chemical conditioner dosing, which makes them (especially

David Dzombak; Radisav Vidic; Amy Landis

2012-06-30

43

Effect of oxidizing and non-oxidizing biocides on biofilm at different substrate levels in the model recirculating cooling water system  

Microsoft Academic Search

With the reducing of water resources, using advanced treated refinery wastewater as recirculating cooling water is an effective\\u000a method to save water and to reduce the pollution of petroleum and petrochemical industry. However, the control of biofilm\\u000a is a bottleneck in the application of this technology. To resolve the problem of biofilm formation and development, antimicrobial\\u000a characteristics of chlorine dioxide

Fang Liu; Xin Chang; Fei Yang; Yongqiang Wang; Feiyang Wang; Wenwen Dong; Chaocheng Zhao

44

Exhaust gas recirculation system for an internal combustion engine  

DOEpatents

An exhaust gas recirculation system for an internal combustion engine comprises an exhaust driven turbocharger having a low pressure turbine outlet in fluid communication with an exhaust gas conduit. The turbocharger also includes a low pressure compressor intake and a high pressure compressor outlet in communication with an intake air conduit. An exhaust gas recirculation conduit fluidly communicates with the exhaust gas conduit to divert a portion of exhaust gas to a low pressure exhaust gas recirculation branch extending between the exhaust gas recirculation conduit and an engine intake system for delivery of exhaust gas thereto. A high pressure exhaust gas recirculation branch extends between the exhaust gas recirculation conduit and the compressor intake and delivers exhaust gas to the compressor for mixing with a compressed intake charge for delivery to the intake system.

Wu, Ko-Jen

2013-05-21

45

Internal combustion engine having exhaust gas recirculation system  

Microsoft Academic Search

An internal combustion engine has an exhaust gas recirculation system including a recirculation valve for controlling the amount of exhaust gas returned to the intake system. The position or opening of the valve is controlled to a desired position in accordance with a memory in a memory device storing desired valve positions under various combinations of the engine load and

K. Iida; K. Okazaki; Y. Yada

1983-01-01

46

Water recirculation and good management: potential methods to avoid disease outbreaks with Flavobacterium psychrophilum.  

PubMed

Flavobacterium psychrophilum infections cause high mortality among rainbow trout, Oncorhynchus mykiss, fry in Danish fish farms and hatcheries. Hatcheries based entirely on bore-hole water recirculation systems have been suggested as a possibility for eliminating F. psychrophilum or at least keeping the amount of this bacterium low. The occurrence of the bacterium in a bore-hole water recirculation system was compared with a combined bore-hole water and stream water flow-through system in a hatchery where outbreaks of rainbow trout fry syndrome caused by F. psychrophilum often occurred. Broodfish, unfertilized and fertilized eggs, eyed eggs and fry, as well as water samples from the tanks/troughs with broodfish/fry, were examined. Suspect yellow bacterial colonies were either confirmed or rejected as F. psychrophilum by growth characteristics and by PCR. As both virulent and less virulent F. psychrophilum isolates are known, isolates were characterized. The isolates were ribotyped and grouped according to ribotyping patterns. Representatives of the groups were serotyped. Fry isolates were very homogeneous whereas isolates from broodfish were heterogeneous, whether the isolates originated from external surfaces of the fish (mucus from skin and gills, haemorrhages and ulcers) or internal organs. Flavobacterium psychrophilum was isolated from broodfish in both water systems; 56% of investigated broodfish from the borehole/flowthrough system and 36% from the recirculation facility harboured the bacterium. In the recirculation system, the bacterium was isolated from fish (ulcers, milt, liver, abdominal cavity) kept in the system for 11 months. Flavobacterium psychrophilum was found in milt and ovarian fluid as well as on the surface of fertilized eggs, but not inside the eggs. Fry also harboured F. psychrophilum, but in the water recirculation system the bacterium was first isolated from the fry after they had been graded. Flavobacterium psychrophilum was found regularly in other parts of the hatchery (outside the recirculation facility), including at the time of grading, suggesting that the occurrence of F. psychrophilum in the fry recirculation facility was due to contamination from the borehole/flow-through hatchery. It is suggested that the combination of bore-hole water recirculation systems and good management procedures (including egg disinfection) is a possible method for hatcheries to avoid disease outbreaks due to F. psychrophilum. PMID:19238756

Madsen, L; Dalsgaard, I

2008-11-01

47

Konoritsu gyorui seisan no tame no suishitsu joka gijutsu no kaihatsu. 10. Hirame shiiku eno koteika biseibutsu no tekiyo. (Development of water purification technologies for intensive fish culture. 10. Rearing of Japanese flounder with closed seawater recirculation system equipped with immobilized bacteria).  

National Technical Information Service (NTIS)

Japanese flounder were reared by a seawater recirculation and filtration system with immobilized bacteria. As a water purification system, used were a nitrification tank and denitrification tank which were both filled with immobilized nitrifying bacteria ...

H. Uemoto Y. Watanabe K. Kikuchi

1994-01-01

48

Continuous hydroponic wheat production using a recirculating system  

NASA Technical Reports Server (NTRS)

Continuous crop production, where plants of various ages are growing simultaneously in a single recirculating nutrient solution, is a possible alternative to batch production in a Controlled Ecological Life Support System. A study was conducted at John F. Kennedy Space Center where 8 trays (0.24 sq m per tray) of Triticum aestivum L. Yecora Rojo were grown simultaneously in a growth chamber at 23 C, 65 percent relative humidity, 1000 ppm CO2, continuous light, with a continuous flow, thin film nutrient delivery system. The same modified Hoagland nutrient solution was recirculated through the plant trays from an 80 L reservoir throughout the study. It was maintained by periodic addition of water and nutrients based on chemical analyses of the solution. The study was conducted for 216 days, during which 24 trays of wheat were consecutively planted (one every 9 days), 16 of which were grown to maturity and harvested. The remaining 8 trays were harvested on day 216. Grain yields averaged 520 g m(exp -2), and had an average edible biomass of 32 percent. Consecutive yields were unaffected by nutrient solution age. It was concluded that continual wheat production will work in this system over an extended period of time. Certain micronutrient deficiencies and toxicities posed problems and must be addressed in future continuous production systems.

Mackowiak, C. L.; Owens, L. P.; Hinkle, C. R.; Prince, R. P.

1989-01-01

49

Nutrient removal from aquaculture wastewater by vegetable production in aquaponics recirculation system  

Microsoft Academic Search

Nutrient removal is essential for aquaculture wastewater treatment to protect receiving water from eutrophication and for potential reuse of the treated water. The integration of aquaculture with agriculture appears to be an excellent way of saving water, disposing aquaculture wastewater and providing fertilizer to the agricultural crop. The study was conducted to evaluate aquaponics recirculation system (ARS) performance in removing

A. Enduta; A. Jusoh; N. Ali; W. B. Wan Nik

2011-01-01

50

Microparticles in recirculating aquaculture systems: microscopic examination of particles  

Microsoft Academic Search

In order to determine the composition, shape and structure of micro-particles in a cold water recirculating plant raising juvenile Atlantic salmon to the smolt stage, samples of suspended solids, collected on classification meshes, and samples of particles in the culture water were examined microscopically. Concurrent gravimetric tests were attempted which method proved unusable due to clogging of the meshes by

R. N. Patterson; K. C. Watts

2003-01-01

51

Performance of a Water Recirculation Loop Maintenance Device and Process for the Advanced Spacesuit Water Membrane Evaporator  

NASA Technical Reports Server (NTRS)

A water loop maintenance device and process to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop has been undergoing a performance evaluation. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the water recirculation maintenance device and process is to further enhance this advantage through the leveraging of fluid loop management lessons-learned from the International Space Station (ISS). A bed design that was developed for a Hamilton Sundstrand military application, and considered for a potential ISS application with the Urine Processor Assembly, provides a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The maintenance process further leverages a sorbent developed for ISS that introduces a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware. This

Rector, Tony; Steele, John W.; Bue, Grant C.; Campbell, Colin; Makinen, Janice

2012-01-01

52

Performance of a Water Recirculation Loop Maintenance Device and Process for the Advanced Spacesuit Water Membrane Evaporator  

NASA Technical Reports Server (NTRS)

A dual-bed device to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop has been designed and is undergoing testing. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the development of a water recirculation maintenance device is to further enhance this advantage through the leveraging of fluid loop management lessons-learned from the International Space Station (ISS). A bed design that was developed for a Hamilton Sundstrand military application, and considered for a potential ISS application with the Urine Processor Assembly, provides a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The bed design further leverages a sorbent developed for ISS that introduces a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware.

Steele, John W.; Rector, Tony; Bue, Grant C.; Campbell, Colin; Makinen, Janice

2013-01-01

53

Design and Evaluation of a Water Recirculation Loop Maintenance Device for the Advanced Spacesuit Water Membrane Evaporator  

NASA Technical Reports Server (NTRS)

A dual-bed device to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop has been designed and is undergoing testing. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing sublimator technology. The driver for the development of a water recirculation maintenance device is to further enhance this advantage through the leveraging of fluid loop management lessons learned from the International Space Station (ISS). A bed design that was developed for a Hamilton Sundstrand military application, and considered for a potential ISS application with the Urine Processor Assembly, provides a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high-capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit Transport Water Loop. The bed design further leverages a sorbent developed for the ISS that introduces a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System. The leveraging of these water maintenance technologies to the SWME recirculation loop is a unique demonstration of applying the valuable lessons learned on the ISS to the next generation of crewed spaceflight Environmental Control and Life Support System hardware.

Steele, John W.; Rector, Tony; Bue, Grant C.; Campbell, Colin; Makinen, Janice

2012-01-01

54

Design and Evaluation of a Water Recirculation Loop Maintenance Device for the Advanced Spacesuit Water Membrane Evaporator  

NASA Technical Reports Server (NTRS)

A dual-bed device to maintain the water quality of the Advanced Spacesuit Water Membrane Evaporation (SWME) water recirculation loop has been designed and is undergoing testing. The SWME is a heat rejection device under development at the NASA Johnson Space Center to perform thermal control for advanced spacesuits. One advantage to this technology is the potential for a significantly greater degree of tolerance to contamination when compared to the existing Sublimator technology. The driver for the development of a water recirculation maintenance device is to further enhance this advantage through the leveraging of fluid loop management lessons-learned from the International Space Station (ISS). A bed design that was developed for a Hamilton Sundstrand military application, and considered for a potential ISS application with the Urine Processor Assembly, provides a low pressure drop means for water maintenance in a recirculation loop. The bed design is coupled with high capacity ion exchange resins, organic adsorbents, and a cyclic methodology developed for the Extravehicular Mobility Unit (EMU) Transport Water loop. The bed design further leverages a sorbent developed for ISS that introduces a biocide in a microgravity-compatible manner for the Internal Active Thermal Control System (IATCS). The leveraging of these water maintenance technologies to the SWME recirculation loop is a clear demonstration of applying the valuable lessons learned on the ISS to the next generation of manned spaceflight Environmental Control and Life Support System (ECLSS) hardware.

Steele, John W.; Rector, Tony; Bue, Grant C.; Campbell, Colin; Makinen, Janice

2011-01-01

55

Fast response exhaust gas recirculation (EGR) system  

SciTech Connect

This patent describes an exhaust gas recirculation (EGR) control for an automotive type internal combustion engine. It comprises: a gas induction passage connected to the engine intake manifold at one end, an EGR passage connected at one end to exhaust gases from the engine combustion chamber, the other end of the induction passage being bifurcated to form ambient air and EGR branch passages, means connecting the ambient air branch passage to ambient air, means connecting the EGR branch passage to the other end of the EGR passage whereby ambient air and EGR gases combine to form a gas charge inducted into the engine.

Wade, W.R.

1990-05-15

56

A study on the optimal hydraulic loading rate and plant ratios in recirculation aquaponic system  

Microsoft Academic Search

The growths of the African catfish (Clarias gariepinus) and water spinach (Ipomoea aquatica) were evaluated in recirculation aquaponic system (RAS). Fish production performance, plant growth and nutrient removal were measured and their dependence on hydraulic loading rate (HLR) was assessed. Fish production did not differ significantly between hydraulic loading rates. In contrast to the fish production, the water spinach yield

Azizah Endut; A. Jusoh; N. Ali; W. B. Wan Nik; A. Hassan

2010-01-01

57

Recirculating Molten Metal Supply System And Method  

DOEpatents

The melter furnace includes a heating chamber (16), a pump chamber (18), a degassing chamber (20), and a filter chamber (22). The pump chamber (18) is located adjacent the heating chamber (16) and houses a molten metal pump (30). The degassing chamber (20) is located adjacent and in fluid communication with the pump chamber (18), and houses a degassing mechanism (36). The filter chamber (22) is located adjacent and in fluid communication with the degassing chamber (20). The filter chamber (22) includes a molten metal filter (38). The melter furnace (12) is used to supply molten metal to an externally located holder furnace (14), which then recirculates molten metal back to the melter furnace (12).

Kinosz, Michael J. (Apollo, PA); Meyer, Thomas N. (Murrysville, PA)

2003-07-01

58

Closed recirculating system for shrimp-mollusk polyculture  

NASA Astrophysics Data System (ADS)

This paper deals with a new system of aquaculture, i.e., a closed recirculating system for shrimp-mollusk polyculture. The culture system consisted of several shrimp ponds, a mollusk water-purifying pond and a reservoir. During the production cycle, water circulated between the shrimp and mollusk ponds, and the reservoir compensated for water loss from seepage and evaporation. Constricted tagelus, Sinonovacula constricta, was selected as the cultured mollusk, and Pacific white shrimp, Litopenaeus vannamei, as the cultured shrimp. The main managing measures during the production cycle were: setting and using the aerators; introducting the probiotic products timely into the shrimp ponds; adopting a “pen-closing” method for controlling shrimp viral epidemics; setting the flow diversion barriers in the mollusk pond to keep the circulating water flowing through the pond along a sine-like curve and serve as substrate for biofilm; no direct feeding was necessary for the cultured mollusk until the co-cultured shrimp was harvested; natural foods in the water from the shrimp ponds was used for their foods. Two sets of the system were used in the experiment in 2002 and satisfactory results were achieved. The average yield of the shrimp was 11 943.5 kg/hm2, and that of the mollusk was 16 965 kg/hm2. After converting the mollusk yield into shrimp yield at their market price ratio, the food coefficient of the entire system averaged at as low as 0.81. The water quality in the ponds was maintained at a desirable level and no viral epidemics were discovered during the production cycle.

Wu, Xiongfei; Zhao, Zhidong; Li, Deshang; Chang, Kangmei; Tong, Zhuanshang; Si, Liegang; Xu, Kaichong; Ge, Bailin

2005-12-01

59

Growth and survival of juvenile cobia, Rachycentron canadum, at different salinities in a recirculating aquaculture system  

Microsoft Academic Search

Cobia (Rachycentron canadum) is an emerging aquaculture candidate for both offshore cage culture and land-based systems such as recirculating aquaculture systems. The ability to grow cobia at salinities other than oceanic (?34 ppt) could present culturists with additional production opportunities with this species. Culture at low salinities could also reduce the incidence of disease and simplify water management. In two

Matthew J. Resley; Kenneth A. Webb; G. Joan Holt

2006-01-01

60

An Inexpensive Recirculating Aquaculture System with Multiple Use Capabilities.  

ERIC Educational Resources Information Center

Describes the construction of an inexpensive recirculating aquaculture system that can hold up to 46 pounds of fish, invertebrates, and mussels for classroom use. The system is versatile, requires little maintenance, and can be used for both teaching and research purposes. (WRM)

Scurlock, Gerald Don, Jr.; Cook, S. Bradford; Scurlock, Carrie Ann

1999-01-01

61

Design of a computerized, temperature-controlled, recirculating aquaria system  

USGS Publications Warehouse

We built a recirculating aquaria system with computerized temperature control to maintain static temperatures, increase temperatures 1 ??C/day, and maintain diel temperature fluctuations up to 10 ??C. A LabVIEW program compared the temperature recorded by thermocouples in fish tanks to a desired set temperature and then calculated the amount of hot or cold water to add to tanks to reach or maintain the desired temperature. Intellifaucet?? three-way mixing valves controlled temperature of the input water and ensured that all fish tanks had the same turnover rate. The system was analyzed over a period of 50 days and was fully functional for 96% of that time. Six different temperature treatments were run simultaneously in 18, 72 L fish tanks and temperatures stayed within 0.5 ??C of set temperature. We used the system to determine the upper temperature tolerance of fishes, but it could be used in aquaculture, ecological studies, or other aquatic work where temperature control is required. ?? 2005 Elsevier B.V. All rights reserved.

Widmer, A. M.; Carveth, C. J.; Keffler, J. W.; Bonar, S. A.

2006-01-01

62

Exhaust gas recirculation system for an internal combustion engine  

Microsoft Academic Search

In an internal combustion engine having an intake passage provided therein with a throttle valve for controlling intake flow of air or an air-fuel mixture passing therethrough toward engine cylinders and an exhaust passage, an exhaust gas recirculation system comprises first means for conducting a portion of the exhaust gases from the exhaust passage into the intake passage downstream of

Higashi

1984-01-01

63

Microbial corrosion of galvanized steel in a simulated recirculating cooling tower system  

Microsoft Academic Search

In this study, mixed species biofilm formation including sulphate reducing bacteria (SRB) on the galvanized steel surfaces and also microbiologically influenced corrosion (MIC) of galvanized steel were observed in a model recirculating cooling water system during 10months. A biofilm which had a heterogeneous structure formed on galvanized steel coupons. The results suggested that galvanized steel was corroded by microorganisms as

Esra Ilhan-Sungur; Ay??n Çotuk

2010-01-01

64

The use of ozone in a high density recirculation system for rotifers  

Microsoft Academic Search

The use of ozone in the effluent treatment of a closed recirculation system for rotifers resulted in a significant improvement of rotifer production and water quality. Compared to a control treatment, the rotifer culture exposed to ozone did not only support a higher rotifer biomass (16000 vs. 8000 rotifers ml?1), it also allowed a prolongation of the culture period for

G Suantika; P Dhert; G Rombaut; J Vandenberghe; T De Wolf; P Sorgeloos

2001-01-01

65

Use Of Produced Water In Recirculating Cooling Systems at Power Generating Facilities. Deliverable Number 1: Produced Water Assessment. Semi-Annual Technical Progress Report.  

National Technical Information Service (NTIS)

The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, t...

K. Zammit

2004-01-01

66

Ozonation of a recirculating rainbow trout culture system I. Effects on bacterial gill disease and heterotrophic bacteria  

Microsoft Academic Search

Ozone was added to water in a recirculating rainbow trout (Oncorhynchus mykiss) culture system just before it entered the culture tanks in an attempt to reduce the numbers of heterotrophic bacteria in system water and on trout gills, and to prevent bacterial gill disease (BGD) in newly stocked fingerlings. During four 8-week trials, ozone was added to the system at

Graham L. Bullock; Steven T. Summerfelt; Alicia C. Noble; Amy L. Weber; Martin D. Durant; Joseph A. Hankins

1997-01-01

67

RECIRCULATING - REDUCING AND ALKALINITY PRODUCING SYSTEM (RERAPS) FOR THE TREATMENT OF ACIDIC COAL PILE RUNOFF 1  

Microsoft Academic Search

The treatment of acidic coal pile runoff (CPR) using an alternative constructed wetland design was evaluated. This alternative design, which provided improved wetland performance, was based on the partial re-circulation of treated water into a detention basin located immediately upstream from a Reducing and Alkalinity Producing System (RAPS). This modification created a semi-passive RAPS-based system we refer to as a

William E. Garrett; Alfred A. Bartolucci; Robert R. Pitt; Michael E. Vermace

2002-01-01

68

Recyclotron III, a recirculating plasma fusion system  

SciTech Connect

This patent describes a recyclotron nuclear fusion system comprising recyclotrons. Each recyclotron comprises cyclotron means for receiving and accelerating charged particles in spiral and work conservative pathways. An output means forms a beam from particles received from the cyclotron means; (i) the cyclotron means comprising (a) a channel shaped electromagnet having a pair of indented polefaces, oriented along an input axis and defining an input axis and defining an input magnetic well, (b) a pair of elongated linear electrodes centered along the input magnetic well arranged generally parallel to the input axis and having a gap therebetween, (c) tuned oscillator means connected to the electrodes for applying an oscillating electric potential thereto, (ii) the output means comprising (e) inverter means comprising an electromagnet having a polarity opposite that of the channel shaped electromagnet oriented contigously therealong for extracting fully accelerated particles from the cyclotron means, and (f) reinverter means comprising an electromagnet having a polarity the same as that of the channel shaped electromagnet for correcting the flightpath of the extracted particles.

Jarnagin, W.S.

1987-01-27

69

Exhaust recirculation  

Microsoft Academic Search

An exhaust gas recirculation system for the reduction of nitrogen oxide emissions from internal combustion engine exhaust is described that is uncomplicated by moving parts, thus avoiding problems associated with prior-art recirculation systems. The system also results in preheating and improved mixing of the fuel-air mixture in the inlet header. A recycling duct receives the exhaust gases at a restricted

Waitzmann

1974-01-01

70

Exhaust recirculation  

Microsoft Academic Search

An exhaust gas recirculation system for the reduction of nitrogen oxides in automobile exhaust is described that provides for the reduction of recirculation during engine idling without the prior-art complexities of moving parts. The system also achieves preheating and improved mixing and carburetion of the fuel-air mixture in the inlet header. Exhaust gases are recycled by means of a swirl

Sarto

1974-01-01

71

Growth and Culture of Larval and Juvenile Tautogs in a Closed Recirculating-Seawater System  

Microsoft Academic Search

Field-captured and laboratory-held adult tautogs Tautoga onitis were allowed to spawn naturally under laboratory conditions. Embryos were cultured to hatching and raised successfully through the larval stage to 490-d-old posthatch juveniles. A large (8,500-L), closed, recirculating-seawater system, designed with a biological filter containing air diffusers that passed a strong air?water mixture through a high-surface-area substrate, was used to culture the

Dean M. Perry; Renee Mercaldo-Allen; Stacy Burgh

2001-01-01

72

Parameters affecting HS emissions removal and re-circulating water quality in a pilot-scale sequential biological treatment system at a wastewater lift station in Brownsville, Texas, USA.  

PubMed

In this study, a pilot-scale sequential biological treatment system combining a biotrickling filter and biofilter was used to optimize the removal of variable emission H(2)S loadings ranging from 30 to 120 g m(-3) h(-1)at a wastewater lift station in Brownsville, Texas USA. The biotrickling filter recycle water pH remained between 2.0 to 3.0 during the four months of unit operation and the overall removal efficiency for H(2)S was >99%. The biotrickling filter removal efficiency was 70 ± 8%, with an elimination capacity of 10 to 80 g m(-3) h(-1) while the biofilter elimination capacity ranged from 10 to 40 g m(-3) h(-1). The sequential treatment system was operated initially at an Empty Bed Residence Time (EBRT) of 120 s (50 s for the biotrickling filter and 70 s for biofilter) for two months and then at an EBRT of 60 s (25 s for biotrickling filter and 35s for biofilter) for the remainder of the operating period; remarkably, there was only a slight decrease in removal efficiency at 60 s EBRT. In order to qualitatively evaluate the changes in recycle water quality in the system on the performance of the unit in precipitating sulfur species, the equilibrium chemical model, Visual MINTEQ was employed. The model predicted speciation results based on the feed water quality and sulfur loadings, and also forecast some iron-sulfur complexes which have potential to form some complex precipitates. This research demonstrated that low pH re-circulating water quality in the biological treatment of H(2)S was possible without compromising the high removal efficiency, and that an improved understanding of the recycle water chemistry of the trickling unit of a sequential treatment system could be useful in the overall optimization of the process. PMID:22486667

Karre, Anand K; Bairu, Pavan; Jones, Kim D; Paca, Jan

2012-01-01

73

Inactivation of bacteria using ultraviolet irradiation in a recirculating salmonid culture system  

Microsoft Academic Search

The objective of this research was to determine the ultraviolet (UV) irradiation dosages required to inactivate bacteria in a commercial-scale recirculating salmonid culture system. Research was conducted in the commercial-scale recirculating system used for Arctic char growout at the Conservation Fund Freshwater Institute (Shepherdstown, West Virginia). This recirculating system uses a UV channel unit to treat 100% of the 4750L\\/min

Mark J. Sharrer; Steven T. Summerfelt; Graham L. Bullock; Lauren E. Gleason; Jessica Taeuber

2005-01-01

74

Monitoring carbon steel corrosion rates in refinery recirculating water  

Microsoft Academic Search

The development of measuring devices and corrosion probes for the determination of metal corrosion rates are discussed. The UISK-2 unit has been used to evaluate the efficiency of a corrosion inhibitor, sodium silicate, used for the corrosion protection of carbon steel. Satisfactory corrosion protection of carbon steel is given by the addition of 100 mg\\/liter of SiOâ to the recirculating

Yu. G. Kotlov; V. V. Burlov; S. G. Polyakov; B. M. Teslya; A. A. Yurutkin

1985-01-01

75

Development of a Turbulence-Resolving, Three-dimensional, Free Water Surface Numerical Model for Recirculation Eddies in Grand Canyon  

NASA Astrophysics Data System (ADS)

In the Colorado River in Grand Canyon, sand bars, which are built in recirculation areas downstream of channel expansions are valuable resources, particularly as natural habitat for endangered native fish and recreation sites for recreation. Since the closure of Glen Canyon Dam in 1963, there has been a reduction in the size of recirculation eddy bars. Simulated floods in the Colorado after tributary flood sediment input from the Paria River are being investigated as a method of rebuilding recirculation eddy beaches. Time-averaged, two-dimensional (and quasi- three-dimensional) numerical models have been employed to predict deposition during these beach/habit-building test flows. However, behind channel expansion areas, flows are strongly three-dimensional and the cross-channel flow is driven primarily by upwelling boils along the eddy fence that are neither stationary in time or space. Furthermore, these strong vertical motions along the eddy fence preclude use of the hydrostatic assumption. In this study, a non-hydrostatic three-dimensional numerical model is presented in order to calculate flow velocity in channels having rapid channel expansions. This model employs the Large Eddy Simulation (LES) turbulence modeling technique. LES uses spatial filtering to separate flows into gird scale and sub-gird scale rather than time averaging, thus it directly calculates large-scale turbulent motions. Also, this model employs a moving grid system and the Body Fitted Coordinate (BFC) system. These grid and coordinate systems allow the model to calculate time-dependent free water surface levels induced by large-scale turbulent motions. The model_fs calculation results are compared to existing experimental results of an open channel flow expansion in a laboratory flume. The comparison shows that the model succeeds to reproduce several key features of the flow, such as the temporally- and vertically-averaged horizontal recirculation eddy structure, and the time-averaged cross-stream vertical flow structure, which has inward flow (into the recirculation zone) at the surface and outward flow near the bed. The calculated water surface level also seems adequate. Its maximum is at the upstream side of the channel expansion and 3% higher than that of the minimum at the downstream end of the recirculation zone. Calculation results show that horizontal eddies are intermittently produced along the separation line between the recirculation zone and the main channel, and those produced eddies move into the recirculation zone while expanding their size.

Akahori, R.; Schmeeckle, M. W.

2005-12-01

76

The use of high rate algal ponds for the treatment of marine effluent from a recirculating fish rearing system  

Microsoft Academic Search

A high rate algal pond (HRAP) system was used to treat effluent from a recirculating sea water aquaculture system in southern France. Dicentrarchus labrax L. were farmed at a high density, with effluents containing an average of 10 mg L1 dissolved inorganic nitrogen (DIN) and 1.3 mg L1 reactive phosphorus (RP). On a yearly basis, the algal pond removed 59%

P Pagand; J-P Blancheton; J Lemoalle; C Casellas

2000-01-01

77

A simple recirculating flow system for the calibration of polar organic chemical integrative samplers (POCIS): effect of flow rate on different water pollutants.  

PubMed

A calibration system for POCIS was developed and used to calculate the sampling rates of eight analytes belonging to pesticides, non-steroidal anti-inflammatory drugs and perfluorinated compounds: atrazine, propazine, terbutylazine, diclofenac, ibuprofen, ketoprofen, perfluorooctanoic acid and perfluorooctanesulfonate. Experiments with a linear velocity of 2.0, 5.1, 10.2 and 15.3 cm/s were carried out for 96 h using two different analyte concentrations. POCIS extracts were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS), using multiple reaction monitoring to maximize sensitivity. Results highlighted that the calculated sampling rates are rather constant at the considered concentrations and flow rates. Obtained values of sampling rates were then employed to calculate Time-Weighted Average concentration of the analytes in river and drinking waters. PMID:24468338

Di Carro, Marina; Bono, Luca; Magi, Emanuele

2014-03-01

78

Use Of Produced Water In Recirculating Cooling Systems at Power Generating Facilities. Deliverable Number 2: Infrastructure Availability and Transportation Analysis. Semi-Annual Technical Progress Report.  

National Technical Information Service (NTIS)

The purpose of this study is to evaluate produced water as a supplemental source of water for the San Juan Generating Station (SJGS). This study incorporates elements that identify produced water volume and quality, infrastructure to deliver it to SJGS, t...

2004-01-01

79

Ozonated seawater induces genotoxicity and hematological alterations in turbot ( Scophthalmus maximus) — Implications for management of recirculation aquaculture systems  

Microsoft Academic Search

Ozonation has proven useful in recirculating aquaculture systems promoting the stabilization of water quality and disease control. Nevertheless, its cytogenetic and physiological effects on fish are still largely unknown. Hence, this research investigated the effects of ozone exposure in juvenile turbot (Scophthalmus maximus) by assessing its genotoxic potential (erythrocytic nuclear abnormalities — ENA — assay) and alterations on hematological parameters

J. Silva; A. Laranjeira; R. Serradeiro; M. A. Santos; M. Pacheco

2011-01-01

80

Effect of coagulation pretreatment on membrane distillation process for desalination of recirculating cooling water  

Microsoft Academic Search

The objective of this work was to study the performance of coagulation pretreatment and the effect of coagulation pretreatment on membrane distillation (MD) process for desalination of recirculating cooling water (RCW). In this study, RCW was desalinated by MD process after pretreated by coagulation, precision filtration, acidification and degassing. Pre-coagulation of RCW with poly-aluminum chloride (PACl) coagulant improves the elimination

Jun Wang; Dan Qu; Muer Tie; Haijing Ren; Xianjia Peng; Zhaokun Luan

2008-01-01

81

Equipment review: The molecular adsorbents recirculating system (MARS®)  

PubMed Central

The molecular adsorbents recirculating system (MARS®) is a form of artificial liver support that has the potential to remove substantial quantities of albumin-bound toxins that have been postulated to contribute to the pathogenesis of liver cell damage, haemodynamic instability and multi-organ failure in patients with acute liver failure (ALF) and acute-on-chronic liver failure (AoCLF). These toxins include fatty acids, bile acids, tryptophan, bilirubin, aromatic amino acids and nitric oxide. Data from controlled clinical trials are limited so far. One of two studies performed on small numbers of patients with AoCLF suggest a survival benefit, but no controlled data are available in the ALF setting. Our preliminary experience with MARS therapy, instituted late in the clinical course of five patients with severely impaired liver function, including three with AoCLF precipitated by sepsis and two with liver dysfunction due to sepsis in the absence of pre-existing chronic liver disease, indicates some clinical efficacy. However, the overall survival rate (1 of 5; 20%) remained poor. More data obtained from larger cohorts of patients enrolled in randomised controlled studies will be required in both the AoCLF and ALF settings to identify categories of liver failure patients who might benefit most from MARS treatment, to ascertain the most appropriate timing of intervention and to determine the overall impact on outcome, including cost-effectiveness.

Boyle, Martin; Kurtovic, Jelica; Bihari, David; Riordan, Stephen; Steiner, Christian

2004-01-01

82

Performance of the prototype gas recirculation system with built-in RGA for INO RPC system  

NASA Astrophysics Data System (ADS)

An open loop gas recovery and recirculation system has been developed for the INO RPC system. The gas mixture coming from RPC exhaust is first desiccated by passing through molecular sieve (3 Å+4 Å). Subsequent scrubbing over basic active alumina removes toxic and acidic contaminants. The Isobutane and Freon are then separated by diffusion and liquefied by fractional condensation by cooling up to -26C. A Residual Gas Analyser (RGA) is being used in the loop to study the performance of the recirculation system. The results of the RGA analysis will be discussed.

Bhuyan, M.; Datar, V. M.; Joshi, A.; Kalmani, S. D.; Mondal, N. K.; Rahman, M. A.; Satyanarayana, B.; Verma, P.

2012-01-01

83

Recirculating fluidized bed combustion system for a steam generator  

SciTech Connect

The invention comprises a steam generator fluidized bed which recirculates through a major portion of the normal gas to fluid heat transfer circuits. Solid bed material is separated, collected and recirculated. Bed temperatures are limited by regulation of density of bed inert material to inhibit the radiant aspects of combustion. Gas recirculation is used to supplement air flow to achieve higher than entrainment bed gas velocity in the fuel ignition and reaction zone. Fuel ignition and reaction are controlled by limiting the amount of atmospheric air flow to the circulating fuel rich bed mixture to regulate extent of propagation of the ignition and reaction zone into the initial portion of the circulating bed loop, starting from the point of highest gas pressure.

Strohmeyer, C. Jr.

1984-04-17

84

Hirameyo junkan roka yogyo system no sekkei to un'yo. (Design and operation of seawater recirculation fish culture system for Japanese flounder).  

National Technical Information Service (NTIS)

For developing a recirculation fish culture system for Japanese flounder, a pilot system of 20m(sup 3) of water was designed and constructed, and a verification test was conducted. The system comprises an FRP-made breeding tank, 6m in internal diameter an...

H. Honda K. Kikuchi Y. Watanabe N. Iwata S. Takeda

1994-01-01

85

KE basin recirculation/skimmer/IX systems restart acceptance test report  

SciTech Connect

The 105 KE Basin Recirculation System and Skimmer Loop have been upgraded to provide the flexibility to run the Ion Exchange Modules on either system to support spent fuel removal for the Spent Nuclear Fuel Project. This Acceptance Test Report Provides the documentation of the leak Testing for the construction work associated with the IXM inlet and outlet piping, places the cartridge filters back in service and provides the functional testing of the IXM`s on the recirculation and skimmer systems.

Derosa, D.C.

1996-03-27

86

Ornithinimicrobium tianjinense sp. nov., isolated from a recirculating aquaculture system.  

PubMed

A Gram-positive, strictly aerobic and heterotrophic, non-spore-forming actinobacterium (strain B2(T)) isolated from a recirculating aquaculture system was studied for its taxonomic position. Strain B2(T) formed a rudimentary substrate-mycelium that fragmented into short rod-shaped to coccoid cells (0.5 µm×0.5-2.2 µm or 0.5-1.0 µm in diameter). Colonies were yellow, smooth, circular and 1.5-2.0 mm in diameter after incubation on TSA for 3 days at 30 °C. Strain B2(T) grew at 20-40 °C (optimal, 30 °C) and pH 5.5-9.5 (optimal, 6.5-7.0) and in the presence of 0-9% (w/v) NaCl (optimal, 1%). The predominant menaquinone of strain B2(T) was MK-8(H4). The cell-wall peptidoglycan of strain B2(T) contained the amino acids ornithine, glutamic acid, alanine, glycine and aspartic acid. The major polar lipids were phosphatidylglycerol and diphosphatidylglycerol. The major fatty acids were iso-C15?:?0, iso-C16?:?0 and summed feature 9. Its DNA G+C content was 68.3 mol% (Tm). Analysis of 16S rRNA gene sequences indicated that strain B2(T) was related phylogenetically to members of the genus Ornithinimicrobium with highest similarity (96.6?%) to Ornithinimicrobium kibberense DSM 17687(T), followed by Ornithinimicrobium humiphilum DSM 12362(T) (96.3?%), Ornithinimicrobium pekingense LW6(T) (96.2%) and Ornithinimicrobium murale 01-Gi-040(T) (94.8%). On basis of phenotypic, chemotaxonomic and phylogenetic data, it was concluded that strain B2(T) represents a novel species of the genus Ornithinimicrobium, for which the name Ornithinimicrobium tianjinense sp. nov. is proposed. The type strain is B2(T) (?=CGMCC 1.12160(T)?=JCM 18464(T)). PMID:23907216

Liu, Liang-Zi; Liu, Ying; Chen, Zhu; Liu, Hong-Can; Zhou, Yu-Guang; Liu, Zhi-Pei

2013-12-01

87

Photobacterium aquae sp. nov., isolated from a recirculating mariculture system.  

PubMed

A Gram-staining-negative, heterotrophic, facultatively anaerobic bacterium, designated AE6(T), was isolated from a grouper (Epinephelus malabaricas) culture tank in a recirculating mariculture system located in Tianjin, China. Strain AE6(T) was able to grow at 15-40 °C (optimum, 30-35 °C), at pH 5.5-10.0 (optimum, pH 7.0-7.5) and in the presence of 0.5-7% (w/v) NaCl (optimum, 2-3%). It contained Q-8 as the predominant respiratory quinone, phosphatidylethanolamine (PE) and phosphatidylglycerol (PG) as the major polar lipids and C(16 : 1)?7c/C(16 : 1)?6c (40.4%), C(18 : 1)?7c (15.5%) and C(16 : 0) (13.5%) as the predominant cellular fatty acids. The genomic DNA G+C content was 47.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain AE6(T) belonged to the genus Photobacterium (94.2-96.8% of 16S rRNA gene sequence similarity) and formed a distinct phylogenetic lineage within the genus and exhibited the highest sequence similarity to Photobacterium aphoticum CECT 7614(T) (96.8%). Multilocus sequence analysis (MLSA) using four loci (gyrB, rpoA, pyrH and recA) also revealed that strain AE6(T) was phylogenetically related to the genus Photobacterium. Based on the phylogenetic, chemotaxonomic and phenotypic evidence, strain AE6(T) is considered to represent a novel species of the genus Photobacterium, for which the name Photobacterium aquae sp. nov. is proposed. The type strain is AE6(T) (?=?CGMCC 1.12159(T)?=?JCM 18480(T)). PMID:24096359

Liu, Ying; Liu, Liang-Zi; Song, Lei; Zhou, Yu-Guang; Qi, Fang-Jun; Liu, Zhi-Pei

2014-02-01

88

Final Environmental Assessment: Recirculation of Recaptured Water Year 2013-2017 San Joaquin River Restoration Program Flows.  

National Technical Information Service (NTIS)

Pursuant to the National Environmental Policy Act, the Department of the Interior, Bureau of Reclamation (Reclamation) is preparing this Final Environmental Assessment for the Recirculation of Recaptured Water Year 2013-2017 (Final WY 2013-2017 Recirculat...

2013-01-01

89

Internal dust recirculation system for a fluidized bed heat exchanger  

DOEpatents

A fluidized bed heat exchanger in which air is passed through a bed of particulate material containing fuel disposed in a housing. A steam/water natural circulation system is provided in a heat exchange relation to the bed and includes a steam drum disposed adjacent the bed and a tube bank extending between the steam drum and a water drum. The tube bank is located in the path of the effluent gases exiting from the bed and a baffle system is provided to separate the solid particulate matter from the effluent gases. The particulate matter is collected and injected back into the fluidized bed.

Gamble, Robert L. (Wayne, NJ) [Wayne, NJ; Garcia-Mallol, Juan A. (Morristown, NJ) [Morristown, NJ

1981-01-01

90

Chemical and sensory quantification of geosmin and 2-methylisoborneol in rainbow trout (Oncorhynchus mykiss) from recirculated aquacultures in relation to concentrations in basin water.  

PubMed

Globally, aquaculture systems with water recirculation experience increasing problems with microbial taste and odor compounds (TOCs) such as geosmin and 2-methylisoborneol (MIB). This study investigated the content of geosmin and MIB in water and the flesh of 200 rainbow trouts from eight recirculated aquaculture systems in Denmark. TOC content in the fish flesh was measured by a dynamic headspace extraction method and was evaluated by a sensory panel. The results showed significant correlations between TOC content in water and fish and between chemical analysis and sensory perception. When geosmin exceeded 20 ng/L in the water, 96% of the fish had an intense muddy flavor, but below 10 ng geosmin/L, 18% of the fish (only 3% in special depuration ponds) had an intense muddy flavor. The results indicate that TOC levels <10 ng/L will ensure that a negligible portion of the fish obtains an unpalatable taste and flavor due to TOCs. PMID:22040367

Petersen, Mikael A; Hyldig, Grethe; Strobel, Bjarne W; Henriksen, Niels H; Jørgensen, Niels O G

2011-12-14

91

Diagnosing system for an exhaust gas recirculation system of an automotive engine  

SciTech Connect

This patent describes a diagnosing system for an exhaust gas recirculation system having an EGR passage communicating an exhaust pipe of an engine with an intake passage of the engine, an EGR valve provided in the EGR passage, control means for opening the EGR valve in accordance with enigne operating conditions comprising: first means for detecting flow rate of recirculated gas in the EGR passage and for producing an actual EGR rate signal dependent on the flow rate; second means for producing a desired EGR rate signal including an allowable range in accordance with engine operating conditions; and third means responsive to the actual EGR rate signal and the desired EGR rate signal for producing a trouble signal as an alarm signal when the actual EGR rate signal is out of the allowable range.

Tamura, I.

1988-02-09

92

Demonstration of a Highly Efficient Solid Oxide Fuel Cell Power System Using Adiabatic Steam Reforming and Anode Gas Recirculation  

SciTech Connect

Solid oxide fuel cells (SOFC) are currently being developed for a wide variety of applications because of their high efficiency at multiple power levels. Applications for SOFCs encompass a large range of power levels including 1-2 kW residential combined heat and power applications, 100-250 kW sized systems for distributed generation and grid extension, and MW-scale power plants utilizing coal. This paper reports on the development of a highly efficient, small-scale SOFC power system operating on methane. The system uses adiabatic steam reforming of methane and anode gas recirculation to achieve high net electrical efficiency. The anode exit gas is recirculated and all of the heat and water required for the endothermic reforming reaction are provided by the anode gas emerging from the SOFC stack. Although the single-pass fuel utilization is only about 55%, because of the anode gas recirculation the overall fuel utilization is up to 93%. The demonstrated system achieved gross power output of 1650 to 2150 watts with a maximum net LHV efficiency of 56.7% at 1720 watts. Overall system efficiency could be further improved to over 60% with use of properly sized blowers.

Powell, Michael R.; Meinhardt, Kerry D.; Sprenkle, Vincent L.; Chick, Lawrence A.; Mcvay, Gary L.

2012-05-01

93

Effect of recirculation on organic matter removal in a hybrid constructed wetland system.  

PubMed

This research project aimed to determine the technologically feasible and applicable wastewater treatment systems which will be constructed to solve environmental problems caused by small communities in Turkey. Pilot-scale treatment of a small community's wastewater was performed over a period of more than 2 years in order to show applicability of these systems. The present study involves removal of organic matter and suspended solids in serially operated horizontal (HFCW) and vertical (VFCW) sub-surface flow constructed wetlands. The pilot-scale wetland was constructed downstream of anaerobic reactors at the campus of TUBITAK-MRC. Anaerobically pretreated wastewater was introduced into this hybrid two-stage sub-surface flow wetland system (TSCW). Wastewater was first introduced into the horizontal sub-surface flow system and then the vertical flow system before being discharged. Recirculation of the effluent was tested in the system. When the recirculation ratio was 100%, average removal efficiencies for TSCW were 91 +/- 4% for COD, 83 +/- 10% for BOD and 96 +/- 3% for suspended solids with average effluent concentrations of 9 +/- 5 mg/L COD, 6 +/- 3 mg/L BOD and 1 mg/L for suspended solids. Comparing non-recirculation and recirculation periods, the lowest effluent concentrations were obtained with a 100% recirculation ratio. The effluent concentrations met the Turkish regulations for discharge limits of COD, BOD and TSS in each case. The study showed that a hybrid constructed wetland system with recirculation is a very effective method of obtaining very low effluent organic matter and suspended solids concentrations downstream of anaerobic pretreatment of domestic wastewaters in small communities. PMID:21977661

Ayaz, S C; Findik, N; Akça, L; Erdo?an, N; Kinaci, C

2011-01-01

94

Solar hot water heating system  

Microsoft Academic Search

A solar hot water heating system is provided with solar collectors connected to a hot water storage tank with a recirculating pump to circulate the cooler water in the storage tank through the collector to absorb heat therefrom and to be returned to the storage tank. A plurality of temperature sensors are placed throughout the system to monitor various temperatures

J. V. Budzynski; D. A. James

1981-01-01

95

Numerical Recirculating Flow Calculation Using a Body-Fitted Coordinate System  

Microsoft Academic Search

A finite-difference algorithm for recirculating flow problem! in a body-fitted coordinate system is presented. A fully staggered grid system is adopted for the velocity components and the scalar variables. The strong conservation law form of the governing equations is written in the general curvilinear coordinates. The SIMPLE calculation procedure originally developed in Cartesian coordinates is extended to the present curvilinear

W. Shyy; S. S. Tong; S. M. Correa

1985-01-01

96

Fulminant hepatic failure following marijuana drug abuse: Molecular adsorbent recirculation system therapy  

PubMed Central

Marijuana is used for psychoactive and recreational purpose. We report a case of fulminant hepatic failure following marijuana drug abuse who recovered following artificial support systems for acute liver failure. There is no published literature of management of marijuana intoxication with molecular adsorbent recirculation system (MARS). MARS is effective and safe in patients with fulminant hepatic failure following marijuana intoxication.

Swarnalatha, G.; Pai, S.; Ram, R.; Dakshinamurty, K. V.

2013-01-01

97

Growth and survival of larval and juvenile cobia Rachycentron canadum in a recirculating raceway system  

Microsoft Academic Search

Cobia Rachycentron canadum is a fast-growing, pelagic marine species that has recently attracted aquaculturists in both the research and commercial sectors. The typical method of grow-out for this species is in outdoor systems where production is limited to locations and seasons conducive for adequate growth and survival. Expanding the culture of cobia to indoor recirculating aquaculture systems (RAS) would allow

Cynthia K. Faulk; Jeffrey B. Kaiser; G. Joan Holt

2007-01-01

98

Culture of Six Species of Bivalves in a Recirculating Seawater System.  

National Technical Information Service (NTIS)

The report presents the results of four experiments conducted in which six species of bivalve molluscs were reared for periods ranging from ten weeks to over two years in a recirculating seawater system. Shellfish were fed defined algal diets and had no a...

C. E. Epifanio C. M. Logan C. Turk

1975-01-01

99

Albumin dialysis and Molecular Adsorbents Recirculating System (MARS) for acute Wilson's disease  

Microsoft Academic Search

Wilson's disease presenting as acute liver failure (ALF) is potentially fatal, and liver transplantation (LTx) is the only option. We report two patients with Wilson's disease and ALF treated with the Molecular Adsorbents Recirculating System (MARS). Both patients fulfilled criteria for poor prognosis. Because LTx was not available immediately in either case, MARS was used as a bridge to LTx.

Sambit Sen; Marie Felldin; Christian Steiner; Bo Larsson; Godfrey T. Gillett; Michael Olausson; Roger Williams; Rajiv Jalan

2002-01-01

100

A nucleonic oil debris monitor for detecting metal in recirculating lubricating systems  

Microsoft Academic Search

Metallic debris sensors have been developed for recirculating oil lubrication systems. The in-line monitors apply the principle of X-ray fluorescence. The nucleonic oil debris monitors (ODM's) have been designed and fabricated for use with test cell operations involving aircraft transmissions and gear boxes. ODM's were tested to evaluate their sensitivity, accuracy, and response to lubricant temperature over the range of

R. W. Harman

1974-01-01

101

Experimental Bleaching of a Reef-Building Coral Using a Simplified Recirculating Laboratory Exposure System  

EPA Science Inventory

Determining stressor-response relationships in reef building corals is a critical need for researchers because of global declines in coral reef ecosystems. A simplified recirculating coral exposure system for laboratory testing of a diversity of species and morphologies of reef b...

102

Farming the Artificial Sea: Growth of Clams in a Recirculating Seawater System.  

National Technical Information Service (NTIS)

Eight groups of hatchery-reared clams were cultured for 22 weeks from setting in a recirculating seawater system. Each of the eight groups was fed a different diet. An extrapolated growth rate for the fastest growing group would yield animals with a shell...

M. Hartman C. E. Epifanio G. Pruder R. na

1975-01-01

103

Growth of juvenile cobia, Rachycentron canadum, at three different densities in a recirculating aquaculture system  

Microsoft Academic Search

Cobia (Rachycentron canadum) is an excellent aquaculture candidate and culture of this species continues to develop worldwide. Current culture practices generally include larviculture and production of early juveniles on land with final growout occurring in ocean cages. Data indicate that production and\\/or growout of juveniles in land based recirculating systems may be hampered by growth depression in fish held at

Kenneth A. Webb; Glenn M. Hitzfelder; Cynthia K. Faulk; G. Joan Holt

2007-01-01

104

[Performance of recirculating aquaculture systems in the intensive farming of Pacú Piaractus mesopotamicus (Characiformes: Characidae)].  

PubMed

An alternative to intensify fish production, reducing the environmental impact and production costs are recirculating aquaculture systems (RAS). The performance of a RAS was evaluated, as fish growth and water quality conditions, in a culture of Piaractus mesopotamicus reared for ornamental purposes. Two commercial food brands with different protein contents (18%-T1 and 28%-T2), were given to juvenile fishes during an eight weeks period. Growth was measured bi-weekly: standard length (Lp), peak height (A), weight and multiple condition factor (KM). The evaluation of water parameters included: dissolved oxygen, NH3-NH4, pH, NO2, NO3, KH carbonate hardness and PO4. NH3-N rate production was analyzed following Timmons-Ebeling model. Results demonstrated significant differences in weight only, and T2 showed a 7.5% higher value than T1; nevertheless, treatment T1 had a higher KM. In general, water quality values were suitable for growth: OD=T1: 4.23 +/- 1.23; T2: 4.13 +/- 0.86; NH3=T1: 0.02 +/- 0.02; T2: 0.06 +/- 0.10; however, pH was an exception (T1: 6.95 +/- 0.98; T2: 7.11 +/- 1.03), displaying lethal rates (<5) by the fifth week. Systems NH3 removal had a 99.4% to 100% efficiency. Final fish biomass was 22.03kg for T1 and 27.49kg for T2. We concluded that the systems were able to maintain suggested density up to the experimental fifth week. Water quality parameters remained in suitable levels, with the pH exception. Cultured fishes reached their commercial size (10cm) in eight weeks. PMID:22458232

Domínguez Castanedo, Omar; Martínez Espinosa, David Alberto

2012-03-01

105

A study on the optimal hydraulic loading rate and plant ratios in recirculation aquaponic system.  

PubMed

The growths of the African catfish (Clarias gariepinus) and water spinach (Ipomoea aquatica) were evaluated in recirculation aquaponic system (RAS). Fish production performance, plant growth and nutrient removal were measured and their dependence on hydraulic loading rate (HLR) was assessed. Fish production did not differ significantly between hydraulic loading rates. In contrast to the fish production, the water spinach yield was significantly higher in the lower hydraulic loading rate. Fish production, plant growth and percentage nutrient removal were highest at hydraulic loading rate of 1.28 m/day. The ratio of fish to plant production has been calculated to balance nutrient generation from fish with nutrient removal by plants and the optimum ratio was 15-42 gram of fish feed/m(2) of plant growing area. Each unit in RAS was evaluated in terms of oxygen demand. Using specified feeding regime, mass balance equations were applied to quantify the waste discharges from rearing tanks and treatment units. The waste discharged was found to be strongly dependent on hydraulic loading rate. PMID:19819130

Endut, Azizah; Jusoh, A; Ali, N; Wan Nik, W B; Hassan, A

2010-03-01

106

Performance degradation due to polarization effects in a dispersion-managed-soliton recirculating loop system  

Microsoft Academic Search

We investigate the performance degradation in dispersion-managed soliton systems caused by polarization-dependent loss and polarization-mode dispersion using a 600-km recirculating loop. We show that in an ultralong-haul transmission system, polarization effects can easily induce a variation in the bit-error rate (BER) greater than two orders of magnitude. In addition, polarization scattering caused by soliton collisions in wavelength-division-multiplexing systems makes the

Chongjin Xie; Andrew R. Grant; Linn F. Mollenauer; Xiang Liu

2004-01-01

107

Molecular absorbent recirculating system for the treatment of acute liver failure in surgical patients  

Microsoft Academic Search

The Molecular Adsorbent Recirculating System (MARS) represents an attractive artificial liver support system for the treatment\\u000a of liver insufficiency. However, neither indications for MARS treatment (i.e., after extended liver resection) nor criteria\\u000a for discontinuation of therapy have been evaluated. Therefore, we analyzed the clinical data of all our surgical patients\\u000a who received MARS treatment for acute liver failure (n =

Daniel Inderbitzin; Beat Muggli; Annette Ringger; Guido Beldi; Markus Gass; Beat Gloor; Dominik Uehlinger; Bruno Regli; Jürg Reichen; Daniel Candinas

2005-01-01

108

Integrated exhaust gas recirculation and charge cooling system  

DOEpatents

An intake system for an internal combustion engine comprises an exhaust driven turbocharger configured to deliver compressed intake charge, comprising exhaust gas from the exhaust system and ambient air, through an intake charge conduit and to cylinders of the internal combustion engine. An intake charge cooler is in fluid communication with the intake charge conduit. A cooling system, independent of the cooling system for the internal combustion engine, is in fluid communication with the intake charge cooler through a cooling system conduit. A coolant pump delivers a low temperature cooling medium from the cooling system to and through the intake charge cooler for the transfer of heat from the compressed intake charge thereto. A low temperature cooler receives the heated cooling medium through the cooling system conduit for the transfer or heat therefrom.

Wu, Ko-Jen

2013-12-10

109

Recirculating loop for experimental evaluation of EDFA saturated regime effects on optical communication systems  

Microsoft Academic Search

We demonstrate an optical-fiber recirculating loop for experimental simulation of long-haul optical communication systems using cascaded erbium-doped fiber amplifiers (EDFA's) operating in the gain saturation regime. The loop contains sections of dispersion shifted fibers (DSF's), standard fiber, and a set of in-line devices, such as tuning filters, optical amplifiers, polarization controllers, and a variable attenuator. The main results presented here

Claudio Mazzali; Hugo L. Fragnito

1998-01-01

110

77 FR 19740 - Water Sources for Long-Term Recirculation Cooling Following a Loss-of-Coolant Accident  

Federal Register 2010, 2011, 2012, 2013

The U.S. Nuclear Regulatory Commission (NRC or the Commission) is issuing a revision to Regulatory Guide (RG) 1.82, ``Water Sources for Long-Term Recirculation Cooling Following a Loss-of-Coolant Accident.'' RG 1.82 describes methods that the NRC staff considers acceptable to implement requirements regarding the sumps and suppression pools that provide water sources for emergency core cooling,......

2012-04-02

111

Prediction of central recirculation zone size for a complete burner-quarl-furnace system  

SciTech Connect

In the swirl flow burning process of fuels, the central recirculation zone plays an important role in flame stabilization by providing a hot flow of recirculated combustion products, which reduce both the length of flame and the stabilized flame distance from the burner mouth. In this paper, a new modified swirl number, S exp xx, related to the characteristic size of the burner quarl, is introduced to correlate the isothermal and burning flows. Using a well-known two-dimensional computational model, the isothermal flow pattern in a complete burner-quarl-furnace system is computed. On this basis, the theoretical swirl number S exp xx is calculated and used as a correlation parameter for predicting the central recirculation zone size in burning flow conditions. Experimental tests for both nonreacting and reacting flows on the same complete burner-quarl-furnace system, for comparing the theoretical and experimental swirl number s exp xx, have been conducted, and the validity of this new correlation parameter has been proved. 11 references.

Cristea, E.B.

1987-03-01

112

Optimization and evaluation of a bottom substrate denitrification tank for nitrate removal from a recirculating aquaculture system.  

PubMed

A bottom substrate denitrification tank for a recirculating aquaculture system was developed. The laboratory scale denitrification tank was an 8 L tank (0.04 m2 tank surface area), packed to a depth of 5 cm with a bottom substrate for natural denitrifying bacteria. An aquarium pump was used for gentle water mixing in the tank; the dissolved oxygen in the water was maintained in aerobic conditions (e.g. > 2 mg/L) while anoxic conditions predominated only at the bottom substrate layer. The results showed that, among the four substrates tested (soil, sand, pumice stone and vermiculite), pumice was the most preferable material. Comparing carbon supplementation using methanol and molasses, methanol was chosen as the carbon source because it provided a higher denitrification rate than molasses. When methanol was applied at the optimal COD:N ratio of 5:1, a nitrate removal rate of 4591 +/- 133 mg-N/m2 tank bottom area/day was achieved. Finally, nitrate removal using an 80 L denitrification tank was evaluated with a 610 L recirculating tilapia culture system. Nitrate treatment was performed by batch transferring high nitrate water from the nitrification tank into the denitrification tank and mixing with methanol at a COD:N ratio of 5:1. The results from five batches of nitrate treatment revealed that nitrate was successfully removed from water without the accumulation of nitrite and ammonia. The average nitrate removal efficiency was 85.17% and the average denitrification rate of the denitrification tank was 6311 +/- 945 mg-N/m2 tank bottom area/day or 126 +/- 18 mg-N/L of pumice packing volume/day. PMID:24520693

Pungrasmi, Wiboonluk; Playchoom, Cholticha; Powtongsook, Sorawit

2013-08-01

113

Parameters affecting HS emissions removal and re-circulating water quality in a pilot-scale sequential biological treatment system at a wastewater lift station in Brownsville, Texas, USA  

Microsoft Academic Search

In this study, a pilot-scale sequential biological treatment system combining a biotrickling filter and biofilter was used to optimize the removal of variable emission H2S loadings ranging from 30 to 120 g m hat a wastewater lift station in Brownsville, Texas USA. The biotrickling filter recycle water pH remained between 2.0 to 3.0 during the four months of unit operation

Anand K. Karre; Pavan Bairu; Kim D. Jones; Jan Paca

2012-01-01

114

Albumin dialysis with molecular adsorbent recirculating system (MARS) for the treatment of hepatic encephalopathy in liver failure.  

PubMed

Acute, acute-on-chronic and chronic liver diseases are major health issues worldwide, and most cases end with the need for liver transplantation. Up to 90% of the patients die waiting for an organ to be transplanted. Hepatic encephalopathy is a common neuropsychiatric syndrome that usually accompanies liver failure and impacts greatly on the quality of life. The molecular adsorbent recirculating system (MARS) is a recently developed form of artificial liver support that functions on a base of albumin dialysis. It facilitates the dialysis of albumin-bound and water-soluble toxins, allowing the patient to survive and even improving some clinical features of liver failure. The following manuscript reviews the technical features of MARS operation and some of the clinical trials that analyze the efficacy of the system in the therapy of liver diseases. PMID:22228886

Kobashi-Margáin, Ramón A; Gavilanes-Espinar, Juan G; Gutiérrez-Grobe, Ylse; Gutiérrez-Jiménez, Angel A; Chávez-Tapia, Norberto; Ponciano-Rodríguez, Guadalupe; Uribe, Misael; Méndez Sánchez, Nahum

2011-06-01

115

Development and design of a fluidized bed/upflow sand filter configuration for use in recirculating aquaculture systems  

SciTech Connect

A fluidized bed/upflow sand filter configuration, was developed and designed for utilization in recirculating aquaculture system, specifically the soft-shell crab and soft-shell crawfish industries. These filters were selected and designed because of their ability to withstand clogging and still maintain high levels of water quality for aquaculture production. The effectiveness of sand grain size was used to evaluate fluidized bed filter performance with filter loadings ranging from 16 to 1285 pounds of crawfish per cubic foot of filter sand. A coarse sand grain size was recommended as a filter media because of it's ability to shear excessive biofilm growth from the and, thus prohibiting clogging from occurring within the filter bed. The fluidized bed/upflow sand filter combination was evaluated in terms of nitrification and oxygen consumption when used with a recirculating crab shedding system. The filter combination's carrying capacity (700 crabs per cubic foot of sand media) exceeded that observed with the submerged rock filter by more than 20 times and was largely explained by the filter's solids removal ability which significantly reduced the filter's oxygen loading rate (OLR). Nitrification rates with the filter combination were extremely high as total ammonia and nitrite levels remained below 1.0 mg-N/l. Verification of a volumetric loading criteria (150 pounds per cubic foot) for this filter combination was further established with performance data obtained from a commercial soft-shell crawfish facility. Water quality monitoring results indicated that the filters maintained total ammonia and nitrite levels below 1.0 mg-N/l under typical operating conditions. Shock loading, pH control, and over-feeding, rather than filter capacity, dominated water quality fluctuations, thereby indicating that the loading criteria was sufficient for commercial operation.

Burden, D.G.

1988-01-01

116

Diagnosing system for an exhaust gas recirculation system of an automotive engine  

SciTech Connect

A diagnosing system is described for an exhaust gas recirculation system, comprising: means for detecting the position of the EGR valve and for producing a position signal dependent on the position of the EGR valve; and trouble detector means responsive to the valve operating signal and to the position signal for producing a trouble signal as an alarm signal when the detecting means produces a position signal of an actual closed state of the EGR value and the control means produces a valve operating signal representing an open state of the EGR valve. The detecting means is a photoelectric transducer, the photoelectric transducer comprises a photodiode and a phototransistor, and the transducer includes a shaft connected to a valve body of the EGR valve. The shaft is movable by movement of the valve body into a path between the photodiode and phototransistor, and the transducer includes a U-shaped holder having the photodiode and phototransistor facing each other on arms of the holder.

Ichikawa, K.

1989-04-25

117

Improving hollow fiber dialyzer efficiency with a recirculating dialysate system. I: Theory and applicability.  

PubMed

The mathematical theory that underlies a novel non-regenerated recirculating dialysate system (RDS) for improving diffusive clearance in hemodialyzers is presented. The theory states the conditions that hemodialyzers must meet to be suitable in RDS optimization. We have verified the applicability of the RDS for several Cuprophan and polysulfone (PS) commercial dialyzers, showing that PS (synthetic) membranes achieve the highest increments of diffusive clearance. A numerical simulation analysis over more general conditions defined by the dimensionless groups of the system demonstrated that the highest diffusive clearance improvements are achieved in dialyzers operating with a low value of the diffusive mass-transfer area/blood flow rate ratio. This study has provided the base for the assessment of the performance of the RDS as compared to several high-efficiency systems, presented in Part II of this work [M. Prado, L. M. Roa, A. Palma, and J. A. Milan, Ann. Biomed. Eng. (2004) submitted]. PMID:15981864

Prado, Manuel; Roa, Laura M; Palma, Alfonso; Milán, José A

2005-05-01

118

Effect of stocking density on performances of juvenile turbot ( Scophthalmus maximus) in recirculating aquaculture systems  

NASA Astrophysics Data System (ADS)

Limited information has been available about the influence of loading density on the performances of Scophthalmus maximus, especially in recirculating aquaculture systems (RAS). In this study, turbot (13.84±2.74 g; average weight±SD) were reared at four different initial densities (low 0.66, medium 1.26, sub-high 2.56, high 4.00 kg/m2) for 10 weeks in RAS at 23±1°C. Final densities were 4.67, 7.25, 14.16, and 17.47 kg/m2, respectively, which translate to 82, 108, 214, and 282 percent coverage of the tank bottom. Density had both negative and independent impacts on growth. The final mean weight, specific growth rate (SGR), and voluntary feed intake significantly decreased and the coefficient of variation (CV) of final body weight increased with increase in stocking density. The medium and sub-high density groups did not differ significantly in SGR, mean weight, CV, food conversion rate (FCR), feed intake, blood parameters, and digestive enzymes. The protease activities of the digestive tract at pH 7, 8.5, 9, and 10 were significantly higher for the highest density group, but tended to be lower (not significantly) at pH 4 and 8.5 for the lowest density group. The intensity of protease activity was inversely related to feed intake at the different densities. Catalase activity was higher (but not significantly) at the highest density, perhaps because high density started to induce an oxidative effect in turbot. In conclusion, turbot can be cultured in RAS at a density of less than 17.47 kg/m2. With good water quality and no feed limitation, initial density between 1.26 and 2.56 kg/m2 (final: 7.25 and 14.16 kg/m2) would not negatively affect the turbot cultured in RAS. For culture at higher density, multi-level feeding devices are suggested to ease feeding competition.

Li, Xian; Liu, Ying; Blancheton, Jean-Paul

2013-05-01

119

Advanced water iodinating system. [for potable water aboard manned spacecraft  

NASA Technical Reports Server (NTRS)

Potable water stores aboard manned spacecraft must remain sterile. Suitable sterilization techniques are needed to prevent microbial growth. The development of an advanced water iodinating system for possible application to the shuttle orbiter and other advanced spacecraft, is considered. The AWIS provides a means of automatically dispensing iodine and controlling iodination levels in potable water stores. In a recirculation mode test, simulating application of the AWIS to a water management system of a long term six man capacity space mission, noniodinated feed water flowing at 32.2 cu cm min was iodinated to 5 + or - ppm concentrations after it was mixed with previously iodinated water recirculating through a potable water storage tank. Also, the AWIS was used to successfully demonstrate its capability to maintain potable water at a desired I2 concentration level while circulating through the water storage tank, but without the addition of noniodinated water.

Davenport, R. J.; Schubert, F. H.; Wynveen, R. A.

1975-01-01

120

Advances in rearing cobia Rachycentron canadum larvae in recirculating aquaculture systems: Live prey enrichment and greenwater culture  

Microsoft Academic Search

Cobia Rachycentron canadum is a relatively hardy species which exhibits high rates of growth during the larval and juvenile periods. Currently, this species is considered to be a good candidate for commercial production in recirculating aquaculture systems. However, little information is available regarding the nutritional requirements of cobia larvae in such systems, and this information is required to advance commercial

Cynthia K. Faulk; G. Joan Holt

2005-01-01

121

Prediction of central recirculation zone size for a complete burner-quarl-furnace system  

Microsoft Academic Search

In the swirl flow burning process of fuels, the central recirculation zone plays an important role in flame stabilization by providing a hot flow of recirculated combustion products, which reduce both the length of flame and the stabilized flame distance from the burner mouth. In this paper, a new modified swirl number, S exp xx, related to the characteristic size

Eugen-Dan B. Cristea

1987-01-01

122

Nuclear reactor coolant recirculation  

SciTech Connect

A system is described for forcing a liquid water coolant to recirculate through an unshrouded nuclear core in a pressure vessel. The core includes an array of spaced fuel assemblies supported between a lower core support member and an upper core support member. Each of the fuel assemblies is fitted with a tubular flow channel for containing water coolant flowing therethrough; an annular lower support ring attached to the pressure vessel and connected to the lower core support member for support thereof. The lower core support member, the lower support ring and the lower part of the pressure vessel form a lower plenum wherein the coolant can be pressurized. An upper support ring is attached to the pressure vessel and connected to the upper core support member. A space in the pressure vessel above the upper core support member forms an upper plenum for containing water coolant. Coolant pressurizers within the pressure vessel each have a coolant inlet and a coolant outlet and vertically oriented elongated coolant conducts conduits positioned in radially spaced relation between the core and the inner wall of the pressure vessel and extends from the upper plenum to the lower plenum. Each is connected to the coolant inlet of a respective one of the coolant pressurizers and each penetrates the upper support ring for conducting coolant from the upper plenum to the coolant inlet. The coolant outlet of each coolant pressurizer is in fluid communication with the lower plenum for pressurizing the coolant therein. Primary coolant passages are through the lower support member for admitting a pressurized coolant from the lower plenum into the fuel assemblies; and coolant outlet means at the upper end of the core are for discharging liquid coolant from the core to the upper plenum whereby the coolant is recirculated from the lower plenum, through the core to the upper plenum and back to the lower plenum.

Hobson, R.R.

1987-09-29

123

Effects of two different ozone doses on seawater recirculating systems for black sea bream Acanthopagrus schlegeli (Bleeker): Removal of solids and bacteria by foam fractionation  

Microsoft Academic Search

Foam fractionators, with and without additional ozonation, were evaluated for their effect on solids removal (suspended solids, SS; volatile suspended solids, VSS; dissolved organic carbon, DOC), particle size distribution of the foam in seawater recirculating systems during a 44-day experimental period. The effect of ozone on heterotrophic bacteria was also quantified in the entire system. Three separate but identical recirculating

Youhee Kim; Pyong-Kih Kim; Harry V. Daniels

2011-01-01

124

Comparison of aerobically-treated and untreated crop residue as a source of recycled nutrients in a recirculating hydroponic system  

NASA Technical Reports Server (NTRS)

This study compared the growth of potato plants on nutrients recycled from inedible potato biomass. Plants were grown for 105 days in recirculating, thin-film hydroponic systems containing four separate nutrient solution treatments: (1) modified half-strength Hoagland's (control), 2) liquid effluent from a bioreactor containing inedible potato biomass, 3) filtered (0.2 micrometer) effluent, and 4) the water soluble fraction of inedible potato biomass (leachate). Approximately 50% of the total nutrient requirement in treatments 2-4 were provided (recycled) from the potato biomass. Leachate had an inhibitory effect on leaf conductance, photosynthetic rate, and growth (50% reduction in plant height and 60% reduction in tuber yield). Plants grown on bioreactor effluent (filtered or unfiltered) were similar to the control plants. These results indicated that rapidly degraded, water soluble organic material contained in the inedible biomass, i.e., material in leachate, brought about phytotoxicity in the hydroponic culture of potato. Recalcitrant, water soluble organic material accumulated in all nutrient recycling treatments (650% increase after 105 days), but no increase in rhizosphere microbial numbers was observed.

Mackowiak, C. L.; Garland, J. L.; Strayer, R. F.; Finger, B. W.; Wheeler, R. M.

1996-01-01

125

Survival and Growth of Striped Bass, 'Morone saxatilis' (Walbaum) Fry Fed Artificial Diets in a Closed Recirculating System.  

National Technical Information Service (NTIS)

Seven artificial diets were tested for their suitability as a first food for striped bass fry in experiments conducted in a closed, recirculating system at the Auburn University Fisheries Research Unit. Three 15-day tests were conducted between 6 April an...

J. R. Bowman

1979-01-01

126

Transport behavior of surrogate biological warfare agents in a simulated landfill: effect of leachate recirculation and water infiltration.  

PubMed

An understanding of the transport behavior of biological warfare (BW) agents in landfills is required to evaluate the suitability of landfills for the disposal of building decontamination residue (BDR) following a bioterrorist attack on a building. Surrogate BW agents, Bacillus atrophaeus spores and Serratia marcescens, were spiked into simulated landfill reactors that were filled with synthetic building debris (SBD) and operated for 4 months with leachate recirculation or water infiltration. Quantitative polymerase chain reaction (Q-PCR) was used to monitor surrogate transport. In the leachate recirculation reactors, <10% of spiked surrogates were eluted in leachate over 4 months. In contrast, 45% and 31% of spiked S. marcescens and B. atrophaeus spores were eluted in leachate in the water infiltration reactors. At the termination of the experiment, the number of retained cells and spores in SBD was measured over the depth of the reactor. Less than 3% of the total spiked S. marcescens cells and no B. atrophaeus spores were detected in SBD. These results suggest that significant fractions of the spiked surrogates were strongly attached to SBD. PMID:20973546

Saikaly, Pascal E; Hicks, Kristin; Barlaz, Morton A; de Los Reyes, Francis L

2010-11-15

127

High ratio recirculating gas compressor  

SciTech Connect

A high ratio positive displacement recirculating rotary compressor is disclosed. The compressor includes an integral heat exchanger and recirculation conduits for returning cooled, high pressure discharge gas to the compressor housing to reducing heating of the compressor and enable higher pressure ratios to be sustained. The compressor features a recirculation system which results in continuous and uninterrupted flow of recirculation gas to the compressor with no direct leakage to either the discharge port or the intake port of the compressor, resulting in a capability of higher sustained pressure ratios without overheating of the compressor.

Weinbrecht, John F. (601 Oakwood Pl., NE., Albuquerque, NM 87123)

1989-01-01

128

Depletion of florfenicol amine in tilapia (Oreochromis sp.) maintained in a recirculating aquaculture system following Aquaflor®-medicated feed therapy  

USGS Publications Warehouse

Aquaflor® [50% w w?1 florfenicol (FFC)], is approved for use in freshwater-reared warmwater finfish which include tilapia Oreochromis spp. in the United States to control mortality from Streptococcus iniae. The depletion of florfenicol amine (FFA), the marker residue of FFC, was evaluated after feeding FFC-medicated feed to deliver a nominal 20 mg FFC kg?1 BW d?1 dose (1.33× the label use of 15 mg FFC kg?1 BW d?1) to Nile tilapia O. niloticus and hybrid tilapia O. niloticus × O. aureus held in a recirculating aquaculture system (RAS) at production-scale holding densities. Florfenicol amine concentrations were determined in fillets taken from 10 fish before dosing and from 20 fish at nine time points after dosing (from 1 to 240 h post-dosing). Water samples were assayed for FFC before, during and after the dosing period. Parameters monitored included daily feed consumption and biofilter function (levels of ammonia, nitrite and nitrate). Mean fillet FFA concentration decreased from 13.77 ?g g?1 at 1-h post dosing to 0.39 ?g g?1 at 240-h post dosing. Water FFC concentration decreased from a maximum of 1400 ng mL?1 at 1 day post-dosing to 847 ng mL?1 at 240 h post-dosing. There were no adverse effects noted on fish, feed consumption or biofilter function associated with FFC-medicated feed administration to tilapia.

Gaikowski, Mark P.; Whitsel, Melissa K.; Charles, Shawn; Schleis, Susan M.; Crouch, Louis S.; Endris, Richard G.

2013-01-01

129

Application of CFD modeling to hydrodynamics of CycloBio fluidized sand bed in recirculating aquaculture systems  

NASA Astrophysics Data System (ADS)

To improve the efficiency of a CycloBio fluidized sand bed (CB FSB) in removal of dissolved wastes in recirculating aquaculture systems, the hydrodynamics of solid-liquid flow was investigated using computational fluid dynamics (CFD) modeling tools. The dynamic characteristics of silica sand within the CB FSB were determined using three-dimensional, unsteady-state simulations with the granular Eulerian multiphase approach and the RNG k-? turbulence model, and the simulation results were validated using available lab-scale measurements. The bed expansion of CB FSB increased with the increase in water inflow rate in numerical simulations. Upon validation, the simulation involving 0.55 mm particles, the Gidaspow correlation for drag coefficient model and the Syamlal-O'Brien correlation for kinetic granular viscosity showed the closest match to the experimental results. The volume fraction of numerical simulations peaked as the wall was approached. The hydrodynamics of a pilot-scale CB FSB was simulated in order to predict the range of water flow to avoid the silica sand overflowing. The numerical simulations were in agreement with the experimental results qualitatively and quantitatively, and thus can be used to study the hydrodynamics of solid-liquid multiphase flow in CB FSB, which is of importance to the design, optimization, and amplification of CB FSBs.

Liu, Yao; Song, Xiefa; Liang, Zhenlin; Peng, Lei

2013-11-01

130

Method for preventing oxygen corrosion in a boiling water nuclear reactor and improved boiling water reactor system  

Microsoft Academic Search

This patent describes a method for prevention of corrosion, due to oxygen activity, in a boiling water nuclear reactor system having a main feedwater recirculation loop comprising a reactor vessel with a reactor core and with a steam off-take line and a condensate return line in flow communication with the vessel for recirculating feedwater between the reactor and a steam

Desilva

1989-01-01

131

Advanced Horizontal Well Recirculation Systems for Geothermal Energy Recovery in Sedimentary Formations  

SciTech Connect

There is increased recognition that geothermal energy resources are more widespread than previously thought, with potential for providing a significant amount of sustainable clean energy worldwide. Recent advances in drilling, completion, and production technology from the oil and gas industry can now be applied to unlock vast new geothermal resources, with some estimates for potential electricity generation from geothermal energy now on the order of 2 million megawatts. Terralog USA, in collaboration with the University of California, Irvine (UCI), are currently investigating advanced design concepts for paired horizontal well recirculation systems, optimally configured for geothermal energy recovery in permeable sedimentary and crystalline formations of varying structure and material properties. This two-year research project, funded by the US Department of Energy, includes combined efforts for: 1) Resource characterization; 2) Small and large scale laboratory investigations; 3) Numerical simulation at both the laboratory and field scale; and 4) Engineering feasibility studies and economic evaluations. The research project is currently in its early stages. This paper summarizes our technical approach and preliminary findings related to potential resources, small-scale laboratory simulation, and supporting numerical simulation efforts.

Mike Bruno; Russell L. Detwiler; Kang Lao; Vahid Serajian; Jean Elkhoury; Julia Diessl; Nicky White

2012-09-30

132

Intake manifold for internal combustion engine having exhaust gas recirculation system  

SciTech Connect

An intake manifold is described of an internal combustion engine which has an exhaust gas recirculation system. It introduces a part of exhaust gas from an exhaust passage through an EGR gas supply passage into the intake manifold. The intake manifold is provided with an EGR gas outlet opened thereto and connected to the EGR gas supply passage. The EGR gas outlet is located in an upper section of an interior of the intake manifold. A part of the EGR gas supply passage, in the vicinity of the EGR gas outlet extends transversely along a side-to-top wall of the intake manifold. The part of EGR gas passage defines at an opposite side thereof an inclined inner wall along the side-to-top wall of the intake manifold, in a transverse cross-section of the intake manifold. The inclined inner wall has its top portion directed downward to define the EGR gas outlet, so that the EGR gas outlet is defined below an inner surface of the top wall of the inner intake manifold.

Yokoi, T.; Takeya, E.; Hattori, K.; Abe, K.; Osawa, H.

1987-06-16

133

Improving methane production and phosphorus release in anaerobic digestion of particulate saline sludge from a brackish aquaculture recirculation system.  

PubMed

In this study, batch tests were conducted to examine the effects of trehalose and glycine betaine as well as potassium on the specific methanogenic activity (SMA), acid and alkaline phosphatase activity of anaerobic biomass and phosphorus release in anaerobic digestion of saline sludge from a brackish recirculation aquaculture system. The results of ANOVA and Tukey's HSD (honestly significant difference) tests showed that glycine betaine and trehalose enhanced SMA of anaerobic biomass and reactive phosphorus release from the particulate waste. Moreover, SMA tests revealed that methanogenic sludge, which was long-term acclimatized to a salinity level of 17g/L was severely affected by the increase in salinity to values exceeding 35g/L. Addition of compatible solutes, such as glycine betaine and trehalose, could be used to enhance the specific methane production rate and phosphorus release in anaerobic digestion from particulate organic waste produced in marine or brackish aquaculture recirculation systems. PMID:24785791

Zhang, Xuedong; Ferreira, Rui B; Hu, Jianmei; Spanjers, Henri; van Lier, Jules B

2014-06-01

134

Successful Treatment of an Adult with Amanita Phalloides - Induced Fulminant Liver Failure with Molecular Adsorbent Recirculating System (MARS)  

Microsoft Academic Search

Despite significant advances in intensive care management of Amanita phalloides-induced fulminant liver failure (FLF), patients with this condition still have a high mortality rate in the absence of orthotopic liver transplantation. Molecular Adsorbent Recirculating System (MARS) is a new, cell-free, extracorporeal liver assistance method utilizing an albumin dialysate for the removal of albumin-bound toxins, and a highly effective depurative therapy

Cãtãlina Lionte

135

Study of system performance in a 107-km dispersion-managed recirculating loop due to polarization effects  

Microsoft Academic Search

We investigate the polarization evolution for both signal and noise in two 107-km recirculating loops with polarization-dependent loss per round-trip of 0.35 dB and less than 0.1 dB, respectively. When the system is optimized, in the first case, both signal and noise are polarized, while in the second case, the signal tends to depolarize due to the noise. We experimentally

Yu Sun; Hua Jiao; Jipeng Wen; Hai Xu; Heider Ereifej; Gary M. Carter; Curtis R. Menyuk

2001-01-01

136

Molecular adsorbent recirculating system dialysis in patients with acute liver failure who are assessed for liver transplantation  

Microsoft Academic Search

Objective  To assess the usefulness of dialysis with the molecular adsorbent recirculating system (MARS) in patients with acute liver failure who fulfil criteria for liver transplantation.Design  Observational cohort study.Setting  ICU at a liver transplantation centre.Patients  Twenty-two patients (23 episodes) received MARS dialysis. They were either listed for LT (n?=?14), delayed (n?=?1), or not listed (contra-indication, n?=?7).Interventions  A total of 56 MARS treatments (median per patient 2; mean

Christophe Camus; Sylvain Lavoué; Arnaud Gacouin; Yves Le Tulzo; Richard Lorho; Karim Boudjéma; Christian Jacquelinet; Rémi Thomas

2006-01-01

137

Use of the molecular adsorbents recirculating system as a treatment for acute decompensated Wilson disease.  

PubMed

Acute decompensated Wilson disease presenting as fulminant liver failure is a life-threatening condition for which liver transplantation is the ultimate treatment. It is listed as a status 1 indication according to the United Network for Organ Sharing classification. A massive amount of copper released during the attack induces hemolytic anemia and acute renal failure. Conventional chelating therapy attempting to remove copper from the patient is not satisfactory because there is inadequate time for these drugs to take action and patients are usually oliguric. The Molecular Adsorbents Recirculating System (MARS) is a form of modified dialysis that removes putative albumin-bound toxins associated with liver failure. It is believed that extracorporeal albumin dialysate absorbs the circulating copper molecules that are trapped in the patient's circulation. We report 2 patients with acute decompensated Wilson disease treated with MARS. In the first case, the patient was started on MARS once conventional treatment failed. A significant amount of copper was removed from her circulatory system, and her condition stabilized afterwards. The treatment gained her extra time, and she was eventually bridged to liver transplantation. In the second case, the patient was started on MARS treatment early in the course of his illness, and his condition soon stabilized after the treatment. He was able to return to his home country for liver transplantation. In both cases, MARS was used as a means of preventing deterioration rather than salvaging devastation. In conclusion, MARS may confer benefits to patients with acute decompensated Wilson disease if it is started early in the course of illness. PMID:18825711

Chiu, Alexander; Tsoi, Nai Shun; Fan, Sheung Tat

2008-10-01

138

Simultaneous water desalination and electricity generation in a microbial desalination cell with electrolyte recirculation for pH control.  

PubMed

A recirculation microbial desalination cell (rMDC) was designed and operated to allow recirculation of solutions between the anode and cathode chambers. This recirculation avoided pH imbalances that could inhibit bacterial metabolism. The maximum power density was 931±29mW/m(2) with a 50mM phosphate buffer solution (PBS) and 776±30mW/m(2) with 25mM PBS. These power densities were higher than those obtained without recirculation of 698±10mW/m(2) (50mM PBS) and 508±11mW/m(2) (25mM PBS). The salt solution (20g/L NaCl) was reduced in salinity by 34±1% (50mM) and 37±2% (25mM) with recirculation (rMDC), and by 39±1% (50mM) and 25±3% (25mM) without recirculation (MDC). These results show that electrolyte recirculation using an rMDC is an effective method to increase power and achieve efficient desalination by eliminating pH imbalances. PMID:22200556

Qu, Youpeng; Feng, Yujie; Wang, Xin; Liu, Jia; Lv, Jiangwei; He, Weihua; Logan, Bruce E

2012-02-01

139

Bacterially mediated removal of phosphorus and cycling of nitrate and sulfate in the waste stream of a "zero-discharge" recirculating mariculture system.  

PubMed

Simultaneous removal of nitrogen and phosphorus by microbial biofilters has been used in a variety of water treatment systems including treatment systems in aquaculture. In this study, phosphorus, nitrate and sulfate cycling in the anaerobic loop of a zero-discharge, recirculating mariculture system was investigated using detailed geochemical measurements in the sludge layer of the digestion basin. High concentrations of nitrate and sulfate, circulating in the overlying water (?15 mM), were removed by microbial respiration in the sludge resulting in a sulfide accumulation of up to 3 mM. Modelling of the observed S and O isotopic ratios in the surface sludge suggested that, with time, major respiration processes shifted from heterotrophic nitrate and sulfate reduction to autotrophic nitrate reduction. The much higher inorganic P content of the sludge relative to the fish feces is attributed to conversion of organic P to authigenic apatite. This conclusion is supported by: (a) X-ray diffraction analyses, which pointed to an accumulation of a calcium phosphate mineral phase that was different from P phases found in the feces, (b) the calculation that the pore waters of the sludge were highly oversaturated with respect to hydroxyapatite (saturation index = 4.87) and (c) there was a decrease in phosphate (and in the Ca/Na molar ratio) in the pore waters simultaneous with an increase in ammonia showing there had to be an additional P removal process at the same time as the heterotrophic breakdown of organic matter. PMID:24657541

Krom, M D; Ben David, A; Ingall, E D; Benning, L G; Clerici, S; Bottrell, S; Davies, C; Potts, N J; Mortimer, R J G; van Rijn, J

2014-06-01

140

Phosphatase activity and specific methanogenic activity in an anaerobic reactor treating sludge from a brackish recirculation aquaculture system.  

PubMed

Anaerobic treatment of high salinity sludge from marine/brackish recirculation aquaculture systems is potentially limited by inhibition of enzymatic activities and cell lysis resulting from high osmotic pressures. To further address these limitations the following investigations were conducted: effect of salinity on phosphatase activity (PA), soluble microbial products (SMP) production, and presence of extracellular polymeric substances (EPS); effect of iron (III) chloride (FeCl3) on PA and specific methanogenic activity (SMA); effect of addition of the compatible solute glycine betaine (GB) and potassium on PA, as well as on SMP and EPS production, all under saline conditions. The results show that salinity has different effects on PA of anaerobes under starvation and feeding conditions. FeCl3 increased the SMA of the sludge by 22.5% at 100 mg FeCl3/L compared with a control group (0 mg FeCl3/L). Furthermore, results of analysis of variance tests show that betaine increased the polysaccharide content of EPS and polypeptide content of SMP. However, addition of 1 mM potassium chloride did not show a significant effect on EPS and SMP composition. In conclusion, anaerobic digestion of salty sludges from a brackish aquaculture recirculation system may not be negatively affected by FeCl3 addition to concentrate waste streams, whereas GB boosts the production of SMP and EPS. PMID:23863432

Zhang, Xuedong; Ferreira, Rui B; Spanjers, Henri; van Lier, Jules B

2013-01-01

141

Implementation of an experimental pilot reproducing the fouling of the exhaust gas recirculation system in diesel engines  

NASA Astrophysics Data System (ADS)

The European emission standards EURO 5 and EURO 6 define more stringent acceptable limits for exhaust emissions of new vehicles. The Exhaust Gas Recirculation (EGR) system is a partial but essential solution for lowering the emission of nitrogen oxides and soot particulates. Yet, due to a more intensive use than in the past, the fouling of the EGR system is increased. Ensuring the reliability of the EGR system becomes a main challenge. In partnership with PSA Peugeot Citroën, we designed an experimental setup that mimics an operating EGR system. Its distinctive features are (1) its ability to reproduce precisely the operating conditions and (2) its ability to measure the temperature field on the heat exchanger surface with an Infra Red camera for detecting in real time the evolution of the fooling deposit based on its thermal resistance. Numerical codes are used in conjunction with this experimental setup to determine the evolution of the fouling thickness from its thermal resistance.

Gaborieau, Cécile; Sommier, Alain; Toutain, Jean; Anguy, Yannick; Crepeau, Gérald; Gobin, Benoît

2012-04-01

142

Wind tunnel simulation of exhaust recirculation in an air-cooling system at a large power plant  

Microsoft Academic Search

The recirculation of hot exhaust air and its dependence on wind direction was investigated as a cause of reduced efficiency in an air-cooled condenser (ACC). A method of simulating exhaust air recirculation at an ACC platform using a wind tunnel is presented, and applied to a proposed ACC addition at an existing power plant. It was found that wind speed

Zhifu Gu; Xuerei Chen; William Lubitz; Yan Li; Wenlin Luo

2007-01-01

143

SET UP AND OPERATION OF A RECIRCULATING WETTED RIGID MEDIA EVAPORATIVE COOLER INSTALLED IN A GAS TURBINE COMBUSTION INLET AIR SYSTEM  

Microsoft Academic Search

A procedure for setting up and operating a recirculating evaporative cooler installed in the combustion air inlet system of a gas turbine is described. The procedure includes a recommendation for selecting the ambient operating wet and dry bulb temperatures. A description of the parameters used in the procedure and calculation methods are shown. In response to frequent inquiries about the

R. S. Johnson

144

Design of three recirculating-linac SRF systems for a 4-TeV mu(sup +)-mu(sup -) collider.  

National Technical Information Service (NTIS)

In a conceptual design of the accelerating systems for a 4-TeV mu(sup +)-mu(sup -) collider, three recirculating superconducting linacs (with energies reaching 70 GeV (with 350 MHz SRF), 250 GeV (800 MHz), and 2,000 GeV (1,300 GHz), respectively) are used...

Q. S. Shu D. Neuffer S. Simrock

1997-01-01

145

40 CFR 1065.127 - Exhaust gas recirculation.  

Code of Federal Regulations, 2013 CFR

...Exhaust gas recirculation. Use the exhaust gas recirculation (EGR) system installed with the engine or one that represents a typical in-use configuration. This includes any applicable EGR cooling...

2013-07-01

146

Comparative performance of CO2 measuring methods: marine aquaculture recirculation system application  

USGS Publications Warehouse

Many methods are available for the measurement of dissolved carbon dioxide in an aqueous environment. Standard titration is the typical field method for measuring dissolved CO2 in aquaculture systems. However, titrimetric determination of dissolved CO2 in marine water aquaculture systems is unsuitable because of the high dissolved solids, silicates, and other dissolved minerals that interfere with the determination. Other methods used to measure dissolved carbon dioxide in an aquaculture water included use of a wetted CO2 probe analyzer, standard nomographic methods, and calculation by direct measurements of the water's pH, temperature, and alkalinity. The determination of dissolved CO2 in saltwater based on partial pressure measurements and non-dispersive infra-red (NDIR) techniques with a CO2 gas analyzer are widely employed for oceanic surveys of surface ocean CO2 flux and are similar to the techniques employed with the head space unit (HSU) in this study. Dissolved carbon dioxide (DC) determination with the HSU using a infra-red gas analyzer (IRGA) was compared with titrimetric, nomographic, calculated, and probe measurements of CO2 in freshwater and in saltwater with a salinity ranging from 5.0 to 30 ppt, and a CO2 range from 8 to 50 mg/L. Differences in CO2 measurements between duplicate HSUs (0.1–0.2 mg/L) were not statistically significant different. The coefficient of variation for the HSU readings averaged 1.85% which was better than the CO2 probe (4.09%) and that for the titrimetric method (5.84%). In all low, medium and high salinity level trials HSU precision was good, averaging 3.39%. Differences existed between comparison testing of the CO2 probe and HSU measurements with the CO2 probe readings, on average, providing DC estimates that were higher than HSU estimates. Differences between HSU and titration based estimates of DC increased with salinity and reached a maximum at 32.2 ppt. These differences were statistically significant (P < 0.05) at all salinity levels greater than 0.3 ppt. Results indicated reliable replicated results from the head space unit with varying salinity and dissolved carbon dioxide concentrations.

Pfeiffer, T. J.; Summerfelt, S. T.; Watten, B. J.

2011-01-01

147

Design of Three Re-Circulating Superconducting RF Accelerating Systems for a 4-TeV Muon Collider  

NASA Astrophysics Data System (ADS)

Muon collliders can provide strong potential advantages in high energy physics and are an attractive alternative to e^-e^+ colliders due to the small synchrotron losses. The design of the accelerating systems for muon however is technically very challenging since very rapidly increasing in muon energies is required due to the short life time of 2.2 x 10-6 s at rest. In a conceptual design of the accelerating system, three re-circulating Linacs (with energies reaching 70 GeV (with 350-MHz SRF, 10-MV/m), 250 GeV (800-MHz, 20-MV/m) and 2000 GeV (1300-GHz, 25-MV/m), respectively) are chosen. The cryogenic systems must provide 2-K superfluid LHe to the SRF 1300-GHz Linac and 4-K normal LHe to the 350-MHz and 800-MHz Linacs. We present the basic design concepts of the superconducting RF cavities, input and HOM couplers, the RF high power klystrons, low level RF control and its associated cryogenic system in a 4-TeV muon collider.

Shu, Q.-S.; Neuffer, D.; Simrock, S.

1997-05-01

148

Recirculation as a possible microbial control strategy in the production of marine larvae  

Microsoft Academic Search

Marine hatcheries represent high value, low waste systems for larvae that are sensitive to general infections by opportunistic bacteria. In intensive cultivation several procedures destabilise the microbial community of the rearing water and favour growth of potentially harmful microbes. Recirculation aquaculture systems (RASs) have properties that may contribute to microbial stabilisation, including long water retention time and a large surface

Kari J. K. Attramadal; Ingrid Salvesen; Renyu Xue; Gunvor Øie; Trond R. Størseth; Olav Vadstein; Yngvar Olsen

149

Recirculation System for Geothermal Energy Recovery in Sedimentary Formations: Laboratory Experiments and Numerical Simulations  

NASA Astrophysics Data System (ADS)

Geothermal energy resources are more widespread than previously thought and have the potential for providing a significant amount of sustainable clean energy worldwide. In particular, hot permeable sedimentary formations provide many advantages over traditional geothermal recovery and enhanced geothermal systems in low permeability crystalline formations. These include: (1) eliminating the need for hydraulic fracturing, (2) significant reduction in risk for induced seismicity, (3) reducing the need for surface wastewater disposal, (4) contributing to decreases in greenhouse gases, and (5) potential use for CO2 sequestration. Advances in horizontal drilling, completion, and production technology from the oil and gas industry can now be applied to unlock these geothermal resources. Here, we present experimental results from a laboratory scale circulation system and numerical simulations aimed at quantifying the heat transfer capacity of sedimentary rocks. Our experiments consist of fluid flow through a saturated and pressurized sedimentary disc of 23-cm diameter and 3.8-cm thickness heated along its circumference at a constant temperature. Injection and production ports are 7.6-cm apart in the center of the disc. We used DI de-aired water and mineral oil as working fluids and explored temperatures from 20 to 150 oC and flow rates from 2 to 30 ml/min. We performed experiments on sandstone samples (Castlegate and Kirby) with different porosity, permeability and thermal conductivity to evaluate the effect of hydraulic and thermal properties on the heat transfer capacity of sediments. The producing fluid temperature followed an exponential form with time scale transients between 15 and 45 min. Steady state outflow temperatures varied between 60% and 95% of the set boundary temperature, higher percentages were observed for lower temperatures and flow rates. We used the flow and heat transport simulator TOUGH2 to develop a numerical model of our laboratory setting. Given the remarkable match between our observations and numerical results, we extended our model to explore a wider range of thermal and hydrological parameters beyond the experimental conditions. Our results prove the capability of heat transfer in sedimentary formations for geothermal energy production.) Sandstone sample with two thermally insulating Teflon caps (white discs). In and out arrows indicate the flow direction while the sample is heated along its circumference (heater not shown). B) Example of a 2D temperature distribution during injection. White x shows the location of the flow ports, inlet (left) and outlet (right). Red is the set boundary temperature and blue is the fluid temperature at the inlet.

Elkhoury, J. E.; Detwiler, R. L.; Serajian, V.; Bruno, M. S.

2012-12-01

150

Water Systems  

NSDL National Science Digital Library

Water cycle concepts and basics including the distribution of water on the planet in oceans, rivers and lakes, glaciers and atmosphere. Defines basic terms: states of water, evaporation, transpiration, condensation, precipitation, melting. Good illustrations, maps and photos. Excellent list itemizes human uses and impacts on water and the water cycle. Links to more detailed references are provided, case studies illustrate current concerns and issues in Ontario, Canada.

151

The trapping system for the recirculated gases at different locations of the exhaust gas recirculation (EGR) pipe of a homogeneous charge compression ignition (HCCI) engine  

NASA Astrophysics Data System (ADS)

Nowadays, in diesel engines, it is typical to recycle exhaust gases (EGR) in order to decrease pollutant emissions. However, few studies report the precisely measured composition of the recycled gases. Indeed, in order to know precisely the composition of the EGR gases, they have to be sampled hot and not diluted, in contrast to the usual practice. Thus, a new system to collect such samples was developed. With this new trapping system, it is possible to measure the concentrations of NOx, CO, CO2, O2, hydrocarbons (HCs) in the range C1-C9, aldehydes, ketones and PAHs. The trapping system and the analytical protocol used are described in this paper.

Piperel, A.; Montagne, X.; Dagaut, P.

2008-10-01

152

A VUV gas transmission monitor and recirculating gas system for the PHENIX hadron blind detector  

Microsoft Academic Search

The PHENIX Hadron Blind Detector (HBD) is a high performance Cherenkov counter that uses pure CF4 to detect electrons in relativistic heavy ion collisions at RHIC. It requires extremely high purity gas in order to achieve a high photoelectron yield, preserve the quality of its cesium iodide photocathodes, and maintain stable gas gain in its GEM detectors. In particular, water

B. Azmoun; R. P. Pisani; S. Stoll; C. Woody

2007-01-01

153

Acute fulminant hepatitis B in a patient with diabetic nephropathy treated successfully with concomitant lamivudine and molecular adsorbents recirculating system.  

PubMed

A 36-year-old man with type 2 diabetes and diabetic nephropathy treated with hemodialysis developed hepatitis B virus (HBV)-induced acute fulminant hepatic failure (FHF). Despite supportive treatment, the condition rapidly progressed as manifested by severe jaundice, coagulopathy and hepatic coma. He was placed on the waiting list for liver transplantation and was treated with lamivudine and extracoporeal liver support with the molecular adsorbent recirculating system (MARS). After three 8-h sessions of MARS treatment in 1 week, he had remarkable improvement in clinical symptoms and serum biochemistry. On the 14th hospital day, surface antigen seroconversion was noted with undetectable hepatitis B virus surface antigen (HBs Ag) and low titre of anti-HBs antibody, indicating a complete recovery from acute fulminant hepatitis B. MARS treatment has been reported to benefit patients with liver failure from different causes including acute exacerbation of chronic hepatitis B, poisoning, post transplantation and Wilson's disease. The present case suggests its potential benefit when combined with lamivudine in treating uremic patients with acute fulminant hepatitis B. PMID:16269182

Tsai, Shih-Hung; Chang, Hao-Ming; Hsieh, Chung-Bao; Chao, You-Chen; Hsieh, Tsai-Yuan

2006-07-01

154

Potentials and limitations of biomethane and phosphorus recovery from sludges of brackish/marine aquaculture recirculation systems: a review.  

PubMed

Brackish/marine recirculation aquaculture systems (RAS) produce a relatively small but concentrated waste stream. The produced waste is perceived as a constraint for sustainable development of brackish/marine RAS. Appropriate disposal of sludge or waste from brackish/marine RAS is of great importance for widespread acceptance and implementation. Anaerobic stabilization of RAS sludge is considered as a potential cost-effective methodology to achieve effective sludge reduction and biogas production. Therefore, this review presents an overview of studies conducted on anaerobic digestion of sludge from brackish/marine RAS. Several researchers have shown that specific methane yield (SMY) of anaerobic digestion of sludges from brackish/marine RAS is relatively low, mainly in the range of 0.001-0.184 m(3) CH4 (STP)/kg COD of sludge added. The possible reasons for low SMY are reviewed in this work and can be mainly attributed to applied experimental set-ups, particularly improper inoculum, and high salinity, mainly resulting from high sodium cation levels. This review also evaluates the potentials and limitations for phosphorus recovery from the waste streams. Additionally, corresponding approaches to enhance specific methanogenic activities are proposed, particularly about the need for further thickening sludges from brackish/marine RAS in order to increase SMY from the wastes and downsize the anaerobic digestion units. PMID:24140486

Zhang, Xuedong; Spanjers, Henri; van Lier, Jules B

2013-12-15

155

Development of zooplankton culture subsystem for a closed ecological recirculating aquaculture system (CERAS)  

NASA Astrophysics Data System (ADS)

Ten parthenogenetic females of Moina macrocopa were placed in small cells with different flow conditions. The cells were opened after three-days of cultivation, and the water fleas in each cell were counted. It appeared that M. macrocopa were cultured effectively in a relatively slow current, 10 cm/min., but the population growth was not significantly influenced by the difference in flow direction. Subsequent, filtration efficiencies of filters with various pore sizes were compared. Four available porous hollow-fiber membrane modules, ACP-1010, AHP-1010, PSP-103, and PMP-102 (Asahi-Kasei Corp.), were tested. The module with the larger pore size initially filtered a greater amount of water but clogged up sooner. ACP-1010, which has the smallest pores, was considered to be suitable to filter condensed algal water due to its durability and stable filtration. An improved zooplankton culture device (IZCD) was designed and constructed based on these examinations. IZCD is a 13.2L airtight device characterized by a short and thick rearing tank and alternate filtration with paired fine hollow-fiber membrane modules. It must be tested and revised to be used in research into the optimal conditions for a zooplankton culture in a closed environment.

Omori, Katsunori; Oguchi, Mitsuo; Takeuchi, Toshio

2006-01-01

156

Performance of the seaweeds Gracilaria salicornia and Caulerpa lentillifera as biofilters in a hatchery scale recirculating aquaculture system for juvenile spotted babylons ( Babylonia areolata )  

Microsoft Academic Search

This study was conducted to determine the feasibility of using seaweeds as biofilters in a hatchery scale recirculating aquaculture\\u000a system for juvenile spotted babylons (Babylonia areolata). Two seaweeds Gracilaria salicornia and Caulerpa lentillifera were used with three initial biomass levels of each species (280, 560 and 840 g wet weight m?3). Spotted babylon with an average initial shell length of 1.32 ± 0.01 cm and body weight

Nilnaj Chaitanawisuti; Wannanee Santhaweesuk; Sirusa Kritsanapuntu

157

Recirculating rotary gas compressor  

DOEpatents

A positive displacement, recirculating Roots-type rotary gas compressor which operates on the basis of flow work compression. The compressor includes a pair of large diameter recirculation conduits (24 and 26) which return compressed discharge gas to the compressor housing (14), where it is mixed with low pressure inlet gas, thereby minimizing adiabatic heating of the gas. The compressor includes a pair of involutely lobed impellers (10 and 12) and an associated port configuration which together result in uninterrupted flow of recirculation gas. The large diameter recirculation conduits equalize gas flow velocities within the compressor and minimize gas flow losses. The compressor is particularly suited to applications requiring sustained operation at higher gas compression ratios than have previously been feasible with rotary pumps, and is particularly applicable to refrigeration or other applications requiring condensation of a vapor.

Weinbrecht, John F. (601 Oakwood Loop, NE., Albuquerque, NM 87123)

1992-01-01

158

Recirculating rotary gas compressor  

DOEpatents

A positive displacement, recirculating Roots-type rotary gas compressor is described which operates on the basis of flow work compression. The compressor includes a pair of large diameter recirculation conduits which return compressed discharge gas to the compressor housing, where it is mixed with low pressure inlet gas, thereby minimizing adiabatic heating of the gas. The compressor includes a pair of involutely lobed impellers and an associated port configuration which together result in uninterrupted flow of recirculation gas. The large diameter recirculation conduits equalize gas flow velocities within the compressor and minimize gas flow losses. The compressor is particularly suited to applications requiring sustained operation at higher gas compression ratios than have previously been feasible with rotary pumps, and is particularly applicable to refrigeration or other applications requiring condensation of a vapor. 12 figs.

Weinbrecht, J.F.

1992-02-25

159

Electron recirculation in electrostatic multicusp systems: 1. Confinement and losses in simple power law wells  

Microsoft Academic Search

A large body of work over the past 35 years has been devoted to the study of cusp confinement of electrons, ions, and plasmas. Nearly all of this has examined single particle electron (or ion) motion or the motion of particles in neutral plasmas within cusped magnetic systems, generally without internal electric potential fields. In this note the problem of

R. W. Bussard; K. E. King

1991-01-01

160

Systems and methods for reactive distillation with recirculation of light components  

DOEpatents

Systems and methods for producing gas-to-liquids products using reactive distillation are provided. The method for producing gas-to-liquids products can include reacting a feedstock in a column having a distillation zone and a reaction zone to provide a bottoms stream and an overhead stream. A first portion of the overhead stream can be recycled to the column at the top of the reaction zone and second portion of the overhead stream can be recycled to the column at the bottom of the reaction zone.

Stickney, Michael J. (Nassau Bay, TX) [Nassau Bay, TX; Jones, Jr., Edward M. (Friendswood, TX)

2011-07-26

161

Electron recirculation in electrostatic multicusp systems: 1. Confinement and losses in simple power law wells  

SciTech Connect

A large body of work over the past 35 years has been devoted to the study of cusp confinement of electrons, ions, and plasmas. Nearly all of this has examined single particle electron (or ion) motion or the motion of particles in neutral plasmas within cusped magnetic systems, generally without internal electric potential fields. In this note the problem of electron motion, confinement and losses is analyzed in the non-LTE, electron-rich plasma system with anisotropic radial energy in both species, in multicusp Polywell geometry. The bulk problem is treated as one-dimensional, with arbitrary spatial indices of radial B and E field variation. Bulk diamagnetic collective effects are modelled as they influence this 1-D spatial variation of B field, but electron entry into single cusp volumes includes elements of the geometric effects of the real 3-D configuration. Electron motions in mirror reflection regions are analyzed on the usual basis of conservation of magnetic moment of the electron at entry into the confining cusp. However, turning points of this motion are modified to account for the effects of diamagnetic currents on this process. Comparison with non-Polywell models is made where useful and appropriate. Further details are given in the following sections.

Bussard, R.W.; King, K.E.

1991-04-19

162

Mechanical mode floating medium filters for recirculating systems in aquaculture for higher solids retention and lower freshwater usage.  

PubMed

The aim of this work was to develop a better understanding of a floating medium in a mechanical filtration mode. The experiments were carried out using a commonly available polystyrene floating medium filter with the grain size of 1mm. A sand medium filter with the similar grain size was also tested for the comparison. A short-term trial of 2h and a long-term of 20 days filtration times were conducted with three custom manufactured pressurized filters of 16l. The filters were operated under three different configurations: (i) upflow with floating media (UFMF), (ii) downflow with floating media (DFMF) and (iii) downflow with a sand medium (DSF). The results of the long-term trial indicated that at a flow rate of 22 m/h, the UFMF and DSF had similar solid removal capacity with an average total suspended solids (TSS) removal efficiency of 60%. The DFMF could only remove 33% of TSS. However, during the short-term trial, TSS removal efficiency of the UFMF was better compared to the DSF (e.g., 71%, 56% and 57% of TSS removal in UFMF compared to 66%, 49% and 41% in the DSFF at the flow rates of 20, 25 and 31m/h, respectively). The energy requirements of each filter were compared by measuring the pressure differential across each filter. The long-term trial indicated that the UFMF had a significantly less pressure differential (44 kPa) compared to the DSF (80 kPa) (p<0.001). This was further confirmed that at different flow rates whereby the DSF displayed higher pressure differentials for filtration rates at 350, 450, 550 and 800 l/h. The study indicated that floating medium filter was better and more applicable to recirculating aquaculture systems than conventional pressurized sand filter. PMID:17532213

Steicke, C; Jegatheesan, V; Zeng, C

2007-12-01

163

Exhaust gas recirculation system  

SciTech Connect

An EGR assembly is disclosed of a sonic flow EGR valve and a fluid pressure actuated servo operated by air pressure modified by an air bleed device controlled in response to changes in carburetor venturi vacuum levels to provide EGR valve openings in proportion to engine air flow increases.

Rachedi, S.H.

1983-08-16

164

Exhaust gas recirculation system  

SciTech Connect

There is disclosed an EGR assembly of a sonic flow EGR valve and a fluid pressure actuated servo operated by air pressure modified by an air bleed device controlled in response to changes in carburetor venturi vacuum levels to provide EGR valve openings in proportion to engine air flow increases.

Rachedi, S.H.

1983-10-18

165

Containment system for supercritical water oxidation reactor  

DOEpatents

A system for containment of a supercritical water oxidation reactor in the event of a rupture of the reactor. The system includes a containment for housing the reaction vessel and a communicating chamber for holding a volume of coolant, such as water. The coolant is recirculated and sprayed to entrain and cool any reactants that might have escaped from the reaction vessel. Baffles at the entrance to the chamber prevent the sprayed coolant from contacting the reaction vessel. An impact-absorbing layer is positioned between the vessel and the containment to at least partially absorb momentum of any fragments propelled by the rupturing vessel. Remote, quick-disconnecting fittings exterior to the containment, in cooperation with shut-off valves, enable the vessel to be isolated and the system safely taken off-line. Normally-closed orifices throughout the containment and chamber enable decontamination of interior surfaces when necessary.

Chastagner, Philippe (3134 Natalie Cir., Augusta, GA 30909-2748)

1994-01-01

166

Residential hot water distribution systems: Roundtablesession  

SciTech Connect

Residential building practice currently ignores the lossesof energy and water caused by the poor design of hot water systems. Theselosses include: combustion and standby losses from water heaters, thewaste of water (and energy) while waiting for hot water to get to thepoint of use; the wasted heat as water cools down in the distributionsystem after a draw; heat losses from recirculation systems and thediscarded warmth of waste water as it runs down the drain. Severaltechnologies are available that save energy (and water) by reducing theselosses or by passively recovering heat from wastewater streams and othersources. Energy savings from some individual technologies are reported tobe as much as 30 percent. Savings calculations of prototype systemsincluding bundles of technologies have been reported above 50 percent.This roundtable session will describe the current practices, summarizethe results of past and ongoing studies, discuss ways to think about hotwater system efficiency, and point to areas of future study. We will alsorecommend further steps to reduce unnecessary losses from hot waterdistribution systems.

Lutz, James D.; Klein, Gary; Springer, David; Howard, Bion D.

2002-08-01

167

A Mathematical Model of Solute Coupled Water Transport in Toad Intestine Incorporating Recirculation of the Actively Transported Solute  

Microsoft Academic Search

A mathematical model of an absorbing leaky epithelium is developed for analysis of solute coupled wa- ter transport. The non-charged driving solute diffuses into cells and is pumped from cells into the lateral intercellular space ( lis ). All membranes contain water channels with the solute passing those of tight junction and interspace base- ment membrane by convection-diffusion. With solute

Erik Hviid Larsen; Jakob Balslev Sørensen; Jens Nørkær Sørensen

2000-01-01

168

Biodiversity of N-cycle bacteria in nitrogen removing moving bed biofilters for freshwater recirculating aquaculture systems  

Microsoft Academic Search

Maintenance of optimal water quality and removal of nitrogen compounds pose challenges to aquaculture worldwide. Presence and activity of different bacteria involved in nitrogen cycling in the biofilm of a moving bed biofilm reactor (MBBR) connected to a Koi carp tank were investigated experimentally. For this MBBR system, a nitrogen removing rate of 3.5g nitrogen per day was found in

Maartje A. H. J. van Kessel; Harry R. Harhangi; Katinka van de Pas-Schoonen; J. L. C. M. van de Vossenberg; Gert Flik; Mike S. M. Jetten; Peter H. M. Klaren

2010-01-01

169

Effect of Water pH on Yield and Nutritional Status of Greenhouse Cucumber Grown in Recirculating Hydroponics  

Microsoft Academic Search

Cucumbers are produced in integrated hydroponic and aquaculture systems (aquaponics). Aquaponics balances pH for plants, fish, and nitrifying bacteria. Nitrification prevents buildup of toxic waste ammonia by conversion to nitrate (NO3 - nitrogen (N). The pH for hydroponic cucumbers (5.5–6.0) and nitrification (7.5–9.0) requires reconciliation to improve systems integration. Cucumbers were grown at pH of 5.0, 6.0, 7.0, and 8.0

R. V. Tyson; E. H. Simonne; D. D. Treadwell; M. Davis; J. M. White

2008-01-01

170

Wash water recovery system  

NASA Technical Reports Server (NTRS)

The Wash Water Recovery System (WWRS) is intended for use in processing shower bath water onboard a spacecraft. The WWRS utilizes flash evaporation, vapor compression, and pyrolytic reaction to process the wash water to allow recovery of potable water. Wash water flashing and foaming characteristics, are evaluated physical properties, of concentrated wash water are determined, and a long term feasibility study on the system is performed. In addition, a computer analysis of the system and a detail design of a 10 lb/hr vortex-type water vapor compressor were completed. The computer analysis also sized remaining system components on the basis of the new vortex compressor design.

Deckman, G.; Rousseau, J. (editor)

1973-01-01

171

Geothermal hot water system  

SciTech Connect

Geothermal hot water system including a hot water tank and a warm water tank which are heated independently of each other by a close loop freon system. The closed loop freon system includes a main condenser which heats water for the warm water tank and a super-heated condenser which heats water for the hot water tank, and where the freon passes through a water evaporator which is heated by water such as from a well or other suitable source. The water evaporator in the closed loop freon system passes the water through but no environmental change to the water. An electrical circuit including aquastats in the warm water tank connected therethrough controls operation of the closed loop freon system including respective pumps on the super-heated condenser and main condenser for pumping water. Pumps pump water through the main condenser for the warm tank and through the super-heated condenser for the hot tank. The system provides for energy conservation in that the head pressure of the compressor is kept in the lower operating ranges as determined by the discharge flow of the main condenser which varies by the head pressure and temperature flow control which varies by temperature. The geothermal hot water system uses a least amount of energy in heating the water in the hot tank as well as the warm tank.

Dittell, E.W.

1983-05-10

172

Household hot water systems  

Microsoft Academic Search

An arrangement for combination with the conventional hot water system of a house or building in which the water is conventionally heated and stored in a tank, the arrangement comprising a solar energy panel (at an upper level) with a thermostatic valve and a supplementary cold water tank, connected into the system in such a way that hot water is

Tacchi

1983-01-01

173

Effect of hydraulic loading rate on the efficiency of effluent treatment in a recirculating puffer aquaculture system coupled with constructed wetlands  

NASA Astrophysics Data System (ADS)

Constructed wetlands (CWs) were integrated into an indoor recirculating aquaculture system of obscure puffer (Takifugu obscurus) for effluent treatment. The effect of hydraulic loading rate (HLR) on the efficiency of effluent treatment by CWs was examined for over a month. The CWs were operated under brackish conditions (salinity 7.4-7.6) at 3 different HLRs (0.762, 0.633, and 0.458 m d-1) 3 times, 10 days each. Overall, the CWs exhibited high efficiency in removal of total ammonium nitrogen (by 81.03-92.81%) and nitrite nitrogen (by 99.40%-99.68%). The efficiency of CWs in removal of total ammonium nitrogen, nitrate nitrogen, total Kjeldahl nitrogen, total phosphorous, and total suspended solids (TSS) increased with the decrease of HLR. The CWs operated at the 3 HLRs in a decreasing trend proves to be effective, providing a useful method for effluent treatment in commercial puffer aquaculture systems.

Xu, Jiabo; Shi, Yonghai; Zhang, Genyu; Liu, Jianzhong; Zhu, Yazhu

2013-11-01

174

Amorphous Silica Scale in Cooling Waters.  

National Technical Information Service (NTIS)

In 1968, most of the evaporation cooled recirculating water systems at Los Alamos Scientific Laboratory were nearly inoperable due to scale. These systems, consisting of cooling towers, evaporative water coolers, evaporative condensers, and air washers ha...

W. S. Midkiff H. P. Foyt

1976-01-01

175

Intermediate water recovery system  

NASA Technical Reports Server (NTRS)

A water recovery system for collecting, storing, and processing urine, wash water, and humidity condensates from a crew of three aboard a spacecraft is described. The results of a 30-day test performed on a breadboard system are presented. The intermediate water recovery system produced clear, sterile, water with a 96.4 percent recovery rate from the processed urine. Recommendations for improving the system are included.

Deckman, G.; Anderson, A. R. (editor)

1973-01-01

176

Evaluation of the effects of water agitation by air injection and water recirculation on the heat transfer coefficients in immersion cooling  

Microsoft Academic Search

Most industrial food cooling is performed by air blast, water spraying and immersion cooling. Immersion cooling is simple, with low operational cost and leads to food quick cooling. The objective of this work was to investigate the influence of water agitation method (water injection, air injection and water injection coupled to a Venturi ejector) on the average heat transfer coefficient

J. B. Laurindo; B. A. M. Carciofi; R. R. Silva; C. E. Dannenhauer; H. Hense

2010-01-01

177

Exhaust gas recirculator  

SciTech Connect

An exhaust gas recirculator for an internal combustion engine having an exhaust pipe, an intake manifold and a carburetor throttle valve. The exhaust gas recirculator comprises an egr passage which makes the exhaust pipe communicate with the intake manifold, an egr controlling valve and an egr valve respectively arranged in the upper and lower portions of the egr passage. The egr valve operates in association with the carburetor throttle valve for metering the flow of egr gas. The egr controlling valve is separated by a diaphragm into an egr gas chamber communicating with the egr passage between the egr controlling valve and the egr valve and a negative pressure chamber communicating with the intake manifold. The negative pressure chamber contains a compression spring, and the diaphragm is connected with a valve member through a rod upon which is disposed a stopper to serve as a different seal in place of the valve member to close off the exhaust gas passage, which valve member and stopper are constructed to be opened and closed by pressure difference between the egr gas chamber and the negative pressure chamber and by elastic force of the compression spring. The egr controlling valve functions to control the pressure difference around the egr valve to be constant.

Suda, K.

1983-01-04

178

The Role of Water Chemistry in Marine Aquarium Design: A Model System for a General Chemistry Class  

ERIC Educational Resources Information Center

Water chemistry is central to aquarium design, and it provides many potential applications for discussion in undergraduate chemistry and engineering courses. Marine aquaria and their life support systems feature many chemical processes. A life support system consists of the entire recirculation system, as well as the habitat tank and all ancillary…

Keaffaber, Jeffrey J.; Palma, Ramiro; Williams, Kathryn R.

2008-01-01

179

Hot water heating system  

Microsoft Academic Search

A solar hot water heating system has a primary tank heated by solar energy utilizing a heat transfer medium circulated between a solar collector and a heat exchanger located in the primary tank. Usually a back-up tank is provided to supplement the solar system. The primary tank receives cold water from a pressurized source. Its hot water outlet is connected

1984-01-01

180

Water turbine generator system  

Microsoft Academic Search

A water turbine generator system for use in a stream or river, said system having a catch basin formed by an end wall, a plurality of water chutes downstream of the catch basin and in communication with the catch basin by gates and closures and a plurality of turbines and associated generators journalled in the chutes for rotation by water

Brankovics

1982-01-01

181

Closeout of IE Compliance Bulletin 86-03: Potential failure of multiple ECCS (Emergency Core Cooling System) pumps due to single failure of air-operated valve in minimum flow recirculation line  

Microsoft Academic Search

Documentation is provided in this report for the closeout of IE Compliance Bulletin 86-03 regarding the potential failure of multiple Emergency Core Cooling System (ECCS) pumps due to a single failure of an air-operated valve in a minimum flow recirculation line. Closeout is based on the implementation and verification of four actions required by the bulletin. Evaluation of utility responses

W. J. Foley; R. S. Dean; A. Hennick

1990-01-01

182

Mineral nutrient concentration and uptake by tomato irrigated with recirculating aquaculture water as influenced by quantity of fish waste products supplied  

Microsoft Academic Search

Fish and tomato (Lycopersicon esculentum Mill.) production were linked in a recirculaing water system. Fish (tilapia) were fed a commercial diet with 32% protein. Tomato cultivars ‘Laura’ and ‘Kewalo’ were grown during summer 1988 and spring 1989, respectively, in a Raleigh, NC greenhouse. Plants were grown in biofilters at 4 plants\\/m and surface irrigated 8 times daily with water pumped

M. R. McMurtry; D. C. Sanders; P. V. Nelson; A. Nash

1993-01-01

183

Recirculation-aeration: Bibliography for aquaculture. Bibliographies and literature of agriculture (Final)  

SciTech Connect

The bibliography includes literature citations through 1992 related to water recirculation and aeration in aquaculture. The focus is on filtration, aeration, and circulation techniques in various aquaculture situations.

Perschbacher, P.W.; Powell, R.V.; Freeman, D.W.; Lorio, W.J.; Hanfman, D.T.

1993-08-01

184

Solar water heating system  

Microsoft Academic Search

A solar water heating system is described in which piping arrangements and solenoid operated valves are combined with a water storage heater and solar heater or collectors in a manner to protect the system against over temperature and against freezing without the use of antifreeze or auxiliary heat exchanger systems.

Cook

1978-01-01

185

Cooling Water Systems Module  

NSDL National Science Digital Library

The Center for the Advancement of Process Technology presents this free sample module on cooling water systems in the process industry. The material includes 21 slides and will help learners understand related terms, the purpose of the basic equipment involved in cooling water systems and the safety, health and environmental concerns involved with these systems.

2013-01-04

186

Options for transpiration water removal in a crop growth system under zero gravity conditions  

NASA Technical Reports Server (NTRS)

The operation of a microgravity crop-growth system is a critical feature of NASA's Closed Ecological Life Support System (CELSS) development program. Transpiration-evolved water must be removed from the air that is recirculated in such a system, perhaps supplying potable water in the process. The present consideration of candidate systems for CELSS water removal gives attention to energy considerations and to a mechanical, inertial-operation water-separation system that was chosen due to the depth of current understanding of its operation.

Blackwell, C. C.; Kliss, M.; Yendler, B.; Borchers, B.; Yendler, Boris S.; Nguyen, Thoi K.; Waleh, Ahmad

1991-01-01

187

Water Purification Systems  

NASA Technical Reports Server (NTRS)

A water purification/recycling system developed by Photo-Catalytics, Inc. (PCI) for NASA is commercially available. The system cleanses and recycles water, using a "photo-catalysis" process in which light or radiant energy sparks a chemical reaction. Chemically stable semiconductor powders are added to organically polluted water. The powder absorbs ultraviolet light, and pollutants are oxidized and converted to carbon dioxide. Potential markets for the system include research and pharmaceutical manufacturing applications, as well as microchip manufacture and wastewater cleansing.

1992-01-01

188

Airlift recirculation well test results -- Southern sector  

SciTech Connect

Chlorinated solvents used in the A and M-Areas at the Savannah River Site (SRS) from 1952--1982 have contaminated the groundwater under the site. A plume of groundwater contaminated with trichloroethylene (TCE) and perchloroethylene (PCE) in the Lost Lake aquifer is moving generally southward with the natural flow of groundwater. To comply with the requirements of the current SCDHEC Part B Permit, a series of wells is being installed to contain and treat the plume. Airlift Recirculation Wells (ARW) are a new and innovative technology with potential for more cost effective implementation than conventional pump and treat systems. Two Airlift Recirculation Wells have been installed and tested to quantify performance parameters needed to locate a line of these wells along the leading edge of the contaminant plume. The wells proved to be very sensitive to proper development, but after this requirement was met, performance was very good. The Zone of Capture has been estimated to be within a radius of 130--160 ft. around the wells. Thus a line of wells spaced at 250 ft. intervals could intercept the contaminant plume. At SSR-012, TCE was stripped from the groundwater at approximately 1.2 lb./day. The longer term effect of the recirculation wells upon the plume and the degree of recirculation within the aquifer itself will require additional data over a longer time period for an accurate review. Data collection is ongoing.

White, R.M.; Hiergesell, R.A.

1997-08-01

189

SELECTED METABOLIC ASPECTS OF PIKEPERCH, STIZOSTEDION LUCIOPERCA (L.) REARED IN A WATER RECIRCULATION SYSTEM  

Microsoft Academic Search

The aim of the present study was to evaluate the effect of fish size (BW 11.7 g in the PS group, and 28.1 g in the PL group), feeding (SDA effect), and starvation (4, 13, 19 or 26 days in the PS-S group, and 4 or 13 days in the PL-S group) on oxygen consumption (OC ,m g O2 kg

Krystyna Demska-Zakêœ; Piotr Karczewski; Andrzej Karpiñski

190

Reactor water cleanup system  

DOEpatents

A reactor water cleanup system includes a reactor pressure vessel containing a reactor core submerged in reactor water. First and second parallel cleanup trains are provided for extracting portions of the reactor water from the pressure vessel, cleaning the extracted water, and returning the cleaned water to the pressure vessel. Each of the cleanup trains includes a heat exchanger for cooling the reactor water, and a cleaner for cleaning the cooled reactor water. A return line is disposed between the cleaner and the pressure vessel for channeling the cleaned water thereto in a first mode of operation. A portion of the cooled water is bypassed around the cleaner during a second mode of operation and returned through the pressure vessel for shutdown cooling.

Gluntz, Douglas M. (San Jose, CA); Taft, William E. (Los Gatos, CA)

1994-01-01

191

Reactor water cleanup system  

DOEpatents

A reactor water cleanup system includes a reactor pressure vessel containing a reactor core submerged in reactor water. First and second parallel cleanup trains are provided for extracting portions of the reactor water from the pressure vessel, cleaning the extracted water, and returning the cleaned water to the pressure vessel. Each of the cleanup trains includes a heat exchanger for cooling the reactor water, and a cleaner for cleaning the cooled reactor water. A return line is disposed between the cleaner and the pressure vessel for channeling the cleaned water thereto in a first mode of operation. A portion of the cooled water is bypassed around the cleaner during a second mode of operation and returned through the pressure vessel for shutdown cooling. 1 figure.

Gluntz, D.M.; Taft, W.E.

1994-12-20

192

Purge water management system  

DOEpatents

A purge water management system is described for effectively eliminating the production of purge water when obtaining a groundwater sample from a monitoring well. In its preferred embodiment, the purge water management system comprises an expandable container, a transportation system, and a return system. The purge water management system is connected to a wellhead sampling configuration, typically permanently installed at the well site. A pump, positioned with the monitoring well, pumps groundwater through the transportation system into the expandable container, which expands in direct proportion with volume of groundwater introduced, usually three or four well volumes, yet prevents the groundwater from coming into contact with the oxygen in the air. After this quantity of groundwater has been removed from the well, a sample is taken from a sampling port, after which the groundwater in the expandable container can be returned to the monitoring well through the return system. The purge water management system prevents the purge water from coming in contact with the outside environment, especially oxygen, which might cause the constituents of the groundwater to oxidize. Therefore, by introducing the purge water back into the monitoring well, the necessity of dealing with the purge water as a hazardous waste under the Resource Conservation and Recovery Act is eliminated.

Cardoso-Neto, J.E.; Williams, D.W.

1995-01-01

193

Purge water management system  

DOEpatents

A purge water management system for effectively eliminating the production of purge water when obtaining a groundwater sample from a monitoring well. In its preferred embodiment, the purge water management system comprises an expandable container, a transportation system, and a return system. The purge water management system is connected to a wellhead sampling configuration, typically permanently installed at the well site. A pump, positioned with the monitoring well, pumps groundwater through the transportation system into the expandable container, which expands in direct proportion with volume of groundwater introduced, usually three or four well volumes, yet prevents the groundwater from coming into contact with the oxygen in the air. After this quantity of groundwater has been removed from the well, a sample is taken from a sampling port, after which the groundwater in the expandable container can be returned to the monitoring well through the return system. The purge water management system prevents the purge water from coming in contact with the outside environment, especially oxygen, which might cause the constituents of the groundwater to oxidize. Therefore, by introducing the purge water back into the monitoring well, the necessity of dealing with the purge water as a hazardous waste under the Resource Conservation and Recovery Act is eliminated.

Cardoso-Neto, Joao E. (North Augusta, SC); Williams, Daniel W. (Aiken, SC)

1996-01-01

194

Nitric Oxide Formation in Combustion Processes with Strong Recirculation.  

National Technical Information Service (NTIS)

The principal objective of the combustion experiments was to obtain information on the nitric oxide formation process in a continuous flow combustion system in which the flame is stabilized by recirculation. Specifically, the factors affecting nitric oxid...

C. T. Bowman L. S. Cohen M. N. Director

1973-01-01

195

Design study of a gas turbine combustor with heat recirculation  

NASA Technical Reports Server (NTRS)

A means of avoiding stoichiometric combustion, reducing emissions, and yet providing stable burning for lean mixtures is based on the use of heat recirculation rather than flow recirculation. This paper is concerned with the calculations of the design parameters of a gas turbine combustor with heat exchanger to produce the desired preheat temperature. The combustor inlet temperature, maximum temperature, equivalence ratio and recirculated heat are determined by thermodynamic analysis. The heat transfer analysis then provides the dimensions of the system to produce the predetermined boundary conditions. It is indicated that practical combustor design may be feasible for reactant mixtures as low as equivalence ratio 0.2.

Ganji, A.; Branch, M. C.; Oppenheim, A. K.

1976-01-01

196

Coke-free dry reforming of model diesel fuel by a pulsed spark plasma at low temperatures using an exhaust gas recirculation (EGR) system  

NASA Astrophysics Data System (ADS)

Dry reforming of diesel fuel, an endothermic reaction, is an attractive process for on-board hydrogen/syngas production to increase energy efficiency. For operating this dry reforming process in a vehicle, we can use the exhaust gas from an exhaust gas recirculation (EGR) system as a source of carbon dioxide. Catalytic dry reforming of heavy hydrocarbon is a very difficult reaction due to the high accumulation of carbon on the catalyst. Therefore, we attempted to use a non-equilibrium pulsed plasma for the dry reforming of model diesel fuel without a catalyst. We investigated dry reforming of model diesel fuel (n-dodecane) with a low-energy pulsed spark plasma, which is a kind of non-equilibrium plasma at a low temperature of 523 K. Through the reaction, we were able to obtain syngas (hydrogen and carbon monoxide) and a small amount of C2 hydrocarbon without coke formation at a ratio of CO2/Cfuel = 1.5 or higher. The reaction can be conducted at very low temperatures such as 523 K. Therefore, it is anticipated as a novel and effective process for on-board syngas production from diesel fuel using an EGR system.

Sekine, Yasushi; Furukawa, Naotsugu; Matsukata, Masahiko; Kikuchi, Eiichi

2011-07-01

197

Cooling water distribution system  

DOEpatents

A passive containment cooling system for a nuclear reactor containment vessel. Disclosed is a cooling water distribution system for introducing cooling water by gravity uniformly over the outer surface of a steel containment vessel using an interconnected series of radial guide elements, a plurality of circumferential collector elements and collector boxes to collect and feed the cooling water into distribution channels extending along the curved surface of the steel containment vessel. The cooling water is uniformly distributed over the curved surface by a plurality of weirs in the distribution channels.

Orr, Richard (Pittsburgh, PA)

1994-01-01

198

Application of chemical coagulation aids for the removal of suspended solids (TSS) and phosphorus from the microscreen effluent discharge of an intensive recirculating aquaculture system  

USGS Publications Warehouse

An evaluation of two commonly used coagulation-flocculation aids (alum and ferric chloride) was conducted to determine optimum conditions for treating the backwash effluent from microscreen filters in an intensive recirculating aquaculture system. Tests were carried out to evaluate the dosages and conditions (mixing and flocculation stirring speeds, durations, and settling times) required to achieve optimum waste capture. The orthophosphate removal efficiency for alum and ferric chloride were greater than 90% at a dosage of 60 mg/L. Optimum turbidity removal was achieved with a 60-mg/L dosage for both alum and ferric chloride. Both alum and ferric chloride demonstrated excellent removal of suspended solids from initial total suspended solid values of approximately 320 mg/L to approximately 10 mg/L at a dosage of 60 mg/L. Flocculation and mixing speed and duration played only a minor role in the removal efficiencies for both orthophosphates and suspended solids. Both coagulation-flocculation aids also exhibited excellent settling characteristics, with the majority of the floc quickly settling out in the first 5 min.

Ebeling, J. M.; Ogden, S. R.; Sibrell, P. L.; Rishel, K. L.

2004-01-01

199

Molecular adsorbent recirculating system treatment for acute hepatic failure in patients with hepatitis B undergoing chemotherapy for non-Hodgkin's lymphoma.  

PubMed

Hepatitis B virus (HBV) is a serious cause of morbidity and mortality in hepatitis B surface (HBsAg) antigen-positive patients treated with chemotherapy. Because the hepatitis is related to HBV virological reactivation, application of effective antiviral therapy, such as Lamivudine, has been attempted. Despite the use of these antiviral agents at the time of clinical hepatitis, some HBsAg-positive patients still develop hepatic failure and die. We used the Molecular Adsorbent Recirculating System (MARS) (MARS Monitor; Teraklin AG, Rostock, Germany) to treat 5 HBsAg-positive lymphoma patients with acute hepatic failure due to chemotherapy despite lamivudine treatment. Before and after each treatment we monitored the parameters of neurological status (EEG, cerebral CT and Glasgow coma score), hemodynamic parameters, acid-base equilibrium and blood gases as well as hepatic and renal function. The inclusion criteria were these of the King's College Hospital. Statistical analysis by Student t method showed significant results (P < .01). Three of 5 patients are alive without signs of reactivation of viral or hematological diseases at 1 year follow-up. The 2 patients died because MARS treatment was started too late, with Glascow coma score grade IV, hemodynamic instability, and mechanical ventilator assistance. Despite the limited number of cases, we believe that MARS can be applied to patients with a high tolerance and yield good results, but the treatment has to start at the first signs of hepatic failure. PMID:16182743

Novelli, G; Rossi, M; Ferretti, G; Nudo, F; Bussotti, A; Mennini, G; Novelli, L; Ferretti, S; Antonellis, F; Martelli, S; Berloco, P B

2005-01-01

200

Method for reducing water corrosivity in circulating water systems of petroleum refineries  

SciTech Connect

Under the conditions of recirculating water systems with mixed oxygen/hydrogen depolarization, the authors advise using nontoxic passivating inhibitors, among which the most promising are phosphorus containing reagents, particularly polyphosphates and their combinations with inorganic and organic additives, which give a high level of protection even at concentrations of 15-20 mg/liter. At the Odessa Petroleum Refinery, a combination of sodium nitrite and sodium tripolyphosphate (TPP) has made it possible to achieve more than 85% protection (St3 steel) with a total component concentration of 100-200 mg/liter, with practically no local corrosion in the system. TPP is especially promising when the change is made to industrial installations with closed water systems with combined treatment of water.

Sorochenko, V.F.; Kozlikovskii, Y.B.; Suprunchuk, V.I.

1986-05-01

201

Water system virus detection  

NASA Technical Reports Server (NTRS)

The performance of a waste water reclamation system is monitored by introducing a non-pathogenic marker virus, bacteriophage F2, into the waste-water prior to treatment and, thereafter, testing the reclaimed water for the presence of the marker virus. A test sample is first concentrated by absorbing any marker virus onto a cellulose acetate filter in the presence of a trivalent cation at low pH and then flushing the filter with a limited quantity of a glycine buffer solution to desorb any marker virus present on the filter. Photo-optical detection of indirect passive immune agglutination by polystyrene beads indicates the performance of the water reclamation system in removing the marker virus. A closed system provides for concentrating any marker virus, initiating and monitoring the passive immune agglutination reaction, and then flushing the system to prepare for another sample.

Fraser, A. S.; Wells, A. F.; Tenoso, H. J. (inventors)

1978-01-01

202

Water Powered Bioassay System.  

National Technical Information Service (NTIS)

This project addresses critical technologies, including the acquisition, metering, buffering, delivery and assay for the processing of bio- fluids that enable the complete integration of microfluidic chips into systems. An all-plastic micromachined water-...

L. Lin

2004-01-01

203

Heat recirculating cooler for fluid stream pollutant removal  

DOEpatents

A process by which heat is removed from a reactant fluid to reach the operating temperature of a known pollutant removal method and said heat is recirculated to raise the temperature of the product fluid. The process can be utilized whenever an intermediate step reaction requires a lower reaction temperature than the prior and next steps. The benefits of a heat-recirculating cooler include the ability to use known pollutant removal methods and increased thermal efficiency of the system.

Richards, George A. (Morgantown, WV); Berry, David A. (Morgantown, WV)

2008-10-28

204

Effect of Dietary Supplementation of Brewer's Yeast and GroBiotic®-A on Growth, Immune Responses, and Low-Salinity Tolerance of Pacific White Shrimp Litopenaeus vannamei Cultured in Recirculating Systems  

Microsoft Academic Search

Two separate trials were conducted in clean recirculating systems at salinities of 32.9 (optimal) and 2 ppt (low-salinity challenge) to evaluate brewer's yeast and GroBiotic®-A, a commercial prebiotic, as dietary supplements for growth and health management of Pacific white shrimp Litopenaeus vannamei. The growth-promoting influences of brewer's yeast or GroBiotic®-A previously observed with fish were not demonstrated in these trials

Peng Li; Xiaoxue Wang; Shivananda Murthy; Delbert M. Gatlin III; Frank L. Castille; Addison L. Lawrence

2009-01-01

205

High-pressure gas–liquid equilibrium measurements by means of a double-chamber recirculation apparatus. Data on the system carbon dioxide–limonene at 50 and 70 °C  

Microsoft Academic Search

Measurements of the phase equilibria for the system carbon dioxide–limonene were performed at 50 and 70°C in the pressure range 8.54–13.34MPa. Both the liquid and the gas phase composition were measured. The experiments were carried out by means of a two-chamber recirculation apparatus. According to the procedure, in one of the chambers the gas–liquid equilibrium is established, whereas the second

F. Gironi; M. Maschietti

2010-01-01

206

Automatic hot water recovery system  

Microsoft Academic Search

Heat in the hot water lines of a water system is automatically recovered by providing a bridge conduit between the cold water lines and the hot water lines and by depressurizing the hot water lines relative to the cold water lines thereby to automatically direct higher pressure cold water into the hot water lines through the interconnection, which preferably is

Haws

1982-01-01

207

Validation for a recirculation model.  

PubMed

Recent Clean Air Act regulations designed to reduce volatile organic compound (VOC) emissions have placed new restrictions on painting operations. Treating large volumes of air which contain dilute quantities of VOCs can be expensive. Recirculating some fraction of the air allows an operator to comply with environmental regulations at reduced cost. However, there is a potential impact on employee safety because indoor pollutants will inevitably increase when air is recirculated. A computer model was developed, written in Microsoft Excel 97, to predict compliance costs and indoor air concentration changes with respect to changes in the level of recirculation for a given facility. The model predicts indoor air concentrations based on product usage and mass balance equations. This article validates the recirculation model using data collected from a C-130 aircraft painting facility at Hill Air Force Base, Utah. Air sampling data and air control cost quotes from vendors were collected for the Hill AFB painting facility and compared to the model's predictions. The model's predictions for strontium chromate and isocyanate air concentrations were generally between the maximum and minimum air sampling points with a tendency to predict near the maximum sampling points. The model's capital cost predictions for a thermal VOC control device ranged from a 14 percent underestimate to a 50 percent overestimate of the average cost quotes. A sensitivity analysis of the variables is also included. The model is demonstrated to be a good evaluation tool in understanding the impact of recirculation. PMID:11318387

LaPuma, P T

2001-04-01

208

Heavy metal and waste metabolite accumulation and their potential effect on rainbow trout performance in a replicated water reuse system operated at low or high system flushing rates  

Microsoft Academic Search

A six-month trial was conducted to compare the effects of high and low make-up water flushing rates on rainbow trout performance and water quality in replicated water reuse aquaculture systems (WRAS). Six identical 9.5m3 WRAS, containing a single 5.3m3 tank and operated at a total recirculating flow of 380L\\/min were stocked with 1000 rainbow trout each (133±1g). Three WRAS were

John Davidson; Christopher Good; Carla Welsh; Brian Brazil; Steven Summerfelt

2009-01-01

209

Dynamics of microorganism populations in recirculating nutrient solutions  

NASA Technical Reports Server (NTRS)

This overview covers the basic microbial ecology of recirculating hydroponic solutions. Examples from NASA and Soviet Controlled Ecological Life Support Systems (CELSS) tests and the commercial hydroponic industry will be used. The sources of microorganisms in nutrient solutions include air, water, seeds, plant containers and plumbing, biological vectors, and personnel. Microbial fates include growth, death, and emigration. Important microbial habitats within nutrient delivery systems are root surfaces, hardware surfaces (biofilms), and solution suspension. Numbers of bacteria on root surfaces usually exceed those from the other habitats by several orders of magnitude. Gram negative bacteria dominate the microflora with fungal counts usually much lower. Trends typically show a decrease in counts with increasing time unless stressed plants increase root exudates. Important microbial activities include carbon mineralization and nitrogen transformations. Important detrimental interactions include competition with plants, and human and plant pathogenesis.

Strayer, R. F.

1994-01-01

210

Identification of Bacteria Potentially Responsible for Oxic and Anoxic Sulfide Oxidation in Biofilters of a Recirculating Mariculture System  

Microsoft Academic Search

Bacteria presumably involved in oxygen- or nitrate-dependent sulfide oxidation in the biofilters of a recir- culating marine aquaculture system were identified using a new application of reverse transcription-PCR denaturing gradient gel electrophoresis (DGGE) analysis termed differential-transcription (DT)-DGGE. Bio- filter samples were incubated in various concentrations of sulfide or thiosulfate (0 to 5 mM) with either oxygen or nitrate as the

Eddie Cytryn; Jaap van Rijn; Andreas Schramm; Armin Gieseke; Dirk de Beer; Dror Minz

2005-01-01

211

Water Purification Systems  

NASA Technical Reports Server (NTRS)

Clearwater Pool Technologies employs NASA-developed silver/copper ionization to purify turtle and dolphin tanks, cooling towers, spas, water recycling systems, etc. The pool purifier consists of a microcomputer to monitor water conditions, a pair of metallic electrodes, and a rheostat controller. Ions are generated by passing a low voltage current through the electrodes; the silver ions kill the bacteria, and the copper ions kill algae. This technology has found broad application because it offers an alternative to chemical disinfectants. It was originally developed to purify water on Apollo spacecraft. Caribbean Clear has been using NASA's silver ionization technology for water purification for more than a decade. Two new products incorporate advancements of the basic technology. One is the AquaKing, a system designed for areas with no source of acceptable drinking water. Another is the Caribbean Clear Controller, designed for commercial pool and water park applications where sanitizing is combined with feedback control of pH and an oxidizer, chlorine or bromine. The technology was originally developed to purify water on Apollo spacecraft.

1994-01-01

212

Non-steroidal Anti-Inflammatory Drugs may reduce Enterohepatic Recirculation of Mycophenolic Acid in Patients with Childhood-onset Systemic Lupus Erythematosus  

PubMed Central

Background The large inter-individual differences observed in mycophenolic acid (MPA) pharmacokinetics (MPA-PK) are in part attributed to large variability in enterohepatic recirculation (EHC) of the drug. MPA’s main metabolite, MPA-glucuronide is actively secreted into the bile via the multidrug resistance-associated protein 2 (MRP2) transporter. Non-steroidal anti-inflammatory drugs (NSAIDs) have been shown to inhibit the MRP2 transporter which can alter EHC and drug exposure. Here, we evaluated the effects of this potential drug-transporter interaction on MPA-PK in a cohort for patients with childhood-onset systemic lupus erythematosus (cSLE) on mycophenolate mofetil (MMF) therapy. Methods and Materials Full MPA concentration-time profiles and demographics including co-medications were available for 19 patients with cSLE. Concentrations at pre-dose (Ctrough), 9 hour (C9) and nadir (Cnadir; defined as the lowest concentration between Cmax and C9), and Area under the curve (AUC0–12 and AUC6–12) were assessed using standard methods (WinNonlin5.1). AUC6–12/AUC0–12 and C9/Cnadir ratios were used to evaluate the effect of NSAIDs treatment on MPA-PK. Results Eleven out of 19 patients were on NSAID treatment, and did not show visual evidence of EHC in their PK profile. In contrast, patients not on NSAID therapy showed evidence of EHC-related MPA concentration increase in the later part of their PK profiles, typically after 6h. This phenomenon could be well characterized by the C9/Cnadir ratio, which was significantly lower in the NSAID-treated cohort (P<0.01). Conclusion These preliminary data suggest that concomitant intake of NSAID may lower EHC of MPA possibly through inhibition of MRP2 transport of MPA-G. Further mechanism-based studies are needed to further elucidate this potential transporter interaction.

Fukuda, Tsuyoshi; Brunner, Hermine I.; Sagcal-Gironella, Anna Carmela P.; Vinks, Alexander A.

2014-01-01

213

Solar heating and hot water system installed at Arlington Raquetball Club, Arlington, Virginia  

NASA Technical Reports Server (NTRS)

A solar space and water heating system is described. The solar energy system consists of 2,520 sq. ft. of flat plate solar collectors and a 4,000 gallon solar storage tank. The transfer medium in the forced closed loop is a nontoxic antifreeze solution (50 percent water, 50 percent propylene glycol). The service hot water system consists of a preheat coil (60 ft. of 1 1/4 in copper tubing) located in the upper third of the solar storage tank and a recirculation loop between the preheat coil and the existing electric water heaters. The space heating system consists of two separate water to air heat exchangers located in the ducts of the existing space heating/cooling systems. The heating water is supplied from the solar storage tank. Extracts from site files, specification references for solar modifications to existing building heating and hot water systems, and installation, operation and maintenance instructions are included.

1981-01-01

214

Solar heating and hot water system installed at Arlington Raquetball Club, Arlington, Virginia  

NASA Astrophysics Data System (ADS)

A solar space and water heating system is described. The solar energy system consists of 2,520 sq. ft. of flat plate solar collectors and a 4,000 gallon solar storage tank. The transfer medium in the forced closed loop is a nontoxic antifreeze solution (50 percent water, 50 percent propylene glycol). The service hot water system consists of a preheat coil (60 ft. of 1 1/4 in copper tubing) located in the upper third of the solar storage tank and a recirculation loop between the preheat coil and the existing electric water heaters. The space heating system consists of two separate water to air heat exchangers located in the ducts of the existing space heating/cooling systems. The heating water is supplied from the solar storage tank. Extracts from site files, specification references for solar modifications to existing building heating and hot water systems, and installation, operation and maintenance instructions are included.

1981-05-01

215

Water system virus detection  

NASA Technical Reports Server (NTRS)

A monitoring system developed to test the capability of a water recovery system to reject the passage of viruses into the recovered water is described. A nonpathogenic marker virus, bacteriophage F2, is fed into the process stream before the recovery unit and the reclaimed water is assayed for its presence. Detection of the marker virus consists of two major components, concentration and isolation of the marker virus, and detection of the marker virus. The concentration system involves adsorption of virus to cellulose acetate filters in the presence of trivalent cations and low pH with subsequent desorption of the virus using volumes of high pH buffer. The detection of the virus is performed by a passive immune agglutination test utilizing specially prepared polystyrene particles. An engineering preliminary design was performed as a parallel effort to the laboratory development of the marker virus test system. Engineering schematics and drawings of a fully functional laboratory prototype capable of zero-G operation are presented. The instrument consists of reagent pump/metering system, reagent storage containers, a filter concentrator, an incubation/detector system, and an electronic readout and control system.

Fraser, A. S.; Wells, A. F.; Tenoso, H. J.

1975-01-01

216

Dynamics of microorganism populations in recirculating nutrient solutions  

NASA Technical Reports Server (NTRS)

This overview covers the basic microbial ecology of recirculating hydroponic solutions. Examples from NASA and Soviet CELSS tests and the commercial hydroponic industry will be used. The sources of microorganisms in nutrient solutions include air, water, seeds, plant containers and plumbing, biological vectors, and personnel. Microbial fates include growth, death, and emigration. Important microbial habitats within nutrient delivery systems are root surfaces, hardware surfaces (biofilms), and solution suspension. Numbers of bacteria on root surfaces usually exceed those from the other habitats by several orders of magnitude. Gram negative bacteria dominate the microflora with fungal counts usually much lower. Trends typically show a decrease in counts with increasing time unless stressed plants increase root exudates. Important microbial activities include carbon mineralization and nitrogen transformations. Important detrimental interactions include competition with plants, and human and plant pathogenesis.

Strayer, R. F.

1994-01-01

217

Recirculating induction accelerators for heavy ion fusion  

SciTech Connect

We have recently completed a two-year study of recirculating induction heavy-ion accelerators (recirculators) as low-cost drivers for inertial-fusion-energy power plants. We present here a summary of that study and other recent work on recirculators.

Barnard, J.J.; Deadrick, F. [Lawrence Livermore National Lab., CA (United States); Bangerter, R.O. [Lawrence Berkeley Lab., CA (United States)] [and others

1993-06-21

218

Lattice design for the LHEC recirculating LINAC  

Microsoft Academic Search

In this paper, we present a lattice design for the Large Hadron Electron Collider (LHeC) recirculating linac. The recirculating linac consists of one roughly 3-km long linac hosting superconducting RF (SRF) accelerating cavities, two arcs and one transfer line for the recirculation. In two passes through a pulsed SRF linac the electron beam can get a maximum energy of 140

Y P Sun; C Adolphsen; A Lund Eide; F Zimmermann

2010-01-01

219

Blood cytokine, chemokine and gene expression in cholestasis patients with intractable pruritus treated with a molecular adsorbent recirculating system: A case series  

PubMed Central

BACKGROUND: The molecular adsorbent recirculating system (MARS) is an albumin-dialysis modality that has been investigated predominantly in patients with acute and acute-on-chronic liver failure. OBJECTIVES: To report the clinical efficacy and safety of MARS therapy for intractable pruritus in cholestasis patients with stable chronic liver disease, characterizing the impact of MARS on cytokine levels and on the transcriptome in the blood compartment. METHODS: MARS therapy was performed on three patients with cholestatic liver disease using 8 h runs for two consecutive days. The expression levels of 65 cytokines/chemokines and 24,000 genes were profiled by Luminex (Luminex Corporation, USA) and microarray, respectively. RESULTS: A quality-of-life assessment demonstrated a marked improvement during therapy, which was sustained in two of three patients. No bleeding or infectious complications were observed. Bile acid levels were markedly reduced following MARS (mean [± SD] pretreatment 478.9±112.2 ?mol/L versus post-treatment 89.7±68.8 ?mol/L). Concordant decreases in cytokine/chemokine levels were noted for interleukin (IL)-1beta, IL-2, IL-6, IL-8, IL-12 (p40), RANTES, tranforming growth factor-alpha, tumour necrosis factor-alpha and thrombopoietin following MARS. On microarray profiling, biologically relevant concordant changes among all patients were evident for 20 different genes (10 upregulated and 10 downregulated). The upregulation of several potentially immune suppressive/regulatory genes (eg, early growth response 3 [EGR-3], ephrin-A2 [EFNA2] and serum amyloid A1 [SAA1]), concurrent with downregulation of genes involved in innate immunity (eg, toll-like receptor 4 interactor with leucine-rich repeats [TRIL]) and inflammation (eg, ephrin receptor B1 [EPHB1]), was observed. CONCLUSIONS: This investigative approach offers new insights into intractable pruritus and suggests future therapeutic targets. The clinical benefit of MARS in cholestasis patients with intractable pruritus may not exclusively result from filtration of pruritogens, but also from systemic changes in cytokine/chemokine levels and changes in gene expression of blood cells.

Lisboa, Luiz F; Asthana, Sonal; Kremer, Andreas E; Swain, Mark; Bagshaw, Sean M; Gibney, Noel; Karvellas, Constantine J

2012-01-01

220

Remote water monitoring system  

NASA Technical Reports Server (NTRS)

A remote water monitoring system is described that integrates the functions of sampling, sample preservation, sample analysis, data transmission and remote operation. The system employs a floating buoy carrying an antenna connected by lines to one or more sampling units containing several sample chambers. Receipt of a command signal actuates a solenoid to open an intake valve outward from the sampling unit and communicates the water sample to an identifiable sample chamber. Such response to each signal receipt is repeated until all sample chambers are filled in a sample unit. Each sample taken is analyzed by an electrochemical sensor for a specific property and the data obtained is transmitted to a remote sending and receiving station. Thereafter, the samples remain isolated in the sample chambers until the sampling unit is recovered and the samples removed for further laboratory analysis.

Grana, D. C.; Haynes, D. P. (inventors)

1978-01-01

221

DOGBONE GEOMETRY FOR RECIRCULATING ACCELERATORS.  

SciTech Connect

Most scenarios for accelerating muons require recirculating acceleration. A racetrack shape for the accelerator requires particles with lower energy in early passes to traverse almost the same length of arc as particles with the highest energy. This extra arc length may lead to excess decays and excess cost. Changing the geometry to a dogbone shape, where there is a single linac and the beam turns completely around at the end of the linac, returning to the same end of the linac from which it exited, addresses this problem. In this design, the arc lengths can be proportional to the particle's momentum. This paper proposes an approximate cost model for a recirculating accelerator, attempts to make cost-optimized designs for both racetrack and dogbone geometries, and demonstrates that the dogbone geometry does appear to be more cost effective.

BERG,J.S.; JOHNSTONE,C.; SUMMERS,D.

2001-06-18

222

THERMOSYPHON BATCH AND REGENERATIVE TURBINE RECIRCULATING 18 O(P,N) 18 F WATER TARGETS FOR OPERATION AT HIGH BEAM POWER  

Microsoft Academic Search

AIMS: Improved boiling water target designs and body materials for the production of ( 18 F)fluoride ion have evolved steadily over the last two decades (1), and reliable operation at beam power up to one kilowatt has been achieved. Our goal is to extend this beam power limit to two kW for boiling water targets through use of the thermosyphon

BW Wieland; BC Wright; GT Bida; CD Illan; JM Doster; JC Clark; RC Runkle

223

Experimental and computational study of the developed flow field in a flat plate integrated collector storage (ICS) solar device with recirculation  

SciTech Connect

The flow structure in a flat plate integrated collector storage device, with recirculation of the storage water, is studied experimentally and theoretically. To facilitate flow visualization, an experimental device was constructed by transparent material (Plexiglas). Flow velocities and fluctuations are measured, using a LDV system. A three-dimensional CFD-model was developed using the FLUENT code. The standard k-{omega} model is selected as the most appropriate. The model is validated, with good agreement, against experimental measurements. Furthermore, copper tubes, in the form of embedded heat exchanger, are placed inside the device and another similar 3D model was developed. The model was used to examine the behavior of the system, when the service water enters the heat exchanger, thus being indirectly heated by the stored hot water. It is shown that the outlet temperature of the service water is enough higher, when recirculation occurs. (author)

Gertzos, K.P.; Caouris, Y.G. [Department of Mechanical Engineering and Aeronautics, University of Patras, 265 00 Patras (Greece)

2007-08-15

224

Investigation of sludge re-circulating clarifiers design and optimization through numerical simulation.  

PubMed

In steam thermal power plants (TPP) with open re-circulating wet cooling towers, elimination of water hardness and suspended solids (SS) is performed in clarifiers. Most of these clarifiers are of high efficiency sludge re-circulating type (SRC) with capacity between 500-1,500 m3/hr. Improper design and/or mal-operation of clarifiers in TPPs results in working conditions below design capacity or production of soft water with improper quality (hardness and S.S.). This causes accumulation of deposits in heat exchangers, condenser tubes, cooling and service water pipes and boiler tubes as well as increasing the ionic load of water at the demineralizing system inlet. It also increases the amount of chemical consumptions and produces more liquid and solid waste. In this regard, a software program for optimal design and simulation of SRCs has been developed. Then design parameters of existing SRCs in four TPPs in Iran were used as inputs to developed software program and resulting technical specifications were compared with existing ones. In some cases improper design was the main cause of poor outlet water quality. In order to achieve proper efficiency, further investigations were made to obtain control parameters as well as design parameters for both mal-designed and/or mal-operated SRCs. PMID:14753549

Davari, S; Lichayee, M J

2003-01-01

225

Standards and Guides of Water Treatment and Water Distribution Systems.  

National Technical Information Service (NTIS)

The following five important documents are compiled for design of municipal water treatment facilities and water distribution systems: (1) Ten States Recommended Standards for Water Works; (2) A Public Water Supply Guide--Designing Community Water Systems...

L. K. Wang M. H. S. Wang

1987-01-01

226

Refinery water reuse process optimization  

Microsoft Academic Search

System design for internal and ''end-of-pipe'' water reuse procedures, in which the major portion of refinery wastewater is returned to recirculating towers, covers ranges from the establishment of an initial information base to organizataion of bench and pilot studies. For internal schemes involving cooling tower sidestream softening, this includes a cooling system survey, evaluation of system water chemistry with emphasis

D. R. Brenneman; R. W. Griffin

1979-01-01

227

Recirculation in multiple wave conversions  

SciTech Connect

A one-dimensional multiple wave-conversion model is constructed that allows energy recirculation in ray phase space. Using a modular eikonal approach, the connection coefficients for this model are calculated by ray phase-space methods. Analytical results (confirmed numerically) show that all connection coefficients exhibit interference effects that depend on an interference phase, calculated from the coupling constants and the area enclosed by the intersecting rays. This conceptual model, which focuses on the topology of intersecting rays in phase space, is used to investigate how mode conversion between primary and secondary waves is modified by the presence of a tertiary wave.

Kaufman, A. N.; Brizard, A.J.; Kaufman, A.N.; Tracy, E.R.

2008-07-30

228

Nitrification in Drinking Water Systems  

Microsoft Academic Search

Nitrification is increasingly a concern in United States potable water distribution systems. This paper reviews research on nitrification as it relates to the ammonia levels and unique environments present in potable water distribution systems. Factors affecting nitrification occurrence, nitrification impacts on water quality and corrosion, and nitrification monitoring and control methods are emphasized. The potential role of nitrogen cycling via

Yan Zhang; Nancy Love; Marc Edwards

2009-01-01

229

Automation of Water Supply Systems.  

National Technical Information Service (NTIS)

The report provides an engineering evaluation of the capabilities of various commercially available water quality sensing devices and automated control systems adapted to water treatment plant operation. This state-of-the-art survey was accomplished throu...

W. F. Echelberger M. W. Tenney D. C. Withey B. P. J. Higgins

1975-01-01

230

Osteopontin Prevents Monocyte Recirculation and Apoptosis  

PubMed Central

Cells of the monocyte/macrophage lineage have been shown to be the principal targets for productive HIV-1 replication within the central nervous system. In addition, HIV-1-associated dementia (HAD) has been shown to correlate with macrophage abundance in the brain. While increased entry of monocytes into the brain is thought to initiate this process, mechanisms that prevent macrophage egress from the brain and means that prevent macrophage death may also contribute to cell accumulation. We hypothesized that osteopontin (OPN) was involved in the accumulation of macrophages in the brain in neuroAIDS. Utilizing in vitro model systems, we have demonstrated role of OPN in two distinct aspects of macrophage accumulation: prevention from recirculation, and protection from apoptosis. In these unique mechanisms, osteopontin would aid in macrophage survival and accumulation in the brain, the pathological substrate of HAD.

Burdo, Tricia H.; Wood, Malcolm R.; Fox, Howard S.

2008-01-01

231

Automated Water-Purification System  

NASA Technical Reports Server (NTRS)

Reverse-osmosis system operates and maintains itself with minimal human attention, using programmable controller. In purifier, membranes surround hollow cores through which clean product water flows out of reverse-osmosis unit. No chemical reactions or phase changes involved. Reject water, in which dissolved solids concentrated, emerges from outer membrane material on same side water entered. Flow controls maintain ratio of 50 percent product water and 50 percent reject water. Membranes expected to last from 3 to 15 years.

Ahlstrom, Harlow G.; Hames, Peter S.; Menninger, Fredrick J.

1988-01-01

232

Isobaric vapor–liquid equilibria for water + n-propanol + n-butanol ternary system at atmospheric pressure  

Microsoft Academic Search

Isobaric vapor–liquid equilibrium (VLE) data for water+n-propanol+n-butanol ternary system have been extensively measured at 99.2kPa using a recirculating still. The experimental data were then correlated using the extended UNIQUAC model, in which the binary interaction energy parameters between the three components were obtained through a simplex fitting method. The results showed that the calculated data by the extended UNIQUAC model

Shun’an Wei; Jianhua Zhang; Lichun Dong; Shiyu Tan; Pan Wang; Xuemei Fu; Yongli Qi

2010-01-01

233

Two oilfield water systems  

SciTech Connect

Two subjects are covered in this book: oilfield water treatment for steam flooding and treatment for oil removal. This information has not before been available in a single volume. The steam-flood section describes water treating requirements and softener designs, in addition to scale and corrosion problems in steam floods. The section on oil removal describes four basic oil-water separation mechanisms with fifteen variations in equipment designs.

Bradley, B.W.

1987-01-01

234

Evacuated-Tube Heat-Pipe Solar Collectors Applied to the Recirculation Loop in a Federal Building: Preprint  

SciTech Connect

This paper describes the design, simulation, construction, and initial performance of a solar water heating system (a 360-tube evacuated-tube heat-pipe solar collector, 54 m2 in gross area, 36 m2 in net absorber area) installed at the top of the hot water recirculation loop in the Social Security Administration's Mid-Atlantic Center in Philadelphia. When solar energy is available, water returning to the hot water storage tank is heated by the solar array. This new approach, in contrast to the more conventional approach of preheating incoming water, is made possible by the thermal diode effect of heat pipes and low heat loss from evacuated-tube solar collectors. The simplicity of this approach and its low installation costs support the deployment of solar energy in existing commercial buildings, especially where the roof is some distance away from the water heating system, which is often in the basement. Initial performance measurements of the system are reported.

Walker, A.; Mahjouri, F.; Stiteler, R.

2004-06-01

235

The benefits of flue gas recirculation in waste incineration.  

PubMed

Flue gas recirculation in the incinerator combustion chamber is an operative technique that offers substantial benefits in managing waste incineration. The advantages that can be obtained are both economic and environmental and are determined by the low flow rate of fumes actually emitted if compared to the flue gas released when recirculation is not conducted. Simulations of two incineration processes, with and without flue gas recirculation, have been carried out by using a commercial flowsheeting simulator. The results of the simulations demonstrate that, from an economic point of view, the proposed technique permits a greater level of energy recovery (up to +3%) and, at the same time, lower investment costs as far as the equipment and machinery constituting the air pollution control section of the plant are concerned. At equal treatment system efficiencies, the environmental benefits stem from the decrease in the emission of atmospheric pollutants. Throughout the paper reference is made to the EC legislation in the field of environmental protection, thus ensuring the general validity in the EU of the foundations laid and conclusions drawn henceforth. A numerical example concerning mercury emission quantifies the reported considerations and illustrates that flue gas recirculation reduces emission of this pollutant by 50%. PMID:16516458

Liuzzo, Giuseppe; Verdone, Nicola; Bravi, Marco

2007-01-01

236

Design of Small Water Systems.  

National Technical Information Service (NTIS)

This manual provides guidance and criteria for the design of small water supply, treatment, and distribution systems. For the purpose of this manual, small water systems shall be those having average daily design flow rates of 380,000 liters per day (100 ...

A. J. Genetti

1999-01-01

237

COMMUNITY WATER SYSTEM SURVEY (CWSS)  

EPA Science Inventory

Resource Purpose: The CWSS is a national random sample of approximately 2,000 community water systems. The primary purpose of the CWSS is to provide OGWDW with data on the financial and operating characteristics of water systems. This information is used to support the o...

238

Wind Effect, Recirculation and Thermal Flow Field of a Direct Air-cooled Condenser for a Large Power Plant  

NASA Astrophysics Data System (ADS)

The thermal effect experiments were carried out of a direct air-cooled system in the low speed wind tunnel. The influence of effect factors on recirculation is also discussion, after that the relationship between the thermal flow field structure and recirculation ratio under the cooling tower is analyzed. At last, the engineering measures to reduce or avoid recirculation are proposed. For certain conditions the experimental measurement shows close agreement with numerical values.

Zhao, W. L.; Liu, P. Q.; Duan, H. S.; Zhu, J. Y.

2011-09-01

239

Semi-continuous anaerobic co-digestion of cow manure and steam-exploded Salix with recirculation of liquid digestate.  

PubMed

The effects of recirculating the liquid fraction of the digestate during mesophilic anaerobic co-digestion of steam-exploded Salix and cow manure were investigated in laboratory-scale continuously stirred tank reactors. An average organic loading rate of 2.6 g VS L(-1) d(-1) and a hydraulic retention time (HRT) of 30 days were employed. Co-digestion of Salix and manure gave better methane yields than digestion of manure alone. Also, a 16% increase in the methane yield was achieved when digestate was recirculated and used instead of water to dilute the feedstock (1:1 dilution ratio). The reactor in which the larger fraction of digestate was recirculated (1:3 dilution ratio) gave the highest methane yields. Ammonia and volatile fatty acids did not reach inhibitory levels, and some potentially inhibitory compounds released during steam explosion (i.e., furfural and 5-hydroxy methyl furfural) were only detected at trace levels throughout the entire study period. However, accumulation of solids, which was more pronounced in the recycling reactors, led to decreased methane yields in those systems after three HRTs. Refraining from the use of fresh water to dilute biomass with a high-solids content and obtaining a final digestate with increased dry matter content might offer important economic benefits in full-scale processes. To ensure long-term stability in such an approach, it would be necessary to optimize separation of the fraction of digestate to be recirculated and also perform proper monitoring to avoid accumulation of solids. PMID:24534902

Estevez, Maria M; Sapci, Zehra; Linjordet, Roar; Schnürer, Anna; Morken, John

2014-04-01

240

Lattice Design for the LHEC Recirculating Linac  

SciTech Connect

In this paper, we present a lattice design for the Large Hadron Electron Collider (LHeC) recirculating linac. The recirculating linac consists of one roughly 3-km long linac hosting superconducting RF (SRF) accelerating cavities, two arcs and one transfer line for the recirculation. In two passes through a pulsed SRF linac the electron beam can get a maximum energy of 140 GeV. Alternatively, in the Energy Recovery Linac (ERL) option the beam passes through a CW linac four times (two passes for acceleration and two for deceleration) for a maximum energy of 60 GeV.

Sun, Yipeng; /CERN; Eide, Anders; /CERN; Zimmermann, Frank; /CERN; Adolphsen, Chris; /SLAC

2011-05-20

241

Gas turbine combustor stabilization by heat recirculation  

NASA Technical Reports Server (NTRS)

The feasibility of heat recirculation for stabilization of lean mixtures and emission reduction has been studied in detail for a typical aircraft gas turbine combustor. Thermodynamic calculations have indicated temperature and heat recirculation rates for operation of the combustor over a range of combustion zone equivalence ratios and for varying modes of desired engine operation. Calculations indicate the feasibility of stabilizing the combustion zone at equivalence ratios as low as 0.2 with achievable heat recirculation rates. Detailed chemical kinetic calculations suggest that combustor heat release is maintained with reaction completion substantially before the NO forming reactions, even though CO is rapidly oxidized in this same region.

Ganji, A.; Short, J.; Branch, M. C.; Oppenheim, A. K.

1975-01-01

242

Cyclone reactor with internal separation and axial recirculation  

DOEpatents

A cyclone combustor apparatus contains a circular partition plate containing a central circular aperture is described. The partition plate divides the apparatus into a cylindrical precombustor chamber and a combustor chamber. A coal-water slurry is passed axially into the inlet end of the precombustor chamber, and primary air is passed tangentially into said chamber to establish a cyclonic air flow. Combustion products pass through the partition plate aperture and into the combustor chamber. Secondary air may also be passed tangentially into the combustor chamber adjacent the partition plate to maintain the cyclonic flow. Flue gas is passed axially out of the combustor chamber at the outlet end and ash is withdrawn tangentially from the combustor chamber at the outlet end. A first mixture of flue gas and ash may be tangentially withdrawn from the combustor chamber at the outlet end and recirculated to the axial inlet of the precombustor chamber with the coal-water slurry. A second mixture may be tangentially withdrawn from the outlet end and passed to a heat exchanger for cooling. Cooled second mixture is then recirculated to the axial inlet of the precombustor chamber. In another embodiment a single cyclone combustor chamber is provided with both the recirculation streams of the first mixture and the second mixture. 10 figs.

Becker, F.E.; Smolensky, L.A.

1988-07-19

243

Cyclone reactor with internal separation and axial recirculation  

DOEpatents

A cyclone combustor apparatus contains a circular partition plate containing a central circular aperture. The partition plate divides the apparatus into a cylindrical precombustor chamber and a combustor chamber. A coal-water slurry is passed axially into the inlet end of the precombustor chamber, and primary air is passed tangentially into said chamber to establish a cyclonic air flow. Combustion products pass through the partition plate aperture and into the combustor chamber. Secondary air may also be passed tangentially into the combustor chamber adjacent the partition plate to maintain the cyclonic flow. Flue gas is passed axially out of the combustor chamber at the outlet end and ash is withdrawn tangentially from the combuston chamber at the outlet end. A first mixture of flue gas and ash may be tangentially withdrawn from the combustor chamber at the outlet end and recirculated to the axial inlet of the precombustor chamber with the coal-water slurry. A second mixture of flue gas and ash may be tangentially withdrawn from the outlet end of the combustor chamber and passed to a heat exchanger for cooling. Cooled second mixture is then recirculated to the axial inlet of the precombustor chamber. In another embodiment a single cyclone combustor chamber is provided with both the recirculation streams of the first mixture and the second mixture.

Becker, Frederick E. (Reading, MA); Smolensky, Leo A. (Concord, MA)

1989-01-01

244

The Exploration Water Recovery System  

NASA Technical Reports Server (NTRS)

The Exploration Water Recovery System is designed towards fulfillment of NASA s Vision for Space Exploration, which will require elevation of existing technologies to higher levels of optimization. This new system, designed for application to the Exploration infrastructure, presents a novel combination of proven air and water purification technologies. The integration of unit operations is modified from that of the current state-of-the-art water recovery system so as to optimize treatment of the various waste water streams, contaminant loads, and flow rates. Optimization is achieved primarily through the removal of volatile organic contaminants from the vapor phase prior to their absorption into the liquid phase. In the current state-of-the-art system, the water vapor in the cabin atmosphere is condensed, and the volatile organic contaminants present in that atmosphere are absorbed into the aqueous phase. Removal of contaminants the5 occurs via catalytic oxidation in the liquid phase. Oxidation kinetics, however, dictate that removal of volatile organic contaminants from the vapor phase can inherently be more efficient than their removal from the aqueous phase. Taking advantage of this efficiency reduces the complexity of the water recovery system. This reduction in system complexity is accompanied by reductions in the weight, volume, power, and resupply requirements of the system. Vapor compression distillation technology is used to treat the urine, condensate, and hygiene waste streams. This contributes to the reduction in resupply, as incorporation of vapor compression distillation technology at this point in the process reduces reliance on the expendable ion exchange and adsorption media used in the current state-of-the-art water recovery system. Other proven technologies that are incorporated into the Exploration Water Recovery System include the Trace Contaminant Control System and the Volatile Removal Assembly.

ORourke, Mary Jane E.; Carter, Layne; Holder, Donald W.; Tomes, Kristin M.

2006-01-01

245

Recirculating cross-correlation detector  

DOEpatents

A digital cross-correlation detector is provided in which two time-varying signals are correlated by repetitively comparing data samples stored in digital form to detect correlation between the two signals. The signals are sampled at a selected rate converted to digital form, and stored in separate locations in separate memories. When the memories are filled, the data samples from each memory are first fed word-by-word through a multiplier and summing circuit and each result is compared to the last in a peak memory circuit and if larger than the last is retained in the peak memory. Then the address line to leading signal memory is offset by one byte to affect one sample period delay of a known amount in that memory and the data in the two memories are then multiplied word-by-word once again and summed. If a new result is larger than a former sum, it is saved in the peak memory together with the time delay. The recirculating process continues with the address of the one memory being offset one additional byte each cycle until the address is shifted through the length of the memory. The correlation between the two signals is indicated by the peak signal stored in the peak memory together with the delay time at which the peak occurred. The circuit is faster and considerably less expensive than comparable accuracy correlation detectors.

Andrews, W.H. Jr.; Roberts, M.J.

1985-01-18

246

Picosecond Pulse Recirculation for High Average Brightness Thomson Scattering-based Gamma-ray Sources  

SciTech Connect

Pulse recirculation has been successfully demonstrated with the interaction laser system of LLNL's Thomson-Radiated Extreme X-ray (T-REX) source. The recirculation increased twenty-eight times the intensity of the light coming out of the laser system, demonstrating the capability of increasing the gamma-ray flux emitted by T-REX. The technical approach demonstrated could conceivably increase the average gamma-ray flux output by up to a hundred times.

Semenov, V

2009-05-28

247

CASE FOR DRINKING WATER SYSTEMS  

EPA Science Inventory

The purpose of the study was to present a tool useful to water utilities that not only could analyze historical distribution system reliability data, but also provide a flexible and expandable mechanism for record-keeping enabling overall management of water work's facilities and...

248

Solar hot water heating system  

Microsoft Academic Search

A solar hot water heating system, utilizing preferably a gas-liquid, phase change medium in the collector, employs one heating and storage tank above the collector and a preheating and storage tank below the first tank and preferably also below the collector. A cold water source feeds the inlet of the preheating tank which has its outlet connected to the inlet

1981-01-01

249

Effects of effluent recirculation in vertical-flow constructed wetland on treatment efficiency of livestock wastewater.  

PubMed

Enhancing the treatment efficiency of livestock wastewater by effluent recirculation is investigated in a pilot-scale vertical-flow constructed wetland. The wetland system is composed of downflow and upflow stages, on which narrow-leaf Phragmites communis and common reed Phragmites typhia are planted, respectively; each stage has a dimension of 4 m(2) (2 m x 2 m). Wastewater from the facultative pond is fed into the system intermittently at a flow rate of 0.4 m(3)/d. Recirculation rates of 0, 25%, 50%0, 100% and 150% are adopted to evaluate the effect of the recirculation rate on pollutants removal. This shows that with effluent recirculation the average removal efficiencies of NH4-N, BOD5 and SS obviously increase to 61.7%, 81.3%, and 77.1%, respectively, in comparison with the values of 35.6%o, 50.2%, and 49.3% without effluent recirculation. But the improvement of TP removal is slight, only from 42.3% to 48.9%. The variations of NH4-N, DO and oxidation-reduction potential (ORP) of inflow and outflow reveal that the adoption of effluent recirculation is beneficial to the formation of oxide environment in wetland. The exponential relationships with excellent correlation coefficients (R(2) > 0.93) are found between the removal rates of NH4-N and BOD5 and the recirculation rates. With recirculation the pH value of the outflow decreases as the alkalinity is consumed by the gradually enhanced nitrification process. When recirculation rate is kept constant at 100%, the ambient temperature appears to affect NH4-N removal, but does not have significant influence on BOD5 removal. PMID:17302314

Lian-sheng, He; Hong-liang, Liu; Bei-dou, Xi; Ying-bo, Zhu

2006-01-01

250

High Power Picosecond Laser Pulse Recirculation.  

National Technical Information Service (NTIS)

We designed and constructed a nonlinear crystal-based short pulse recirculation cavity that traps the second harmonic of an incident high power laser. This scheme aims to increase the efficiency of Compton-scattering based light sources.

C. Brown D. Gibson F. Hartemann I. Jovanovic M. Y. Shverdin S. Anderson

2007-01-01

251

Systems and Components Fuel Delivery System, Water Delivery System, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Systems and Components - Fuel Delivery System, Water Delivery System, Derrick Crane System, and Crane System Details - Marshall Space Flight Center, F-1 Engine Static Test Stand, On Route 565 between Huntsville and Decatur , Huntsville, Madison County, AL

252

Water-based intumescent paint  

NASA Technical Reports Server (NTRS)

Article discusses fire-resistant water-based paints made by adding intumescing agents to fluorocarbon coatings. Since these paints are water-based, they do not pollute atmosphere as they dry and can be used in closed-loop air-recirculation system in spacecraft and submarines.

Sauers, D. G.; Nannelli, P.

1979-01-01

253

Remote water-monitoring system  

NASA Technical Reports Server (NTRS)

General-purpose, water-quality sampling process detects microorganisms and integrates sampling, sample preservation, and sample analysis. System overcomes difficulties in correlation of surface measurements with remote measurements and minimizes human error in handling of samples and instrumentation.

Grana, D. C.; Haynes, D. P.

1977-01-01

254

Water Electrolysis Satellite Propulsion System.  

National Technical Information Service (NTIS)

A water electrolysis satellite propulsion system capable of providing 100,000 pound-seconds of impulse during a seven year life was fabricated and tested in three modes of operation -- simple blowdown, helium repressurization and repressurization by oxyge...

J. G. Campbell R. C. Stechman

1973-01-01

255

Clean Water Systems in Mexico  

NSDL National Science Digital Library

In this video segment adapted from Rx for Survival, learn about the importance of clean water and sanitation systems. Hear the story of how, in the early 1990s, Mexico's entry into a North American trade agreement was threatened by a cholera epidemic. Find out how the Mexican government rebuilt the water and sanitation system to stop the spread of the disease and how the investment in clean water helped the country win the trade agreement. A background essay, discussion questions, and standards correlations are also provided.

2010-08-31

256

Ephesus Municipal Water System Analysis  

NSDL National Science Digital Library

This project examines the entire water system of an ancient city, including supply, distribution, use, and drainage. Until now, individual water system elements have been studied as archaeological objects, but infrequently subjected to analysis by such disciplines as fluids engineering and urban history. This work is part of two larger long-term studies, the first concerning the relationship between physical setting and urban growth in the Greco-Roman world, and the second a comparative study of Old and New World water management techniques in the pre-modern period.

Crouch, Dora P.; Ortloff, Charles

1997-12-05

257

Silica Scale Technology and Water Conservation.  

National Technical Information Service (NTIS)

Conservation of water at the Los Alamos Scientific Laboratory (LASL) has been accomplished by recirculating evaporative cooling waters. Because of high silica concentration (80 mg/l) in Los Alamos groundwater, the concentration of recirculating water must...

H. P. Foyt W. S. Midkiff

1976-01-01

258

Coastal and synoptic recirculation affecting air pollutants dispersion: A numerical study  

NASA Astrophysics Data System (ADS)

This study examines the spatial distribution of potential recirculation over the East Mediterranean Sea, and the combined effect of synoptic and meso-scale recirculations on plume dispersion in the region. For this purpose, three case studies are performed by the RAMS-HYPACT modeling system, each for a different synoptic scale flow pattern. Both a quantitative measure of the recirculation potential at each grid cell and particle dispersion are calculated. Although the recirculation index is an Eulerian quantity for the wind field and plume dispersion is a manifestation of the Lagrangian behavior of the wind, good correlation is found between the two. Several locations are identified as having high recirculation potential, including southern Cyprus, the coasts of Israel and Lebanon, the eastern slopes of the Judean Mountains and the Haifa Bay in particular. In the latter location, high recirculation potential could be explained by strong interaction between the land-sea surfaces, curvature of the bay and proximity of the Carmel ridge. It is shown that the synoptic and meso-scale recirculations may, under certain conditions, act together and at the same time in determining particle distribution. Under weak synoptic scale flows, particles are recirculated over the entire East Mediterranean Sea basin, returning onshore after a period of 2-3 days to join freshly emitted particles. At the same time, near-shore land-sea breeze effects cause particles to recirculate on smaller time scales of less then one day, sometimes passing as much as three times over the same airshed. A single elevated emission source is shown to have the potential to impair air quality at a coastal strip as long as 100-200 km upon returning onshore.

Levy, Ilan; Mahrer, Yizhak; Dayan, Uri

259

Amorphous silica scale in cooling waters  

Microsoft Academic Search

In 1968, most of the evaporation cooled recirculating water systems at Los Alamos Scientific Laboratory were nearly inoperable due to scale. These systems, consisting of cooling towers, evaporative water coolers, evaporative condensers, and air washers had been operated on continuous blowdown without chemical treatment. The feedwater contained 80 mg\\/l silica. A successful program of routine chemical addition in the make-up

W. S. Midkiff; H. P. Foyt

1976-01-01

260

Ultrapure Water System for Hemodialysis Therapy  

ClinicalTrials.gov

The Change of Biomarkers CRP, CBC With the Use of Ultra Pure Water System for; Hemodialysis.; The Rate of Adverse Events Such as Hypotension During Hemodialysis Therapy With Ultra Pure Water; System as Compared to Conventional Water System.

2011-07-21

261

Water Monitor System: Phase 1 Test Report.  

National Technical Information Service (NTIS)

Automatic water monitor system was tested with the objectives of assuring high-quality effluent standards and accelerating the practice of reclamation and reuse of water. The NASA water monitor system is described. Various components of the system, includ...

R. E. Taylor E. L. Jeffers

1976-01-01

262

Water Hyacinth Wastewater Treatment System.  

National Technical Information Service (NTIS)

A prototype water hyacinth wastewater treatment system has been in operation for two years at Walt Disney World, near Orlando, Florida. Typically, the hyacinth system removes 80-90% total suspended solids and B.O.D. from the influent stream. Major impacts...

B. R. Schwegler

1983-01-01

263

An ambient water loop system for USP purified water  

Microsoft Academic Search

An ambient loop USP purified water system has been designed and implemented using carbon and ion exchange resin beds, ultraviolet light systems and polishing filters to produce water consistently meeting or exceeding all USP XXIII quality specifications for purified water. The circulation system is constructed of PVDF plastic piping material installed in a continuous fully-drainable loop. The system was sized

B. H. Junker; M. Stanik; J. Adamca; K. LaRiviere; M. Abbatiello; P. Salmon

1997-01-01

264

Water quality diagnosis system for evaluation of reactor water impurities  

Microsoft Academic Search

In recent years, the methods of water chemistry control in boiling water reactor (BWR) plants have become more and more complicated because of the increasingly higher purity of water quality as a result of the sophistication of water chemistry control techniques. A water quality diagnosis system has been developed to improve the reliability of and achieve a high level of

Toshihiko Fukumoto; Yoichi Hayashi; Nobuyuki Oota; Hiroo Igarashi

1991-01-01

265

Optimization of solar water heating systems through water replenishment  

Microsoft Academic Search

In a typical solar water heating system, cold water is replenished into the storage tank as soon as the load is served. However, it is possible to determine the water replenishment profile (i.e., the quantity of the cold makeup water to be supplied to the storage tank over a day) that optimizes the overall system. In this paper, the effect

Govind N. Kulkarni; Shireesh B. Kedare; Santanu Bandyopadhyay

2009-01-01

266

Isobaric vapor–liquid–liquid equilibrium and vapor–liquid equilibrium for the system water–ethanol-1,4-dimethylbenzene at 101.3 kPa  

Microsoft Academic Search

An all-glass, dynamic recirculating still equipped with an ultrasonic homogenizer has been used to determine vapor–liquid (VLE) and vapor–liquid–liquid (VLLE) equilibria. Consistent data have been obtained for the ternary water+ethanol+p-xylene system at 101.3kPa for temperatures in the range of 351.16–365.40K. Experimental results have been used to check the accuracy of the UNIFAC, UNIQUAC and NRTL models in the liquid–liquid region

Vicente Gomis; Ana Pequenín; Juan Carlos Asensi

2009-01-01

267

System and method for removing pollutants from water  

US Patent & Trademark Office Database

A system and method for removing pollutants from wastewater. The system includes a constructed wetland cell in which the filtered wastewater is flowed generally vertically. The flow of wastewater is unsaturated through the wetland cell to aerate the wastewater. The wastewater may be further aerated by a blower or injector. The treated wastewater from the wetland cell is blended with untreated wastewater, then either recirculated through the wetland cell or conveyed to a disposal system.

2003-11-25

268

Seismic Response Modeling of Water Supply Systems.  

National Technical Information Service (NTIS)

This report presents a comprehensive model for simulating the earthquake performance of water supply systems. The model is developed in conjunction with the water system operated by the Los Angeles Department of Water and Power (LADWP) and validated throu...

P. Shi T. D. O'Rourke

2008-01-01

269

Shallow Water Data Collection System  

Microsoft Academic Search

In September 1991, the first of a series of measure- ments was made with high frequency (2 10 kHz) sonar in shal- low waters (35-55 m) of Block Island Sound. Approximately 250 sonar echoes were collected with sonar heads mounted on a re- motely controlled, submersed system towed by a surface ship over various bottom types. For ten types of

R. N. Carpenter; J. G. Kelly; M. Buffman

1992-01-01

270

Reduced Volume Prototype Spacesuit Water Membrane Evaporator; A Next-Generation Evaporative Cooling System for the Advanced Extravehicular Mobility Unit Portable Life Support System  

NASA Technical Reports Server (NTRS)

Development of the Advanced Extravehicular Mobility Unit (AEMU) portable life support subsystem (PLSS) is currently under way at NASA Johnson Space Center. The AEMU PLSS features a new evaporative cooling system, the reduced volume prototype (RVP) spacesuit water membrane evaporator (SWME). The RVP SWME is the third generation of hollow fiber SWME hardware. Like its predecessors, RVP SWME provides nominal crew member and electronics cooling by flowing water through porous hollow fibers. Water vapor escapes through the hollow fiber pores, thereby cooling the liquid water that remains inside of the fibers. This cooled water is then recirculated to remove heat from the crew member and PLSS electronics. Major design improvements, including a 36% reduction in volume, reduced weight, and a more flight-like backpressure valve, facilitate the packaging of RVP SWME in the AEMU PLSS envelope. The development of these evaporative cooling systems will contribute to a more robust and comprehensive AEMU PLSS.

Makinen, Janice V.; Anchondo, Ian; Bue, Grant C.; Campbell, Colin; Colunga, Aaron

2013-01-01

271

Recirculation Bubbles Measured at the Black Rock Forest Site in New York  

NASA Astrophysics Data System (ADS)

In conditions of low or moderate wind speed, large eddy structures - or recirculation bubbles - may form in the atmosphere over complex terrain. Recirculating air can have a significant influence on the exchange of moisture, energy and trace gases between the atmosphere and biosphere. Recirculation bubbles were predicted by an analytical model (Wang and Yi, 2012), and a numerical model (Xu and Yi, 2012). We conducted an experiment using two nearby towers in Black Rock Forest, New York, confirming the predicted phenomenon. Sensors were installed at five different levels on a tower at the top of a forested hill, and at five different levels at the middle of the eastern slope of the same hill. Each tower contained sensors both above and within the canopy measuring wind speed and direction, temperature, carbon dioxide, water vapor, relative humidity, net radiation, ground heat flux and other key parameters. Sensors collected data from 20 April to 9 June, 2013. The energy flux balances at the tops of the hilltop and midslope towers were approximately 75% and 85% of closure, respectively. The formation of recirculation bubbles was observed to be dependent on wind speed and direction, terrain features, temperature gradients and prevailing synoptic conditions. Carbon dioxide, water vapor and temperature profiles show that net ecosystem exchange is influenced by the presence or absence of recirculation. This research was supported by NSF Grants ATM-0930015 and PSC-CUNY ENHC-44-83.

Kutter, E.; Yi, C.; Hendrey, G. R.; Liu, H.; Eaton, T. T.; Ni-Meister, W.

2013-12-01

272

The determination of essential clearance, volume, and residence time parameters of recirculating metabolic systems: The reversible metabolism of methylprednisolone and methylprednisone in rabbits  

Microsoft Academic Search

Methods based on moment analysis are described which permit the calculation of the fundamental parameters of reversible drug\\/metabolite systems. These parameters include the four essential clearances of reversible and irreversible elimination, the central and steady-state distributional volumes, and the sojourn times or turnover rates of the metabolic pair. Additional parameters unique to interconversion systems are developed which describe the properties

William F. Ebling; William J. Jusko

1986-01-01

273

Heat recovery and hot water circulation system  

Microsoft Academic Search

A heat recovery and hot water circulation system for use with refrigeration means and a hot water reservoir is disclosed. A hot water distribution conduit is coupled intermediately to the cold water inlet and hot water outlet of the reservoir for supplying hot water to a remote station having a number of faucets coupled to the distribution conduit, and a

G. W. Keller; R. J. Yaeger

1982-01-01

274

Qualification of a loss-of-recirculation flow model for jet-pump BWRs  

SciTech Connect

Best-estimate analysis capability for boiling water reactors (BWRs) is important for the support of plant operations, since it is necessary to establish realistic response characteristics during normal and anticipated transient conditions. This capability can be used to support startup and periodic tests, emergency planning, operating procedures, load changes, equipment qualification, control and protective system setpoint changes, and simulator validation. Prior to usage, it is necessary to qualify the model by comparisons with measured data. This paper presents one such qualification for analysis of loss-of-recirculation flow events. First, descriptions of the plant and test are provided; then the model is described. Comparisons between the model predictions and measurements are presented along with results from sensitivity studies. The summary reviews the major conclusions.

Kern, R.C.

1987-01-01

275

ELECTROPHORESIS GEL BUFFER RECIRCULATOR FOR UNDER 20 DOLLARS  

EPA Science Inventory

Procedures requiring extended periods of electrophoresis frequently require recirculation of the get buffer in order to reduce gel artifacts. ere we describe a recirculation device which can be built inexpensively and will fit many different model get boxes....

276

Recirculating natural convection solar energy collector  

Microsoft Academic Search

Recirculating natural convection solar energy collectors are disclosed. In one species of the invention, the collector comprises an insulated housing, a cover of glass or other suitable transparent material, a transparent plate of glass or other suitable material mounted inside said housing and spaced apart from the cover, a heat absorber mounted inside the housing and spaced apart from the

Soleau; B. S. Jr

1979-01-01

277

Spiral line recirculating induction accelerator (SLIA)  

NASA Astrophysics Data System (ADS)

The basic physical principles and issues relating to the design of the spiral line recirculating induction accelerator are examined with reference to the current experimental and theoretical programs. The discussion covers the major technical issues, accelerating cell design for SLIA, magnet design options for transition into and out of the accelerating section, and beam transport experiments.

Bailey, Vernon; Putnam, Sidney; Tiefenback, Michael; Nishimoto, Hart; Mondelli, Alfred

1989-07-01

278

Total Water Management, the New Paradigm for Urban Water Systems  

EPA Science Inventory

There is a growing need for urban water managers to take a more holistic view of their water resource systems as population growth, urbanization, and current resource management practices put different stresses on local water resources and urban infrastructure. Total Water Manag...

279

Water monitor system: Phase 1 test report  

NASA Technical Reports Server (NTRS)

Automatic water monitor system was tested with the objectives of assuring high-quality effluent standards and accelerating the practice of reclamation and reuse of water. The NASA water monitor system is described. Various components of the system, including the necessary sensors, the sample collection system, and the data acquisition and display system, are discussed. The test facility and the analysis methods are described. Test results are reviewed, and recommendations for water monitor system design improvement are presented.

Taylor, R. E.; Jeffers, E. L.

1976-01-01

280

MINIMIZATION OF WATER USE IN LEAFY VEGETABLE WASHERS  

EPA Science Inventory

This project was undertaken to construct and test an improved leafy greens washing system employing water recirculation, to characterize the quality of the wash water and waste stream and to make comparisons to conventional washers. The prototype system produced a cleaner product...

281

Effect of makeup water properties on the condenser fouling in power planr cooling system  

SciTech Connect

The thermoelectric power industry in the U.S. uses a large amount of fresh water. As available freshwater for use in thermoelectric power production becomes increasingly limited, use of nontraditional water sources is of growing interest. Utilization of nontraditional water, in cooling systems increases the potential for mineral precipitation on heat exchanger surfaces. In that regard, predicting the accelerated rate of scaling and fouling in condenser is crucial to evaluate the condenser performance. To achieve this goal, water chemistry should be incorporated in cooling system modeling and simulation. This paper addresses the effects of various makeup water properties on the cooling system, namely pH and aqueous speciation, both of which are important factors affecting the fouling rate in the main condenser. Detailed modeling of the volatile species desorption (i.e. CO{sub 2} and NH{sub 3}), the formation of scale in the recirculating system, and the relationship between water quality and the corresponding fouling rates is presented.

Safari, I.; Walker, M.; Abbasian, J.; Arastoopour, H.; Hsieh, M-K.; Dzombak, D.; Miller, D.

2011-01-01

282

Energy optimization of water distribution systems.  

National Technical Information Service (NTIS)

Energy costs associated with pumping treated water into the distribution system and boosting water pressures where necessary is one of the largest expenditures in the operating budget of a municipality. Due to the size and complexity of Detroit's water tr...

1994-01-01

283

Isobaric vapor–liquid and vapor–liquid–liquid equilibrium data for the water–ethanol–hexane system  

Microsoft Academic Search

Isobaric vapor–liquid and vapor–liquid–liquid equilibria were measured for the water–ethanol–hexane system at normal atmospheric pressure. The apparatus used for the determination of vapor–liquid–liquid equilibrium data was an all-glass dynamic recirculating still with an ultrasonic homogenizer coupled to the boiling flask.The experimental data demonstrated the existence of a ternary heterogeneous azeotrope at 329.2K with a composition of 0.105, 0.236 and 0.658mol

V. Gomis; R. Pedraza; M. D. Saquete

2007-01-01

284

The effects of exhaust gas recirculation on diesel combustion and emissions  

Microsoft Academic Search

An investigation was conducted with the aim of identifying and quantifying the effects of exhaust gas recirculation (EGR) on diesel engine combustion and exhaust emissions. Five effects of EGR were identified and investigated experimentally: the reduction in oxygen supply to the engine, participation in the combustion process of carbon dioxide and water vapour present in the EGR, increase in the

N Ladommatos; S Abdelhalim; H Zhao

2000-01-01

285

Multiple trophic levels fueled by recirculation in the Columbia River plume  

Microsoft Academic Search

Large rivers represent gateways for the transport of terrigenous and anthropogenic material to the coastal ocean. Here we document a ?700 km2 recirculation or bulge associated with the Columbia River plume that retains recently discharged river water sufficiently to create a regional bioreactor. Fueled by a fluvial nitrate source, this feature stimulated growth across three trophic levels and may buffer

Raphael M. Kudela; Alexander R. Horner-Devine; Neil S. Banas; Barbara M. Hickey; Tawnya D. Peterson; Ryan M. McCabe; Evelyn J. Lessard; Elizabeth Frame; Kenneth W. Bruland; David A. Jay; Jay O. Peterson; William T. Peterson; P. Michael Kosro; Sherry L. Palacios; Maeve C. Lohan; Edward P. Dever

2010-01-01

286

Cleaning and recirculation of perfluorohexane (C 6F 14) in the STAR-RICH detector  

NASA Astrophysics Data System (ADS)

A RICH detector with a CsI photo-cathode and liquid perfluorohexane radiator has been installed in the STAR experiment at RHIC. The liquid is continuously cleaned and distributed to a quartz containment vessel within the detector by a closed recirculation system. A VUV spectrometer is connected to the system which monitors the optical transparency of the liquid. This measurement provides one of the pieces of information necessary to model the number of Cherenkov photons which reach the pad plane. A description of the liquid recirculation system and the cleaning procedure for the liquid as well as the spectrometer is presented along with results of their performance.

Andres, Y.; Braem, A.; Cozza, D.; Davenport, M.; De Cataldo, G.; Dell Olio, L.; DiBari, D.; DiMauro, A.; Dunlop, J. C.; Finch, E.; Fraissard, D.; Franco, A.; Gans, J.; Ghidini, B.; Harris, J. W.; Horsley, M.; Kunde, G. J.; Lasiuk, B.; Lesenechal, Y.; Majka, R. D.; Martinengo, P.; Morsch, A.; Nappi, E.; Paic, G.; Piuz, F.; Posa, F.; Raynaud, J.; Salur, S.; Sandweiss, J.; Santiard, J. C.; Satinover, J.; Schyns, E.; Smirnov, N.; Van Beelen, J.; Williams, T. D.; Xu, Z.; STAR-RICH Collaboration

287

A prospective randomized open-label crossover trial of regional citrate anticoagulation vs. anticoagulation free liver dialysis by the Molecular Adsorbents Recirculating System  

PubMed Central

Introduction The Molecular Adsorbent Recycling System (MARS) is used to treat patients with liver failure. Observational data suggest that citrate anticoagulation during MARS is feasible. Comparative studies on the optimal anticoagulation regimen during MARS are lacking. The aim of the current study was to evaluate two heparin-free anticoagulation regimens. Methods We performed a prospective randomized open-label crossover study of regional citrate anticoagulation against no anticoagulation. Ten patients (age 55 ± 11 years) with liver failure undergoing MARS treatment were included. The primary endpoint was completion of MARS sessions. Secondary endpoints included treatment efficacy and safety. Longevity of MARS treatment was plotted as a Kaplan-Meier estimate. Fisher's exact test was used for contingency table analysis. Results Of a total of 27 6-hour sessions, four sessions had to be terminated prematurely, three due to occlusive clotting of the extracorporeal circuit and one due to uncontrollable bleeding from the vascular access site. All four events occurred in the group without anticoagulation. Between group comparison demonstrated citrate anticoagulation to significantly increase the likelihood of completed MARS treatment (Fisher's exact test, P 0.04). This translates into higher bilirubin reduction ratios when citrate was applied (reduction ratio 0.25 vs. 0.15, P 0.02). Systemic ionized calcium concentrations were significantly reduced during citrate anticoagulation (P < 0.001) but remained within a safe range. We observed no major adverse events. Conclusions Regional citrate anticoagulation in patients with liver failure is feasible. Citrate anticoagulation provides superior patency of the extracorporeal circuit. Avoidance of anticoagulation during MARS results in significant loss of treatment efficacy, due to treatment downtime. Additional studies are required to identify the optimal anticoagulation regimen for extracorporeal circulation in patients with liver failure.

2012-01-01

288

Water: Life's Elixir in the Solar System  

NSDL National Science Digital Library

This article discusses the possible occurrence of water in our solar system. Topics include the necessity of liquid water for life, distribution of water throughout the solar system, and the possibility that there may be liquid water on Mars or on some of Jupiter's moons.

289

Ozone Treatment in Cooling Water Systems  

Microsoft Academic Search

Ozone treatment for preventing the biofouling in cooling water systems is investigated.In the fresh water system, the separating effect of the ozonated water on the microorganisms such as the sphaerotilus and the zoogloea which adhere to the piping and form the slime is recognized. When the ozonated water is supplied intermittently to the piping without stopping the flow of the

N. Kaiga; T. Seki; K. Iyasu

1989-01-01

290

Performance of the liquid reactivity control system in BWRs (boiling water reactors)  

SciTech Connect

Boiling water reactors rely on the injection of soluble neutron absorbers to control power in case of failure in the control rod (scram) system. Typically this liquid poison'' is injected from eight small holes on a standpipe positioned vertically near the outer edge of the core shroud in the lower plenum. The achievement of control is predicated on good mixing of this injected liquid with the coolant which is recirculating around the core upper plenum and downcomer. However, because the flows are rather low ({approximately}20% of rated with pumps tripped as expected under such conditions) and the injected solution density is much higher than that of the primary fluid, there have been concerns raised about the efficiency and completeness of this mixing. This work provides the first openly available data addressing such concerns. To avoid potentially important scaling compromises, the data were obtained from full-scale simulations. From the experiments performed so far, we can conclude that complete boron mixing (entrainment) will occur for recirculation flow rates down to 8.2% of rated. 3 refs., 60 figs., 2 tabs.

Theofanous, T.G.; Shabana, E.A. (California Univ., Santa Barbara, CA (USA). Dept. of Chemical and Nuclear Engineering)

1989-09-01

291

Conceptual design and thermal-hydraulic characteristics of natural circulation Boiling Water Reactors  

Microsoft Academic Search

A natural circulation boiling water reactor (BWR) with a rated capacity of 600 MW (electric) has been conceptually designed for small- and medium-sized light water reactors. The components and systems in the reactor are simplified by eliminating pumped recirculation systems and pumped emergency core cooling systems. Consequently, the volume of the reactor building is -- 50% of that for current

Y. Kataoka; H. Suzuki; M. Murase; T. Horiuchi; M. Miki

1988-01-01

292

PERFORMANCE EVALUATION OF WATER QUALITY INFORMATION SYSTEMS  

Microsoft Academic Search

ABSTRACT Useful water quality information systems exhibit a competent system design process, compre- hensive documentation of system design and operation, and a routine performance evaluation process. The ,Framework ,for Evaluating ,Water ,Quality Information System ,Performance ,introdu- ced,here,is an instrument,which,can,help,water,quality managers,and,information,systems designers meet these criteria. The Framework has four major phases: (1) evaluation planning, (2) watershed and management system analysis, (3)

Harvey P. Hotto; Thomas G. Sanders; Robert C. Ward; Fort Collins

293

Numerical computations of swirling recirculating flow  

NASA Technical Reports Server (NTRS)

Swirling, recirculating, nonreacting flows were computed using a 2D elliptic program consisting of three tasks. The computations in Task 1 and 2 were made using an independent analysis for the two coaxial swirling flows. The Task 2 computations were made using the measured profiles of the mixing region. In Task 3, a modified 2D elliptic program was employed to include the effects of interaction between the inner and outer streams.

Srinivasan, R.; Mongia, H. C.

1980-01-01

294

High Power Picosecond Laser Pulse Recirculation  

SciTech Connect

We demonstrate a nonlinear crystal-based short pulse recirculation cavity for trapping the second harmonic of an incident high power laser pulse. This scheme aims to increase the efficiency and flux of Compton-scattering based light sources. We demonstrate up to 36x average power enhancement of frequency doubled sub-millijoule picosecond pulses, and 17x average power enhancement of 177 mJ, 10 ps, 10 Hz pulses.

Shverdin, M Y; Jovanovic, I; Semenov, V A; Betts, S M; Brown, C; Gibson, D J; Shuttlesworth, R M; Hartemann, F V; Siders, C W; Barty, C P

2010-04-12

295

Monitoring systems for community water supplies  

NASA Technical Reports Server (NTRS)

Water monitoring system includes equipment and techniques for waste water sampling sensors for determining levels of microorganisms, oxygen, chlorine, and many other important parameters. System includes data acquisition and display system that allows computation of water quality information for real time display.

Taylor, R. E.; Brooks, R. R.; Jeffers, E. L.; Linton, A. T.; Poel, G. D.

1978-01-01

296

A silver ion water sterilization system  

NASA Technical Reports Server (NTRS)

Small amounts of silver are incorporated in mixture of ion exchange resins, and water passing through this mixture is thus exposed to silver ion concentration. System is useful in self-contained water systems except city water systems where residual chlorine level is stipulated.

Parry, E. P.

1971-01-01

297

Electroporation System for Sterilizing Water  

NASA Technical Reports Server (NTRS)

A prototype of an electroporation system for sterilizing wastewater or drinking water has been developed. In electroporation, applied electric fields cause transient and/or permanent changes in the porosities of living cells. Electroporation at lower field strengths can be exploited to increase the efficiency of chemical disinfection (as in chlorination). Electroporation at higher field strengths is capable of inactivating and even killing bacteria and other pathogens, without use of chemicals. Hence, electroporation is at least a partial alternative to chlorination. The transient changes that occur in micro-organisms at lower electric-field strengths include significantly increased uptake of ions and molecules. Such increased uptake makes it possible to achieve disinfection at lower doses of chemicals (e.g., chlorine or ozone) than would otherwise be needed. Lower doses translate to lower costs and reduced concentrations of such carcinogenic chemical byproducts as trichloromethane. Higher electric fields cause cell membranes to lose semipermeability and thereby become unable to function as selective osmotic barriers between the cells and the environment. This loss of function is the cause of the cell death at higher electric-field intensities. Experimental evidence does not indicate cell lysis but, rather, combined leaking of cell proteins out of the cells as well as invasion of foreign chemical compounds into the cells. The concept of electroporation is not new: it has been applied in molecular biology and genetic engineering for decades. However, the laboratory-scale electroporators used heretofore have been built around small (400-microliter) cuvettes, partly because the smallness facilitates the generation of electric fields of sufficient magnitude to cause electroporation. Moreover, most laboratory- scale electroporators have been designed for testing static water. In contrast, the treatment cell in the present system is much larger and features a flow-through geometry, such that electric fields strong enough to effect 99.9- percent disinfection can be applied to water flowing in a pipe.

Schlager, Kenneth J.

2005-01-01

298

Effect of Water Source Pollution on the Water Quality of Shanghai Water Supply System  

Microsoft Academic Search

The paper describes the quality of water source in Shanghai, China and its water supply system. The effect of purification by traditional water treatment process and the effluent biological stability were evaluated by measuring quality parameters in the water supply system. The data showed that the main pollutants in the water source of Huangpu River were organics and ammonia. The

XIAOHUI BAI; XIAOHONG ZHANG; QUN SUN; XINZE WANG; BIN ZHU

2006-01-01

299

Pilot-scale cooling tower to evaluate corrosion, scaling, and biofouling control strategies for cooling system makeup water  

NASA Astrophysics Data System (ADS)

Pilot-scale cooling towers can be used to evaluate corrosion, scaling, and biofouling control strategies when using particular cooling system makeup water and particular operating conditions. To study the potential for using a number of different impaired waters as makeup water, a pilot-scale system capable of generating 27 000 kJ/h heat load and maintaining recirculating water flow with a Reynolds number of 1.92 × 104 was designed to study these critical processes under conditions that are similar to full-scale systems. The pilot-scale cooling tower was equipped with an automatic makeup water control system, automatic blowdown control system, semi-automatic biocide feeding system, and corrosion, scaling, and biofouling monitoring systems. Observed operational data revealed that the major operating parameters, including temperature change (6.6 °C), cycles of concentration (N = 4.6), water flow velocity (0.66 m/s), and air mass velocity (3660 kg/h m2), were controlled quite well for an extended period of time (up to 2 months). Overall, the performance of the pilot-scale cooling towers using treated municipal wastewater was shown to be suitable to study critical processes (corrosion, scaling, biofouling) and evaluate cooling water management strategies for makeup waters of complex quality.

Chien, S. H.; Hsieh, M. K.; Li, H.; Monnell, J.; Dzombak, D.; Vidic, R.

2012-02-01

300

Water activity in polyol\\/water systems: new UNIFAC parameterization  

Microsoft Academic Search

Water activities of a series of polyol\\/water systems were measured with an AquaLab dew point water activity meter at 298 K. The investigated polyols with carbon numbers from n=2-7 are all in liquid state at room temperature and miscible at any molar ratio 5 with water. In aqueous solutions with the same mass concentration, the diols with lower molecular weight

C. Marcolli; Th. Peter

2005-01-01

301

INDUSTRIAL WASTEWATER RECIRCULATION SYSTEM: PRELIMINARY ENGINEERING  

EPA Science Inventory

The report details the preliminary engineering work done at Owens-Corning's (O-C's) Anderson, South Carolina, fibrous glass plant. The purpose of the work was to test, on a pilot plant scale, various technologies to be used to clean up industrial wastewater for a closed-loop syst...

302

Active heat pipe solar water heating system  

SciTech Connect

An ''active heat pipe'' solar water heating system is described. In its primary mode it transfers solar radiation energy from a high temperature solar evaporator to a low temperature water storage tank. For this mode to work properly, refrigerant must be circulated by a variable speed pump/compressor. It is expected that this system will offer better efficiency than conventional solar water systems and heat pump water heaters. This paper summarizes the benefits of active refrigeration cycle control and presents some simulation results comparing active heat pipe solar water heating systems to conventional systems.

Yoshino, H.; Kasayi, H.; Otsuka, N.; Thompson, P.

1983-08-01

303

Bathymetry-Density Interaction as a Driver for Seawater Recirculation in Submarine Groundwater Discharge  

NASA Astrophysics Data System (ADS)

A new mechanism for shallow saltwater recirculation as a component of submarine groundwater discharge (SGD) in coastal areas is proposed and evaluated. The proposed process occurs as a result of the interaction between bedform topography and buoyancy forces without requiring transient forcing (e.g., tides or waves) or currents over the bedform. Under hydrostatic seawater, the equivalent freshwater head is greatest on the seabed surface at the troughs of the bedform and lowest at the crest. In this mechanism, the inverted salinity (and density) profile in the presence of both a bedform on the seafloor and upward flow of fresher groundwater from depth induces a downward flow of saline porewater under the troughs and upward flow under the adjacent crest of the bedform. The magnitude and occurrence of the mechanism were evaluated and tested using the SEAWAT model. The results indicate that this mechanism could drive seawater recirculation and contribute 20 to 30 percent of local SGD under a range of realistic conditions. Bedform shape, hydraulic conductivity, hydraulic head and salinity at depth in the porous media, aquifer thickness, effective porosity, and hydrodynamic dispersion are among the factors that control the occurrence and magnitude of the recirculation of seawater, though the upward flux of fresher water is a dominant control. The hydraulic head at depth generally decreases with distance offshore as the head dissipates with the upward flow and discharge of the deeper fresher groundwater. Thus, one might anticipate the occurrence of a banded pattern—approximately parallel to the shoreline—of saltwater recirculation due to topographic-density interaction. Close to shore, the underlying head might be so large as to preclude saltwater recirculation, and far offshore fresher groundwater at depth may be absent or the head might be so small as to preclude upwards flow of deeper groundwater, thereby also eliminating the saltwater recirculation due to topographic-density interaction.

Konikow, L. F.; Akhavan, M.; Sawyer, A. H.; Michael, H. A.; Langevin, C. D.

2012-12-01

304

BIOFILM IN DRINKING WATER DISTRIBUTION SYSTEMS  

EPA Science Inventory

Throughout the world there are millions of miles of water distribution pipe lines which provide potable water for use by individuals and industry. Some of these water distribution systems have been in service well over one hundred years. Treated water moving through a distributio...

305

Low-conductivity water systems for accelerators  

Microsoft Academic Search

The performance of low-conductivity water (LCW) systems is of critical importance at accelerator facilities. An imbalance of water chemistry, supply temperature, or component availability can have a direct impact on machine performance. Downtime of the LCW system for any reason can result in downtime of the entire accelerator. LCW systems for copper components are similar to stator cooling systems for

R. Dortwegt

2003-01-01

306

Combined air and water pollution control system  

NASA Technical Reports Server (NTRS)

A bioaquatic air pollution control system for controlling both water and atmospheric pollution is disclosed. The pollution control system includes an exhaust for directing polluted gases out of a furnace and a fluid circulating system which circulates fluid, such as waste water, from a source, past the furnace where the fluid flow entrains the pollutants from the furnace. The combined fluid and pollutants are then directed through a rock/plant/microbial filtering system. A suction pump pumps the treated waste water from the filter system past the exhaust to again entrain more pollutants from the furnace where they are combined with the fluid (waste water) and directed to the filter system.

Wolverton, Billy C. (inventor); Jarrell, Lamont (inventor)

1990-01-01

307

Flow Field Features of the Induced Recirculation Zone using Planar Jet Injection.  

NASA Astrophysics Data System (ADS)

The objective of the present work is to study the recirculation bubble induced by injecting a planar jet in to a channel flow. The work is motivated by the desire to provide a flame stabilization environment for ramjet engines without the use of a sudden expansion or bluff-body which incurs drag penalties. A planar jet issuing into a cross flow is used to create a recirculation zone reminiscent of the flow field created downstream of a rearward-facing step configuration which is used in a current ramjet/scramjet systems. The effect of confinement at high momentum flux ratios leads to a saturation of the control of the recirculation bubble size and strength. Comparison to a rearward-facing step flow shows the current method produces higher turbulence levels and larger integral length scales. It is clear that the flow field produced with fluidic injection has potential for flame anchoring and enhancing combustion rates.

Ahmed, Kareem; Forliti, David; Moody, Jack

2006-11-01

308

Silver disinfection in water distribution systems  

NASA Astrophysics Data System (ADS)

Silver was evaluated as disinfectant to maintain water quality in water distribution system. It was used to inhibit growth of two opportunistic bacteria in planktonik form and in biofilm formation in Robbins devices with stainless steel and PVC surfaces. The results of this work show that silver is a potential secondary disinfectant to be used in water distribution systems.

Silvestry Rodriguez, Nadia

309

UV technologies in water purification systems  

Microsoft Academic Search

A Abbssttrraacctt:: UV technologies are being increasingly used in water purification systems, taking advantage of the germicidal properties of UV and also its effect in reducing organic contaminants. This paper discusses the effectiveness of using UV technologies along a water purification chain and the parameters and configurations to be considered when selecting UV lamps for water purification systems. Also described

Ichiro Kano; Daniel Darbouret; Stéphane Mabic

310

Water activity in polyol/water systems: new UNIFAC parameterization  

NASA Astrophysics Data System (ADS)

Water activities of a series of polyol/water systems were measured with an AquaLab dew point water activity meter at 298 K. The investigated polyols with carbon numbers from n=2-7 are all in liquid state at room temperature and miscible at any molar ratio 5 with water. In aqueous solutions with the same mass concentration, the diols with lower molecular weight lead to lower water activities than those with higher molecular weights. For diols with four or more carbon atoms, the hygroscopicity shows considerable differences between isomers: The 1,2-isomers - consisting of a hydrophilic and a hydrophobic part - bind less strongly to water than isomers with a more balanced 10 distribution of the hydroxyl groups. The experimental water activities were compared with the predictions of the group contribution method UNIFAC: the model predictions overestimate the water activity of water/polyol systems of substances with two or more hydroxyl groups and can not describe the decreased binding to water of isomers with hydrophobic tails. To account for the differences between isomers, a modified UNIFAC 15 parameterization was developed, that allows to discriminate between three types of alkyl groups depending on their position in the molecule. These new group-interaction parameters were calculated using water activities of alcohol/water mixtures. This leads to a distinctly improved agreement of model predictions with experimental results while largely keeping the simplicity of the functional group approach.

Marcolli, C.; Peter, Th.

2005-03-01

311

Water activity in polyol/water systems: new UNIFAC parameterization  

NASA Astrophysics Data System (ADS)

Water activities of a series of polyol/water systems were measured with an AquaLab dew point water activity meter at 298K. The investigated polyols with carbon numbers from n=2-7 are all in liquid state at room temperature and miscible at any molar ratio with water. In aqueous solutions with the same molar concentration, the diols with lower molecular weight lead to lower water activities than those with higher molecular weights. For diols with four or more carbon atoms, the hydrophilicity shows considerable differences between isomers: The 1,2-isomers - consisting of a hydrophilic and a hydrophobic part - bind less strongly to water than isomers with a more balanced distribution of the hydroxyl groups. The experimental water activities were compared with the predictions of the group contribution method UNIFAC: the model predictions overestimate the water activity of water/polyol systems of substances with two or more hydroxyl groups and can not describe the decreased binding to water of isomers with hydrophobic tails. To account for the differences between isomers, a modified UNIFAC parameterization was developed, that allows to discriminate between three types of alkyl groups depending on their position in the molecule. These new group interaction parameters were calculated using water activities of alcohol/water mixtures. This leads to a distinctly improved agreement of model predictions with experimental results while largely keeping the simplicity of the functional group approach.

Marcolli, C.; Peter, Th.

2005-06-01

312

Effect of the surfactant Corexit 7664 on uptake of cadmium by organisms and biological matter in a closed circulated brackish-water system  

NASA Astrophysics Data System (ADS)

Juvenile flounder and common mussel from the Baltic Sea were kept in Corexit 7664 (50 µg/l) and cadmium (5 µg/l)-contaminated, recirculated, sea-water systems for 200 days at 15 °C and 20 ‰ S. Accumulation of cadmium with exposure time was measured in several fish tissues and in mussel. There were no differences in the cadmium accumulation by tissues with or without the addition of Corexit 7664. No acute effects of the contaminants on the experimental animals could be noted. Final cadmium concentrations, reached for all biological matter analysed, were 4 times higher than in full-strength sea water.

von Westernhagen, H.; Dethlefsen, V.

1982-03-01

313

Generation of Flat Optical Frequency Comb based on Mach-Zehnder Modulator and Recirculating Frequency Shifter Loop  

NASA Astrophysics Data System (ADS)

We propose a novel scheme to generate optical frequency comb by using Mach-Zehnder modulator and recirculating frequency shifter loop based on IQ modulator driven by radio frequency clock signals. A system of 4 flat and stable comb lines generation based on Mach-Zehnder modulator is set as the seed light source of the recirculating loop. Through theorical analysis and simulation it is shown that the proposed theoretical model is proved in good agreement with simulation results.

Wu, Shibao; Li, Yulong; Fei, Yue; Hu, Faze

2014-06-01

314

Beneficial effects on water management of simple hydraulic structures in wetland systems: the Vallevecchia case study, Italy.  

PubMed

Conflicting water uses in coastal zones demand integrated approaches to achieve sustainable water resources management, protecting water quality while allowing those human activities which rely upon aquatic ecosystem services to thrive. This case study shows that the creation and simple management of hydraulic structures within constructed wetlands can markedly reduce the non-point pollution from agriculture and, simultaneously, benefit agricultural activities, particularly during hot and dry periods. The Vallevecchia wetland system is based on a reclaimed 900 ha-large drainage basin in Northern Italy, where droughts recently impacted agriculture causing water scarcity and saltwater intrusion. Rainwater and drained water are recirculated inside the system to limit saltwater intrusion, provide irrigation water during dry periods and reduce the agricultural nutrient loads discharged into the bordering, eutrophic Adriatic Sea. Monitoring (2003-2009) of water quality and flows highlights that the construction (ended in 2005) of a gated spillway to control the outflow, and of a 200,000 m3 basin for water storage, dramatically increased the removal of nutrients within the system. Strikingly, this improvement was achieved with a minimal management effort, e.g., each year the storage basin was filled once: a simple management of the hydraulic structures would greatly enhance the system efficiency, and store more water to irrigate and limit saltwater intrusion. PMID:22053478

Carrer, G M; Bonato, M; Smania, D; Barausse, A; Comis, C; Palmeri, L

2011-01-01

315

Effect of irradiation on nonlinear optical recirculation cavity performance  

NASA Astrophysics Data System (ADS)

In applications such as the production of hydrogen ions for accelerators in spallation neutron sources, charge stripping of hydrogen ions using high-power lasers represents an attractive technical approach. The use of laser-ion interaction in conjunction with a laser recirculation cavity holds promise for improved efficiency, but the high-radiation environment raises concerns about the longevity of the key components of such a system, especially the nonlinear crystal used for frequency conversion. We present the results of an in-reactor irradiation experiment in which a sample beta-barium borate crystal has been irradiated with fast neutrons and gamma-rays, accompanied with the Monte Carlo analysis of the irradiation dose and its comparison with typical conditions at the Spallation Neutron Source at Oak Ridge National Laboratory. The results suggest that our design of the laser recirculation cavity exhibits a radiation hardness consistent with maintaining enhancement factors of the order of 10 over >10 years, but a more detailed experimental study is needed to investigate the radiation hardness of cavity designs exhibiting greater enhancement factors.

Saitta, M.; Tikhoplav, R.; Jovanovic, I.

2012-02-01

316

Impact of nitrate-enhanced leachate recirculation on gaseous releases from a landfill bioreactor cell.  

PubMed

This study evaluates the impact of nitrate injection on a full scale landfill bioreactor through the monitoring of gaseous releases and particularly N(2)O emissions. During several weeks, we monitored gas concentrations in the landfill gas collection system as well as surface gas releases with a series of seven static chambers. These devices were directly connected to a gas chromatograph coupled to a flame ionisation detector and an electron capture detector (GC-FID/ECD) placed directly on the field. Measurements were performed before, during and after recirculation of raw leachate and nitrate-enhanced leachate. Raw leachate recirculation did not have a significant effect on the biogas concentrations (CO(2), CH(4) and N(2)O) in the gas extraction network. However, nitrate-enhanced leachate recirculation induced a marked increase of the N(2)O concentrations in the gas collected from the recirculation trench (100-fold increase from 0.2 ppm to 23 ppm). In the common gas collection system however, this N(2)O increase was no more detectable because of dilution by gas coming from other cells or ambient air intrusion. Surface releases through the temporary cover were characterized by a large spatial and temporal variability. One automated chamber gave limited standard errors over each experimental period for N(2)O releases: 8.1 +/- 0.16 mg m(-2) d(-1) (n = 384), 4.2 +/- 0.14 mg m(-2) d(-1) (n = 132) and 1.9 +/- 0.10 mg m(-2) d(-1) (n = 49), during, after raw leachate and nitrate-enhanced leachate recirculation, respectively. No clear correlation between N(2)O gaseous surface releases and recirculation events were evidenced. Estimated N(2)O fluxes remained in the lower range of what is reported in the literature for landfill covers, even after nitrate injection. PMID:19297142

Tallec, G; Bureau, C; Peu, P; Benoist, J C; Lemunier, M; Budka, A; Presse, D; Bouchez, T

2009-07-01

317

Water Quality Evaluation of Aquatic Systems.  

National Technical Information Service (NTIS)

Several example applications of water quality models were discussed to provide background into the development of a comprehensive mathematical model capable of evaluating water quality conditions in any river-reservoir system. A need exists for a river-re...

R. G. Willey

1975-01-01

318

Design data brochure: Solar hot water system  

NASA Technical Reports Server (NTRS)

A design calculation is detailed for a single-family residence housing a family of four in a nonspecific geographical area. The solar water heater system is designed to provide 80 gallons of 140 F hot water per day.

1978-01-01

319

An Oil/Water disperser device for use in an oil content Monitor/Control system  

NASA Astrophysics Data System (ADS)

This patent application discloses an oil content monitor/control unit system, including an oil/water disperser device, which is configured to automatically monitor and control processed effluent from an associated oil/water separator so that if the processed effluent exceeds predetermine in-port or at-sea oil concentration lmits, it is either recirculated to an associated oil/water separator via a ship's bilge for additional processing, or diverted to a holding tank for storage. On the other hand, if the oil concentration of the processed effluent is less than predetermine in-port or at-sea limits, it is discharged overboard. The oil/water disperser device is configured to break up any oil present in the processed effluent into uniform droplets for more accurate sensing of the oil present in the processed effluent into uniform droplets for more accurate sensing of the oil-in-water concentration level thereof. The oil/water disperser device has a flow-actuated variable orifice configured into a spring-loaded polyethylene plunger which provides the uniform distribution of oil droplets.

Kempel, F. D.

1985-07-01

320

PILOT SCALE WATER REUSE SYSTEM  

EPA Science Inventory

The efficiency of the treatment technologies is expected to vary with the source water quality. By testing the technologies with various source waters, the research will quantify the limits of the technology: testing the flow rate variations with influent water quality, evalu...

321

Cost analysis of water recovery systems  

NASA Technical Reports Server (NTRS)

Cost and performance data from Gemini, Skylab, and other aerospace and biotechnology programs were analyzed to identify major cost elements required to establish cost estimating relationships for advanced life support subsystems for long range planning in support of earth orbital programs. Cost analysis are presented for five leading water reclamation systems; (1) RITE waste management-water system;(2) reverse osmosis system;(3) multifiltration system;(4) vapor compression system; and(5) closed air evaporation system with electrolytic pretreatment.

Yakut, M. M.

1972-01-01

322

Water Recovery System Evolved for Exploration.  

National Technical Information Service (NTIS)

A new water recovery system designed towards fulfillment of NASA's Vision for Space Exploration is presented. This water recovery system is an evolution of the current state-of-the-art system. Through novel integration of proven technologies for air and w...

M. J. E. ORourke J. L. Perry D. L. Carter

2006-01-01

323

A Tracer Method for Evaluating Recirculation of Pollutant Releases in Buildings  

Microsoft Academic Search

A method is introduced for evaluating recirculation in a building ventilation system from pollutant emissions in or near the building. Tracer was released at a known rate at the point of pollutant emission. Using measured tracer concentrations, the tracer release rate, and an estimate of the pollutant release rate, pollutant concentrations were estimated at the locations in the building where

James P. Rydock; Ove Hermansen

2002-01-01

324

DISTRIBUTION SYSTEM RESEARCH (WATER SUPPLY AND WATER RESOURCES DIVISION)  

EPA Science Inventory

Two water distribution system simulators(DSSs)are now in operation at the USEPA Test and Evaluation (T&E) Facility in Cincinnati, OH. EPA's T&E Facility is a multifaceted research resource in which a wide variety of water treatment and other environmental protection technologies ...

325

Sea water desalination system, McMurdo  

NSF Publications Database

Title : Sea water desalination system, McMurdo Type : Antarctic EAM NSF Org: OD / OPP Date : May 18, 1993 File : opp93104 INITIAL ENVIRONMENTAL EVALUATION REPLACEMENT OF THE SEA WATER DESALINATION SYSTEM, MCMURDO STATION, ANTARCTICA National Science Foundation Office of Polar Programs Washington, DC May 18, 1993 1. INTRODUCTION The U.S. Antarctic Program (USAP) is proposing to replace the Sea Water Desalination System at McMurdo Station, Antarctica, during the 1993-1994 season.

326

Space shuttle galley water system test program  

NASA Technical Reports Server (NTRS)

A water system for food rehydration was tested to determine the requirements for a space shuttle gallery flight system. A new food package concept had been previously developed in which water was introduced into the sealed package by means of a needle and septum. The needle configuration was developed and the flow characteristics measured. The interface between the food package and the water system, oven, and food tray was determined.

1975-01-01

327

Biofilm formation in a hot water system.  

PubMed

The biofilm formation rate was measured in situ in a hot water system in an apartment building by specially designed sampling equipment, and the net growth of the suspended bacteria was measured by incubation of water samples with the indigeneous bacteria. The biofilm formation rate reached a higher level in the hot water distribution system (2.1 d(-1) to 2.3 d(-1)) than in the hot water tank (1.4 d(-1) to 2.2 d(-1)) indicating an important area for surface associated growth. The net growth rate of the suspended bacteria measured in hot water from the top, middle and bottom of the hot water tank, in the sludge, or in the water from the distribution system was negligible. This indicated that bacterial growth took place on the inner surfaces in the hot water system and biofilm formation and detachment of bacteria could account for most of the suspended bacteria actually measured in hot water. Therefore, attempts to reduce the number of bacteria in a hot water system have to include the distribution system as well as the hot water tank. PMID:12448457

Bagh, L K; Albrechtsen, H J; Arvin, E; Ovesen, K

2002-01-01

328

Recirculating linac free-electron laser driver  

NASA Astrophysics Data System (ADS)

This paper describes the design of a recirculating linac as a driver for the suite of seeded free-electron lasers (FELs) proposed in the UK New Light Source (NLS) project. The choice of superconducting technology for NLS is required in order to deliver bunches at high repetition rates up to 1 MHz. This raises the question of whether a shorter linac in recirculating mode can deliver the beam quality required for seeded FELs. To design such a facility, careful layout choices and optimizations must be made to ensure emittance growth is minimized. Effects leading to emittance dilution include chromatic transport terms, incoherent and coherent synchrotron radiation. The design outlined here is based on a modular philosophy to separate beam injection and extraction from a three stage compression scheme. The design uses many novel design concepts and optimizations to deliver the necessary high peak currents while preserving beam quality for seeded FELs. Start-to-end simulations including the FELs show that the necessary pulse coherence and output power can be provided from the beam thus generated.

Williams, Peter H.; Angal-Kalinin, Deepa; Dunning, David J.; Jones, James K.; Thompson, Neil R.

2011-05-01

329

High speed exhaust gas recirculation valve  

SciTech Connect

In order to minimize pollutants such as Nox, internal combustion engines typically include an exhaust gas recirculation (EGR) valve that can be used to redirect a portion of exhaust gases to an intake conduit, such as an intake manifold, so that the redirected exhaust gases will be recycled. It is desirable to have an EGR valve with fast-acting capabilities, and it is also desirable to have the EGR valve take up as little space as possible. An exhaust gas recirculation valve is provided that includes an exhaust passage tube, a valve element pivotally mounted within the exhaust passage tube, a linear actuator; and a gear train. The gear train includes a rack gear operatively connected to the linear actuator, and at least one rotatable gear meshing with the rack gear and operatively connected to the valve element to cause rotation of the valve element upon actuation of the linear actuator. The apparatus provides a highly compact package having a high-speed valve actuation capability.

Fensom, Rod (Peterborough, GB); Kidder, David J. (Peterborough, GB)

2005-01-18

330

Cooling Water Treatment with Ozone  

Microsoft Academic Search

Small scale tests oruan open recirculating cooling system with a cooling water flow of 10 m\\/h conducted for a period of two years have shown that ozone could be a viable alternative to chlorine and other commonly used biocides. An average ozone dosage of 0.05 mg\\/L was applied continuously to the cooling water. Corrosion rates of copper alloy samples immersed

R. Wellauer; M. Oldani

1990-01-01

331

Water resources information systems for regional planning  

Microsoft Academic Search

A water resources information system is an important tool for regional planning of natural resources and, more specifically, for the identification, selection, implementation and evaluation of projects. It should include data on the availability and accessibility of water, on its utilization by human beings and economic activities, and on the organization of water resources management. Main components of such an

Rob Koudstaal; Lawrence M. Nyongesa

332

Liquid Assets: A Water System  

NSDL National Science Digital Library

This segment from a WPSU documentary Liquid Assets succinctly explains how water in New York journeys from its source to our faucets. Although water flows under our feet everyday, we are blissfully unaware of this service and take it for granted.

Wpsu

2008-11-20

333

Water masers in the Saturnian system  

NASA Astrophysics Data System (ADS)

Context: The presence of water has long been seen as a key condition for life in planetary environments. The Cassini spacecraft discovered water vapour in the Saturnian system by detecting absorption of UV emission from a background star. Investigating other possible manifestations of water is essential, one of which, provided physical conditions are suitable, is maser emission. Aims: We report detection of water maser emission at 22 GHz associated with several Kronian satellites using Earth-based radio telescopes. Methods: We searched for water maser emission in the Saturnian system in an observing campaign using the Metsähovi and Medicina radio telescopes. Spectral data were Doppler-corrected over orbital phase for the Saturnian satellites, yielding detections of water maser emission associated with the moons Hyperion, Titan, Enceladus, and Atlas. Results: The detection of Saturnian water molecules by remote astronomical observation can be combined with in situ spacecraft measurements to harmonise the physical model of the Saturnian system.

Pogrebenko, S. V.; Gurvits, L. I.; Elitzur, M.; Cosmovici, C. B.; Avruch, I. M.; Montebugnoli, S.; Salerno, E.; Pluchino, S.; Maccaferri, G.; Mujunen, A.; Ritakari, J.; Wagner, J.; Molera, G.; Uunila, M.

2009-02-01

334

Apollo experience report: Potable water system  

NASA Technical Reports Server (NTRS)

A description of the design and function of the Apollo potable water system is presented. The command module potable water is supplied as a byproduct of the fuel cells. The cells, located in the service module, function primarily to supply electrical energy to the spacecraft. The source of the lunar module potable water is three tanks, which are filled before lift-off. The technique of supplying the water in each of these cases and the problems associated with materials compatibility are described. The chemical and microbiological quality of the water is reviewed, as are efforts to maintain the water in a microbially safe condition for drinking and food mixing.

Sauer, R. L.; Calley, D. J.

1973-01-01

335

Cost analysis of water recovery systems  

NASA Technical Reports Server (NTRS)

A methodology was developed to predict the relevant contributions of the more intangible cost elements encountered in the development of flight-qualified hardware based on an extrapolation of past hardware development experience. Major items of costs within water recovery systems were identified and related to physical and/or performance criteria. Cost and performance data from Gemini, Skylab, and other aerospace and biotechnology programs were analyzed to identify major cost elements required to establish cost estimating relationships for advanced water recovery systems. The results of the study are expected to assist NASA in long-range planning and allocation of resources in a cost effective manner in support of earth orbital programs. This report deals with the cost analysis of the five leading water reclamation systems, namely: (1) RITE waste management-water system, (2) reverse osmosis system, (3) multifiltration system, (4) vapor compression system, and (5) closed air evaporation system with electrolytic pretreatment.

Yakut, M. M.

1973-01-01

336

NASA's Plum Brook Station Water Systems  

NASA Technical Reports Server (NTRS)

Plum Brook Station's water systems were built in the 1940s to support a World War II ordnance production complex. Because the systems had not been analyzed for current NASA usage, it was unknown if they could meet current requirements and codes or if they were efficient for current use. NASA wanted to determine what improvements would be needed or advisable to support its research projects, so it contracted a hydraulic analysis of the raw and domestic water systems. Burgess and Niple determined current water demands and water flow, developed and calibrated models of the two water systems, and evaluated efficiency improvements and cost-cutting options. They recommended replacing some water mains, installing a new service connection, and removing some high-maintenance items (an underground reservoir, some booster pumps, and a tower).

Puzak, Robert M.; Kimpton, Arthur

2006-01-01

337

Prototype solar domestic hot water systems  

NASA Technical Reports Server (NTRS)

Construction of a double wall heat exchanger using soft copper tube coiled around a hot water storage tank was completed and preliminary tests were conducted. Solar transport water to tank potable water heat exchange tests were performed with a specially constructed test stand. Work was done to improve the component hardware and system design for the solar water heater. The installation of both a direct feed system and a double wall heat exchanger system provided experience and site data to enable informative decisions to be made as the solar market expands into areas where freeze protection is required.

1978-01-01

338

A Synergistic Combination of Advanced Separation and Chemical Scale Inhibitor Technologies for Efficient Use of Imparied Water As Cooling Water in Coal-based Power Plants  

Microsoft Academic Search

Nalco Company is partnering with Argonne National Laboratory (ANL) in this project to jointly develop advanced scale control technologies that will provide cost-effective solutions for coal-based power plants to operate recirculating cooling water systems at high cycles using impaired waters. The overall approach is to use combinations of novel membrane separations and scale inhibitor technologies that will work synergistically, with

Jasbir Gill

2010-01-01

339

Biofilm formation in a hot water system  

Microsoft Academic Search

The biofilm formation rate was measured in situ in a hot water system in an apartment building by specially designed sampling equipment, and the net growth of the suspended bacteria was measured by incubation of water samples with the indigeneous bacteria. The biofilm formation rate reached a higher level in the hot water distribution system (2.1 d-1 to 2.3 d-1)

L. K. Bagh; H.-J. Albrechtsen; E. Arvin; K. Ovesen

340

Basics of Solar Heating & Hot Water Systems.  

ERIC Educational Resources Information Center

In presenting the basics of solar heating and hot water systems, this publication is organized from the general to the specific. It begins by presenting functional and operational descriptions of solar heating and domestic hot water systems, outlining the basic concepts and terminology. This is followed by a description of solar energy utilization…

American Inst. of Architects, Washington, DC.

341

Service water system failures and degradations  

Microsoft Academic Search

The Office for Analysis and Evaluation of Operational Data (AEOD) of the U.S. Nuclear Regulatory Commission (NRC) has completed a comprehensive review and evaluation of service water system failures and degradations observed in operating events in light water reactors from 1980 to 1987. The review and evaluation focused on the identification of causes of system failures and degradations, the adequacy

P. Lam; E. Leeds

1989-01-01

342

Space Shuttle Galley Water System Test Program.  

National Technical Information Service (NTIS)

A water system for food rehydration was tested to determine the requirements for a space shuttle gallery flight system. A new food package concept had been previously developed in which water was introduced into the sealed package by means of a needle and...

1975-01-01

343

Solar-powered hot-water system  

NASA Technical Reports Server (NTRS)

Hot-water system requires no external power except solar energy. System is completely self-controlling. It includes solar-powered pump, solar-thermally and hydrothermally operated valves, and storage tank filled with open-celled foam, to maintain thermal stratification in stored water.

Collins, E. R.

1979-01-01

344

Reuse of Treated Internal or External Wastewaters in the Cooling Systems of Coal-Based Thermoelectric Power Plants  

Microsoft Academic Search

This study evaluated the feasibility of using three impaired waters - secondary treated municipal wastewater, passively treated abandoned mine drainage (AMD), and effluent from ash sedimentation ponds at power plants - for use as makeup water in recirculating cooling water systems at thermoelectric power plants. The evaluation included assessment of water availability based on proximity and relevant regulations as well

Radisav Vidic; David Dzombak; Ming-Kai Hsieh; Heng Li; Shih-Hsiang Chien; Yinghua Feng; Indranil Chowdhury; Jason Monnell

2009-01-01

345

Evaluation of recirculating sand filter in a cold climate.  

PubMed

Approximately 30% of Minnesota's residents rely on onsite technologies for their wastewater treatment. There is a growing need for 'alternative' technologies to aid in treatment for difficult sites and sensitive environmental areas. Recirculating sand filters (RSFs) have been used since the 1970s for small communities with flows > 20,000 L per day, but use for small flow application (< 5,000 L/d) has been growing due to its small land use requirement. A research site was developed in southern Minnesota in 1995 to test alternative technologies, including two RSFs. In addition, in 1998, two RSFs were added to existing residential soil treatment systems that were having problems because of inadequate separation and fill soil conditions. All RSFs in this study used 0.6 metres of coarse sand for treatment, were loaded at approximately 204 L per day per square metre (5 gallons per square foot per day) and a recirculation rate of 5:1. All RSFs have effectively reduced Biochemical Oxygen Demand (BOD5), Total Suspended Solids (TSS), Fecal Coliform (FC) and Nutrients (nitrogen and phosphorus). These systems are able to achieve secondary effluent treatment levels for BOD5 and TSS. The median FC reduction was 90% with a value of 5.7 E4 cfu/100 mL, indicating additional treatment is necessary to protect health and the environment. The RSFs consistently removed 25% or more total phosphorus (TP) and 40% or more total nitrogen (TN). The RSFs did not show significantly decreased performance during the winter months. Two of the RSFs receiving rather high strength domestic waste were able to reduce a greater percentage of total nitrogen, indicated that the addition of carbon from the high strength waste is a benefit resulting in greater TN removal. PMID:16104430

Christopherson, S H; Anderson, J L; Gustafson, D M

2005-01-01

346

Vortex dynamics and scalar transport in the wake of a bluff body driven through a steady recirculating flow  

NASA Astrophysics Data System (ADS)

The air ventilation system in wide-body aircraft cabins provides passengers with a healthy breathing environment. In recent years, the increase in global air traffic has amplified contamination risks by airborne flu-like diseases and terrorist threats involving the onboard release of noxious materials. In particular, passengers moving through a ventilated cabin may transport infectious pathogens in their wake. This paper presents an experimental investigation of the wake produced by a bluff body driven through a steady recirculating flow. Data were obtained in a water facility using particle image velocimetry and planar laser induced fluorescence. Ventilation attenuated the downward convection of counter-rotating vortices produced near the free-end corners of the body and decoupled the downwash mechanism from forward entrainment, creating stagnant contaminant regions.

Poussou, Stephane B.; Plesniak, Michael W.

2012-09-01

347

Recirculating Linac Accelerators For Future Muon Facilities  

SciTech Connect

Neutrino Factories (NF) and Muon Colliders (MC) require rapid acceleration of shortlived muons to multi-GeV and TeV energies. A Recirculating Linear Accelerator (RLA) that uses superconducting RF structures can provide exceptionally fast and economical acceleration to the extent that the focusing range of the RLA quadrupoles allows each muon to pass several times through each high-gradient cavity. A new concept of rapidly changing the strength of the RLA focusing quadrupoles as the muons gain energy is being developed to increase the number of passes that each muon will make in the RF cavities, leading to greater cost effectiveness. We discuss the optics and technical requirements for RLA designs, using RF cavities capable of simultaneous acceleration of both m+ and m- species. The design will include the optics for the multi-pass linac and droplet-shaped return arcs.

Yves Roblin, Alex Bogacz, Vasiliy Morozov, Kevin Beard

2012-04-01

348

Nutrient Management in Recirculating Hydroponic Culture  

NASA Technical Reports Server (NTRS)

There is an increasing need to recirculate and reuse nutrient solutions in order to reduce environmental and economic costs. However, one of the weakest points in hydroponics is the lack of information on managing the nutrient solution. Many growers and research scientists dump out nutrient solutions and refill at weekly intervals. Other authors have recommended measuring the concentrations of individual nutrients in solution as a key to nutrient control and maintenance. Dumping and replacing solution is unnecessary. Monitoring ions in solution is not always necessary; in fact the rapid depletion of some nutrients often causes people to add toxic amounts of nutrients to the solution. Monitoring ions in solution is interesting, but it is not the key to effective maintenance.

Bugbee, Bruce

2004-01-01

349

Water turbine system and method of operation  

DOEpatents

A system for providing electrical power from a current turbine is provided. The system includes a floatation device and a mooring. A water turbine structure is provided having an upper and lower portion wherein the lower portion includes a water fillable chamber. A plurality of cables are used to couple the system where a first cable couples the water turbine to the mooring and a second cable couples the floatation device to the first cable. The system is arranged to allow the turbine structure to be deployed and retrieved for service, repair, maintenance and redeployment.

Costin, Daniel P. (Montpelier, VT)

2011-05-10

350

Water turbine system and method of operation  

DOEpatents

A system for providing electrical power from a current turbine is provided. The system includes a floatation device and a mooring. A water turbine structure is provided having an upper and lower portion wherein the lower portion includes a water fillable chamber. A plurality of cables are used to couple the system where a first cable couples the water turbine to the mooring and a second cable couples the floatation device to the first cable. The system is arranged to allow the turbine structure to be deployed and retrieved for service, repair, maintenance and redeployment.

Costin, Daniel P. (Montpelier, VT) [Montpelier, VT

2009-02-10

351

Water Resource System modeling for the US  

NASA Astrophysics Data System (ADS)

We develop a water resource system model of the US (WRS-US) that identifies 99 river basins. The model is built on river basin-specific estimates of water requirements for thermoelectric cooling, irrigation, public supply, self-supply and mining. WRS-US allocates water resources across uses in order to minimize water stress over the year in each river basin. We use the model to predict water stress through to 2050 under two climate policies and two climate models. The largest water stresses are predicted to occur in the South West of the US. Average water stress is not expected to be alleviated by a constrained GHG emission policy by 2050. However, the mitigation policy will reduce inter-annual variability of water stress.

Blanc, E.; Strzepek, K. S.; Schlosser, C. A.; Jacoby, H.; Gueneau, A.; Fant, C.; Rausch, S.; Awadalla, S.

2012-12-01

352

Analysis and prevention of corrosion in T o chopper systems  

Microsoft Academic Search

To neutron choppers at Oak Ridge National Laboratory's Spallation Neutron Source will stop prompt pulses of high-energy neutrons outside the target moderator. Choppers are cooled internally by recirculated distilled water maintained at 15°C. Numerous metallic components are used to fabricate the choppers and cooling system; water contacts many of these components, establishing a corrosion cell. To chopper system corrosion products

Laura R. Skubal; David B. Chojnowski; Raymond Ziegler

2008-01-01

353

Wash water waste pretreatment system  

NASA Technical Reports Server (NTRS)

Investigations were completed on wash waters based on each candidate personal cleansing agent. Evaluations of coagulants, antifoam agents, and the effect of promising antifoams on the chemical precipitation were included. Based on these evaluations two candidate soaps as well as their companion antifoam agents were selected for further work. Operating parameters included the effect of soap concentration, ferric chloride concentration, duration of mixing, and pore size of depth filters on the degree of soap removal. The effect of pressure on water flow through filter cartridges and on the rate of decline of water flow was also investigated. The culmination of the program was the recommendation of a pretreatment concept based on chemical precipitation followed by pressure filtration.

1977-01-01

354

An expert system for water quality modelling  

Microsoft Academic Search

The RAISON-micro (Regional Analysis by Intelligent System ON a micro-computer) expert system is being used to predict the effects of mine effluents on receiving waters in Ontario. The potential of this system to assist regulatory agencies and mining industries to define more acceptable effluent limits was shown in an initial study. This system has been further developed so that the

W. G. Booty; D. C. L. Lam; A. G. Bobba; I. Wong; D. Kay; J. P. Kerby; G. S. Bowen

1992-01-01

355

Data processing for water monitoring system  

NASA Technical Reports Server (NTRS)

Water monitoring data acquisition system is structured about central computer that controls sampling and sensor operation, and analyzes and displays data in real time. Unit is essentially separated into two systems: computer system, and hard wire backup system which may function separately or with computer.

Monford, L.; Linton, A. T.

1978-01-01

356

Water-loop heat pump systems  

Microsoft Academic Search

Water-loop heat pump (WLHP) systems are reliable, versatile, energy-efficient alternatives to conventional systems such as packaged rooftop or central chiller systems. These systems offer low installed costs, unparalleled design flexibility, and an inherent ability to recover heat in a variety of commercial and multifamily residential buildings for both new construction and retrofit markets. Southern California Edison Co. (SCE) teamed with

C. Eley; M. Hydeman

1992-01-01

357

Performance of two-stage vegetable waste anaerobic digestion depending on varying recirculation rates.  

PubMed

Vegetable waste, which characterized by high moisture content, was evaluated as a substrate for biogas production. The effects of recirculation rate (RR) on the performance of two-stage anaerobic digestion were investigated. The system was operated at an organic loading rate of 1.7 g VS/L/d with varying RRs (0, 0.6, 1, and 1.4). Results demonstrated that volumetric biogas production rates in acidogenic reactor increased from approximately 0.2 7 L/L/d to 0.97 L/L/d, when pH is increased from approximately 5.1 to 6.7. These indicate that recirculation of alkaline effluent from the methanogenic reactor helps create a favorable condition for biogas production in the acidogenic reactor. The decrease in chemical oxygen demand (COD) concentrations from approximately 21,000 mg/L to 6800 mg/L was also observed in the acidogenic reactor. This condition may be attributed to dilution under recirculation. The dynamics between hydrolysis and methanogenesis under recirculation indicated that mass transfer capacity between two-stage reactors improved. PMID:24759642

Zuo, Zhuang; Wu, Shubiao; Zhang, Wanqin; Dong, Renjie

2014-06-01

358

Standards and guides of water treatment and water-distribution systems. Manual for 1974-86  

Microsoft Academic Search

The following five important documents are compiled for design of municipal water treatment facilities and water distribution systems: (1) Ten States Recommended Standards for Water Works; (2) A Public Water Supply Guide--Designing Community Water Systems; (3) Water Supply Guide Lines for Public Water Systems; (4) American National Standard for the Thickness Design of Ductile-Iron Pipe; and (5) Designing for Cast

L. K. Wang; M. H. S. Wang

1987-01-01

359

The potable water system in Skylab  

NASA Technical Reports Server (NTRS)

Description of the medical requirements, development, system operation, and in-flight performance of the Skylab potable water system. Emphasized is the description of the unique features involving new space-flight concepts, procedures, and design incorporated in Skylab. The water supplied to the three Skylab missions was preloaded in stainless-steel tanks. These tanks were fitted with positive expulsion stainless-steel bellows. In-flight iodination of the water, for bacterial control, was accomplished as required. An in-flight bactericide monitor was used periodically to determine the level of bactericide in the water. Prior to the delivery of the water to the crewmen for consumption, the water was passed through a cation exchange resin for metallic ion removal and then heated for food reconstitution or chilled for drinking.

Sauer, R. L.; Westover, J. B.

1974-01-01

360

Water Recovery Systems for Exploration Missions  

NASA Technical Reports Server (NTRS)

As NASA prepares for the Vision for Space Exploration, advances in technology for water recovery systems are necessary to enable future missions. This paper examines the proposed water recovery systems for the initial Constellation exploration missions as well as the capability gaps that exist in the current technology portfolio. We discuss how these gaps will be addressed with future technology development. In addition, the paper reviews how the water recovery system matures throughout the sequence of planned exploration missions, to ultimately support a 180-day lunar mission.

Pickering, Karen D.

2007-01-01

361

Captive Water Current Power System  

SciTech Connect

Current energy is converted into shaft power in two stages; First, buoyant power units with stationary hydrofoil wings reach faster than the current speed by sweeping out a captive path. Second, turbines at said power units convert the fast relative local current into shaft power. Power units sweeping along the water surface, using cycloidal turbine methods, as well as power units sweeping on a submerged path, using axial flow turbine methods, are described.

Wuenscher, H. F.; Wuenscher, H. A.

1984-01-31

362

Self-contained ecological watering system  

US Patent & Trademark Office Database

Self-contained ecological watering system, protected against obturations, and capable of irrigating at low cost uniformly and regularly a variety of cultivated areas; the system operates automatically a series of fertirrigation cycles requiring minimum actuation power and reduced water flow rate. The system permits implementation of various configuration including a plurality of local subsystems (1) which are controllable locally or from a remote station (6); each subsystem comprises a container (2) capable of accumulating the volume of liquid to be discharged per cycle, a watering assembly (3) capable of regulating the watering volume and discharging it upon receiving a low power signal; a low consumption electronic control unit (4) capable of determining the frequency and the appropriate time to send said signal; and a low restriction distribution network (5) capable of transporting the water to irrigate the locations in need.

2001-11-06

363

Passive safety injection system using borated water  

SciTech Connect

A passive safety injection system relies on differences in water density to induce natural circulatory flow patterns which help maintain prescribed concentrations of boric acid in borated water, and prevents boron from accumulating in the reactor vessel and possibly preventing heat transfer.

Conway, Lawrence E. (Allegheny, PA); Schulz, Terry L. (Westmoreland, PA)

1993-01-01

364

Framework for designing water quality information systems  

Microsoft Academic Search

Water quality monitoring is viewed as a system which can be defined following the flow of information through its various tasks: (1) sampling; (2) laboratory analysis; (3) data handling; U) data analysis; (5) reporting; and (6) information utilization. To design a successful water quality \\

R. C. WARD

365

OPTIMIZATION OF STATE WATER QUALITY MONITORING SYSTEMS  

EPA Science Inventory

The water quality monitoring activities required of the States under the Federal Water Pollution Control Act Amendments (PL92-500) will require resources well beyond what is likely to be available, if current systems structures and operating procedures are followed. This paper de...

366

Hydro Static Water Level Systems at Fermilab.  

National Technical Information Service (NTIS)

Several Hydrostatic Water Leveling systems (HLS) are in use at Fermilab. Three systems are used to monitor quadrupoles in the Tevatron and two systems are used to monitor ground motion for potential sites for the International Linear Collider (ILC). All s...

H. Jostlein J. A. Guerra J. T. Volk S. U. Hansen T. E. Kiper

2006-01-01

367

Biofilm formation and multiplication of Legionella in a model warm water system with pipes of copper, stainless steel and cross-linked polyethylene.  

PubMed

Legionella pneumophila was grown in a model warm water system with pipes of copper (Cu), stainless steel (SS) and cross-linked polyethylene (PEX) during recirculation of tap water at 25--35 degrees C. Subsequently, domestic use of warm (37 degrees C) water was simulated using tap water with a low AOC concentration (<10 microg C/L). Two times each week the temperature of the water in the electric heaters (not in the pipes) was elevated to 70 degrees C for 30 min. ATP concentrations in the water sampled from the pipes over a 2-year period were significantly different for the pipe materials, with median values of 2.1 ng/l (Cu), 2.5 ng/l (SS) and 4.5 ng/l (PEX), respectively. Median values of the biofilm concentration were similar on Cu and SS (about 630 pg ATP/cm(2)) and 1870 pg ATP/cm(2) on PEX. Legionella multiplied in these biofilms and median values of Legionella concentrations in water were 1500 CFU/l (Cu) and about 4300 CFU/l for SS and PEX. Legionella to ATP ratios in water had median values of about 0.8 CFU/pg. Hot water flushing (70 degrees C) of the pipes on day 552, followed by 2 weeks of recirculation at 37 degrees C, caused strongly increased concentrations of ATP (up to 300 ng/l) and Legionella (>10(7)CFU/l), with about 100 CFU/pg ATP. Concentrations declined to original levels within 1 week of domestic water use, etc. Legionella concentrations in water and biofilms were at the same levels for all materials after 2 years. Hence, copper temporarily limited the growth of Legionella under the applied conditions and a rapid biomass development strongly increased the Legionella to ATP ratio. PMID:16019051

van der Kooij, Dick; Veenendaal, Harm R; Scheffer, Will J H

2005-08-01

368

Concentration of poliovirus in water by molecular filtration.  

PubMed Central

The efficiency of concentrating poliovirus 1 from distilled water samples was determined by using a recirculating-flow molecular filtration system. The most efficient recoveries were achieved against members with a 10,000 nominal molecular weight limit pretreated with flocculated beef extract. This procedure yielded a mean virus recovery of 67%.

Berman, D; Rohr, M E; Safferman, R S

1980-01-01

369

CONCENTRATION OF POLIOVIRUS IN WATER BY MOLECULAR FILTRATION  

EPA Science Inventory

The efficiency of concentrating poliovirus 1 from distilled water samples was determined by using a recirculating-flow molecular filtration system. The most efficient recoveries were achieved against membranes with a 10,000 nominal molecular weight limit pretreated with flocculat...

370

Structural Aspects of Amide-Water Systems.  

National Technical Information Service (NTIS)

Studies have been carried out to evaluate parameters affecting solute-solvent interactions in amide-water systems. A kinetic study, accomplished conductimetrically, has shown that the degradation of urea in aqueous solutions up to 8 M, and at temperatures...

R. E. Lindstrom

1971-01-01

371

Integrated Water Treatment System Performance Evaluation.  

National Technical Information Service (NTIS)

This document describes the results of an evaluation of the current Integrated Water Treatment System (IWTS) operation against design performance and a determination of short term and long term actions recommended to sustain IWTS performance.

R. A. Sexton W. E. Meeuwsen

2009-01-01

372

Tactical Water Distribution System (TWDS) Conduit Test.  

National Technical Information Service (NTIS)

This report summarizes testing conducted by this command for potential conduits/couplings used in the Tactical Water Distribution System. Three conduit/coupling candidates were evaluated on the basis of their hydraulic properties: rigid pipe with groove a...

G. W. Rutherford

1982-01-01

373

INTEGRATED WATER TREATMENT SYSTEM PERFORMANCE EVALUATION  

SciTech Connect

This document describes the results of an evaluation of the current Integrated Water Treatment System (IWTS) operation against design performance and a determination of short term and long term actions recommended to sustain IWTS performance.

SEXTON RA; MEEUWSEN WE

2009-03-12

374

Water Resources Information Systems for Regional Planning.  

National Technical Information Service (NTIS)

A water resources information system is an important tool for regional planning of natural resources and, more specifically, for the identification, selection, implementation and evaluation of projects. It should include data on the availability and acces...

J. P. van der Linden R. Koudstaal L. M. Nyongesa

1989-01-01

375

Systems Analysis of Water Quality Survey Design.  

National Technical Information Service (NTIS)

The design of water quality surveys is being investigated by an interdisciplinary team using systems analysis techniques. The class of surveys under study are nominally fifteen days in length and designed to characterize pollutant types and levels at the ...

B. E. Gilliland J. F. Andrews L. C. Wilcox R. W. Gilchrist T. L. Drake

1973-01-01

376

Advanced Atmospheric Water Vapor DIAL Detection System  

NASA Technical Reports Server (NTRS)

Measurement of atmospheric water vapor is very important for understanding the Earth's climate and water cycle. The remote sensing Differential Absorption Lidar (DIAL) technique is a powerful method to perform such measurement from aircraft and space. This thesis describes a new advanced detection system, which incorporates major improvements regarding sensitivity and size. These improvements include a low noise advanced avalanche photodiode detector, a custom analog circuit, a 14-bit digitizer, a microcontroller for on board averaging and finally a fast computer interface. This thesis describes the design and validation of this new water vapor DIAL detection system which was integrated onto a small Printed Circuit Board (PCB) with minimal weight and power consumption. Comparing its measurements to an existing DIAL system for aerosol and water vapor profiling validated the detection system.

Refaat, Tamer F.; Elsayed-Ali, Hani E.; DeYoung, Russell J. (Technical Monitor)

2000-01-01

377

Prototype solar heating and hot water systems  

NASA Technical Reports Server (NTRS)

Progress made in the development of a solar hot water and space heating system is described in four quarterly reports. The program schedules, technical status and other program activities from 6 October 1976 through 30 September 1977 are provided.

1978-01-01

378

Environmental Control and Life Support System, Water Recovery System  

NASA Technical Reports Server (NTRS)

The Environmental Control and Life Support System (ECLSS) Group of the Flight Projects Directorate at the Marshall Space Flight Center (MSFC) is responsible for designing and building the life support systems that will provide the crew of the International Space Station (ISS) a comfortable environment in which to live and work. This is a close-up view of ECLSS Water Recovery System (WRS) racks. The MSFC's ECLSS Group overseas much of the development of the hardware that will allow a constant supply of clean water for four to six crewmembers aboard the ISS. The WRS provides clean water through the reclamation of wastewaters, including water obtained from the Space Shuttle's fuel cells, crewmember urine, used shower, handwash and oral hygiene water cabin humidity condensate, and Extravehicular Activity (EVA) wastes. The WRS is comprised of a Urine Processor Assembly (UPA), and a Water Processor Assembly (WPA). The UPA accepts and processes pretreated crewmember urine to allow it to be processed along with other wastewaters in the WPA, which removes free gas, organic, and nonorganic constituents before the water goes through a series of multifiltration beds for further purification. Product water quality is monitored primarily through conductivity measurements. Unacceptable water is sent back through the WPA for reprocessing. Clean water is sent to a storage tank. The water must meet stringent purity standards before consumption by the crew. The UPA provided by the MSFC and the WRA is provided by the prime contractor, Hamilton Sundstrand Space Systems, International (HSSSI) from Cornecticut.

2000-01-01

379

Recirculating industrial air: The impact on air compliance and workers` safety case study -- Hill Air Force Base C-130 painting operations. Final report, September 1996--July 1998  

SciTech Connect

Recent Clean Air Act regulations require industries, including aircraft painting facilities, to capture volatile organic compound (VOC) emissions. Because aircraft painting contaminates large airflows with traces of VOCs, conventional air control systems would be prohibitively expensive to apply. Recirculating a portion of the air back into the facility is an option to reduce the amount of air to be treated. A computer model is presented that will calculate air control costs and chemical concentrations at selected recirculation levels. Air concentrations are compared to occupational exposure limits (OELs) to analyze worker safety. The model has a chemical database containing over 1300 chemicals. A case study has been performed on a C-130 aircraft painting facility at Hill Air Force Base, Utah. The model predicts strontium chromate concentrations during application of primer paints will reach 1000 times the OEL, and that the concentration will increase by only 1 or 2% at 90% recirculation. Exposures to strontium chromate and other particulate contaminants are affected only slightly by recirculation because airborne solids are removed efficiently when the air is filtered prior to recirculation. The respiratory protection required for the strontium chromate adequately protects workers from increased concentrations of volatile chemicals, which are caused by recirculation. The model demonstrates that recirculating 75% of the air at the Hill AFB facility has a negligible impact on safety and could save $2.7 million on the initial expenses of a VOC control system.

LaPuma, P.T.

1998-07-20

380

Inhibition of seedling growth of crop species by recirculating root exudates of Bidens pilosa L  

Microsoft Academic Search

The allelopathic effects of root exudates ofBidens pilosa L. on seedling growth ofLactuca sativa L.,Phaseolus vulgaris L.,Zea mays L., andSorghum bicolor (L.) Moench were studied using a root exudate recirculating system that allows continuous exposure of crop plants to allelopathic chemicals. This system maintains an undisturbed rhizosphere and eliminates competition and physical contact between the donor and acceptor plants. Comparison

Gordon A. Stevens; Chung-Shih Tang

1985-01-01

381

Water system microbial check valve development  

NASA Technical Reports Server (NTRS)

A residual iodine microbial check valve (RIMCV) assembly was developed and tested. The assembly is designed to be used in the space shuttle potable water system. The RIMCV is based on an anion exchange resin that is supersaturated with an iodine solution. This system causes a residual to be present in the effluent water which provides continuing bactericidal action. A flight prototype design was finalized and five units were manufactured and delivered.

Colombo, G. V.; Greenley, D. R.; Putnam, D. F.

1978-01-01

382

Design of Intelligent Water Vision System  

Microsoft Academic Search

This paper proposes intelligent Water Vision System(IWVS) that can analyze and process the vision underwater by filming various underwater environments with multi-directional underwater camera that is specifically waterproofed. The existing underwater camera filming method had the weakness in acquiring only one side of vision with single-directional under water camera. Thus this the paper proposed a system in which vision data

Tae-Kwan Jang; Eun-Ju Kim; Dae-Kyeong Kim; Ye-Seul Han; Yoon-Soo Seo; Hyun-Sik Cho; Byung-Soo Lee

2010-01-01

383

WATER QUALITY EARLY WARNING SYSTEMS FOR SOURCE WATER AND DISTRIBUTION SYSTEM MONITORING  

EPA Science Inventory

A variety of probes for use in continuous monitoring of water quality exist. They range from single parameter chemical/physical probes to comprehensive screening systems based on whole organism responses. Originally developed for monitoring specific characteristics of water qua...

384

21 CFR 884.6170 - Assisted reproduction water and water purification systems.  

Code of Federal Regulations, 2011 CFR

...2014-04-01 2014-04-01 false Assisted reproduction water and water purification systems. 884.6170 Section 884.6170...Reproduction Devices § 884.6170 Assisted reproduction water and water purification systems. (a)...

2014-04-01

385

Portable deaerator for deionized water systems  

SciTech Connect

The flowing water deaerator systems were designed and built for the TEMPO microwave pulser. The TEMPO program major goals were to build three one-megavolt, rep-rate pulsers capable of providing high power pulsed microwaves for various susceptibility and biological experiments. The TEMPO machine is a transformer driven water dielectric transmission line pulser. The water in the transmission line is required to have high purity and be bubble-free. The purity of the water is maintained by a filtered deionizing system that was supplied by a local vendor. The deaerating system was unique because it was required to be portable and self-contained. The design was based on a very large existing system (RADLAC II) which was not portable. The present system was scaled down to the approximate size of 2 ft x 4 ft x 7 ft high and mounted on a caster-supported frame for portability. Its small size and closed-loop operation allowed it to fit into a transportable subsystem container which housed the water processing and air supply systems. The following report discusses the design, installation, and operation of this flowing water deaerator.

Lancaster, K.T.

1987-08-01

386

Direct determination of blood recirculation rate in hemodialysis by a conductivity method.  

PubMed

Blood recirculation is one of the key factors of decreasing dialysis efficiency. Determination of recirculation rate (R) is necessary to optimize effective dialysis delivery and to monitor vascular access function. R can be directly measured by a conductivity method in paired filtration dialysis (PFD), a double-compartment hemodiafiltration system that permits direct access to plasma water via the ultrafiltration stream. Measurement of R, in this system, involves the first of two conductivity sensors integrated in a urea monitor (UMS, BelIco-Sorin, Mirandola, Italy), and two saline injections. The rise in conductivity (deltaC1) induced by a 2.7 ml bolus of hypertonic saline 20% (mg/dl) in the arterial line serves for calibration, and is followed by an equivalent injection into the venous line, giving rise to deltaC2. The ratio deltaC2/deltaC1 equals R. A comparison between R values obtained with this method and with the low-flow technique in 31 chronic dialysis patients during 138 PFD sessions is reported. Mean R+/-SD by the conductivity method was 5.1+/-2.0 and 5.7+/-2.0% after 65 and 155 minutes of PFD (correlation coefficient, r = 0.75), whereas it was 6.4+/-4.9% and 5.5+/-4.6% after 30 sec of low blood pump flow for urea and creatinine markers, respectively (r = 0.35). After 120 sec of low flow, mean R increased to 9.0+/-5.1 and 8.8+/-4.6% for urea and creatinine, respectively (r = 0.45). Considerable discrepancies were found in R values measured simultaneously with the two blood markers. Statistically significant differences were found between the two measurement modalities (blood-side and conductivity); the correlation coefficients (r) varied between 0.28 and 0.41. The observed differences in mean R results do not seem considerable from a clinical perspective. The best agreement between blood-side and conductivity R measurements was obtained with Rcreat after 30 sec of low flow. Overall, a wider distribution was found in R values from blood-side determinations, most likely consequent to variability in the dosing method. The conductivity method appears more accurate and simple in assessing total R, and can be readily automated and integrated into the dialysis machine. The authors, therefore, recommend evaluation of R using methods not based on chemical blood concentration values. PMID:9466504

Bosc, J Y; LeBlanc, M; Garred, L J; Marc, J M; Foret, M; Babinet, F; Tetta, C; Canaud, B

1998-01-01

387

Recirculating 1-K-Pot for Pulse-Tube Cryostats  

NASA Technical Reports Server (NTRS)

A paper describes a 1-K-pot that works with a commercial pulse tube cooler for astrophysics instrumentation testbeds that require temperatures <1.7 K. Pumped liquid helium-4 cryostats were commonly used to achieve this temperature. However, liquid helium-4 cryostats are being replaced with cryostats using pulse tube coolers. The closed-cycle 1K-pot system for the pulse tube cooler requires a heat exchanger on the pulse tube, a flow restriction, pump-out line, and pump system that recirculates helium-4. The heat exchanger precools and liquefies helium- 4 gas at the 2.5 to 3.5 K pulse tube cold head. This closed-cycle 1-K-pot system was designed to work with commercially available laboratory pulse tube coolers. It was built using common laboratory equipment such as stainless steel tubing and a mechanical pump. The system is self-contained and requires only common wall power to operate. The lift of 15 mW at 1.1 K and base temperature of 0.97 K are provided continuously. The system can be scaled to higher heat lifts of .30 to 50 mW if desired. Ground-based telescopes could use this innovation to improve the efficiency of existing cryo

Paine, Christopher T.; Naylor, Bret J.; Prouve, Thomas

2013-01-01

388

Hydro static water level systems at Fermilab  

SciTech Connect

Several Hydrostatic Water Leveling systems (HLS) are in use at Fermilab. Three systems are used to monitor quadrupoles in the Tevatron and two systems are used to monitor ground motion for potential sites for the International Linear Collider (ILC). All systems use capacitive sensors to determine the water level of water in a pool. These pools are connected with tubing so that relative vertical shifts between sensors can be determined. There are low beta quadrupoles at the B0 and D0 interaction regions of Tevatron accelerator. These quadrupoles use BINP designed and built sensors and have a resolution of 1 micron. All regular lattice superconducting quadrupoles (a total of 204) in the Tevatron use a Fermilab designed system and have a resolution of 6 microns. Data on quadrupole motion due to quenches, changes in temperature will be presented. In addition data for ground motion for ILC studies caused by natural and cultural factors will be presented.

Volk, J.T.; Guerra, J.A.; Hansen, S.U.; Kiper, T.E.; Jostlein, H.; Shiltsev, V.; Chupyra, A.; Kondaurov, M.; Singatulin, S.

2006-09-01

389

Hanford 200 area (sanitary) waste water system  

SciTech Connect

The US Department of Energy (DOE) Hanford Site is located in southeastern Washington State. The Hanford Site is approximately 1,450 sq. km (560 sq. mi) of semiarid land set aside for activities of the DOE. The reactor fuel processing and waste management facilities are located in the 200 Areas. Over the last 50 years at Hanford dicard of hazardous and sanitary waste water has resulted in billions of liters of waste water discharged to the ground. As part of the TPA, discharges of hazardous waste water to the ground and waters of Washington State are to be eliminated in 1995. Currently sanitary waste water from the 200 Area Plateau is handled with on-site septic tank and subsurface disposal systems, many of which were constructed in the 1940s and most do not meet current standards. Features unique to the proposed new sanitary waste water handling systems include: (1) cost effective operation of the treatment system as evaporative lagoons with state-of-the-art liner systems, and (2) routing collection lines to avoid historic contamination zones. The paper focuses on the challenges met in planning and designing the collection system.

Danch, D.A.; Gay, A.E.

1994-09-01

390

Space Station Freedom regenerative water recovery system configuration selection  

NASA Technical Reports Server (NTRS)

The Space Station Freedom (SSF) must recover water from various waste water sources to reduce 90 day water resupply demands for a four/eight person crew. The water recovery system options considered are summarized together with system configuration merits and demerits, resource advantages and disadvantages, and water quality considerations used to select the SSF water recovery system.

Reysa, R.; Edwards, J.

1991-01-01

391

Recirculating industrial air: The impact on air compliance and workers. Safety case study: Hill Air Force Base C-130 painting operations  

SciTech Connect

The 1990 Clean Air Act Amendment resulted in new environmental regulations called the National Emission Standards for Hazardous Air Pollutants (NESHAPs). Industries such as painting facilities may have to treat large volumes of air, which drives the cost of an air control system. Recirculating a portion of the air back into the facility is an option to reduce the amount of air to be treated. A guided computer model written in Microsoft Excel 97% is developed to analyze worker safety and compliance costs with a focus on recirculation. The model has a chemical database containing over 1300 chemicals and requires inputs such as tasks performed, hazardous products used, and chemical make-up of the products. The model will predict indoor air concentrations in relation to occupational exposure limits (OELs). A case study is performed on a C-130 aircraft painting facility at Hill AFB, UT. The Aerospace NESHAP requires air pollution reductions in aircraft painting operations. The model predicts strontium chromate concentrations found in primer paints will reach 1000 times the OEL. Strontium chromate and other solid particulates are nearly unaffected by recirculation because the air is filtered prior to recirculation. The next highest chemical, hexamethylene diisocyanate (HDI), increases from 2.6 to 10.5 times the OEL at 0% and 75% recirculation, respectively. Due to the level of respiratory protection required for the strontium chromate, workers are well protected from the modest increases in concentrations caused by recirculating 75%. The initial cost of a VOC control system with no recirculation is $4.5 million and $1.8 million at 75% recirculation. To decide the best operating conditions for a facility, all options such as product substitution, operational changes or recirculation should be explored. The model is an excellent tool to evaluate these options.

LaPuma, P.T.

1998-06-29

392

Cooling water treatment with ozone. [WEST GERMANY  

Microsoft Academic Search

Small scale tests on an open recirculating cooling system with a cooling water flow of 10 m³\\/h conducted for a period of two years have shown that ozone could be a viable alternative to chlorine and other commonly used biocides. An average ozone dosage of 0.05 mg\\/L was applied continuously to the cooling water. Corrosion rates of copper alloy samples

R. Wellauer; M. Oldani

2009-01-01

393

Recirculating Peritoneal Dialysis with a Subcutaneous Peritoneal Catheter.  

National Technical Information Service (NTIS)

Ten end stage renal disease patients, 9 of whom were diabetic, were treated with peritoneal dialysis via a subcutaneous peritoneal catheter. Three dialysis formats were used: Intermittent peritoneal dialysis (IPD), recirculating peritoneal dialysis (RPD),...

R. L. Stephen S. C. Jacobsen C. Kablitz W. J. Kolff

1977-01-01

394

Recirculating Peritoneal Dialysis with a Subcutaneous Peritoneal Catheter.  

National Technical Information Service (NTIS)

Nine patients with end stage renal disease have been treated with peritoneal dialysis utilizing a subcutaneous peritoneal catheter as the access route and recirculation (RPD) as the dialysis format, over a period extending from one to eleven months. Seven...

R. L. Stephen S. C. Jacobsen W. J. Kolff E. Atkin-Thor

1976-01-01

395

Improved computer program for the thermal performance of a solar water heater  

Microsoft Academic Search

An improved theoretical model to predict the thermal performance of a natural-recirculation (thermosiphon-flow) solar water heater system is presented. The model considers the entire system to be broken up into a finite number of sections, each individual section having a uniform mean temperature. By considering an energy balance over each section, finite difference equations were written to enable the mean

K ONG

1976-01-01

396

Water impact shock test system  

NASA Technical Reports Server (NTRS)

The basic objective was to design, manufacture, and install a shock test system which, in part, would have the ability to subject test articles weighing up to 1,000 pounds to both half sine and/or full sine pulses having peak levels of up to 50 G's with half sine pulse durations of 100 milliseconds or full sine period duration of 200 milliseconds. The tolerances associated with the aforementioned pulses were +20% and -10% for the peak levels and plus or minus 10% for the pulse durations. The subject shock test system was to be capable of accepting test article sizes of up to 4 feet by 4 feet mounting surface by 4 feet in length.

1977-01-01

397

Transport and error sensitivity in a heavy-ion recirculator  

SciTech Connect

An envelope code has been developed to facilitate the design of a recirculating accelerator for a heavy-ion fusion reactor. A novel feature of the model is the treatment of the beam charge density as a Lagrangian fluid in the axial direction. Transport results for a preliminary recirculator design are presented, and sensitivity of the transport to errors in the magnet strength is discussed. 4 refs., 4 figs.

Sharp, W.M.; Barnard, J.J.; Yu, S.S.

1991-05-01

398

Momentum and heat transfer in a complex recirculating flow  

Microsoft Academic Search

Three-dimensional and turbulent recirculating flows in enclosed spaces occur in many engineering situations. Accurate measurements of momentum- and heat-transfer characteristics are needed for direct engineering-design applications and for developments of numerical-simulation codes of these flows. A facility to generate recirculating flows driven by buoyancy and\\/or shear forces in a rectangular cavity was constructed to model such flows. Also, a visualization

Rhee

1987-01-01

399

Pulsed power requirements for the Sandia recirculating electron beam linac  

Microsoft Academic Search

Compact, high gradient, linear induction accelerators may be achieved by recirculating the electron beam in phase with a repeating accelerating voltage. A two-cavity recirculating accelerator has been designed and operated in a single-pass mode. The prototype accelerator uses a 2.5-MV, 20-kA, 25-ns duration injector and an accelerating cavity that will produce a total accelerating voltage of 5.3 MV for four

W. K. Tucker; S. L. Shope; D. E. Hasti

1987-01-01

400

21 CFR 876.5665 - Water purification system for hemodialysis.  

Code of Federal Regulations, 2013 CFR

...2014-04-01 2014-04-01 false Water purification system for hemodialysis... Therapeutic Devices § 876.5665 Water purification system for hemodialysis. (a) Identification. A water purification system for...

2014-04-01

401

21 CFR 1250.42 - Water systems; constant temperature bottles.  

Code of Federal Regulations, 2012 CFR

...2014-04-01 2014-04-01 false Water systems; constant temperature bottles...Land and Air Conveyances § 1250.42 Water systems; constant temperature bottles. (a) The water system, whether of the pressure or...

2014-04-01

402

21 CFR 876.5665 - Water purification system for hemodialysis.  

Code of Federal Regulations, 2010 CFR

... Water purification system for hemodialysis. 876.5665 Section 876... Water purification system for hemodialysis. (a) Identification. A water purification system for hemodialysis is a device that is intended...

2010-04-01

403

21 CFR 876.5665 - Water purification system for hemodialysis.  

Code of Federal Regulations, 2010 CFR

... Water purification system for hemodialysis. 876.5665 Section 876... Water purification system for hemodialysis. (a) Identification. A water purification system for hemodialysis is a device that is intended...

2009-04-01

404

Distilled Water Distribution Systems. Laboratory Design Notes.  

ERIC Educational Resources Information Center

Factors concerning water distribution systems, including an evaluation of materials and a recommendation of materials best suited for service in typical facilities are discussed. Several installations are discussed in an effort to bring out typical features in selected applications. The following system types are included--(1) industrial…

Sell, J.C.

405

BIOFILMS IN DRINKING WATER DISTRIBUTION SYSTEMS  

EPA Science Inventory

Virtually anywhere a surface comes into contact with the water in a distribution system, one can find biofilms. Biofilms are formed in distribution system pipelines when microbial cells attach to pipe surfaces and multiply to form a film or slime layer on the pipe. Probably withi...

406

Engineering aspects of water pollution control systems  

Microsoft Academic Search

The importance of proper engineering when providing pollution control systems is emphasized. Organization of engineering projects is described in detail. Included are discussions of: (1) collection and evaluation of available data; (2) establishment of survey and test program; (3) integration and evaluation of findings; (4) establishment of pollution control and water utilization systems; and (5) specification and detailed design preparation.

R. G. Dalbke; A. J. Turk

1967-01-01

407

Army Energy and Water Reporting System Assessment.  

National Technical Information Service (NTIS)

There are many areas of desired improvement for the Army Energy and Water Reporting System. The purpose of system is to serve as a data repository for collecting information from energy managers, which is then compiled into an annual energy report. This d...

M. J. Glardinelli P. C. Deprez

2011-01-01

408

A tracer method for evaluating recirculation of pollutant releases in buildings.  

PubMed

A method is introduced for evaluating recirculation in a building ventilation system from pollutant emissions in or near the building. Tracer was released at a known rate at the point of pollutant emission. Using measured tracer concentrations, the tracer release rate, and an estimate of the pollutant release rate, pollutant concentrations were estimated at the locations in the building where the tracer was measured. The method can be used to test whether a ventilation system is adequate for maintaining an acceptable work environment before work with a hazardous substance begins. In a case study presented to illustrate the technique, initial attempts to correct a problem of recirculation of sulfuric acid from a fume hood in a chemistry laboratory were shown to be inadequate, prompting the ventilation contractor to make further repairs before work with sulfuric acid could be resumed. PMID:11975662

Rydock, James P; Hermansen, Ove

2002-01-01

409

Thermal-hydraulic tests of a recirculation cooling installation for the Rostov nuclear power station  

NASA Astrophysics Data System (ADS)

Results obtained from thermal-hydraulic tests of the recirculation cooling installation used as part of the air cooling system under the containments of the Rostov nuclear power station Units 3 and 4 are presented. The operating modes of the installation during normal operation (air cooling on the surface of finned tubes), under the conditions of anticipated operational occurrences (air cooling and steam condensation from a steam-air mixture), and during an accident (condensation of pure steam) are considered. Agreement is obtained between the results of tests and calculations carried out according to the recommendations given in the relevant regulatory documents. A procedure of carrying out thermal calculation for the case of steam condensation from a steam-air mixture on the surface of fins is proposed. The possibility of efficient use of the recirculation cooling installation in the system for reducing emergency pressure under the containment of a nuclear power station is demonstrated.

Balunov, B. F.; Balashov, V. A.; Il'in, V. A.; Krayushnikov, V. V.; Lychakov, V. D.; Meshalkin, V. V.; Ustinov, A. N.; Shcheglov, A. A.

2013-09-01

410

Antral recirculation in the stomach during gastric mixing.  

PubMed

We investigate flow in the stomach during gastric mixing using a numerical simulation with an anatomically realistic geometry and free-surface flow modeling. Because of momentum differences between greater and lesser curvatures during peristaltic contractions, time-averaged recirculation is generated in the antrum, with retropulsive flow away from the pylorus and compensation flow along the greater curvature toward the pylorus. Gastric content in the distal stomach is continuously transported to the distal antrum by the forward flow of antral recirculation, and it is then mixed by the backward retropulsive flow. Hence, the content inside the antral recirculation is well mixed independently of initial location, whereas the content outside the recirculation is poorly mixed. Free-surface modeling enables us to analyze the effects of posture on gastric mixing. In the upright, prone, and right lateral positions, most of the antrum is filled with content, and the content is well mixed by antral recirculation. In contrast, in the supine and left lateral positions, most of the content is located outside antral recirculation, which results in poor mixing. The curved, twisted shape of the stomach substantially supports gastric mixing in fluid mechanical terms. PMID:23275619

Imai, Yohsuke; Kobayashi, Ikuma; Ishida, Shunichi; Ishikawa, Takuji; Buist, Martin; Yamaguchi, Takami

2013-03-01

411

Sodium molybdate corrosion inhibitor for boiler feedwater systems  

Microsoft Academic Search

Molybdate-containing corrosion inhibotors are becoming more attractive in an increasing number of commercial applications. Sodium molybdate inhibits corrosion of low carbon steel, copper and brass in recirculating cooling water systems while being environmentally safe. These compounds are also economical at the concentration required for effective water treatment. Molybdenum is tolerated in various concentrations by many life forms. Molybdenum compounds are

Robitaille

1979-01-01

412

In-situ continuous water monitoring system  

DOEpatents

An in-situ continuous liquid monitoring system for continuously analyzing volatile components contained in a water source comprises: a carrier gas supply, an extraction container and a mass spectrometer. The carrier gas supply continuously supplies the carrier gas to the extraction container and is mixed with a water sample that is continuously drawn into the extraction container by the flow of carrier gas into the liquid directing device. The carrier gas continuously extracts the volatile components out of the water sample. The water sample is returned to the water source after the volatile components are extracted from it. The extracted volatile components and the carrier gas are delivered continuously to the mass spectrometer and the volatile components are continuously analyzed by the mass spectrometer. 2 figs.

Thompson, C.V.; Wise, M.B.

1998-03-31

413

In-situ continuous water monitoring system  

DOEpatents

An in-situ continuous liquid monitoring system for continuously analyzing volatile components contained in a water source comprises: a carrier gas supply, an extraction container and a mass spectrometer. The carrier gas supply continuously supplies the carrier gas to the extraction container and is mixed with a water sample that is continuously drawn into the extraction container by the flow of carrier gas into the liquid directing device. The carrier gas continuously extracts the volatile components out of the water sample. The water sample is returned to the water source after the volatile components are extracted from it. The extracted volatile components and the carrier gas are delivered continuously to the mass spectrometer and the volatile components are continuously analyzed by the mass spectrometer.

Thompson, Cyril V. (Knoxville, TN); Wise, Marcus B. (Kingston, TN)

1998-01-01

414

An expert system for water quality modelling.  

PubMed

The RAISON-micro (Regional Analysis by Intelligent System ON a micro-computer) expert system is being used to predict the effects of mine effluents on receiving waters in Ontario. The potential of this system to assist regulatory agencies and mining industries to define more acceptable effluent limits was shown in an initial study. This system has been further developed so that the expert system helps the model user choose the most appropriate model for a particular application from a hierarchy of models. The system currently contains seven models which range from steady state to time dependent models, for both conservative and nonconservative substances in rivers and lakes. The menu driven expert system prompts the model user for information such as the nature of the receiving water system, the type of effluent being considered, and the range of background data available for use as input to the models. The system can also be used to determine the nature of the environmental conditions at the site which are not available in the textual information database, such as the components of river flow. Applications of the water quality expert system are presented for representative mine sites in the Timmins area of Ontario. PMID:24227087

Booty, W G; Lam, D C; Bobba, A G; Wong, I; Kay, D; Kerby, J P; Bowen, G S

1992-12-01

415

The immunosuppressive compound 2-acetyl-4-tetrahydroxybutyl imidazole inhibits the allogeneic mixed lymphocyte reaction by sequestration of a recirculating subpopulation of T cells.  

PubMed Central

2-acetyl-4(5)-(1,2,3,4-tetrahydroxybutyl)imidazole (THI) is an immunosuppressive component of caramel food colouring that causes lymphopenia in mice and rats by an unknown mechanism. In this study we investigated some of the affects of THI on the murine immune system. Initially we showed that splenic T lymphocytes from mice treated with 50 mg/l THI in their drinking water were unable to launch a mixed lymphocyte reaction (MLR) against allogeneic stimulator cells, and had decreased and delayed interleukin-2 (IL-2) production. However, these T cells exhibited a normal proliferative response to concanavalin A (Con A), immobilized anti-CD3 monoclonal antibody (mAb) and anti-CD3 plus anti-CD28 mAb. Furthermore, the MLR response could be restored by the addition of IL-2 to the MLR culture. Homing studies using intravenous injection of fluorescence-labelled splenocytes showed that THI treatment decreased absolute numbers of labelled T and B lymphocytes in the blood and the spleen. Furthermore, these labelled cells reappeared in the blood and the spleen when mice were taken off THI, indicating that lymphocyte recirculation and splenic homing were modified reversibly by THI treatment. Cessation of THI treatment also resulted in a rapid reappearance of MLR responsiveness in the spleen, indicating that THI treatment does not functionally impair recirculating T cells. Collectively these data are compatible with the concept that a rapidly recirculating population of T cells, which produce IL-2 in an allogeneic MLR, are lost from the blood and spleen following THI treatment, and are sequestered in other, yet to be identified, tissues.

Bradbury, M G; Doherty, K V; Parish, C R; Lyons, A B

1996-01-01

416

Biofiltration. December 1977-December 1989 (Citations from the Selected Water Resources Abstracts data base). Report for December 1977-December 1989  

SciTech Connect

This bibliography contains citations concerning the use of microbiological populations in conjunction with filter media to remove organic, inorganic, and biological contaminants in water and waste water. Filter media used include sand, carbon, plastic, rock, and wood. Common applications of this process are in municipal and industrial waste water treatment, filtration of ground water and landfill leachate, and water recirculation systems. (Contains 69 citations fully indexed and including a title list.)

Not Available

1989-12-01

417

Alternative Electrochemical Systems for Ozonation of Water  

NASA Technical Reports Server (NTRS)

Electrochemical systems that are especially well suited for the small-scale generation of ozone and ozonated water for local use have been invented. These systems can operate with very little maintenance, and the only inputs needed during operation are electric power and water. Ozonated water produced by these systems can be used in diverse industrial applications: A few examples include sterilization in the brewing industry, general disinfection, and treatment of sewage and recycled water. The basic principle of operation admits of several alternative system configurations. The heart of the system is a stack of electrolytic cells, each containing a proton-exchange membrane (which serves as a solid electrolyte) sandwiched between a catalytic anode and a catalytic cathode. Preferably, the proton-exchange membrane is made of a perfluorinated sulfonic acid polymer. During electrolysis, a mixture of O2 and O3 gases is generated at the anode and H2 is generated at the cathode. Some of the O3 generated at the anode becomes dissolved in the water. The proportion of O3 in the O2/O3 mixture can be maximized by the selection of suitable electrode materials and the use of a high overpotential. Although the proton-exchange membrane conducts protons, it does not conduct electrons. It is also impermeable by gases; consequently, it maintains separation between the O2/O3 mixture evolved at the anode and the H2 evolved at the cathode.

Andrews, Craig C.; Murphy, Oliver J.

2003-01-01

418

Impact of nitrate-enhanced leachate recirculation on gaseous releases from a landfill bioreactor cell  

SciTech Connect

This study evaluates the impact of nitrate injection on a full scale landfill bioreactor through the monitoring of gaseous releases and particularly N{sub 2}O emissions. During several weeks, we monitored gas concentrations in the landfill gas collection system as well as surface gas releases with a series of seven static chambers. These devices were directly connected to a gas chromatograph coupled to a flame ionisation detector and an electron capture detector (GC-FID/ECD) placed directly on the field. Measurements were performed before, during and after recirculation of raw leachate and nitrate-enhanced leachate. Raw leachate recirculation did not have a significant effect on the biogas concentrations (CO{sub 2}, CH{sub 4} and N{sub 2}O) in the gas extraction network. However, nitrate-enhanced leachate recirculation induced a marked increase of the N{sub 2}O concentrations in the gas collected from the recirculation trench (100-fold increase from 0.2 ppm to 23 ppm). In the common gas collection system however, this N{sub 2}O increase was no more detectable because of dilution by gas coming from other cells or ambient air intrusion. Surface releases through the temporary cover were characterized by a large spatial and temporal variability. One automated chamber gave limited standard errors over each experimental period for N{sub 2}O releases: 8.1 {+-} 0.16 mg m{sup -2} d{sup -1} (n = 384), 4.2 {+-} 0.14 mg m{sup -2} d{sup -1} (n = 132) and 1.9 {+-} 0.10 mg m{sup -2} d{sup -1} (n = 49), during, after raw leachate and nitrate-enhanced leachate recirculation, respectively. No clear correlation between N{sub 2}O gaseous surface releases and recirculation events were evidenced. Estimated N{sub 2}O fluxes remained in the lower range of what is reported in the literature for landfill covers, even after nitrate injection.

Tallec, G.; Bureau, C. [Cemagref, UR HBAN, Parc de Tourvoie, BP44, F-92163 Antony (France); Peu, P.; Benoist, J.C. [Cemagref, UR GERE, 17 Avenue de Cucille, CS 64427, F-35044 Rennes (France); Lemunier, M. [Suez-Environnement, CIRADE, 38 Av. Jean Jaures, 78440 Gargenville (France); Budka, A.; Presse, D. [SITA France, 132 Rue des 3 Fontanot, 92000 Nanterre Cedex (France); Bouchez, T. [Cemagref, UR HBAN, Parc de Tourvoie, BP44, F-92163 Antony (France)], E-mail: theodore.bouchez@cemagref.fr

2009-07-15

419

High temperature hot water distribution system study  

SciTech Connect

The existing High Temperature Hot Water (HTHW) Distribution System has been plagued with design and construction deficiencies since startup of the HTHW system, in October 1988. In October 1989, after one year of service, these deficiencies were outlined in a technical evaluation. The deficiencies included flooded manholes, sump pumps not hooked up, leaking valves, contaminated HTHW water, and no cathodic protection system. This feasibility study of the High Temperature Hot Water (HTHW) Distribution System was performed under Contract No. DACA0l-94-D-0033, Delivery Order 0013, Modification 1, issued to EMC Engineers, Inc. (EMC), by the Norfolk District Corps of Engineers, on 25 April 1996. The purpose of this study was to determine the existing conditions of the High Temperature Hot Water Distribution System, manholes, and areas of containment system degradation. The study focused on two areas of concern, as follows: * Determine existing conditions and areas of containment system degradation (leaks) in the underground carrier pipes and protective conduit. * Document the condition of underground steel and concrete manholes. To document the leaks, a site survey was performed, using state-of-the-art infrared leak detection equipment and tracer gas leak detection equipment. To document the condition of the manholes, color photographs were taken of the insides of 125 manholes, and notes were made on the condition of these manholes.

NONE

1996-12-01

420

Regenerable Iodine Water-Disinfection System  

NASA Technical Reports Server (NTRS)

Iodinated resin bed for disinfecting water regenerated to extend useful life. Water flows through regeneration bed of crystalline iodine during regeneration. At other times, flow diverted around regeneration bed. Although regeneration cycle manually controlled readily automated to start and stop according to signals from concentration sensors. Further benefit of regeneration is bed provides highly concentrated biocide source when needed. Concentrated biocide used to superiodinate system after contamination from routine maintenance or unexpected introduction of large concentration of microbes.

Sauer, Richard L.; Colombo, Gerald V.; Jolly, Clifford D.

1994-01-01

421

Water in primitive solar system bodies  

Microsoft Academic Search

This is a dissertation on the physical properties, particularly, the water distribution in three small body populations of the solar system: (1) the Jovian Trojans, (2) the main-belt B-type asteroids and (3) the comets. Using near-infrared (NIR) spectroscopy, I have sought diagnostic (especially water) features in the Trojans. My sample is focused on objects identified in previous measurements as being

Bin Yang

2009-01-01

422

Water injected fuel cell system compressor  

DOEpatents

A fuel cell system including a dry compressor for pressurizing air supplied to the cathode side of the fuel cell. An injector sprays a controlled amount of water on to the compressor's rotor(s) to improve the energy efficiency of the compressor. The amount of water sprayed out the rotor(s) is controlled relative to the mass flow rate of air inputted to the compressor.

Siepierski, James S. (Williamsville, NY); Moore, Barbara S. (Victor, NY); Hoch, Martin Monroe (Webster, NY)

2001-01-01

423

A changing framework for urban water systems.  

PubMed

Urban water infrastructure and the institutions responsible for its management have gradually evolved over the past two centuries. Today, they are under increasing stress as water scarcity and a growing recognition of the importance of factors other than the cost of service provision are forcing a reexamination of long-held ideas. Research and development that supports new technological approaches and more effective management strategies are needed to ensure that the emerging framework for urban water systems will meet future societal needs. PMID:23650975

Hering, Janet G; Waite, T David; Luthy, Richard G; Drewes, Jörg E; Sedlak, David L

2013-10-01

424

Commerical solar water heating systems operational test  

Microsoft Academic Search

The performance of six commercially available solar water heaters is evaluated. The six systems are installed side-by-side on a typical roof structure and provide two examples each of silicone oil, antifreeze, and drain-back freeze protection. Each system is instrumented with Btu and KWH meters to assess performance under an imposed load profile. The systems, the instrumentation, operational results acquired over

G. R. Guinn; B. J. Novell; L. L. Hummer

1981-01-01

425

Commercial solar water heating systems operational test  

Microsoft Academic Search

The features, systems, and instrumentation of the Alabama Solar Energy Center, which is monitoring the long term performance of six commercially available flat plate collector systems, are described. The flat plates are installed in parallel on the same sloping south-facing roof, and all are fed a constant 3.79 l\\/min flow water. The systems are outfitted with either silicone, oil, drain-back

G. R. Guinn; B. J. Novell; L. Hummer

1981-01-01

426

AOIPS water resources data management system  

NASA Technical Reports Server (NTRS)

A geocoded data management system applicable for hydrological applications was designed to demonstrate the utility of the Atmospheric and Oceanographic Information Processing System (AOIPS) for hydrological applications. Within that context, the geocoded hydrology data management system was designed to take advantage of the interactive capability of the AOIPS hardware. Portions of the Water Resource Data Management System which best demonstrate the interactive nature of the hydrology data management system were implemented on the AOIPS. A hydrological case study was prepared using all data supplied for the Bear River watershed located in northwest Utah, southeast Idaho, and western Wyoming.

Merritt, E. S.; Shotwell, R. L.; Place, M. C.; Belknap, N. J.

1976-01-01

427

Removal of acidic pharmaceuticals within a nitrifying recirculating biofilter.  

PubMed

The fate of pharmaceutically active compounds (PhACs) in wastewater treatment systems is an area of increasing concern. Little research has been done to understand this issue in rural or decentralized communities. The objective of this research was to examine the ability of a bench scale nitrifying recirculating biofilter (RBF) to remove four acidic PhACs: gemfibrozil, naproxen, ibuprofen and diclofenac from secondary treated municipal wastewater at concentrations of 20 and 200?g/L. The average removals in this study were between 92 and 99% for ibuprofen, 89 and 99% for naproxen, 62 and 92% for gemfibrozil and 40 and 76% for diclofenac, which is consistent with literature. Ibuprofen and naproxen were largely removed through biological transformation; whereas gemfibrozil and diclofenac showed more variable removal, likely due to both biological transformation and sorption processes. PhAC removal in the RBFs was repeatable between trials, robust and responsive to system upsets, and the presence of PhACs as a single compound versus mixtures had no impact on PhAC removal efficiency. In summary, this study indicates that RBFs as a nitrifying stage of a multi-stage filtration process could be a viable technology for removal of some acidic pharmaceuticals in small onsite wastewater treatment facilities. PMID:24727009

Krkošek, W H; Payne, S J; Gagnon, G A

2014-05-30

428

Water system microbial check valve development  

NASA Technical Reports Server (NTRS)

Development work on a device for the Space Shuttle that will prevent the transfer of viable microorganisms within water systems is described. The device serves as a check valve in that it prevents the transfer or cross-contamination of microorganisms from a nonpotable system into a potable water system when these systems are interconnected. In this regard, the function of the device is similar to that of the air gap found in conventional one gravity systems. The device is essentially a bed of resin material impregnated with iodine. Basic design data for a variety of flow and temperature conditions are presented, together with results of challenging the beds with suspensions of seven microorganisms including aerobes, anaerobes, and spore formers.

Colombo, G. V.; Greenley, D. R.; Putnam, D. F.

1978-01-01

429

Biodeterioration of materials in water reclamation systems  

NASA Technical Reports Server (NTRS)

The chemicals produced by the microbial processes involved in the 'biofilms' which form on the surfaces of manned spacecraft water reclamation systems encompass both metals and organic poisons; both are potential hazards to astronaut health and the growth of the plants envisioned for closed-cycle life support systems. Image analysis is here shown to be a very useful technique for the study of biofilm formation on candidate water-processor materials for Space Station Freedom. The biodeterioration of materials exposed to biofilms can be swiftly evaluated by means of electrochemical impedance spectroscopy.

Ford, Tim; Maki, James S.; Mitchell, Ralph

1992-01-01

430

LUX - A recirculating linac-based ultrafast X-ray source  

SciTech Connect

We describe the design of a proposed source of ultra-fast synchrotron radiation x-ray pulses based on a recirculating superconducting linac, with an integrated array of ultrafast laser systems. The source produces x-ray pulses with duration of 10-50 fs at a 10 kHz repetition rate, with tunability from EUV to hard x-ray regimes, and optimized for the study of ultra-fast dynamics. A high-brightness rf photocathode provides electron bunches. An injector linac accelerates the beam to the 100 MeV range, and is followed by four passes through a 700 MeV recirculating linac. Ultrafast hard x-ray pulses are obtained by a combination of electron bunch manipulation, transverse temporal correlation of the electrons, and x-ray pulse compression. EUV and soft x-ray pulses as short as 10 fs are generated in a harmonic-cascade free electron laser scheme.

Corlett, J.N.; Barletta, W.A.; DeSantis, S.; Doolittle, L.; Fawley, W.M.; Green, M.A.; Heimann, P.; Leone, S.R.; Lidia, S.; Li, D.; Parmigiani, F.; Ratti, A.; Robinson, K.; Schoenlein, R.; Staples, J.; Wan, W.; Wells, R.; Wilcox, R.; Wolski, A.; Zholents, A.

2003-08-01

431

GIS-BASED WATER BALANCE SYSTEM FOR INTEGRATED SUSTAINABILITY MANAGEMENT OF WATER DISTRIBUTION ASSETS  

Microsoft Academic Search

Water loss from water distribution systems is a major concern to water utilities. Water utilities around the world are becoming more focused on adopting a proactive approach to managing water loss. The amount of lost water can be significant, reaching levels as high as 50% of production. However, water loss management is still not widely practiced by utilities in North

Delta Regina Hotel; Saskatchewan Regina; Mahmoud R. Halfawy; Osama Hunaidi

432

Colorado Springs Utilities Case Study: Water System Calibration\\/Optimization  

Microsoft Academic Search

Colorado Springs Utilities (Utility) provides water service to a rapidly growing population of 400,000. The Utility also owns and operates the Green Mountain Falls (GMF) water system located several miles outside of city limits. The GMF water system, serving 937 customers, is a separate water system consisting of small diameter cast iron and ductile iron water pipes. A significant portion

Istvan Lippai

433

Absorption cold and warm water system utilizing solar heat  

SciTech Connect

An absorbtion cold and warm water system utilizing solar heat is disclosed. Heat source water is obtained by heating water by the solar heat and a main heating source. The system is selectively made to function as a warm water system, a first heat pump and a second heat pump in accordance with temperature conditions associated with the heat source water.

Hibino, Y.; Kamejima, K.; Nara, Y.

1985-02-12

434

Wash water waste pretreatment system study  

NASA Technical Reports Server (NTRS)

The use of real wash water had no adverse effect on soap removal when an Olive Leaf soap based system was used; 96 percent of the soap was removed using ferric chloride. Numerous chemical agents were evaluated as antifoams for synthetic wash water. Wash water surfactants used included Olive Leaf Soap, Ivory Soap, Neutrogena and Neutrogena Rain Bath Gel, Alipal CO-436, Aerosol 18, Miranol JEM, Palmeto, and Aerosol MA-80. For each type of soapy wash water evaluated, at least one antifoam capable of causing nonpersistent foam was identified. In general, the silicones and the heavy metal ions (i.e., ferric, aluminum, etc.) were the most effective antifoams. Required dosage was in the range of 50 to 200 ppm.

1976-01-01

435

Standards and guides of water treatment and water-distribution systems. Manual for 1974-86  

SciTech Connect

The following five important documents are compiled for design of municipal water treatment facilities and water distribution systems: (1) Ten States Recommended Standards for Water Works; (2) A Public Water Supply Guide--Designing Community Water Systems; (3) Water Supply Guide Lines for Public Water Systems; (4) American National Standard for the Thickness Design of Ductile-Iron Pipe; and (5) Designing for Cast Iron Pipe.

Wang, L.K.; Wang, M.H.S.

1987-01-15

436

AOIPS water resources data management system  

NASA Technical Reports Server (NTRS)

The text and computer-generated displays used to demonstrate the AOIPS (Atmospheric and Oceanographic Information Processing System) water resources data management system are investigated. The system was developed to assist hydrologists in analyzing the physical processes occurring in watersheds. It was designed to alleviate some of the problems encountered while investigating the complex interrelationships of variables such as land-cover type, topography, precipitation, snow melt, surface runoff, evapotranspiration, and streamflow rates. The system has an interactive image processing capability and a color video display to display results as they are obtained.

Vanwie, P.

1977-01-01

437

40 CFR 257.22 - Ground-water monitoring systems.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 2009-07-01 false Ground-water monitoring systems. 257.22...Non-Hazardous Waste Disposal Units Ground-Water Monitoring and Corrective Action § 257.22 Ground-water monitoring systems. (a)...

2009-07-01

438

40 CFR 258.51 - Ground-water monitoring systems.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2011-07-01 true Ground-water monitoring systems. 258.51 Section...MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51 Ground-water monitoring systems. (a) A...

2012-07-01

439

40 CFR 258.51 - Ground-water monitoring systems.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Ground-water monitoring systems. 258.51 Section...MUNICIPAL SOLID WASTE LANDFILLS Ground-Water Monitoring and Corrective Action § 258.51 Ground-water monitoring systems. (a) A...

2011-07-01

440

Water Treatment Systems for Long Spaceflights  

NASA Technical Reports Server (NTRS)

Space exploration will require new life support systems to support the crew on journeys lasting from a few days to several weeks, or longer. These systems should also be designed to reduce the mass required to keep humans alive in space. Water accounts for about 80 percent of the daily mass intake required to keep a person alive. As a result, recycling water offers a high return on investment for space life support. Water recycling can also increase mission safety by providing an emergency supply of drinking water, where another supply is exhausted or contaminated. These technologies also increase safety by providing a lightweight backup to stored supplies, and they allow astronauts to meet daily drinking water requirements by recycling the water contained in their own urine. They also convert urine into concentrated brine that is biologically stable and nonthreatening, and can be safely stored onboard. This approach eliminates the need to have a dedicated vent to dump urine overboard. These needs are met by a system that provides a contaminant treatment pouch, referred to as a urine cell or contaminant cell, that converts urine or another liquid containing contaminants into a fortified drink, engineered to meet human hydration, electrolyte, and caloric requirements, using a variant of forward osmosis (FO) to draw water from a urine container into the concentrated fortified drink as part of a recycling stage. An activated carbon pretreatment removes most organic molecules. Salinity of the initial liquid mix (urine plus other) is synergistically used to enhance the precipitation of organic molecules so that activated carbon can remove most of the organics. A functional osmotic bag is then used to remove inorganic contaminants. If a contaminant is processed for which the saline content is different than optimal for precipitating organic molecules, the saline content of the liquid should be adjusted toward the optimal value for that contaminant. A first urine treatment method converts urine into a fortified sports drink, resembling Gatorade, using a first urine cell.

FLynn, Michael T.

2012-01-01

441

[Case study of red water phenomenon in drinking water distribution systems caused by water source switch].  

PubMed

Red water phenomenon occurred in some communities of a city in China after water source switch in recent days. The origin of this red water problem and mechanism of iron release were investigated in the study. Water quality of local and new water sources was tested and tap water quality in suffered area had been monitored for 3 months since red water occurred. Interior corrosion scales on the pipe which was obtained from the suffered area were analyzed by XRD, SEM, and EDS. Corrosion rates of cast iron under the conditions of two source water were obtained by Annular Reactor. The influence of different source water on iron release was studied by pipe section reactor to simulate the distribution systems. The results indicated that large increase of sulfate concentration by water source shift was regarded as the cause of red water problem. The Larson ratio increased from about 0.4 to 1.7-1.9 and the red water problem happened in the taps of some urban communities just several days after the new water source was applied. The mechanism of iron release was concluded that the stable shell of scales in the pipes had been corrupted by this kind of high-sulfate-concentration source water and it was hard to recover soon spontaneously. The effect of sulfate on iron release of the old cast iron was more significant than its effect on enhancing iron corrosion. The rate of iron release increased with increasing Larson ratio, and the correlation of them was nonlinear on the old cast-iron. The problem remained quite a long time even if the water source re-shifted into the blended one with only small ratio of the new source and the Larson ratio reduced to about 0.6. PMID:20187386

Wang, Yang; Zhang, Xiao-jian; Chen, Chao; Pan, An-jun; Xu, Yang; Liao, Ping-an; Zhang, Su-xia; Gu, Jun-nong

2009-12-01

442

Water electrolysis system refurbishment and testing  

NASA Technical Reports Server (NTRS)

The electrolytic oxygen generator for the back-up water electrolysis system in a 90-day manned test was refurbished, improved and subjected to a 182-day bench test. The performance of the system during the test demonstrated the soundness of the basic electrolysis concept, the high development status of the automatic controls which allowed completely hands-off operation, and the capability for orbital operation. Some design improvements are indicated.

Greenough, B. M.

1972-01-01

443

CLASSIFICATION OF THE MGR SITE WATER SYSTEM  

SciTech Connect

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) site water system structures, systems and components (SSCs) performed by the MGR Safety Assurance Department. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 1998). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (QARD) (DOE 1998).

J.A. Ziegler

1999-08-31

444

Southern Black Hills Water System Appraisal Report.  

National Technical Information Service (NTIS)

On June 30, 2010, The Souther Balck Hills Water System, Inc. (SBH) requested Reclamation review of their Preliminary Engineering Report (Volumes 1 and 2) (PER) (SBH 2005V1 and SBH 2005V2) to determine if it met the requirements of a Feasibility Study unde...

2011-01-01

445

CONSTANT VOLUME SAMPLING SYSTEM WATER CONDENSATION  

EPA Science Inventory

Combustion of organic motor vehicle fuels produces carbon dioxide and water (H2O) vapor (and also products of incomplete combustion, e.g. hydrocarbons and carbon monoxide, at lower concentrations). he Constant Volume Sampling (CVS) system, commonly used to condition auto exhaust ...

446

Cropping Systems and Water Quality Concerns  

Microsoft Academic Search

The impact of cropping systems on water quality is uncertain, and its interpretation depends heavily upon our definition of acceptable risk. As a means of determining net effect, both classical and precautionary approaches to assessing risk have their strengths and weaknesses. Relating the impact of cropping practices to human health outcomes can be particularly difficult. A variety of guidelines and

D. Brook Harker; Brian McConkey; Helen H. McDuffie

2003-01-01

447

Portable Deaerator for Deionized Water Systems.  

National Technical Information Service (NTIS)

The flowing water deaerator systems were designed and built for the TEMPO microwave pulser. The TEMPO program major goals were to build three one-megavolt, rep-rate pulsers capable of providing high power pulsed microwaves for various susceptibility and b...

K. T. Lancaster

1987-01-01

448

SMALL WATER SYSTEMS: ROLE OF TECHNOLOGY  

EPA Science Inventory

Over 90% of the nation's water supplies serve fewer than 10,000 people, less than 25% of the total population. Many of these small systems have problems. One of the major problems is their lack of operating revenues. They cannot benefit from economies of scale as do large urban s...

449

The water resources information system for Thailand  

Microsoft Academic Search

The paper gives a detailed account of the motivation for and the design and implementation of a computer?based system for managing the water resources in Thailand. The problems and difficulties encountered are discussed and lessons are drawn which can help to guide such undertakings in the future.

Anumongkol Sirivedhin; Vichit Lorchirachoonkul; Somboonwan Satayarakvit

1987-01-01

450

Conceptual Patterns for Water Resources Information Systems  

Microsoft Academic Search

Water Resources Information Systems (WRIS) present different types of problems during the data storage and analysis phases, related with the complex nature of the environmental data spacio-temporal phenomena. There are many questions to deal with, such as geographic representation of environmental variables, large time- series management, measurements and observations related with different hydrologic phenomena recording and the integration of simulations

Adriana B. Urciuolo; Rodolfo J. Iturraspe

2003-01-01

451

Regional Water Quality-Quantity Systems Analysis.  

National Technical Information Service (NTIS)

The project objective is to develop and demonstrate a pragmatic methodology for total planning of an integrated water supply-liquid waste handling system on a regional scale (county wide and larger). This will require defining the location, the size and t...

W. C. Manuel D. W. Hendricks H. J. Morel-Seytoux

1971-01-01

452

Advanced Water Vapor Lidar Detection System.  

National Technical Information Service (NTIS)

In the present water vapor lidar system, the detected signal is sent over long cables to a waveform digitizer in a CAMAC crate. This has the disadvantage of transmitting analog signals for a relatively long distance, which is subjected to pickup noise, le...

H. Elsayed-Ali

1998-01-01

453

Wheat response to differences in water and nutritional status between zeoponic and hydroponic growth systems  

NASA Technical Reports Server (NTRS)

Hydroponic culture has traditionally been used for controlled environment life support systems (CELSS) because the optimal environment for roots supports high growth rates. Recent developments in zeoponic substrate and microporous tube irrigation (ZPT) also offer high control of the root environment. This study compared the effect of differences in water and nutrient status of ZPT or hydroponic culture on growth and yield of wheat (Triticum aestivum L. cv. USU-Apogee). In a side-by-side test in a controlled environment, wheat was grown in ZPT and recirculating hydroponics to maturity. Water use by plants grown in both culture systems peaked at 15 to 20 L m-2 d-1 up to Day 40, after which it declined more rapidly for plants grown in ZPT culture due to earlier senescence of leaves. No consistent differences in water status were noted between plants grown in the two culture systems. Although yield was similar, harvest index was 28% lower for plants grown in ZPT than in hydroponic culture. Sterile green tillers made up 12 and 0% of the biomass of plants grown in ZPT and hydroponic culture, respectively. Differences in biomass partitioning were attributed primarily to NH4-N nutrition of plants grown in ZPT compared with NO3-N in hydroponic nutrient solution. It is probable that NH4-N-induced Ca deficiency produced excess tillering and lower harvest index for plants grown in ZPT culture. These results suggest that further refinements in zeoponic substrate would make ZPT culture a viable alternative for achieving high productivity in a CELSS.

Steinberg, S. L.; Ming, D. W.; Henderson, K. E.; Carrier, C.; Gruener, J. E.; Barta, D. J.; Henninger, D. L.

2000-01-01

454

A Water Recovery System Evolved for Exploration  

NASA Technical Reports Server (NTRS)

A new water recovery system designed towards fulfillment of NASA's Vision for Space Exploration is presented. This water recovery system is an evolution of the current state-of-the-art system. Through novel integration of proven technologies for air and water purification, this system promises to elevate existing technology to higher levels of optimization. The novel aspect of the system is twofold: Volatile organic contaminants will be removed from the cabin air via catalytic oxidation in the vapor phase, prior to their absorption into the aqueous phase, and vapor compression distillation technology will be used to process the condensate and hygiene waste streams in addition to the urine waste stream. Oxidation kinetics dictate that removal of volatile organic contaminants from the vapor phase is more efficient. Treatment of the various waste streams by VCD will reduce the load on the expendable ion exchange and adsorption media which follow, and on the aqueous-phase volatile removal assembly further downstream. Incorporating these advantages will reduce the weight, volume, and power requirements of the system, as well as resupply.

ORourke, Mary Jane E.; Perry, Jay L.; Carter, Donald L.

2006-01-01

455

Dispersion processes and residence times in a semi-enclosed basin with recirculating gyres: An application to the Tyrrhenian Sea  

Microsoft Academic Search

In this paper we investigate the dispersion of a tracer in a semi-enclosed basin characterized by a steady flow with recirculations. In particular, we focus on the macroscopic behavior of the system, characterized by the total concentration of the tracer in the basin, C(t), and by its residence time T. As a case study, the circulation in an idealized basin

Giuseppe Buffoni; Pierpaolo Falco; Annalisa Griffa; Enrico Zambianchi

1997-01-01

456

Exhaust Gas Recirculation for Retrofit NOx Control on Natural Gas Engines. Topical Report January-April 1988,  

National Technical Information Service (NTIS)

Data on exhaust gas recirculation obtained from Tenneco Gas Transportation Company were reviewed and analyzed, and a basic EGR system design and cost estimate were developed. EGR can provide practical NOx reductions of up to 50 percent in 2-cycle natural ...

C. M. Urban

1989-01-01

457

Developing Sustainable Spacecraft Water Management Systems  

NASA Technical Reports Server (NTRS)

It is well recognized that water handling systems used in a spacecraft are prone to failure caused by biofouling and mineral scaling, which can clog mechanical systems and degrade the performance of capillary-based technologies. Long duration spaceflight applications, such as extended stays at a Lunar Outpost or during a Mars transit mission, will increasingly benefit from hardware that is generally more robust and operationally sustainable overtime. This paper presents potential design and testing considerations for improving the reliability of water handling technologies for exploration spacecraft. Our application of interest is to devise a spacecraft wastewater management system wherein fouling can be accommodated by design attributes of the management hardware, rather than implementing some means of preventing its occurrence.

Thomas, Evan A.; Klaus, David M.

2009-01-01

458

Regenerable Iodine Water-Disinfection System  

NASA Technical Reports Server (NTRS)

Iodinated resin bed for disinfecting water regenerated to extend its useful life. Water flows through regeneration bed of crystalline iodine during regeneration. At other times, flow diverted around regeneration bed. Although regeneration cycle was manually controlled in demonstration, readily automated to start and stop according to signals and stop according to signals from concentration sensors. Further benefit of regeneration is that regeneration bed provides highly concentrated biocide source (200 mg/L) when needed. Concentrated biocide used to superiodinate system after contamination from routine maintenance or unexpected introduction of large concentration of microbes.

Sauer, Richard L.; Colombo, Gerald V.; Jolly, Clifford D.

1994-01-01

459

Bolivian villagers embrace new water system.  

PubMed

The USAID-CARE Bolivia Child Survival and Rural Sanitation Project brought water to Tauca, a community on the shores of Lake Titicaca. Water is used for washing hands and vegetables which leads to better hygiene and nutrition and is crucial in view of the current cholera epidemic in South America. Farmers often start small irrigation projects for vegetable gardens. A gravity-pumped water system was designed by a CARE engineer but built of local materials by local people in the Bolivian village of Phorejoni Junco. 2 community-trained water operators and 2 health workers visit each home and inspect the sanitation system every month. Llamacachi, a model community with 77 families, has built a clinic with minimal material and labor commitments and additional money from water fees. All 17 children under the age of 5 have received health cards. Only 10% of the children are malnourished, and half of the 79 community mothers know how to prepare oral rehydration fluid for children with diarrhea. In 1989 the CARE project, funded by USAID, set out to improve the health and self-sufficiency of 48,000 people in 160 communities in the Bolivian departments of La Paz, Cochabamba, and Santa Cruz. A major objective was to better the survival rates of children under age 5 by constructing water supply systems, reinforcing community organizations and improving hygiene. In Bolivia fewer than 31% of the rural population has water services, fewer than 13% of the people have latrines, and fewer than 30% have access to health services. The mortality rate of children under age 5 is 100/1000, and 75% of those deaths are related to diarrhea or parasitic illness. The Bolivia Child Survival Project reduced infant mortality in these communities from 210 deaths to 100 deaths per 1000 children under age 5. CARE's Bolivia Child Survival Project was recently funded for 4 more years to serve an additional 160 communities, demonstrating that a sound child survival program and a focus on health depends on quality water systems. PMID:12286430

Foley, V

1993-04-01

460

Biosensor systems for pesticide determination in water  

NASA Astrophysics Data System (ADS)

Different biosensor systems suitable for the determination of pesticides in water are described. They are based on immobilized biological components, which are sensitive to compounds commonly used as pesticides. The biological components in the work described here were microorganisms capable of degrading chlorinated aromatic compounds, cholinesterases which are inhibited by carbamates and organophosphates, and antibodies specific to triazines. They were immobilized on various carriers and were either integrated in automated flow-through systems or developed as disposable electrodes. In this contribution, characteristics features of the different formats are given, e.g., the dependence of the specificity and sensitivity of the system on the biological component.

Bilitewski, Ursula; Bier, Frank F.; Beyersdorf-Radeck, Baerbel; Rueger, Petra; Zischkale, Frank; Schmid, Rolf D.

1993-03-01

461

Acceleration schedules for a recirculating heavy-ion accelerator  

SciTech Connect

Recent advances in solid-state switches have made it feasible to design programmable, high-repetition-rate pulsers for induction accelerators. These switches could lower the cost of recirculating induction accelerators, such as the ''small recirculator'' at Lawrence Livermore National Laboratory (LLNL), by substantially reducing the number of induction modules. Numerical work is reported here to determine what effects the use of fewer pulsers at higher voltage would have on the beam quality of the LLNL small recirculator. Lattices with different numbers of pulsers are examined using the fluid/envelope code CIRCE, and several schedules for acceleration and compression are compared for each configuration. For selected schedules, the phase-space dynamics is also studied using the particle-in-cell code WARP3d.

Sharp, W.M.; Grote, D.P.

2002-05-01

462

High Power Picosecond Laser Pulse Recirculation for Compton Scattering  

NASA Astrophysics Data System (ADS)

Gamma-ray generation by Compton back-scattering laser photons off a relativistic electron beam suffers from a small Thomson cross-section. Recirculating unused laser photons can increase the average gamma-ray flux. Traditional approaches to laser recirculation rely on either resonant coupling of a low-energy pulse train to a cavity or active pulse switching using a pockels cell. Our alternative, passive approach does not require interferometeric alignment accuracy and is compatible with ultrashort, high peak power pulses. Pulse injection is achieved by a thin frequency converter inside the cavity in the path of the incident beam. The cavity consists of dichroic mirrors that transmit the incident but reflect the frequency-converted light. Initial modeling and experiments predict better than 20 times increase in the average brightness of Compton back-scattering sources with our pulse recirculation method.

Shverdin, M.; Anderson, S.; Brown, C.; Betts, S.; Gibson, D.; Hernandez, J.; Johnson, M.; Jovanovic, I.; McNabb, D.; Messerly, M.; Pruet, J.; Tremaine, A.; Hartemann, F.; Siders, C.; Barty, C. P. J.

2007-11-01

463

Deficiencies in drinking water distribution systems in developing countries  

Microsoft Academic Search

Rapidly growing populations and migration to urban areas in developing countries has resulted in a vital need for the establishment of centralized water systems to disseminate potable water to residents. Protected source water and modern, well-maintained drinking water treatment plants can provide water adequate for human consumption. However, ageing, stressed or poorly maintained distribution systems can cause the quality of

Ellen J. Lee; Kellogg J. Schwab

2005-01-01

464

Agricultural-to-hydropower water transfers: sharing water and benefits in hydropower-irrigation systems  

Microsoft Academic Search

This paper presents a methodology to assess agricultural-to-hydropower water transfers in water resources systems where irrigation crop production and hydropower generation are the main economic activities. In many countries, water for crop irrigation is often considered as a static asset: irrigation water is usually allocated by a system of limited annual rights to use a prescribed volume of water. The

A. Tilmant; Q. Goor; D. Pinte

2009-01-01

465

Army Energy and Water Reporting System Assessment  

SciTech Connect

There are many areas of desired improvement for the Army Energy and Water Reporting System. The purpose of system is to serve as a data repository for collecting information from energy managers, which is then compiled into an annual energy report. This document summarizes reported shortcomings of the system and provides several alternative approaches for improving application usability and adding functionality. The U.S. Army has been using Army Energy and Water Reporting System (AEWRS) for many years to collect and compile energy data from installations for facilitating compliance with Federal and Department of Defense energy management program reporting requirements. In this analysis, staff from Pacific Northwest National Laboratory found that substantial opportunities exist to expand AEWRS functions to better assist the Army to effectively manage energy programs. Army leadership must decide if it wants to invest in expanding AEWRS capabilities as a web-based, enterprise-wide tool for improving the Army Energy and Water Management Program or simply maintaining a bottom-up reporting tool. This report looks at both improving system functionality from an operational perspective and increasing user-friendliness, but also as a tool for potential improvements to increase program effectiveness. T